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The article reports on the two papers which were linked to an extortion attempt and originated from the laboratory of Peter Schultz, a prominent chemist at the Scripps Research Institute in La Jolla, San Diego, California. The papers claimed to describe the successful incorporation of amino acids linked to sugars at specific positions in proteins made by the bacterium Escherichia coli. Related issues are further discussed.

The article discusses the capacity animals and plant to shift with the changing climates and habitats. Plants and animals tend to shift with the changes at a phenomenal speed, according to global ecologist Christopher Field of the Carnegie Institution for Science in Stanford, California. While Carnegie postdoc Scott Loarie said that species who are used to the tropics tend to prefer continuous forests, than forest fragments.

The article discusses the introduction of near-field imaging to electron microscopy to develop real-time movies of nanometre-sized structures by Ahmed Zewail and his colleagues at the California Institute of Technology in Pasadena. The dubbed photon-induced near-field electron microscopy (PINEM) technique has the ability to alter the way scientists examine the nanoworld. Zewail mentions how his team work hard to discover fields of electrons within the nanostructures.

The article reports on the move of geologist Taylor Perron and his colleagues Jim Kirchner and Bill Dietrich at University of California, Berkeley, to examine how erosional processes create uniform patterns of landscapes. They compare a computational model with precise measurements of various landscapes. Moreover, it reveals that having developed a computational model that accurately predicts the natural patterns in landscapes, geologists can learn how factors have shaped Earth's topography.

The article reports on the breakthrough in stem cell research in Japan in 2006 and the efforts of various scientists worldwide in testing the cells in 2009. According to the Japanese research, induced pluripotent stem (iPS) cells were produced when mouse skin cells return to an embryonic cell through manipulation. It cites that scientist Juan Carlos Izpisúa Belmonte and his colleagues in California, has successfully generated iPS cells from skin cells of a patient with Fanconi anaemia.

The article profiles Phil Baran, a researcher and author for the journal "Nature Chemical Biology." It states the Baran is also an organic chemist at the Scripps Research Institute in La Jolla, California. According to the article, since he was called up to work on the review of the terpenes, he agreed to do the task and developed his knowledge in terpene field. Further information on the researches of Baran related to chemical synthesis is presented.

The article elaborates on the study conducted by Charles Cobb, a neurosurgeon at the California Pacific Medical Center, in San Francisco, California. Aside from practicing his profession, he is also a virus hunter, Since 1998, he studied on whether viruses have an association with brain tumours. He and his co-authors discovered that the human cytomegalovirus (HCMV) needs a particular cellular receptor, normally involved in growth-factor signaling, to infect a type of cancer cell in the brain. He found out that this type of virus causes defects at birth and fatal diseases in immunocompromised people, especially patients with AIDS. People who are infected with the virus is associated with the occurrence of glioma, an extremely aggressive form of brain cancer that is difficult to treat.

The article discusses the success of Erica Ollmann Saphire, an immunologist at the Scripps Research Institute in La Jolla, California, and her team in winning the race on providing a picture of how the deadly Ebola virus evades the immune system and enter cells. The move was risky and the work was long and difficult. It took them over four years to express 130 versions of the Ebola virus glycoprotein, grow and test crystal diffractions. The team found out that the virus can lie in wait for years. Saphire and her colleagues managed to solve the structure of an infection-blocking antibody bound to a viral protein, revealing a possible defence against the virus.

The article focuses on the effort of Douglas Hofmann to produce a new class of resistive bulk metallic glasses. In 2003, he studied the materials engineering program together with his college teacher William Johnson at the California Institute of Technology (Caltech) in California. He further knew the concept of ductility to the glasses. He decided to apply the induction coil, an instrument which conducts heat over a lower range of temperature. Based on the subsequent analysis, he learned that two phases are formed when the glass composites are heated in the temperature range above the melting point of glass and below the dendrite's temperature.

The article provides information on the research of neuroscientist Gilles Laurent of the California Institute of Technology in Pasadena, California, using locust as a model in experimenting the neural mechanisms of insects use to learn odors. He chose the locust as a model of his study in which he first began studying insect olfaction because it was a good way of tracing circuit function and neural computation in the brain. Meanwhile, the article also discusses the detailed experimental design and the results of the study.

The article focuses on Lawrence Steinman, a neurologist from Stanford University in Palo Alto, California who studied the role of protein αB-crystallin (CRYAB), an eye lens protein in the neurological disease multiple sclerosis. The work of Steinman distinguished CRYAB as a central agent in controlling inflammation and programmed cell death in the brain. Steinman's team has also shown that CRYAB likewise tones down many inflammatory pathways and helps in preventing programmed cell death.

The article discusses the study on the development of ciliated cells in the skin of the African clawed frog Xenopus laevis by Chris Kintner, a molecular neurobiologists, and his team in California. It is stated that the group observed that Xenopus embryos tended to float at the bottom of the culture media because of the cilia on the skin cells. The group realized that when cilia first form on cells in Xenopus skin, they tend to point towards the tail.

The article analyzes the missing link between T lymphocytes and psoriasis. The observations of Immunologist Yan Zheng and his colleagues at the company Genentech in San Francisco, California are discussed in detail. An overview of the cause for the white cell infiltration into the skin and the role of IL-22 in causing the disease of psoriasis, through experimentation on mice, is presented. The article also presents the observations of Wenjun Ouyang on TH 17 and T22 to find the missing link.

The article describes how Jay Keasling, a synthetic chemist at the University of California, Berkeley, and his team have engineered yeast cells to produce an important precursor for a drug to treat malaria. Keasling collaborated with Amyris Biotechnologies and non-profit drug company Institute for OneWorld Health to try to complete the synthesis of artemisinin. The research was funded by the Bill & Melinda Gates Foundation.

The article focuses on the career of Cheng-Ming Chuong, a developmental biologist at the University of Southern California in Los Angeles. Chuong has interest on how feathers are generated in adult birds. He decided to try to track down the location of stem cells in feathers. Chuong and his team discovered that in flight feathers, the ring of stem cells tilts towards the side where the quill arises. He plans to continue his characterization of feather stem cells.

Reports that Agouron Pharmaceuticals, La Jolla, California, has been found guilty of stealing research. Work stolen from Huguette Pelletier when she worked at the University of California at San Diego; Pelletier's work published by Agouron in `Cell'; Decision of a state court jury against Agouron.

The article discusses the contribution of Bob Klein as chairman of the California Institute for Regenerative Medicine (CIRM). It mentions the legacy that he left after his resignation on December 17, 2010 including six new facilities, 700 scientific papers and 1.15 billion U.S. dollars in grants. It also notes his advocacy on the promotion of human embryonic stem-cell research in the U.S. to seek an effective treatment for diabetes.

Focuses on David Eisenberg's laboratory at the University of California in Los Angeles. Scientific work involving the interaction of proteins; Papers written by Eisenberg from the laboratory.

The article discusses the research being conducted by molecular biologists Robert Place and Long-Cheng Li in San Francisco, California on microRNA (miRNA), a type of genetic regulator that dampens gene expression. According to the author, both scientists believe that their research has found miRNAs that could boost gene expression in cells. The author says that their work could generate a heated response in the field of RNA interference, which is the study of how short pieces of RNA regulate the expression of genes.

Presents an interview with Shri Kulkarni, professor of astronomy at the California Institute of Technology in California. Views on the proponent of learning different observational techniques; Intensity of the gamma ray bursts on the merger of neutron; Determination of approach in publication record and overall output.

The author reflects on the release of climate change research results to the mass media before undergoing peer review. The author notes research from the Berkeley Earth Surface Temperature (BEST) team at the University of California, Berkeley which became interest to the mass media but was criticized by the scientific community who viewed the media coverage as publicity before peer review. The author adds that communication of science occurred before the scientific process was incomplete.

The article profiles Matthew Lewin, an emergency-care doctor with a specialty in widlerness medicine. In addition to operating as a medic in places such as Chile, Peru and Mongolia, he has released more than 40 papers on work that ranges from defensive behaviour of moth larvae and exotic parasites to how to open the throat of a person during improvised surgery. He has trained U.S. special-forces medics, national-park responders and medical students at the University of California in San Francisco, California, in methods to treat patients in the field.

The article reports on the claims of PrimeGen, a biotechnological company based in Irvine, California, that it has used carbon nanotubes to reprogram adult human cells to an embryonic-like state, a breakthrough that removes the elevated risk of cancer that blights other techniques. PrimeGene researchers used the nanotube delivery system to introduce genes into human testicular and retinal cells, and PrimeGene has reported that they were quickly taken up by an impressive 80% of the cells. It is reported that PrimeGene announced an alliance with Unidym, based in Menlo Park, California, which makes the nanotubes.

The article reports on the discovery of the clumped isotope thermometry, a valuable tool for paleoenvironmental studies by a group of researchers at the California Institute of Technology (Caltech) in Pasadena, California. The new tool was discovered by measuring the abundance of molecules which contain oxygen-isotope and the uncommon carbon-isotope. According to published papers, the results of early test of this clumped thermometer on corals and fish earbones were promising which provides a new record of ocean temperature during Paleozoic era.

The article focuses on the academic analysis which shows the weak foundation of electronic voting systems in California. The analysis was made possible by the scientists of Berkeley and Davis campuses of the University of California in Berkeley. The analysis indicates that the three systems purchased by the state from Sequoia Voting Systems Inc., Hart InterCivic Inc. and Diebold Inc. failed to meet the needed security requirements for the voters. Secretary of state Debra Bowen said that the result would allow voters to use paper ballots for the February 2008 elections and promised the public to reattest the machines once they comply with the basic requirements for the voting system. Meanwhile, reactions of other public officials on the analysis result are offered.

Comments on the letter by author Richard Buttery published in the 424 volume of the journal "Nature" about the Joint European Torus (JET) as of October 16, 2003. Statements given by the author on the situation that might occur if there were no substantial increase in the fusion budget in the Seventh Euratom Framework Programme; Criticism made by the author about the misinterpretation of his statements about JET in the letter; Relationship between JET and International Thermonuclear Experimental Reactor in La Jolla, California.

Discusses a legal case about whether a plasmid discovered at and patented by the University of California at San Francisco contributed to the early success of Genentech, Inc. Evidence of the conflict in the pages of `Nature'; How the case shows the commercial pressures on the biotechnology industry.

The article provides information on the recent developments across the world related to science and technology. Months of confusion ended last week when the U.S. Department of the Treasury issued licenses that permit the U.S. publishers to accept and print scholarly papers with authors from Cuba, Iran and Sudan. A convoy carrying US$4.6 million worth of laboratory equipment and $1 million worth of academic books is bound for higher-education institutions in Iraq. Impulse Devices, a company in Grass Valley, California is launching an experimental power reactor based on "bubble fusion," despite reservations within the scientific community over whether the effect exists. Zsuzsanna Jakab, secretary of state at Hungary's ministry of health, was last week nominated as the inaugural director of the European Center for Disease Prevention and Control.

Groundwater use in California's San Joaquin Valley exceeds replenishment of the aquifer, leading to substantial diminution of this resource and rapid subsidence of the valley floor. The volume of groundwater lost over the past century and a half also represents a substantial reduction in mass and a large-scale unburdening of the lithosphere, with significant but unexplored potential impacts on crustal deformation and seismicity. Here we use vertical global positioning system measurements to show that a broad zone of rock uplift of up to 1-3 mm per year surrounds the southern San Joaquin Valley. The observed uplift matches well with predicted flexure from a simple elastic model of current rates of water-storage loss, most of which is caused by groundwater depletion. The height of the adjacent central Coast Ranges and the Sierra Nevada is strongly seasonal and peaks during the dry late summer and autumn, out of phase with uplift of the valley floor during wetter months. Our results suggest that long-term and late-summer flexural uplift of the Coast Ranges reduce the effective normal stress resolved on the San Andreas Fault. This process brings the fault closer to failure, thereby providing a viable mechanism for observed seasonality in microseismicity at Parkfield and potentially affecting long-term seismicity rates for fault systems adjacent to the valley. We also infer that the observed contemporary uplift of the southern Sierra Nevada previously attributed to tectonic or mantle-derived forces is partly a consequence of human-caused groundwater depletion. [ABSTRACT FROM AUTHOR]

The article focuses on MaterniT21, a Down's syndrome test and non-invasive fetal gene screening, with ethical problems launched by Sequenom Inc. of San Diego, California to the market across the U.S. on October 17, 2011. It states that the Sequenom's Inc. test sequences 36-base-pair of DNA which to determine sections form chromosome 21. Mathias Ehriad, senior director for research and development diagnostics adds that the company focuses on developing tests on the prenatal screening programmes.

The article presents information on the study conducted by scientists Brice Kuhl, Anthony Wagner and their team at Stanford University in California to determine the activity of hippocampus in brain.

The article reports on a study led by Morris Cohen of Stanford University in California, which developed a map that can pinpoint the location of terrestrial lightning bolts, or gamma ray bursts, and their associated flashes.

The article presents a study on the generation of cells from umbilical cord blood by Ulrich Martin of Hannover Medical School in Germany and Juan Carlos Izpisua Belmonte of Salk Institute for Biological Studies in La Jolla, California. It cites that Martin created the cells with the use of four genes while Belmonte uses only two genes to generate induced pluripotent stem (iPS) cells. The researchers have derived iPS cell lines which could be useful in medicine.

An interview with Benoit Bruneau, a researcher at the Gladstone Institute of Cardiovascular Disease in San Francisco, California, is presented. He asserts that he is interested on studying different hearts' organisms because by comparing them, he can often gain insight into similar process. He states that since he and his colleagues have understood how important Tbx5 protein to ventricular separation, they can already focus on how it helps the heart develop a septum.

The article reports on the research conducted by Kirsten Howley of the University of California regarding the M32, the spiral galaxy near the Milky Way and NGC205, a nearby dwarf elliptical galaxy, in California. Researchers used a genetic algorithm to determine that NGC205 is swinging around M31 and found NGC 205 was zipping past M31 at hundreds of kilometres per second, close to its escape velocity. NCG 205's motion is perpendicular to, and therefore independent of, a streamer of stars that is associated with it.

An interview with Gary Siuzdak, director of the mass spectrometry center at the Scripps Research Institute in La Jolla, California, is presented. When asked what motivates them to make a research concerning mass spectrometry, he refers to the improvement of its technique for analyzing biomolecules. He discusses types of sample they test first and applications that they find most interesting during the research.

The article provides information on the biological process of converting sound waves into electrical impulses by hair cells in the cochlea. As stated by Ulrich Müller and colleagues at the Scripps Research Institute in La Jolla, San Diego, California, hair cells will allow individuals to hear sound through sound waves conversion. It states that the end of the hair cell is a bundle of stereocilla which are connected to each other through structures. It likewise claims that when the structures are deflected by sound pressure they will exert a force which would open the channels resulting to sound creation.

The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from lower-crustal and upper-mantle depths is most pronounced about thirty kilometres southeast of Parkfield and is thought to be associated with high pore-fluid pressures at depth. Here we present geophysical evidence of fluids migrating into the creeping section of the San Andreas fault that seem to originate in the region of the uppermost mantle that also stimulates tremor, and evidence that along-strike variations in tremor activity and amplitude are related to strength variations in the lower crust and upper mantle. Interconnected fluids can explain a deep zone of anomalously low electrical resistivity that has been imaged by magnetotelluric data southwest of the Parkfield-Cholame segment. Near Cholame, where fluids seem to be trapped below a high-resistivity cap, tremor concentrates adjacent to the inferred fluids within a mechanically strong zone of high resistivity. By contrast, subvertical zones of low resistivity breach the entire crust near the drill hole of the San Andreas Fault Observatory at Depth, northwest of Parkfield, and imply pathways for deep fluids into the eastern fault block, coincident with a mechanically weak crust and the lower tremor amplitudes in the lower crust. Fluid influx to the fault system is consistent with hypotheses of fault-weakening high fluid pressures in the brittle crust. [ABSTRACT FROM AUTHOR]

The San Andreas fault accommodates 28-34 mm yr−1 of right lateral motion of the Pacific crustal plate northwestward past the North American plate. In California, the fault is composed of two distinct locked segments that have produced great earthquakes in historical times, separated by a 150-km-long creeping zone. The San Andreas Fault Observatory at Depth (SAFOD) is a scientific borehole located northwest of Parkfield, California, near the southern end of the creeping zone. Core was recovered from across the actively deforming San Andreas fault at a vertical depth of 2.7 km (ref. 1). Here we report laboratory strength measurements of these fault core materials at in situ conditions, demonstrating that at this locality and this depth the San Andreas fault is profoundly weak (coefficient of friction, 0.15) owing to the presence of the smectite clay mineral saponite, which is one of the weakest phyllosilicates known. This Mg-rich clay is the low-temperature product of metasomatic reactions between the quartzofeldspathic wall rocks and serpentinite blocks in the fault. These findings provide strong evidence that deformation of the mechanically unusual creeping portions of the San Andreas fault system is controlled by the presence of weak minerals rather than by high fluid pressure or other proposed mechanisms. The combination of these measurements of fault core strength with borehole observations yields a self-consistent picture of the stress state of the San Andreas fault at the SAFOD site, in which the fault is intrinsically weak in an otherwise strong crust. [ABSTRACT FROM AUTHOR]

The article highlights the Synthetic Biology 2.0 conference held at the University of California in Berkeley, California. This conference resulted to an open letter that denounced the ambitions of synthetic biology and objected to the idea that its practitioners might institute structure of self-governance to mitigate some of its inherent risks.

Communities have been shaped in numerous ways by past climatic change; this process continues today. At the end of the Pleistocene epoch about 11,700 years ago, North American communities were substantially altered by the interplay of two events. The climate shifted from the cold, arid Last Glacial Maximum to the warm, mesic Holocene interglacial, causing many mammal species to shift their geographic distributions substantially. Populations were further stressed as humans arrived on the continent. The resulting megafaunal extinction event, in which 70 of the roughly 220 largest mammals in North America (32%) became extinct, has received much attention. However, responses of small mammals to events at the end of the Pleistocene have been much less studied, despite the sensitivity of these animals to current and future environmental change. Here we examine community changes in small mammals in northern California during the last ‘natural’ global warming event at the Pleistocene–Holocene transition and show that even though no small mammals in the local community became extinct, species losses and gains, combined with changes in abundance, caused declines in both the evenness and richness of communities. Modern mammalian communities are thus depauperate not only as a result of megafaunal extinctions at the end of the Pleistocene but also because of diversity loss among small mammals. Our results suggest that across future landscapes there will be some unanticipated effects of global change on diversity: restructuring of small mammal communities, significant loss of richness, and perhaps the rising dominance of native ‘weedy’ species. [ABSTRACT FROM AUTHOR]

The San Andreas fault is one of the most extensively studied faults in the world, yet its physical character and deformation mode beneath the relatively shallow earthquake-generating portion remain largely unconstrained. Tectonic ‘non-volcanic’ tremor, a recently discovered seismic signal probably generated by shear slip on the deep extension of some major faults, can provide new insight into the deep fate of such faults, including that of the San Andreas fault near Parkfield, California. Here I examine continuous seismic data from mid-2001 to 2008, identifying tremor and decomposing the signal into different families of activity based on the shape and timing of the waveforms at multiple stations. This approach allows differentiation between activities from nearby patches of the deep fault and begins to unveil rich and complex patterns of tremor occurrence. I find that tremor exhibits nearly continuous migration, with the most extensive episodes propagating more than 20 kilometres along fault strike at rates of 15–80 kilometres per hour. This suggests that the San Andreas fault remains a localized through-going structure, at least to the base of the crust, in this area. Tremor rates and recurrence behaviour changed markedly in the wake of the 2004 magnitude-6.0 Parkfield earthquake, but these changes were far from uniform within the tremor zone, probably reflecting heterogeneous fault properties and static and dynamic stresses decaying away from the rupture. The systematic recurrence of tremor demonstrated here suggests the potential to monitor detailed time-varying deformation on this portion of the deep San Andreas fault, deformation which unsteadily loads the shallower zone that last ruptured in the 1857 magnitude-7.9 Fort Tejon earthquake. [ABSTRACT FROM AUTHOR]

Focuses on the efforts of the University of California in collaboration with the African American Male Achievers Network to teach middle- and high-school students about the work of scientists in Los Angeles, California. Aim of the program to increase the number of students to pursue their career in natural and physical sciences; Invitation for high school students to work with scientists in laboratories; Importance of the bond between students and scientists with the program.

Since its initial discovery nearly a decade ago, non-volcanic tremor has provided information about a region of the Earth that was previously thought incapable of generating seismic radiation. A thorough explanation of the geologic process responsible for tremor generation has, however, yet to be determined. Owing to their location at the plate interface, temporal correlation with geodetically measured slow-slip events and dominant shear wave energy, tremor observations in southwest Japan have been interpreted as a superposition of many low-frequency earthquakes that represent slip on a fault surface. Fluids may also be fundamental to the failure process in subduction zone environments, as teleseismic and tidal modulation of tremor in Cascadia and Japan and high Poisson ratios in both source regions are indicative of pressurized pore fluids. Here we identify a robust correlation between extremely small, tidally induced shear stress parallel to the San Andreas fault and non-volcanic tremor activity near Parkfield, California. We suggest that this tremor represents shear failure on a critically stressed fault in the presence of near-lithostatic pore pressure. There are a number of similarities between tremor in subduction zone environments, such as Cascadia and Japan, and tremor on the deep San Andreas transform, suggesting that the results presented here may also be applicable in other tectonic settings. [ABSTRACT FROM AUTHOR]

Measuring stress changes within seismically active fault zones has been a long-sought goal of seismology. One approach is to exploit the stress dependence of seismic wave velocity, and we have investigated this in an active source cross-well experiment at the San Andreas Fault Observatory at Depth (SAFOD) drill site. Here we show that stress changes are indeed measurable using this technique. Over a two-month period, we observed an excellent anti-correlation between changes in the time required for a shear wave to travel through the rock along a fixed pathway (a few microseconds) and variations in barometric pressure. We also observed two large excursions in the travel-time data that are coincident with two earthquakes that are among those predicted to produce the largest coseismic stress changes at SAFOD. The two excursions started approximately 10 and 2 hours before the events, respectively, suggesting that they may be related to pre-rupture stress induced changes in crack properties, as observed in early laboratory studies. [ABSTRACT FROM AUTHOR]

It is now clear that fished populations can fluctuate more than unharvested stocks. However, it is not clear why. Here we distinguish among three major competing mechanisms for this phenomenon, by using the 50-year California Cooperative Oceanic Fisheries Investigations (CalCOFI) larval fish record. First, variable fishing pressure directly increases variability in exploited populations. Second, commercial fishing can decrease the average body size and age of a stock, causing the truncated population to track environmental fluctuations directly. Third, age-truncated or juvenescent populations have increasingly unstable population dynamics because of changing demographic parameters such as intrinsic growth rates. We find no evidence for the first hypothesis, limited evidence for the second and strong evidence for the third. Therefore, in California Current fisheries, increased temporal variability in the population does not arise from variable exploitation, nor does it reflect direct environmental tracking. More fundamentally, it arises from increased instability in dynamics. This finding has implications for resource management as an empirical example of how selective harvesting can alter the basic dynamics of exploited populations, and lead to unstable booms and busts that can precede systematic declines in stock levels. [ABSTRACT FROM AUTHOR]

Discusses the issues associated with the auction of an historic archive of molecular biology documents in San Diego, California. Reaction of the researchers to the separate sale of the papers; Value of the documents.

Crown-group crustaceans (Eucrustacea) are common in the fossil record of the past 500 million years back to the early Ordovician period, and very rare representatives are also known from the late Middle and Late Cambrian periods. Finds in Lower Cambrian rocks of the Phosphatocopina, the fossil sister group to eucrustaceans, imply that members of the eucrustacean stem lineage co-occurred, but it remained unclear whether crown-group members were also present at that time. ‘Orsten’-type fossils are typically tiny embryos and cuticle-bearing animals, of which the cuticle is phosphatized and the material is three-dimensional and complete with soft parts. Such fossils are found predominantly in the Cambrian and Ordovician and provide detailed morphological and phylogenetic information on the early evolution of metazoans. Here we report an Orsten-type Konservat-Lagerstätte from the Lower Cambrian of China that contains at least three new arthropod species, of which we describe the most abundant form on the basis of exceptionally well preserved material of several growth stages. The limb morphology and other details of this new species are markedly similar to those of living cephalocarids, branchiopods and copepods and it is assigned to the Eucrustacea, thus representing the first undoubted crown-group crustacean from the early Cambrian. Its stratigraphical position provides substantial support to the proposition that the main cladogenic event that gave rise to the Arthropoda was before the Cambrian. Small leaf-shaped structures on the outer limb base of the new species provide evidence on the long-debated issue of the origin of epipodites: they occur in a set of three, derive from setae and are a ground-pattern feature of Eucrustacea. [ABSTRACT FROM AUTHOR]

The San Andreas fault in California is a mature continental transform fault that accommodates a significant fraction of motion between the North American and Pacific plates. The two most recent great earthquakes on this fault ruptured its northern and central sections in 1906 and 1857, respectively. The southern section of the fault, however, has not produced a great earthquake in historic times (for at least 250 years). Assuming the average slip rate of a few centimetres per year, typical of the rest of the San Andreas fault, the minimum amount of slip deficit accrued on the southern section is of the order of 7–10 metres, comparable to the maximum co-seismic offset ever documented on the fault. Here I present high-resolution measurements of interseismic deformation across the southern San Andreas fault system using a well-populated catalogue of space-borne synthetic aperture radar data. The data reveal a nearly equal partitioning of deformation between the southern San Andreas and San Jacinto faults, with a pronounced asymmetry in strain accumulation with respect to the geologically mapped fault traces. The observed strain rates confirm that the southern section of the San Andreas fault may be approaching the end of the interseismic phase of the earthquake cycle. [ABSTRACT FROM AUTHOR]

Fracture energy is a form of latent heat required to create an earthquake rupture surface and is related to parameters governing rupture propagation and processes of slip weakening. Fracture energy has been estimated from seismological and experimental rock deformation data, yet its magnitude, mechanisms of rupture surface formation and processes leading to slip weakening are not well defined. Here we quantify structural observations of the Punchbowl fault, a large-displacement exhumed fault in the San Andreas fault system, and show that the energy required to create the fracture surface area in the fault is about 300 times greater than seismological estimates would predict for a single large earthquake. If fracture energy is attributed entirely to the production of fracture surfaces, then all of the fracture surface area in the Punchbowl fault could have been produced by earthquake displacements totalling <1 km. But this would only account for a small fraction of the total energy budget, and therefore additional processes probably contributed to slip weakening during earthquake rupture. [ABSTRACT FROM AUTHOR]