bluuebunny/crossref_metadata_2025 huggingface dataset:
Airflow-Housing-Induced Resonances of Rotating Optical Disks
Authors: Mestrom R. M. C. , Fey R. H. B. , Nijmeijer H. , Wortelboer P. M. R. , Aerts W.
Published: November 2007

Numerous excitation sources for disk vibrations are present in optical drives. For increasing rotation speeds, airflow-housing-induced vibrations have become more and more important. Currently, drives are designed in which rotation speeds are so high that critical speed resonances may show up. The presence of these resonances depends on the layout of the inner housing geometry of the drive. The influence of the drive inner housing geometry is investigated systematically by means of a numerical-experimental approach. An analytical model is derived, containing disk dynamics and the geometry-induced pressure distribution acting as the excitation mechanism on the disk. The Reynolds’ lubrication equation is used as a first approach for the modeling of the pressure distribution. The model is numerically implemented using an approach based on a combination of finite element and finite difference techniques. An idealized, drive-like environment serves as the experimental setup. This setup resembles the situation in the numerical model, in order to be able to verify the numerical model. Wedge-like airflow disturbances are used in order to obtain insight into the influence of drive inner geometry on the critical speed resonances of optical disks. A disk tilt measurement method is designed that yields a global view of the disk deformation. By means of two newly proposed types of plots, numerical and experimental results can be compared in a straightforward way. A qualitative match between the numerical and experimental results is obtained. The numerical and experimental methods presented provide insight into airflow-housing-induced vibrations in optical drives. Additionally, reduction of some critical speed resonances is found to be possible for certain drive inner geometry configurations.
Semi-Analytic Hybrid Method to Predict Springback in the 2D Draw Bend Test
Authors: Lee Myoung-Gyu , Kim Daeyong , Wagoner R. H. , Chung Kwansoo
Published: November 2007

A simplified numerical procedure to predict springback in a 2D draw bend test was developed based on the hybrid method which superposes bending effects onto membrane solutions. In particular, the procedure was applied for springback analysis of a specially designed draw bend test with directly controllable restraining forces. As a semi-analytical method, the new approach was especially useful to analyze the effects of various process and material parameters on springback. The model can accommodate general anisotropic yield functions along with nonlinear isotropic-kinematic hardening under the plane strain condition. For sensitivity analysis, process effects such as the amount of bending curvature, normalized back force and friction, as well as material property effects such as hardening behavior including the Bauschinger effect and yield surface shapes were studied. Also, for validation purposes, the new procedure was applied for the springback analysis of the dual-phase high strength steel and results were compared with experiments.
On the Stoney Formula for a Thin Film/Substrate System With Nonuniform Substrate Thickness
Authors: Feng X. , Huang Y. , Rosakis A. J.
Published: November 2007

Current methodologies used for the inference of thin film stress through system curvature measurements are strictly restricted to stress and curvature states which are assumed to remain uniform over the entire film/substrate system. Recently Huang, Rosakis, and co-workers [Acta Mech. Sinica, 21, pp. 362–370 (2005); J. Mech. Phys. Solids, 53, 2483–2500 (2005); Thin Solid Films, 515, pp. 2220–2229 (2006); J. Appl. Mech., in press; J. Mech. Mater. Struct., in press] established methods for the film/substrate system subject to nonuniform misfit strain and temperature changes. The film stresses were found to depend nonlocally on system curvatures (i.e., depend on the full-field curvatures). These methods, however, all assume uniform substrate thickness, which is sometimes violated in the thin film/substrate system. Using the perturbation analysis, we extend the methods to nonuniform substrate thickness for the thin film/substrate system subject to nonuniform misfit strain.
Algorithms of Boundless Beauty
Authors: Buck Gregory
Published: November 2007

Arabesques
Decorative Art in Morocco. Jean-Marc Castéra. ACR [Art, Création, Réalisation], Paris, 1999. 480 pp. 680 FF, EUR 103.67. ISBN 2-86770-124-4.

This coffee-table book offers a stunningly presented sample of Islamic tiling and architecture from Morocco along with mathematical analyses of the artists' myriad approaches to the geometry.
Fast Backprojections from the Motion to the Primary Visual Area Necessary for Visual Awareness
Authors: Pascual-Leone Alvaro , Walsh Vincent
Published: November 2007

Much is known about the pathways from photoreceptors to higher visual areas in the brain. However, how we become aware of what we see or of having seen at all is a problem that has eluded neuroscience. Recordings from macaque V1 during deactivation of MT+/V5 and psychophysical studies of perceptual integration suggest that feedback from secondary visual areas to V1 is necessary for visual awareness. We used transcranial magnetic stimulation to probe the timing and function of feedback from human area MT+/V5 to V1 and found its action to be early and critical for awareness of visual motion.
Enlarging the Amino Acid Set of
Escherichia coli
by Infiltration of the Valine Coding Pathway
Authors: Döring Volker , Mootz Henning D. , Nangle Leslie A. , Hendrickson Tamara L. , de Crécy-Lagard Valérie , Schimmel Paul , Marlière Philippe
Published: November 2007

Aminoacyl transfer RNA (tRNA) synthetases establish the rules of the genetic code by catalyzing the aminoacylation of tRNAs. For some synthetases, accuracy depends critically on an editing function at a site distinct from the aminoacylation site. Mutants of
Escherichia coli
that incorrectly charge tRNA
Val
with cysteine were selected after random mutagenesis of the whole chromosome. All mutations obtained were located in the editing site of valyl-tRNA synthetase. More than 20% of the valine in cellular proteins from such an editing mutant organism could be replaced with the noncanonical aminobutyrate, sterically similar to cysteine. Thus, the editing function may have played a central role in restricting the genetic code to 20 amino acids. Disabling this editing function offers a powerful approach for diversifying the chemical composition of proteins and for emulating evolutionary stages of ambiguous translation.
A Quantum Adiabatic Evolution Algorithm Applied to Random Instances of an NP-Complete Problem
Authors: Farhi Edward , Goldstone Jeffrey , Gutmann Sam , Lapan Joshua , Lundgren Andrew , Preda Daniel
Published: November 2007

A quantum system will stay near its instantaneous ground state if the Hamiltonian that governs its evolution varies slowly enough. This quantum adiabatic behavior is the basis of a new class of algorithms for quantum computing. We tested one such algorithm by applying it to randomly generated hard instances of an NP-complete problem. For the small examples that we could simulate, the quantum adiabatic algorithm worked well, providing evidence that quantum computers (if large ones can be built) may be able to outperform ordinary computers on hard sets of instances of NP-complete problems.
Matriarchs As Repositories of Social Knowledge in African Elephants
Authors: McComb Karen , Moss Cynthia , Durant Sarah M. , Baker Lucy , Sayialel Soila
Published: November 2007

Despite widespread interest in the evolution of social intelligence, little is known about how wild animals acquire and store information about social companions or whether individuals possessing enhanced social knowledge derive biological fitness benefits. Using playback experiments on African elephants (
Loxodonta africana
), we demonstrated that the possession of enhanced discriminatory abilities by the oldest individual in a group can influence the social knowledge of the group as a whole. These superior abilities for social discrimination may result in higher per capita reproductive success for female groups led by older individuals. Our findings imply that the removal of older, more experienced individuals, which are often targets for hunters because of their large size, could have serious consequences for endangered populations of advanced social mammals such as elephants and whales.
Cooperation and Competition in the Evolution of ATP-Producing Pathways
Authors: Pfeiffer Thomas , Schuster Stefan , Bonhoeffer Sebastian
Published: November 2007

Heterotrophic organisms generally face a trade-off between rate and yield of adenosine triphosphate (ATP) production. This trade-off may result in an evolutionary dilemma, because cells with a higher rate but lower yield of ATP production may gain a selective advantage when competing for shared energy resources. Using an analysis of model simulations and biochemical observations, we show that ATP production with a low rate and high yield can be viewed as a form of cooperative resource use and may evolve in spatially structured environments. Furthermore, we argue that the high ATP yield of respiration may have facilitated the evolutionary transition from unicellular to undifferentiated multicellular organisms.
Laser Altimetry of Small-Scale Features on 433 Eros from NEAR-Shoemaker
Authors: Cheng Andrew F. , Barnouin-Jha Olivier , Zuber Maria T. , Veverka Joseph , Smith David E. , Neumann Gregory A. , Robinson Mark , Thomas Peter , Garvin James B. , Murchie Scott , Chapman Clark , Prockter Louise
Published: November 2007

During the Near Earth Asteroid Rendezvous (NEAR)–Shoemaker's low-altitude flyover of asteroid 433 Eros, observations by the NEAR Laser Rangefinder (NLR) have helped to characterize small-scale surface features. On scales from meters to hundreds of meters, the surface has a fractal structure with roughness dominated by blocks, structural features, and walls of small craters. This fractal structure suggests that a single process, possibly impacts, dominates surface morphology on these scales.
Imaging of Small-Scale Features on 433 Eros from NEAR: Evidence for a Complex Regolith
Authors: Veverka J. , Thomas P. C. , Robinson M. , Murchie S. , Chapman C. , Bell M. , Harch A. , Merline W. J. , Bell J. F. , Bussey B. , Carcich B. , Cheng A. , Clark B. , Domingue D. , Dunham D. , Farquhar R. , Gaffey M. J. , Hawkins E. , Izenberg N. , Joseph J. , Kirk R. , Li H. , Lucey P. , Malin M. , McFadden L. , Miller J. K. , Owen W. M. , Peterson C. , Prockter L. , Warren J. , Wellnitz D. , Williams B. G. , Yeomans D. K.
Published: November 2007

On 25 October 2000, the Near Earth Asteroid Rendevous (NEAR)–Shoemaker spacecraft executed a low-altitude flyover of asteroid 433 Eros, making it possible to image the surface at a resolution of about 1 meter per pixel. The images reveal an evolved surface distinguished by an abundance of ejecta blocks, a dearth of small craters, and smooth material infilling some topographic lows. The subdued appearance of craters of different diameters and the variety of blocks and different degrees of their burial suggest that ejecta from several impact events blanketed the region imaged at closest approach and led to the building up of a substantial and complex regolith consisting of fine materials and abundant meter-sized blocks.
Probing the Structure of Metal Cluster-Adsorbate Systems with High-Resolution Infrared Spectroscopy
Authors: Nauta K. , Moore D. T. , Stiles P. L. , Miller R. E.
Published: November 2007

High-resolution infrared laser spectroscopy was used to obtain rotationally resolved infrared spectra of adsorbate-metal complexes. The method involves forming the bare metal clusters in helium nanodroplets and then adding a molecular adsorbate (HCN) and recording the infrared spectrum associated with the C-H stretching vibration. Rotationally resolved spectra were obtained for HCN-Mgn(n= 1 to 4). The results suggest a qualitative change in the adsorbate–metal cluster bonding with cluster size.
Self-Assembly of Subnanometer-Diameter Single-Wall MoS
2
Nanotubes
Authors: Remskar Maja , Mrzel Ales , Skraba Zora , Jesih Adolf , Ceh Miran , Demšar Jure , Stadelmann Pierre , Lévy Francis , Mihailovic Dragan
Published: November 2007

We report on the synthesis, structure, and self-assembly of single-wall subnanometer-diameter molybdenum disulfide tubes. The nanotubes are up to hundreds of micrometers long and display diverse self-assembly properties on different length scales, ranging from twisted bundles to regularly shaped “furry” forms. The bundles, which contain interstitial iodine, can be readily disassembled into individual molybdenum disulfide nanotubes. The synthesis was performed using a novel type of catalyzed transport reaction including C
60
as a growth promoter.
Fecundity-Survival Trade-Offs and Parental Risk-Taking in Birds
Authors: Ghalambor Cameron K. , Martin Thomas E.
Published: November 2007

Life history theory predicts that parents should value their own survival over that of their offspring in species with a higher probability of adult survival and fewer offspring. We report that Southern Hemisphere birds have higher adult survival and smaller clutch sizes than Northern Hemisphere birds. We subsequently manipulated predation risk to adults versus offspring in 10 species that were paired between North and South America on the basis of phylogeny and ecology. As predicted, southern parents responded more strongly to reduce mortality risk to themselves even at a cost to their offspring, whereas northern parents responded more strongly to reduce risk to their offspring even at greater risk to themselves.
astray
, a Zebrafish
roundabout
Homolog Required for Retinal Axon Guidance
Authors: Fricke Cornelia , Lee Jeong-Soo , Geiger-Rudolph Silke , Bonhoeffer Friedrich , Chien Chi-Bin
Published: November 2007

As growing retinotectal axons navigate from the eye to the tectum, they sense guidance molecules distributed along the optic pathway. Mutations in the zebrafish
astray
gene severely disrupt retinal axon guidance, causing anterior-posterior pathfinding defects, excessive midline crossing, and defasciculation of the retinal projection. Eye transplantation experiments show that
astray
function is required in the eye. We identify
astray
as zebrafish
robo2
, a member of the Roundabout family of axon guidance receptors. Retinal ganglion cells express
robo2
as they extend axons. Thus,
robo2
is required for multiple axon guidance decisions during establishment of the vertebrate visual projection.
Targeting of HIF-α to the von Hippel-Lindau Ubiquitylation Complex by O
2
-Regulated Prolyl Hydroxylation
Authors: Jaakkola Panu , Mole David R. , Tian Ya-Min , Wilson Michael I. , Gielbert Janine , Gaskell Simon J. , Kriegsheim Alexander von , Hebestreit Holger F. , Mukherji Mridul , Schofield Christopher J. , Maxwell Patrick H. , Pugh ‡ Christopher W. , Ratcliffe ‡ Peter J.
Published: November 2007

Hypoxia-inducible factor (HIF) is a transcriptional complex that plays a central role in the regulation of gene expression by oxygen. In oxygenated and iron replete cells, HIF-α subunits are rapidly destroyed by a mechanism that involves ubiquitylation by the von Hippel–Lindau tumor suppressor (pVHL) E3 ligase complex. This process is suppressed by hypoxia and iron chelation, allowing transcriptional activation. Here we show that the interaction between human pVHL and a specific domain of the HIF-1α subunit is regulated through hydroxylation of a proline residue (HIF-1α P564) by an enzyme we have termed HIF-α prolyl-hydroxylase (HIF-PH). An absolute requirement for dioxygen as a cosubstrate and iron as cofactor suggests that HIF-PH functions directly as a cellular oxygen sensor.
HIFα Targeted for VHL-Mediated Destruction by Proline Hydroxylation: Implications for O
2
Sensing
Authors: Ivan Mircea , Kondo Keiichi , Yang Haifeng , Kim William , Valiando Jennifer , Ohh Michael , Salic Adrian , Asara John M. , Lane William S. , Kaelin Jr. William G.
Published: November 2007

HIF (hypoxia-inducible factor) is a transcription factor that plays a pivotal role in cellular adaptation to changes in oxygen availability. In the presence of oxygen, HIF is targeted for destruction by an E3 ubiquitin ligase containing the von Hippel–Lindau tumor suppressor protein (pVHL). We found that human pVHL binds to a short HIF-derived peptide when a conserved proline residue at the core of this peptide is hydroxylated. Because proline hydroxylation requires molecular oxygen and Fe
2+
, this protein modification may play a key role in mammalian oxygen sensing.
Expanding the Genetic Code of
Escherichia coli
Authors: Wang Lei , Brock Ansgar , Herberich Brad , Schultz Peter G.
Published: November 2007

A unique transfer RNA (tRNA)/aminoacyl-tRNA synthetase pair has been generated that expands the number of genetically encoded amino acids in
Escherichia coli
. When introduced into
E. coli
, this pair leads to the in vivo incorporation of the synthetic amino acid
O
-methyl-
l
-tyrosine into protein in response to an amber nonsense codon. The fidelity of translation is greater than 99%, as determined by analysis of dihydrofolate reductase containing the unnatural amino acid. This approach should provide a general method for increasing the genetic repertoire of living cells to include a variety of amino acids with novel structural, chemical, and physical properties not found in the common 20 amino acids.
Observation of Vortex Lattices in Bose-Einstein Condensates
Authors: Abo-Shaeer J. R. , Raman C. , Vogels J. M. , Ketterle W.
Published: November 2007

Quantized vortices play a key role in superfluidity and superconductivity. We have observed the formation of highly ordered vortex lattices in a rotating Bose-condensed gas. These triangular lattices contained over 100 vortices with lifetimes of several seconds. Individual vortices persisted up to 40 seconds. The lattices could be generated over a wide range of rotation frequencies and trap geometries, shedding light on the formation process. Our observation of dislocations, irregular structure, and dynamics indicates that gaseous Bose-Einstein condensates may be a model system for the study of vortex matter.
A Bose-Einstein Condensate of Metastable Atoms
Authors: Robert A. , Sirjean O. , Browaeys A. , Poupard J. , Nowak S. , Boiron D. , Westbrook C. I. , Aspect A.
Published: November 2007

We report the realization of a Bose-Einstein condensate of metastable atoms (helium in the lowest triplet state). The excitation energy of each atom with respect to the ground state is 20 electron volts, but inelastic processes that would destroy the sample are suppressed strongly enough in a spin-polarized sample to allow condensation. Our detection scheme takes advantage of the metastability to achieve detection of individual atoms as well as of the decay products of inelastic processes. This detection opens the way toward new studies in mesoscopic quantum statistical physics, as well as in atomic quantum optics.
Nota Bene: A Last Hurrah and New Directions
Authors: Chong Lisa
Published: November 2007

Molecular Cloning
A Laboratory Manual, 3rd ed. Joseph Sambrook and David W. Russell. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, 2001. 3 vols., 2288 pp. $295, £231. ISBN 0-87969-576-5. Paper, $195, £149. ISBN 0-87969-577-3.

This new edition of a classic compendium of protocols for biomolecular research is accompanied by a Web site that represents the likely future of efforts to provide researchers and students with up-to-date descriptions of reliable methods for carrying out experiments.
Computational Design of Peptides That Target Transmembrane Helices
Authors: Yin Hang , Slusky Joanna S. , Berger Bryan W. , Walters Robin S. , Vilaire Gaston , Litvinov Rustem I. , Lear James D. , Caputo Gregory A. , Bennett Joel S. , DeGrado William F.
Published: November 2007

A variety of methods exist for the design or selection of antibodies and other proteins that recognize the water-soluble regions of proteins; however, companion methods for targeting transmembrane (TM) regions are not available. Here, we describe a method for the computational design of peptides that target TM helices in a sequence-specific manner. To illustrate the method, peptides were designed that specifically recognize the TM helices of two closely related integrins (α
IIb
β
3
and α
v
β
3
) in micelles, bacterial membranes, and mammalian cells. These data show that sequence-specific recognition of helices in TM proteins can be achieved through optimization of the geometric complementarity of the target-host complex.
Permissive and Instructive Anterior Patterning Rely on mRNA Localization in the Wasp Embryo
Authors: Brent Ava E. , Yucel Gozde , Small Stephen , Desplan Claude
Published: November 2007

The long-germ mode of embryogenesis, in which segments arise simultaneously along the anteriorposterior axis, has evolved several times in different lineages of the holometabolous, or fully metamorphosing, insects.
Drosophila
's long-germ fate map is established largely by the activity of the dipteran-specific Bicoid (Bcd) morphogen gradient, which operates both instructively and permissively to accomplish anterior patterning. By contrast, all nondipteran long-germ insects must achieve anterior patterning independently of
bcd
. We show that
bcd
's permissive function is mimicked in the wasp by a maternal repression system in which anterior localization of the wasp ortholog of
giant
represses anterior expression of the trunk gap genes so that head and thorax can properly form.
Materials for Aesthetic, Energy-Efficient, and Self-Diagnostic Buildings
Authors: Fernández John E.
Published: November 2007

It has become desirable to reduce the nonrenewable content and energy footprint of the built environment and to develop “smart buildings” that allow for inexpensive monitoring and self-diagnostic capabilities. Latest-generation embedded sensors, self-healing composites, and nanoscale and responsive materials may augur a time when buildings can substantially adjust to changing environmental and functional demands. However, faced with the legal liability resulting from unknown lifetime performance, designers and engineers have had little incentive to incorporate new material technologies into building designs. As efficiency issues become more acute, the potential for improvement in performance from new materials, together with partnerships between the materials science community and those entrusted with the design and engineering of the built environment, may offer real breakthroughs for the future.
Plastic Deformation Recovery in Freestanding Nanocrystalline Aluminum and Gold Thin Films
Authors: Rajagopalan Jagannathan , Han Jong H. , Saif M. Taher A.
Published: November 2007

In nanocrystalline metals, lack of intragranular dislocation sources leads to plastic deformation mechanisms that substantially differ from those in coarse-grained metals. However, irrespective of grain size, plastic deformation is considered irrecoverable. We show experimentally that plastically deformed nanocrystalline aluminum and gold films with grain sizes of 65 nanometers and 50 nanometers, respectively, recovered a substantial fraction (50 to 100%) of plastic strain after unloading. This recovery was time dependent and was expedited at higher temperatures. Furthermore, the stress-strain characteristics during the next loading remained almost unchanged when strain recovery was complete. These observations in two dissimilar face-centered cubic metals suggest that strain recovery might be characteristic of other metals with similar grain sizes and crystalline packing.
Regulation of Hepatic Stellate Cell Differentiation by the Neurotrophin Receptor p75
NTR
Authors: Passino Melissa A. , Adams Ryan A. , Sikorski Shoana L. , Akassoglou Katerina
Published: November 2007

Differentiation of hepatic stellate cells (HSCs) to extracellular matrix– and growth factor–producing cells supports liver regeneration through promotion of hepatocyte proliferation. We show that the neurotrophin receptor p75
NTR
, a tumor necrosis factor receptor superfamily member expressed in HSCs after fibrotic and cirrhotic liver injury in humans, is a regulator of liver repair. In mice, depletion of p75
NTR
exacerbated liver pathology and inhibited hepatocyte proliferation in vivo.

p75
NTR

–/–
HSCs failed to differentiate to myofibroblasts and did not support hepatocyte proliferation. Moreover, inhibition of p75
NTR
signaling to the small guanosine triphosphatase Rho resulted in impaired HSC differentiation. Our results identify signaling from p75
NTR
to Rho as a mechanism for the regulation of HSC differentiation to regeneration-promoting cells that support hepatocyte proliferation in the diseased liver.
Seismostratigraphy and Thermal Structure of Earth's Core-Mantle Boundary Region
Authors: van der Hilst R. D. , de Hoop M. V. , Wang P. , Shim S.-H. , Ma P. , Tenorio L.
Published: November 2007

We used three-dimensional inverse scattering of core-reflected shear waves for large-scale, high-resolution exploration of Earth's deep interior (D″) and detected multiple, piecewise continuous interfaces in the lowermost layer (D″) beneath Central and North America. With thermodynamic properties of phase transitions in mantle silicates, we interpret the images and estimate in situ temperatures. A widespread wave-speed increase at 150 to 300 kilometers above the coremantle boundary is consistent with a transition from perovskite to postperovskite. Internal D″ stratification may be due to multiple phase-boundary crossings, and a deep wave-speed reduction may mark the base of a postperovskite lens about 2300 kilometers wide and 250 kilometers thick. The core-mantle boundary temperature is estimated at 3950 ± 200 kelvin. Beneath Central America, a site of deep subduction, the D″ is relatively cold (ΔT = 700 ± 100 kelvin). Accounting for a factor-of-two uncertainty in thermal conductivity, core heat flux is 80 to 160 milliwatts per square meter (mW m
–2
) into the coldest D″ region and 35 to 70 mW m
–2
away from it. Combined with estimates from the central Pacific, this suggests a global average of 50 to 100 mW m
–2
and a total heat loss of 7.5 to 15 terawatts.
Top-Down Versus Bottom-Up Control of Attention in the Prefrontal and Posterior Parietal Cortices
Authors: Buschman Timothy J. , Miller Earl K.
Published: November 2007

Attention can be focused volitionally by “top-down” signals derived from task demands and automatically by “bottom-up” signals from salient stimuli. The frontal and parietal cortices are involved, but their neural activity has not been directly compared. Therefore, we recorded from them simultaneously in monkeys. Prefrontal neurons reflected the target location first during top-down attention, whereas parietal neurons signaled it earlier during bottom-up attention. Synchrony between frontal and parietal areas was stronger in lower frequencies during top-down attention and in higher frequencies during bottom-up attention. This result indicates that top-down and bottom-up signals arise from the frontal and sensory cortex, respectively, and different modes of attention may emphasize synchrony at different frequencies.
Emergent Biogeography of Microbial Communities in a Model Ocean
Authors: Follows Michael J. , Dutkiewicz Stephanie , Grant Scott , Chisholm Sallie W.
Published: November 2007

A marine ecosystem model seeded with many phytoplankton types, whose physiological traits were randomly assigned from ranges defined by field and laboratory data, generated an emergent community structure and biogeography consistent with observed global phytoplankton distributions. The modeled organisms included types analogous to the marine cyanobacterium
Prochlorococcus
. Their emergent global distributions and physiological properties simultaneously correspond to observations. This flexible representation of community structure can be used to explore relations between ecosystems, biogeochemical cycles, and climate change.
Cascading Effects of the Loss of Apex Predatory Sharks from a Coastal Ocean
Authors: Myers Ransom A. , Baum Julia K. , Shepherd Travis D. , Powers Sean P. , Peterson Charles H.
Published: November 2007

Impacts of chronic overfishing are evident in population depletions worldwide, yet indirect ecosystem effects induced by predator removal from oceanic food webs remain unpredictable. As abundances of all 11 great sharks that consume other elasmobranchs (rays, skates, and small sharks) fell over the past 35 years, 12 of 14 of these prey species increased in coastal northwest Atlantic ecosystems. Effects of this community restructuring have cascaded downward from the cownose ray, whose enhanced predation on its bay scallop prey was sufficient to terminate a century-long scallop fishery. Analogous top-down effects may be a predictable consequence of eliminating entire functional groups of predators.
Ballistic Electron Microscopy of Individual Molecules
Authors: Bannani Amin , Bobisch Christian , Möller Rolf
Published: November 2007

We analyzed the transport of ballistic electrons through organic molecules on uniformly flat surfaces of bismuth grown on silicon. For the fullerene C
60
and for a planar organic molecule (3,4,9,10-perylene-tetracarboxylic acid dianhydride), the signals revealed characteristic submolecular patterns that indicated where ballistic transport was enhanced or attenuated. The transport was associated to specific electronic molecular states. At electron energies of a few electron volts, this “scanning near-field electron transmission microscopy” method could be applied to various adsorbates or thin layers.
What Flowed from "Surveys Say..."
Authors: Smith Tom W.
Published: November 2007

The Averaged American
. Surveys, Citizens, and the Making of a Mass Public.
By Sarah E. Igo
. Harvard University Press, Cambridge, MA, 2007. 408 pp. $35, £22.95, €32.30. ISBN 9780674023215.

Igo explores how the spread of information collected through quantitative social studies--public opinion polls, "man-in-the-street" interviews, sex surveys, community studies, and consumer research--transformed U.S. culture.
How Far Can We Go with Reason?
Authors: Sternberg Robert J.
Published: November 2007

How We Reason
.
By Philip N. Johnson-Laird
. Oxford University Press, Oxford, 2006. 583 pp. $57.50, £29.95. ISBN 9780198569763.

Drawing on his lifetime of experimentation and reflection on the psychology of reasoning, Johnson-Laird presents a comprehensive account of his mental model theory.
FEEDBACK CONTROL SYSTEM FOR SOFTWARE
Authors: SCHNEIDEWIND NORMAN
Published: November 2007

Feedback control systems are used in many walks of life, including automobiles, airplanes, and nuclear reactors. These are all physical systems, albeit with a considerable does of software. It occurred to us that there is no reason that feedback control systems could not be applied to the software process, specifically dealing with reliability analysis, test, and prediction. Thus, we constructed a model of such a system and analyzed whether feedback control, in the form of error signals representing deviations from desired behavior, could bring observed behavior in conformance with specifications. To conduct the experiment, we used NASA Space Shuttle software failure data and analyzed the feedback when no faults were removed versus removing faults. In making this evaluation two software reliability models were used: the Musa Logarithmic Model and the Schneidewind Model. In general, feedback based on fault removal allowed the software reliability process to provide more accurate predictions and, hence, finer control over the process.
SEGMENTED POINT PROCESS MODELS FOR MAINTAINED SYSTEMS
Authors: SYAMSUNDAR A. , NAIKAN V. N. A.
Published: November 2007

A maintained system is generally modeled using point processes. The most common processes used are the renewal process and the non homogeneous Poisson process corresponding to maximal and minimal repair situations with homogeneous Poisson process being a special case of both. A general repair formulation with a factor indicating the degree of repair is introduced into the minimal repair model to form an Arithmetic Reduction of Intensity model. These processes are generally able to model maintained systems with a fair degree of accuracy when the system is operating under stable conditions. However whenever there is a change in the environment these models which are monotonic in nature are not able to accommodate this change. Such systems operating under different environments need to be modelled by segmented models with the system domain divided into segments at the points of changes in the environment. The individual segments can then be modeled by any of the above point process models and these can be combined to form a composite model. This paper proposes a statistical model of such an operating/maintenance environment. Its purpose is to quantify the impacts of changes in the environment on the failure intensities. Field data from an industrial-setting demonstrate that appropriate parameter estimates for such phenomena can be obtained and such models are shown to more accurately describe the maintained system in a changing environment than the single point process models usually used.
EFFECTIVE COMPONENT IMPORTANCE ANALYSIS FOR THE MAINTENANCE OF SYSTEMS WITH COMMON-CAUSE FAILURES
Authors: XING LIUDONG , AMARI SUPRASAD V.
Published: November 2007

In this paper, we consider the component importance analysis of coherent systems subject to common-cause failures. The purpose of component importance analysis is to obtain information regarding a component's contribution or importance to the system reliability. The results from the component importance analysis are key contributors to the system design, tuning, and maintenance activities. Various measures have been proposed for the component importance analysis, but little work has been done to compare their performance. In this research, we investigate and compare a set of nine existing importance measures and select the most informative and appropriate one for guiding the system maintenance activity. An important concern in the traditional fault tree reliability analysis, common-cause failures, is also considered in the component importance analysis. An example is designed and analyzed to show the selection process and to illustrate our efficient method for considering the effects of common-cause failures in the component importance analysis.
ARCHITECTURE-BASED SOFTWARE RELIABILITY ANALYSIS INCORPORATING CONCURRENCY
Authors: EL KHARBOUTLY REHAB A. , GOKHALE SWAPNA S. , AMMAR REDA A.
Published: November 2007

With the growing complexity of software applications and increasing reliance on the services provided by these applications, architecture-based reliability analysis has become the focus of several recent research efforts. Most of the prevalent research in this area does not consider simultaneous or concurrent execution of application components. Concurrency, however, may be common in modern software applications. Thus, reliability analysis considering concurrent component execution within the context of the application architecture is necessary for contemporary software applications. This paper presents an architecture-based reliability analysis methodology for concurrent software applications. Central to the methodology is a state space approach, based on discrete time Markov chains (DTMCs), to represent the application architecture taking into consideration simultaneous component execution. A closed form, analytical expression for the expected application reliability based on the average execution times, constant failure rates, and the average number of visits to the components is derived. The average number of visits to application components are obtained from the solution of the DTMC model representing the application architecture. The potential of the methodology to facilitate sensitivity analysis, identification of reliability bottlenecks, and an assessment of the impact of workload and component changes, in addition to providing a reliability estimate, is discussed. To enable the application of the methodology in practice, estimation of model parameters from different software artifacts is described. The methodology is illustrated with a case study. Finally, strategies to alleviate the state space explosion issue for an efficient application of the methodology are proposed.
HUMAN RELIABITIY AND FLIGHT SAFETY
Authors: AFRAZEH ABBAS , BARTSCH HEINZ
Published: November 2007

This paper through a systematic view considers the subject of Airplane — Flight crew system, as an intricate system of Man and Machine. And we study its Reliability on Flight Safety with an emphasis on Human factor. Aiming at the above goals.

As we define the constituents of the system from a Socio-Technical perspective, introduce main factors involved in brining about Human errors in such a system. Finally we discuss the methods and procedures for the reduction of these errors which leads eventually to the promotion of Human reliability and consequently the Flight Safety.
Inherited Arrhythmias
Authors: Lehnart Stephan E. , Ackerman Michael J. , Benson D. Woodrow , Brugada Ramon , Clancy Colleen E. , Donahue J. Kevin , George Alfred L. , Grant Augustus O. , Groft Stephen C. , January Craig T. , Lathrop David A. , Lederer W. Jonathan , Makielski Jonathan C. , Mohler Peter J. , Moss Arthur , Nerbonne Jeanne M. , Olson Timothy M. , Przywara Dennis A. , Towbin Jeffrey A. , Wang Lan-Hsiang , Marks Andrew R.
Published: November 2007

The National Heart, Lung, and Blood Institute and Office of Rare Diseases at the National Institutes of Health organized a workshop (September 14 to 15, 2006, in Bethesda, Md) to advise on new research directions needed for improved identification and treatment of rare inherited arrhythmias. These included the following: (1) Na
+
channelopathies; (2) arrhythmias due to K
+
channel mutations; and (3) arrhythmias due to other inherited arrhythmogenic mechanisms. Another major goal was to provide recommendations to support, enable, or facilitate research to improve future diagnosis and management of inherited arrhythmias. Classifications of electric heart diseases have proved to be exceedingly complex and in many respects contradictory. A new contemporary and rigorous classification of arrhythmogenic cardiomyopathies is proposed. This consensus report provides an important framework and overview to this increasingly heterogeneous group of primary cardiac membrane channel diseases. Of particular note, the present classification scheme recognizes the rapid evolution of molecular biology and novel therapeutic approaches in cardiology, as well as the introduction of many recently described diseases, and is unique in that it incorporates ion channelopathies as a primary cardiomyopathy in consensus with a recent American Heart Association Scientific Statement.
An International Conscience Collective? A Durkheimian Analysis of International Criminal Law
Authors: Nimaga Salif
Published: November 2007

This socio-legal approach to international criminal law is informed by the writings of Émile Durkheim, one of the founding fathers of (legal) sociology. On the basis of a comprehensive review of primary sources and recent developments in secondary writings, Durkheim's understanding of criminal law and its sanctioning process are reconstructed. From this perspective the international criminal justice system is analysed both directly and indirectly. The first is a sociological interpretation that perceives international criminal law as being rooted in the cult of the individual. The second brings a clarification of the function international criminal tribunals perform and concludes that this cannot be adequately appraised with regard to effects on individuals or nation-states but only with regard to an emerging global society. This highly original investigation is a demonstration of the enduring relevance of Durkheim's oeuvre and a contribution to the developing diversification of theoretical perspectives on international criminal law.
The European Union and the International Criminal Court: An Awkward Symbiosis in Interesting Times
Authors: Bekou Olympia , Antoniadis Antonis
Published: November 2007

The aim of this article is to provide an overview and to evaluate the EU-ICC partnership. The analysis includes the measures the EU has taken to commit to the ICC cause and implement the Rome Statute and their impact on EU policy-making. These include the EU-ICC Cooperation Agreement as well as EU Third Pillar measures affecting Member State cooperation with the ICC and governing the investigation and prosecution of crimes within the jurisdiction of the ICC. The issue of judicial protection and respect of fundamental rights in the EU under the Third Pillar will also be addressed. Finally, the analysis of EU initiatives, primarily in its relations with third countries, to preserve the universality and integrity of the Rome Statute will follow.
The Dissonance between the United Nations Zero-Tolerance Policy and the Criminalisation of Sexual Offences on the International Level
Authors: Quénivet Noëlle
Published: November 2007

As a growing number of stories unravelled the involvement of United Nations peacekeepers in human trafficking and sexual exploitation cases, the United Nations adopted in 2003 and implemented a zero-tolerance policy towards sexual encounters between peacekeepers and local women. This article argues that this policy is flawed for a number of reasons. First, it does not apply to all United Nations-related personnel and thereby fails to target those who are mostly engaged in such activities. Second, it only provides for disciplinary measures, a flaw only partially remedied by the draft convention on the criminal accountability of United Nations officials and experts on mission. Third, it does not take into account the jurisprudence of international criminal tribunals on sexual offences, for it negates the possibility of consent.
Familiarity and threat of opponents determine variation in Thomas langur (Presbytis thomasi) male behaviour during between-group encounters
Authors: Wich Serge , Sterck Elisabeth
Published: November 2007

During between-group encounters in primates, males often defend mates, food or infants against other males. Males, however, show variation in contests between opponents. In other taxa, such variation has been attributed to variation in familiarity with or threat of opponents. Here we present the results of analyses of between-group encounter intensity variation in Thomas langurs while controlling for threat when evaluating familiarity and vice versa. Encounter intensity was measured by the proportion of encounters with chases and the number of loud calls per minute during the encounter given by the focal male. The results indicate that both familiarity and threat influence encounter intensity. Less familiar opponents had more intense encounters and opponents that differed in the threat level to each other also had more intense encounters. Thus, Thomas langur males seem to incorporate information on both the level of threat and familiarity of other males to make a decision on how to react during a between-group encounter.
Factors affecting individual participation in group-level aggression among non-human primates
Authors: Beehner Jacinta , Kitchen Dawn
Published: November 2007

Group members do not always act cohesively when facing extra-group rivals. When benefits such as group-defence are not monopolizable, it poses an economics problem: who should contribute to public goods and who should freeload? A collective action framework compliments existing theoretical explanations for cooperation, and provides testable hypotheses about group-level behaviour based on individual costs and benefits. Using this approach, we review research on intergroup encounters in non-human primates published over the last 20 years, focusing on participation by different classes of individuals. While food- and mate-defence explain much between-sex variation in participation, rank and reproductive access frequently explain within-sex variation. In some species, individuals may use intergroup interactions to survey potential transfer locations and mating options, which might coincidently intimidate rivals. Experimental evidence suggests that when intergroup dominance is based on relative number of fighters, individual participation still varies with sex, rank, companion behaviour and dependent offspring presence. Relatively few studies have examined how factors such as relationships within and between groups or individual temperament mediate aggression. Long-term studies of multiple habituated groups and methodological advances (e.g., playback experiments) will continue to improve our understanding of how complex group-level patterns are predictable when viewed from an individual perspective.
Use of overlap zones among group-living primates: a test of the risk hypothesis
Authors: Wrangham Richard , Lundy Rochelle , Crofoot Meg , Gilby Ian
Published: November 2007

Overlap zones between home ranges of neighboring groups of primates are routinely reported to be under-used. However, little is known about how the size of overlap zones varies, or what factors influence their size. Here we use ranging data on three species of group-living primates to test the hypothesis that overlap zones are smaller or used less in species that are subject to a higher risk of lethal aggression in intergroup encounters. Redtail monkeys (Cercopithecus ascanius) have a low risk of violence; white-faced capuchins (Cebus capucinus) have an intermediate risk; chimpanzees (Pan troglodytes) face a high risk of violent encounters with their neighbors. We calculated two indices of use of the overlap zone. First, we assessed the opportunity for groups to meet each other as the range overlap, i.e., the diameter of the home range in relation to the distance between neighboring ranges. Second, we compared the intensity with which groups used the overlap zone by calculating utilization curves that described how space-use patterns change with distance from a group's center of activity. Neither the overlap potentials nor utilization curves supported the risk hypothesis. There was little evidence of differences among the three species, all of which showed substantial under-use of overlap zones. Our data, which provide the first systematic comparison of overlap zones among primates, thus conform to previous reports suggesting that primate groups tend to have large overlap zones, regardless of the risk of violence. Since such zones are potentially responsible for carrying capacity being lower than expected by an ideal-free distribution, it is an important problem to understand why they are apparently widespread.
Variable participation in the defense of communal feeding territories by blue monkeys in the Kakamega Forest, Kenya
Authors: Cords Marina
Published: November 2007

While blue monkey groups often defend feeding territories against their neighbours, group members do not participate equally. Data spanning 5 years and 5 wild groups were used to address factors that might explain variable participation, both across age-sex classes and among individual adult females. Adult females participated most, although there was a 9-fold difference between those individuals who participated most and least. Juvenile participation increased with age, but female juveniles participated more than males in each cohort. Male juveniles reduced participation as they approached the age of natal emigration. In general, it seems that adult participation patterns are acquired gradually during ontogeny. Among adult females, those with infants participated less than those without infants, and higher-ranking females participated more than lower-rankers. The presence of matrilineal kin in the group did not generally affect participation by adult females. Age-sex class differences and the effect of infant presence can be explained in terms of relative costs and benefits to participation. The lack of a kinship effect was unexpected. The rank effect was also unanticipated, given that rank does not predict reproductive success in this species. High-ranking females may face lower costs, offer staying incentives to lower-ranked females, or trade services with them.