Los Angeles the City of Los Angeles and known by its initials L. A. is the most populous city in California, the second most populous city in the United States, after New York City, the third most populous city in North America. With an estimated population of four million, Los Angeles is the cultural and commercial center of Southern California; the city is known for its Mediterranean climate, ethnic diversity and the entertainment industry, its sprawling metropolis. Los Angeles is the largest city on the West Coast of North America. Los Angeles is in a large basin bounded by the Pacific Ocean on one side and by mountains as high as 10,000 feet on the other; the city proper, which covers about 469 square miles, is the seat of Los Angeles County, the most populated county in the country. Los Angeles is the principal city of the Los Angeles metropolitan area, the second largest in the United States after that of New York City, with a population of 13.1 million. It is part of the Los Angeles-Long Beach combined statistical area the nation's second most populous area with a 2015 estimated population of 18.7 million.
Los Angeles is one of the most substantial economic engines within the United States, with a diverse economy in a broad range of professional and cultural fields. Los Angeles is famous as the home of Hollywood, a major center of the world entertainment industry. A global city, it has been ranked 6th in the Global Cities Index and 9th in the Global Economic Power Index; the Los Angeles metropolitan area has a gross metropolitan product of $1.044 trillion, making it the third-largest in the world, after the Tokyo and New York metropolitan areas. Los Angeles hosted the 1932 and 1984 Summer Olympics and will host the event for a third time in 2028; the city hosted the Miss Universe pageant twice, in 1990 and 2006, was one of 9 American cities to host the 1994 FIFA men's soccer World Cup and one of 8 to host the 1999 FIFA women's soccer World Cup, hosting the final match for both tournaments. Home to the Chumash and Tongva, Los Angeles was claimed by Juan Rodríguez Cabrillo for Spain in 1542 along with the rest of what would become Alta California.
The city was founded on September 4, 1781, by Spanish governor Felipe de Neve. It became a part of Mexico in 1821 following the Mexican War of Independence. In 1848, at the end of the Mexican–American War, Los Angeles and the rest of California were purchased as part of the Treaty of Guadalupe Hidalgo, becoming part of the United States. Los Angeles was incorporated as a municipality on April 4, 1850, five months before California achieved statehood; the discovery of oil in the 1890s brought rapid growth to the city. The completion of the Los Angeles Aqueduct in 1913, delivering water from Eastern California assured the city's continued rapid growth; the Los Angeles coastal area was settled by the Chumash tribes. A Gabrieleño settlement in the area was called iyáangẚ, meaning "poison oak place". Maritime explorer Juan Rodríguez Cabrillo claimed the area of southern California for the Spanish Empire in 1542 while on an official military exploring expedition moving north along the Pacific coast from earlier colonizing bases of New Spain in Central and South America.
Gaspar de Portolà and Franciscan missionary Juan Crespí, reached the present site of Los Angeles on August 2, 1769. In 1771, Franciscan friar Junípero Serra directed the building of the Mission San Gabriel Arcángel, the first mission in the area. On September 4, 1781, a group of forty-four settlers known as "Los Pobladores" founded the pueblo they called El Pueblo de Nuestra Señora la Reina de los Ángeles,'The Town of Our Lady the Queen of the Angels'; the present-day city has the largest Roman Catholic Archdiocese in the United States. Two-thirds of the Mexican or settlers were mestizo or mulatto, a mixture of African and European ancestry; the settlement remained a small ranch town for decades, but by 1820, the population had increased to about 650 residents. Today, the pueblo is commemorated in the historic district of Los Angeles Pueblo Plaza and Olvera Street, the oldest part of Los Angeles. New Spain achieved its independence from the Spanish Empire in 1821, the pueblo continued as a part of Mexico.
During Mexican rule, Governor Pío Pico made Los Angeles Alta California's regional capital. Mexican rule ended during the Mexican–American War: Americans took control from the Californios after a series of battles, culminating with the signing of the Treaty of Cahuenga on January 13, 1847. Railroads arrived with the completion of the transcontinental Southern Pacific line to Los Angeles in 1876 and the Santa Fe Railroad in 1885. Petroleum was discovered in the city and surrounding area in 1892, by 1923, the discoveries had helped California become the country's largest oil producer, accounting for about one-quarter of the world's petroleum output. By 1900, the population had grown to more than 102,000; the completion of the Los Angeles Aqueduct in 1913, under the supervision of William Mulholland, assured the continued growth of the city. Due to clauses in the city's charter that prevented the City of Los Angeles from selling or providing water from the aqueduct to any area outside its borders, many adjacent city and communities became compelled to annex themselves into Los Angeles.
Los Angeles created the first municipal zoning ordinance in the United States. On September 14, 1908, the Los Angeles City Council promulgated residential and industrial land use zones; the new ordinance established three residential zones of a single type, where industrial uses were
Health policy can be defined as the "decisions and actions that are undertaken to achieve specific healthcare goals within a society". According to the World Health Organization, an explicit health policy can achieve several things: it defines a vision for the future. There are many categories of health policies, including global health policy, public health policy, mental health policy, health care services policy, insurance policy, personal healthcare policy, pharmaceutical policy, policies related to public health such as vaccination policy, tobacco control policy or breastfeeding promotion policy, they may cover topics of financing and delivery of healthcare, access to care, quality of care, health equity. Health-related policy and its implementation is complex. Conceptual models can help show the flow from health-related policy development to health-related policy and program implementation and to health systems and health outcomes. Policy should be understood as more than a national law or health policy that supports a program or intervention.
Operational policies are the rules, regulations and administrative norms that governments use to translate national laws and policies into programs and services. The policy process encompasses decisions made at a national or decentralized level that affect whether and how services are delivered. Thus, attention must be paid to policies at multiple levels of the health system and over time to ensure sustainable scale-up. A supportive policy environment will facilitate the scale-up of health interventions. There are many topics in the politics and evidence that can influence the decision of a government, private sector business or other group to adopt a specific policy. Evidence-based policy relies on the use of science and rigorous studies such as randomized controlled trials to identify programs and practices capable of improving policy relevant outcomes. Most political debates surround personal health care policies those that seek to reform healthcare delivery, can be categorized as either philosophical or economic.
Philosophical debates center around questions about individual rights and government authority, while economic topics include how to maximize the efficiency of health care delivery and minimize costs. The modern concept of healthcare involves access to medical professionals from various fields as well as medical technology, such as medications and surgical equipment, it involves access to the latest information and evidence from research, including medical research and health services research. In many countries it is left to the individual to gain access to healthcare goods and services by paying for them directly as out-of-pocket expenses, to private sector players in the medical and pharmaceutical industries to develop research. Planning and production of health human resources is distributed among labour market participants. Other countries have an explicit policy to ensure and support access for all of its citizens, to fund health research, to plan for adequate numbers and quality of health workers to meet healthcare goals.
Many governments around the world have established universal health care, which takes the burden of healthcare expenses off of private businesses or individuals through pooling of financial risk. There are a variety of arguments against universal healthcare and related health policies. Healthcare is an important part of health systems and therefore it accounts for one of the largest areas of spending for both governments and individuals all over the world. Many countries and jurisdictions integrate a human rights philosophy in directing their healthcare policies; the World Health Organization reports that every country in the world is party to at least one human rights treaty that addresses health-related rights, including the right to health as well as other rights that relate to conditions necessary for good health. The United Nations' Universal Declaration of Human Rights asserts that medical care is a right of all people: UDHR Article 25: "Everyone has the right to a standard of living adequate for the health and well-being of himself and of his family, including food, clothing and medical care and necessary social services, the right to security in the event of unemployment, disability, old age or other lack of livelihood in circumstances beyond his control."In some jurisdictions and among different faith-based organizations, health policies are influenced by the perceived obligation shaped by religious beliefs to care for those in less favorable circumstances, including the sick.
Other jurisdictions and non-governmental organizations draw on the principles of humanism in defining their health policies, asserting the same perceived obligation and enshrined right to health. In recent years, the worldwide human rights organization Amnesty International has focused on health as a human right, addressing inadequate access to HIV drugs and women's sexual and reproductive rights including wide disparities in maternal mortality within and across countries; such increasing attention to health as a basic human right has been welcomed by the leading medical journal The Lancet. There remains considerable controversy regarding policies on who would be paying the costs of medical care for all people and under what circumstances. For example, government spending on healthcare is sometimes used as a global indicator of a government's commitment to the health of its people. On the other hand, one school of thought emerging from the United States rejects the notion of health care financing through taxpayer funding as incompatible with the
David Geffen School of Medicine at UCLA
The University of California, Los Angeles School of Medicine—known as the David Geffen School of Medicine at UCLA —is an accredited medical school located in Los Angeles, California, USA. The School was renamed in 2001 in honor of media mogul David Geffen who donated $200 million in unrestricted funds. Founded in 1951, it was the second medical school in the UC system, after the UCSF School of Medicine. At its incorporation in 1873, the UCSF School of Medicine was the only medical school in the University of California; the UC Board of Regents voted to establish a medical school affiliated with UCLA in 1945. In 1947, Stafford L. Warren was appointed as the first dean. Dr. Warren had served on the Manhattan Project while on leave from his post at University of Rochester School of Medicine; as the founding dean of the medical school, he proved to be a capable fundraiser. His choice of core faculty consisted of his former associates at Rochester in Andrew Dowdy as the first professor of radiology, John Lawrence as the first professor of medicine, Charles Carpenter as the first professor of infectious diseases.
Along with William Longmire Jr. a promising 34-year-old surgeon from Johns Hopkins, the group was called the Founding Five. Building of the medical center and the School of Medicine began in 1949; the 1951 charter class consisted of 2 women. There were 15 faculty members, although that number had increased to 43 by 1955 when the charter class graduated; the first classes were conducted in the reception lounge of the old Religious Conference Building on Le Conte Avenue. In July 1955, the UCLA Medical Center was opened. Sherman Mellinkoff served for the next 24 years. Under Dr. Mellinkoff, the school experienced unprecedented growth; the UCLA Neuropsychiatric Institute, the UCLA Brain Research Institute, the Marion Davies Children's Center were founded. The Jules Stein Eye Institute and the Reed Neurological Research Center were established as well. By decade's end UCLA had doubled the size of the hospital; the UCLA School of Dentistry, School of Public Health, School of Nursing were formed as well.
The medical school grew to nearly 400 medical students, more than 700 interns and residents, 200 Masters and doctorate candidates. A partnership was formed with the Charles R. Drew University of Medicine and Science in 1966 to train medical students with the goal of meeting the needs of the underserved in South Los Angeles; the school continued its growth in the 1970s, becoming affiliated with VA facilities as well as Olive View–UCLA Medical Center. In 1974, the school co-founded the Biomedical Sciences Program with UC Riverside that offers 24 students each year the opportunity to earn both the B. S. and M. D. degrees in seven years instead of the traditional eight. 1981 saw the dedication of the Doris and Louis Factor Health Sciences Building which houses the School of Nursing and Jonsson Comprehensive Cancer Center. In 1987, construction began on UCLA Medical Plaza, an outpatient facility located across the street from the main hospital. Kenneth I. Shine succeeded Sherman Mellinkoff as dean in 1986.
In 1992 Dr. Shine left UCLA to become President of the Institute of Medicine in Washington, D. C. Gerald S. Levey was appointed provost of medical sciences and dean of the medical school in 1994. Dr. Levey oversaw expansion of interdisciplinary research and the establishment of a Department of Human Genetics. Under his leadership the Gonda Neuroscience and Genetics Research Center as well as the Ronald Reagan UCLA Medical Center, ranked "Best in the West" by US News & World Report, were constructed. In October 2008, Dr. Levey announced that he would be stepping down from the position of Dean in 2009. Effective February 2010, Dr. A. Eugene Washington was appointed Dean of the UCLA School of Medicine and Vice Chancellor of Health Sciences at UCLA. Dr. Washington, a noted clinician, academician and university administrator, was recruited from UCSF, where he served as Vice Chancellor and Provost, as well as Professor of gynecology and health policy. Dr. Washington is the first-ever African-American to hold these leadership posts at UCLA.
UCLA constructed the Ronald Reagan UCLA Medical Center across the street from the original facility to comply with the California earthquake law. The 1,050,000-square-foot hospital is named after the late President of the United States and Governor of California, Ronald Reagan, it was designed by Pritzker Prize-winning architect I. M. Pei. Patients were transferred there from the existing hospital in June 2008. In the rankings released for 2015, U. S. News & World Report ranked David Geffen School of Medicine at UCLA at No. 12 in the U. S. in research and for 2013-2014 ranked UCLA Medical Center at No. 5. The Geffen School of Medicine has an acceptance rate of 4.5%, rendering it to be one of the most competitive medical schools in the country. The David Geffen School of Medicine at UCLA accepts applications for summer academic enrichment programs; these programs include the Premedical/Predental Enrichment Program, Summer Medical Dental Education Program, the Re-Application Post baccalaureate Program.
Application deadlines are March 1 for the PREP and SMDEP programs, while the RAP program has a deadline of May 15. Arie S. Belldegrun, MD, FACS, is a director of the UCLA Institute of Urologic Oncology and is Professor and Chief of Urologic Oncology at the David Geffen School of Medicine, he holds the Carol Doumani Chair in Urologic Oncology. He is the Clinical Director of the UCLA Prostate Disease Research Program and Surgical Director of the UCLA Kidney Cancer Program. Ronald W. Busuttil, MD, PhD is the Chairman of the Department of Surgery, Chi
University of California, Los Angeles
The University of California, Los Angeles is a public research university in Los Angeles. It became the Southern Branch of the University of California in 1919, making it the third-oldest undergraduate campus of the 10-campus University of California system, it offers 337 graduate degree programs in a wide range of disciplines. UCLA enrolls about 31,000 undergraduate and 13,000 graduate students and had 119,000 applicants for Fall 2016, including transfer applicants, making the school the most applied-to of any American university; the university is organized into six undergraduate colleges, seven professional schools, four professional health science schools. The undergraduate colleges are the College of Science; as of 2017, 24 Nobel laureates, three Fields Medalists, five Turing Award winners, two Chief Scientists of the U. S. Air Force have been affiliated with UCLA as researchers, or alumni. Among the current faculty members, 55 have been elected to the National Academy of Sciences, 28 to the National Academy of Engineering, 39 to the Institute of Medicine, 124 to the American Academy of Arts and Sciences.
The university was elected to the Association of American Universities in 1974. UCLA is considered one of the country's Public Ivies, meaning that it is a public university thought to provide a quality of education comparable with that of the Ivy League. In 2018, US News & World Report named UCLA the best public university in the United States. UCLA student-athletes compete as the Bruins in the Pac-12 Conference; the Bruins have won 126 national championships, including 116 NCAA team championships, more than any other university except Stanford, who has won 117. UCLA student-athletes and staff won 251 Olympic medals: 126 gold, 65 silver, 60 bronze. UCLA student-athletes competed in every Olympics since 1920 with one exception and won a gold medal in every Olympics the U. S. participated in since 1932. In March 1881, the California State Legislature authorized the creation of a southern branch of the California State Normal School in downtown Los Angeles to train teachers for the growing population of Southern California.
The Los Angeles branch of the California State Normal School opened on August 29, 1882, on what is now the site of the Central Library of the Los Angeles Public Library system. The facility included an elementary school where teachers-in-training could practice their technique with children; that elementary school is related to the present day UCLA Lab School. In 1887, the branch campus became independent and changed its name to Los Angeles State Normal School. In 1914, the school moved to a new campus on Vermont Avenue in East Hollywood. In 1917, UC Regent Edward Augustus Dickson, the only regent representing the Southland at the time, Ernest Carroll Moore, Director of the Normal School, began to lobby the State Legislature to enable the school to become the second University of California campus, after UC Berkeley, they met resistance from UC Berkeley alumni, Northern California members of the state legislature, Benjamin Ide Wheeler, President of the University of California from 1899 to 1919, who were all vigorously opposed to the idea of a southern campus.
However, David Prescott Barrows, the new President of the University of California, did not share Wheeler's objections. On May 23, 1919, the Southern Californians' efforts were rewarded when Governor William D. Stephens signed Assembly Bill 626 into law, which transformed the Los Angeles Normal School into the Southern Branch of the University of California; the same legislation added the College of Letters and Science. The Southern Branch campus opened on September 15 of that year, offering two-year undergraduate programs to 250 Letters and Science students and 1,250 students in the Teachers College, under Moore's continued direction. Under University of California President William Wallace Campbell, enrollment at the Southern Branch expanded so that by the mid-1920s the institution was outgrowing the 25 acre Vermont Avenue location; the Regents searched for a new location and announced their selection of the so-called "Beverly Site"—just west of Beverly Hills—on March 21, 1925 edging out the panoramic hills of the still-empty Palos Verdes Peninsula.
After the athletic teams entered the Pacific Coast conference in 1926, the Southern Branch student council adopted the nickname "Bruins", a name offered by the student council at UC Berkeley. In 1927, the Regents renamed the Southern Branch the University of California at Los Angeles. In the same year, the state broke ground in Westwood on land sold for $1 million, less than one-third its value, by real estate developers Edwin and Harold Janss, for whom the Janss Steps are named; the campus in Westwood opened to students in 1929. The original four buildings were the College Library, Royce Hall, the Physics-Biology Building, the Chemistry Building, arrayed around a quadrangular courtyard on the 400 acre campus; the first undergraduate classes on the new campus were held in 1929 with 5,500 students. After lobbying by alumni, faculty and community leaders, UCLA was permitted to award the master's degree in 1933, the doctorate in 1936, against continued resistance from UC Berkeley. A timeline of the history can be found on its website, as well
UCLA Anderson School of Management
The UCLA Anderson School of Management is the graduate business school at the University of California, Los Angeles, one of eleven professional schools. The school offers MBA, PGPX, Financial Engineering and Ph. D. degrees. The school is ranked among the top tier business school programs in the country, based on rankings published by US News & World Report and other leading publications; the range of programs offered by Anderson includes: Accounting minor for undergraduates Full Time MBA program Ph. D. Employed MBA Executive MBA Master of Financial Engineering Master of Science in Business Analytics Global EMBA for Asia Pacific Global EMBA for the Americas Post Graduate Program in Management for Executives Post Graduate Program in Management for Professionals The School of Management at UCLA was founded in 1935, the MBA degree was authorized by the UC Regents four years later. In its early years the school was an undergraduate institution, although this began to change in the 1950s after the appointment of Neil H. Jacoby as dean.
UCLA is rare among public universities in the U. S. for not offering undergraduate business administration degrees. Undergraduate degrees in business economics are offered. In 1950, the school was renamed the School of Business Administration. Five years it became the Graduate School of Business Administration. In 1987, John E. Anderson, class of 1940, donated $15 million to the school and prompted the construction of a new complex at the north end of UCLA’s campus, he donated additional $25 million. The 6-building, 285,000-square-foot facility, was designed by Henry N. Cobb of the architectural firm Pei Cobb Freed & Partners and Executive Architects Leidenfrost/Horowitz & Associates, it cost $75 million to construct and opened in 1995. On May 13, 2015, Marion Anderson, widow of the late John Anderson, announced a $100 million donation to the school for fellowships and research, along with $40 million earmarked for initiating development of what is now known as the Marion Anderson Hall; the school has been self-funded, with only $6 million of government funding out of its $96 million budget in 2010-11.
In fall 2010, the school proposed "financial self-sufficiency": Giving up all state funding, in return for freedom from some state rules and freedom to raise tuition. Critics called this proposal "privatization", but the school rejected this description, with former Dean Judy Olian saying, "This is not privatization.... We will continue to be part of UCLA and part of the state." The proposal met objections in the UCLA Academic Senate, is still pending. Update: This decision was approved by the University of California President Mark Yudof in June 2013. In July 2018, Judy D. Olian, who served as dean of UCLA's Anderson School of Management, became Quinnipiac's first female president when she took over for John Lahey, who retired in June 2018. Alfred Osborne, associate senior dean of external affairs and a professor at the UCLA Anderson School of Management, began serving as the school’s interim dean on July 1, 2018; the school is located on north part of the UCLA campus. The four main buildings, Cornell and Gold, form an inner circle at the corner of Sunset Boulevard and Westwood Plaza, the extension of Westwood Boulevard.
Connected to the Gold building is the Collins building, named for alumnus James A. Collins, the chairman emeritus of Sizzler International, Inc. and who funded the John R. Wooden statue in front of Pauley Pavilion. On October 19, 2017, the new Marion Anderson Hall addition broke ground; the 64,000 square-foot campus addition is estimated to cost $80 million and is one hundred percent donor-funded. Marion Anderson Hall is designed by the same architectural firm that designed the original Anderson complex: Pei Cobb Freed & Partners. Scheduled to open at the end of 2019, the new building features four floors, interactive work spaces, LEED Gold certification, will serve as the prominent entrance to the Anderson complex; as of 2011, UCLA Anderson enrolls 70 executive MBA, 90 global MBA, 280 employed MBA, 360 full-time MBA students every year. UCLA Anderson’s teaching model combines case study, experiential learning and team projects. UCLA Anderson's curriculum consists of twelve elective courses. Students are assigned to cohorts, called sections, of 65 students throughout the core curriculum.
The cohort system is entirely student run, with each cohort electing 17 different leadership positions ranging from President to Ethics chair. In addition, there is the student-led Anderson Student Association which deals with all issues of student life including company recruiting, social clubs and academic issues. Students may choose to focus in one or more of the following areas: Accounting Decisions and Technology Management Communications and Entertainment Management Entrepreneurial Studies Finance Global Economics and Management Human Resources and Organizational Behavior Information Systems Marketing Policy Real EstateAnderson offers an Applied Management Research Program, consisting of a two-quarter team-based strategic consulting field study project required during the second year of study in lieu of the comprehensive exam for the master's degree. Students complete strategic projects for comp
Toxicology is a discipline, overlapping with biology, chemistry and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating exposures to toxins and toxicants. The relationship between dose and its effects on the exposed organism is of high significance in toxicology. Factors that influence chemical toxicity include the dosage, route of exposure, age and environment. Toxicologists are experts on poisons and poisoning. Dioscorides, a Greek physician in the court of the Roman emperor Nero, made the first attempt to classify plants according to their toxic and therapeutic effect. Ibn Wahshiyya wrote the Book on Poisons in the 10th century; this was followed up in 1360 by Khagendra Mani Darpana. Mathieu Orfila is considered the modern father of toxicology, having given the subject its first formal treatment in 1813 in his Traité des poisons called Toxicologie générale. In 1850, Jean Stas became the first person to isolate plant poisons from human tissue.
This allowed him to identify the use of nicotine as a poison in the famous Bocarmé murder case, providing the evidence needed to convict the Belgian Count Hippolyte Visart de Bocarmé of killing his brother-in-law. Theophrastus Phillipus Auroleus Bombastus von Hohenheim is considered "the father" of toxicology, he is credited with the classic toxicology maxim, "Alle Dinge sind. This is condensed to: "The dose makes the poison" or in Latin "Sola dosis facit venenum"; the goal of toxicity assessment is to identify adverse effects of a substance. Adverse effects depend on two main factors: i) routes of exposure and ii) dose. To explore dose, substances are tested in both chronic models. Different sets of experiments are conducted to determine whether a substance causes cancer and to examine other forms of toxicity. Factors that influence chemical toxicity: Dosage Both large single exposures and continuous small exposures are studied. Route of exposure Ingestion, inhalation or skin absorption Other factors Species Age Sex Health Environment Individual characteristics Toxicity experiments may be conducted in vivo or in vitro, or in silico.
The classic experimental tool of toxicology is testing on non-human animals. Example of model organisms are Galleria mellonella, which can replace small mammals, Zebrafish, which allow for the study of toxicology in a lower order vertebrate in vivo; as of 2014, such animal testing provides information, not available by other means about how substances function in a living organism. The use of non-human animals for toxicology testing is opposed by some organisations for reasons of animal welfare, it has been restricted or banned under some circumstances in certain regions, such as the testing of cosmetics in the European Union. While testing in animal models remains as a method of estimating human effects, there are both ethical and technical concerns with animal testing. Since the late 1950s, the field of toxicology has sought to reduce or eliminate animal testing under the rubric of "Three Rs" - reduce the number of experiments with animals to the minimum necessary. Computer modeling is an example of alternative testing methods.
This work requires expert knowledge in molecular modeling and statistics together with expert judgment in chemistry and toxicology. In 2007 the American NGO National Academy of Sciences published a report called "Toxicity Testing in the 21st Century: A Vision and a Strategy" which opened with a statement: "Change involves a pivotal event that builds on previous history and opens the door to a new era. Pivotal events in science include the discovery of penicillin, the elucidation of the DNA double helix, the development of computers.... Toxicity testing is approaching such a scientific pivot point, it is poised to take advantage of the revolutions in biotechnology. Advances in toxicogenomics, systems biology and computational toxicology could transform toxicity testing from a system based on whole-animal testing to one founded on in vitro methods that evaluate changes in biologic processes using cells, cell lines, or cellular components, preferably of human origin." As of 2014 that vision was still unrealized.
In some cases shifts away from animal studies has been mandated by regulation. Most chemicals display a classic dose response curve – at a low dose, no effect is observed; some show a phenomenon known as sufficient challenge – a small exposure produces animals that "grow more have better general appearance and coat quality, have fewer tumors, live longer than the control animals". A few chemicals have no well-defined safe level of exposure; these are treated with special