Xylem is one of the two types of transport tissue in vascular plants , the other being phloem ; both of these are part of the vascular bundle . The basic function of the xylem is to transport water upward from the roots to parts of the plants such as stems and leaves, but it also transports nutrients . The word xylem is derived from the Ancient Greek word, ξύλον ( xylon ), meaning "wood"; the best-known xylem tissue is wood , though it is found throughout a plant. The term was introduced by Carl Nägeli in 1858.
192-406: Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants . It is an organic material – a natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include
384-483: A Vietnamese source from the same time period. The name possibly means Sea Town , being derived from the Malay tasek , meaning 'sea' or 'lake'. The Chinese traveller Wang Dayuan visited a place around 1330 named Danmaxi ( Chinese : 淡馬錫 ; pinyin : Dànmǎxí ; Wade–Giles : Tan Ma Hsi ) or Tam ma siak , depending on pronunciation; this may be a transcription of Temasek , alternatively, it may be
576-426: A construction material , for making tools and weapons , furniture and paper . More recently it emerged as a feedstock for the production of purified cellulose and its derivatives, such as cellophane and cellulose acetate . As of 2020, the growing stock of forests worldwide was about 557 billion cubic meters. As an abundant, carbon-neutral renewable resource, woody materials have been of intense interest as
768-561: A hinterland , the nation rapidly developed to become one of the Four Asian Tigers . As a highly developed country , it has one of the highest GDP per capita (PPP) in the world. It is also identified as a tax haven . Singapore is the only country in Asia with a AAA sovereign credit rating from all major rating agencies . It is a major aviation , financial , and maritime shipping hub and has consistently been ranked as one of
960-524: A snap election ). The 14th and current Parliament has 103 members; 93 were directly elected from the 31 constituencies , nine are nonpartisan nominated members appointed by the president, and three are non-constituency members from opposition parties who were not elected in the last general election but appointed to the legislature to increase opposition party representation. In group representation constituencies (GRCs), political parties assemble teams of candidates to contest elections. At least one MP in
1152-536: A GRC must be of an ethnic minority background. All elections are held using first-past-the-post voting . MPs host weekly political surgeries , called " Meet-the-People Sessions ", where they help constituents resolve personal issues which can be related to housing, financial assistance, and immigration. The People's Action Party occupies a dominant position in Singaporean politics, having won large parliamentary majorities in every election since self-governance
1344-611: A Muslim state, the soldiers rebelled, killing their officers and several British civilians before the mutiny was suppressed by non-Muslim troops arriving from Johore and Burma . After World War I , the British built the large Singapore Naval Base as part of the defensive Singapore strategy . Originally announced in 1921, the construction of the base proceeded at a slow pace until the Japanese invasion of Manchuria in 1931. Costing $ 60 million and not fully completed in 1938, it
1536-486: A candidate needs to be a person at least 45 years of age who is no longer a member of a political party, to either have held public office for at least 3 years in a number of specific public service leadership roles, or to have 3 years experience as chief executive of a fully profitable private sector company with at least S$ 500 million in shareholders' equity , be a resident in Singapore for at least 10 years, not have
1728-439: A closed forest, and in the manufacture of articles where strength is an important consideration such "second-growth" hardwood material is preferred. This is particularly the case in the choice of hickory for handles and spokes . Here not only strength, but toughness and resilience are important. The results of a series of tests on hickory by the U.S. Forest Service show that: Xylem The most distinctive xylem cells are
1920-578: A combination of the Malay Tanah meaning 'land' and Chinese xi meaning 'tin', which was traded on the island. Variations of the name Siṃhapura were used for a number of cities throughout the region prior to the establishment of the Kingdom of Singapura . In Hindu–Buddhist culture , lions were associated with power and protection, which may explain the attraction of such a name. The name Singapura supplanted Temasek sometime before
2112-608: A communist takeover. On 27 May 1961, Malaya's prime minister, Tunku Abdul Rahman , made a surprise proposal for a new Federation called Malaysia , which would unite the current and former British possessions in the region: the Federation of Malaya , Singapore, Brunei , North Borneo , and Sarawak . UMNO leaders believed that the additional Malay population in the Bornean territories would balance Singapore's Chinese population. The British government, for its part, believed that
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#17327799654652304-594: A criminal record, and more. Candidates must also "satisfy" the Presidential Elections Committee (PEC) that he or she is a person of integrity, good character and reputation. From 2017, the Constitution requires that presidential elections be " reserved " for a racial community if no one from that ethnic group has been elected to the presidency in the five most recent terms. Only members of that community may qualify as candidates in
2496-459: A cut from customers. In response, amendments were made to the Women's Charter by the government in 2019 to legislate more serious punishments for traffickers, including imprisonment of up to seven years and a fine of S$ 100,000. Singapore has a highly developed market economy , based historically on extended entrepôt trade. Along with Hong Kong , South Korea , and Taiwan , Singapore is one of
2688-488: A fabric with small spaces. In small passages, such as that between the plant cell walls (or in tracheids), a column of water behaves like rubber – when molecules evaporate from one end, they pull the molecules behind them along the channels. Therefore, transpiration alone provided the driving force for water transport in early plants. However, without dedicated transport vessels, the cohesion-tension mechanism cannot transport water more than about 2 cm, severely limiting
2880-556: A film of surface moisture, enabling them to grow to much greater size. As a result of their independence from their surroundings, they lost their ability to survive desiccation – a costly trait to retain. During the Devonian, maximum xylem diameter increased with time, with the minimum diameter remaining pretty constant. By the middle Devonian, the tracheid diameter of some plant lineages ( Zosterophyllophytes ) had plateaued. Wider tracheids allow water to be transported faster, but
3072-423: A great deal of resistance on flow; vessel members have perforated end walls, and are arranged in series to operate as if they were one continuous vessel. The function of end walls, which were the default state in the Devonian, was probably to avoid embolisms . An embolism is where an air bubble is created in a tracheid. This may happen as a result of freezing, or by gases dissolving out of solution. Once an embolism
3264-526: A handful of Chinese . By 1860 the population had swelled to over 80,000, more than half being Chinese . Many of these early immigrants came to work on the pepper and gambier plantations. In 1867, the Straits Settlements were separated from British India , coming under the direct control of Britain . Later, in the 1890s, when the rubber industry became established in Malaya and Singapore,
3456-401: A heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a result the wood is very uniform in texture and is easy to work. In hard pines , on
3648-400: A hundred meters from ground level to a tree 's highest branches. Transpirational pull requires that the vessels transporting the water be very small in diameter; otherwise, cavitation would break the water column. And as water evaporates from leaves, more is drawn up through the plant to replace it. When the water pressure within the xylem reaches extreme levels due to low water input from
3840-405: A large log the sapwood, because of the time in the life of the tree when it was grown, may be inferior in hardness , strength , and toughness to equally sound heartwood from the same log. In a smaller tree, the reverse may be true. In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently
4032-461: A local medical degree can opt to defer their draft. Though not required to perform military service, the number of women in the SAF has been increasing: since 1989 they have been allowed to fill military vocations formerly reserved for men. Before induction into a specific branch of the armed forces, recruits undergo at least nine weeks of basic military training. Because of the scarcity of open land on
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#17327799654654224-400: A log is on the outside, it is more or less knotty near the middle. Consequently, the sapwood of an old tree, and particularly of a forest-grown tree, will be freer from knots than the inner heartwood. Since in most uses of wood, knots are defects that weaken the timber and interfere with its ease of working and other properties, it follows that a given piece of sapwood, because of its position in
4416-533: A maritime emporium known as Temasek and subsequently a major constituent part of several successive thalassocratic empires. Its contemporary era began in 1819, when Stamford Raffles established Singapore as an entrepôt trading post of the British Empire . In 1867, Singapore came under the direct control of Britain as part of the Straits Settlements . During World War II , Singapore
4608-652: A mezzanine floor of MacDonald House exploded, killing three people and injuring 33 others. It was the deadliest of at least 42 bomb incidents which occurred during the confrontation. Two members of the Indonesian Marine Corps , Osman bin Haji Mohamed Ali and Harun bin Said , were eventually convicted and executed for the crime. The explosion caused US$ 250,000 (equivalent to US$ 2,417,107 in 2023) in damages to MacDonald House. Even after
4800-455: A million times more conductive than the inter-cell method, giving the potential for transport over longer distances, and higher CO 2 diffusion rates. The earliest macrofossils to bear water-transport tubes are Silurian plants placed in the genus Cooksonia . The early Devonian pretracheophytes Aglaophyton and Horneophyton have structures very similar to the hydroids of modern mosses. Plants continued to innovate new ways of reducing
4992-706: A newly independent country. After being expelled from Malaysia, Singapore became independent as the Republic of Singapore on 9 August 1965, with Lee Kuan Yew and Yusof bin Ishak as the first prime minister and president respectively. In 1967, the country co-founded the Association of Southeast Asian Nations (ASEAN). Race riots broke out once more in 1969. Lee Kuan Yew's emphasis on rapid economic growth, support for business entrepreneurship, and limitations on internal democracy shaped Singapore's policies for
5184-646: A plant's leaves causes water to move through its xylem. By 1891, the Polish-German botanist Eduard Strasburger had shown that the transport of water in plants did not require the xylem cells to be alive. Singapore Singapore , officially the Republic of Singapore , is an island country and city-state in Southeast Asia . The country's territory comprises one main island , 63 satellite islands and islets , and one outlying islet . It
5376-426: A plant's vascular system based on the classical research of Dixon-Joly (1894), Eugen Askenasy (1845–1903) (1895), and Dixon (1914,1924). Water is a polar molecule . When two water molecules approach one another, the slightly negatively charged oxygen atom of one forms a hydrogen bond with a slightly positively charged hydrogen atom in the other. This attractive force, along with other intermolecular forces ,
5568-481: A pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. This, it must be remembered, applies only to ring-porous woods such as oak, ash, hickory, and others of the same group, and is, of course, subject to some exceptions and limitations. In ring-porous woods of good growth, it
5760-422: A range of mechanisms to contain the damage. Small pits link adjacent conduits to allow fluid to flow between them, but not air – although these pits, which prevent the spread of embolism, are also a major cause of them. These pitted surfaces further reduce the flow of water through the xylem by as much as 30%. The diversification of xylem strand shapes with tracheid network topologies increasingly resistant to
5952-595: A reserved presidential election. In the 2017 presidential election , this combination of stringent requirements and a reserved election that required the candidate to be of the 13% Malay ethnic group led to the PEC approving a single candidate for the presidency; Halimah Yacob , considered part of the Malay community, won in an uncontested election. She also became Singapore's first female president. Members of Parliament (MPs) are elected at least every five years (or sooner with
Wood - Misplaced Pages Continue
6144-549: A robust internal structure that held long narrow channels for transporting water from the soil to all the different parts of the above-soil plant, especially to the parts where photosynthesis occurred. During the Silurian, CO 2 was readily available, so little water needed expending to acquire it. By the end of the Carboniferous, when CO 2 levels had lowered to something approaching today's, around 17 times more water
6336-632: A source of renewable energy. In 2008, approximately 3.97 billion cubic meters of wood were harvested. Dominant uses were for furniture and building construction. Wood is scientifically studied and researched through the discipline of wood science , which was initiated since the beginning of the 20th century. A 2011 discovery in the Canadian province of New Brunswick yielded the earliest known plants to have grown wood, approximately 395 to 400 million years ago . Wood can be dated by carbon dating and in some species by dendrochronology to determine when
6528-460: A source of weakness. In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder , basswood , birch , buckeye, maple, willow , and the Populus species such as aspen, cottonwood and poplar. Some species, such as walnut and cherry , are on
6720-446: A stem or root is elongating. Later, 'metaxylem' develops in the strands of xylem. Metaxylem vessels and cells are usually larger; the cells have thickenings typically either in the form of ladderlike transverse bars (scalariform) or continuous sheets except for holes or pits (pitted). Functionally, metaxylem completes its development after elongation ceases when the cells no longer need to grow in size. There are four primary patterns to
6912-421: A strange beast on the island that he took to be a lion. Seeing this as an omen, he established the town of Singapura where he encountered the beast. The second hypothesis, drawn from Portuguese sources , postulates that this mythical story is based on the real life Parameswara of Palembang . Parameswara declared independence from Majapahit and mounted a Lion Throne. After then being driven into exile by
7104-564: A tree is first formed as sapwood. The more leaves a tree bears and the more vigorous its growth, the larger the volume of sapwood required. Hence trees making rapid growth in the open have thicker sapwood for their size than trees of the same species growing in dense forests. Sometimes trees (of species that do form heartwood) grown in the open may become of considerable size, 30 cm (12 in) or more in diameter, before any heartwood begins to form, for example, in second growth hickory , or open-grown pines . No definite relation exists between
7296-422: A type of imperfection known as a knot. The dead branch may not be attached to the trunk wood except at its base and can drop out after the tree has been sawn into boards. Knots affect the technical properties of the wood, usually reducing tension strength, but may be exploited for visual effect. In a longitudinally sawn plank, a knot will appear as a roughly circular "solid" (usually darker) piece of wood around which
7488-458: A vascular bundle will contain primary xylem only. The branching pattern exhibited by xylem follows Murray's law . Primary xylem is formed during primary growth from procambium . It includes protoxylem and metaxylem. Metaxylem develops after the protoxylem but before secondary xylem. Metaxylem has wider vessels and tracheids than protoxylem. Secondary xylem is formed during secondary growth from vascular cambium . Although secondary xylem
7680-492: A wooden object was created. People have used wood for thousands of years for many purposes, including as a fuel or as a construction material for making houses , tools , weapons , furniture , packaging , artworks , and paper . Known constructions using wood date back ten thousand years. Buildings like the longhouses in Neolithic Europe were made primarily of wood. Recent use of wood has been enhanced by
7872-415: A young vascular plant grows, one or more strands of primary xylem form in its stems and roots. The first xylem to develop is called 'protoxylem'. In appearance, protoxylem is usually distinguished by narrower vessels formed of smaller cells. Some of these cells have walls that contain thickenings in the form of rings or helices. Functionally, protoxylem can extend: the cells can grow in size and develop while
Wood - Misplaced Pages Continue
8064-437: Is a lot lighter, thus cheaper to make, as vessels need to be much more reinforced to avoid cavitation. Xylem development can be described by four terms: centrarch, exarch, endarch and mesarch . As it develops in young plants, its nature changes from protoxylem to metaxylem (i.e. from first xylem to after xylem ). The patterns in which protoxylem and metaxylem are arranged are essential in studying plant morphology. As
8256-437: Is a season check in the knot, as is often the case, it will offer little resistance to this tensile stress. Small knots may be located along the neutral plane of a beam and increase the strength by preventing longitudinal shearing . Knots in a board or plank are least injurious when they extend through it at right angles to its broadest surface. Knots which occur near the ends of a beam do not weaken it. Sound knots which occur in
8448-983: Is about one degree of latitude (137 kilometres or 85 miles) north of the equator , off the southern tip of the Malay Peninsula , bordering the Strait of Malacca to the west, the Singapore Strait to the south along with the Riau Islands in Indonesia , the South China Sea to the east, and the Straits of Johor along with the State of Johor in Malaysia to the north. Singapore's history dates back at least eight hundred years, having been
8640-855: Is also a founding member of The Forum of Small States (FOSS) , a voluntary and informal grouping at the UN. Singapore maintains membership in other regional organisations, such as Asia–Europe Meeting , the Forum for East Asia-Latin American Cooperation , the Indian Ocean Rim Association , and the East Asia Summit . It is also a member of the Non-Aligned Movement, the United Nations and
8832-835: Is also a member of the United Nations , the World Trade Organization , the East Asia Summit , the Non-Aligned Movement , and the Commonwealth of Nations . The English name of "Singapore" is an anglicisation of the native Malay name for the country, Singapura ( pronounced [siŋapura] ), which was in turn derived from the Sanskrit word for 'lion city' ( Sanskrit : सिंहपुर ; romanised: Siṃhapura ; Brahmi : 𑀲𑀺𑀁𑀳𑀧𑀼𑀭 ; literally "lion city"; siṃha means 'lion', pura means 'city' or 'fortress'). Pulau Ujong
9024-499: Is also found in members of the gymnosperm groups Gnetophyta and Ginkgophyta and to a lesser extent in members of the Cycadophyta , the two main groups in which secondary xylem can be found are: The xylem, vessels and tracheids of the roots, stems and leaves are interconnected to form a continuous system of water-conducting channels reaching all parts of the plants. The system transports water and soluble mineral nutrients from
9216-456: Is also greatly increased in strength thereby. Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in visually judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood often appear on a finished surface as darker than the denser latewood, though on cross sections of heartwood
9408-428: Is an important consideration. The weakening effect is much more serious when timber is subjected to forces perpendicular to the grain and/or tension than when under load along the grain and/or compression . The extent to which knots affect the strength of a beam depends upon their position, size, number, and condition. A knot on the upper side is compressed, while one on the lower side is subjected to tension. If there
9600-422: Is dark colored and firm, and consists mostly of thick-walled fibers which form one-half or more of the wood. In inferior oak, this latewood is much reduced both in quantity and quality. Such variation is very largely the result of rate of growth. Wide-ringed wood is often called "second-growth", because the growth of the young timber in open stands after the old trees have been removed is more rapid than in trees in
9792-558: Is difficult to control completely, especially when using mass-produced kiln-dried timber stocks. Heartwood (or duramen) is wood that as a result of a naturally occurring chemical transformation has become more resistant to decay. Heartwood formation is a genetically programmed process that occurs spontaneously. Some uncertainty exists as to whether the wood dies during heartwood formation, as it can still chemically react to decay organisms, but only once. The term heartwood derives solely from its position and not from any vital importance to
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#17327799654659984-598: Is enshrined in the constitution and continues to shape national policies in education, housing, and politics. Singapore is a parliamentary republic in the Westminster tradition of unicameral parliamentary government, and its legal system is based on common law . While the country is de jure a multi-party democracy with free elections , the government under the People's Action Party (PAP) wields widespread control and political dominance . The PAP has governed
10176-474: Is formed, it usually cannot be removed (but see later); the affected cell cannot pull water up, and is rendered useless. End walls excluded, the tracheids of prevascular plants were able to operate under the same hydraulic conductivity as those of the first vascular plant, Cooksonia . The size of tracheids is limited as they comprise a single cell; this limits their length, which in turn limits their maximum useful diameter to 80 μm. Conductivity grows with
10368-399: Is in the walls, not the cavities. Hence the greater the proportion of latewood, the greater the density and strength. In choosing a piece of pine where strength or stiffness is the important consideration, the principal thing to observe is the comparative amounts of earlywood and latewood. The width of ring is not nearly so important as the proportion and nature of the latewood in the ring. If
10560-486: Is known as secondary growth ; it is the result of cell division in the vascular cambium , a lateral meristem, and subsequent expansion of the new cells. These cells then go on to form thickened secondary cell walls, composed mainly of cellulose , hemicellulose and lignin . Where the differences between the seasons are distinct, e.g. New Zealand , growth can occur in a discrete annual or seasonal pattern, leading to growth rings ; these can usually be most clearly seen on
10752-431: Is laid down on the outside of the wood previously formed, it follows that unless a tree materially increases its production of wood from year to year, the rings must necessarily become thinner as the trunk gets wider. As a tree reaches maturity its crown becomes more open and the annual wood production is lessened, thereby reducing still more the width of the growth rings. In the case of forest-grown trees so much depends upon
10944-597: Is lost much faster than CO 2 is absorbed, so plants need to replace it, and have developed systems to transport water from the moist soil to the site of photosynthesis. Early plants sucked water between the walls of their cells, then evolved the ability to control water loss (and CO 2 acquisition) through the use of stomata. Specialized water transport tissues soon evolved in the form of hydroids, tracheids, then secondary xylem, followed by an endodermis and ultimately vessels. The high CO 2 levels of Silurian-Devonian times, when plants were first colonizing land, meant that
11136-640: Is maintaining security in Southeast Asia and surrounding territories. An underlying principle is political and economic stability in the region. It has diplomatic relations with more than 180 sovereign states. As one of the five founding members of ASEAN , Singapore is a strong supporter of the ASEAN Free Trade Area (AFTA) and the ASEAN Investment Area (AIA); it is also the host of the APEC Secretariat. Singapore
11328-468: Is more complex. The water conducting capability is mostly taken care of by vessels : in some cases (oak, chestnut, ash) these are quite large and distinct, in others ( buckeye , poplar , willow ) too small to be seen without a hand lens. In discussing such woods it is customary to divide them into two large classes, ring-porous and diffuse-porous . In ring-porous species, such as ash, black locust, catalpa , chestnut, elm , hickory, mulberry , and oak,
11520-435: Is one of the principal factors responsible for the occurrence of surface tension in liquid water. It also allows plants to draw water from the root through the xylem to the leaf. Water is constantly lost through transpiration from the leaf. When one water molecule is lost another is pulled along by the processes of cohesion and tension. Transpiration pull, utilizing capillary action and the inherent surface tension of water,
11712-704: Is regarded as a key factor behind Singapore's political stability, economic growth, and harmonious social order. In 2021, the World Justice Project 's Rule of Law Index ranked Singapore as 17th overall among the world's 193 countries for adherence to the rule of law . Singapore ranked high on the factors of order and security (#3), absence of corruption (#3), regulatory enforcement (#4), civil justice (#8), and criminal justice (#7), and ranked significantly lower on factors of open government (#34), constraints on government powers (#32), and fundamental rights (#38). Singapore's stated foreign policy priority
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#173277996546511904-497: Is the primary mechanism of water movement in plants. However, it is not the only mechanism involved. Any use of water in leaves forces water to move into them. Transpiration in leaves creates tension (differential pressure) in the cell walls of mesophyll cells. Because of this tension, water is being pulled up from the roots into the leaves, helped by cohesion (the pull between individual water molecules, due to hydrogen bonds) and adhesion (the stickiness between water molecules and
12096-464: Is the right policy and that there is "clear evidence" of serious deterrence , and that the law should be looked at upon in the wider context of "saving lives", particularly citizens. In 2004, Amnesty International claimed that some legal provisions of the Singapore system for the death penalty conflict with "the right to be presumed innocent until proven guilty". The government has disputed Amnesty's claims, stating that their "position on abolition of
12288-429: Is the rule. Some others never form heartwood. Heartwood is often visually distinct from the living sapwood and can be distinguished in a cross-section where the boundary will tend to follow the growth rings. For example, it is sometimes much darker. Other processes such as decay or insect invasion can also discolor wood, even in woody plants that do not form heartwood, which may lead to confusion. Sapwood (or alburnum)
12480-412: Is the younger, outermost wood; in the growing tree it is living wood, and its principal functions are to conduct water from the roots to the leaves and to store up and give back according to the season the reserves prepared in the leaves. By the time they become competent to conduct water, all xylem tracheids and vessels have lost their cytoplasm and the cells are therefore functionally dead. All wood in
12672-399: Is then known as the latewood or summerwood. There are major differences, depending on the kind of wood. If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring
12864-461: Is usually the latewood in which the thick-walled, strength-giving fibers are most abundant. As the breadth of ring diminishes, this latewood is reduced so that very slow growth produces comparatively light, porous wood composed of thin-walled vessels and wood parenchyma. In good oak, these large vessels of the earlywood occupy from six to ten percent of the volume of the log, while in inferior material they may make up 25% or more. The latewood of good oak
13056-428: Is well worth plants' while to avoid cavitation occurring. For this reason, pits in tracheid walls have very small diameters, to prevent air entering and allowing bubbles to nucleate. Freeze-thaw cycles are a major cause of cavitation. Damage to a tracheid's wall almost inevitably leads to air leaking in and cavitation, hence the importance of many tracheids working in parallel. Once cavitation has occurred, plants have
13248-598: The 1964 race riots . On 7 August 1965, Malaysian prime minister Tunku Abdul Rahman, seeing no alternative to avoid further bloodshed (and with the help of secret negotiations by PAP leaders, as revealed in 2015) advised the Parliament of Malaysia that it should vote to expel Singapore from Malaysia. On 9 August 1965, the Malaysian Parliament voted 126 to 0 to move a bill to amend the constitution, expelling Singapore from Malaysia, which left Singapore as
13440-564: The 2004 Indian Ocean earthquake and tsunami . Since 2009, the Republic of Singapore Navy (RSN) has deployed ships to the Gulf of Aden to aid in countering piracy efforts as part of Task Force 151 . The SAF also helped in relief efforts during Hurricane Katrina , and Typhoon Haiyan . Singapore is part of the Five Power Defence Arrangements (FPDA), a military alliance with Australia, Malaysia, New Zealand, and
13632-679: The Commonwealth . While Singapore is not a formal member of the G20 , it has been invited to participate in G20 processes in most years since 2010. Singapore is also the location of the Pacific Economic Cooperation Council (PECC) Secretariat. In general, bilateral relations with other ASEAN members are strong; however, disagreements have arisen, and relations with neighbouring Malaysia and Indonesia have sometimes been strained. Malaysia and Singapore have clashed over
13824-495: The Digital and Intelligence Service . It is seen as the guarantor of the country's independence, translating into Singapore culture, involving all citizens in the country's defence. The government spent 2.7% of the country's GDP on the military in 2024, the highest in the region. After its independence, Singapore had only two infantry regiments commanded by British officers. Considered too small to provide effective security for
14016-493: The Javanese , he usurped control over Temasek . He may have rechristened the area as Singapura , recalling the throne he had been driven from. Under Japanese occupation , Singapore was renamed Syonan-to ( Japanese : 昭 南 , Hepburn : Shōnan ) , meaning 'light of the south'. Singapore is sometimes referred to by the nickname the "Garden City", in reference to its parks and tree-lined streets. Another informal name,
14208-464: The MATADOR anti-tank weapon. The SAF is being developed to respond to a wide range of issues in both conventional and unconventional warfare. The Defence Science and Technology Agency (DSTA) is responsible for procuring resources for the military. The geographic restrictions of Singapore mean that the SAF must plan to fully repulse an attack, as they cannot fall back and re-group. The small size of
14400-747: The Republic of Singapore Air Force (RSAF) maintains a number of overseas bases in Australia , the United States , and France . The RSAF's 130 Squadron is based in RAAF Base Pearce , Western Australia , and its 126 Squadron is based in the Oakey Army Aviation Centre , Queensland . The RSAF has one squadron—the 150 Squadron—based in Cazaux Air Base in southern France. The RSAF's overseas detachments in
14592-710: The Silurian (more than 400 million years ago), and trace fossils resembling individual xylem cells may be found in earlier Ordovician rocks. The earliest true and recognizable xylem consists of tracheids with a helical-annular reinforcing layer added to the cell wall . This is the only type of xylem found in the earliest vascular plants, and this type of cell continues to be found in the protoxylem (first-formed xylem) of all living groups of vascular plants. Several groups of plants later developed pitted tracheid cells independently through convergent evolution . In living plants, pitted tracheids do not appear in development until
14784-540: The Speakers' Corner . In the Corruption Perceptions Index , which ranks countries by "perceived levels of public sector corruption", Singapore has consistently ranked as one of the least corrupt countries in the world, in spite of being illiberal. Singapore's unique combination of a strong, soft authoritarian government with an emphasis on meritocracy is known as the "Singapore model", and
14976-401: The Strait of Malacca has been a cause of concern for all three countries. Close economic ties exist with Brunei , and the two share a pegged currency value, through a Currency Interchangeability Agreement between the two countries which makes both Brunei dollar and Singapore dollar banknotes and coins legal tender in either country. The first diplomatic contact with China was made in
15168-401: The grain of the rest of the wood "flows" (parts and rejoins). Within a knot, the direction of the wood (grain direction) is up to 90 degrees different from the grain direction of the regular wood. In the tree a knot is either the base of a side branch or a dormant bud. A knot (when the base of a side branch) is conical in shape (hence the roughly circular cross-section) with the inner tip at
15360-603: The hydrophilic cell walls of plants). This mechanism of water flow works because of water potential (water flows from high to low potential), and the rules of simple diffusion . Over the past century, there has been a great deal of research regarding the mechanism of xylem sap transport; today, most plant scientists continue to agree that the cohesion-tension theory best explains this process, but multiforce theories that hypothesize several alternative mechanisms have been suggested, including longitudinal cellular and xylem osmotic pressure gradients , axial potential gradients in
15552-439: The most expensive cities to live in for expatriates and foreign workers . Singapore ranks highly in key social indicators: education , healthcare , quality of life , personal safety , infrastructure , and housing , with a home-ownership rate of 88 percent. Singaporeans enjoy one of the longest life expectancies , fastest Internet connection speeds , lowest infant mortality rates , and lowest levels of corruption in
15744-429: The resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites , and very flammable. Tree stumps of old longleaf pines are often dug, split into small pieces and sold as kindling for fires. Stumps thus dug may actually remain a century or more since being cut. Spruce impregnated with crude resin and dried
15936-597: The " Little Red Dot ", was adopted after an article in the Asian Wall Street Journal of 4 August 1998 said that Indonesian President B. J. Habibie referred to Singapore as a red dot on a map. In 1299, according to the Malay Annals , the Kingdom of Singapura was founded on the island by Sang Nila Utama . Although the historicity of the accounts as given in the Malay Annals is
16128-439: The "benevolent" yet "highly authoritarian" colonial system of governance inherited from Britain rather than forging a full democracy. A conservative ideology of " Asian values " evolved to replace British rule, based on "communal loyalty, distrust of government, and avoidance of individual or collective responsibility for wider public interests", with less regard for human rights in the nascent Western sense. The fact that "neither
16320-402: The "next generation" of transport cell design, have a more rigid structure than hydroids, allowing them to cope with higher levels of water pressure. Tracheids may have a single evolutionary origin, possibly within the hornworts, uniting all tracheophytes (but they may have evolved more than once). Water transport requires regulation, and dynamic control is provided by stomata . By adjusting
16512-422: The 15th century, after the establishment of the Kingdom of Singapura on the island by a fleeing Sumatran Raja (prince) from Palembang . However, the precise time and reason for the name change is unknown. The semi-historical Malay Annals state that Temasek was christened Singapura by Sang Nila Utama , a 13th-century Sumatran Raja from Palembang . The Annals state that Sang Nila Utama encountered
16704-584: The 1970s, with full diplomatic relations established in the 1990s. China has been Singapore's largest trading partner since 2013, after surpassing Malaysia. Singapore and the United States share a long-standing close relationship, in particular in defence, the economy, health, and education. Singapore has also increased co-operation with ASEAN members and China to strengthen regional security and fight terrorism, and participated in ASEAN's first joint maritime exercise with China in 2018. It has also given support to
16896-632: The East", and military discussions often referred to the base as simply " East of Suez ". However, the British Home Fleet was stationed in Europe, and the British could not afford to build a second fleet to protect their interests in Asia. The plan was for the Home Fleet to sail quickly to Singapore in the event of an emergency. As a consequence, after World War II broke out in 1939, the fleet
17088-527: The Japanese changed its image in the eyes of Singaporeans. British Military Administration ended on 1 April 1946, and Singapore became a separate Crown Colony . In July 1947, separate Executive and Legislative Councils were established and the election of six members of the Legislative Council was scheduled for the following year. During the 1950s, Chinese communists , with strong ties to
17280-522: The PAP drop to 61% of the vote, while the Workers' Party took 10 of the 93 seats, the highest number ever won by another party. On 15 May 2024, Lawrence Wong became Singapore's fourth Prime Minister; he is the first prime minister born after independence. Singapore is a parliamentary republic based on the Westminster system . The Constitution of Singapore is the supreme law of the country, establishing
17472-567: The People's Action Party has led to Singapore being described by academics as an illiberal democracy , or a soft-authoritarian state in which the PAP faces little to no feasible political competition to its rule of the country. The multi-party democratic process of Singapore has been described as "minimal" in comparison to the state's focus on economic development and social order. According to Gordon P. Means, professor emeritus of political science at McMaster University , Singapore reinvented
17664-724: The Singapore Government to create the Singapore Armed Forces (SAF) from scratch, and Israeli instructors were brought in to train Singaporean soldiers. Military courses were conducted according to the IDF's format, and Singapore adopted a system of conscription and reserve service based on the Israeli model . Singapore still maintains strong security ties with Israel and is one of the biggest buyers of Israeli arms and weapons systems, with one recent example being
17856-471: The Temenggong's help, Raffles managed to smuggle Tengku Long back into Singapore. Raffles offered to recognise Tengku Long as the rightful Sultan of Johor, under the title of Sultan Hussein , as well as provide him with a yearly payment of $ 5000 and another $ 3000 to the Temenggong; in return, Sultan Hussein would grant the British the right to establish a trading post on Singapore. The Treaty of Singapore
18048-613: The US-led coalition to fight terrorism, with bilateral co-operation in counter-terrorism and counter-proliferation initiatives, and joint military exercises. As Singapore has diplomatic relations with both the United States and North Korea , and was one of the few countries that have relationships with both countries, in June 2018, it hosted a historic summit between US President Donald Trump and North Korean leader Kim Jong-un ,
18240-632: The United Kingdom. According to the 2024 Global Peace Index , Singapore is the 5th most peaceful country in the world. Capital punishment is a legal and enforced penalty in Singapore. The country is one of four in the developed world to retain the death penalty, along with the United States , Japan and Taiwan . Particularly, its use against drug trafficking has been a source of contention with non-governmental organisations such as Amnesty International and Human Rights Watch . The government has responded that it has "no doubts" that it
18432-773: The United States are: Luke Air Force Base in Arizona , Marana in Arizona, Mountain Home Air Force Base in Idaho , and Andersen Air Force Base in Guam . The SAF has sent forces to assist in operations outside the country, in areas such as Iraq , and Afghanistan , in both military and civilian roles. In the region, they have helped to stabilise East Timor and have provided aid to Aceh in Indonesia following
18624-431: The addition of steel and bronze into construction. The year-to-year variation in tree-ring widths and isotopic abundances gives clues to the prevailing climate at the time a tree was cut. Wood, in the strict sense, is yielded by trees , which increase in diameter by the formation, between the existing wood and the inner bark , of new woody layers which envelop the entire stem, living branches, and roots. This process
18816-473: The amount of gas exchange, they can restrict the amount of water lost through transpiration. This is an important role where water supply is not constant, and indeed stomata appear to have evolved before tracheids, being present in the non-vascular hornworts. An endodermis probably evolved during the Silu-Devonian, but the first fossil evidence for such a structure is Carboniferous. This structure in
19008-418: The annual rings of growth and the amount of sapwood. Within the same species the cross-sectional area of the sapwood is very roughly proportional to the size of the crown of the tree. If the rings are narrow, more of them are required than where they are wide. As the tree gets larger, the sapwood must necessarily become thinner or increase materially in volume. Sapwood is relatively thicker in the upper portion of
19200-502: The arrangement of protoxylem and metaxylem in stems and roots. The other three terms are used where there is more than one strand of primary xylem. In his book De plantis libri XVI (On Plants, in 16 books) (1583), the Italian physician and botanist Andrea Cesalpino proposed that plants draw water from soil not by magnetism ( ut magnes ferrum trahit , as magnetic iron attracts) nor by suction ( vacuum ), but by absorption, as occurs in
19392-448: The border between the two classes, forming an intermediate group. In temperate softwoods, there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope, the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the season have thin walls and large cell cavities. The strength
19584-408: The case of linen, sponges, or powders. The Italian biologist Marcello Malpighi was the first person to describe and illustrate xylem vessels, which he did in his book Anatome plantarum ... (1675). Although Malpighi believed that xylem contained only air, the British physician and botanist Nehemiah Grew , who was Malpighi's contemporary, believed that sap ascended both through the bark and through
19776-457: The cell walls are composed of micro-fibrils of cellulose (40–50%) and hemicellulose (15–25%) impregnated with lignin (15–30%). In coniferous or softwood species the wood cells are mostly of one kind, tracheids , and as a result the material is much more uniform in structure than that of most hardwoods . There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example. The structure of hardwoods
19968-435: The central portion one-fourth the height of the beam from either edge are not serious defects. Knots do not necessarily influence the stiffness of structural timber; this will depend on the size and location. Stiffness and elastic strength are more dependent upon the sound wood than upon localized defects. The breaking strength is very susceptible to defects. Sound knots do not weaken wood when subject to compression parallel to
20160-445: The competition of the trees in their struggle for light and nourishment that periods of rapid and slow growth may alternate. Some trees, such as southern oaks , maintain the same width of ring for hundreds of years. On the whole, as a tree gets larger in diameter the width of the growth rings decreases. As a tree grows, lower branches often die, and their bases may become overgrown and enclosed by subsequent layers of trunk wood, forming
20352-433: The contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic color variation does not imply a significant difference in the mechanical properties of heartwood and sapwood, although there may be a marked biochemical difference between the two. Some experiments on very resinous longleaf pine specimens indicate an increase in strength, due to
20544-612: The country continuously since full internal self-government was achieved in 1959, and holds a supermajority in Parliament . One of the five founding members of ASEAN , Singapore is also the headquarters of the Asia-Pacific Economic Cooperation Secretariat, the Pacific Economic Cooperation Council Secretariat, and is the host city of many international conferences and events . Singapore
20736-615: The country's third prime minister. Lee Hsien Loong's tenure included the 2007–2008 financial crisis , the resolution of a dispute over land ownership at Tanjong Pagar railway station between Singapore and Malaysia, the introduction of the two integrated resorts (IRs), located at the Marina Bay Sands and Resorts World Sentosa , and the COVID-19 pandemic . The PAP suffered its worst ever electoral results in 2011, winning just 60% of votes, amidst debate over issues including
20928-750: The death penalty is by no means uncontested internationally" and that the report contains "grave errors of facts and misrepresentations". From 1938 to 2023, sexual relations between men were technically illegal under Section 377A of the Penal Code , first introduced during British colonial rule. During the last few decades, this law was mostly unenforced and pressure to repeal it increased as homosexuality became more accepted by Singaporean society. Meanwhile, sexual relations between women had always been legal. In 2022, Prime Minister Lee Hsien Loong announced that Singapore would repeal 377A, effectively decriminalising homosexual behaviour. Nevertheless, he added that
21120-530: The delivery of fresh water to Singapore, and access by the Singapore Armed Forces to Malaysian airspace. Border issues exist with Malaysia and Indonesia, and both have banned the sale of marine sand to Singapore over disputes about Singapore's land reclamation. Some previous disputes, such as the Pedra Branca dispute , have been resolved by the International Court of Justice . Piracy in
21312-405: The disc is sucked into the pore on that side, and blocks further flow. Other plants simply tolerate cavitation. For instance, oaks grow a ring of wide vessels at the start of each spring, none of which survive the winter frosts. Maples use root pressure each spring to force sap upwards from the roots, squeezing out any air bubbles. Growing to height also employed another trait of tracheids –
21504-415: The end of a log, but are also visible on the other surfaces. If the distinctiveness between seasons is annual (as is the case in equatorial regions, e.g. Singapore ), these growth rings are referred to as annual rings. Where there is little seasonal difference growth rings are likely to be indistinct or absent. If the bark of the tree has been removed in a particular area, the rings will likely be deformed as
21696-594: The end of the 14th century, its ruler Parameswara was attacked by either the Majapahit or the Siamese, forcing him to move to Malacca where he founded the Sultanate of Malacca . Archaeological evidence suggests that the main settlement on Fort Canning Hill was abandoned around this time, although a small trading settlement continued in Singapore for some time afterwards. In 1613, Portuguese raiders burned down
21888-403: The exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very hard and heavy, while in others the opposite is true. The quality of the site where the tree grows undoubtedly affects the character of
22080-457: The fighting for Singapore were heavy, with a total of nearly 85,000 personnel captured. About 5,000 were killed or wounded, of which Australians made up the majority. Japanese casualties during the fighting in Singapore amounted to 1,714 killed and 3,378 wounded. The occupation was to become a major turning point in the histories of several nations, including those of Japan , Britain , and Singapore. Japanese newspapers triumphantly declared
22272-800: The first-ever meeting between the sitting leaders of the two nations. It also hosted the Ma–Xi meeting in 2015, the first meeting between the political leaders of the two sides of the Taiwan Strait since the end of the Chinese Civil War in 1950. The Singaporean military, arguably the most technologically advanced in Southeast Asia, consists of the Army , the Navy , the Air Force and
22464-555: The formal surrender of Japanese forces in the region from General Seishirō Itagaki on behalf of General Hisaichi Terauchi on 12 September 1945. Meanwhile, Tomoyuki Yamashita was tried by a US military commission for war crimes, but not for crimes committed by his troops in Malaya or Singapore. He was convicted and hanged in the Philippines on 23 February 1946. Much of the infrastructure in Singapore had been destroyed during
22656-435: The fourth power of diameter, so increased diameter has huge rewards; vessel elements , consisting of a number of cells, joined at their ends, overcame this limit and allowed larger tubes to form, reaching diameters of up to 500 μm, and lengths of up to 10 m. Vessels first evolved during the dry, low CO 2 periods of the late Permian, in the horsetails, ferns and Selaginellales independently, and later appeared in
22848-505: The grain. In some decorative applications, wood with knots may be desirable to add visual interest. In applications where wood is painted , such as skirting boards, fascia boards, door frames and furniture, resins present in the timber may continue to 'bleed' through to the surface of a knot for months or even years after manufacture and show as a yellow or brownish stain. A knot primer paint or solution (knotting), correctly applied during preparation, may do much to reduce this problem but it
23040-412: The greater the water content, the greater its softening effect. The moisture in wood can be measured by several different moisture meters . Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry spruce block 5 cm in section, which will sustain a permanent load four times as great as a green (undried) block of
23232-470: The height of a plant increases and upwards transport of water by xylem is considered to limit the maximum height of trees. Three phenomena cause xylem sap to flow: The primary force that creates the capillary action movement of water upwards in plants is the adhesion between the water and the surface of the xylem conduits. Capillary action provides the force that establishes an equilibrium configuration, balancing gravity. When transpiration removes water at
23424-596: The influx of foreign workers and the high cost of living. On 23 March 2015, Lee Kuan Yew died , and a one-week period of public mourning was observed nationwide. Subsequently, the PAP regained its dominance in Parliament through the September general election , receiving 69.9% of the popular vote, although this remained lower than the 2001 tally of 75.3% and the 1968 tally of 86.7%. The 2020 election held in July saw
23616-439: The introduction of the non-constituency members of parliament in 1984 to allow up to three losing candidates from opposition parties to be appointed as MPs. Group representation constituencies (GRCs) were introduced in 1988 to create multi-seat electoral divisions, intended to ensure minority representation in parliament. Nominated members of parliament were introduced in 1990 to allow non-elected non-partisan MPs. The constitution
23808-546: The island became a global centre for rubber sorting and export. Singapore was not greatly affected by the First World War (1914–18), as the conflict did not spread to Southeast Asia . The only significant event during the war was the 1915 Singapore Mutiny by Muslim sepoys from British India, who were garrisoned in Singapore. After hearing rumours that they were to be sent to fight the Ottoman Empire ,
24000-413: The key innovations that led to the success of the angiosperms . However, the occurrence of vessel elements is not restricted to angiosperms, and they are absent in some archaic or "basal" lineages of the angiosperms: (e.g., Amborellaceae , Tetracentraceae , Trochodendraceae , and Winteraceae ), and their secondary xylem is described by Arthur Cronquist as "primitively vesselless". Cronquist considered
24192-407: The larger vessels or pores (as cross sections of vessels are called) are localized in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, produced in summer, is made up of smaller vessels and a much greater proportion of wood fibers. These fibers are the elements which give strength and toughness to wood, while the vessels are
24384-498: The legal tradition established during British rule and with substantial local differences. Criminal law is based on the Indian Penal Code originally intended for British India , and was at the time as a crown colony also adopted by the British colonial authorities in Singapore and remains the basis of the criminal code in the country with a few exceptions, amendments and repeals since it came into force. Trial by jury
24576-405: The likelihood of cavitation. Cavitation occurs when a bubble of air forms within a vessel, breaking the bonds between chains of water molecules and preventing them from pulling more water up with their cohesive tension. A tracheid, once cavitated, cannot have its embolism removed and return to service (except in a few advanced angiosperms which have developed a mechanism of doing so). Therefore, it
24768-444: The long tracheary elements that transport water. Tracheids and vessel elements are distinguished by their shape; vessel elements are shorter, and are connected together into long tubes that are called vessels . Xylem also contains two other type of cells: parenchyma and fibers . Xylem can be found: In transitional stages of plants with secondary growth , the first two categories are not mutually exclusive, although usually
24960-477: The main island, training involving activities such as live firing and amphibious warfare are often carried out on smaller islands, typically barred to civilian access. However, large-scale drills, considered too dangerous to be performed in the country, have been performed in other countries such as Brunei, Indonesia, Thailand and the United States. In general, military exercises are held with foreign forces once or twice per week. Due to airspace and land constraints,
25152-408: The maturation of the metaxylem (following the protoxylem ). In most plants, pitted tracheids function as the primary transport cells. The other type of vascular element, found in angiosperms, is the vessel element . Vessel elements are joined end to end to form vessels in which water flows unimpeded, as in a pipe. The presence of xylem vessels (also called trachea ) is considered to be one of
25344-469: The merger would prevent Singapore from becoming a haven for communism. To obtain a mandate for a merger, the PAP held a referendum on the merger . This referendum included a choice of different terms for a merger with Malaysia and had no option for avoiding merger altogether. On 16 September 1963, Singapore joined with Malaya, the North Borneo, and Sarawak to form the new Federation of Malaysia under
25536-672: The merger, the Singaporean government and the Malaysian central government disagreed on many political and economic issues. Despite an agreement to establish a common market, Singapore continued to face restrictions when trading with the rest of Malaysia. In retaliation, Singapore did not extend to Sabah and Sarawak the full extent of the loans agreed to for economic development of the two eastern states. Talks soon broke down, and abusive speeches and writing became rife on both sides. This led to communal strife in Singapore, culminating in
25728-403: The mid Cretaceous in angiosperms and gnetophytes. Vessels allow the same cross-sectional area of wood to transport around a hundred times more water than tracheids! This allowed plants to fill more of their stems with structural fibers, and also opened a new niche to vines , which could transport water without being as thick as the tree they grew on. Despite these advantages, tracheid-based wood
25920-480: The moisture content of the air) retains 8–16% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry. The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect occurs in the softening action of water on rawhide, paper, or cloth. Within certain limits,
26112-433: The need for water was relatively low. As CO 2 was withdrawn from the atmosphere by plants, more water was lost in its capture, and more elegant transport mechanisms evolved. As water transport mechanisms, and waterproof cuticles, evolved, plants could survive without being continually covered by a film of water. This transition from poikilohydry to homoiohydry opened up new potential for colonization. Plants then needed
26304-527: The new country, the development of its military forces became a priority. In addition, in October 1971, Britain pulled its military out of Singapore, leaving behind only a small British, Australian and New Zealand force as a token military presence. A great deal of initial support came from Israel , a country unrecognised by Singapore's neighbouring Muslim-majority nations of Malaysia and Indonesia. The Israel Defense Forces (IDF) commanders were tasked by
26496-761: The new port. The island was then nominally ruled by Tengku Abdul Rahman , the Sultan of Johor , who was controlled by the Dutch and the Bugis . However, the Sultanate was weakened by factional division: Abdul Rahman , the Temenggong of Johor to Tengku Abdul Rahman, as well as his officials, were loyal to the Sultan's elder brother Tengku Long , who was living in exile in Penyengat Island , Riau Islands . With
26688-407: The next half-century. Economic growth continued throughout the 1980s, with the unemployment rate falling to 3% and real GDP growth averaging at about 8% up until 1999. During the 1980s, Singapore began to shift towards high-tech industries, such as the wafer fabrication sector, in order to remain competitive as neighbouring countries began manufacturing with cheaper labour. Singapore Changi Airport
26880-542: The other hand, the latewood is very dense and is deep-colored, presenting a very decided contrast to the soft, straw-colored earlywood. It is not only the proportion of latewood, but also its quality, that counts. In specimens that show a very large proportion of latewood it may be noticeably more porous and weigh considerably less than the latewood in pieces that contain less latewood. One can judge comparative density, and therefore to some extent strength, by visual inspection. No satisfactory explanation can as yet be given for
27072-480: The overall transport rate depends also on the overall cross-sectional area of the xylem bundle itself. The increase in vascular bundle thickness further seems to correlate with the width of plant axes, and plant height; it is also closely related to the appearance of leaves and increased stomatal density, both of which would increase the demand for water. While wider tracheids with robust walls make it possible to achieve higher water transport tensions, this increases
27264-404: The plant overgrows the scar. If there are differences within a growth ring, then the part of a growth ring nearest the center of the tree, and formed early in the growing season when growth is rapid, is usually composed of wider elements. It is usually lighter in color than that near the outer portion of the ring, and is known as earlywood or springwood. The outer portion formed later in the season
27456-605: The point in stem diameter at which the plant's vascular cambium was located when the branch formed as a bud. In grading lumber and structural timber , knots are classified according to their form, size, soundness, and the firmness with which they are held in place. This firmness is affected by, among other factors, the length of time for which the branch was dead while the attaching stem continued to grow. Knots materially affect cracking and warping, ease in working, and cleavability of timber. They are defects which weaken timber and lower its value for structural purposes where strength
27648-517: The population has also affected the way the SAF has been designed, with a small active force and a large number of reserves. Singapore has conscription for all able-bodied males at age 18, except those with a criminal record or who can prove that their loss would bring hardship to their families. Males who have yet to complete pre-university education, are awarded the Public Service Commission (PSC) scholarship, or are pursuing
27840-655: The press as well as some civil and political rights. In 2023, Singapore was ranked 129th out of 180 nations by Reporters Without Borders on the global Press Freedom Index . Freedom House ranks Singapore as "partly free" in its Freedom in the World report, and the Economist Intelligence Unit ranks Singapore as a "flawed democracy", the second freest rank of four, in its " Democracy Index ". All public gatherings of five or more people require police permits, and protests may legally be held only at
28032-411: The properties of the wood. Certain rot-producing fungi impart to wood characteristic colors which thus become symptomatic of weakness. Ordinary sap-staining is due to fungal growth, but does not necessarily produce a weakening effect. Water occurs in living wood in three locations, namely: In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried (in equilibrium with
28224-442: The public nor elites had experience with democracy" helped create Singapore's political culture, as dominated by status-focused hierarchies committed to economic development. The legacy of Asian values and the limited political culture within Singapore has led to the country being described as "classic illustration of soft authoritarianism", and "profoundly illiberal". The judicial system is based on English common law , continuing
28416-453: The repeal will not affect the recognition of "traditional familial and societal norms," including how marriage is defined, leaving the legal status of same-sex marriage unchanged for the time, although the possibility of civil unions was not officially ruled out. Lee described this as a compromise between the conservative (and often religious) and progressive elements of Singaporean society to prevent further political fracturing. The law
28608-415: The resistance to flow within their cells, thereby increasing the efficiency of their water transport. Bands on the walls of tubes, in fact apparent from the early Silurian onwards, are an early improvisation to aid the easy flow of water. Banded tubes, as well as tubes with pitted ornamentation on their walls, were lignified and, when they form single celled conduits, are considered to be tracheids . These,
28800-468: The reverse is commonly true. Otherwise the color of wood is no indication of strength. Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an injury, and in all probability does not of itself affect
28992-416: The roots (if, for example, the soil is dry), then the gases come out of solution and form a bubble – an embolism forms, which will spread quickly to other adjacent cells, unless bordered pits are present (these have a plug-like structure called a torus, that seals off the opening between adjacent cells and stops the embolism from spreading). Even after an embolism has occurred, plants are able to refill
29184-472: The roots covers the water transport tissue and regulates ion exchange (and prevents unwanted pathogens etc. from entering the water transport system). The endodermis can also provide an upwards pressure, forcing water out of the roots when transpiration is not enough of a driver. Once plants had evolved this level of controlled water transport, they were truly homoiohydric, able to extract water from their environment through root-like organs rather than relying on
29376-445: The roots throughout the plant. It is also used to replace water lost during transpiration and photosynthesis. Xylem sap consists mainly of water and inorganic ions, although it can also contain a number of organic chemicals as well. The transport is passive, not powered by energy spent by the tracheary elements themselves, which are dead by maturity and no longer have living contents. Transporting sap upwards becomes more difficult as
29568-699: The same sex were not wrong at all or not wrong most of the time, up from 10% in 2013. The survey found that 27% felt the same way about same-sex marriage (an increase from 15% in 2013) and 30% did so about same-sex couples adopting a child (an increase from 24% in 2013). In 2021, six Singaporeans protested for improved trans protections in the educational system outside the Ministry of Education headquarters at Buona Vista . Pimps often traffic women from neighbouring countries such as China , Malaysia and Vietnam at their brothels as well as rented apartments and hostels for higher profit margins when they get
29760-452: The same size will. The greatest strength increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected. Wood is a heterogeneous , hygroscopic , cellular and anisotropic (or more specifically, orthotropic ) material. It consists of cells, and
29952-494: The same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaves , other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips , or fibers . Wood has been used for thousands of years for fuel , as
30144-481: The settlement, and the island faded into obscurity for the next two centuries. By then, Singapore was nominally part of the Johor Sultanate . The wider maritime region and much trade was under Dutch control for the following period after the 1641 Dutch conquest of Malacca . The British governor Stamford Raffles arrived in Singapore on 28 January 1819 and soon recognised the island as a natural choice for
30336-470: The size of the earliest plants. This process demands a steady supply of water from one end, to maintain the chains; to avoid exhausting it, plants developed a waterproof cuticle . Early cuticle may not have had pores but did not cover the entire plant surface, so that gas exchange could continue. However, dehydration at times was inevitable; early plants cope with this by having a lot of water stored between their cell walls, and when it comes to it sticking out
30528-536: The spread of embolism likely facilitated increases in plant size and the colonization of drier habitats during the Devonian radiation . Conifers, by the Jurassic, developed bordered pits had valve-like structures to isolate cavitated elements. These torus-margo structures have an impermeable disc (torus) suspended by a permeable membrane (margo) between two adjacent pores. When a tracheid on one side depressurizes,
30720-433: The structure and responsibility of governance. The President is the head of state . The governance of Singapore is separated into three branches: The president is directly elected by popular vote for a renewable six-year term. Requirements for this position, which were enacted by the PAP government, are extremely stringent, such that only a handful of people qualify for the candidacy. These qualifications include that
30912-627: The subject of academic debates, it is nevertheless known from various documents that Singapore in the 14th century, then known as Temasek , was a trading port under the influence of both the Majapahit Empire and the Siamese kingdoms, and was a part of the Indosphere . These Indianised kingdoms were characterised by surprising resilience, political integrity and administrative stability. Historical sources also indicate that around
31104-462: The support offered by their lignified walls. Defunct tracheids were retained to form a strong, woody stem, produced in most instances by a secondary xylem. However, in early plants, tracheids were too mechanically vulnerable, and retained a central position, with a layer of tough sclerenchyma on the outer rim of the stems. Even when tracheids do take a structural role, they are supported by sclerenchymatic tissue. Tracheids end with walls, which impose
31296-529: The terms of the Malaysia Agreement . Under this Agreement, Singapore had a relatively high level of autonomy compared to the other states of Malaysia. Indonesia opposed the formation of Malaysia due to its own claims over Borneo and launched Konfrontasi ("Confrontation" in Indonesian) in response to the formation of Malaysia. On 10 March 1965, a bomb planted by Indonesian saboteurs on
31488-450: The top, the flow is needed to return to the equilibrium. Transpirational pull results from the evaporation of water from the surfaces of cells in the leaves . This evaporation causes the surface of the water to recess into the pores of the cell wall . By capillary action , the water forms concave menisci inside the pores. The high surface tension of water pulls the concavity outwards, generating enough force to lift water as high as
31680-543: The tough times by putting life "on hold" until more water is supplied. To be free from the constraints of small size and constant moisture that the parenchymatic transport system inflicted, plants needed a more efficient water transport system. During the early Silurian , they developed specialized cells, which were lignified (or bore similar chemical compounds) to avoid implosion; this process coincided with cell death, allowing their innards to be emptied and water to be passed through them. These wider, dead, empty cells were
31872-606: The trade unions and Chinese schools, waged a guerrilla war against the government, leading to the Malayan Emergency . The 1954 National Service riots , Hock Lee bus riots , and Chinese middle schools riots in Singapore were all linked to these events. David Marshall , pro-independence leader of the Labour Front , won Singapore's first general election in 1955. He led a delegation to London , and Britain rejected his demand for complete self-rule. He resigned and
32064-430: The tree, may well be stronger than a piece of heartwood from the same tree. Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspond to heartwood and sapwood. In
32256-445: The tree. This is evidenced by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change comes slowly. Thin sapwood is characteristic of such species as chestnut , black locust , mulberry , osage-orange , and sassafras , while in maple , ash , hickory , hackberry , beech , and pine, thick sapwood
32448-416: The trunk of a tree than near the base, because the age and the diameter of the upper sections are less. When a tree is very young it is covered with limbs almost, if not entirely, to the ground, but as it grows older some or all of them will eventually die and are either broken off or fall off. Subsequent growth of wood may completely conceal the stubs which will remain as knots. No matter how smooth and clear
32640-491: The two. It was thought that reuniting with Malaya would benefit the economy by creating a common market, alleviating ongoing unemployment woes in Singapore. However, a sizeable left-wing faction of the PAP was strongly opposed to the merger, fearing a loss of influence, and hence formed the Barisan Sosialis , after being kicked out from the PAP. The ruling party of Malaya, United Malays National Organisation (UMNO),
32832-471: The vessels of Gnetum to be convergent with those of angiosperms. Whether the absence of vessels in basal angiosperms is a primitive condition is contested, the alternative hypothesis states that vessel elements originated in a precursor to the angiosperms and were subsequently lost. To photosynthesize, plants must absorb CO 2 from the atmosphere. However, this comes at a price: while stomata are open to allow CO 2 to enter, water can evaporate. Water
33024-408: The vessels, and gel- and gas-bubble-supported interfacial gradients. Until recently, the differential pressure (suction) of transpirational pull could only be measured indirectly, by applying external pressure with a pressure bomb to counteract it. When the technology to perform direct measurements with a pressure probe was developed, there was initially some doubt about whether the classic theory
33216-627: The victory as deciding the general situation of the war. Between 5,000 and 25,000 ethnic Chinese people were killed in the subsequent Sook Ching massacre . British forces had planned to liberate Singapore in 1945/1946; however, the war ended before these operations could be carried out. After the Japanese surrender to the Allies on 15 August 1945, Singapore fell into a brief state of violence and disorder; looting and revenge-killing were widespread. British, Australian, and Indian troops led by Lord Louis Mountbatten returned to Singapore to receive
33408-410: The war, including those needed to supply utilities. A shortage of food led to malnutrition, disease, and rampant crime and violence. A series of strikes in 1947 caused massive stoppages in public transport and other services. However, by late 1947 the economy began to recover, facilitated by a growing international demand for tin and rubber. The failure of Britain to successfully defend its colony against
33600-418: The wood formed, though it is not possible to formulate a rule governing it. In general, where strength or ease of working is essential, woods of moderate to slow growth should be chosen. In ring-porous woods, each season's growth is always well defined, because the large pores formed early in the season abut on the denser tissue of the year before. In the case of the ring-porous hardwoods, there seems to exist
33792-487: The world. It has the third highest population density of any country in the world , although there are numerous green and recreational spaces as a result of urban planning . With a multicultural population and in recognition of the cultural identities of the major ethnic groups within the nation, Singapore has four official languages : English , Malay , Mandarin , and Tamil . English is the common language , with exclusive use in numerous public services . Multi-racialism
33984-400: The xylem and restore the functionality. The cohesion-tension theory is a theory of intermolecular attraction that explains the process of water flow upwards (against the force of gravity ) through the xylem of plants. It was proposed in 1894 by John Joly and Henry Horatio Dixon . Despite numerous objections, this is the most widely accepted theory for the transport of water through
34176-406: The xylem. However, according to Grew, capillary action in the xylem would raise the sap by only a few inches; to raise the sap to the top of a tree, Grew proposed that the parenchymal cells become turgid and thereby not only squeeze the sap in the tracheids but force some sap from the parenchyma into the tracheids. In 1727, English clergyman and botanist Stephen Hales showed that transpiration by
34368-517: Was occupied by Japan in 1942 and returned to British control as a separate Crown colony following Japan's surrender in 1945. Singapore gained self-governance in 1959 and, in 1963, became part of the new federation of Malaysia , alongside Malaya , North Borneo , and Sarawak . Ideological differences led to Singapore's expulsion from the federation two years later; Singapore became an independent sovereign country in 1965. After early years of turbulence and despite lacking natural resources and
34560-494: Was abolished in 1970. Singapore is known for its strict laws and conservative stances on crime; both corporal punishment (by caning ) and capital punishment (by hanging ) are retained and commonly used as legal penalties. The right to freedom of speech and association is guaranteed by Article 14(1) of the Constitution of Singapore , although there are provisions in the subsequent subsection that regulate them. The government has restricted freedom of speech and freedom of
34752-420: Was amended in 1991 to provide for an elected president who has veto power in the use of past reserves and appointments to certain public offices. In 1990, Goh Chok Tong succeeded Lee and became Singapore's second prime minister. During Goh's tenure, the country went through the 1997 Asian financial crisis and the 2003 SARS outbreak. In 2004, Lee Hsien Loong , the eldest son of Lee Kuan Yew , became
34944-468: Was correct, because some workers were unable to demonstrate negative pressures. More recent measurements do tend to validate the classic theory, for the most part. Xylem transport is driven by a combination of transpirational pull from above and root pressure from below, which makes the interpretation of measurements more complicated. Xylem appeared early in the history of terrestrial plant life. Fossil plants with anatomically preserved xylem are known from
35136-543: Was fully occupied with defending Britain, leaving Singapore vulnerable to Japanese invasion . During the Pacific War , the Japanese invasion of Malaya culminated in the Battle of Singapore . When the British force of 60,000 troops surrendered on 15 February 1942, British prime minister Winston Churchill called the defeat "the worst disaster and largest capitulation in British history". British and Empire losses during
35328-456: Was granted in 1959. The PAP, self-described as pragmatic, have a syncretic ideology combining free-market principles , civil nationalism , and welfarism . Despite promulgating restrictions on civil liberties, Singapore under the PAP has seen consistent economic growth and political stability. The most represented and popular opposition party is the centre-left Workers' Party , which holds 8 seats in Parliament. The long-standing hegemony of
35520-412: Was lost per unit of CO 2 uptake. However, even in these "easy" early days, water was at a premium, and had to be transported to parts of the plant from the wet soil to avoid desiccation . This early water transport took advantage of the cohesion-tension mechanism inherent in water. Water has a tendency to diffuse to areas that are drier, and this process is accelerated when water can be wicked along
35712-403: Was nonetheless the largest dry dock in the world, the third-largest floating dock , and had enough fuel tanks to support the entire British navy for six months. The base was defended by heavy 15-inch (380 mm) naval guns stationed at Fort Siloso , Fort Canning and Labrador, as well as a Royal Air Force airfield at Tengah Air Base . Winston Churchill touted it as the " Gibraltar of
35904-519: Was officially repealed on 3 January 2023. Pink Dot SG , an event held in support of the LGBT community, has drawn thousands of people annually since 2009 with increasing attendance. According to a survey conducted by the Institute of Policy Studies in 2019, Singaporean society has become more liberal on LGBT rights. In the survey, more than 20% of people said that sexual relations between adults of
36096-463: Was one of the earliest references to Singapore Island, which corresponds to a Chinese account from the third century referred to a place as Pú Luó Zhōng ( Chinese : 蒲 羅 中 ), a transcription of the Malay name for 'island at the end of a peninsula '. Early references to the name Temasek (or Tumasik) are found in the Nagarakretagama , a Javanese eulogy written in 1365, and
36288-488: Was opened in 1981 and Singapore Airlines was formed. The Port of Singapore became one of the world's busiest ports and the service and tourism industries also grew immensely during this period. The PAP has remained in power since independence. Some activists and opposition politicians see the government's strict regulation of political and media activities as an infringement on political rights. In response, Singapore has seen several significant political changes, such as
36480-512: Was replaced by Lim Yew Hock in 1956, and after further negotiations Britain agreed to grant Singapore full internal self-government for all matters except defence and foreign affairs on 3 June 1959. Days before, in the 30 May 1959 election , the People's Action Party (PAP) won a landslide victory. Governor Sir William Allmond Codrington Goode served as the first Yang di-Pertuan Negara (Head of State). PAP leaders believed that Singapore's future lay with Malaya, due to strong ties between
36672-427: Was signed on 6 February 1819. In 1824, a further treaty with the Sultan led to the entire island becoming a part of the British Empire . In 1826, Singapore became part of the Straits Settlements , then under the jurisdiction of British India . Singapore became the regional capital in 1836. Prior to Raffles' arrival, there were only about a thousand people living on the island, mostly indigenous Malays along with
36864-410: Was staunchly anti-communist, and it was suspected UMNO would support the non-communist factions of PAP. UMNO, initially sceptical of the idea of a merger due to distrust of the PAP government and concern that the large ethnic Chinese population in Singapore would alter the racial balance in Malaya on which their political power base depended, became supportive of the idea of the merger due to joint fear of
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