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Molecule Of The Year
The Breakthrough of the Year is an annual award for the most significant development in scientific research made by the AAAS journal ''Science,'' an academic journal covering all branches of science. Originating in 1989 as the ''Molecule of the Year'', and inspired by ''Time'' Person of the Year, it was renamed the Breakthrough of the Year in 1996. Molecule of the Year * 1989 PCR and DNA polymerase * 1990 the manufacture of synthetic diamonds * 1991 buckminsterfullerene * 1992 nitric oxide * 1993 p53 * 1994 DNA repair enzyme Breakthrough of the Year * 1996: Understanding HIV * 1997: Dolly the sheep, the first mammal to be cloned from adult cells * 1998: Accelerating universe * 1999: Prospective stem-cell therapies * 2000: Full genome sequencing * 2001: Nanocircuits or Molecular circuit * 2002: RNA interference * 2003: Dark energy * 2004: ''Spirit'' rover landed on Mars * 2005: Evolution in action * 2006: Proof of the Poincaré conjecture * 2007: Human genetic varia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Association For The Advancement Of Science
The American Association for the Advancement of Science (AAAS) is a United States–based international nonprofit with the stated mission of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting science education, scientific education and science outreach for the betterment of all humanity. AAAS was the first permanent organization established to promote science and engineering nationally and to represent the interests of American researchers from across all scientific fields. It is the world's largest general scientific society, with over 120,000 members, and is the publisher of the well-known scientific journal ''Science (journal), Science''. History Creation The American Association for the Advancement of Science was created on September 20, 1848, at the Academy of Natural Sciences in Philadelphia, Pennsylvania. It was a reformation of the Association of American Geologists and Naturalists with the broaden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanocircuits
Nanocircuits are electrical circuits operating on the nanometer scale where quantum mechanical effects become important. One nanometer is equal to 10−9 meters or a row of 10 hydrogen atoms. With such progressively smaller circuits, more can be fitted on a computer chip. This allows faster and more complex functions using less power. Nanocircuits are composed of three different fundamental components. These are transistors, interconnections, and architecture, all fabricated on the nanometer scale. Various approaches to nanocircuitry A variety of proposals have been made to implement nanocircuitry in different forms. These include Nanowires, Single-Electron Transistors, Quantum dot cellular automata, and Nanoscale Crossbar Latches. However, likely nearer-term approaches will involve incorporation of nanomaterials to improve MOSFETs (metal–oxide–semiconductor field-effect transistors). These currently form the basis of most analog and digital circuit designs, the sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Higgs Boson
The Higgs boson, sometimes called the Higgs particle, is an elementary particle in the Standard Model of particle physics produced by the excited state, quantum excitation of the Higgs field, one of the field (physics), fields in particle physics theory. In the Standard Model, the Higgs particle is a massive scalar boson that Coupling (physics), couples to (interacts with) particles whose mass arises from their interactions with the Higgs Field, has zero Spin (physics), spin, even (positive) Parity (physics), parity, no electric charge, and no color charge, colour charge. It is also very unstable, particle decay, decaying into other particles almost immediately upon generation. The Higgs field is a scalar field with two neutral and two electrically charged components that form a complex doublet (physics), doublet of the weak isospin SU(2) symmetry. Its "Spontaneous symmetry breaking#Sombrero potential, sombrero potential" leads it to take a nonzero value everywhere (inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HPTN 052
HPTN 052 is the name of a clinical trial conducted in nine countries which examined whether starting people living with HIV on antiretroviral therapy (ART) can reduce the chance that they will pass HIV on to their sexual partners who do not have HIV. The trial showed remarkable success in preventing HIV transmission and were so compelling that the study's Data and Safety Monitoring Board (DSMB) asked the research team to share the results with all study participants and offer ART to the control group (people who had been randomized to not start ART) before the study ended. As a result of the study there was increased consensus that treatment as prevention should be included as a public health strategy in lowering HIV infection. The trial was organized by the HIV Prevention Trials Network (HPTN) and its chief architect was Myron S. Cohen. Results As reported by a 2011 publication in the ''New England Journal of Medicine'', in the trial there were 1763 couples, where only one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Machine
A quantum machine is a human-made device whose collective motion follows the laws of quantum mechanics. The idea that macroscopic objects may follow the laws of quantum mechanics dates back to the advent of quantum mechanics in the early 20th century. However, as highlighted by the Schrödinger's cat thought experiment, quantum effects are not readily observable in large-scale objects. Consequently, quantum states of motion have only been observed in special circumstances at extremely low temperatures. The fragility of quantum effects in macroscopic objects may arise from rapid quantum decoherence. Researchers created the first quantum machine in 2009, and the achievement was named the "Breakthrough of the Year" by ''Science (journal), Science'' in 2010. History The first quantum machine was created on August 4, 2009, by Aaron D. O'Connell while pursuing his Ph.D. under the direction of Andrew N. Cleland and John M. Martinis at the University of California, Santa Barbara. O'C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ardipithecus Ramidus
''Ardipithecus ramidus'' is a species of australopithecine from the Afar region of Early Pliocene Ethiopia 4.4 million years ago (mya). The species ''A. ramidus'' is the type species for the genus ''Ardipithecus''. There is an older species in this same genus, ''Ardipithecus kadabba''. ''A. ramidus'', unlike modern hominids, has adaptations for both walking on two legs (bipedality) and life in the trees (arboreality). However, it would not have been as efficient at bipedality as humans, nor at arboreality as non-human great apes. Its discovery, along with Miocene apes, has reworked academic understanding of the chimpanzee–human last common ancestor from appearing much like modern-day chimpanzees, orangutans and gorillas to being a creature without a modern analogue. The facial anatomy (specifically the reduced sexual dimorphism of the canines) suggests that ''A. ramidus'' males were less aggressive than those of modern chimps, which is correlated to increased parental care an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Reprogramming
Induced pluripotent stem cells (also known as iPS cells or iPSCs) are a type of pluripotent stem cell that can be generated directly from a somatic cell. The iPSC technology was pioneered by Shinya Yamanaka and Kazutoshi Takahashi in Kyoto, Japan, who together showed in 2006 that the introduction of four specific genes (named Myc, Oct3/4, Sox2 and Klf4), collectively known as Yamanaka factors, encoding transcription factors could convert somatic cells into pluripotent stem cells. Shinya Yamanaka was awarded the 2012 Nobel Prize along with Sir John Gurdon "for the discovery that mature cells can be reprogrammed to become pluripotent." Pluripotent stem cells hold promise in the field of regenerative medicine. Because they can propagate indefinitely, as well as give rise to every other cell type in the body (such as neurons, heart, pancreatic, and liver cells), they represent a single source of cells that could be used to replace those lost to damage or disease. The most wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Genetic Variation
Human genetic variation is the genetic differences in and among populations. There may be multiple variants of any given gene in the human population (alleles), a situation called polymorphism. No two humans are genetically identical. Even monozygotic twins (who develop from one zygote) have infrequent genetic differences due to mutations occurring during development and gene copy-number variation. Differences between individuals, even closely related individuals, are the key to techniques such as genetic fingerprinting. The human genome has a total length of approximately 3.2 billion base pairs (bp) in 46 chromosomes of DNA as well as slightly under 17,000 bp DNA in cellular mitochondria. In 2015, the typical difference between an individual's genome and the reference genome was estimated at 20 million base pairs (or 0.6% of the total). As of 2017, there were a total of 324 million known variants from sequenced human genomes. Comparatively speaking, humans are a genetica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poincaré Conjecture
In the mathematical field of geometric topology, the Poincaré conjecture (, , ) is a theorem about the characterization of the 3-sphere, which is the hypersphere that bounds the unit ball in four-dimensional space. Originally conjectured by Henri Poincaré in 1904, the theorem concerns spaces that locally look like ordinary three-dimensional space but which are finite in extent. Poincaré hypothesized that if such a space has the additional property that each loop in the space can be continuously tightened to a point, then it is necessarily a three-dimensional sphere. Attempts to resolve the conjecture drove much progress in the field of geometric topology during the 20th century. The eventual proof built upon Richard S. Hamilton's program of using the Ricci flow to solve the problem. By developing a number of new techniques and results in the theory of Ricci flow, Grigori Perelman was able to modify and complete Hamilton's program. In papers posted to the arXiv reposi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution
Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation. The scientific theory of evolution by natural selection was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace, in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book ''On the Origin of Species''. Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) phenotypic variatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirit (rover)
''Spirit'', also known as MER-A (Mars Exploration Rover – A) or MER-2, is a Mars rover, Mars robotic rover, active from 2004 to 2010. ''Spirit'' was operational on Mars for Timekeeping on Mars#Sols, sols or 3.3 Martian years ( days; '). It was one of two rover (space exploration), rovers of NASA's Mars Exploration Rover Mission managed by the Jet Propulsion Laboratory (JPL). Spirit landed successfully within the impact crater Gusev (Martian crater), Gusev on Mars at 04:35 Ground UTC on January 4, 2004, three weeks before its twin, ''Opportunity (rover), Opportunity'' (MER-B), which landed on the other side of the planet. Its name was chosen through a Sofi Collis, NASA-sponsored student essay competition. The rover got stuck in a "sand trap" in late 2009 at an angle that hampered recharging of its batteries; its last communication with Earth was on March 22, 2010. The rover completed its planned 90-Martian day, sol mission (slightly less than 92.5 Earth days). Aided by cleani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
