The Today sponge is a brand of plastic contraceptive sponge saturated with a spermicide nonoxynol-9 to prevent conception . While initially popular in the 1980s in the United States, it is no longer commercially available as of 2019.
121-497: The Today sponge dates back to 1976 when it was created by Bruce Ward Vorhauer. Vorhauer struggled for seven years to get the device approved and on the market. Following U.S. Food and Drug Administration (FDA) approval, the brand was rolled out in June 1981. The product, manufactured by VLI Corp. of Irvine, California , was classified as "relatively safe" by the FDA in 1984. A 1984 study in
242-519: A gain medium , a mechanism to energize it, and something to provide optical feedback . The gain medium is a material with properties that allow it to amplify light by way of stimulated emission. Light of a specific wavelength that passes through the gain medium is amplified (power increases). Feedback enables stimulated emission to amplify predominantly the optical frequency at the peak of the gain-frequency curve. As stimulated emission grows, eventually one frequency dominates over all others, meaning that
363-471: A lens system, as is always included, for instance, in a laser pointer whose light originates from a laser diode . That is possible due to the light being of a single spatial mode. This unique property of laser light, spatial coherence , cannot be replicated using standard light sources (except by discarding most of the light) as can be appreciated by comparing the beam from a flashlight (torch) or spotlight to that of almost any laser. A laser beam profiler
484-643: A medical practitioner 's supervision like ibuprofen . In 2014, the FDA added an Ebola treatment being developed by Canadian pharmaceutical company Tekmira to the Fast Track program , but halted the phase 1 trials in July pending the receipt of more information about how the drug works. This was widely viewed as increasingly important in the face of a major outbreak of the disease in West Africa that began in late March 2014 and ended in June 2016. During
605-460: A "FDA Compliant" or "FDA Acceptable". Medical countermeasures (MCMs) are products such as biologics and pharmaceutical drugs that can protect from or treat the health effects of a chemical, biological, radiological, or nuclear (CBRN) attack. MCMs can also be used for prevention and diagnosis of symptoms associated with CBRN attacks or threats. The FDA runs a program called the "FDA Medical Countermeasures Initiative" (MCMi), with programs funded by
726-425: A REMS program called iPLEDGE . Generic drugs are chemical and therapeutic equivalents of name-brand drugs, normally whose patents have expired. Approved generic drugs should have the same dosage, safety, effectiveness, strength, stability, and quality, as well as route of administration. In general, they are less expensive than their name brand counterparts, are manufactured and marketed by rival companies and, in
847-464: A broad spectrum of light or emit different wavelengths of light simultaneously. Certain lasers are not single spatial mode and have light beams that diverge more than is required by the diffraction limit . All such devices are classified as "lasers" based on the method of producing light by stimulated emission. Lasers are employed where light of the required spatial or temporal coherence can not be produced using simpler technologies. A laser consists of
968-767: A case. The FDA has a number of field offices across the United States, in addition to international locations in China, India, Europe, the Middle East, and Latin America. As of 2021, the FDA had responsibility for overseeing $ 2.7 trillion in food, medical, and tobacco products. Some 54% of its budget derives from the federal government, and 46% is covered by industry user fees for FDA services. For example, pharmaceutical firms pay fees to expedite drug reviews. According to Forbes, pharmaceutical firms provide 75% of
1089-504: A chain reaction. The materials chosen for lasers are the ones that have metastable states , which stay excited for a relatively long time. In laser physics , such a material is called an active laser medium . Combined with an energy source that continues to "pump" energy into the material, it is possible to have enough atoms or molecules in an excited state for a chain reaction to develop. Lasers are distinguished from other light sources by their coherence . Spatial (or transverse) coherence
1210-436: A coherent beam has been formed. The process of stimulated emission is analogous to that of an audio oscillator with positive feedback which can occur, for example, when the speaker in a public-address system is placed in proximity to the microphone. The screech one hears is audio oscillation at the peak of the gain-frequency curve for the amplifier. For the gain medium to amplify light, it needs to be supplied with energy in
1331-527: A company may advertise or promote a drug only for the specific indication or medical use for which it was approved by FDA. Also, an advertisement must contain a "fair balance" between the benefits and the risks (side effects) of a drug. The regulation of drug advertising in the U.S. is divided between the Food and Drug Administration (FDA) and the Federal Trade Commission (FTC), based on whether
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#17327718742511452-426: A complaint brought against the FDA by Mylan Laboratories Inc. of Pittsburgh . When its application to manufacture generics were subjected to repeated delays by the FDA, Mylan, convinced that it was being discriminated against, soon began its own private investigation of the agency in 1987. Mylan eventually filed suit against two former FDA employees and four drug-manufacturing companies, charging that corruption within
1573-419: A device lacks the spatial and temporal coherence achievable with lasers. Such a device cannot be described as an oscillator but rather as a high-gain optical amplifier that amplifies its spontaneous emission. The same mechanism describes so-called astrophysical masers /lasers. The optical resonator is sometimes referred to as an "optical cavity", but this is a misnomer: lasers use open resonators as opposed to
1694-508: A gain medium must have a gain bandwidth sufficiently broad to amplify those frequencies. An example of a suitable material is titanium -doped, artificially grown sapphire ( Ti:sapphire ), which has a very wide gain bandwidth and can thus produce pulses of only a few femtoseconds duration. Such mode-locked lasers are a most versatile tool for researching processes occurring on extremely short time scales (known as femtosecond physics, femtosecond chemistry and ultrafast science ), for maximizing
1815-480: A given pulse energy, this requires creating pulses of the shortest possible duration utilizing techniques such as Q-switching . The optical bandwidth of a pulse cannot be narrower than the reciprocal of the pulse width. In the case of extremely short pulses, that implies lasing over a considerable bandwidth, quite contrary to the very narrow bandwidths typical of CW lasers. The lasing medium in some dye lasers and vibronic solid-state lasers produces optical gain over
1936-399: A higher energy level with energy difference ΔE, it will not stay that way forever. Eventually, a photon will be spontaneously created from the vacuum having energy ΔE. Conserving energy, the electron transitions to a lower energy level that is not occupied, with transitions to different levels having different time constants. This process is called spontaneous emission . Spontaneous emission is
2057-476: A laser beam, it is highly collimated : the wavefronts are planar, normal to the direction of propagation, with no beam divergence at that point. However, due to diffraction , that can only remain true well within the Rayleigh range . The beam of a single transverse mode (gaussian beam) laser eventually diverges at an angle that varies inversely with the beam diameter, as required by diffraction theory. Thus,
2178-471: A laser is normally a material of controlled purity, size, concentration, and shape, which amplifies the beam by the process of stimulated emission described above. This material can be of any state : gas, liquid, solid, or plasma . The gain medium absorbs pump energy, which raises some electrons into higher energy (" excited ") quantum states . Particles can interact with light by either absorbing or emitting photons. Emission can be spontaneous or stimulated. In
2299-432: A long period of time. The studies are progressively longer, gradually adding more individuals as they progress from stage I to stage III, normally over a period of years, and normally involve drug companies, the government and its laboratories, and often medical schools and hospitals and clinics. However, any exceptions to the aforementioned process are subject to strict review and scrutiny and conditions, and are only given if
2420-418: A multi-level system as a method for obtaining the population inversion, later a main method of laser pumping. Townes reports that several eminent physicists—among them Niels Bohr , John von Neumann , and Llewellyn Thomas —argued the maser violated Heisenberg's uncertainty principle and hence could not work. Others such as Isidor Rabi and Polykarp Kusch expected that it would be impractical and not worth
2541-560: A new master plan for this expansion in December 2018, and construction is expected to be completed by 2035, dependent on GSA appropriations. The Office of Regulatory Affairs is considered the agency's "eyes and ears", conducting the vast majority of the FDA's work in the field. Its employees, known as Consumer Safety Officers, or more commonly known simply as investigators, inspect production, warehousing facilities, investigate complaints, illnesses, or outbreaks, and review documentation in
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#17327718742512662-651: A number of Resident Posts, which are FDA remote offices that serve a particular geographic area. ORA also includes the Agency's network of regulatory laboratories, which analyze any physical samples taken. Though samples are usually food-related, some laboratories are equipped to analyze drugs, cosmetics, and radiation-emitting devices. The Office of Criminal Investigations was established in 1991 to investigate criminal cases. To do so, OCI employs approximately 200 Special Agents nationwide who, unlike ORA Investigators, are armed, have badges, and do not focus on technical aspects of
2783-441: A process called pumping . The energy is typically supplied as an electric current or as light at a different wavelength. Pump light may be provided by a flash lamp or by another laser. The most common type of laser uses feedback from an optical cavity —a pair of mirrors on either end of the gain medium. Light bounces back and forth between the mirrors, passing through the gain medium and being amplified each time. Typically one of
2904-468: A quantum-mechanical effect and a direct physical manifestation of the Heisenberg uncertainty principle . The emitted photon has a random direction, but its wavelength matches the absorption wavelength of the transition. This is the mechanism of fluorescence and thermal emission . A photon with the correct wavelength to be absorbed by a transition can also cause an electron to drop from the higher to
3025-498: A role in monitoring safety through influence on ingredients, but they lack legal authority. According to the ACSH, it has reviewed about 1,200 ingredients and has suggested that several hundred be restricted—but there is no standard or systemic method for reviewing chemicals for safety, or a clear definition of what 'safety' even means so that all chemicals get tested on the same basis. However, on December 29, 2022, President Biden signed
3146-523: A satisfied requirement. The FDA does not approve applied coatings used in the food processing industry . There is no review process to approve the composition of nonstick coatings; nor does the FDA inspect or test these materials. Through their governing of processes, however, the FDA does have a set of regulations that cover the formulation, manufacturing, and use of nonstick coatings. Hence, materials like Polytetrafluoroethylene (Teflon) are not and cannot be considered as FDA Approved, but rather, they are
3267-432: A seminar on this idea, and Charles H. Townes asked him for a copy of the paper. In 1953, Charles H. Townes and graduate students James P. Gordon and Herbert J. Zeiger produced the first microwave amplifier, a device operating on similar principles to the laser, but amplifying microwave radiation rather than infrared or visible radiation. Townes's maser was incapable of continuous output. Meanwhile, in
3388-431: A small volume of material at the surface of a workpiece can be evaporated if it is heated in a very short time, while supplying the energy gradually would allow for the heat to be absorbed into the bulk of the piece, never attaining a sufficiently high temperature at a particular point. Other applications rely on the peak pulse power (rather than the energy in the pulse), especially to obtain nonlinear optical effects. For
3509-440: A substantial amount of research and at least some preliminary human testing has shown that they are believed to be somewhat safe and possibly effective. (See FDA Special Protocol Assessment about Phase III trials.) The FDA's Office of Prescription Drug Promotion (OPDP) has responsibilities that revolve around the review and regulation of prescription drug advertising and promotion. This is achieved through surveillance activities and
3630-646: A very narrow frequency spectrum . Temporal coherence can also be used to produce ultrashort pulses of light with a broad spectrum but durations as short as an attosecond . Lasers are used in optical disc drives , laser printers , barcode scanners , DNA sequencing instruments , fiber-optic and free-space optical communications, semiconductor chip manufacturing ( photolithography , etching ), laser surgery and skin treatments, cutting and welding materials, military and law enforcement devices for marking targets and measuring range and speed, and in laser lighting displays for entertainment. Semiconductor lasers in
3751-561: A warning to that effect. According to the industry advocacy group, the American Council on Science and Health , though the cosmetic industry is primarily responsible for its own product safety, the FDA can intervene when necessary to protect the public. In general, though, cosmetics do not require pre-market approval or testing. The ACSH says that companies must place a warning note on their products if they have not been tested, and that experts in cosmetic ingredient review also play
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3872-430: A wide bandwidth, making a laser possible that can thus generate pulses of light as short as a few femtoseconds (10 s). In a Q-switched laser, the population inversion is allowed to build up by introducing loss inside the resonator which exceeds the gain of the medium; this can also be described as a reduction of the quality factor or 'Q' of the cavity. Then, after the pump energy stored in the laser medium has approached
3993-492: A wide range of technologies addressing many different motivations. Some lasers are pulsed simply because they cannot be run in continuous mode. In other cases, the application requires the production of pulses having as large an energy as possible. Since the pulse energy is equal to the average power divided by the repetition rate, this goal can sometimes be satisfied by lowering the rate of pulses so that more energy can be built up between pulses. In laser ablation , for example,
4114-445: Is coherent . Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as optical communication, laser cutting , and lithography . It also allows a laser beam to stay narrow over great distances ( collimation ), a feature used in applications such as laser pointers , lidar , and free-space optical communication . Lasers can also have high temporal coherence , which permits them to emit light with
4235-401: Is a center of the FDA that regulates food additives and drugs that are given to animals. CVM regulates animal drugs, animal food including pet animal, and animal medical devices. The FDA's requirements to prevent the spread of bovine spongiform encephalopathy are also administered by CVM through inspections of feed manufacturers. CVM does not regulate vaccines for animals; these are handled by
4356-651: Is a separate process, and the drug must be approved through an NDA first. A drug that is approved is said to be "safe and effective when used as directed". Very rare, limited exceptions to this multi-step process involving animal testing and controlled clinical trials can be granted out of compassionate use protocols. This was the case during the 2015 Ebola epidemic with the use, by prescription and authorization, of ZMapp and other experimental treatments, and for new drugs that can be used to treat debilitating and/or very rare conditions for which no existing remedies or drugs are satisfactory, or where there has not been an advance in
4477-404: Is a transition between energy levels that match the energy carried by the photon or phonon. For light, this means that any given transition will only absorb one particular wavelength of light. Photons with the correct wavelength can cause an electron to jump from the lower to the higher energy level. The photon is consumed in this process. When an electron is excited from one state to that at
4598-480: Is also required for three-level lasers in which the lower energy level rapidly becomes highly populated, preventing further lasing until those atoms relax to the ground state. These lasers, such as the excimer laser and the copper vapor laser, can never be operated in CW mode. In 1917, Albert Einstein established the theoretical foundations for the laser and the maser in the paper " Zur Quantentheorie der Strahlung " ("On
4719-413: Is called an optical amplifier . When an optical amplifier is placed inside a resonant optical cavity, one obtains a laser. For lasing media with extremely high gain, so-called superluminescence , light can be sufficiently amplified in a single pass through the gain medium without requiring a resonator. Although often referred to as a laser (see, for example, nitrogen laser ), the light output from such
4840-462: Is emitted by stimulated emission is identical to the photon that triggered its emission, and both photons can go on to trigger stimulated emission in other atoms, creating the possibility of a chain reaction . For this to happen, many of the atoms or molecules must be in the proper excited state so that the photons can trigger them. In most materials, atoms or molecules drop out of excited states fairly rapidly, making it difficult or impossible to produce
4961-564: Is enforcement of the Federal Food, Drug, and Cosmetic Act (FD&C). However, the agency also enforces other laws, notably Section 361 of the Public Health Service Act as well as associated regulations. Much of this regulatory-enforcement work is not directly related to food or drugs but involves other factors like regulating lasers , cellular phones , and condoms . In addition, the FDA takes control of diseases in
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5082-421: Is formed by single-frequency quantum photon states distributed according to a Poisson distribution . As a result, the arrival rate of photons in a laser beam is described by Poisson statistics. Many lasers produce a beam that can be approximated as a Gaussian beam ; such beams have the minimum divergence possible for a given beam diameter. Some lasers, particularly high-power ones, produce multimode beams, with
5203-443: Is frequently used in the field, meaning "to give off coherent light," especially about the gain medium of a laser; when a laser is operating, it is said to be " lasing ". The terms laser and maser are also used for naturally occurring coherent emissions, as in astrophysical maser and atom laser . A laser that produces light by itself is technically an optical oscillator rather than an optical amplifier as suggested by
5324-421: Is impossible. In some other lasers, it would require pumping the laser at a very high continuous power level, which would be impractical, or destroying the laser by producing excessive heat. Such lasers cannot be run in CW mode. The pulsed operation of lasers refers to any laser not classified as a continuous wave so that the optical power appears in pulses of some duration at some repetition rate. This encompasses
5445-745: Is located in the White Oak area of Silver Spring, Maryland . The agency has 223 field offices and 13 laboratories located across the 50 states, the United States Virgin Islands , and Puerto Rico . In 2008, the FDA began to post employees to foreign countries, including China, India, Costa Rica, Chile, Belgium, and the United Kingdom. FDA headquarters facilities are currently located in Montgomery County and Prince George's County , Maryland. Since 1990,
5566-405: Is not the result of random thermal processes. Instead, the release of a photon is triggered by the nearby passage of another photon. This is called stimulated emission . For this process to work, the passing photon must be similar in energy, and thus wavelength, to the one that could be released by the atom or molecule, and the atom or molecule must be in the suitable excited state. The photon that
5687-472: Is responsible for protecting and promoting public health through the control and supervision of food safety , tobacco products, caffeine products, dietary supplements , prescription and over-the-counter pharmaceutical drugs (medications), vaccines , biopharmaceuticals , blood transfusions , medical devices , electromagnetic radiation emitting devices (ERED), cosmetics, animal foods & feed and veterinary products . The FDA's primary focus
5808-449: Is the branch of the FDA responsible for ensuring the safety and efficacy of biological therapeutic agents. These include blood and blood products, vaccines, allergenics, cell and tissue-based products, and gene therapy products. New biologics are required to go through a premarket approval process called a Biologics License Application (BLA), similar to that for drugs. The original authority for government regulation of biological products
5929-741: Is the branch of the FDA responsible for the premarket approval of all medical devices , as well as overseeing the manufacturing, performance and safety of these devices. The definition of a medical device is given in the FD&;C Act, and it includes products from the simple toothbrush to complex devices such as implantable neurostimulators . CDRH also oversees the safety performance of non-medical devices that emit certain types of electromagnetic radiation . Examples of CDRH-regulated devices include cellular phones , airport baggage screening equipment , television receivers , microwave ovens , tanning booths , and laser products . CDRH regulatory powers include
6050-489: Is to heat an object; some of the thermal energy being applied to the object will cause the molecules and electrons within the object to gain energy, which is then lost through thermal radiation , that we see as light. This is the process that causes a candle flame to give off light. Thermal radiation is a random process, and thus the photons emitted have a range of different wavelengths , travel in different directions, and are released at different times. The energy within
6171-504: Is to pump the laser material with a source that is itself pulsed, either through electronic charging in the case of flash lamps, or another laser that is already pulsed. Pulsed pumping was historically used with dye lasers where the inverted population lifetime of a dye molecule was so short that a high-energy, fast pump was needed. The way to overcome this problem was to charge up large capacitors which are then switched to discharge through flashlamps, producing an intense flash. Pulsed pumping
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#17327718742516292-441: Is typically expressed through the output being a narrow beam, which is diffraction-limited . Laser beams can be focused to very tiny spots, achieving a very high irradiance , or they can have a very low divergence to concentrate their power at a great distance. Temporal (or longitudinal) coherence implies a polarized wave at a single frequency, whose phase is correlated over a relatively great distance (the coherence length ) along
6413-702: Is used for a different purpose, or undergoes any substantial change. The most rigorous requirements apply to new molecular entities : drugs that are not based on existing medications. New drugs receive extensive scrutiny before FDA approval in a process called a new drug application (NDA). Under the Presidency of Donald Trump , the agency has worked to make the drug-approval process go faster. Critics, however, argue that FDA standards are not sufficiently rigorous to prevent unsafe or ineffective drugs from getting approval. New drugs are available only by prescription by default. A change to over-the-counter (OTC) status
6534-430: Is used to measure the intensity profile, width, and divergence of laser beams. Diffuse reflection of a laser beam from a matte surface produces a speckle pattern with interesting properties. The mechanism of producing radiation in a laser relies on stimulated emission , where energy is extracted from a transition in an atom or molecule. This is a quantum phenomenon that was predicted by Albert Einstein , who derived
6655-451: Is voluntary. While this remains the primary tool of post-market safety surveillance , FDA requirements for post-marketing risk management are increasing. As a condition of approval, a sponsor may be required to conduct additional clinical trials , called Phase IV trials. In some cases, the FDA requires risk management plans called Risk Evaluation and Mitigation Strategies (REMS) for some drugs that require actions to be taken to ensure that
6776-601: The American Journal of Obstetrics and Gynecology compared it with the diaphragm and found that the Today sponge was a "safe and acceptable method of contraception with an effectiveness rate in the range of other vaginal contraceptives." The Today sponge "was manufactured until 1995, when FDA imposed new manufacturing standards." The product had several setbacks while marketed, including a link to toxic shock syndrome . Personal financial problems forced Vorhauer to sell
6897-685: The Center for Drug Evaluation and Research (CDER), the Center for Devices and Radiological Health (CDRH), the Center for Biologics Evaluation and Research (CBER) and offices for the Center for Veterinary Medicine (CVM). With the passing of the FDA Reauthorization Act of 2017, the FDA projects a 64% increase in employees to 18,000 over the next 15 years and wants to add approximately 1,600,000 square feet (150,000 square metres) of office and special use space to their existing facilities. The National Capital Planning Commission approved
7018-503: The United States Department of Agriculture . The FDA regulates tobacco products with authority established by the 2009 Family Smoking Prevention and Tobacco Control Act . This Act requires color warnings on cigarette packages and printed advertising, and text warnings from the U.S. Surgeon General . Lasers A laser is a device that emits light through a process of optical amplification based on
7139-643: The coronavirus pandemic , FDA granted emergency use authorization for personal protective equipment (PPE), in vitro diagnostic equipment, ventilators and other medical devices. On March 18, 2020, FDA inspectors postponed most foreign facility inspections and all domestic routine surveillance facility inspections. In contrast, the USDA's Food Safety and Inspection Service (FSIS) continued inspections of meatpacking plants, which resulted in 145 FSIS field employees who tested positive for COVID-19, and three who died. The Center for Biologics Evaluation and Research
7260-410: The phase of the emitted light is 90 degrees in lead of the stimulating light. This, combined with the filtering effect of the optical resonator gives laser light its characteristic coherence, and may give it uniform polarization and monochromaticity, depending on the resonator's design. The fundamental laser linewidth of light emitted from the lasing resonator can be orders of magnitude narrower than
7381-437: The stimulated emission of electromagnetic radiation . The word laser is an anacronym that originated as an acronym for light amplification by stimulated emission of radiation . The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories , based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow . A laser differs from other sources of light in that it emits light that
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#17327718742517502-421: The transverse modes often approximated using Hermite – Gaussian or Laguerre -Gaussian functions. Some high-power lasers use a flat-topped profile known as a " tophat beam ". Unstable laser resonators (not used in most lasers) produce fractal-shaped beams. Specialized optical systems can produce more complex beam geometries, such as Bessel beams and optical vortexes . Near the "waist" (or focal region ) of
7623-505: The "pencil beam" directly generated by a common helium–neon laser would spread out to a size of perhaps 500 kilometers when shone on the Moon (from the distance of the Earth). On the other hand, the light from a semiconductor laser typically exits the tiny crystal with a large divergence: up to 50°. However even such a divergent beam can be transformed into a similarly collimated beam employing
7744-606: The '2023 Consolidated Budget Act', which includes the 'Cosmetics Regulatory Modernization Act of 2022 (MoCRA)', which is a stricter regulation that is different from the previous regulations. MoCRA requires compliance with matters such as serious adverse event reporting, safety substantiation, additional labeling, record keeping, and Good Manufacturing Practices (GMP). MoCRA also calls on the FDA to grant Mandatory Recall Authority and establish regulations for GMP rules, flavor allergen labeling rules, and testing methods for cosmetics containing talc. The Center for Veterinary Medicine (CVM)
7865-406: The 1990s, accounted for about a third of all prescriptions written in the United States. For a pharmaceutical company to gain approval to produce a generic drug, the FDA requires scientific evidence that the generic drug is interchangeable with or therapeutically equivalent to the originally approved drug. This is called an Abbreviated New Drug Application (ANDA). 80% of prescription drugs sold in
7986-511: The FD&C Act. OCI Special Agents often come from other criminal investigations backgrounds, and frequently work closely with the Federal Bureau of Investigation , Assistant Attorney General , and even Interpol . OCI receives cases from a variety of sources—including ORA, local agencies, and the FBI, and works with ORA Investigators to help develop the technical and science-based aspects of
8107-633: The FDA exercises differ from one category to the next. Furthermore, legislation had granted the FDA a variety of means to address violations of standards for a given substance category. Under the Dietary Supplement Health and Education Act of 1994 (DSHEA), the FDA is responsible for ensuring that manufacturers and distributors of dietary supplements and dietary ingredients meet the current requirements. These manufacturers and distributors are not allowed to advertise their products in an adulterated way, and they are responsible for evaluating
8228-724: The FDA has had employees and facilities on 130 acres (53 hectares) of the White Oak Federal Research Center in the White Oak area of Silver Spring, Maryland . In 2001, the General Services Administration (GSA) began new construction on the campus to consolidate the FDA's 25 existing operations in the Washington metropolitan area , its headquarters in Rockville , and several fragmented office buildings. The first building,
8349-713: The FDA released a statement regarding new guidelines to help food and drug manufacturers "implement protections against potential attacks on the U.S. food supply". One of the guidelines includes the Intentional Adulteration (IA) rule, which requires strategies and procedures by the food industry to reduce the risk of compromise in facilities and processes that are significantly vulnerable. The FDA also uses tactics of regulatory shaming, mainly through online publication of non-compliance, warning letters, and "shaming lists." Regulation by shaming harnesses firms' sensitivity to reputational damage. For example, in 2018,
8470-594: The FDA's drug review budget Emergency Use Authorization (EUA) is a mechanism that was created to facilitate the availability and use of medical countermeasures, including vaccines and personal protective equipment, during public health emergencies such as the Zika virus epidemic, the Ebola virus epidemic and the COVID-19 pandemic. The programs for safety regulation vary widely by the type of product, its potential risks, and
8591-881: The Food and Drug Administration is governed by various statutes enacted by the United States Congress and interpreted by the FDA. Pursuant to the Federal Food, Drug, and Cosmetic Act and accompanying legislation, the FDA has authority to oversee the quality of substances sold as food in the United States, and to monitor claims made in the labeling of both the composition and the health benefits of foods. The FDA subdivides substances that it regulates as food into various categories—including foods, food additives , added substances (human-made substances that are not intentionally introduced into food, but nevertheless end up in it), and dietary supplements . Dietary supplements or dietary ingredients include vitamins, minerals, herbs, amino acids , and enzymes . Specific standards
8712-647: The Life Sciences Laboratory, was dedicated and opened with 104 employees in December 2003. As of December 2018, the FDA campus has a population of 10,987 employees housed in approximately 3,800,000 square feet (350,000 square metres) of space, divided into ten offices and four laboratory buildings. The campus houses the Office of the Commissioner (OC), the Office of Regulatory Affairs (ORA),
8833-677: The Quantum Theory of Radiation") via a re-derivation of Max Planck 's law of radiation, conceptually based upon probability coefficients ( Einstein coefficients ) for the absorption, spontaneous emission, and stimulated emission of electromagnetic radiation. In 1928, Rudolf W. Ladenburg confirmed the existence of the phenomena of stimulated emission and negative absorption. In 1939, Valentin A. Fabrikant predicted using stimulated emission to amplify "short" waves. In 1947, Willis E. Lamb and R. C. Retherford found apparent stimulated emission in hydrogen spectra and effected
8954-509: The Soviet Union, Nikolay Basov and Aleksandr Prokhorov were independently working on the quantum oscillator and solved the problem of continuous-output systems by using more than two energy levels. These gain media could release stimulated emissions between an excited state and a lower excited state, not the ground state, facilitating the maintenance of a population inversion . In 1955, Prokhorov and Basov suggested optical pumping of
9075-574: The Today sponge was finally re-introduced in Canada in March 2003, and in the U.S. in September 2005. In January 2007, Allendale Pharmaceuticals was acquired by Synova Healthcare, Inc. In December 2007 Synova filed for bankruptcy reorganization; in 2008 the manufacturing rights to the Today sponge were purchased by Alvogen . In mid May 2009, Mayer Laboratories, Inc., the distributor of the Today sponge for
9196-602: The US, Canada and the EU, announced the Today sponge had been re-launched in the United States. At the end of 2019, Mayer Labs had issues with the equipment to manufacturer the Today sponge. As of the onset of the COVID pandemic, it is out of production with no information as to "when or if this situation will change." A 1995 Seinfeld episode, " The Sponge ", revolved around Elaine's attempts to procure her favorite form of birth control,
9317-488: The United States are generic brands. In 1989, a major scandal erupted involving the procedures used by the FDA to approve generic drugs for sale to the public. Charges of corruption in generic drug approval first emerged in 1988 during the course of an extensive congressional investigation into the FDA. The oversight subcommittee of the United States House Energy and Commerce Committee resulted from
9438-614: The acronym. It has been humorously noted that the acronym LOSER, for "light oscillation by stimulated emission of radiation", would have been more correct. With the widespread use of the original acronym as a common noun, optical amplifiers have come to be referred to as laser amplifiers . Modern physics describes light and other forms of electromagnetic radiation as the group behavior of fundamental particles known as photons . Photons are released and absorbed through electromagnetic interactions with other fundamental particles that carry electric charge . A common way to release photons
9559-842: The agency published an online "black list", in which it named dozens of branded drug companies that are supposedly using unlawful or unethical means to attempt to impede competition from generic drug companies. The FDA frequently works with other federal agencies, including the Department of Agriculture , the Drug Enforcement Administration , Customs and Border Protection , and the Consumer Product Safety Commission . They also often work with local and state government agencies in performing regulatory inspections and enforcement actions. The regulation of food and dietary supplements by
9680-468: The authority to require certain technical reports from the manufacturers or importers of regulated products, to require that radiation-emitting products meet mandatory safety performance standards, to declare regulated products defective, and to order the recall of defective or noncompliant products. CDRH also conducts limited amounts of direct product testing. Clearance requests are required for medical devices that prove they are "substantially equivalent" to
9801-476: The beam. A beam produced by a thermal or other incoherent light source has an instantaneous amplitude and phase that vary randomly with respect to time and position, thus having a short coherence length. Lasers are characterized according to their wavelength in a vacuum . Most "single wavelength" lasers produce radiation in several modes with slightly different wavelengths. Although temporal coherence implies some degree of monochromaticity , some lasers emit
9922-425: The blue to near-UV have also been used in place of light-emitting diodes (LEDs) to excite fluorescence as a white light source; this permits a much smaller emitting area due to the much greater radiance of a laser and avoids the droop suffered by LEDs; such devices are already used in some car headlamps . The first device using amplification by stimulated emission operated at microwave frequencies, and
10043-478: The case of medical devices, drugs, biological products, and other items where it may be difficult to conduct a physical examination or take a physical sample of the product. The Office of Regulatory Affairs is divided into five regions, which are further divided into 20 districts. The districts are based roughly on the geographic divisions of the Federal court system . Each district comprises a main district office and
10164-511: The contexts varying from household pets to human sperm donated for use in assisted reproduction . The FDA is led by the commissioner of Food and Drugs , appointed by the President with the advice and consent of the Senate . The commissioner reports to the secretary of health and human services . Robert Califf is the current commissioner as of February 17, 2022. The FDA's headquarters
10285-427: The discontinued Today sponge, and her rationing them based on whether a potential partner was "sponge-worthy". This was later revisited in the series finale when the pharmacist testifies against Elaine for buying a case of sponges. Food and Drug Administration The United States Food and Drug Administration ( FDA or US FDA ) is a federal agency of the Department of Health and Human Services . The FDA
10406-469: The drug in question is a prescription drug or an over-the-counter (OTC) drug. The FDA oversees the advertising of prescription drugs, while the FTC regulates the advertising of OTC drugs. The term off-label refers to the practice of prescribing a drug for a different purpose than what the FDA approved. Due to this approval requirement, manufacturers were prohibited from advertising COVID-19 vaccines during
10527-416: The drug is used safely. For example, thalidomide can cause birth defects, but has uses that outweigh the risks if men and women taking the drugs do not conceive a child; a REMS program for thalidomide mandates an auditable process to ensure that people taking the drug take action to avoid pregnancy; many opioid drugs have REMS programs to avoid addiction and diversion of drugs. The drug isotretinoin has
10648-696: The early 1990s, the U.S. Securities and Exchange Commission filed securities fraud charges against the Bolar Pharmaceutical Company, a major generic manufacturer based in Long Island, New York. Over-the-counter (OTC) are drugs like aspirin that do not require a doctor's prescription. The FDA has a list of approximately 800 such approved ingredients that are combined in various ways to create more than 100,000 OTC drug products. Many OTC drug ingredients had been previously approved prescription drugs now deemed safe enough for use without
10769-561: The effect of nonlinearity in optical materials (e.g. in second-harmonic generation , parametric down-conversion , optical parametric oscillators and the like). Unlike the giant pulse of a Q-switched laser, consecutive pulses from a mode-locked laser are phase-coherent; that is, the pulses (and not just their envelopes ) are identical and perfectly periodic. For this reason, and the extremely large peak powers attained by such short pulses, such lasers are invaluable in certain areas of research. Another method of achieving pulsed laser operation
10890-579: The entire manufacturing operation to American Home Products , now Wyeth . Almost the entire content of the facility was moved to the Whitehall-Robbins facility in Hammonton, New Jersey , from its original California home. The sponge was removed from the U.S. market in 1994 after problems were found at the facility related to the deionized water system. The water system, which was originally sized for much larger production, could not produce
11011-648: The federal agency resulted in racketeering and in violations of antitrust law . "The order in which new generic drugs were approved was set by the FDA employees even before drug manufacturers submitted applications" and, according to Mylan, this illegal procedure was followed to give preferential treatment to certain companies. During the summer of 1989, three FDA officials (Charles Y. Chang, David J. Brancato, Walter Kletch) pleaded guilty to criminal charges of accepting bribes from generic drugs makers, and two companies ( Par Pharmaceutical and its subsidiary Quad Pharmaceuticals) pleaded guilty to giving bribes. Furthermore, it
11132-436: The federal government. It helps support "partner" agencies and organisations prepare for public health emergencies that could require MCMs. The Center for Drug Evaluation and Research uses different requirements for the three main drug product types: new drugs, generic drugs, and over-the-counter drugs. A drug is considered "new" if it is made by a different manufacturer, uses different excipients or inactive ingredients,
11253-552: The first demonstration of stimulated emission. In 1950, Alfred Kastler (Nobel Prize for Physics 1966) proposed the method of optical pumping , which was experimentally demonstrated two years later by Brossel, Kastler, and Winter. In 1951, Joseph Weber submitted a paper on using stimulated emissions to make a microwave amplifier to the June 1952 Institute of Radio Engineers Vacuum Tube Research Conference in Ottawa , Ontario, Canada. After this presentation, RCA asked Weber to give
11374-555: The issuance of enforcement letters to pharmaceutical manufacturers. Advertising and promotion for over-the-counter drugs is regulated by the Federal Trade Commission . The FDA also implements regulatory oversight through engagement with third-party enforcer-firms. It expects pharmaceutical companies to ensure that third-party suppliers and labs comply with the agency's health and safety guidelines . The drug advertising regulation contains two broad requirements: (1)
11495-422: The laser power inside the cavity; this equilibrium determines the operating point of the laser. If the applied pump power is too small, the gain will never be sufficient to overcome the cavity losses, and laser light will not be produced. The minimum pump power needed to begin laser action is called the lasing threshold . The gain medium will amplify any photons passing through it, regardless of direction; but only
11616-501: The lasing medium or pumping mechanism, then it is still classified as a "modulated" or "pulsed" continuous wave laser. Most laser diodes used in communication systems fall into that category. Some applications of lasers depend on a beam whose output power is constant over time. Such a laser is known as a continuous-wave ( CW ) laser. Many types of lasers can be made to operate in continuous-wave mode to satisfy such an application. Many of these lasers lase in several longitudinal modes at
11737-414: The latter case, the photon is emitted in the same direction as the light that is passing by. When the number of particles in one excited state exceeds the number of particles in some lower-energy state, population inversion is achieved. In this state, the rate of stimulated emission is larger than the rate of absorption of light in the medium, and therefore the light is amplified. A system with this property
11858-509: The linewidth of light emitted from the passive resonator. Some lasers use a separate injection seeder to start the process off with a beam that is already highly coherent. This can produce beams with a narrower spectrum than would otherwise be possible. In 1963, Roy J. Glauber showed that coherent states are formed from combinations of photon number states, for which he was awarded the Nobel Prize in physics . A coherent beam of light
11979-402: The literal cavity that would be employed at microwave frequencies in a maser . The resonator typically consists of two mirrors between which a coherent beam of light travels in both directions, reflecting on itself so that an average photon will pass through the gain medium repeatedly before it is emitted from the output aperture or lost to diffraction or absorption. If the gain (amplification) in
12100-522: The lower level, emitting a new photon. The emitted photon exactly matches the original photon in wavelength, phase, and direction. This process is called stimulated emission. The gain medium is put into an excited state by an external source of energy. In most lasers, this medium consists of a population of atoms that have been excited into such a state using an outside light source, or an electrical field that supplies energy for atoms to absorb and be transformed into their excited states. The gain medium of
12221-412: The maximum possible level, the introduced loss mechanism (often an electro- or acousto-optical element) is rapidly removed (or that occurs by itself in a passive device), allowing lasing to begin which rapidly obtains the stored energy in the gain medium. This results in a short pulse incorporating that energy, and thus a high peak power. A mode-locked laser is capable of emitting extremely short pulses on
12342-498: The medium is larger than the resonator losses, then the power of the recirculating light can rise exponentially . But each stimulated emission event returns an atom from its excited state to the ground state, reducing the gain of the medium. With increasing beam power, the net gain (gain minus loss) reduces to unity and the gain medium is said to be saturated. In a continuous wave (CW) laser, the balance of pump power against gain saturation and cavity losses produces an equilibrium value of
12463-404: The object is not random, however: it is stored by atoms and molecules in " excited states ", which release photons with distinct wavelengths. This gives rise to the science of spectroscopy , which allows materials to be determined through the specific wavelengths that they emit. The underlying physical process creating photons in a laser is the same as in thermal radiation, but the actual emission
12584-456: The order of tens of picoseconds down to less than 10 femtoseconds . These pulses repeat at the round-trip time, that is, the time that it takes light to complete one round trip between the mirrors comprising the resonator. Due to the Fourier limit (also known as energy–time uncertainty ), a pulse of such short temporal length has a spectrum spread over a considerable bandwidth. Thus such
12705-533: The period in which they had only been approved under Emergency Use Authorization . After NDA approval, the sponsor must then review and report to the FDA every single patient adverse drug experience it learns of. They must report unexpected serious and fatal adverse drug events within 15 days, and other events on a quarterly basis. The FDA also receives directly adverse drug event reports through its MedWatch program. These reports are called "spontaneous reports" because reporting by consumers and health professionals
12826-418: The photons in a spatial mode supported by the resonator will pass more than once through the medium and receive substantial amplification. In most lasers, lasing begins with spontaneous emission into the lasing mode. This initial light is then amplified by stimulated emission in the gain medium. Stimulated emission produces light that matches the input signal in direction, wavelength, and polarization, whereas
12947-409: The power output is essentially continuous over time or whether its output takes the form of pulses of light on one or another time scale. Of course, even a laser whose output is normally continuous can be intentionally turned on and off at some rate to create pulses of light. When the modulation rate is on time scales much slower than the cavity lifetime and the period over which energy can be stored in
13068-422: The predicate devices already on the market. Approved requests are for items that are new or substantially different and need to demonstrate "safety and efficacy", for example they may be inspected for safety in case of new toxic hazards. Both aspects need to be proved or provided by the submitter to ensure proper procedures are followed. Cosmetics are regulated by the Center for Food Safety and Applied Nutrition ,
13189-662: The properties of the emitted light, such as the polarization, wavelength, and shape of the beam. Electrons and how they interact with electromagnetic fields are important in our understanding of chemistry and physics . In the classical view , the energy of an electron orbiting an atomic nucleus is larger for orbits further from the nucleus of an atom . However, quantum mechanical effects force electrons to take on discrete positions in orbitals . Thus, electrons are found in specific energy levels of an atom, two of which are shown below: An electron in an atom can absorb energy from light ( photons ) or heat ( phonons ) only if there
13310-580: The regulated industries. Rather, OCI agents pursue and develop cases when individuals and companies commit criminal actions, such as fraudulent claims or knowingly and willfully shipping known adulterated goods in interstate commerce. In many cases, OCI pursues cases involving violations of Title 18 of the United States Code (e.g., conspiracy, false statements, wire fraud, mail fraud), in addition to prohibited acts as defined in Chapter III of
13431-470: The regulatory powers granted to the agency. For example, the FDA regulates almost every facet of prescription drugs, including testing, manufacturing, labeling, advertising, marketing, efficacy, and safety—yet FDA regulation of cosmetics focuses primarily on labeling and safety. The FDA regulates most products with a set of published standards enforced by a modest number of facility inspections. Inspection observations are documented on Form 483 . In June 2018,
13552-457: The relationship between the A coefficient , describing spontaneous emission, and the B coefficient which applies to absorption and stimulated emission. In the case of the free electron laser , atomic energy levels are not involved; it appears that the operation of this rather exotic device can be explained without reference to quantum mechanics . A laser can be classified as operating in either continuous or pulsed mode, depending on whether
13673-448: The safety and labeling of their product. The FDA has a "Dietary Supplement Ingredient Advisory List" that includes ingredients that sometimes appear on dietary supplements but need further evaluation. An ingredient is added to this list when it is excluded from use in a dietary supplement, does not appear to be an approved food additive or recognized as safe, and/or is subjected to the requirement for pre-market notification without having
13794-458: The same branch of the FDA that regulates food. Cosmetic products are not, in general, subject to premarket approval by the FDA unless they make "structure or function claims" that make them into drugs (see Cosmeceutical ). However, all color additives must be specifically FDA approved before manufacturers can include them in cosmetic products sold in the U.S. The FDA regulates cosmetics labeling, and cosmetics that have not been safety tested must bear
13915-410: The same time, and beats between the slightly different optical frequencies of those oscillations will produce amplitude variations on time scales shorter than the round-trip time (the reciprocal of the frequency spacing between modes), typically a few nanoseconds or less. In most cases, these lasers are still termed "continuous-wave" as their output power is steady when averaged over longer periods, with
14036-438: The small amounts of deionized water required for this one product and became repeatedly contaminated. Based on slumping sales and to avoid any further FDA issues, Wyeth stopped selling the sponge rather than move production or modify its plant. In 1998, Allendale Pharmaceuticals acquired the rights to the Today sponge and it was once again available. New FDA standards for manufacturing and record-keeping forced repeated delays, but
14157-425: The two mirrors, the output coupler , is partially transparent. Some of the light escapes through this mirror. Depending on the design of the cavity (whether the mirrors are flat or curved ), the light coming out of the laser may spread out or form a narrow beam . In analogy to electronic oscillators , this device is sometimes called a laser oscillator . Most practical lasers contain additional elements that affect
14278-410: The very high-frequency power variations having little or no impact on the intended application. (However, the term is not applied to mode-locked lasers, where the intention is to create very short pulses at the rate of the round-trip time.) For continuous-wave operation, the population inversion of the gain medium needs to be continually replenished by a steady pump source. In some lasing media, this
14399-598: Was called a maser , for "microwave amplification by stimulated emission of radiation". When similar optical devices were developed they were first called optical masers , until "microwave" was replaced by "light" in the acronym, to become laser . Today, all such devices operating at frequencies higher than microwaves (approximately above 300 GHz ) are called lasers (e.g. infrared lasers , ultraviolet lasers , X-ray lasers , gamma-ray lasers ), whereas devices operating at microwave or lower radio frequencies are called masers. The back-formed verb " to lase "
14520-533: Was discovered that several manufacturers had falsified data submitted in seeking FDA authorization to market certain generic drugs. Vitarine Pharmaceuticals of New York, which sought approval of a generic version of the drug Dyazide , a medication for high blood pressure, submitted Dyazide, rather than its generic version, for the FDA tests. In April 1989, the FDA investigated 11 manufacturers for irregularities; and later brought that number up to 13. Dozens of drugs were eventually suspended or recalled by manufacturers. In
14641-543: Was established by the 1902 Biologics Control Act , with additional authority established by the 1944 Public Health Service Act . Along with these Acts, the Federal Food, Drug, and Cosmetic Act applies to all biologic products, as well. Originally, the entity responsible for regulation of biological products resided under the National Institutes of Health ; this authority was transferred to the FDA in 1972. The Center for Devices and Radiological Health (CDRH)
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