cssi/SciSciGPT-SciSciNet huggingface dataset:
Spatial Visualization and Gender Differences in High School Geometry.

The balance between visual-spatial and verbal-logical thought may determine "mathematical casts of mind" that influence how an individual processes mathematical information. Thus, to investigate the role that spatial thinking plays in learning, problem solving, and gender differences in high school geometry, spatial thought was examined along with its counterpart verbal-logical thought. The results suggest that whereas males and females differed in spatial visualization and in their performance in high school geometry, they did not differ in logical reasoning ability or in their use of geometric problem-solving strategies. There was evidence of gender differences in profiles of those mental abilities that are important for geometry performance and of a teacher-by-gender interaction on geometry achievement.
Philosophical foundations for the hierarchy of life

We review Evolution and the Levels of Selection by Samir Okasha. This important book provides a cohesive philosophical framework for understanding levels-of-selections problems in biology. Concerning evolutionary transitions, Okasha proposes that three stages characterize the shift from a lower level of selection to a higher one. We discuss the application of Okasha’s three-stage concept to the evolutionary transition from unicellularity to multicellularity in the volvocine green algae. Okasha’s concepts are a provocative step towards a more general understanding of the major evolutionary transitions; however, the application of certain ideas to the volvocine model system is not straightforward.
CADDISWORMS (TRICHOPTERA) AS IDEAL INDICATOR ORGANISMS FOR RESPIRATIONAL STUDIES OF SMALL ANIMALS

For a number of years, a line has been drawn between animals which merely live in water but obtain atmospheric air for respiration, and those truly aquatic forms which depend upon oxygen removed from solution in the water surrounding them. In making a study of the latter type of organisms, we recently noted that there are two distinct methods of respiration correlated with rate of blood circulation.
Predicting hydration free energies using all-atom molecular dynamics simulations and multiple starting conformations

Molecular dynamics simulations in explicit solvent were applied to predict the hydration free energies for 23 small organic molecules in blind SAMPL2 test. We found good agreement with experimental results, with an RMS error of 2.82 kcal/mol over the whole set and 1.86 kcal/mol over all the molecules except several hydroxyl-rich compounds where we find evidence for a systematic error in the force field. We tested two different solvent models, TIP3P and TIP4P-Ew, and obtained very similar hydration free energies for these two models; the RMS difference was 0.64 kcal/mol. We found that preferred conformation of the carboxylic acids in water differs from that in vacuum. Surprisingly, this conformational change is not adequately sampled on simulation timescales, so we apply an umbrella sampling technique to include free energies associated with the conformational change. Overall, the results of this test reveal that the force field parameters for some groups of molecules (such as hydroxyl-rich compounds) still need to be improved, but for most compounds, accuracy was consistent with that seen in our previous tests.
How regulated protein translocation can produce switch-like responses.

Abstract It is widely appreciated that the regulated translocation of signaling proteins can increase the specificity and speed of signal transduction. It is less obvious that regulated translocation can also, in principle, turn a graded response into a more switch-like one. For example, if two or more signaling proteins are induced to translocate, the result can be a switch-like, ultrasensitive response. A switch-like response will also occur if translocation raises the local concentration of a signaling protein sufficiently to partially saturate the enzyme that inactivates it. These mechanisms are likely to make the mitotic activation of CDC2 (which is accompanied by the nuclear translocation of both CDC2–cyclin-B1 and its activator, CDC25C) and the growth-factor-induced activation of MAP kinase (which, upon sustained activation, concentrates in the nucleus and might thereby partially saturate the relevant MAP-kinase phosphatases) more switch-like.
Foreign Involvement in the Preconditions for Political Violence: The World System and The Case of Chile

Current theories of internal political violence and revolution view foreign influence on these events as most often coming in two general forms: (1) direct and intentional involvement through vario...
Preparation of Silver Nanoparticles via Reduction of a Highly CO2-Soluble Hydrocarbon-Based Metal Precursor

Silver bis(3,5,5-trimethyl-l-hexyl) sulfosuccinate, Ag-AOT-TMH, exhibits 1.2 wt % solubility in dense CO 2 at 40 °C and 52 MPa. This is a remarkably high CO 2 solubility value for a nonfluorous organometallic compound. Silver nanoparticles were produced by reducing the supercritical CO 2 solution containing 0.06 wt % Ag-AOT-TMH and 0.5 wt % perfluorooctanethiol (stabilizing ligand) using a reducing agent of NaBH 4 . Silver nanoparticles ranging in size from 1 to 6 nm were characterized by transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). Although silver nanoparticles have been previously formed by a similar technique using silver acetylacetonate, that precursor is far less CO 2 -philic, exhibiting a CO 2 solubility of «0.01 wt % at 40 °C and 70 MPa. Attempts to produce silver nanoparticles from Ag-AOT-TMH in a completely nonfluorous system were unsuccessful because stabilization could not be attained with silicone-, PEG-, or hydrocarbon-based thiols; only the fluorinated thiols provided nanoparticle dispersion.
Delaying transition in Taylor-Couette flow with axial motion of the inner cylinder

Periodic axial motion of the inner cylinder in Taylor–Couette flow is used to delay transition to Taylor vortices. The outer cylinder is fixed. The marginal stability diagram of Taylor–Couette flow with simultaneous periodic axial motion of the inner cylinder is determined using flow visualization. For the range of parameters studied, the degree of enhanced stability is found to be greater than that predicted by Hu & Kelly (1995), and differences in the scaling with axial Reynolds number are found. The discrepancies are attributed to essential differences between the base flow in the open system considered by Hu & Kelly, where mass is conserved over one period of oscillation, and the base flow in the enclosed experimental apparatus, where mass is conserved at all sections at all times.
A collaborative approach to software engineering

There are computer-aided software engineering (CASE) tools that provide basic collaborative capabilities. However, CASE tools' collaborative abilities are typically very basic and are not enough for true collaborative work. This paper presents a groupware tool under development at Auburn University whose purpose is to aid in the engineering design process by allowing users to collaborate on the actual design and generate appropriate documents.
Acrocallosal syndrome: new findings.

We describe a 21-month-old girl with typical manifestations of the acrocallosal syndrome of craniofacial anomalies, agenesis of the corpus callosum, hallucal duplication, severe hypotonia, and psychomotor retardation. Our patient also had the Dandy-Walker malformation, imperforate anus with recto vaginal fistula, hypothalamic dysfunction with hypothyroidism and diabetes insipidus, thick, dysplastic pulmonic valve leaflets, central and obstructive apnea, and pulmonary hypertension. These findings add to the delineation of this syndrome.
Reduction products of 2-pyridylmethylene-1-indanones. Indanols and indenoindolizines

Several 2-pyridylmethylene-1-indanones (I) were prepared and reduced to 2-pyridyl-methyl-1-indanones (II). The reductive cyclization of 5, 6-dimethoxy- and 6-hydroxy-5-methoxy-2-pyridylmethylene-1-indanone gave the corresponding 5a, 6, 6a, 7, 8, 9, 10, 11a-octahydroindeno[2, 1-b]indolizines (X).
Robustness of the ANOVA and Tukey-Kramer statistical tests

Abstract Analysis of variance (ANOVA) allows one to compare the means of μ1, μ2,…,μm of m populations. For a randomized block single-factor design of experiments with m treatments, the analyst uses ANOVA to test the null hypothesis H0 : {μ1 = μ2 = … = μm}. If H0 is rejected, the Tukey-Kramer procedure may be used to determine which pairs of means have statistically significant differences. Unfortunately, ANOVA and the Tukey-Kramer procedures both depend upon the use of data from normal populations. Departure from normality may cause errors. These errors cannot be determined analytically; however, they can be estimated via simulation. This paper reports on the use of computer simulation to estimate the errors that attend the use of ANOVA with Tukey-Kramer to test for differences of population means.
High-Brightness and Low-Voltage Light-Emitting Devices Based on Trischelated Ruthenium(II) and Tris(2,2‘-bipyridine)osmium(II) Emitter Layers and Low Melting Point Alloy Cathode Contacts

Solid-state light-emitting devices (LEDs) were fabricated based on an amorphous film of Ru(bpy)3(ClO4)2 (bpy = 2,2‘-bipyridine) about 100 nm thick on indium−tin oxide (ITO) with printed low melting point alloys, such as Ga:In, Ga:Sn, and Bi:In:Pb:Sn, as cathodic contacts. A device with the structure of ITO (≤10 Ω/square)/Ru(bpy)3(ClO4)2/Ga:Sn produces a bright red emission (3500 cd/m2 at 4.0 V) centered at 660 nm. This new method of making contacts significantly simplifies the fabrication of an electroluminescence cell and has potential application in the production of LEDs by inkjet or microcontact printing. LEDs based on C12−Ru(bpy)3(ClO4)2, Ru(phenanthroline)3(ClO4)2, and Os(bpy)3(PF6)2 were also studied. Low melting point alloy contacts were also used with cells based on tris(8-hydroxyquinoline)aluminum.
Transforming Growth Factor-β1 Induces an Epithelial-to-Mesenchymal Transition State in Mouse Hepatocytes in Vitro

Liver fibrosis is a progressive pathologic process that involves deposition of excess extracellular matrix leading to distorted architecture and culminating in cirrhosis. The role of transforming growth factor-beta (TGF-beta) as a key molecule in the development and progression of hepatic fibrosis via the activation of hepatic stellate cells, among other fibroblast populations, is without controversy. We hereby show that TGF-beta1 induces an epithelial-to-mesenchymal transition (EMT) state in mature hepatocytes in vitro. EMT state was marked by significant upregulation of alpha(1)(I) collagen mRNA expression and type I collagen deposition. Similar changes were found in a "normal" mouse hepatocyte cell line (AML12), thus confirming that hepatocytes are capable of EMT changes and type I collagen synthesis. We also show that in hepatocytes in the EMT state, TGF-beta1 induces the snail-1 transcription factor and activates the Smad2/3 pathway. Evidence for a central role of the TGF-beta1/Smad pathway is further supported by the inhibition of EMT by Smad4 silencing using small interference RNA technology. In conclusion, TGF-beta1, a known pro-apoptotic cytokine in mature hepatocytes, is capable of mediating phenotypic changes and plasticity in the form of EMT, resulting in collagen deposition. Our findings support a potentially crucial role for EMT in the development and progression of hepatic fibrogenesis.
Multianalyte microphysiometry as a tool in metabolomics and systems biology

The determination of temporal fluxes of cellular metabolic analytes promises to revolutionize the study of metabolomics and systems biology. A review of our work on the multianalyte microphysiometer (MMP), an instrument capable of measuring extracellular changes in the flux rates of oxygen, glucose, lactate, and acid, is presented as a useful tool in extracting cellular metabolic information. Applications are reviewed in three areas: biodefense agent discrimination by monitoring changes in metabolic fluxes in response to ricin, botulinum and cholera toxins, as well as anthrax protective antigen (PA); cancer cell studies in relation to hypoxia and cell proliferation; and the short term effects of environmental agents on cell populations. Future directions include the incorporation of additional electrodes, improvements in temporal and spatial metabolic flux analysis, and miniaturization of the cell chamber and sensor technology for more cost effective and high-throughput applications in drug screening and discovery.
Development of Near-Isogenic Peanut Lines with and without Resistance to the Peanut Root-Knot Nematode

Peanut (Arachis hypogaea L.) cultivars are available that have high resistance to the peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood race 1] or tomato spotted wilt, caused by tomato spotted wilt Tospovirus (TSWV); however, no cultivars exist that have resistance to both pathogens. The objective of this research was to combine resistance to both pathogens in a single genotype. During the course of this research, we also had the opportunity to develop near-isogenic lines with and without nematode resistance. Such near-isogenic lines can be valuable research tools to obtain a better understanding of the interaction of nematodes with other pathogens of peanut. Breeding populations were developed by hybridizing the TSWV-resistant cultivar C-99R with the nematode-resistant cultivar COAN. Selection for nematode resistance was conducted using standard greenhouse screening techniques. Selection for TSWV resistance was conducted in the field with natural virus infection. A breeding line (C724-19-15) was selected that had high resistance to both pathogens. A near-isogenic line (C724-19-25) susceptible to the peanut root-knot nematode was also developed. Both breeding lines exhibited higher resistance to TSWV and higher yield than standard check cultivars when grown in fields with little or no nematode pressure.
Is there more than one way to attract a pollen tube

ZmEA1 (Zea mays egg apparatus 1) is expressed only in the egg and synergid cells. Embryo sacs with presumed reduced expression of ZmEA1 fail to attract pollen tubes. Together with data from Arabidopsis mutants and from elegant laser ablation experiments in Torenia fournieri, these results indicate that embryo sacs send signals to the incoming pollen tubes. We need to decipher how such signals are perceived and determine if the signals are species-specific.
Transfer functions for amplitude-modulated signals

THE purpose of this paper is to derive the general theoretical requirements which must be met by linear networks which are to perform specified operations on amplitude modulated signals. In particular, an exact correspondence will be established between a realizable transfer function A (s) which performs a given operation on any modulating function fm(t) and the network which performs an identical operation on the envelope of the modulated function fm(t) sin ?0 t where ?0/2 ? is the carrier frequency.
Instantaneous communication throughputs of vehicular ad hoc networks

Vehicular ad hoc networks (VANETs) formed by connected vehicles in a traffic stream could be applied to improve safety, mobility, and environmental impacts of a transportation system. In this paper, we present analytical models for the instantaneous communication throughputs of VANETs to measure the efficiency of information propagation under various traffic conditions at a time instant. In particular, we define broadcast and unicast communication throughputs by the wireless channel bandwith multiplied by the average probabilities that one vehicle is a successful receiver and sender in a VAENT, respectively. With a protocol communication model, we derive formulas to determine the probabilities for an equipped vehicle to be a successful broadcast receiver and a successful unicast receiver/sender, and obtain broadcast and unicast throughputs along discrete and continuous traffic streams. We further examine the impacts on communication throughputs of the transmission range and the interference range of dedicated short range communication devices as well as the market penetration rate of equipped vehicles and the percentage of senders. Finally, we investigate the influence of shock waves on communication throughputs.
Notes on Two Archaeological Discoveries in Northern Alaska, 1950

Several significant pre-Eskimo finds related to early aboriginal occupations in North America were made north of the Arctic Circle during the 1950 season in Alaska. These discoveries were made within and just bordering the northern side of the Brooks Range mountain province. Two of the more important finds were made by Milton C. Lachenbruch and Robert J. Hackman of the U.S. Geological Survey. Another important find was made by Irving, a student at the University of Alaska (Giddings, 1950, p. 20). Lachenbruch's and Hackman's specimens were submitted to the writer for study and are described summarily in this paper. It is reported that Irving found lithic cultural remains similar to those found by Hackman not far from the latter's station near Anaktuvuk Pass.
Improved assay for NADH dehydrogenase of the respiratory chain.

Abstract The ferricyande assay for Type I NADH dehydrogenase (high molecular weight soluble form) was evaluated. A turnover number of 4.2 × 10 5 min −1 , based on V max (ferricyanide) and FMN content, and K m (ferricyanide) of 2.2 mM were determined for this enzyme. Inclusion of a NAD-recycling system consisting of alcohol dehydrogenase and ethanol is suggested for determination of K m (NADH). This K m was found to be 17 μ M in contrast to earlier reported values of around 100 μ M.
Gravity and Newton’s Substance Counting Problem

Abstract A striking feature of Newton’s thought is the very broad reach of his empiricism, potentially extending even to immaterial substances, including God, minds, and should one exist, a non-perceiving immaterial medium. Yet Newton is also drawn to certain metaphysical principles—most notably the principle that matter cannot act where it is not—and this second, rationalist feature of his thought is most pronounced in his struggle to discover ‘gravity’s cause’. The causal problem remains vexing, for he neither invokes primary causation, nor accepts action at a distance by locating active powers in matter. To the extent that he is drawn to metaphysical principles, then, the causal problem is that of discovering some non-perceiving immaterial medium. Yet Newton’s thought has a third striking feature, one with roots in the other two: he allows that substances of different kinds might simultaneously occupy the very same region of space. I elicit the implications of these three features. For Newton to insist upon all three would transform the causal question about gravity into an insoluble problem about apportioning active powers. More seriously, it would undermine his means of individuating substances, provoking what I call ‘Newton’s Substance Counting Problem’.
A New Species for a Bromeliad Phytotelm-Dwelling Tanytarsus (Diptera: Chironomidae)

The first species of Tanytarsus Kieffer (Diptera: Chironomidae: Tanytarsini) from a phytotelm (plant-held water) is described as a larva, pupa, and adults from specimens reared from leaf axils of Guzmania (Bromeliaceae), a bromeliad from Puerto Rico. Unreared larval records from Tillandsia bromeliads from Florida seem to belong to the new species. The diversity of Chironomidae from phytotelmata is reviewed, and the existence of a further species of Monopelopia Kieffer (Tanypodinae) is reported.
Statistical radar estimate of the lunar surface roughness.

Abstract The spatial height distance autocovariance function for the central portion of the visible side of the lunar surface can be approximated by the cosine transform of the lunar return power delay spectrum, and is shown to have an exponential rather than the commonly assumed gaussian form. As many commonly occurring rough terrains also have an exponential autocovariance, it is therefore stated that the lunar surface features are in this sense similar to those of the earth. The experimental lunar echo return is then fitted to the theoretical radar scattering cross section per unit area calculated using exponential autocovariance function, exp (-|r|/B). This is shown to result in one possible set of statistical constants B/L and s/L of 1.0 and 0.1, respectively, for 56 per cent of the central lunar area where s is the standard deviation of heights and L is the wavelength used. The result is statistically interpreted to indicate that the standard deviation, and the average size (along the surface) of the lunar surface irregularities (small scale) may be of the order of 6.82 centimeters, whereas its average slope may be of the order of one in ten, which compares favorably well with the results of the acoustic simulation of moon echoes, and with other results reported so far.
Acquired left ventricular to right atrial intracardiac shunt after myocardial infarction: A case report and review of the literature

Abstract A patient without a history of heart disease was seen in our institution after a 3-week history of progressive weakness, dyspnea, and orthopnea. Transthoracic echocardiography demonstrated inferoposterobasal akinesis and a left ventricular to right atrial shunt through the coronary sinus, which was confirmed on cardiac catheterization. This is only the second case reported in the English-language literature documenting this rare shunt after a myocardial infarction.
Characteristics of production database workloads and the TPC benchmarks

There has been very little empirical analysis of any real production database workloads. Although the Transaction Processing Performance Council benchmarks C (TPC-CTM) and D (TPC-DTM) have become the standard benchmarks for on-line transaction processing and decision support systems, respectively, there has not been any major effort to systematically analyze their workload characteristics, especially in relation to those of real production database workloads. In this paper, we examine the characteristics of the production database workloads of ten of the world's largest corporations, and we also compare them to TPC-C and TPC-D. We find that the production workloads exhibit a wide range of behavior. In general, the two TPC benchmarks complement one another in reflecting the characteristics of the production workloads, but some aspects of real workloads are still not represented by either of the benchmarks. Specifically, our analysis suggests that the TPC benchmarks tend to exercise the following aspects of the system differently than the production workloads: concurrency control mechanism, workload-adaptive techniques, scheduling and resource allocation policies, and I/O optimizations for temporary and index files. We also reexamine Amdahl's rule of thumb for a typical data processing system and discover that both the TPC benchmarks and the production workloads generate on the order of 0.5 to 1.0 bit of logical I/O per instruction, surprisingly close to the much earlier figure.
Early termination of a two‐stage study to develop and validate a panel of biomarkers

Two-stage designs to develop and validate a panel of biomarkers present a natural setting for the inclusion of stopping rules for futility in the event of poor preliminary estimates of performance. We consider the design of a two-stage study to develop and validate a panel of biomarkers where a predictive model is developed using a subset of the samples in stage 1 and the model is validated using the remainder of the samples in stage 2. First, we illustrate how a stopping rule for futility can be implemented in a standard, two-stage study for developing and validating a predictive model where samples are separated into a training and validation sample. Simulation results indicate that our design has similar type-I error rate and power to the fixed-sample design but with a substantially reduced sample size under the null hypothesis. We then illustrate how additional interim analyses can be included in stage 2 by applying existing group sequential methodology, which results in even greater savings in the number of samples required under both the null and alternative. Our simulation results also illustrate that the operating characteristics of our design are robust to changes in the underlying marker distribution.
Toll-Like Receptor 3 Mediates Establishment of an Antiviral State against Hepatitis C Virus in Hepatoma Cells

Toll-like receptor-3 (TLR3) senses double-stranded RNA, initiating signaling that activates NF-kappaB and interferon regulatory factor 3 (IRF-3), thereby inducing the synthesis of proinflammatory cytokines, type I interferons, and numerous interferon-stimulated genes (ISGs). This pathway has not been extensively investigated in human hepatocytes, and its role in sensing and protecting against hepatitis virus infections is uncertain. We show here that primary human hepatocytes express TLR3 and robustly upregulate ISGs upon poly(I.C) stimulation. We also show that TLR3 senses hepatitis C virus (HCV) infection when expressed in permissive hepatoma cells, acting independently of retinoic acid-inducible gene I and inducing IRF-3 activation and the synthesis of ISGs that restrict virus replication. In turn, HCV infection reduces the abundance of TRIF, an essential TLR3 adaptor, and impairs poly(I.C)-induced signaling. The induction and disruption of TLR3 signaling by HCV may be important factors in determining the outcome of infection and the ability of HCV to establish persistent infections.
Bioavailability of Synthetic Ascorbic Acid and a Citrus Extract

Introduction There is now considerable general interest in Vitamin C supplementation due to recent popular books on the treatment of the common cold and cancer by ascorbic acid (AA). Also, certain populations such as smokers and the elderly are known to be deficient in AA [1, 2] and would benefit from supplementation. Although natural and synthetic AA are chemically identical, citrus fruits contain bioflavonoids that might affect the bioavailability of AA.
Validation of frontal near-infrared spectroscopy as noninvasive bedside monitoring for regional cerebral blood flow in brain-injured patients.

Object Near-infrared spectroscopy (NIRS) offers noninvasive bedside measurement of direct regional cerebral arteriovenous (mixed) brain oxygenation. To validate the accuracy of this monitoring technique, the authors analyzed the statistical correlation of NIRS and CT perfusion with respect to regional cerebral blood flow (CBF) measurements. Methods The authors retrospectively reviewed all cases in which NIRS measurements were obtained at a single, academic neurointensive care unit from February 2008 to June 2011 in which CT perfusion was performed at the same time as NIRS data was collected. Regions of interest were obtained 2.5 cm below the NIRS bifrontal scalp probe on CT perfusion with an average volume between 2 and 4 ml, with mean CBF values used for purposes of analysis. Linear regression analysis was performed for NIRS and CBF values. Results The study included 8 patients (2 men, 6 women), 6 of whom suffered subarachnoid hemorrhage, 1 ischemic stroke, and 1 intracerebral hemorrhage and brain edema....
Immunolocalization of LeAGP-1, a modular arabinogalactan-protein, reveals its developmentally regulated expression in tomato

Arabinogalactan-proteins (AGPs) are highly glycosylated cell surface proteins that are thought to function in plant growth and development. The developmentally regulated expression of LeAGP-1, a novel and major AGP in tomato, was examined in different organs and tissues of tomato (Lycopersicon esculentum Mill. cv. UC82B) plants with an anti-peptide antibody (i.e. the PAP antibody) directed specifically against the lysine-rich subdomain of the LeAGP-1 core protein. During cell differentiation in tomato plants, LeAGP-1 was associated with cell wall thickening and lignification of particular cell types. Specifically, LeAGP-1 was detected in secondary wall thickenings of maturing metaxylem and secondary xylem tracheary elements in roots and stems, and in thickened cell walls of phloem sieve elements. However, LeAGP-1 was also present in thin-walled, cortical parenchyma cells of seedling roots as well as thick-walled collenchyma cells in young stems, both of which are not lignified. Based on these observed patterns, possible roles for LeAGP-1 in plant growth and development are discussed.
The Menacanthus (Mallophaga: Menoponidae) of the passeriformes (Aves).

Twenty-eight species of Menacanthus are recognized, discussed, and keyed. These include 7 new species with the following type-hosts: M. sturnellae from Sturnella magna, M. quiscali from Quiscalus quiscula, M. tyranni from Tyrannus verticalis, M. obsoleti from Salpincles obsoletus, M. aedonis from Troglodytes aedon, M. dendroicae from Dendroica discolor , and M. geothlypis from Geothlypis trichas . There are 23 new synonymies and 6 names listed as nomina dubia. Neotypes are erected for Pediculus curuccae Schrank and Menopon pusillum Nitzsch; lectotypes are designated for Colpocephalum chrysophaeum Kellogg and Menopon distinctum Kellogg & Chapman.
Design and simulation of a cockroach-like hexapod robot

This paper describes the design and simulation of a cockroach-like hexapod robot which is under construction for the purpose of testing control principles which are being extracted from the cockroach. The cockroach was chosen because of its remarkable running and climbing capabilities and because much is known about its biomechanics and control. The robot is designed with five, four, and three degrees of freedom in the front, middle and rear legs, respectively, to permit it to mimic the different functions of cockroach legs. Pneumatic cylinders actuate each joint and provide opposing muscle-like forces to actuate the joints. Pulse-width modulation controls the actuators with the necessary smoothness and precision. A dynamic simulation has been developed to predict loads on the structure and the required joint torques.
ASFinder: a tool for genome-wide identification of alternatively splicing transcripts from EST-derived sequences

Expressed Sequence Tags ESTs are a rich resource for identifying Alternatively Splicing AS genes. The ASFinder webserver is designed to identify AS isoforms from EST-derived sequences. Two approaches are implemented in ASFinder. If no genomic sequences are provided, the server performs a local BLASTN to identify AS isoforms from ESTs having both ends aligned but an internal segment unaligned. Otherwise, ASFinder uses SIM4 to map ESTs to the genome, then the overlapping ESTs that are mapped to the same genomic locus and have internal variable exon/intron boundaries are identified as AS isoforms. The tool is available at http://proteomics.ysu.edu/tools/ASFinder.html.
Information exchange needs for new fault location applications in T&D systems

This paper investigates new applications that reduce the impact of outages in power systems, which are made possible with expanded data acquisition and communication solutions introduced through the development of smart grid. Requirements for such applications are highlighted by studying their use cases. Standards associated with data formats and communication protocols facilitating data integration are also identified.
Servo Control of the GS16 Turbine Gas Metering Valve by Physics-Based μ-Synthesis

We present a design approach using μ- synthesis which returns a controller in observor/state-feedback form with physically meaningful states. The advantages of this physics-based approach are illustrated by a detailed outline of the controller design for Woodward governor's GS16 turbine gas metering valve.
A Simple, Robust Leadtime-Quoting Policy

We examine leadtime-quoting polices for minimizing average lead time subject to customer service constraints on fill rate, tardiness, or relative tardiness in simple systems with exponential and normal processing times. By studying the resulting safety leadtimes implied by each policy we gain insight into why some policies perform more robustly with respect to different measures of customer service than do others. This analysis suggests that a simple constant safety leadtime policy should work reasonably well under most conditions. A series of simulation experiments of more complex production environments indicates that the constant safety leadtime policy does indeed exhibit robust performance. This, plus the fact that it is extremely simple to adapt to a wide range of production environments, makes it an attractive basis for real-world leadtime-quoting systems.
MEASUREMENT OF DAMPING IN STRUCTURES BY THE POWER INPUT METHOD

Damping refers to the extraction of mechanical energy from a vibrating system usually by conversion of this energy into heat. Damping serves to control the steady-state resonant response and to attenuate traveling waves in the structure. There are two types of damping: material damping and system damping. Material damping is the damping inherent in the material while system or structural damping includes the damping at the supports, boundaries, joints, interfaces, etc. in addition to material damping.
Paracellin-1 and the modulation of ion selectivity of tight junctions

Tight junctions play a key selectivity role in the paracellular conductance of ions. Paracellin-1 is a member of the tight junction claudin protein family and mutations in the paracellin-1 gene cause a human hereditary disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) with severe renal Mg2+ wasting. The mechanism of paracellin-1 function and its role in FHHNC are not known. Here, we report that in LLC-PK1 epithelial cells paracellin-1 modulated the ion selectivity of the tight junction by selectively and significantly increasing the permeability of Na+ (with no effects on Cl-) and generated a high permeability ratio of Na+ to Cl-. Mutagenesis studies identified a locus of amino acids in paracellin-1 critical for this function. Mg2+ flux across cell monolayers showed a far less-pronounced change (compared to monovalent alkali cations) following exogenous protein expression, suggesting that paracellin-1 did not form Mg2+-selective paracellular channels. We hypothesize that in the thick ascending limb of the nephron, paracellin-1 dysfunction, with a concomitant loss of cation selectivity, could contribute to the dissipation of the lumen-positive potential that is the driving force for the reabsorption of Mg2+.
The relationship between serum uric acid and chronic kidney disease among Appalachian adults

Background. Higher serum uric acid (SUA) levels have been shown to be associated with cardiovascular disease. SUA levels are also associated with hypertension, a strong risk factor for chronic kidney disease (CKD). However, it is unclear whether SUA is independently associated with CKD. We examined the hypothesis that higher SUA levels are positively associated with CKD. Methods. We analysed data from the C8 Health Study, a population-based study of Appalachian adults aged ≥18 years and free of cardiovascular disease (n = 49,295, 53% women). SUA was examined as gender-specific quartiles. The outcome of interest was CKD (n = 2,980), defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m2 from serum creatinine. Results. Overall, we observed a clear positive association between increasing quartiles of SUA and CKD, independent of confounders. Compared with the lowest quartile of SUA (referent), the multivariable odds ratios (95% confidence interval) for quartiles 2–4, respectively, of CKD were 1.53 (1.31, 1.78), 2.16 (1.86 2.50) and 4.67 (4.07, 5.36); P-trend < 0.0001. This observed positive association persisted in separate analysis among men (P-trend < 0.0001) and women (P-trend < 0.0001). Conclusions. In conclusion, higher SUA levels are positively associated with CKD, suggesting that at least part of the reported association between SUA and cardiovascular disease may be mediated by CKD.
Routing in rectilinear polygons

The author presents an algorithm for routing nets in a generic rectilinear polygon. The algorithm constructs a routing if one exists. The number of wire bends in the constructed routing is minimized and is upper bounded by O(m). The time complexity of the algorithm is O(m log/sup 2/m), where m is the number of vertices on the boundary of the polygon. The algorithm can be applied to many VLSI routing problems, such as switch-box, channel, junction, and convex grids routings. >
Modelling hydrological processes in created freshwater wetlands: an integrated system approach

Abstract This study investigates hydrologic processes of four different flow-through created freshwater wetlands in Ohio, USA, by use of several versions of a simple daily mass-balance water budget model. The model includes surface inflows and outflows, precipitation, evapotranspiration, and groundwater seepage. We calibrated the daily water budget for two experimental wetlands that had pumped inflow during 1999 and validated it during 2000–2002 on the same basins. The coefficient of prediction efficiency is 0.70 and the modelled hydroperiod followed observed water depths during the calibration period well. The average retention time in the calibration year 1999 was 4.4–4.6 days. The model was applied to a 3-ha created riparian wetland that receives river flooding. Results illustrated that this wetland has developed a hydroperiod with more than sufficient flooding to ensure that it will meet the hydrologic criteria of a formal jurisdictional wetland definition in the USA. Water budget predictions for a stormwater wetland provided useful design information for hydroperiod and hydrologic dynamics prior to the construction of that system. The model was simulated for average, dry, and wet years. An integrated systems approach was developed using a STELLA 7.0 with its capabilities of dynamic interface level control (e.g. buttons and switches) features.
Protein Restriction to Pregnant Rats Increases the Plasma Levels of Angiotensin II and Expression of Angiotensin II Receptors in Uterine Arteries

Whether gestational protein restriction affects the renin-angiotensin system (RAS) in uterine artery remains unknown. In this study, we hypothesized that gestational protein restriction alters the expression of RAS components in uterine artery. In study one, time-scheduled pregnant Sprague Dawley rats were fed a normal or low-protein (LP) diet from Day 3 of pregnancy until they were killed at Days 19 and 22. The uterine arteries were collected and used for gene expression of Ace, Ace2, Agtr1a, Agtr1b, Agtr2, Esr1, and Esr2 by quantitative real-time PCR and/or Western blotting. LP increased plasma levels of angiotensin II in pregnant rats. In the uterine artery, the expressions of Agtr1a, Agtr1b, and Esr1 were increased by LP at Days 19 and 22 of pregnancy, whereas the abundance of AGTR1 and AGTR2 was increased by LP at Day 19 of pregnancy. The expression of Ace2 was not detectable in rat uterine artery. In study two, virgin female rats were ovariectomized and implanted with either 17beta-estradiol (E2), progesterone (P4), both E2 and P4, or placebo pellets until they were killed 7 days later. In rat uterine artery, E2 and P4 reduced the expression of Agtr1a, and E2 increased the expression of Agtr1b and Agtr2, but neither E2 nor P4 regulated the expression of Ace. These results indicate that gestational protein restriction induces an increase in Agtr1 expression in uterine artery, and thus may exacerbate the vasoconstriction to elevated angiotensin II present in maternal circulation, and that female sex hormones also play a role in this process.
Comparing robust properties of A, D, E and G-optimal designs

We examine the A, D, E and G-efficiencies of using the optimal design for the polynomial regression model of degree k when the hypothesized model is of degree j and 1 Q j < k Q 8. The robustness properties of each of these optimal designs with respect to the other optimal&y criteria are also investigated. Relationships among these efficiencies are noted and practical implications of the results are discussed. In particular, our numerical results show E-optimal designs possess several properties not shared by the A, D and G-optimal designs.
Light emission and subsequent tree inception due to polarity reversal of the local field in polymeric insulation

The authors describe the treeing characteristics of normal and degassed low-density polyethylene under AC, DC, and half-rectified AC voltages. By individually controlling the amplitudes of the positive and negative half-cycles of the AC voltage, it is shown that the polarity reversal of the local field in the polymer plays a crucial role for light emission and subsequent tree inception. If light is not emitted, then treeing does not occur, because it is impossible for the unipolar injected charge to gain sufficient energy to cause impact ionization or break bonds of the polymer chain. The injection of electrons and holes and their recombination at luminescent centers gives rise to light having spectra in the visible and the UV (ultraviolet) ranges. The UV light photodegrades the polymer and leads to the formation of an electrical tree. >
The effect of phosphate concentration on growth and agar content of Gelidium robustum (Gelidiaceae, Rhodophyta) in culture

Phosphate concentration of the growth medium was found to affect the growth rate and agar yield of a clone of Gelidium robustum grown in the laboratory. To study differences in growth we used phosphate concentrations from 0 to 200 µM. To determine the effect of phosphate on agar yield and its properties we used concentrations from 0 to 20 µM. Growth rates generally increased with increasing phosphate concentration, with the highest growth rate (21% d-1) obtained at 150 µM. Agar yield as percentage of fresh weight was highest (10%) in the algae grown with low phosphate concentrations, but agar yield as percentage of dry weight was highest(43%) at 20 µM of phosphate. Gel strength increased with phosphate concentration with a maximum of 160 g m-2 for 0.75% gels for the cultures at 20 µM. Melting and gelling temperatures of the gels were also affected by phosphate concentration of the growth medium. Starch yield was highest in algae grown in low phosphate concentrations.
EMT domestic violence knowledge and the results of an educational intervention

The objective of this study was to determine levels of knowledge regarding domestic violence (DV), and the effectiveness of formal instruction about DV. A general knowledge survey of DV was given before and approximately 4 to 6 months after 3 hours of instruction given by Emergency Medicine and Law Enforcement faculty. A Emergency medical service (EMS) consisting of 73% paramedic-level providers in a metropolitan urban/suburban area. Differences in DV knowledge before and after the instruction were the main outcome measures. In the preinstruction series, 46 emergency medical technicians (EMTs) participated. After the instruction 19 EMTs participated (42%). Thirty-five percent of EMTs before instruction and 37% after instruction correctly identified the prevalence of DV against women as 15% to 30%. Thirty-five percent of EMTs before instruction and 63% after instruction (P < .05) correctly identified the prevalence of DV against men as 0% to 15%. Before instruction 54% knew that DV is equal among races, and 79% after instruction (P < .05). Before instruction 37% of EMTs knew that DV is equal in different socioeconomic groups and 68% after instruction (P < .05). The percent of EMTs who knew that the victim is not responsible for the abuse was 50% before instruction and 89% after instruction (P < .05). Before instruction, the results on a knowledge questionnaire were 54% correct, after instruction, results improved to 71% correct. Improvement in understanding of DV was shown for 4 of 11 questions after 3 hours of instruction. These results indicate the need for more instruction on DV for EMTs.
Modelling tropical atmospheric convection in the context of the weak temperature gradient approximation

A cumulus ensemble model is used to simulate the interaction between tropical atmospheric convection and the large-scale tropical environment in the context of Sobel and Bretherton's (2000) weak temperature gradient approximation. In this approximation, gravity waves are assumed to redistribute buoyancy anomalies over a broad area of the tropics, thus maintaining the local virtual-temperature profile close to the large-scale mean. This result is implemented in the model by imposing the advective effects of a hypothetical mean vertical velocity which is just sufficient to counteract the local heating induced by convection and radiation. The implied vertical advection in the moisture equation and entrainment of air from the surrounding environment have major effects on the evolution of convection in the model. The precipitation produced by the model mimics the results of a very simple model of tropical precipitation introduced by Raymond (2000), in that the mean rainfall rate predicted by the cumulus ensemble model is, to a good approximation, a function only of the mean column precipitable water. The evolution of the precipitable water, and hence the precipitation rate, is a result of the imbalance between the surface flux of moist entropy into the domain and the radiative loss of entropy out of the top of the domain. This evolution leads to a statistically steady solution in which the resulting precipitation rate is a unique function of the entropy flux imbalance. These results support the hypothesis that tropical precipitation averaged over distance scales of a few hundred kilometres and time scales of a day is a consequence only of local thermodynamic factors. Copyright © 2005 Royal Meteorological Society
Optical channel waveguide switch and coupler using total internal reflection

Light beam switching and coupling in a four-port channel waveguide-horn structure has been accomplished using electrooptic modulation of the critical angle of a refractive index interface in a Y -cut LiNbO 3 substrate. The resulting double-pole double-throw switch/coupler is potentially capable of simultaneously providing a combination of desirable characteristics.
Voltage and ion current measurements for an ion diode driven by mercury in positive polarity with layered mitl flow

For pulsed power machines with an inductive voltage adder (IVA) architecture and a magnetically insulated transmission line (MITL), positive polarity operation results in layered MITL flow as emitted electrons are born at different potentials in each of the adder cells.1 Because of this layered flow, the usual prediction of the voltage using the Mendel formula is not accurate in positive polarity. In an attempt to directly measure the voltage across an ion diode on Mercury in positive polarity2,3, a number of diagnostics have been fielded, including a vacuum wire voltmeter, stacked radiachromic films, nuclear activation, and a 7Li(p, n) neutron-yield technique. Additionally, the ion current produced by the diode is measured using magnetic probes and the proton current is estimated by the same 7Li(p, n) neutron-yield technique. An ion diode model is developed to predict the diode voltage and ion current based on the measured total current. This model is based on previous pinched beam ion diode work4,5 and is only applicable when the diode presents an under-matched load impedance compared with the self-limited impedance of the MITL so that the flow current becomes part of the diode current. The self-limited impedance in positive polarity layered flow on Mercury is also investigated. PIC and circuit simulations are used to analyze the problem as well. The experimental results will be discussed and compared with the theoretical predictions.