cssi/SciSciGPT-SciSciNet huggingface dataset:
A model of phasic arterial and venous blood flow in the coronary circulation

Abstract A numerical model of the coronary circulation was developed which simultaneously addresses both the arterial and venous sides of the circulation. The model is based upon the concept of an intramyocardial pump rather than the vascular waterfall mechanism and utilizes only phasic pressures as input. The left ventricular myocardium was modelled as three equal and parallel compartments, each consisting of fixed arterial and venous resistances on either side of a lumped arterial and venous intramyocardial capacitance. A time-varying intramyocardial pressure, Pi(t), different for each compartment, was applied through the capacitance. Input pressures were obtained from direct measurements of phasic aortic, right atrial and intramyocardial pressures in six open-chest anesthetized dogs. The model accurately predicted the phasic waveforms of coronary arterial inflow and venous outflow and the nearly 180° phase shift between coronary inflow and outflow. The predicted magnitudes of mean systolic coronary arterial inflow (4.7 ± 1.0 ml/min), mean diastolic coronary inflow (38.4 ± 0.5 ml/min) and mean total coronary arterial inflow (27.7 ± 1.0 ml/min) in the left anterior descending coronary artery were not significantly different from those measured in dogs. The measured values were 5.2 ± 1.0, 28.1 ± 4.2, and 22.2 ± 3.0 ml/min, respectively. The model also predicted a transmural gradient of coronary arterial blood flow which favors the subepicardial layers during systole and the subendocardial layers during diastole. The latter is consistent with experimental observations in the beating canine left ventricular myocardium.
Hemispheric differences in Polar Mesospheric Cloud morphology observed by the Student Nitric Oxide Explorer

The limb-scanning ultraviolet spectrometer on the Student Nitric Oxide Explorer (SNOE) observed Polar Mesospheric Clouds (PMCs) at 215 and 237 nm from 1998 to 2003. The altitude and brightness relative to the background atmosphere were determined for each detected cloud. In the nominal mode of operations, SNOE observed forward scattered radiance in the southern hemisphere and backward scattered radiance in the northern hemisphere. This geometry and the strong asymmetry in the Mie scattering phase function makes southern clouds appear to be much brighter in the south relative to the north. During the northern 2000 PMC season and the southern 2000/2001 season, SNOE was operated in a special mode that permitted observation of both forward and backward scattered radiance over the entire polar region throughout the season. Observing the two hemispheres in identical geometries allows for a comparison of the spatial and temporal morphology of PMCs during those two seasons that is not limited by observational differences, either in scattering angle or local time. SNOE observed more than 32,000 clouds in the Northern Hemisphere (NH) in 2000 and more than 15,800 clouds in the Southern Hemisphere (SH) in 2000/2001. This data set offers the following conclusions. There were significantly fewer PMCs observed in the south relative to the north, by nearly a factor of two, for the seasons observed. The frequency of occurrence of PMC was larger in the north with greater equatorward extent. Using a statistical description of the distribution of cloud brightness, we show that a larger population of bright clouds exist in the north relative to the south. In agreement with previous studies, we show that the northern clouds are on average 1.1 km lower in altitude than those of the south. The southern hemisphere clouds exhibit larger variability in frequency of occurrence than the northern hemisphere clouds.
Learning where to look

Knowledge of object locations in direct manipulation interfaces improves performance by restricting visual search. This paper explores the effects of label representativeness and practice on the learning of object locations. Results showed that as label representativeness decreased, location knowledge increased. All participants were shown to have learned locations to some extent, however, even those using an interface which offered little benefit to doing so, indicating that such learning is pervasive.
Proteome‐wide analysis of nonsynonymous single‐nucleotide variations in active sites of human proteins

An enzyme's active site is essential to normal protein activity such that any disruptions at this site may lead to dysfunction and disease. Nonsynonymous single-nucleotide variations (nsSNVs), which alter the amino acid sequence, are one type of disruption that can alter the active site. When this occurs, it is assumed that enzyme activity will vary because of the criticality of the site to normal protein function. We integrate nsSNV data and active site annotations from curated resources to identify all active-site-impacting nsSNVs in the human genome and search for all pathways observed to be associated with this data set to assess the likely consequences. We find that there are 934 unique nsSNVs that occur at the active sites of 559 proteins. Analysis of the nsSNV data shows an over-representation of arginine and an under-representation of cysteine, phenylalanine and tyrosine when comparing the list of nsSNV-impacted active site residues with the list of all possible proteomic active site residues, implying a potential bias for or against variation of these residues at the active site. Clustering analysis shows an abundance of hydrolases and transferases. Pathway and functional analysis shows several pathways over- or under-represented in the data set, with the most significantly affected pathways involved in carbohydrate metabolism. We provide a table of 32 variation–substrate/product pairs that can be used in targeted metabolomics experiments to assay the effects of specific variations. In addition, we report the significant prevalence of aspartic acid to histidine variation in eight proteins associated with nine diseases including glycogen storage diseases, lacrimo-auriculo-dento-digital syndrome, Parkinson's disease and several cancers.
Design and fabrication of microfluidic devices for multiphase mixing and reaction

Using silicon microfabrication technology, microchemical devices have been constructed for the purpose of conducting heterogeneously catalyzed multiphase reactions. The motivation behind the design, the fabrication approach, and the experimental characterization are presented for two classes of devices. The first design involves multiple parallel channels with integrated filter structures to incorporate standard catalytic materials. These catalysts are in the form of finely divided porous particles in a packed-bed arrangement. The second device involves the incorporation of porous silicon as a catalyst support, in the form of a thin layer covering microstructured channels. These microstructured channels simulate the structure of a packed bed and enhance mass transfer relative to an open channel. The ability to incorporate features at the tens-of-microns scale can reduce the mass-transfer limitations by promoting mixing and dispersion for the multiple phases. Directly integrating the catalyst support structures into the channels of the microreactor allows the precise definition of the bed properties, including the support's size, shape and arrangement, and the void fraction. Such a design would find broad applicability in enhancing the transport and active surface area for sensing, chemical, and biochemical conversion devices. Reaction rates for the gas-liquid-solid hydrogenation of cyclohexene using the integrated catalyst with porous silicon as a support compare favorably to those rates obtained with the packed-bed approach. In both cases, the mass transfer coefficient is at least 100 times better than conventional laboratory reactors.
Hippo in the Path to Heart Repair

The inability of the adult human heart to regenerate in response to injury, disease, and aging stands as a central challenge in cardiovascular medicine. Following myocardial infarction (MI), billions of cardiomyocytes are lost and replaced with an avascular fibrotic scar. Although various medical interventions have augmented survival rates after MI, the fibrotic myocardium mitigates cardiac contractility, leading to a poor long-term prognosis in these patients. Thus, there is an immense need for innovative approaches to repopulate lost cardiomyocytes following cardiac injury. Article, see p 354 In principle, several biological approaches to heart regeneration can be envisioned, including stem cell therapies, reprogramming of cardiac fibroblasts into cardiomyocytes, activation of cardiomyocyte proliferation, and suppression of fibrosis. However, each of these approaches faces uncertainties and challenges that have yet to be overcome. For example, although harnessing the potential of ostensible cardiac stem cells represents an attractive approach to repopulate lost cardiomyocytes, the process has proven to be, thus far, inefficient and tenuous because of the inability of stem cells to fully adopt a contractile phenotype, incomplete electrophysical integration into the myocardium, and inefficient long-term retention of transplanted cells.1–3 What is irrefutable is that the level of turnover of cardiomyocytes in adult mammals is inadequate to account for significant regeneration or functional restoration of the heart after severe injury. Another approach to replenish myocytes after injury would be to convert resident cardiac fibroblasts directly into cardiomyocytes. Recently, it has been demonstrated that fibroblasts can be converted into cardiomyocytes in vitro with the viral addition of a cocktail of cardiac transcription factors.4 In related studies, forced expression of only 3 or 4 cardiac transcription factors was shown to be sufficient to induce cardiac gene expression in cardiac fibroblasts in vivo, which enhanced cardiac function and attenuated ventricular remodeling after MI.5 …
FACE-GRAB: Face recognition with General Region Assigned to Binary operator

Face recognition in unconstrained environments is one of the most challenging problems in biometrics. One vexing problem in unconstrained environments is that of scale; a face captured at large distances is considerably harder to recognize than the same face at small distances. Several methods have been proposed to tackle unconstrained face recognition in a robust fashion, including face descriptors such as LBP and its many variations, of which some are less sensitive to scale variations than others. In this paper, we present a novel operator called General Region Assigned to Binary (GRAB), developed as a generalization of LBP. We demonstrate its performance for face recognition in both constrained and unconstrained environments and across multiple scales. Unlike prior work, the GRAB descriptor accounts for multiple scales and resolutions through the size and choice of its neighborhood and is evaluated with respect to varying scales. We show that GRAB significantly outperforms LBP in cases of reduced scale on subsets of two well-known published datasets of FERET and LFW, introducing useful subsets of these datasets for recognition system evaluation.
Isaac Abarbanel's “Stance Toward Tradition”: The Case of ' A eret zeqenim

The eminent turn-of-the-sixteenth-century theologian and exegete Isaac Abarbanel was hardly the first Jewish scholar to receive established principles and ways of thinking and a large body of classical Hebrew literature from the past. Nor was he the first to feel the Jewish past's “rich and intimidating legacy” weighing on his intellectual and literary shoulders. Indeed, it has been noted that medieval Jewish writers habitually felt compelled to justify their intellectual-literary existence, and that they often did so using an almost conventional literary genre largely designed for this purpose—the introduction.
The Effect of Personal Property Taxes on Consumer Vehicle-Purchasing Decisions: A Partitioned Price/Mental Accounting Theory Analysis:

There has been concern over the impact of vehicle personal property taxes (VPPT) on a consumer's decision to replace a vehicle. Economic models suggest that income and demographic factors have an impact on the number of vehicles owned and that the level of taxation has only a modest impact. However, lower rates for VPPT are associated with a higher percentage of new car registrations. This exploratory study uses a different methodology in analyzing the impact of VPPT on the purchasing decision. Partitioned pricing and mental accounting theories provide a framework for analysis. A questionnaire was mailed to vehicle owners in high VPPT states (HS) and low VPPT states (LS). The perceived relative importance of VPPT on the purchasing decision is examined by comparing VPPT with other factors. Perceptions of the impact of VPPT on vehicle-purchasing decisions are also analyzed. Finally, a comparison is made between the HS and LS. Results suggest that VPPT have less effect on the purchase of a replacement vehicl...
Does Mathematics Remediation Work?: A Comparative Analysis of Academic Attainment among Community College Students.

Postsecondary remediation is a controversial topic. On one hand, it fills an important and sizeable niche in higher education. On the other hand, critics argue that it wastes tax dollars, diminishes academic standards, and demoralizes faculty. Yet, despite the ongoing debate, few comprehensive, large-scale, multi-institutional evaluations of remedial programs have been published in recent memory. The study presented here constitutes a step forward in rectifying this deficit in the literature, with particular attention to testing the efficacy of remedial math programs. In this study, I use hierarchical multinomial logistic regression to analyze data that address a population of 85,894 freshmen, enrolled in 107 community colleges, for the purpose of comparing the long-term academic outcomes of students who remediate successfully (achieve college-level math skill) with those of students who achieve college-level math skill without remedial assistance. I find that these two groups of students experience comparable outcomes, which indicates that remedial math programs are highly effective at resolving skill deficiencies.
A quantitative trait locus for ascites on chromosome 9 in broiler chicken lines

A genome-wide SNP survey was used to identify chromosomal regions that showed linkage disequilibrium with respect to ascites susceptibility and ventricular hypertrophy in an F2 cross between previously described ascites-resistant and -susceptible lines. Variable number tandem repeats were used to obtain genotype data to further characterize these regions. A region on chromosome 9 (12 to 13 Mbp in 2011 assembly) shows association with ascites in the ascites lines and in several commercial broiler breeder lines with a significant sex effect. There are 2 candidate genes, AGTR1 (an angiotensin II type 1 receptor) and UTS2D (urotensin 2 domain containing), in this region that have been associated with hypertension and hypoxic response in mammals.
VIOLIN: virtual internetworking on overlay infrastructure

We propose a novel application-level virtual network architecture called VIOLIN (Virtual Internetworking on OverLay INfrastructure). VIOLINs are isolated virtual networks created on top of an overlay infrastructure (e.g., PlanetLab). Entities in a VIOLIN include virtual end-hosts, routers, and switches implemented by software and hosted by physical overlay hosts. Novel features of VIOLIN include: (1) a VIOLIN is a “virtual world” with its own IP address space. All its computation and communications are strictly con.ned within the VIOLIN. (2) VIOLIN entities can be created, deleted, or migrated on-demand. (3) Value-added network services not widely deployed in the real Internet can be provided in a VIOLIN. We have designed and implemented a prototype of VIOLIN in PlanetLab.
Existence of ${\cal H}$ -Matrix Representations of the Inverse Finite-Element Matrix of Electrodynamic Problems and ${\cal H}$ -Based Fast Direct Finite-Element Solvers

In this work, we prove that the sparse matrix resulting from a finite-element-based analysis of electrodynamic problems can be represented by an H matrix without any approximation, and the inverse of this sparse matrix has a data-sparse H-matrix approximation with error well controlled. Two proofs are developed. One is based on the general eigenvalue-based solution to the ordinary differential equations, and the other is based on the relationship between a partial differential operator and an integral operator. Both proofs have reached the same conclusion. Based on the proof, we develop an H-matrix-based direct finite-element solver of O (kN logN) memory complexity and O (k2Nlog2N) time complexity for solving electromagnetic problems, where k is a small parameter that is adaptively determined based on accuracy requirements, and N is the number of unknowns. Both inverse-based and LU-based direct solutions are developed. The LU-based solution is further accelerated by nested dissection. A comparison with the state-of-the-art direct finite element solver that employs the most advanced sparse matrix solution has shown clear advantages of the proposed direct solver. In addition, the proposed solver is applicable to arbitrarily-shaped three-dimensional structures and arbitrary inhomogeneity.
Mechanistic Studies of Palladium Thin Film Growth from Palladium(II) β-Diketonates. 1. Spectroscopic Studies of the Reactions of Bis(hexafluoroacetylacetonato)palladium(II) on Copper Surfaces

The reactions of bis(hexafluoroacetylacetonato)palladium(II), Pd(hfac) 2, on copper have been studied. Whereas multilayers of Pd(hfac)2 desorb molecularly from copper surfaces between 200 and 270 K, submonolayer coverages of Pd(hfac)2 react in a multistep sequence. At temperatures below 120 K, Pd(hfac)2 transfers its hfac ligands to the copper surface and the metal center is reduced to Pd 0 . The hfac groups adopt a variety of molecular orientations on the surface at 120 K but undergo an apparent ordering transition near 300 K that re-orients the hfac groups to an upright geometry (perpendicular to the surface plane). At low coverages on clean surfaces, further annealing results in the decomposition of the surface-bound hfac ligands to give adsorbed Pd atoms and COCF3, CF3, and fluoride species. These intermediates ultimately yield a partial monolayer of Pd atoms, a carbon (possibly graphitic) deposit, and a variety of organic products that desorb between 500 and 650 K; the desorbing flux after ionization consists of CF3COF, COCF3 ,C F 3, and CO fragments. The activation parameters for the decomposition of hfac groups on copper foils have been determined to be A ) 1.3 10 13 s -1 and Ea ) 36.8 kcal mol -1 . When Pd(hfac)2 is dosed onto copper surfaces bearing submonolayer coverages of carbon, a new reaction channel is evident: some of the hfac ligands abstract copper atoms from the surface and generate Cu(hfac)2, which desorbs when the surface is heated. The palladium atoms remain behind and diffuse into the bulk of the Cu crystal. This redox transmetalation reaction (Pd II (hfac)2 + Cu 0 f Pd 0 + Cu II (hfac)2) is the same one that is responsible for the ability of Pd(hfac)2 to effect the chemical vapor deposition of palladium selectively on copper at higher pressures. This redox transmetalation reaction is the first example of the simultaneous etching of copper and deposition of palladium.
Digital Combination of Buck and Boost Converters to Control a Positive Buck–Boost Converter and Improve the Output Transients

A highly efficient and novel control strategy for improving the transients in the output voltage of a DC-DC positive buck-boost converter, required for low-power portable electronic applications, is presented in this paper. The proposed control technique can regulate the output voltage for variable input voltage, which is higher, lower, or equal to the output voltage. There are several existing solutions to these problems, and selecting the best approach involves a tradeoff among cost, efficiency, and output noise or ripple. In the proposed method, instead of instantaneous transition from buck to boost mode, intermediate combination modes consisting of several buck modes followed by several boost modes are utilized to distribute the voltage transients. This is unique of its kind from the point of view of improving the efficiency and ripple content in the output voltage. Theoretical considerations are presented. Simulation and experimental results are shown to prove the proposed theory.
Histamine inhibits KCNQ2/KCNQ3 channel current via recombinant histamine H1 receptors

Abstract A variety of agonists are capable of inhibiting M-type K + channels via the activation of G-protein coupled receptors which converge on phospholipase-C (PLC) via the activation of G q/11 . Histamine acting via H 1 receptors also activates PLC but to date has not been shown to produce M-current (I M ) modulation. We postulated that histamine would modulate recombinant M-channels after expressing histamine H 1 receptors in heterologous systems. Expression of KCNQ2 and KCNQ3 K + channel subunits by transient transfection in HEK 293T and HeLa cells caused the induction of a slow time-dependent outward current characteristic of I M . Application of histamine (10 μM) to cells transfected with KCNQ2 and KCNQ3 K + channel subunits and H 1 histamine receptors produced a rapid and reversible inhibition. I M modulation by histamine was concentration-dependent, half maximal inhibition occurring at 399 nM with a Hill coefficient of 1.09 and was completely abolished by the H 1 receptor selective antagonist, astemizole. Studies of the modulatory effects of histamine on I M may aid in elucidating the signal transduction pathway(s) involved in I M modulation.
VOLUME VELOCITY CONTROL OF SOUND TRANSMISSION THROUGH COMPOSITE PANELS

Abstract A design method for minimizing the sound transmitted through an array of panels is presented. This method is based on minimizing the volume velocity of individual segments of the array using integrated control loudspeakers. In this manner, each of the control segments can be treated and controlled separately. The basic acoustic equations governing volume velocity control are presented and it is shown that, at low frequencies, this method achieves global sound power reductions in the far-field. Further analysis shows that this method will achieve significant sound power reductions (10 dB or more) for values ofkLof 3·0 or less, whereLis the characteristic dimension of each control segment. Tests conducted in a transmission loss chamber verify the efficacy of volume velocity control using a digital controller. The controller, based on the filtered-X control algorithm, allows for control over a frequency band and results show sound power reductions of 9 dB over a 60 Hz bandwidth. These tests are among the first attempts to use the volume velocity control method over a band of frequencies. The experimental results are complemented by numerical simulations. The results show promise that this methodology is an effective way to control broad band, low-frequency sound transmitted to enclosed spaces, such as airplane or helicopter cabins.
The Poisoning and Activation of Thoria-coated Filament Emitters

ABSTRACT This paper describes an experimental investigation of the activation and poisoning of thoria-coated iridium and tungsten filament emitters. It is shown that activation is by the formation of free thorium. Pulse emissions are derived from both the coating and core surfaces, but under d.c. conditions the coating surface is deactivated and the emission derives mainly from the core surface. Poisoning is caused by oxygen water vapour and carbon dioxide but not by hydrogen and carbon monoxide. The coated tungsten resists poisoning better than the iridium, as free thorium is formed chemically by the former but not by the latter. Taking d.c. emission from either filament produces thorium olectrolytically and this gives an increased resistance to poisoning. Some of the thorium so produced dissolves into the iridium core and subsequently increases the resistance to poisoning. The coated iridium filament can withstand exposure to the atmosphere when hot, without appreciable deterioration.
The Obesity Epidemic and the Rise and Fall of Public Health

"They don't understand how this could happen. I tell them that they have crushed their knees under their own weight."
Few Preschool Boys and Girls with ADHD are Well-Adjusted During Adolescence

To estimate the prevalence of being well-adjusted in adolescence, boys and girls with (n = 96) and without (n = 126) attention-deficit/hyperactivity disorder (ADHD) were assessed seven times in eight years starting when they were 4–6 years of age. Symptoms of ADHD, ODD/CD, and depression/anxiety in addition to social skills and social preference were gathered using multiple methods and informants. Being well-adjusted was defined by surpassing thresholds in at least four of the five domains. At the 7- and 8-year follow-up, when youth were 11–14 years old, probands were significantly less likely to be well-adjusted relative to age- and ethnicity-matched control children. Only a minority of children with ADHD was well-adjusted in adolescence when emotional, behavioral, and social domains were considered simultaneously. Even when their ADHD symptoms improved over time, most probands exhibited significant impairment 7–8 years after their initial assessment.
Lighting Transfer Functions Using Gradient Aligned Sampling

An important task in volume rendering is the visualization of boundaries between materials. This is typically accomplished using transfer functions that increase opacity based on a voxel's value and gradient. Lighting also plays a crucial role in illustrating surfaces. In this paper we present a multi-dimensional transfer function method for enhancing surfaces, not through the variation of opacity, but through the modification of surface shading. The technique uses a lighting transfer function that takes into account the distribution of values along a material boundary and features a novel interface for visualizing and specifying these transfer functions. With our method, the user is given a means of visualizing boundaries without modifying opacity, allowing opacity to be used for illustrating the thickness of homogeneous materials through the absorption of light.
Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise

The present study was designed to determine whether consumption of an oral essential amino acid-carbohydrate supplement (EAC) before exercise results in a greater anabolic response than supplementa...
Myc Induces miRNA-Mediated Apoptosis in Response to HDAC Inhibition in Hematologic Malignancies

Alterations in the expression or function of histone deacetylases (HDAC) contribute to the development and progression of hematologic malignancies. Consequently, the development and implementation of HDAC inhibitors has proven to be therapeutically beneficial, particularly for hematologic malignancies. However, the molecular mechanisms by which HDAC inhibition (HDACi) induces tumor cell death remain unresolved. Here, we investigated the effects of HDACi in Myc-driven B-cell lymphoma and five other hematopoietic malignancies. We determined that Myc-mediated transcriptional repression of the miR-15 and let-7 families in malignant cells was relieved upon HDACi, and Myc was required for their upregulation. The miR-15 and let-7 families then targeted and downregulated the antiapoptotic genes Bcl-2 and Bcl-xL, respectively, to induce HDACi-mediated apoptosis. Notably, Myc also transcriptionally upregulated these miRNA in untransformed cells, indicating that this Myc-induced miRNA-mediated apoptotic pathway is suppressed in malignant cells, but becomes reactivated upon HDACi. Taken together, our results reveal a previously unknown mechanism by which Myc induces apoptosis independent of the p53 pathway and as a response to HDACi in malignant hematopoietic cells.
Designing a New System for Sharing Computer Science Teaching Resources

Many online communities for high school computer science teachers have been developed to help teachers connect with each other and share course materials. However, these sites have failed to meet teachers' needs and are widely underused. Creating new communities by repeat-ing the design of existing sites will only require teachers to search additional sites to find what they need. Prior work has framed the inefficacy of these sites in terms of usabil-ity without exploring additional underlying problems that discourage teachers from using the sites. We interviewed teachers about their attitudes toward existing sites to further our understanding of these underlying problems. During interviews teachers said that finding relevant resources is difficult and contributing to these communities requires too much time. We propose a new design for a system that low-ers the barrier to participation while providing teachers with improved access to each other's relevant course materials.
Serological specificity of type E botulinal toxin.

SummaryA purified preparation of type E botulinal toxin possessed serological properties distinct from those of crude preparations. In vitro studies suggested that the specific toxicity of a toxin is not necessarily a true reflection of its relative concentration, and that some type E botulinal toxin molecules exist in a nontoxic or less toxic form than others. Although specific toxicities may be misleading in predicting the relative in vitro behavior of E toxins, it would be expected that purified Sakaguchi toxin would be a better inhibitor in HI than partially purified toxins on a weight basis with purified Sakaguchi SRBC antigen. The purified Sakaguchi toxin appears to be suitable for in vitro investigations and immunoassays.
Susceptibility to Infection as Influenced by Acclimatization to Altitude and Krebs Cycle Inhibitors and Intermediates

Exposure of mice to simulated high altitude of about 20,000 feet for a period of 3 weeks renders them more susceptible than normal control mice to artificially induced infections with Salmonella typhimurium.1 No experimentally detectable differences in either the cellular or the humoral defense mechanisms, however, could be found to accompany adaptation to altitude. It was postulated that the greater susceptibility of such mice was due to an undetected and unspecified type of alteration in metabolism. In order to test the validity of the suggestion that host metabolism modifies response to infection, the survival time of normal mice infected with S. typhimurium was compared to that of mice similarly infected and then given a series of injections of compounds known to inhibit certain steps in the tricarboxylic acid cycle.2,3 Intermediates of the cycle also were employed.
Sensitivity to dietary phosphorus limitation in native vs. invasive lineages of a New Zealand freshwater snail.

Why some species and lineages are more likely to be invasive than others is one of the most important unanswered questions in basic and applied biology. In particular, the relative contributions to the invasion process of factors like pre-adaptation to invasiveness in the native range, evolution post-colonization, and random vs. non-random sampling of colonist lineages remain unclear. We use a powerful common garden approach to address the potential for a role for sensitivity to nutrient limitation in determining the invasiveness of particular lineages of Potamopyrgus antipodarum, a New Zealand freshwater snail that has become globally invasive. We quantified specific growth rate (SGR), an important fitness-related trait in this species, under high phosphorus (P) vs. low-P conditions for a diverse set of native and invasive P. antipodarum. This experiment revealed that native-range P. antipodarum experience a more severe decline in SGR in low-P conditions relative to SGR in high-P conditions than their invasive range counterparts. Although these results suggest resilience to P limitation in invasive lineages, the absence of significant absolute differences in SGR between native and invasive lineages indicates that a straightforward connection between response to P limitation and invasiveness in P. antipodarum is unlikely. Regardless, our data demonstrate that invasive vs. native lineages of P. antipodarum exhibit consistently different responses to an important environmental variable that is rarely studied in the context of invasion success. Further studies directed at exploring and disentangling the roles of sampling effects, selection on preexisting variation, and evolution after colonization will be required to provide a comprehensive picture of the role (or lack thereof) of nutrient limitation in the global invasion of P. antipodarum, as well for as other invasive taxa.
Hemodynamics of graded water immersion in the baboon: +Gz protection potential.

INTRODUCTION Fluid-filled anti-G suits depend on external fluid counterpressure to maintain near-normal hemodynamics during +Gz (head-to-foot inertial force). However, the relationship between external fluid level, hemodynamic events, and +Gz tolerance has not been determined. METHODS Seven anesthetized male baboons (avg. wt. = 27.2 kg) were catheterized for measurement of left ventricular pressure (LVP), right ventricular pressure (RVP), aortic BP (ABP), central venous pressure (CVP), pulmonary artery pressure, cardiac output, and esophageal pressure. The animals were seated in a restraint chair and control data were collected, followed by six discrete steps of water immersion (WI): 1) knee; 2) hip; 3) xiphoid; 4) mid-chest; 5) neck; and 6) return to the xiphoid (data check). Each level was maintained until hemodynamic stabilization. Rectal temperature averaged 33.5 degrees C; water bath temperature was maintained at 34 degrees C. RESULTS There was a significant (p < 0.05) increase in most hemodynamic parameters with WI to the xiphoid, mid-chest, and neck. With WI to the neck, CVP, LV, and RV end diastolic pressures increased by 8.7 mmHg, 19.6 mmHg, and 8.0 mmHg, respectively, suggesting a major passive increase in thoracic and cardiac blood volume, whereas mean ABP (MABP) increased by 18.6 mmHg and total peripheral resistance significantly decreased. Heart rate did not change significantly. CONCLUSION The increase in MABP with WI to the neck would provide slightly more than +1 Gz relaxed protection. Additional +Gz would require pressure breathing to overcome the increased external hydrostatic pressure on the thorax. Water-filled anti-G suits filled to the xiphoid cannot provide adequate relaxed +Gz protection for current high performance aircraft without supplemental factors such as additional pressure in the suit or positive pressure breathing.
Barrier, mechanical, and thermal properties of the three-layered co-extruded blown polyethylene/ethylene–vinyl alcohol/low density polyethylene film without tie layers

This article investigates three-layer co-extruded blown film comprised of low-density polyethylene (LDPE)/ethylene–vinyl alcohol (EVOH)/LDPE without adhesion layers. Various thicknesses of pure EVO...
SNN: Stacked Neural Networks.

It has been proven that transfer learning provides an easy way to achieve state-of-the-art accuracies on several vision tasks by training a simple classifier on top of features obtained from pre-trained neural networks. The goal of this work is to generate better features for transfer learning from multiple publicly available pre-trained neural networks. To this end, we propose a novel architecture called Stacked Neural Networks which leverages the fast training time of transfer learning while simultaneously being much more accurate. We show that using a stacked NN architecture can result in up to 8% improvements in accuracy over state-of-the-art techniques using only one pre-trained network for transfer learning. A second aim of this work is to make network fine- tuning retain the generalizability of the base network to unseen tasks. To this end, we propose a new technique called "joint fine-tuning" that is able to give accuracies comparable to finetuning the same network individually over two datasets. We also show that a jointly finetuned network generalizes better to unseen tasks when compared to a network finetuned over a single task.
Effects of freezing to −196 °C and thawing on Setaria lutescens seeds

The effects of single and repeated freezing and thawing of Setaria lutescens seeds in liquid nitrogen were investigated. One freeze to −196 °C followed by a slow thaw, increased seed germination from 40 to 70%, but additional freeze-thaw cycles reduced germination to 30%. Using a scanning electron microscope, evidence was produced that seed coat cracking did not cause either initial increased, or subsequent reduced germination. Observations with a transmission electron microscope revealed that disruption of the integrity of lipid bodies accompanied increased damage from repeated freezing at −196 °C and thawing. Repeated freezing and thawing of seeds stored in liquid nitrogen should be done with care to avoid loss of the germplasm.
Radar Detection of Low-Level Wind Shear

Another chapter of my life after NASA concerns the invention and patent on a method of using the conventional airport surveillance radar (ASR-9) to detect hazardous low-level wind shear (131). Prior to mid-1988, wind shear had been responsible for twelve major aircraft accidents, seven of which resulted in the loss of 575 lives. Thus, wind shear detection and warning was high on the FAA’s priority list of critical problems. Westinghouse Electric, the company responsible for the development of the ASR-9, called me in to discuss the possibility of upgrading the radar to include a wind shear detection capability. I was impressed with the list of distinguished company radar experts at our first meeting on September 19, 1985. But it soon became clear that they had not the slightest idea of how one might approach the problem. Neither did I at that point. The essential obstacle was the fact that the antenna radiated two wide vertical fan beams, one tilted slightly above the other. These beams would therefore detect all the precipitation over a broad altitude range, whereas it was necessary to measure only the Doppler velocities and wind shear at the lower levels where the aircraft were flying during takeoff and landing. After several hours of discussion, none of us had any concept of how to proceed. Nevertheless, I agreed to think about the problem and get back to them later to sign a consulting agreement.
LUCA and the Tree of Life

Abstract Taxonomy seeks to classify organisms according to their similarities and differences. Phylogeny seeks to reconstruct their evolutionary relationships: which species are more related to each other than to others, how related they are, and when their divergence happened in their evolutionary history. Similarities due to descent from common ancestors are said to be homologous . But similarities may also arise by functional convergence ; these are called analogous . Anagenesis refers to the process of evolutionary change through time; cladogenesis refers to the process of diversification of species . The main relationships in the evolutionary history of all organisms, from the very beginning of life to the present organisms, are reconstructed using diverse sources of evidence, including notably molecular biology.
Analysis of tug-barge connection force measurements

This paper summarizes the analysis of four integrated tug-barge (ITB) model tests in calm water and waves. The results show the relationship of the tug-barge connection forces to wavelength and heading, and indicate that the maximum longitudinal, transverse, and vertical connection forces occur at wave encounter angles of 0, 45, 225, and 0 deg, respectively. Additionally, the results of a simplified linear analysis are used to evaluate the possibility of obtaining connection force predictions based on force vector analysis and the relationship of connection force to block coefficient.
The Technology: Has the Digital Communication Technology Changed the Way Markets Function? Cooperation or Competition?

As social beings, humans have traded goods and services for generations. The mechanics of exchange have adapted over time to the changing environment but the underlying incentives remain the same. Differences in preferences and resources are bridged by connecting with individuals in other parts of the economic network using digital communication technology (DCT). DCT has generated new scarcities and new mechanisms for resource allocation, enlarging the scope of exchange along three dimensions. One is the trend toward organizational restructuring (OR) precipitated by granularity and disintermediation. The second trend is the emergence of organizational behemoths (OB), fostered by network effects. And third, competition for scarce resources is channeled into cooperation as individuals adapt to a rapidly changing context for exchange, and this adaptation itself changes the environment.
Making the most of the adolescent male health visit Part 2: The physical exam

Is the young man's height and weight normal for his developmental stage? What about his pubertal development? The comprehensive physical should answer these and other questions—opening the door to further investigation when needed.
Hot flush frequency and severity at baseline as predictors of time to transient and stable treatment success: pooled analysis of two CE/BZA studies

AbstractObjective:To evaluate the impact of baseline hot flush frequency and severity on time to symptom improvement during treatment with conjugated estrogens/bazedoxifene (CE/BZA).Methods:Data were pooled through week 12 from two randomized placebo-controlled trials (SMART-1 and SMART-2) of nonhys
Feedback design for multi-contact push recovery via LMI approximation of the Piecewise-Affine Quadratic Regulator

To recover from large perturbations, a legged robot must make and break contact with its environment at various locations. These contact switches make it natural to model the robot as a hybrid system. If we apply Model Predictive Control to the feedback design of this hybrid system, the on/off behavior of contacts can be directly encoded using binary variables in a Mixed Integer Programming problem, which scales badly with the number of time steps and is too slow for online computation. We propose novel techniques for the design of stabilizing controllers for such hybrid systems. We approximate the dynamics of the system as a discrete-time Piecewise Affine (PWA) system, and compute the state feedback controllers across the hybrid modes offline via Lyapunov theory. The Lyapunov stability conditions are translated into Linear Matrix Inequalities. A Piecewise Quadratic Lyapunov function together with a Piecewise Linear (PL) feedback controller can be obtained by Semidefinite Programming (SDP). We show that we can embed a quadratic objective in the SDP, designing a controller approximating the Piecewise-Affine Quadratic Regulator. Moreover, we observe that our formulation restricted to the linear system case appears to always produce exactly the unique stabilizing solution to the Discrete Algebraic Riccati Equation. In addition, we extend the search from the PL controller to the PWA controller via Bilinear Matrix Inequalities. Finally, we demonstrate and evaluate our methods on a few PWA systems, including a simplified humanoid robot model.
A Neuroevolutionary Approach to Adaptive Multi-agent Teams

A multi-agent architecture called the Adaptive Team of Agents (ATA) is introduced, wherein homogeneous agents adopt specific roles in a team dynamically in order to address all the sub-tasks necessary to meet the team’s goals. Artificial neural networks are then trained by neuroevolution to produce an example of such a team, trained to solve the problem posed by a simple strategy game. The evolutionary algorithm is found to induce the necessary in situ adaptivity of behavior into the agents, even when controlled by stateless feed-forward networks.
Effects of aging on temporal predictive mechanisms of speech and hand motor reaction time

Evidence from previous studies has suggested that movement execution in younger adults is accelerated in response to temporally predictable vs. unpredictable sensory stimuli. This effect indicates that external temporal information can modulate motor behavior; however, how aging can influence temporal predictive mechanisms in motor system has yet to be understood. The objective of the present study was to investigate aging effects on the initiation and inhibition of speech and hand movement reaction times in response to temporally predictable and unpredictable sensory stimuli. Fifteen younger (mean age 22.6) and fifteen older (mean age 63.8) adults performed a randomized speech vowel vocalization or button press initiation and inhibition tasks in two counterbalanced blocks in response to temporally predictable and unpredictable visual cue stimuli. Results showed that motor reaction time was accelerated in both younger and older adults for predictable vs. unpredictable stimuli during initiation and inhibition of speech and hand movement. However, older adults were significantly slower than younger adults in motor execution of speech and hand movement when stimulus timing was unpredictable. Moreover, we found that overall, motor inhibition of speech and hand was executed faster than their initiation. Our findings suggest that older adults can compensate age-related decline in motor reaction times by incorporating external temporal information and execute faster movement in response to predictable stimuli, whereas unpredictable temporal information cannot counteract aging effects efficiently and lead to less accurate motor timing predictive codes for speech production and hand movement.
Preventing bad memories: is it ethical?

The ability to eliminate traumatic memories pharmacologically poses ethical concerns. Virtual Mentor is a monthly bioethics journal published by the American Medical Association.
Urine Supersaturation: the Nucleation, Growth and Dissolution of Stones

It is generally accepted that the formation of stones in the urinary tract involves 4 basic steps: (a) the achievement of solution supersaturation with respect to the mineralizing phase, (b) the formation of stable nidi or nuclei, (c) the development of macrocrystals through crystal growth, aggregation or agglomeration and, (d) the opposing process of dissolution. Elucidation of the controlling mechanisms offers a considerable challenge since the process may result from the failure of natural inhibitors which, in normal subjects, prevent the formation of crystalluria. It is the purpose of this paper to discuss the important factors involved in these processes in relation to an understanding of the mechanisms of stone formation.
Instructors' Teaching Performance and Students' Grade Expectations: An Application of the Stochastic Frontier Model

Student evaluation of teaching (SET) scores have been used widely to assess instructors' performance in teaching, and it has been argued that instructors may "purchase" better evaluation scores by inflating students' grade expectations. In this paper, using a stochastic frontier model, we explicitly control for the grade expectation not only as a regressor but also as a factor in instructors' inefficiency in reaching the frontier. This method permits a separation of unobserved factors that are distributed randomly ("luck") from an instructor's unobservable inherent teaching skill (efficiency or lack thereof). After controlling for various instructor, student and course characteristics we find that, with students' higher grade expectations, instructors earn higher SET scores and instructors' inefficiencies decrease.