cssi/SciSciGPT-SciSciNet huggingface dataset:
Negative Cooperativity of Substrate Binding but Not Enzyme Activity in Wild-type and Mutant Forms of CTP:Glycerol-3-Phosphate Cytidylyltransferase *

Abstract CTP:glycerol-3-phosphate cytidylyltransferase (GCT) catalyzes the synthesis of CDP-glycerol for teichoic acid biosynthesis in certain Gram-positive bacteria. This enzyme is a model for a cytidylyltransferase family that includes the enzymes that synthesize CDP-choline and CDP-ethanolamine for phosphatidylcholine and phosphatidylethanolamine biosynthesis. We have used quenching of intrinsic tryptophan fluorescence to measure binding affinities of substrates to the GCT from Bacillus subtilis. Binding of either CTP or glycerol-3-phosphate to GCT was biphasic, with two binding constants of about 0.1–0.3 and 20–40 μm for each substrate. The stoichiometry of binding was 2 molecules of substrate/enzyme dimer, so the two binding constants represented distinctly different affinities of the enzyme for the first and second molecule of each substrate. The biphasic nature of binding was observed with the wild-type GCT as well as with several mutants with alteredK m or k cat values. This negative cooperativity of binding was also seen when a catalytically defective mutant was saturated with two molecules of CTP and then titrated with glycerol-3-phosphate. Despite the pronounced negative cooperativity of substrate binding, negative cooperativity of enzyme activity was not observed. These data support a mechanism in which catalysis occurs only when the enzyme is fully loaded with 2 molecules of each substrate/enzyme dimer.
Balmer profiles in the geocorona and interstellar space. I - Asymmetries due to fine structure

While the Doppler profiles of Balmer-alpha and -beta are in principle analyzable in order to derive orbital data concerning both escaping and satellite geocoronal particles, interpretations are in practice hampered by a lack of understanding of profile properties apart from such geocoronal features as an asymmetry, caused by the absence of escape velocity-exceeding, downward-directed particles. Attention is accordingly given to the profiles of H atoms which, while emitting radiation from a complete Maxwellian distribution, also exhibit an H-alpha fine structure-generated asymmetry which is a predictable function of the excitation mechanism.
Shedding light on sunscreen biosynthesis in zebrafish

Zebrafish can synthesize a sunscreen compound called gadusol, which was previously thought to be acquired only through the diet.
Parallel Computing on Network of Windows Based PCs

Abstract: This paper describes a dynamic load balancing tool for parallel CFD applications on Microsoft Windows (XP and Vista) based PCs. The tool encourages the PC owners to share the computing resources and provides mechanism to ensure that the parallel jobs do not run on the PCs when their owners are using the computers, while allowing the parallel jobs to use the computers when their owners are not using the computers. The tool has been successfully tested for supporting parallel CFD applications.
Voices From This Long Brown Land: Oral Recollections of Owens Valley Lives and Manzanar Pasts

Nestled between the Sierra Nevada and the White-Inyo mountain ranges in eastern California, the Owens Valley is geographically isolated and spatially bound. Yet this secluded sliver of California p...
Transcriptional Memory: Staying in the Loop

Actively transcribed genes are organized into loops in which the 5' and 3' ends of the gene physically associate. Two new papers show that gene looping can persist after genes are repressed, promoting rapid reactivation of transcription, a phenomenon known as transcriptional memory.
Icebox, a recessive X-linked mutation in Drosophila causing low sexual receptivity.

The X-linked recessive mutation icebox (ibx; 1-23, 7F1) of Drosophila melanogaster lowers the sexual receptivity of females. The probability of mating with mature wild-type males is reduced in ibx homozygotes, and the frequency of rejection behavior (rate per minute) towards courting males is increased, ibx fails to complement In(1)RA35, which is a lethal allele of Neuroglian (Nrg, which encodes a transmembrane protein found in embryonic tissues including the nervous system) due to a breakpoint in that gene; however, both l(1)B4 and l(1)VA142, other lethal mutations of Nrg, do complement ibx. 12-h ibx embryos exhibit a normal pattern of staining for the Neuroglian-specific antibody, Mab BP104. Males and females mutant for ibx have normal egg-to-adult survival and appear normal in several “general” behavioral traits including olfaction, phototaxis, locomotor activity, and heartbeat, ibx males court normally, and are successful in mating. These characteristics suggest that ibx does not cause sensory ormotor...
Low velocity impact response of autoclaved aerated concrete/CFRP sandwich plates

Autoclaved aerated concrete (AAC)-CFRP composites have proven to be structurally efficient combinations for lightweight structural components such as floor beams, lintels, walls or columns. Besides the need to possess adequate flexural properties, AAC/CFRP structures need to be evaluated for their ability to withstand localized damage. During service, the before mentioned structural members are subjected to impact loading that varies from localized object impact, blast due to explosions, or to high velocity impact of debris during tornados, hurricanes, or storms. The objective of this paper is to evaluate the response of AAC/CFRP sandwich structures to low velocity impact (LVI) and to compare the experimental results to the predicted energy absorptions values given by an energy balance model. AAC/CFRP panels are prone to heavy object impacts under relatively low velocities such as in the case of object/tool drops on floor beams or low velocity collisions against columns.
A Mathematical Model for SAR Imaging beyond the First Born Approximation

The assumption of weak scattering is standard for the mathematical analysis of synthetic aperture radar (SAR), as it helps linearize the inverse problem via the first Born approximation and thus makes it amenable to solution. Yet it is not consistent with another common assumption, that the interrogating waves do not penetrate into the target material and get scattered off its surface only, which essentially means that the scattering is strong. In the paper, we revisit the foundations of the SAR ambiguity theory in order to address this and other existing inconsistencies, such as the absence of the Bragg scale in scattering. We introduce a new model for radar targets that allows us to compute the scattered field from first principles. This renders the assumption of weak scattering unnecessary yet keeps the overall inverse scattering problem linear. Finally, we show how one can incorporate the Leontovich boundary condition into SAR ambiguity theory.
Construction of GCCFG for inter-procedural optimizations in software managed manycore (SMM) architectures

Software Managed Manycore (SMM) architectures -- in which each core has only a scratch pad memory (instead of caches), -- are a promising solution for scaling memory hierarchy to hundreds of cores. However, in these architectures, the code and data of the tasks mapped to the cores must be explicitly managed in the software by the compiler. State-of-the-art compiler techniques for SMM architectures require inter-procedural information and analysis. A call graph of the program does not have enough information, and Global CFG, i.e., combining all the control flow graphs of the program has too much information, and becomes too big. As a result, most new techniques have informally defined and used GCCFG (Global Call Control Flow Graph) -- a whole program representation which captures the control-flow as well as function call information in a succinct way -- to perform inter-procedural analysis. However, how to construct it has not been shown yet. We find that for several simple call and control flow graphs, constructing GCCFG is relatively straightforward, but there are several cases in common applications where unique graph transformation is needed in order to formally and correctly construct the GCCFG. This paper fills this gap, and develops graph transformations to allow the construction of GCCFG in (almost) all cases. Our experiments show that by using succinct representation (GCCFG) rather than elaborate representation (GlobalCFG), the compilation time of state-of-the-art code management technique [4] can be improved by an average of 5X, and that of stack management [20] can be improved by an average of 4X.
Energetics of two-ribbon solar flares

A theory of two-ribbon solar flares is presented which identifies the primary energy release site with the tops of the flare loops. The flare loops are formed by magnetic reconnection of a locally opened field configuration produced by the eruption of a pre-flare filament. Such eruptions are commonly observed about 15 min prior to the flare itself. It is proposed that the flare loops represent the primary energy release site even during the earliest phase of the flare, i.e., ‘the flare loops are in fact the flare itself’. Based upon the supposition that the energy release at the loop tops is in the form of Joulean dissipation of magnetic energy at the rising reconnection site, a quantitative model of the energy release process is developed based upon an analytic reconnecting magnetic field geometry believed to represent the basic process. Predicted curves of energy density vs time are compared with X-ray observations taken aboard Skylab for the events of 29 July, 13 August, and 21 August in 1973. Considering the crudity of the model, the comparisons appear reasonable. The predicted field strengths necessary to produce the observed energy density curves are also reasonable, being in the range 100–1000 G.
A high throughput in situ hybridization method to characterize mRNA expression patterns in the fetal mouse lower urogenital tract.

Development of the lower urogenital tract (LUT) is an intricate process. This complexity is evidenced during formation of the prostate from the fetal male urethra, which relies on androgenic signals and epithelial-mesenchymal interactions1,2. Understanding the molecular mechanisms responsible for prostate development may reveal growth mechanisms that are inappropriately reawakened later in life to give rise to prostate diseases such as benign prostatic hyperplasia and prostate cancer. The developing LUT is anatomically complex. By the time prostatic budding begins on 16.5 days post conception (dpc), numerous cell types are present. Vasculature, nerves and smooth muscle reside within the mesenchymal stroma3. This stroma surrounds a multilayered epithelium and gives rise to the fetal prostate through androgen receptor-dependent paracrine signals4. The identity of the stromal androgen receptor-responsive genes required for prostate development and the mechanism by which prostate ductal epithelium forms in response to these genes is not fully understood. The ability to precisely identify cell types and localize expression of specific factors within them is imperative to further understand prostate development. In situ hybridization (ISH) allows for localization of mRNAs within a tissue. Thus, this method can be used to identify pattern and timing of expression of signaling molecules and their receptors, thereby elucidating potential prostate developmental regulators. Here, we describe a high throughput ISH technique to identify mRNA expression patterns in the fetal mouse LUT using vibrating microtome-cut sections. This method offers several advantages over other ISH protocols. Performing ISH on thin sections adhered to a slide is technically difficult; cryosections frequently have poor structural quality while both cryosections and paraffin sections often result in weak signal resolution. Performing ISH on whole mount tissues can result in probe trapping. In contrast, our high throughput technique utilizes thick-cut sections that reveal detailed tissue architecture. Modified microfuge tubes allow easy handling of sections during the ISH procedure. A maximum of 4 mRNA transcripts can be screened from a single 17.5dpc LUT with up to 24 mRNA transcripts detected in a single run, thereby reducing cost and maximizing efficiency. This method allows multiple treatment groups to be processed identically and as a single unit, thereby removing any bias for interpreting data. Most pertinently for prostate researchers, this method provides a spatial and temporal location of low and high abundance mRNA transcripts in the fetal mouse urethra that gives rise to the prostate ductal network.
Infrared Time Domain Spectroscopy with Synchronized Frequency Combs

We describe a frequency-comb based system for time-domain spectroscopy in the near infrared. Our configuration implements synchronous, repetitive sampling of the time domain signature for real-time coherent signal averaging and improved signal-to-noise ratio.
Studying Strategy Effects on Memory, Attitudes, and Intentions

In this experiment, 175 participants generated node-link maps or summaries using multiple, massed, or ad lib schedules while reading text on stress-related information. They rated personal relevance immediately following studying and completed tests on the information and measures of attitudes and intentions 48 hours later. Low-verbal-ability participants who mapped and high-verbal-ability participants who summarized performed best on the tests and reported higher personal relevance. Multiple regression analyses indicated that personal relevance predicted test performance for those who mapped and was consistent in predicting both intentions to learn about and manage stress for all participants.
Human factor Xa bound amidine inhibitor conformation by double rotational-echo double resonance nuclear magnetic resonance and molecular dynamics simulations.

Double rotational-echo double resonance (double REDOR) NMR was used to investigate the conformation of a 13C-, 15N-, and 19F-labeled inhibitor (Berlex Biosciences compound no. ZK-806299) bound to h...
When a unit of insulin is not a unit: Detemir dosing and insulin cost in type 2 diabetes mellitus

Abstract Background: Increasing acceptance of basal-bolus insulin therapy for the control of diabetes mellitus (DM) has led to newer formulations of basal insulin analogues. The newest one is detemir. Objectives: Clinical evidence suggests that patients with type 2 DM require higher doses of detemir than other basal insulins to achieve equivalent glycemic control. This study examines evidence for greater dosing requirements and the implications of higher doses on the cost of insulin treatment. Methods: We performed a MEDLINE search for randomized, prospective studies comparing detemir with other basal insulins in patients with type 2 DM that were published in English between January 2000 and November 2008. The mean daily doses of basal and bolus insulin and the mean total daily insulin doses were determined. Overall weighted mean doses of the insulins were used to estimate the mean total daily insulin doses required for a 100-kg patient, and published 2008 US retail prices were used to estimate the retail costs of basal-bolus and basal-only insulin regimens. Results: Seven trials involving 3311 patients were identified in the literature search. The mean total daily insulin dose was 0.80 unit/kg for detemir-based regimens and 0.58 unit/kg for comparison regimens. For basal-bolus regimens, the estimated retail cost of the mean total daily insulin dose was $11.24 for detemir-based regimens compared with $8.99 for glargine-based regimens and $6.41 for neutral protamine Hagedorn (NPH)-based insulins. For basal-only regimens, the estimated retail cost of the mean total daily insulin dose was $8.23 for detemir compared with $5.19 for glargine and $2.35 for NPH. Conclusions: It is important for health care providers and patients to know that patients with type 2 DM may require substantially higher doses of detemir than other basal insulins. This should be considered when titrating the dose as well as in cost-benefit analyses of detemir versus other insulins.
One-dimensional nonseparating plane continua with disjoint ε-dense subcontinua

Abstract The following theorem is proved: suppose X is a one-dimensional nonseparating plane continuum such that for any e > 0, X has two disjoint e -dense subcontinua. Then X is either indecomposable or the union of two indecomposable continua. The result is used to address a question of Knaster.
Recent results on jet energy loss and direct photons at RHIC

Measurements of the π0 and direct photon nuclear modification factors in p+p and A+A collisions in the PHENIX experiment at RHIC will be reviewed and recent results at $\sqrt{S_{NN}}=62.4$ GeV will be presented. Using for the first time the p+p reference measured in the same experiment instead of averaging world data the π0 suppression turns out to be almost as large at $\sqrt{s_{NN}}=62.4$ GeV as at $\sqrt{s_{NN}}=200$ GeV, implying gluon densities dNg/dy>800. Possible origins of photon suppression at high pT in $\sqrt{s_{NN}}=200$ GeV are discussed in light of the new results on photon RAA at $\sqrt{s_{NN}}=62.4$ GeV.
Urban shrinkage as a performance of whiteness: neoliberal urban restructuring, education, and racial containment in the post-industrial, global niche city

Although Detroit is not a centre of global finance, and plays a declining role in global production, it nevertheless participates in the present remediation of the relationship between cities and the globe. Manoeuvring to reposition the city as the global hub of mobility technology, metropolitan Detroit's neoliberal leadership advances particular development strategies in urban education, housing, infrastructure, and governance, all with implications for social exclusion. This paper analyzes Detroit's neoliberal policy complex, uncovering how rituals of place-making and suburbanite nostalgia for the city intersect with broader struggles over the region's resources and representation.
Studies of near-barrier fusion induced by neutron-rich nuclei at HRIBF

Fusion induced by neutron-rich radioactive beams is a topic of current interest. The f ndings will be useful for using radioactive beams to produce superheavy elements. Results from recent measurements performed with neutron-rich radioactive Sn and Te beams are presented. Coupled-channels calculations were carried out to study the observed sub-barrier fusion enhancement. The fusion probability in Sn on Ni was probed by comparing the evaporation residue cross sections at high excitation energies.
Turbulence hits wall.

I wish to express my disappointment that Cipra's article could appear in Science. It is best described as extravagant advertising of unconfirmed ideas. Howlers such as measuring the slope of the deviation function instead of that of the log law of the wall and concluding that the classical theory is in error by 65% is something even my undergraduate students would find hard to believe.
Polio Eradication: Strengthening The Weakest Links

Polio eradication, like all eradication efforts, is a gamble. If it fails, much of the money spent will have been wasted. If it succeeds, the world will reap a dividend. Success or failure and the ...
A Statistical Framework for Assessment Using the ETS Major Field Test in Business

The Major Field Test in Business (MFT-B) is a widely used end-of-program assessment tool; however, several challenges arise when using the test in this capacity. Changing student demographics and the lack of a statistical framework are two of the most vexing issues confronting educators when using the MFT-B for programmatic assessment. The authors extended the literature by developing an analytical framework that controls for student demographics and provides statistically valid evidence of outcomes assessment. Application of the model to a sample data set revealed that the model fit well (R 2 = .517) and provides a valid framework for the exploration of outcomes assessment.
Early steps in assembly of the yeast vacuolar H+-ATPase.

Vacuolar proton-translocating ATPases are composed of a complex of integral membrane proteins, the Vo sector, attached to a complex of peripheral membrane proteins, the V1 sector. We have examined the early steps in biosynthesis of the yeast vacuolar ATPase by biosynthetically labeling wild-type and mutant cells for varied pulse and chase times and immunoprecipitating fully and partially assembled complexes under nondenaturing conditions. In wild-type cells, several V1 subunits and the 100-kDa Vo subunit associate within 3–5 min, followed by addition of other Vosubunits with time. Deletion mutants lacking single subunits of the enzyme show a variety of partial complexes, including both complexes that resemble intermediates in the assembly pathway of wild-type cells and independent V1 and Vo sectors that form without any apparent V1Vo subunit interaction. Two yeast sec mutants that show a temperature-conditional block in export from the endoplasmic reticulum accumulate a complex containing several V1 subunits and the 100-kDa Vo subunit during incubation at elevated temperature. This complex can assemble with the 17-kDa Vo subunit when the temperature block is reversed. We propose that assembly of the yeast V-ATPase can occur by two different pathways: a concerted assembly pathway involving early interactions between V1 and Vo subunits and an independent assembly pathway requiring full assembly of V1 and Vo sectors before combination of the two sectors. The data suggest that in wild-type cells, assembly occurs predominantly by the concerted assembly pathway, and V-ATPase complexes acquire the full complement of Vosubunits during or after exit from the endoplasmic reticulum.
Characteristics of systemic antibody responses of nonhuman primates following active immunization with Porphyromonas gingivalis, Prevotella intermedia and Bacteroides fragilis.

Periodontal disease is an infectious disease manifested by the progressive change of a healthy resident commensal microbiota to a pathogenic one characterized by a specific microbiota. Thus, the prospect for the use of selected bacteria or their antigens as a vaccine to interfere with the microbial changes and resulting progression of periodontal tissue destruction has been proposed. As a first step in examining the use of bacterial antigens as immunogens in periodontitis, this study characterized the humoral immune response in Macaca fascicularis after systemic immunization with intact Porphyromonas gingivalis, Prevotella intermedia and Bacteroides fragilis. Parenteral immunization of the nonhuman primate with the intact bacteria resulted in the production of specific and significantly elevated levels of antibodies to P. gingivalis and P. intermedia, with the predominant isotype being immunoglobulin G (IgG). In contrast, the principal response to the nonoral, intestinal bacterium, B. fragilis, was of the IgM isotype. Immunization increased IgG, IgM and IgA antibody by 14–227 fold to P. gingivalis and 8–108 fold to P. intermedia. The level of serum IgA antibody increased (77–227 fold). The kinetics of the antibody response post-immunization and post-ligation differed with respect to each of the bacteria tested. IgG antibody to P. gingivalis increased through week 16 of the experiment and remained elevated above baseline through week 32. The IgG antibody level to P. intermedia peaked at 4 weeks following the third immunization and decreased post-ligation to near baseline levels by week 16. Characterization of the immune response after active immunization in the nonhuman primate has demonstrated a substantial and specific increase in antibody response which was sustained for several weeks. The insights obtained from these studies should help optimize the potential for immunologic interference with progressing periodontitis.
Targeting prostate-specific membrane antigen in cancer therapy: can molecular medicine be brought to the surface?

Commentary to: Use of Methotrexate-Based Peptide Substrates to Characterize the Substrate Specificity of Prostate-Specific Membrane Antigen (PSMA)Annastasiah Mhaka, Alyssa M. Gady, D. Marc Rosen, Kin-Ming Lo, Steven D. Gillies and Samuel R. Denmeade
A stacked-patch reduced surface wave antenna

The reduced surface wave (RSW) microstrip antenna (Jackson, D.R. et al., IEEE Trans. Antennas and Propagat., vol.41, no.8, p.1026-37, 1993; Khayat, M.A. et al., IEEE Trans. Antennas and Propagat., vol.48, no.10, p.1581-93, 2000) is a modified annular-ring patch that has the inner boundary short-circuited to the ground (therefore it is called a "shorted annular-ring RSW", SAR-RSW, antenna). By appropriately choosing the outer radius, the dominant mode of the antenna excites no surface-wave fields. Consequently, RSW microstrip antennas launch very little surface-wave fields, and also have very little lateral (near-horizon) radiation. As a result, such antennas may be attractive for array applications, to reduce mutual coupling and scan blindness. However, the size of the RSW antenna introduced by Jackson et al. is fairly large. For a thin substrate, the diameter is about 0.6/spl lambda//sub 0/, and this does not change significantly with the substrate dielectric constant. For array and other applications, an RSW antenna of smaller size would be desirable. A new type of RSW microstrip antenna is proposed, to reduce the size. The antenna is a stacked-patch RSW antenna.
Modified shear lag model for fibers and fillers with irregular cross-sectional shapes

For fibers with irregular cross sections such as ultrahigh modulus polyethylene (UHMPE) fibers and ribbon-like carbon fibers, the original shear lag model would not provide accurate calculations for interfacial shear stress because it assumes a circular fiber cross section. In this study, a modified shear lag model is proposed to calculate the interfacial shear stress that reflects the change of fiber cross-sectional shape. Microbond test on a UHMPE fiber/epoxy system was used for verification of the model. The difference between the interfacial shear strength (IFSS) calculated using the modified model and that using the original model assuming an equivalent fiber diameter was found to be as high as 15% and it linearly increased as the irregularity of the cross-sectional shape increased. When the irregularity constant exceeds 1.12, the error in IFSS involved in using the original shear lag model and an equivalent fiber diameter is greater than 10%.
Endoplasmic Reticulum Stress Signaling in Pancreatic β-Cells

Pancreatic β-cells are specialized for the production and regulated secretion of insulin to control blood-glucose levels. Increasing evidence indicates that stress-signaling pathways emanating from the endoplasmic reticulum (ER) are important in the maintenance of β-cell homeostasis. Under physiological conditions, ER stress signaling has beneficial effects on β-cells. Timely and proper activation of ER stress signaling is crucial for generating the proper amount of insulin in proportion to the need for it. In contrast, chronic and strong activation of ER stress signaling has harmful effects, leading to β-cell dysfunction and death. Therefore, to dissect the molecular mechanisms of β-cell failure and death in diabetes, it is necessary to understand the complex network of ER stress-signaling pathways. This review focuses on the function of the ER stress-signaling network in pancreatic β-cells.
Beyond "Managed Change": Rethinking How Schools Improve.

ABSTRACT The following paper argues that existing model of change management in education are more appropriate for understanding small scale innovations than larger reforms. Results from two studies of schools engaged in major transformations are used to illustrate some of the differences between previous and current findings. A model of organizational learning as an alternative is presented, and some implications for both practice and theory in school improvement are discussed. 1. This paper was presented at the annual conference of the International Consortium for School Effectiveness and Improvement, Norkopping, Sweden, January 3‐6, 1993. An earlier version was presented at the International conference on School Restructuring sponsored by the Ontario Institute for Studies in Education, March 5‐7, 1992. Its preparation was supported by the Center for the Organization and Restructuring of Schools (U.S. Office of Education grant # R117Q00005‐9) at the University of Wisconsin. I am grateful for the contrib...
Stay-green ranking and maturity of corn hybrids: 1. Effects on dry matter yield, nutritional value, fermentation characteristics, and aerobic stability of silage hybrids in Florida

This study determined effects of maturity, stay-green (SG) ranking, and hybrid source on dry matter (DM) yield, nutritive value, fermentation, and aerobic stability of corn hybrids. One high stay-green (HSG) hybrid and one average stay-green (ASG) hybrid with similar relative maturity (117 d) from each of 2 seed companies (Croplan Genetics, St. Paul, MN; Pioneer Hi-Bred International, Des Moines, IA) were grown on 1-× 6-m plots at random locations within each of 4 blocks. The hybrids were harvested at 25, 32, and 37% DM from each plot and separated into thirds for botanical fractionation and analysis, whole-plant chemical analysis, and ensiling. Chopped, whole plants were ensiled (8 kg) in quadruplicate in 20-L mini-silos for 107 d. A split-plot design was used for the study. Yields of whole-plant and digestible DM and concentrations of starch and DM increased with maturity, whereas concentrations of crude protein, water-soluble carbohydrates, and neutral detergent fiber decreased. High SG hybrids had greater DM yield than ASG hybrids when harvested at 25 and 37%, but not 32% DM. Unlike those from Croplan Genetics, the Pioneer HSG hybrid had greater ear and whole-plant DM concentration than their ASG hybrids. Stover moisture and CP concentration were greater among HSG versus ASG hybrids, particularly among Croplan Genetics hybrids. Croplan Genetics HSG hybrids had greater neutral and acid detergent fiber concentrations and lower in vitro DM digestibility in the unensiled whole-plant, the stover, and the silage than their ASG hybrids, whereas contrasting trends were evident for Pioneer hybrids. Silage fermentation indices were largely unaffected by hybrid SG ranking, maturity, or source. Yeast counts increased with maturity and exceeded 10(5) cfu/g; therefore, all silages deteriorated with 26 h, irrespective of treatment. Among the hybrids examined, the optimal maturity for optimizing DM yield and nutritive value of the ASG and HSG hybrids was 37% DM. Stay-green ranking had maturity-dependent effects on the yield of hybrids but had varying effects on nutritional value depending on the source of the hybrid.
Using reinforcement learning to vary the m in GMRES(m)

Abstract While the original GMRES(m) iterative solver assumes the restart parameter m stays ﬁxed throughout the solve, in practic varying m can improve the convergence behavior of the solver. Previous work tried to take advantage of this fact by choosing the restart value at random for each outer iteration or by adaptively changing the restart value based on a measure of the progress made towards computing the solution in successive iterations. In this work a novel application of reinforcement learning to the problem of adaptively choosing values of m is described and then compared to the two existing strategies on matrices from a range of application areas.
Inhibition of vascular endothelial growth factor in the treatment of colorectal cancer

Angiogenesis is essential for tumor growth and metastasis and is a promising target in the search for new anti-neoplastic agents. Angiogenesis is a tightly regulated process dependent on the complex interplay between inhibitory and stimulatory angiogenic factors. Vascular endothelial growth factor is one of the best characterized of the pro-angiogenic growth factors, and multiple strategies have been developed to inhibit this pathway. Bevacizumab, a monoclonal antibody developed against vascular endothelial growth factor, has shown initial preclinical and clinical activity. This review will outline the conceptual basis of anti-angiogenic therapy, discuss the critical role of vascular endothelial growth factor, and summarize the available data on the use of bevacizumab in colorectal cancer.
Nucleation of chemically vapor deposited diamond on platinum and nickel substrates

Abstract Diamond growth on platinum and nickel substrates, both scratched and unscratched, was examined over a wide variety of growth conditions in an effort to understand the nucleation mechanism of diamond. The experiments used a combination of X-ray photoelectron spectroscopy, electron energy loss spectroscopy, and low energy electron diffraction to examine the time evolution of surface carbon species during diamond growth. Samples were transferred under vacuum from the filament-assisted diamond growth chamber to an attached ultrahigh vacuum analytical chamber. Our results indicate that diamond nucleates on platinum and nickel by pre-deposition of graphitic carbon precursors. Defect sites in these graphite deposits contain the nucleation sites for diamond. These nucleation sites are sensitive to the presence of gas phase oxygen species; therefore, addition of oxygen to the gas phase suppresses diamond nucleation by elimination of the nucleation sites but does not suppress growth of existing diamond. Our results demonstrate at least one mechanism whereby diamond can nucleate on metallic substrates such as platinum and nickel.
Analysis of the 300 and 600 MHz1H-NMR spectra of poly(3-vinyl thiopene)

The 300 and 600 MHz1H-NMR spectra of poly-(3-vinyl thiophene) synthesized via free radical initiated polymerization are presented and analyzed. The spectra are similar to those of poly-(2-vinyl thiophene) and were interpreted in a like manner. The polymer was found to be atactic with a Pm value of 0.48±.05.
Transcranial direct current stimulation (tDCS) reduces postsurgical opioid consumption in total knee arthroplasty (TKA)

Background Although pain is often a symptom that precedes total knee arthroplasty (TKA), the procedure itself is associated with considerable postoperative pain lasting days to weeks. Postoperative pain control is an important factor in determining recovery time, hospital length of stay, and rehabilitation success. Several brain stimulation technologies including transcranial direct current stimulation (tDCS) have demonstrated promise as treatments for a variety of pain conditions. The present study examined the effects of 4 sessions of tDCS on post-TKA pain and opioid consumption. Materials and methods Forty patients undergoing unilateral TKA were randomly assigned to receive a total of 80 minutes of real (n=20) or sham tDCS (n=20) with the anode over the knee representation of the motor strip (C1h or C2h corresponding to the target knee) and cathode over the right dorsolateral prefrontal cortex (F3; located by the EEG 10-20 System). Patient-controlled analgesia ( hydromorphone) use was tracked during the ∼48 hours postsurgery. Results Patients in the real tDCS group used an average of 6.6 mg (SD=5.3) of patient-controlled analgesia hydromorphone, whereas those in the sham group used 12.3 mg (SD=6.6; t37=2.93, P=0.006). Despite using less opioid medication, participants in the real tDCS group reported no pain exacerbation or worse mood with respect to those in the sham tDCS group. Conclusions Results from this pilot feasibility study suggest that tDCS may be able to reduce post-TKA opioid requirements. Although these results are preliminary, the data support further research in the area of adjunctive cortical stimulation in the management of postsurgical pain.
Confinement magnétique des réactions thermonucléaires

Quelques-unes des difficultes inherentes a la liberation d'energies de fusion elevees sont presentees. En particulier, le probleme du confinement d'un plasma thermonucleaire est etudie. On en deduit une methode qui permet de doubler l'efficience du champ magnetique de confinement. On discute aussi la rigueur et la valeur de l'approximation des investigations anterieures sur l'effet de pincement.
Spirits Captured in Stone: Shamanism and Traditional Medicine among the Taman of Borneo

Spirits Captured in Stone: Shamanism and Traditional Medicine among the Taman of Borneo. Jay Bernstein. Boulder, CO: Lynne Riener Publishers, Inc., 1997. xiv. 209 pp., figures, preface, notes, appendixes, bibliography, index.
Weight at menarche in deaf girls.

SummaryWeight at menarche of a mixed longitudinal sample of deaf American girls was analysed with regard to its variability and association with their earlier than normal age at menarche. The ‘critical weight’ hypothesis of Frisch and Revelle (1970, 1971) specifies the attainment of a certain body weight necessary for the onset of menstruation with a concomitant reduction in its variability. The findings herein suggest this hypothesis is not applicable to deaf girls.
Efficacy of intravenous immune globulin for treatment of experimental pseudomonas aeruginosa pneumonia

A human immunoglobulin G preparation, enriched in type-specific antibodies against Pseudomones aeruginosa lipopolysaccharide immunotypes 1, 2, 4, 6 (Fisher scheme), and suitable for intravenous infusion, has recently been developed. We evaluated the therapeutic efficacy of this preparation in a guinea pig model of P aeruginosa pneumonia. Intravenous infusion of 500 mg/kg of hyperimmune globulin into guinea pigs produced elevations in serum antibodies against P aeruginosa , which persisted for one week or longer. For study, animals were infected with type 1 or type 4 P aeruginosa challenge strains, then treated two hours after infection with a single intravenous infusion of 5% hyperimmune globulin (500 mg/kg), or 5% albumin. Cumulative survival rates for type 1 infection were 0/33 controls, and 12/36 globulin ( P P P aeruginosa immunoglobulin G preparation was more efficacious in treating pneumonia than was a conventional (nonhyperimmune) immunoglobulin G preparation. Finally, in experiments combining hyperimmune P aeruginosa globulin with tobramycin (1.7 mg/kg, six hours and 24 hours after infection), cumulative survivals from pneumonia were increased to 87%, as compared to survivals of 50% for tobramycin alone, 25% for globulin alone, and 0% in control groups. We conclude that passive immunization with a recently developed hyperimmune P aeruginosa immunoglobulin G preparation may be therapeutically useful in the management of life-threatening P aeruginosa pneumonia.
Activation Energies for Migration of K+ and N0 in KN3

Activation energies for the migration of K+ and N0 interstitials in KN3 crystals are calculated. The total cohesive energy is obtained from a modified Born model. Both double-spherical and triple-spherical potentials are used as the repulsive interaction. Polarization effects according to the Hatcher-Dienes scheme are employed. N0 interstitial migration is found to require very little energy and thus becomes a good candidate for explaining the explosive instability of the azides. Les energies d'activation pour la migration desions interstitiels K+ et N0 dans le KN3 ont ete calculees. L'energie totale de cohesion a ete obtenue a l'aide d'un modele de Born modifie. Des potentiels doublement-spheriques, ainsi que triplement-spheriques ont ete determines a l'aide d'un modele de Hatcher et Dienes. On a trouve que la migration de l'interstitiel N0 ne demande que peu d'energie, de sorte que ceci pourrait expliquer l'instabilite explosive des nitrures.
Varying whole body vibration amplitude differentially affects tendon and ligament structural and material properties.

Whole Body Vibration (WBV) is becoming increasingly popular for helping to maintain bone mass and strengthening muscle. Vibration regimens optimized for bone maintenance often operate at hypogravity levels ( 1 G) vibrations. The effect of vibratory loads on tendon and ligament properties is unclear though excessive vibrations may be injurious. Our objective was to evaluate how tendon gene expression and the mechanical/histological properties of tendon and ligament were affected in response to WBV in the following groups: no vibration, low vibration (0.3 G peak-to-peak), and high vibration (2 G peak-to-peak). Rats were vibrated for 20 min a day, 5 days a week, for 5 weeks. Upon sacrifice, the medial collateral ligament (MCL), patellar tendon (PT), and the Achilles Tendon (AT) were isolated with insertion sites intact. All tissues were tensile tested to determine structural and material properties or used for histology. Patellar tendon was also subjected to quantitative RT-PCR to evaluate expression of anabolic and catabolic genes. No differences in biomechanical data between the control and the low vibration groups were found. There was evidence of significant weakness in the MCL with high vibration, but no significant effect on the PT or AT. Histology of the MCL and PT showed a hypercellular tissue response and some fiber disorganization with high vibration. High vibration caused an increase in collagen expression and a trend for an increase in IGF-1 expression suggesting a potential anabolic response to prevent tendon overuse injury.
Stimulation of the Na+ pump by hypotonic solutions in skeletal muscle.

The fractional loss of 22Na+ from frog sartorius muscle is increased when the tonicity of the external solution is reduced. The effect, which is larger the lower the osmolarity, exhibits the following characteristics: (1) quick onset and reversibility, (2) is not reduced in the absence of external Na+, (3) is completely abolished by strophanthidin (3·10−5 M), (4) is neither the result of membrane depolarization nor K+ accumulation in the extracellular space.
A New Mesenchymal Stem Cell (MSC) Paradigm: Polarization into a Pro-Inflammatory MSC1 or an Immunosuppressive MSC2 Phenotype

Background Our laboratory and others reported that the stimulation of specific Toll-like receptors (TLRs) affects the immune modulating responses of human multipotent mesenchymal stromal cells (hMSCs). Toll-like receptors recognize “danger” signals, and their activation leads to profound cellular and systemic responses that mobilize innate and adaptive host immune cells. The danger signals that trigger TLRs are released following most tissue pathologies. Since danger signals recruit immune cells to sites of injury, we reasoned that hMSCs might be recruited in a similar way. Indeed, we found that hMSCs express several TLRs (e.g., TLR3 and TLR4), and that their migration, invasion, and secretion of immune modulating factors is drastically affected by specific TLR-agonist engagement. In particular, we noted diverse consequences on the hMSCs following stimulation of TLR3 when compared to TLR4 by our low-level, short-term TLR-priming protocol. Principal Findings Here we extend our studies on the effect on immune modulation by specific TLR-priming of hMSCs, and based on our findings, propose a new paradigm for hMSCs that takes its cue from the monocyte literature. Specifically, that hMSCs can be polarized by downstream TLR signaling into two homogenously acting phenotypes we classify here as MSC1 and MSC2. This concept came from our observations that TLR4-primed hMSCs, or MSC1, mostly elaborate pro-inflammatory mediators, while TLR3-primed hMSCs, or MSC2, express mostly immunosuppressive ones. Additionally, allogeneic co-cultures of TLR-primed MSCs with peripheral blood mononuclear cells (PBMCs) predictably lead to suppressed T-lymphocyte activation following MSC2 co-culture, and permissive T-lymphocyte activation in co-culture with MSC1. Significance Our study provides an explanation to some of the conflicting reports on the net effect of TLR stimulation and its downstream consequences on the immune modulating properties of stem cells. We further suggest that MSC polarization provides a convenient way to render these heterogeneous preparations of cells more uniform while introducing a new facet to study, as well as provides an important aspect to consider for the improvement of current stem cell-based therapies.
Ultrastructure and histogenesis of giant-cell tumor of bone.

An electron microscopic examination of tissue from a giant-cell tumor of bone revealed that the fine structure of the giant cells was indistinguishable from that of osteoclasts or of giant cells from other lesions. The giant cells appeared to form by fusion of mononucleated stromal cells and to increase in size and number of nuclei by merger with additional stromal cells. Giant cells did not show evidence of division and, therefore, could not be properly considered the principal tumor cell. Mononuclear stromal cells did divide, fulfilling a criterion of neoplasia, and are probably the main tumor cells. The resemblance of many stromal cells to macrophages, sinusoidal lining cells, and cells of lymphoid series suggested that the tumor may originate from these cells. An additional observation was the presence, in mitotically dividing cells, of paired and triple cisternae.
Transforming growth factor alpha gene expression in cultured human keratinocytes is unaffected by cellular aging

Background: Cultured human keratinocyte grafts have been shown to stimulate endogenous reepithelialization of both chronic nonhealing and acute partial-thickness wounds. This effect is most likely mediated by cytokines that stimulate keratinocyte growth, such as transforming growth factor alpha. The effect of cellular age on cytokine expression by cultured grafts used for this purpose is presently undefined. In this study, transforming growth factor alpha gene expression in cultured foreskin keratinocytes from donors varying in age from 2 to 82 years was analyzed semiquantitatively by two separate methods, ie, Northern hybridization and competitive polymerase chain reaction. Results: No pattern of decline in transforming growth factor alpha messenger RNA expression with increasing cellular age was observed by either analysis. Conclusion: The results indicate that expression of transforming growth factor alpha by cultured grafts may not be significantly affected by increasing cellular age and suggest that, even in the elderly, cultured autografts may be effective as pharmacologic agents for wound treatment. (Arch Dermatol. 1995;131:683-690)
Differentiation and gene regulation: Web alert

A selection of World Wide Web sites relevant to papers published in this issue of Current Opinion in Genetics & Development.
Physical models of the geospace radiation environment

Abstract A goal of predictive models of the space radiation environment is to provide advanced knowledge of significant variations in the highly energetic particle populations that form the Earth's radiation belts. The global geomagnetic field models that result from the Center for Integrated Space-weather Modeling (CISM) effort will provide a necessary input, a real-time description of the dynamic variation of the electromagnetic fields in the magnetosphere, for conducting detailed simulations of the radiation belts. In this work, we describe the issues and techniques that CISM will use to provide a physical space radiation model. An analysis of the global field configurations typical of the magneto hydrodynamic (MHD) models used in CISM suggest that much of the radiation belt modeling can proceed under a guiding center particle approximation, whereby individual, non-interacting test particles are used to track the aggregate dynamics of the radiation belts. This technique provides a relatively simple means of both conducting the necessary simulations, and coupling the relevant codes with other elements of the CISM project. The guiding center equations used to track the particles are based on a phase-space conserving approximation that conserves energy in regions of high curvature. Examples of test particle simulations with the MHD fields are given, both in the initial trapped particle population, and among the energetic particles that form the plasma sheet in the tail. These simulations suggest that multiple radiation belt models running simultaneously in the framework provided by CISM can be combined to provide an overall picture of the energetic particle environment. Finally, analysis of the spectral properties of the fields suggests how an alternate approach to modeling the global radiation belts, solution of the appropriate transport equations, might be advanced through the CISM effort.