cssi/SciSciGPT-SciSciNet huggingface dataset:
Modulation of outward potassium currents in aligned cultures of neonatal rat ventricular myocytes during phorbol ester-induced hypertrophy.

Abstract Protein kinase C-stimulating phorbol esters induce a strong hypertrophic response when applied in vitro to cardiac ventricular myocytes. The aim of this study was to determine if this in vitro model of hypertrophy is associated with changes in the expression of voltage-gated K + channels. Myocytes were isolated from 3–4-day-old neonatal rats and cultured on aligned collagen thin gels. Membrane currents were measured with the use of the whole-cell arrangement of the patch clamp technique and the expression levels of the Kv1.4, Kv4.2 and Kv2.1 α subunits quantified using Western blot analysis. Voltage steps positive to −30 mV resulted in the activation of both a transient (I to ) and a sustained (I sus ) component of outward K + current in the aligned myocytes. Overnight exposure to phorbol 12-myristate 13-acetate (PMA) caused a 55% increase in myocyte size and a three-fold reduction in the peak amplitude of I to . No differences in the half-maximal voltages required for activation and steady-state inactivation were observed between I to measured in control and PMA-treated myocytes. In contrast, PMA treatment resulted in a 62% increase in a tetraethylammonium-sensitive component of I sus (TEA-I sus ) and was associated with the appearance of a slow component of current decay. Expression levels of the Kv1.4 and Kv4.2 α subunits were strongly depressed in the hypertrophic myocytes, while the density of the Kv2.1 α subunit was enhanced. PMA-induced changes in the Kv α subunits were partially prevented through inhibition of the mitogen-activated protein kinase (MAPK) pathway. Thus, PMA-induced hypertrophy of cultured ventricular myocytes is associated with an altered expression of voltage-gated K + channels.
Radio imaging of moving targets: the one-dimensional case (microwave range)

The detection of moving targets by passive radio temperature measurements is studied. A radio image is reconstructed by linear spatial filtering of simultaneous measured brightness samples, obtained by multiple regularly spaced antenna beams. With fixed spatial filters, the receiver integration time must be short enough to freeze motion, thus limiting the signal-to-noise ratio obtained in the reconstruction image. It is shown that in the one-dimensional case a time-varying matched spatial filter yields the same signal-to-noise ratio in the reconstructed image as would be obtained from a stationary target with a fixed matched filter. >
Determining the effective electromagnetic properties of negative-refractive-index metamaterials from internal fields

Effective electromagnetic properties of negative index of refraction metamaterials (NIMs) can be hard to measure. We show through simulations that electromagnetic fields inside a typical, physically realizable wire-SRR (split ring resonator) NIM are more homogeneous than one might expect inside such metamaterials, and sufficiently structured to be useful for interpretation. Specifically, simulations show that the electric field phase is surprisingly smooth inside the NIM, including at the edges of the material, and can thus be used to reliably estimate the effective length of the material, a critical parameter when determining the effective material properties using many methods. The effective length, together with amplitude and phase measurements inside the material, can further be used to measure with good precision and minimum ambiguity the effective material properties of a NIM. To validate this technique, we show that the material properties obtained using it very closely match those derived from $S$ parameters. The inherent redundancy in the field data makes this method less sensitive to measurement errors than one based on transmission/reflection measurements, thus making it suitable for simulations and for experiments. We also show that, for experiments, given the periodicity of the NIM, one measurement per cell is generally enough to retrieve with good precision these material properties.
Repression of jasmonate signaling by a non‐TIFY JAZ protein in Arabidopsis

JAsmonate ZIM-domain (JAZ) proteins repress the activity of transcription factors that execute responses to the plant hormone jasmonoyl-L-isoleucine (JA-Ile). The ZIM protein domain recruits the co-repressors NINJA and TOPLESS to JAZ-bound transcription factors, and contains a highly conserved TIF[F/Y]XG motif that defines the larger family of TIFY proteins to which JAZs belong. Here, we report that diverse plant species contain genes encoding putative non-TIFY JAZ proteins, including a previously unrecognized JAZ repressor in Arabidopsis (JAZ13, encoded by At3g22275). JAZ13 is most closely related to JAZ8 and includes divergent EAR, TIFY/ZIM, and Jas motifs. Unlike JAZ8, however, JAZ13 contains a Ser-rich C-terminal tail that is a site for phosphorylation. Overexpression of JAZ13 resulted in reduced sensitivity to JA, attenuation of wound-induced expression of JA-response genes, and decreased resistance to insect herbivory. JAZ13 interacts with the bHLH transcription factor MYC2 and the co-repressor TOPLESS but, consistent with the absence of a TIFY motif, neither NINJA nor other JAZs. Analysis of single and higher-order T-DNA insertion jaz null mutants provided further evidence that JAZ13 is a repressor JA signaling. Our results demonstrate that proteins outside the TIFY family are functional JAZ repressors and further suggest that this expansion of the JAZ family allows fine-tuning of JA-mediated transcriptional responses.
Service encounters and service relationships: Implications for research

Abstract The essentially social nature of service encounters, a short-run phenomenon, provides the occasions in which buyer and seller negotiate the terms of their exchange relationship, a long-run phenomenon. Defined as the mutual recognition of special status between exchange partners, exchange relationships insure efficacy for the buyer, as they mitigate market volatility for the seller. Understanding how economic exchange is played out against a background of social exchange can yield actionable insights. One implication is that research must include both customer and provider perceptions as the focal unit. Other research implications include the need to study the impact of customer role performance on satisfaction, to identify the elements of style and substance that buyers or sellers use to judge relational performance, and the need to develop measures of relational quality and strength.
Absence of the pulmonary valve associated with ventricular septal defect.

Abstract 1. (1) A case of congenital absent pulmonic valve with ventricular septal defect in a fiveweek-old male is presented. 2. (2) The clinical findings of this patient, suggesting severe pulmonic regurgitation and ventricular septal defect, are discussed in order to define diagnostic criteria for this malformation.
Finding all minimum‐size separating vertex sets in a graph

We present a new algorithm based upon network flows for finding all minimum-size separating vertex sets in an undirected and unweighted graph. The sequential implementation of our algorithm runs in Θ(Mn + C) = O(2kn3) time, where M is the number of minimum-size separating vertex sets of the graph; n, the number of the vertices in the graph; m, the number of the edges in the graph; k, the connectivity of the graph, and C = kn min(k(m + n), A), where A is the complexity of the best maximum flow algorithm for unit networks. The parallel implementation runs either in O(k log n) deterministic time or in O(log2n) randomized time using Θ(;M2n2 + knNα) = O(4k(n6/k2)) processors on a PRAM, where Nα is the number of processors needed for parallel matrix multiplication in O(log n) time on PRAM. © 1993 by John Wiley & Sons, Inc.
Perspective on the current state of macroeconomic theory

Historically, microeconomics was the domain of scientific methodology in economics, while macroeconomics attacted less mathematically oriented economists. In recent years, the level of sophistication of macroeconomics has grown dramatically, and that field now attracts many of the most mathematically oriented economists. Nevertheless, the field's set of shared views (i.e. maintained hypotheses) has not grown. The purpose of the scientific method is to permit the maintained hypotheses within a field to grow by establishing a rigorous methodology for deductively deriving and empirically testing hypotheses. The field of macroeconomics has failed that test of scientific success during precisely the decades of most rapid growth in the use of scientific methodology. It is argued that the source of the paradox lies in the fact that the inroads of science into macroeconomics have been asymmetrical. Central to the definition and objectives of macroeconomics is dimension reduction and dynamics. Rigorous dimension r...
Application of FRP laminates for strengthening of a reinforced-concrete T-beam bridge structure

This paper describes application of fiber-reinforced polymer (FRP) composite laminates to strengthen an aging reinforced-concrete T-beam bridge in South Troy, Rensselaer County, New York. Leakage at the end joints of this single-span structure led to substantial moisture and salt infiltration in the bridge superstructure. Presence of efflorescence was observed, and freeze-thaw cracking and concrete delamination at some locations on the beams were noted. Concerns about integrity of the steel reinforcing and overall safety of the bridge were raised. These concerns were heightened by the absence of any documents pertaining to the bridge design, such as rebar size, steel type, concrete strength, and design loads. Thus, a decision was made to strengthen the bridge using bonded FRP-laminates. Load tests were conducted to evaluate effectiveness of the strengthening system and investigate its effect on structural behavior, and tests results were compared with those obtained using classical analysis.
Terrestrial black hole for measuring high-rejection off-axis response

An off-axis scatter facility was developed to support the Space Dynamics Laboratory in a number of earth limb measurement programs where the off-axis performance of the sensors was critical to the validity of the data. The facility was developed from three fundamental assumptions. (1) Careful control of any light scattered from the optical system being measured to make certain that it did not return to re-enter the system and corrupt the measurement. (2) Use of black specular surfaces in a unique shape to direct and attenuate scattered light. (3) Utilization of clean room technology to filter air to reduce scattering from particulates in the air and to prevent dust from degrading the specularity of the special surfaces. Therewithal analyses of atmospheric and surface scattering showed that surface scattering effects could be suppressed below atmospheric scattering limits by use of properly shaped specular walls. Analysis of measurements made in the facility demonstrated that the measurements were limited by Rayleigh scattering from the air molecules in the facility and not from dust or water droplets in the air nor from scattering from any chamber surfaces. Measurements of the Cassini narrow field camera showed a noise floor at 2.8E-12 of on-axis response.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Evolution of Holed Nanostructures on GaAs (001)

We studied the evolution of holed nanostructures by gallium droplet epitaxy on a GaAs surface. A linear relationship between the height and diameter of outer rings from holed nanostructures was found. Further, an empirical rule to predict the ratio of height to outer ring diameter for Ga and In holed nanostructures was established. This rule provides deeper insights to quantum rings formation from droplet materials.
The Narcotrafficker in Representation and Practice: A Cultural Persona from the U.S.-Mexican Border

This article proposes a type of cultural model of the self called a “cultural persona” that acts as a nexus between representation and practice, using evidence from ethnographic work in the U.S.–Mexico border region on popular interpretations of the narcotrafficker, particularly as represented via a popular song genre called the “narcocorrido,” and listener interpretations. Narcocorridos, in the form of a traditional border song called the “corrido” that typically portrayed actions of populist heroes (e.g., Pancho Villa), are narratives about the character and exploits of narcotraffickers. The paper looks at both popular and media industry interpretations of the narcotrafficker persona, the articulation of mass media imperatives on the persona, examples of individuals drawing on that persona in their own self-presentation, and connections between corridos and the self.
Effect of Reverse Micelle Size on the Librational Band of Confined Water and Methanol

We report measurement of the OH librational band in nanoscopic pools of water and methanol confined within reverse micelles. The librational band, which peaks near 670 cm-1 in the bulk liquids, shifts to lower frequency as the reverse micelle size decreases. In addition, the shape of the band changes considerably as a function of decreasing size. The librational band at all compositions is well fit by a two-state model based on the relative fractions of bound and free water (or methanol) within the reverse micelles.
Group Analysis for Functional Optical Brain Imaging using a Random Effects Model

To date, group analysis methods in diffuse optical imaging have been largely restricted to analysis of region-of-interest information. We describe a random-effects imaging (inverse) model for calculating group statistics.
Laser schlieren microphone for optoacoustic spectroscopy.

This paper describes a laser schlieren microphone, where a low-power He–Ne laser beam is deflected by a reflecting diaphragm mounted on an optoacoustic Helmholtz resonator. The sinusoidal pressure variations in the resonator distort the surface of the diaphragm so that the reflected laser beam is alternately focused and defocused. The deflection is converted into an amplitude modulation of the beam by an iris located at a distance from the resonator and detected with a photodiode. The light beam can be modulated at a high frequency and the signal from the photodiode processed with a lock-in amplifier so that noise with a power spectral density proportional to the inverse of the frequency is significantly reduced in the final optoacoustic signal. A mathematical description of the laser schlieren microphone is given that shows the system to respond linearly to small signals. An experiment was done to determine the range of linear response of the microphone to large amplitude optoacoustic signals.
Laser skin friction measurements and CFD comparison of weak-to-strong swept shock/boundary-layer interactions

A joint experimental and computational study of skin friction in weak-to-strong swept shock wave/turbulent boundary-layer interactions has been carried out. A planar shock wave is generated by a sharp fin at angles of attack alpha = 10 deg and 16 deg at M(infinity) = 3 and 16 and 20 deg at M(infinity) = 4. Measurements are made using the Laser Interferometer Skin Friction meter, which optically detects the rate of thinning of an oil film applied to the test surface. The results show a systematic rise in the peak c(f) at the rear part of the interaction, where the separated flow atttaches. For the stronget case studied, this peak is an order of magnitude higher than the incoming freestream c(f)level.
The Performance of Randomization Tests that Use Permutations of Independent Variables

In this article we evaluate the performance of a randomization test for a subset of regression coefficients in a linear model. This randomization test is based on random permutations of the independent variables. It is shown that the method maintains its level of significance, except for extreme situations, and has power that approximates the power of another randomization test, which is based on the permutation of residuals from the reduced model. We also show, via an example, that the method of permuting independent variables is more valuable than other randomization methods because it can be used in connection with the downweighting of outliers.
Is PSR1957 + 20 eclipsed by a comet, magnetosphere or particulate cloud?

The extraordinary eclipsing binary pulsar PSR1957 + 20 is in eclipse over eight per cent of its orbit1. This is more than twice the extent of the companion's Roche lobe, the maximum stable synchronous configuration. A possible explanation2 for the large eclipse is that it is caused by a plasma wind driven from the companion and forming a comet-like tail3. But an ionized cometary tail implies a refractive eclipse, which would produce large variations in pulse arrival times; this is inconsistent with the small time delays observed. Here we suggest two alternative explanations. One possibility is that the companion has a typical white-dwarf magnetic field (∼ 105 gauss), and that the eclipse is then due to the plasma-filled magnetosphere which is confined and blown back sharply by the pulsar wind, with the time delays produced by a much less dense tail. In the other limit of negligible magnetization of the companion, an eclipse could be caused by a particulate cloud (comprising particles of size ∼ 10 cm) which should form about the companion. We assume that the companion is the remnant of an evolved companion star that is now being excited by the 622-Hz pulsar radiation. Such excitation could either supply plasma to the magnetosphere (for the magnetized case) or pull off neutral gas and deposit it in the vicinity to sustain a particulate cloud (for the non-magnetized case). Near-infrared radiation from this variable system might test the cloud hypothesis, whereas time delays in a magnetized tail suggest radio-frequency polarization tests for the magnetosphere model.
Life, the Universe and nomenclature

Bruce Gibb discusses how and why chemists name reactions and molecules — and what makes such monikers stick.
Abstractionist versus episodic theories of repetition priming and word identification

This paper reviews research relevant to the question of whether words are identified through the use of abstract lexical representations, specific episodic representations, or both. Several lines of evidence indicate that specific episodes participate in word identification. First, pure abstractionist theories can explain short-term but not long-term repetition priming. Second, long-term repetition priming is sensitive to changes in surface features or episodic context between presentations of a word. Finally, long-term priming for pseudowords is also difficult for pure abstractionist theories to explain. Alternative approaches to word identification are discussed, including both pure episodic theories and theories in which both episodes and abstract representations play a role.
Hallux Rigidus: What Lies Beyond Fusion, Resectional Arthroplasty, and Implants

Hallux rigidus (HR) is the limitation of motion at the first metatarsophalangeal (MTP) joint, most commonly secondary to degenerative arthritis. Surgical options for treating HR include 2 general categories: joint salvage and joint destruction. A hybrid of techniques from the 2 categories has emerged: cartilage resurfacing, interpositional arthroplasty, and arthrodiastasis. These procedures address the pathologic condition of the first MTP joint more directly than joint salvage and avoid many of the negative complications, consequences, and connotations of joint destruction procedures. Alternative surgical options for the treatment of recalcitrant pain associated with HR are evolving and are discussed in this review.
A robust digital method for film contrast correction in subtraction radiography

Digital subtraction radiography requires close matching of the contrast in the films to be subtracted. A digital melhod is presented permitting the retrospective correction of film contrast differences. The method is nonparanietri c and derives the required gray level transformation directly from the histograms associated with the radiographs. This transform is shown to be unique and monotonic. It is based on fewer theoretical assumptions than a previously described parametric correction method, and it performs significantly better in reducing the contrast mismatch measured by the standard deviation of the gray levels in the subtraction image.
Summertime cooling of the shallow continental shelf

[1] In summer on the shallow New England continental shelf, near the coast the water temperature is much cooler than the observed surface heat flux suggests. Using depth-integrated heat budgets in 12 and 27 m water depth calculated from observed surface heat flux, water temperature, and velocity, we demonstrate that on time scales of weeks to months the water is persistently cooled due to a mean upwelling circulation. Because the mean wind is weak, that mean circulation is likely not wind driven; it is partly a tidal residual circulation. A feedback exists between the cross-shelf and surface heat fluxes: the two fluxes remain nearly in balance for months, so the water temperature is nearly constant in spite of strong surface heating (the heat budget is two-dimensional). A conceptual model explains the feedback mechanism: the short flushing time of the shallow shelf produces a near steady state heat balance, regardless of the exact form of the circulation, and the feedback is via the influence of surface heating on temperature stratification. Along-shelf heat flux divergence is apparently small compared to the surface and cross-shelf heat flux divergences on time scales of weeks to months. Heat transport due to Stokes drift from surface gravity waves is substantial, warms the shallow shelf in summer, and was previously ignored. In winter, the surface heat flux dominates and the observed water temperature is close to the temperature predicted from surface cooling (the heat budget is one-dimensional); weak winter stratification makes the cross-shelf heat flux small even during strong cross-shelf circulation.
Oxidation and nitrosylation of oxyhemoglobin by S-nitrosoglutathione via nitroxyl anion

The reaction between low molecular weight S-nitrosothiols and hemoglobin is often used to synthesize S-nitrosohemoglobin, a form of hemoglobin suggested to be involved in the regulation of vascular oxygen delivery. However, this reaction has not been studied in detail, and several groups have reported a variable co-formation of oxidized methemoglobin (metHb) during synthesis. This study examines the mechanism of metHb formation and shows that nitrosylhemoglobin (HbNO) can also be formed. Generation of metHb and HbNO is largely dependent on the presence of protein thiol groups. We present evidence for a mechanism for the formation of metHb and HbNO involving the intermediacy of nitroxyl anion. Specifically, the reaction of nitroxyl with S-nitrosothiols to liberate nitric oxide and reduced thiol is proposed to be central to the reaction mechanism.
Is there a common chemical model for life in the universe

A review of organic chemistry suggests that life, a chemical system capable of Darwinian evolution, may exist in a wide range of environments. These include non-aqueous solvent systems at low temperatures, or even supercritical dihydrogen–helium mixtures. The only absolute requirements may be a thermodynamic disequilibrium and temperatures consistent with chemical bonding. A solvent system, availability of elements such as carbon, hydrogen, oxygen and nitrogen, certain thermodynamic features of metabolic pathways, and the opportunity for isolation, may also define habitable environments. If we constrain life to water, more specific criteria can be proposed, including soluble metabolites, genetic materials with repeating charges, and a well defined temperature range.
Graphs excluding a fixed minor have grids as large as treewidth, with combinatorial and algorithmic applications through bidimensionality

We prove that any H-minor-free graph, for a fixed graph H, of treewidth ω has an Ω(ω) × Ω(ω) grid graph as a minor. Thus grid minors suffice to certify that H-minor-free graphs have large treewidth, up to constant factors. This strong relationship was previously known for the special cases of planar graphs and bounded-genus graphs, and is known not to hold for general graphs. The approach of this paper can be viewed more generally as a framework for extending combinatorial results on planar graphs to hold on H-minor-free graphs for any fixed H. Our result has many combinatorial con-sequences on bidimensionality theory, parameter-treewidth bounds, separator theorems, and bounded local treewidth; each of these combinatorial results has several algorithmic consequences including subexponential fixed-parameter algorithms and approximation algorithms.
An in vivo study of the radioprotective effect of diethyldithiocarbamate (DDC)

We have recently shown that diethyldithiocarbamate (DDC) protects plateau-phase cultures of mammalian cells from radiation. Experiments in vivo have extended our knowledge of the radioprotective properties of DDC and show that the LD50/30 in mice is increased from 780 rad to approximately 1400 rad when non-toxic concentrations of DDC are present prior to the irradiation. When DDC is present during irradiation, the pattern of death of the mice is similar to that seen in the absence of the drug and is quite different from that seen in animals dying of a gastrointestinal syndrome (LD50/7 congruent to 1700 rad). To confirm that the LD50/30 data represent bone marrow protection by DDC, we performed bone marrow CFUS assays with and without the presence of DDC, at the time of in vivo irradiation. The DO of the CFUS is increased from 80 rad in the control animals to 120 rad in the animals that have been pretreated with DDC. In experiments using 35S-labelled DDC, the tissue distribution of the drug in tumor-bearing mice indicates a preferential uptake of DDC in kidney, lung and bone marrow compared to tumor tissue. Based on data from both in vitro and in vivo studies, we believe that DDC shows promise as a radioprotective agent and should be considered for clinical trials.
The Impact of Alcoholism Education on Service Providers, Elders, and Their Family Members

Virginia is the first state in the country to conduct a statewide detection and prevention program for geriatric alcoholism. The project employed a train-the-trainer model in which a core group of trainers received extensive (8-hour) training about alcoholism and aging and, in turn, trained small groups of persons in their local communities in abbreviated (2-hour) sessions. Comparisons of pre- and post-training knowledge test scores revealed statistically significant knowledge gains among both sets of participants. Follow-up surveys to participants provided evidence of the program's continued utility. Interviews with key service providers indicated a substantial impact on a broad spectrum of service systems and a strengthening of interagency coordination. Evidence supports the need for alcoholism education, the effectiveness of a train-the-trainer model in addressing educational needs, and the impact of such a program on the broader service community reaching older adults.
Examining the effect of teachers' adaptations of a middle school science inquiry-oriented curriculum unit on student learning

Reform based curriculum offer a promising avenue to support greater student achievement in science. Yet teachers frequently adapt innovative curriculum when they use them in their own classrooms. In this study, we examine how 19 teachers adapted an inquiry-oriented middle school science curriculum. Specifically, we investigate how teachers' curricular adaptations (amount of time, level of completion, and activity structures), teacher self-efficacy (teacher comfort and student understanding), and teacher experience enacting the unit influenced student learning. Data sources included curriculum surveys, videotape observations of focal teachers, and pre- and post-tests from 1,234 students. Our analyses using hierarchical linear modeling found that 38% of the variance in student gain scores occurred between teachers. Two variables significantly predicted student learning: teacher experience and activity structure. Teachers who had previously taught the inquiry-oriented curriculum had greater student gains. For activity structure, students who completed inves- tigations themselves had greater learning gains compared to students in classrooms who observed their teacher completing the investigations as demonstrations. These findings suggest that it can take time for teachers to effectively use innovative science curriculum. Furthermore, this study provides evidence for the importance of having students actively engaging in inquiry investigations to develop understandings of key science concepts. 2010 Wiley Periodicals, Inc. J Res Sci Teach 48: 149-169, 2011
Regulation of transient outward current in human atrial myocytes by protein tyrosine kinase pathway.

Regulation of Transient Outward Current. Introduction: Regulation of transient outward current (I t o ) in human myocytes is unclear. The present study investigated the effect of protein tyrosine kinase (PTK) inhibitors onI t o in human atrial myocytes. Methods and Results: Atrial myocytes were isolated enzymatically from biopsies of human right atrial appendage obtained from patients undergoing coronary artery bypass surgery. I t o was recorded by the whole-cell patch-clamp technique in voltage-clamp configuration. Two groups of PTK inhibitors, the ATP binding site PTK inhibitors genistein and AG957 and the protein substrate PTK inhibitors ST638 and PP2, significantly inhibited I t o in a concentration-dependent manner, with a potency order of genistein>AG957>ST638>PP2. At test pulse potential of +60 mV, I t o was inhibited by 28% ′ 3%, 59% ′ 3%, and 89% ′ 3% by 15, 50, and 100 μM genistein, respectively. Daidzein and PP3, inactive analogues of genistein and PP2, respectively, did not produce any inhibitory effects on I t o . In addition to the inhibition of I t o amplitude, the protein substrate PTK inhibitors ST638 and PP2 significantly accelerated I t o inactivation (current decay) and delayed recovery from inactivation. Inhibition of protein tyrosine phosphatase partially reversed the effect of genistein. Stimulation or inhibition of serine/ threonine kinases (PKA, PKC, and PKG) did not change I t o or alter the inhibitory response of PTK inhibitors on I t o . Conclusion: In human atrial cells, the PTK pathway plays an important role in the regulation of basal I t o , independent of serine/threonine kinases.
A stable method for the incomplete factorization of H-matrices

Abstract Ahac and Olesky have shown that by using the most diagonal-dominat column as a pivot element for M -matrices was numerically stable. The purpose of this paper is to show that this method of selecting a pivoting is stable when finding the incomplete factorization of an H -matrix.
Temporal discontinuities in precipitation in the central north american prairie

Understanding the potential for future climate change to affect ecosystems or agriculture in a region will depend, in part, on understanding how variable the present climate is and what its present effects are. Because the central prairie region of North America undergoes short-term climate shifts (particularly drought), and appears sensitive to these changes, we were interested in characterizing the duration and nature of precipitation fluctuations. We used split, moving-window dissimilarity analysis to locate transition points between periods of relatively homogeneous rainfall over the Kansas region. We identified statistically significant discontinuities in precipitation that appear to represent shifts in the regional climate during the last 115 years. All of the transitions were associated with changes in May, June, and July rainfall. Drought and drought cycles were the dominant fluctuations over decade-long periods. Over somewhat longer periods (20–30 years) there were transitions, varying in abruptness, that may also be related to drought or perhaps larger scale climatic fluctuations. The relatively strong periodicity shown by the decadal discontinuities supports the contention that drought climates are triggered, or ended, by a cyclic phenomenon. The use of dissimilarity analysis allowed us to identify fluctuations in climate of the central North American prairie that were not previously described, and that may have been significant enough to influence natural and agricultural ecosystems.
Public service budget constraints: the perspective of rural officials in the U.S.A.

Abstract Eight counties in the State of Washington served as the focus for a study of issues associated with budget cutbacks. Secondary data were collected from published sources. A mail survey in 1984 of elected and appointed officials provided primary data. The secondary data enabled us to trace changes in expenditure patterns for specific services from 1979 to 1983. Judicial, law enforcement, correctional units and general government received consistent increases, in part because of state mandates. Environmental protection, planning, community development, parks and recreation tended to be cut rather consistently. Social and health services, physical services (roads, bridges, etc.), and education remained relatively stable in most counties. Public officials consider state requirements for improvement in correctional and law enforcement services as the major factor in setting budget priorities. Cutbacks in federal and state funds for environmental protection are part of the basis for county cutbacks, but local priorities appear to support such actions. Despite budget decreases in some service categories, public officials felt that little had been lost in service quality or quantity, although maintenance of plant, equipment, and capital outlays were thought to have suffered rather seriously.
MATPLM1, A MATLAB script for scoring of periodic limb movements: preliminary validation with visual scoring.

Abstract Background and Purpose A Matrix Laboratory (MATLAB) script (MATPLM1) was developed to rigorously apply World Associations of Sleep Medicine (WASM) scoring criteria for periodic limb movements in sleep (PLMS) from bilateral electromyographic (EMG) leg recordings. This study compares MATPLM1 with both standard technician and expert detailed visual PLMS scoring. Methods and Subjects Validation was based on a ‘macro' level by agreement for PLMS/h during a night recording and on a ‘micro' level by agreement for the detection of each PLMS from a stratified random sample for each subject. Data available for these analyses were from 15 restless leg syndrome (RLS) (age: 61.5 ± 8.5, 60% female) and nine control subjects (age: 61.4 ± 7.1, 67% female) participating in another study. Results In the ‘micro' analysis, MATPLM1 and the visual detection of PLMS events agreed 87.7% for technician scoring and 94.4% for expert scoring. The technician and MATPLM1 scoring disagreements were checked for 36 randomly selected events, 97% involved clear technician-scoring error. In the ‘macro' analysis, MATPLM1 rates of PMLS/h correlated highly with visual scoring by the technician ( r 2 = 0.97) and the expert scorer ( r 2 = 0.99), but the technician scoring was consistently less than MATPLM1: median (quartiles) difference: 10 (5, 23). There was little disagreement with expert scorer [median (quartile) difference: −0.3 (−2.4, 0.3)]. Conclusions The MATPLM1 produces reliable scoring of PLMS that matches expert scoring. The standard visual scoring without careful measuring of events tends to significantly underscore PLMS. These preliminary results support the use of MATPLM1 as a preferred method of scoring PLMS for EMG recordings that are of a good quality and without significant sleep-disordered breathing events.
Dietary restriction in rats and mice: A meta-analysis and review of the evidence for genotype-dependent effects on lifespan

Laboratory survival experiments have shown that dietary restriction (DR) can increase median and maximum lifespan. This paper provides a meta-analysis of laboratory experiments that have evaluated the effects of DR on lifespan in rats and mice (1934-present). In rats, DR increased median lifespan by 14-45% in half of all experiments, but in mice the effects of DR have been much weaker (4-27%). The least favorable effects of DR on lifespan have been observed among inbred rather than non-inbred mouse strains. In fact, some inbred mouse strains do not necessarily live longer with DR, including DBA/2 male mice and several strains from the ILSXISS recombinant inbred panel. Shortening of lifespan with DR has also been observed and confirmed for ILSXISS strain 114. Importantly, all rodent studies may be biased by the effects of laboratory breeding, since one study has shown that median lifespan is not improved by DR in wild-derived mice. These findings suggest that the set of genetic backgrounds studied in rodent DR experiments should be diversified. This will broaden the scope of genotypes studied in aging research, but may also be critical for translation of findings from rodents to historically outbred and genetically heterogeneous primate species.
Impact of a negative breast biopsy on subsequent breast self-examination practice

Abstract Women who practice breast-self examination (BSE) occasionally detect breast lumps that are ultimately biopsied and found to be benign. This research examined the impact of a negative breast biopsy on subsequent BSE practice. A total of 655 women comprised three study groups: 83 women who discovered their breast problem by BSE; 179 women whose lump was identified by an individual/procedure in the health care system; and 393 women with no history of breast problems. Telephone interviews determined BSE practice for 6-month intervals prior to, and after, the benign biopsy experience. Among previously-regular practitioners, 21% of the self-discovered group and 16% of those whose lump was discovered in the health care system reduced their BSE practice below the recommended monthly interval following the benign biopsy. In contrast, among initiallynonregular practitioners, 29% of the self-discovered group, and 25% of the health care system group subsequently became regular BSE practitioners. Possible explanations are offered for these opposite shifts in BSE regularity, and some practical suggestions are provided for health care professionals who counsel women following a benign biopsy experience.
Recurrent Foley catheter puncture and displacement: a complication of the use of barbed polyglyconate suture to facilitate vesicourethral anastomosis during robot-assisted radical prostatectomy

Robot-assisted radical prostatectomy (RARP) has been rapidly adopted as an option for surgical management of clinically localized prostate cancer. A challenging aspect of the operation is producing a watertight vesicourethral anastomosis (VUA). The use of unidirectional barbed polyglyconate absorbable suture (V-Loc 180, Covidien, Mansfield, MA, USA) for posterior reconstruction and VUA during RARP was initially described in 2010 [1, 2] and has been shown to safely improve anastomotic times [3–6]. We describe a unique postoperative complication of the use of barbed suture during RARP: recurrent puncture and displacement of the urethral catheter.
How Lipid and Water Physical Chemistry May Control Fusion: Behavior of Membrane Interfaces and Fusion Peptides

Membrane fusion is an essential process in infection by enveloped viruses, synaptic exocytosis, and vesicle trafficking. As interacting membranes are brought together prior to fusion, the resulting membrane-water-membrane interface has surprising and non-bulk-like properties. Here we ask two questions regarding this membrane-membrane interface: how does the physical chemistry differ from bulk, and how do fusion peptides affect this interface. We have used atomistic molecular dynamics simulation to study these interfacial behavior at high resolution. At vesicle-vesicle interfaces prior to fusion, we observe in our simulations a distinct ordering of water between the two membranes and a concomitant slowing of dynamics. We used committor analysis to examine the role of fine water structure in fusion; holding the vesicles fixed while resampling water conformations from a solvent box substantially speeds fusion dynamics, with a small but significant effect on fusion energetics. These slowed dynamics may provide another reason for the reported propensity of fusion stalks to form around the periphery of a contact interface.We have also examined the effect of influenza fusion peptides in bilayers and at membrane interfaces. We and others have previously hypothesized that lipid tail protrusion is a precursor to fusion stalk formation. In our simulations, influenza fusion peptides promote tail protrusion most strongly in a kinked helix conformation with the ends inserted into the hydrophobic layer. Straight helix and helical hairpin conformations occupying an interfacial position promote tail protrusion less strongly.
Self-Reinforcing Isotactic Polypropylene Prepared Using Crystallizable Solvents

A new approach to reinforce and toughen isotactic polypropylene (iPP) with improved processability is evaluated. The concept involves using a crystallizable solvent that, at process temperatures melts, is miscible with the polymer thereby reducing its process viscosity. As the polymer cools, the solvent undergoes thermally induced phase separation (TIPS) to produce crystallites that increase the modulus of the solid through reinforcement and promote an increase in impact resistance by mechanisms similar to rubber-toughened materials. Tetrabromobisphenol-A (TBBPA) is introduced to iPP that forms a homogeneous mixture at elevated temperature and acts as a processing aid, but undergoes phase separation and subsequent crystallization upon cooling to form rigid particles which, in turn, acts as a toughening agent at room temperature. A phase diagram constructed with Flory-Huggins solution thermodynamics shows good agreement with the experimental results. The steady state shear viscosity decreases as TBBPA content increases for the mixtures in melt state, indicating improved processability. The decrease in viscosity enhances crystallization rate of iPP significantly, most likely due to increased diffusivity, while the structure of iPP crystals remain unchanged. Tensile tests show that as TBBPA content increases (up to 15 wt %), the yield stress decreases while elongation at break increases. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Bid-markup determination for microtunneling projects

Abstract Determining the right size of bid-markup is not an easy task for a contractor. The markup must be low enough to ensure a good chance of winning a contract, but high enough to realize a reasonable profit. The determination of proper markup involves the consideration of numerous factors. In the underground construction portions, the factors considered can be increased because of uncertain subsurface conditions. Even though microtunneling has gained in popularity since it was first introduced into North America in 1984, little has been studied as to the contractors’ behavior toward the determination of bid-markup or the systematic bid-markup processes. This paper discusses the key factors that affect the bid-markup decision in the relatively novel construction area and identifies the level of impact of each factor through the use of analytical methods. In addition, a decision support system (DSS) to assist in the selection of appropriate bid-markup for microtunneling projects is developed through survey results and various analytical methods. Finally, a sensitivity analysis is performed.
In Situ Stabilization of Metal-Contaminated Groundwater by Hydrous Ferric Oxide: An Experimental and Modeling Investigation

A potential method is investigated for remediation of metal-contaminated groundwater by in-situ emplacement of an adsorptive coating on the aquifer matrix. The coating is emplaced by sequentially injecting solutes that react as they mix in the aquifer to form a sparingly soluble solid with a high metal-adsorption capacity. Dissolved metals are removed passively as groundwater flows through the treated aquifer. The potential effectiveness of this method was demonstrated by sequentially injecting first ferrous sulfate and then oxygen solutions into a column of unconsolidated sand, producing a coating of hydrous ferric oxide (HFO) as the unretarded oxygen reacted with Fe(II) bound to the sand. The HFO delayed the breakthrough of Cr(VI) and As(V) by 8 and 30 pore volumes, respectively, relative to the unamended material. Attenuation of solutes by the unamended sand was reaction-rate limited, but coupled transport/equilibrium geochemical modeling matched well with the increased metal attenuation by the coating...
Electron capture in highly evolved stars

Electron capture effects on gravitationally contracting iron stars of 1.4 and 2 solar masses
Using Support Vector Machines to Formalize the Valid Input Domain of Models in Data-Driven Predictive Modeling for Systems Design

Predictive modeling can be a valuable tool for systems designers, allowing them to capture and reuse knowledge from a set of observed data related to their system. An important challenge associated with predictive modeling is that of describing the domain over which model predictions are valid. This is necessary to avoid extrapolating beyond the original data, particularly when designers use predictive models in concert with optimizers or other computational routines that search a model’s input space automatically. The general problem of domain description is complicated by the characteristics of observational data sets, which can contain small numbers of samples, can have nonlinear associations among the variables, can be non-convex, and can occur in largely disjoint clusters. Support Vector Machine (SVM) techniques, developed originally in the machine learning community, offer a solution to this problem. This paper is a description of a kernel-based SVM approach that yields a formal mathematical description of the valid input domain of a predictive model. The approach also provides for cluster analysis, which can lead to improved model accuracy through the decomposition of a data set into multiple subsets that designers can model independently. The paper includes a mathematical presentation of kernel-based SVM methods, an explanation of the procedure for applying the approach to predictive modeling problems, and illustrative examples for applying and using the approach in systems design.Copyright © 2009 by ASME
Ice cream shrinkage: a problem for the ice cream industry

When ice cream is shipped from one altitude to another, a change in atmospheric pressure can contribute to shrinkage of the product. Although few recent references exist regarding the problem of shrinkage caused by changes in altitude or pressure, several pertinent articles were published in the 1940s and 1950s. Small air cells, heat shock, high overrun, small ice crystals, improper blending of ingredients, and a wide range of temperature changes during storage are some of the causes of shrinkage in ice cream. Factors reported to reduce shrinkage were 1) factors that tended to produce large air cells and large ice crystals, 2) use of caseinate as an ingredient, 3) higher pasteurization temperature, 4) use of corn syrup instead of cane sugar, 5) reduced milk solids and sugar, 6) higher draining temperature, and 7) use of mono- and diglycerides with polysorbate 80.