cssi/SciSciGPT-SciSciNet huggingface dataset:
Vacancy clustering and prismatic dislocation loop formation in aluminum

The formation of prismatic dislocation loops is an important factor leading to radiation damage of metals. However, the formation mechanism and the size of the smallest stable loop has remained unclear. In this Rapid Communication, we use electronic structure calculations with millions of atoms to address this problem in aluminum. Our results show that there is a cascade of larger and larger vacancy clusters with smaller and smaller energy. Further, the results show that a seven vacancy cluster on the (111) plane can collapse into a stable prismatic loop. This supports the long-standing hypothesis that vacancy clustering leads to a prismatic loop, and that these loops can be stable at extremely small sizes. Finally our results show that it is important to conduct calculations using realistic concentrations (computational cell size) to obtain physically meaningful results.
Bromouracil-induced mutagenesis in a mismatch-repair-deficient strain of Haemophilus influenzae.

Abstract Cells of wild-type Haemophilus influenzae and of a mismatch-repair-deficient mutant (hex−) were grown in a chemically defined medium containing either thymidine or 5-bromodeoxyuridine (BUdR). Spontaneous mutation frequencies to resistance against 3 antibiotics observed for the thymidine cultures were 10–30 times higher for the hex− mutant. The mutation frequencies observed for the BUdR hex− culture were increased by another 10 times while those for the wild-type suspension did not differ from the frequencies seen in the thymidine medium.
Thrombin induced inhibition of neurite outgrowth from dorsal root ganglion neurons

Thrombin is a multifunctional protease. Recent studies on cultured neuronal cells have suggested a function for thrombin in the development and maintenance of the nervous system. Thrombin has been found to induce neurite retraction and reverse stellation in neuroblastoma cell lines and rat astrocytes, respectively. The major focus of our study was to investigate the potential role of thrombin in peripheral nervous system development using the rat embryonic dorsal root ganglion model. We found a dose dependent inhibition of neurite outgrowth from explant dorsal root ganglion cultures upon exposure to 2 to 200 nM thrombin. This effect was reversed by the specific thrombin inhibitor, hirudin. A synthetic peptide that imitates the fully active receptor, thrombin receptor activating peptide, was also found to inhibit neurite outgrowth from dorsal root ganglia. bis-Benzimide stained neuronal cultures did not show any evidence of cell death after exposure to thrombin or thrombin receptor activating peptides. Immunohistochemical studies revealed specific staining of the thrombin receptor on neurons, with intense labeling along neurites. Enriched neuronal cultures exposed to thrombin and thrombin receptor activating peptides revealed rapid activation of phospholipase Cγ-1, a second messenger associated with the thrombin receptor. These findings are the first to describe the localization of the thrombin receptor to dorsal root ganglion neurons. We propose that receptor activation is associated with thrombin induced inhibition of neurite outgrowth.
Limitations of risk score models in patients with acute chest pain

Abstract Objectives Cardiac multidetector computed tomography (CMCT) has potential to be used as a screening test for patients with acute chest pain, but several tools are already used to risk-stratify this population. Risk models exist that stratify need for intensive care (Goldman), short-term prognosis (Thrombolysis in Myocardial Infarction, TIMI), and 1-year events (Sanchis). We applied these cardiovascular risk models to candidates for CMCT and assessed sensitivity for prediction of in-hospital acute coronary syndrome (ACS). We hypothesized that none of the models would achieve a sensitivity of 90% or greater, thereby justifying use of CMCT in patients with acute chest pain. Methods We analyzed TIMI, Goldman, and Sanchis in 148 consecutive patients with chest pain, nondiagnostic electrocardiogram, and negative initial cardiac biomarkers who previously met inclusion and exclusion criteria for the Rule-Out Myocardial Infarction Using Coronary Artery Tomography Study. ACS was adjudicated, and risk scores were categorized based on established criteria. Risk score agreement was assessed with weighted κ statistics. Results Overall, 17 (11%) of 148 patients had ACS. For all risk models, sensitivity was poor (range, 35%-53%), and 95% confidence intervals did not cross above 77%. Agreement to risk-classify patients was poor to moderate (weighted κ range, 0.18-0.43). Patients categorized as "low risk" had nonzero rates of ACS using all 3 scoring models (range, 8%-9%). Conclusions Available risk scores had poor sensitivity to detect ACS in patients with acute chest pain. Because of the small number of patients in this data set, these findings require confirmation in larger studies.
A double partial melt zone in the mantle beneath mid-ocean ridges

For a lherzolite mantle with about 0.1 wt.-percent CO2 or less, and a CO2/H2O mole ratio greater than about one, the mantle solidus curve in P-T space will have two important low-temperature regions, one centered at about 9 kbar (30 km depth) and another beginning at about 28 kbar (90 km depth). It is argued that the depth of generation of primary tholeiitic magmas beneath ridge crests is about 9 kbar, and that the geotherm changes from an adiabatic gradient at greater pressures to a strongly superadiabatic gradient at lesser pressures. Such a ridge geotherm would intersect the solidus at two separate depth intervals corresponding to the two low-temperature regions on the solidus. With increasing age and cooling of the lithosphere, the shallow partial melt zone would pinch out and the thickness of the deep partial melt zone would decrease. With increasing depth in a mature oceanic lithosphere, the rock types would consist of depleted harzburgite from directly beneath the crust to about 30 km depth, fertile spinel lherzolite from about 30 km to 50–60 km, and fertile garnet lherzolite from about 50–60 km to the top of the deep partial melt zone at about 90 km.
Multicritical points in an Ising random-field model.

The phase diagram of the mean-field Ising model in a random field obeying a symmetric three-peak distribution is determined. This distribution is relevant to diluted antiferromagnets in a uniform magnetic field. The phase diagram includes a fourth-order point, tricritical points, ordered critical points, critical end points, and a double critical end point. An ordered phase persists for arbitrarily large random fields at low temperatures.
COMPRESSION NEUROPATHIES OF THE MEDIAN NERVE

Abstract Specific compression syndromes of the median nerve are known in the proximal forearm and at the wrist. Carpal tunnel syndrome is the best known and most common, but pronator teres syndrome and anterior interosseous nerve syndrome also are clinically significant. In this discussion, we review the history, relevant anatomy, diagnosis, and treatment modalities for these compression syndromes.
Sensitivity of a stripping analyser for neutral hydrogen atoms in the energy range from 50 to 300 eV

The sensitivity of a neutral-hydrogen energy analyser consisting of a gas-stripping cell and an electric ion analyser was investigated in the energy range from 50 to 300 eV. A neutral atom flux is produced by means of a plasma gun and multipole guide field. The density of this flux at the analyser entrance was determined using a calibrated secondary emission detector. The conversion efficiencies of various gases and their pressure dependence was examined. So far the use of oxygen as stripping gas seems to be the optimal choice. However, for all investigated stripping gases the sensitivity was found to be a steep function of the particle energy. This might limit the applicability of this analyser to energies above 100 eV, using the investigated gases for stripping. The overall energy resolution is estimated to be ΔE/E = 10 − 15%.
Label-Free DNA Detection Using Liquid Core Optical Ring Resonators

We present a novel label-free method of quantifying single stranded DNA concentrations in solution using the Liquid Core Optical Ring Resonator (LCORR). The LCORR is a glass capillary that is capable of evanescent sensing of analytes while providing fluidic delivery through its hollow core. An evanescent field is excited in the ring-shaped circumference of the LCORR by externally coupled photons, which circulate via total internal reflection in the form of Whispering Gallery Modes (WGM's). When the wall of the capillary is etched to under 5 μm, the evanescent field from the WGM's is exposed in both the internal and external media. Chemical modification of the interior of the LCORR enables specific capture of target oligonucleotides by hybridization with a covalently bound probe. Refractive index changes at this interface are shown to produce a measurable change in the optical signal by shifting the resonance condition of the cavity. Real time kinetic analysis of the hybridization between the two complimentary strands is demonstrated as well as a thorough calibration of the sensor response to strand lengths between 25 and 100 bases and bulk concentration from 0.5 nM to 10 μM. Non-specific binding of completely mismatched oligonucleotides is shown to be minimal and single base mismatch detection is also demonstrated definitively.
Truncation of limonene synthase preprotein provides a fully active 'pseudomature' form of this monoterpene cyclase and reveals the function of the amino-terminal arginine pair.

The monoterpene cyclase limonene synthase transforms geranyl diphosphate to a monocyclic olefin and constitutes the simplest model for terpenoid cyclase catalysis. (−)-4S-Limonene synthase preprotein from spearmint bears a long plastidial targeting sequence. Difficulty expressing the full-length preprotein in Escherichia coli is encountered because of host codon usage, inclusion body formation, and the tight association of bacterial chaperones with the transit peptide. The purified preprotein is also kinetically impaired relative to the mixture of N-blocked native proteins produced in vivo by proteolytic processing in plastids. Therefore, the targeting sequence, that precedes a tandem pair of arginines (R58R59) which is highly conserved in the monoterpene synthases, was removed. Expression of this truncated protein, from a vector that encodes a tRNA for two rare arginine codons (pSBET), affords a soluble, tractable ‘pseudomature' form of the enzyme that is catalytically more efficient than the native spec...
Fundamental plant biology enabled by the Space Shuttle

The relationship between fundamental plant biology and space biology was especially synergistic in the era of the Space Shuttle. While all terrestrial organisms are influenced by gravity, the impact of gravity as a tropic stimulus in plants has been a topic of formal study for more than a century. And while plants were parts of early space biology payloads, it was not until the advent of the Space Shuttle that the science of plant space biology enjoyed expansion that truly enabled controlled, fundamental experiments that removed gravity from the equation. The Space Shuttle presented a science platform that provided regular science flights with dedicated plant growth hardware and crew trained in inflight plant manipulations. Part of the impetus for plant biology experiments in space was the realization that plants could be important parts of bioregenerative life support on long missions, recycling water, air, and nutrients for the human crew. However, a large part of the impetus was that the Space Shuttle enabled fundamental plant science essentially in a microgravity environment. Experiments during the Space Shuttle era produced key science insights on biological adaptation to spaceflight and especially plant growth and tropisms. In this review, we present an overview of plant science in the Space Shuttle era with an emphasis on experiments dealing with fundamental plant growth in microgravity. This review discusses general conclusions from the study of plant spaceflight biology enabled by the Space Shuttle by providing historical context and reviews of select experiments that exemplify plant space biology science.
Energies of line singularities in 3 He-A

We investigate a class of topologically equivalent line singularities in 3He-A to determine which of this class has the lowest free energy density. Most of our results concern the Landau-Ginzburg regime near T c ; we offer a speculation on what might occur further below T c .
MINORITY CARRIER INJECTION AND SERIES RESISTANCE EFFECTS IN HYDROGENATED AMORPHOUS SILICON SCHOTTKY BARRIER DIODES.

The minority-carrier injection and series resistance effects on the electrical properties of a-Si:H Schottky barrier diodes are described. The conductivity modulation was observed, for the first time, in metal/HOMOCVD a-Si:H contacts. Its effect on capacitance-voltage characteristics are discussed. The minority-carrier injection ratio is estimated from current-voltage characteristics as a function of total forward current for different metals. It is shown that these effects cannot be neglected in the interpretation of the AC and DC measurements. The caution, therefore, must be taken when using a-Si:H diodes structures to obtain the fundamental physical parameters characterizing either the interface or bulk properties of amorphous semiconductors.
Context-free fuzzy languages*

In an earlier paper (Santos, 1973b), the author introduced two distinct but equivalent formulations of max-product grammars. One corresponds to the maximal interpretation (Salomaa, 1969) of probabilistic grammars (Santos, 1972), while the other provides a grammar for generating fuzzy languages (Santos, 1973a). Various types of max-product grammars were given. Among them was the context-free max-product grammar (CMG). In the present paper, we shall study in detail the properties of CMG and languages generated by CMG. The main contents of the paper are contained in the next two sections. In Section II, the definitions of CMG and fuzzy languages generated by CMG are given. It is shown that every CMG may be put in Chomsky normal form and Greibach normal form (Hopcroft and Ullman, 1969) provided the fuzzy languages generated by the CMG are finitary. This forms the basis of all subsequent discussions. In Section III, various properties of languages generated by CMG with cut points are established. It is shown that the family A ° of languages generated by CMG with cut points contains the family of context-free languages as a proper subfamily. Moreover, it is shown that there exists a context-sensitive language which is not in Lf.
Minimum Angular-Impulse Control for a Large Flexible Spacecraft

Characterization and implementation of efficient rotational motions of flexible spacecraft have been of research interest for more than 20 years. In the present study we consider rest-to-rest pointing maneuvers for a very large spacecraft, so that limits on available angular momentum are paramount. A formal system of differential equations is developed based on a model that includes a rigid central hub and Euler-Bernoulli appendages. The model is recast in an appropriate state-space and standard functional analysis methods are used to prove well-posedness and to establish a framework for numerical approximation. Several variants of minimum-angular moment problems are studied; ultimately, we focus on a low-dimensional control parameterization based on a family of versine functions and on quasi-static structural response. Results are characterized in terms of simple formulas and sensitivity with respect to problem data is presented.
Crossover behavior in a two-dimensional electron gas and quasiplasma oscillation

The dynamic structure factor for a two-dimensional (2D) electron gas at $T=0$ is calculated by a method of recurrence relations. Our result indicates an interesting crossover behavior in going from interacting to noninteracting, which is unique to 2D electronic systems. The crossover behavior is characterized by a simple power law with a "classical" exponent, probably detectable by x rays. The validity of our result is tested against standard moment sum rules and also the static form-factor sum rule at high and low frequencies.
Question: How Should Middle East Studies Address the Issues of Academic Freedom and Academic Boycotts?

Challenges to academic freedom have been much in the news of late, with coverage and interest extending well beyond college newspapers and the publications of our profession.In the United States, there is no question that members of the Middle East studies community have been disproportionately targeted. A number of our colleagues have been victims of ugly smear campaigns regarding their scholarship; several tenure cases have triggered vicious, high-profile “extramural” attacks against junior faculty; and, in a handful of cases, our colleagues have been barred from giving talks or participating in educational events, owing to their political positions on Middle East-related issues. Others from outside this community who have also ventured to engage key regional issues in critical ways have had their invitations to give presentations in policy or academic forums rescinded.
Heat content variability in the North Atlantic Ocean in ocean reanalyses

Warming of the North Atlantic Ocean from the 1950s to 2012 is analyzed on neutral density surfaces and vertical levels in the upper 2000 m. Three reanalyses and two observational data sets are compared. The net gain of 5 × 1022 J in the upper 2000 m is roughly 30% of the global ocean warming over this period. Upper ocean heat content (OHC) is dominated in most regions by heat transport convergence without widespread changes in the potential temperature/salinity relation. The heat convergence is associated with sinking of midthermocline isopycnals, with maximum sinking occurring at potential densities σ0 = 26.4−27.3, which contain subtropical mode waters. Water masses lighter than σ0 = 27.3 accumulate heat by increasing their volume, while heavier waters lose heat by decreasing their volume. Spatially, the OHC trend is nonuniform: the low latitudes, 0–30°N are warming steadily while large multidecadal variability occurs at latitudes 30–65°N.
Ideational Learning and the Paradox of Chinese Catholic Reconciliation

During the 1980s, Chinese policy elites underwent a process of complex learning in economic policy that resulted in a shift from a revolutionary to a techno-economic paradigm that greatly reduced the control of the Chinese Communist Party over the economy. Spillover from the sectoral paradigm shift affected other policy sectors, which forced policy elites to experiment with religious policies that would complement the new economic paradigm. This experimentation fostered the growth of a civil society that could assume the social responsibilities cast off by the reforming state-owned enterprises. However, the experimentation also empowered distributional coalitions such as the Falungong, which threatened the party’s control. Policy elites thus implemented adaptations of religious policies formulated under the revolutionary paradigm. The study concludes that the current conflict between the Vatican and Beijing resembles an iterated prisoner’s dilemma and that the conflict will continue until Chinese policy elites realize that the failure of religious policy adaptations threaten the long-term goals of the techno-economic paradigm.
Adaptive tracking in distributed wireless sensor networks

We study the problem of tracking moving objects using distributed wireless sensor networks (WSNs) in which sensors are deployed randomly. Due to the uncertainty and unpredictability of real-world objects' motion, the tracking algorithm is needed to adapt to real-time changes of velocities and directions of a moving target. Moreover, the energy consumption of the tracking algorithm has to be considered because of the inherent limitations of wireless sensors. In this paper, we proposed an energy efficient tracking algorithm, called Predict-and-Mesh (PaM) that is well suited for pervasively monitoring various kinds of objects with random movement patterns. PaM is a distributed algorithm consisting of two prediction models: n-step prediction and collaborative prediction, and a predication failure recovery process called mesh. The simulation results show that the PaM algorithm is robust against diverse motion changes and has the excellent performance.
Exploiting Social Networks to Mitigate the Obesity Epidemic

Despite significant efforts, obesity continues to be a major public health problem, and there are surprisingly few effective strategies for its prevention and treatment. We now realize that healthy diet and activity patterns are difficult to maintain in the current physical environment. Recently, it was suggested that the social environment also contributes to obesity. Therefore, using network-based interaction models, we simulate how obesity spreads along social networks and predict the effectiveness of large-scale weight management interventions. For a wide variety of conditions and networks, we show that individuals with similar BMIs will cluster together into groups, and if left unchecked, current social forces will drive these groups toward increasing obesity. Our simulations show that many traditional weight management interventions fail because they target overweight and obese individuals without consideration of their surrounding cluster and wider social network. The popular strategy for dieting with friends is shown to be an ineffective long-term weight loss strategy, whereas dieting with friends of friends can be somewhat more effective by forcing a shift in cluster boundaries. Fortunately, our simulations also show that interventions targeting well-connected and/or normal weight individuals at the edges of a cluster may quickly halt the spread of obesity. Furthermore, by changing social forces and altering the behavior of a small but random assortment of both obese and normal weight individuals, highly effective network-driven strategies can reverse current trends and return large segments of the population to a healthier weight.
Tiresias: Black-Box Failure Prediction in Distributed Systems

Faults in distributed systems can result in errors that manifest in several ways, potentially even in parts of the system that are not collocated with the root cause. These manifestations often appear as deviations (or "errors") in performance metrics. By transparently gathering, and then identifying escalating anomalous behavior in, various node-level and system-level performance metrics, the Tiresias system makes black-box failure-prediction possible. Through the trend analysis of performance metrics, Tiresias provides a window of opportunity (look-ahead time) for system recovery prior to impending crash failures. We empirically validate the heuristic rules of the Tiresias system by analyzing fault-free and faulty performance data from a replicated middleware-based system.
Multicomponent vapor‐liquid equilibria at high pressures: Part I. Experimental study of the nitrogen—oxygen—carbon dioxide system at 0°C

A description is given of a dynamic vapor-liquid equilibrium apparatus in which both phases are recirculated by vane pumps especially designed for high-pressure service. Equilibrium phase compositions as well as vapor and liquid molar volumes up to the critical pressure are reported for the two binary systems nitrogen-carbon dioxide and oxygen-carbon dioxide and for the ternary.
Recent development in therapeutics for breakthrough pain

Breakthrough pain is defined as transitory flares of pain. Breakthrough pain is caused by cancer, cancer complications, treatment or comorbidities. The usual onset to maximum breakthrough pain intensity time is 3 min and duration is 30 min; therefore, the assessment for response needs to be at short intervals. The rapid onset and offset of pain results in inadequate responses when oral opioids are used to manage pain flares. Several strategies have been used to manage breakthrough pain: titration of the chronic opioid, independent titration of rescue opioids and alternative routes. Buccal fentanyl has a rapid onset to analgesia and appears to be superior to oral morphine. Newer fentanyl preparations have been released to manage breakthrough pain in the opioid-tolerant individual. Other routes of administration that have a rapid onset to analgesia include intranasal hydrophilic and lipophilic opioids, inhaled opioids delivered by special delivery devices and parenteral morphine. In a small series of patients experiencing severe flares of pain with spinal opioids unrelieved by parenteral opioids, sublingual ketamine and bolus doses of intrathecal local anesthetics have been effective. Nonpharmacological approaches to managing activity-related pain include radiation therapy, surgical correction of impending fractures, kyphoplasty and radioisotopes.
The role of presenilins in Alzheimer’s disease

In the past few years, 2 homologous polytopic membrane proteins termed presenilins (PSs) have been the focus of several research groups interested in the molecular mechanisms of Alzheimer’s disease (AD). Mutations in the Presenilin 1 (PS1) and Presenilin 2 (PS2) genes account for the majority of the cases of familial earlyonset AD (see the Perspective by Tanzi in the previous issue of the JCI). Analysis of PS1 null mice and other model systems reveals a role for PS1 in development. Furthermore, biochemical and genetic evidence indicate that PS1 plays an important role in facilitating the proteolytic processing of certain proteins, including amyloid precursor protein (APP) and Notch1. Mutant PS proteins influence the γ-secretase‐mediated processing of APP, cause a selective increase in the levels of highly fibrillogenic Aβ42 species, and accelerate Aβ deposition in the brains of transgenic mice. This apparent gain of function of mutant PS in AD seems to be distinct from the role of PS1 in development. Although PS1 interacts with several proteins, including members of the armadillo family of proteins, thus far none of the PS-interacting proteins have been shown to play a direct role in the enhanced production of Aβ42 mediated by mutant PS. This review focuses on the unusual and fascinating aspects of PS metabolism, its role in facilitating the trafficking and cleavage of a set of membrane-bound proteins, and its role in the pathogenesis of AD. The genetics and structure of the presenilins. Approximately 10% of all cases of Alzheimer’s disease (AD) are estimated to be early-onset familial AD (FAD) and show autosomal dominant inheritance. Mutations in the Presenilin 1 (PS1) gene and the related gene Presenilin 2 (PS2), located on chromosomes 14 and 1, respectively, are causative in approximately 50% of pedigrees with FAD. Since 1995, more than 50 different mutations in PS1 have been described in over 80 families of various ethnic origins with early-onset FAD. With 2 notable exceptions (one, a deletion of 30 amino acids, and the other, insertion of 1 amino acid), mutations in presenilins are missense substitutions that result in single amino acid changes. In contrast to PS1 mutations, thus far only 2 mutations in PS2 have been described. These alleles occur in families with variable onset, autosomal dominant FAD. PS1 is a 467‐amino acid polypeptide predicted to contain between 7 and 9 transmembrane-spanning domains and to include a hydrophilic “loop” region. A variety of biochemical and cell biologic approaches were used to determine the topology of PS1 and the Caenorhabditis elegans homologues SEL12 and HOP-1. These data generally predict that the NH2-terminus, the
Silicon Carbide Oxidation in High‐Pressure Steam

Silicon carbide is a candidate cladding for fission power reactors that can potentially provide better accident tolerance than zirconium alloys. SiC has also been discussed as a host matrix for nuclear fuel. Chemical vapor–deposited silicon carbide specimens were exposed in 0.34–2.07 MPa steam at low gas velocity (~50 cm/min) and temperatures from 1000°C to 1300°C for 2–48 h. As previously observed at lower steam pressure of 0.15 MPa, a two-layer SiO2 scale was formed during exposure to these conditions, composed of a porous cristobalite layer above a thin, dense amorphous SiO2 surface layer. Growth of both layers depends on temperature, time, and steam pressure. A quantitative kinetics model is presented to describe the SiO2 scale growth, whereby the amorphous layer is formed through a diffusion process and linearly consumed by an amorphous to crystalline phase transition process. Paralinear kinetics of SiC recession were observed after exposure in 0.34 MPa steam at 1200°C within 48 h. High-pressure steam environments are seen to form very thick (10–100 μm) cristobalite SiO2 layers on CVD SiC even after relatively short-term exposures (several hours). The crystalline SiO2 layer and SiC recession rate significantly depend on steam pressure. Another model is presented to describe the SiC recession rate in terms of steam pressure when a linear phase transition kl governing the recession kinetics, whereby the reciprocal of recession rate is found to follow a negative unity steam pressure power law.
Seasonal Eddy Field Modulation of the North Pacific Subtropical Countercurrent: TOPEX/Poseidon Observations and Theory

Altimetry data from the first 5…-yr TOPEX/Poseidon mission (October 1992‐December 1997) are analyzed focusing on the North Pacific Subtropical Countercurrent (STCC) near the center of the Pacific’s western subtropical gyre. The multiyear altimetry data reveal that the eastward-flowing STCC is a highly variable zonal current, whose area-averaged eddy kinetic energy level (338 cm 2 s22) reaches half the eddy kinetic energy level of the Kuroshio Extension. The eddy kinetic energy of the STCC has a well-defined annual cycle with a maximum in April/May and a minimum in December/January. The peak-to-peak amplitude of this seasonal eddy kinetic energy modulation exceeds 200 cm2 s22. No such distinct annual cycle of the eddy kinetic energy is found in any other zonal current of the North Pacific Ocean. Using a 2‰-layer reduced-gravity model representing the vertically sheared STCC‐North Equatorial Current (NEC) system, it is shown that the seasonal modulation of the STCC’s eddy field is a manifestation in the intensity of baroclinic instability. In spring the STCC‐NEC system has a large vertical velocity shear and a weak vertical stratification, subjecting it to strong baroclinic instability. In fall, reduction in the vertical velocity shear between the STCC and its underlying NEC, and intensification of the upper-layer stratification weakens the baroclinic instability. In comparison with the STCC of 198‐258N, the altimetry data reveal that the westward-flowing NEC existing between 10 8 and 158N has a relatively low eddy kinetic energy level, despite being a stronger vertically sheared zonal current than the STCC. That the NEC is less eddy energetic is shown to be due to both its presence in a low-latitude band and its unidirectional flow. Both of these factors make it more difficult to reverse the potential vorticity gradient of the mean state (i.e., satisfying the necessary condition for the baroclinic instability) in the NEC than in the STCC‐ NEC system.
Ultra-thin flexible microcircuit assemblies using thinned die and multilayer thin-film substrates

Ultra-thin, flexible microcircuit assemblies using thinned die (down to 20µm in thickness) and multilayer, thin film substrates (up to 4 conductor layers (five dielectric layers) at an overall thickness of approximately 10µm) have been fabricated. Such circuits offer significant promise in many advanced packaging applications such as: biomedical implant and monitoring devices, wearing apparel electronics, conformal antennas and receiver/ transmitter systems, and appliques of all types.
High bandwidth fast tool servo control

Fast tool servo is one of the key components in manufacturing complex surfaces with nanometer-scale resolution. This paper presents the controller design for an electromagnetically driven fast tool servo. First, the nonlinear and frequency-dependent actuator is linearized with dynamic nonlinear compensation method. Next, the plant is compensated with lead-lag controller plus integrator to achieve the cross over frequency at one twentieth of the sampling frequency. Finally, repetitive controller is plugged into the compensated loop of the last step to improve the tracking of spindle synchronized trajectory and the rejection of spindle rotation induced disturbance. Based on the integrator gain of the compensated loop, a method of tuning repetitive controller gains is presented to ensure the closed loop system phase margin in spite of changes of repetitive controller poles. Experiment is conducted on a diamond turning machine. For 100 kHz sampling frequency, the achieved closed loop bandwidth is 10 kHz with -3 dB attenuation. The maximum stroke is 50 /spl mu/m for up to 1 kHz operation and the maximum acceleration is 160 g up to 3 kHz. An aluminum part is turned with sinusoidal surface to demonstrate the usability of the control.
Genome-Wide Analysis of the Stationary-Phase Sigma Factor (Sigma-H) Regulon of Bacillus subtilis

Sigma-H is an alternative RNA polymerase sigma factor that directs the transcription of many genes that function at the transition from exponential growth to stationary phase in Bacillus subtilis. Twenty-three promoters, which drive transcription of 33 genes, are known to be recognized by sigma-H-containing RNA polymerase. To identify additional genes under the control of sigma-H on a genome-wide basis, we carried out transcriptional profiling experiments using a DNA microarray containing >99% of the annotated B. subtilis open reading frames. In addition, we used a bioinformatics-based approach aimed at the identification of promoters recognized by RNA polymerase containing sigma-H. This combination of approaches was successful in confirming most of the previously described sigma-H-controlled genes. In addition, we identified 26 putative promoters that drive expression of 54 genes not previously known to be under the direct control of sigma-H. Based on the known or inferred function of most of these genes, we conclude that, in addition to its previously known roles in sporulation and competence, sigma-H controls genes involved in many physiological processes associated with the transition to stationary phase, including cytochrome biogenesis, generation of potential nutrient sources, transport, and cell wall metabolism.
Redox-driven dissolution of clay minerals by uranium under high pressure CO2 conditions

article i nfo Geologic sequestration of supercritical CO2 is one technology proposed to mitigate global warming. Increased acidity of brine due to CO2 injection could lead to mineral dissolution of cap rock and well seals and mobilization of contaminants (e.g., U, Pb, As). In this study we examined the dissolution of nontronite NAu-2, an Fe(III)-rich clay mineral, and partially-reduced nontronite (R-NAu-2) in a synthetic brine (0.33 M Na2SO4) under high pres- sure CO2 conditions (PT =9 .66 bar, PCO2 ≥ 8.66 bar CO2 , T=2 0 °C) and in 1.40 M H3PO4-0.50 M H2SO4. Uranyl(VI) or biogenic uraninite(IV) was added as a redox-active contaminant and reaction kinetics were measured over a 15 d period. Unaltered nontronite (3.4% Fe(II)) dissolved very little under high pressure CO2 conditions. However, chemically-reduced nontronite (48% Fe(II)) dissolved more rapidly (half-life of 78.4 d under high pressure CO2 conditions, 17.8 h in H3PO4-H2SO4). Structural Fe(II) in reduced nontronite (R-NAu-2 Fe(II)) was preferentially dissolved compared to structural Fe(III) in unaltered nontronite (NAu-2 Fe(III)). No redox reactions were observed between R-NAu-2 Fe(II) and U(VI). In contrast, uraninite was oxidized by NAu-2 Fe(III) faster and to a greater extent under high pressure CO2 conditions as compared to ambient pressure conditions (PT = 1.0 bar, 95:5% N2:H2). Redox reactions between uraninite and NAu-2 Fe(III) enhanced the dissolution of both clay and U, indicative of potential risks associated with geologic carbon sequestration. © 2014 Elsevier B.V. All rights reserved.
"Physiology in the News": using press releases to enhance lay communication and introduce current physiology research to undergraduates.

many physiology laboratory courses are focused around observable phenomena in the human body, specifically those that are well known. It is commonly observed that once these laboratory exercises are established, these laboratories do not typically change from semester to semester. This style of
How is America 'Divided by God'?

Americans are fundamentally divided over the proper relation between government and religion, and that this division manifests itself in increasingly acrimonious disputes over things such as public religious symbols and the teaching of intelligent design in public schools. These differences are unlikely to be resolved by straightforward appeals to constitutional history or precedent, so as scholars we would do well to go deeper and try to understand the underlying differences in presuppositions about religion, law, and pluralism. But what are the fundamental underlying differences in presuppositions that surface in more concrete controversies over crosses and curriculum and the like? Where exactly does the fault line lie, so to speak? This essay suggests that perhaps the most illuminating answer is suggested very early on in an important recent book by Noah Feldman: Americans are "divided by God." The essay goes on to explore, while indulging in some amateur theology and armchair sociology, how basic differences about God might animate the political and legal controversies that we have been observing.
The reliability and validity of the cultural congruity and university environment scales with Chicana/o community college students

AbstractFollowing the calls for increased research on the educational experiences of Chicana/o community college students, and the development of culturally applicable measures for communities of color, this study examined the utility and the applicability of the Cultural Congruity Scale (CCS) and University Environment Scale (UES) for use with Chicana/o community college students. Applying a psychosociocultural framework, the reliability, construct, and criterion-related validity of the scales for use with a sample of 110 Chicana/o community college students was examined. Results demonstrated adequate reliability and construct validity, with indication of applicability of these scales for the study’s sample. Overall, the study challenges normative practices in educational research that students—despite their race/ethnicity, backgrounds, and histories—face similar educational experiences. Implications are discussed.
A boundary layer model for wall shear stress in arterial stenosis

This paper proposes a model for wall shear stress in arterial stenosis based on boundary layer theory. Wall shear stress estimates are obtained by solving the momentum integral equation using the method proposed by Walz and applying this method to various stenosis geometries for Reynolds numbers (Re) of Re = 59-1000. Elevated wall shear stress may be of importance when considering thrombosis and vascular erosion in stenosis, as well as the potential for debris from the stenotic area to 'break away' and cause further pathology. The values of shear stress obtained using the model in this study agree well with published values of wall shear stress. When compared to a previously published boundary layer model utilizing the Thwaites method (Reese and Thompson, 1998), the model proposed herein performs better at higher Re while the model utilizing the Thwaites method performs better at lower Re. Wall shear stresses are shown to increase with increasing stenosis (increased area reduction) for a given stenosis length, increase with increasing Re for a given stenosis geometry, and increase for steeper stenosis of the same constriction. The boundary layer model proposed can be easily implemented by clinical researchers to provide in vivo estimates of wall shear stress through arterial stenoses.
Through-thickness thermal conduction in glass fiber polymer–matrix composites and its enhancement by composite modification

Continuous glass fiber polymer–matrix composites are electrically insulating and used for printed wiring boards, but their thermal conductivity needs to be increased without sacrificing the electrical insulation ability. The through-thickness thermal conductivity of these epoxy–matrix composite laminates with in-plane fibers is found to be effectively modeled using the Rule of Mixtures with fibers and matrix mainly in parallel in the through-thickness direction, in contrast to the series model that is effective for previously studied carbon fiber composites. For the glass fiber composites, the through-thickness conductivity is similar to the in-plane conductivity. The conductivity for woven fiber composites is increased by up to 80 % by curing pressure increase (from 0.69 to 4.0 MPa), up to 50 % by solvent (toluene or ethanol) treatment of the prepreg for partial surface resin removal, and up to 90 % by boron nitride nanotube (BNNT) incorporation along with solvent treatment. The highest through-thickness thermal conductivity reached is 1.2 W/(m K), which is higher than those of all prior reports on glass fiber composites. The interlaminar interfaces are negligible in through-thickness thermal resistance compared to the laminae, as for previously studied carbon fiber composites. The fiber contribution dominates the lamina resistance. The fiber–fiber interface contribution to the lamina resistance decreases significantly with curing pressure increase or composite modification involving BNNT incorporation or solvent treatment of the prepreg.
Corticostriatal pathways contribute to the natural time course of positive mood

The natural time course of mood includes both acute responses to stimuli and spontaneous fluctuations. To date, neuroimaging studies have focused on either acute affective responses or spontaneous neural fluctuations at rest but no prior study has concurrently probed both components, or how mood disorders might modulate these processes. Here, using fMRI, we capture the acute affective and neural responses to naturalistic positive mood induction, as well as their spontaneous fluctuations during resting states. In both healthy controls and individuals with a history of depression, our manipulation acutely elevates positive mood and ventral striatum activation. Only controls, however, sustain positive mood over time, and this effect is accompanied by the emergence of a reciprocal relationship between the ventral striatum and medial prefrontal cortex during ensuing rest. Findings suggest that corticostriatal pathways contribute to the natural time course of positive mood fluctuations, while disturbances of those neural interactions may characterize mood disorder.
Abnormal Cortical Plasticity in Youth with Autism Spectrum Disorder: A Transcranial Magnetic Stimulation Case-Control Pilot Study.

Abstract Objective: This case–control study investigated the use of a low-intensity repetitive transcranial magnetic stimulation (rTMS) protocol to measure motor cortex (M1) plasticity in youth with autism spectrum disorder (ASD) compared with typically developing children (TDC). We hypothesized that impairments in long-term potentiation-like properties represent a neurophysiological biomarker of abnormal cortical function in ASD. Methods: We studied youth with ASD aged 11–18 years and matched controls (TDC). Intermittent theta burst stimulation (iTBS) was delivered to the dominant M1 at an intensity of 70% of resting motor threshold. Suprathreshold single-pulse TMS was performed to compare amplitudes of motor-evoked potentials (MEP) measured from surface electromyography electrodes on a target muscle before (20 pulses) and after (10 pulses/time point) iTBS at predefined timepoints (up to 30 minutes) to measure any potentiation effects. A linear mixed model was used to examine group differences in MEP amp...
Foraging flocks of spiders

1. The prey capture efficiency of each individual in a Cyrtophora citricola colony is dependent on time (Fig. 1), total colony size (Fig. 1), and the spider's position within the colony (Fig. 2). 2. Aggressive approaches by orbless individuals within the colony appear to concentrate on the positions within the matrix of webs that have the highest capture efficiency (compare Figs. 2 and 5). 3. The incidence of avian attempts at predation and/or cleptoparasitism increases directly with colony size (Fig. 4), which indicates that the conspicuousness of the colonies is a disadvantage to the spiders. 4. Resource division is evident in the one mixed-species aggregation observed. Sticky-orb spiders (Leucauge spp.) take the same size prey as C. citricola (Fig. 3), but forage during the day when C. citricola is least active. Tangle-web spiders (Argyrodes spp.) capture prey in significantly smaller size classes than C. citricola capture (Fig. 3).
Experimentally determined rock physics properties, MicroCT to reservoir scale.

Summary In order to monitor a CO2 injection site with seismic surveying, the dynamic rock matrix must be thoroughly understood. To assist in this understanding, we present our approach to upscaling micro-scale rock matrix properties to reservoir scale and seismic velocity ranges based on theoretical rock wave propagation models and show the richness of useful data produced by micro computed tomography (µCT). We have acquired and processed µCT images of limestone samples to gain understanding of 3-D pore orientation, pore volume distribution and pore surface area geometry at a resolution of 1.3 to 3.9 microns. By comparing µCT scans from before and after timed CO2 exposures, rock density, and pore volume changes are quantified. In an 18.5% porosity limestone sample, our analysis identifies and describes over twelve thousand pores in a 26 cubic millimeter volume at 4X zoom (3.9 micron/pixel). By observing available reactive surface area of the porosity and mass change over a series of time increments and comparing results to chemical model predictions, we refine limestone-CO2 interaction models to predict how, over time, a carbonate reservoir will change due to storage of CO2. This porosity and density change model will be applied to a larger-scale reservoir model that detects the presence of CO2 density signatures. This application will be implemented to produce theoretical seismic volumes of uncompromised future reservoirs that can be compared to repeat surveys for leak detection.
Engineering Cardiac Troponin C: Potential Therapeutic for Heart Failure

We have engineered cardiac TnCs with increased (L48Q) or decreased (D73N) Ca2+ sensitivity. To express these proteins in the in vivo heart we utilized an adeno-associated virus serotype 9 (AAV-9). The Ca2+ desensitized D73N TnC recapitulated a dilated cardiomyopathy phenotype and depressed function as observed by echocardiography and isolated cardiomyocytes. On the other hand, AAV-9 containing the Ca2+ sensitized L48Q TnC did not cause any disease phenotype or arrhythmias commonly associated with increased myofilament Ca2+ sensitivity. In healthy mice, L48Q TnC increased myocyte contraction and whole heart contractility with improved cardiovascular performance (increased V02max). Excitingly, L48Q TnC expressing mice were able to preserve higher contractility, ejection fraction, cardiac performance and decreased death rate even after undergoing trans-aortic constriction or myocardial infarction. Additionally, L48Q TnC was able to increase contractility, ejection fraction and cardiac performance in mice which expressed L48Q TnC after having a myocardial infarction. In summary, engineered TnCs show potential to be used as treatment strategies against different cardiomyopathies.