cssi/SciSciGPT-SciSciNet huggingface dataset:
Sequence and overexpression of the menD gene from Escherichia coli.

Abstract The menD gene of Escherichia coli codes for the first enzyme of menaquinone biosynthesis, 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate (SHCHC) synthase. DNA sequence analysis of menD shows an open reading frame encoding a 52-kilodalton protein. Possible promoter and ribosome binding sites are present. Insertion of the menD gene into a tac promoter expression vector leads to nearly a 100-fold increase in the level of SHCHC synthase activity upon induction with isopropyl-beta-D-thiogalactoside (IPTG). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of [35S]methionine-labeled proteins shows a 61-kilodalton protein produced upon induction of the menD-containing expression vector. This is the first reported sequence analysis of a men gene and the first significant amplification of any of the menaquinone biosynthetic enzymes.
Testing classifiers for embedded health assessment

We present an example of unobtrusive, continuous monitoring in the home for the purpose of assessing early health changes. Sensors embedded in the environment capture activity patterns. Changes in the activity patterns are detected as potential signs of changing health. A simple alert algorithm has been implemented to generate health alerts to clinicians in a senior housing facility. Clinicians analyze each alert and provide a rating on the clinical relevance. These ratings are then used as ground truth in developing classifiers. Here, we present the methodology and results for two classification approaches using embedded sensor data and health alert ratings collected on 21 seniors over nine months. The results show similar performance for the two techniques, where one approach uses only domain knowledge and the second uses supervised learning for training.
Optical studies of charge dynamics in optimally doped Bi 2 Sr 2 CaCu 2 O 8 + δ

Systematic temperature-dependent optical studies of optimally doped ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$ (OP Bi2212) single crystals have been carried out. An electron-boson spectral function peaked at 43 meV is derived in the normal state at 100 K, indicating that the most significant spectral feature in OP Bi2212 is a resonance at 43 meV. The optical data below ${T}_{c}$ show that this boson is directly involved in the pair formation in OP Bi2212. Origins of the 43 meV mode are discussed.
Current developments in posterior composite resins.

The use of posterior composite resins has grown at a rapid rate. While the original materials were completely inadequate for the restoration of Class I and II cavity preparations, the newer-generation materials are apparently superior. While wear rates of over 100 μm per year were not uncommon, some of the newer composites wear away at the rate of less than 1 μm per month.A great deal of the improvement in wear resistance can be attributed to an optimization of the filler particle. Specifically, the particle size has been decreased and the filler loading has been increased. In some instances, softer filler particles have been incorporated in order to decrease the hardness differential between the filler and the resin matrix. Other factors which have been considered include chemical erosion of the matrix, degradation of the silane coupling agent, internal porosity, method of polymerization, and hydrophobicity of the resin matrix.A greater understanding has been developed regarding patterns of wear as well ...
The International Business Research Agenda: Recommendations from Marketing Practitioners.

ABSTRACT The authors surveyed professional members of the American Marketing Association who designated international marketing as a field of interest. The study measures which international business research topics marketing practitioners perceive to be of high utility or importance. In addition, the data reduction technique of factor analysis identified five latent factors (Global Market Expansion; International Marketing Management; Management Issues in an International Context; Quality, Values and Expectations; and Theoretical Considerations in International Business) which summarize the perceived research needs of the practitioner community. The findings offer insight into the international research topics of interest to professional marketers, thereby providing the academic marketing community with an additional source of input when determining future research agendas.
Plasticity and rigidity in adaptor protein-2-mediated internalization of the TCR:CD3 complex.

Many cell surface proteins are internalized via dileucine- or tyrosine-based motifs within their cytoplasmic domains by the heterotetrameric adaptor protein complex, AP-2. In this study we have examined how AP-2 mediates internalization of large cell surface receptors, such as the eight-chain TCR:CD3 complex. Although most receptors have a single signal that drives internalization, the TCR complex has two (D/E)xxxL(L/I) motifs and 20 YxxO motifs. Using 293T cells, we show that AP-2 is completely dependent on both signals to mediate TCR internalization, because deletion of either completely blocks this process. Significant plasticity and redundancy were observed in the use of the YxxO motifs, with a clear hierarchy in their use (CD3δ > CD3γ ≥ CD3ζ ≫ CD3e). Remarkably, a single, membrane-distal YxxO motif in CD3δ could mediate ∼75% of receptor internalization, whereas its removal only reduced internalization by ∼20%. In contrast, significant rigidity was observed in use of the (D/E)xxxL(L/I) motif in CD3γ. This was due to an absolute requirement for the position of this signal in the context of the TCR complex and for a highly conserved lysine residue, K128, which is not present in CD3δ. These contrasting requirements suggest a general principle by which AP-2 may mediate the internalization of large, multichain complexes.
A conceptual model of perceived customer value in e-commerce: A preliminary investigation

This article presents an exploratory study of a conceptual model of perceived customer value in a business-to-consumer e-commerce setting. Key precursors of perceived customer value included in the model are valence of on-line shopping experience, perceived product quality, perceived risk, and product price. Relationships among these variables (as well as mediating variables) and their relationship to on-line shoppers' value perceptions are explored. The theoretical framework proposed in this work expands on previous efforts on perceived customer value by including new variables relevant to an e-commerce setting and by integrating several key variables into one model. The preliminary findings lead to several implications. © 2003 Wiley Periodicals, Inc.
Polymorphisms of human TAP2 detected by denaturing gradient gel electrophoresis.

Abstract The human transporter associated with antigen processing ( TAP1 and TAP2 ) genes are located in the human leukocyte antigen (HLA) class II region of the genome and encode proteins that form a heterodimer essential for the transport of endogenous peptides into the endoplasmic reticulum for assembly with HLA class I molecules. Type 1 diabetes is an autoimmune disease that is associated with the HLA region of the genome, with HLA class II genes conferring the greatest statistical risk. The presentation of self-peptides by HLA class I molecules is defective in individuals with this disease, and both TAP1 and TAP2 are potential contributors to this defect. Denaturing gradient gel electrophoresis (DGGE) was applied to screen all 11 exons and the 3′ flanking region of TAP2 for polymorphisms in individuals with type 1 diabetes patients and controls. Seventy polymorphisms, including 51 in introns, 4 in the 3′ flanking region, and 15 in exons, were identified. Sequencing of polymorphic DNA fragments revealed several new polymorphisms, including a Gln → Arg substitution at codon 611 and a GT → GC polymorphism affecting the donor splice site of intron 4, that might be of functional significance. None of the polymorphisms examined differed in frequency between individuals with type 1 diabetes and controls.
Evaluation of Populus and Salix continuously irrigated with landfill leachate II. soils and early tree development.

Soil contaminant levels and early tree growth data are helpful for assessing phytoremediation systems. Populus (DN17, DN182, DN34, NM2, and NM6) and Salix (94003, 94012, S287, S566, and SX61) genotypes were irrigated with landfill leachate or municipal water and tested for differences in 1) element concentrations (P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, and Na) of a topsoil layer and a layer of sand in tanks with a cover crop of trees or no trees and 2) height, diameter, volume, and dry mass of leaves, stems, and roots. Trees were irrigated with leachate or water during the final 12 wk of the 18-wk study. Differences in most soil element concentrations were negligible (P > 0.05) for irrigation treatments and cover main effects. Phosphorous, K, Mg, S, Zn, Mn, Fe, and Al concentrations were greater in topsoil than sand (P = 0.0011 for Mg; P < 0.0001 for others). There was broad variation between genera and among clones for all growth traits. The treatment × clone interaction governed height, volume, and roo...
The fatty acid composition of sphingolipids from bovine CNS axons and myelin.

— Cerebrosides, sulphatides and sphingomyelin were isolated from bovine CNS myelin and from myelin-free axons derived from myelinated axons. The fatty acid composition of each sphingolipid was determined by gas-liquid chromatography of the fatty acid methyl esters. In each case the fatty acids of the axonal sphingolipids were of shorter average chain length than those from the corresponding myelin lipids. These differences, however, were small and the fatty acids of the axonal cerebrosides and sulphatides were similar in average chain length to those reported previously for bovine myelin. The principal unsubstituted acid of both cerebroside and sulphatide from axons was 24: 1, with the total long chain acids (> C18) amounting to 80 and 85 per cent, respectively. The corresponding figures for myelin galactolipids were 94 and 95 per cent long chain acids. The principal α-hydroxy acid of both axonal galactolipids was 24 h:0, with cerebroside having 80 per cent and sulphatide 92 per cent long chain acids, compared to the figures of 87 and 97 per cent for the corresponding myelin lipids. In axonal sphingomyelin the major acid was 18:0 (compared to 24:1 in myelin) and the long chain acids were 61 per cent of the total vs 76 per cent of the total for myelin sphingomyelin. The non-identity of axonal and myelin sphingolipid fatty acids substantiates the belief that they are intrinsic axonal constituents. These findings do not rule out the possibility of a close metabolic relationship between the sphingolipids of the axon and its myelin sheath.
Surface characterization of recycled tire rubber to be used in cement paste matrix.

Abstract The surface modification of tire rubber after treatment with saturated NaOH aqueous solution was investigated by HATR infrared analysis, potentiometric titration, and contact angle measurements. Infrared analysis of the powdered treated rubber showed a decrease in absorption at 1540, 1450, and 1395 cm −1 . This decrease is attributed to the removal of zinc stearate, an additive present in tire formulations that often migrates and diffuses to the surface, resulting in poor adhesion between the rubber and other materials. The potentiometric titration of the suspension of powdered rubber in 0.1 M NaCl showed that more hydrochloric acid was consumed by the untreated rubber, most likely a result of the hyrdrolysis of the zinc stearate to the organic acid. Contact angles of flat tire pieces showed an homogeneity enhancement of the treated rubber surface. The decrease of the zinc stearate on the treated rubber surface explains the improvement in the adhesion of this material to the cement matrix, observed in a previous research. The promising results of this study are a starting point for future research on incorporating rubber particles into cementitious materials as a means of successfully utilizing the vast amounts of tire waste currently in landfills.
Intimate partner violence among men prevalence, chronicity, and health effects.

Context The breadth and depth of intimate partner violence (IPV) experienced by men have not been fully documented. Objectives To describe the prevalence, chronicity, and severity of IPV, and the health outcomes associated with IPV, in adult men with healthcare insurance. Design A retrospective telephone cohort study conducted from 2003 to 2005. The setting was an integrated healthcare system in Washington State and Idaho. Participants English-speaking men aged 18 and older (N=420) enrolled in the healthcare system for 3 or more years. Main Outcome Measures Physical, psychological, and sexual IPV were assessed using five questions from the Behavioral Risk Factor Surveillance Survey. Health was measured using the Short Form-36, version 2 (SF-36v2) survey, the Center for Epidemiological Studies Depression Scale, and the National Institute of Mental Health Presence of Symptoms Survey. Results Men experienced IPV at a rate of 4.6% in the past year, 10.4% in the past 5 years, and 28.8% over their lifetimes. While overall rates of physical and nonphysical IPV were similar, men aged 18–55 were twice as likely to be recently abused (14.2%, SE=2.6%) than were men aged 55 and older (5.3%, SE=1.6%). Abuse was typically nonviolent or mildly violent, occurred on multiple occasions, and was initiated by only one intimate partner. Compared to men with no IPV, older men who experienced IPV had more depressive symptoms (prevalence ratios=2.61 and 2.80 for nonphysical and physical abuse) and had lower SF-36v2 mental health subscales (range=−3.21 to −5.86). Conclusions Men experience IPV at moderate rates, and poor mental health outcomes are associated with such experiences.
The energy-release rate and “self-force” of dynamically expanding spherical and plane inclusion boundaries with dilatational eigenstrain

Abstract In the context of the linear theory of elasticity with eigenstrains, the radiated field including inertia effects of a spherical inclusion with dilatational eigenstrain radially expanding is obtained on the basis of the dynamic Green's function, and one of the half-space inclusion boundary (with dilatational eigenstrain) moving from rest in general subsonic motion is obtained by a limiting process from the spherically expanding inclusion as the radius tends to infinity while the eigenstrain remains constrained, and this is the minimum energy solution. The global energy-release rate required to move the plane inclusion boundary and to create an incremental region of eigenstrain is defined analogously to the one for moving cracks and dislocations and represents the mechanical rate of work needed to be provide for the expansion of the inclusion. The calculated value, which is the “self-force” of the expanding inclusion, has a static component plus a dynamic one depending only on the current value of the velocity, while in the case of the spherical boundary, there is an additional contribution accounting for the jump in the strain at the farthest part at the back of the inclusion having the time to reach the front boundary, thus making the dynamic “self-force” history dependent.
The influence of isotacticity, ethylene comonomer content, and nucleating agent additions on the structure and properties of melt‐spun isotactic polypropylene filaments

The influence of isotacticity, ethylene comonomer content, and nucleating agent additions on the structure and properties of melt-spun polypropylene filaments was studied for a series of polypropylenes having similar resin melt flow rates (MFR ≃ 35), average molecular weights, and polydispersities. In general, increasing the degree of isotacticity increases crystallinity and tensile modulus of the spun filaments, while increasing the copolymer content has the opposite effect. Nucleating agent additions also lead to greater crystallinity, but, under certain conditions, the addition of a nucleating agent can lead to lower tensile modulus in spite of higher crystallinity. For given spinning conditions, the tensile strength increased slightly with increased copolymer content but was little affected by tacticity in the range studied. Nucleating agent additions lowered the tensile strength of spun filaments. The effects of nucleating agents on the filament modulus and tensile strength were traced to their ability to raise the crystallization temperature and reduce the level of molecular orientation generated in the filaments. The reasons for the observed behavior are discussed.
In vitro studies of the wear of articular cartilage—III. The wear characteristics of chemically modified articular cartilage when worn against a highly polished characterized stainless steel surface

Abstract The wear characteristics of chemically modified articular cartilage, when worn against a smooth stainless steel plate whose surface profile was characterized, were studied. The chemical modifications consisted of extracting some constituents of the tissue with aqueous solutions of either 2 M CaCl 2 , 3 M MgCl 2 , or 0.5 M EDTA at pH 7.4, or digesting it to various extents with either trypsin or testicular hyaluronidase. Samples of cartilage, subjected to the various procedures, were characterized for their hydroxyproline, hexosamine, and total protein contents, their amino acid compositions, their calcium and magnesium contents and their swelling ratios in equilibrium with 0.03 M Tris -HCl at pH 7.4 at 4°C. In addition, the fluid and hexosamine contents of trypsin digested cartilage were measured as a function of depth. As with normal cartilage, the tissue initially wore at higher rates than that finally attained at each pressure. After a period of time, characteristic for each treatment, the tissue wore at a constant, steady state rate (except for the case where the tissue was subjected to digestion with trypsin for 18 hr at 37°C). The constant wear rates of cartilage digested with trypsin were considerably higher than those of normal cartilage when worn under the same pressure. Hyaluronidase digested cartilage, however, wore at similar steady state rates as normal tissue despite the fact that it had much lower glycosaminoglycan contents. Cartilage equilibrated with 2 M CaCl 2 at 4° and 37°C, with 3 M MgCl 2 or 0.5 M EDTA at 4°C wore at markedly reduced rates. Furthermore the wear-time curves of these samples were different from those of normal or enzymatically digested cartilage. The relative values of the average steady state wear rates of each group of samples were found to have a qualitative correlation with their swelling ratio in equilibrium with Tris buffer, at neutral pH, except cartilage that was extracted with 0.5 M EDTA. The data are interpreted to indicate that the constant wear rates under these conditions decrease with increasing average crosslink or interaction densities between the macromolecular species of the matrix. Our results further suggest that calcium and to a lesser extent magnesium act to crosslink the matrix of the tissue by forming complexes with donor ligands from its constituents.
Characterization of TMPRSS2:ETV5 and SLC45A3:ETV5 Gene Fusions in Prostate Cancer

Recurrent gene fusions involving oncogenic ETS transcription factors (including ERG, ETV1, and ETV4) have been identified in a large fraction of prostate cancers. The most common fusions contain the 5′ untranslated region of TMPRSS2 fused to ERG. Recently, we identified additional 5′ partners in ETV1 fusions, including TMPRSS2, SLC45A3, HERV-K_22q11.23, C15ORF21, and HNRPA2B1. Here, we identify ETV5 as the fourth ETS family member involved in recurrent gene rearrangements in prostate cancer. Characterization of two cases with ETV5 outlier expression by RNA ligase–mediated rapid amplification of cDNA ends identified one case with a TMPRSS2:ETV5 fusion and one case with a SLC45A3:ETV5 fusion. We confirmed the presence of these fusions by quantitative PCR and fluorescence in situ hybridization. In vitro recapitulation of ETV5 overexpression induced invasion in RWPE cells, a benign immortalized prostatic epithelial cell line. Expression profiling and an integrative molecular concepts analysis of RWPE-ETV5 cells also revealed the induction of an invasive transcriptional program, consistent with ERG and ETV1 overexpression in RWPE cells, emphasizing the functional redundancy of ETS rearrangements. Together, our results suggest that the family of 5′ partners previously identified in ETV1 gene fusions can fuse with other ETS family members, suggesting numerous rare gene fusion permutations in prostate cancer. [Cancer Res 2008;68(1):73–80]
Effect of atorvastatin on blood lipid levels in the first 2 weeks of treatment: a randomized, placebo-controlled study.

Abstract Background The rate and degree of LDL cholesterol reduction, in the first 2 weeks of therapy, may relate to the early benefit of hydroxymethyl glutaryl coenzyme A reductase inhibitor therapy. In patients with similar baseline LDL cholesterol levels as in the Cholesterol and Recurrent Events (CARE) trial, we report the results of a 2-week placebo-controlled, double-blind investigation of 10 mg/day atorvastatin. Methods and Results The 22 participants were non-Hispanic whites younger than age 72 (average age 47 years) who were modestly overweight and had normal blood pressure. There were no significant baseline lipid and lipoprotein differences. By day 5, there were significant ( P P P Conclusion The rapid lipid reduction observed with atorvastatin may benefit the vascular endothelium. (Am Heart J 2000;140:249-52.)
Emotion in psychogenic nonepileptic seizures: Responses to affective pictures

We examined emotional responses to standard affective pictures in 18 psychogenic nonepileptic seizure (PNES) patients. Given reports of trauma and posttraumatic stress symptoms (PTS) in many PNES patients, comparison groups were seizure-free individuals high and low in PTS (PTS-high, PTS-low; n=18 per group). Patients with psychogenic nonepileptic seizures (1) reported more emotional intensity to neutral and pleasant pictures than PTS-low and more intensity to neutral pictures than PTS-high, and (2) showed less positive emotional behavior to pleasant pictures than PTS-high. Groups did not differ in pleasantness/unpleasantness ratings, negative emotional behavior, cardiac interbeat interval, or respiratory sinus arrhythmia (RSA) reactivity to the pictures. Patients with psychogenic nonepileptic seizures reported more general emotion regulation difficulties and showed lower baseline RSA than PTS-low but not PTS-high. In sum, intense emotional experience and diminished positive emotional behavior characterized PNES patients' emotional responses.
Aripiprazole in Children with Attention-Deficit/Hyperactivity Disorder

Abstract Objective: To examine the effectiveness and cognitive effects of aripiprazole (APZ) in children with a primary diagnosis of attention-deficit/hyperactivity disorder (ADHD). Methods: Youths, ages 8–12 years, with a diagnosis of ADHD combined-type or ADHD predominately inattentive-type were enrolled into a 6-week, open-label pilot trial. Outcome measures included the ADHD Rating Scale-IV (ARS-IV), Clinical Global Impressions Scale (CGI), and Children's Global Assessment Scale (CGAS). The Conners' Continuous Performance Test II, Reading and Math Fluency subscales of the Woodcock-Johnson III Tests of Achievement, and the Stroop Color and Word Test were administered at baseline and end of study. Results: Fourteen (9 males and 5 females) youths were diagnosed with ADHD-combined type, while 9 (5 males and 4 females) were diagnosed with ADHD-inattentive type. At a mean dose of 6.7 mg/day, end of study results showed overall significant improvement from baseline on ADHD and functional outcome measures. No...
The influence of thyroxine and thiouracil on rats fed excess tyrosine.

SummaryAddition of thiouracil to a high tyrosine diet alleviated signs of tyrosine toxicity in the rat, whereas, daily injections of thyroxine aggravated them. Plasma tyrosine concentration and liver tyrosine transaminase activity were high in rats fed a high tyrosine diet; thyroxine administration increased them further, but depressed slightly the activity of liver p-hydroxyphenylpyruvate hydroxylase.
Sol-gel synthesis of thin films of potassium titanyl phosphate for non-linear optical applications

Report of a new sol-gel route for preparing thin film KTP. Continuous, uniform and transparent films were obtained with grain sizes of about 0.3μm. Sol-gel derived KTP films were found to exhibit waveguiding
Introduction of Living Polymerization. Living and/or Controlled Polymerization

The effects of various imperfections such as slow initiation, termination, transfer and slow exchange on kinetics, molecular weights and polydispersities in chain growth polymerizations are simulated. The simukations demonstrate that well defined polymers polymers can be prepared in systems with chain-breaking reactions. Thus, under carefully selected conditions, non-living polyumerizations may provide controlled polymers. On the other hand, polymers with unpredictable molecular weights and broad and even polymodal molecular weight distributions can be formed in living systems without irreversible transfer and termination. In some living systems molecular weights may stay constant or even decrease with conversion. Therefore, a clear distrinction should be made between living and polymerizations.
Study of crack-tip motion in dynamic fracture by microscopic time-resolved holography

A novel laser system has been designed and developed for the time-resolved holographic analysis of dynamic crack propagation in thin (150 μm) glass plates. The system provides a frame-to-frame resolution of from 28.3 to 161.6 ns, with a spatial resolution of better than 25 μm. Holographic analyses were conducted using both diffuse and direct laser illumination, demonstrating a broad range of applicability for this method. A series of specimens with pre-crack lengths of from 3.5 to 10.5 mm were tested using various pre-load levels and crack-growth-initiating explosive sizes. All specimens exhibited similar dynamic fracture behavior, particularly those outside of the region of shock of the initiating explosive (those of the longer pre-crack set). A best-fit to the theoretical prediction for mode I crack growth revealed a good match to the case for a specimen ‘overloaded’ by 64 percent. However, no variation with applied load was evident, indicating that an immediate acceleration to a velocity of ≈ 1200 m/s (near the empirically determined terminal velocity) was the more plausible fit. Since the terminal velocity was approximately the same for all specimens, this investigation also demonstrated that the terminal velocity is independent of crack-tip stresses, even for the most extreme explosive pulses.
Artistic explorations of the brain.

The symbiotic relationships between art and the brain begin with the obvious fact that brain mechanisms underlie the creation and appreciation of art. Conversely, many spectacular images of neural structures have remarkable aesthetic appeal. But beyond its fascinating forms, the many functions performed by brain mechanisms provide a profound subject for aesthetic exploration. Complex interactions in the tangled neural networks in our brain miraculously generate coherent behavior and cognition. Neuroscientists tackle these phenomena with specialized methodologies that limit the scope of exposition and are comprehensible to an initiated minority. Artists can perform an end run around this impasse by representing the brain’s many functions in a manner that can communicate to a wide and receptive audience. This paper explores the ways that brain mechanisms can provide a largely untapped subject for artistic exploration.
Measures of threading specificity and accuracy.

Threading predictions for CASP2 target proteins were compared to their true structures using a series of precisely defined measures of agreement, calculated in a fully automatic way. Fold recognition specificity was calculated as the proportion of a predictor's “bet” that was placed on previously-known structures similar to the prediction target, as identified by a “jury” of well-tested structure–structure comparison methods. Values approaching 100% indicate that a prediction correctly identified the structural and/or evolutionary family to which a target belongs. Alignment specificity was calculated as the proportion of aligned residue pairs in the predicted target-to-known-structure alignment that also occur in the structure–structure alignments produced by the “jury” methods. Contact specificity was calculated as the proportion of nonlocal residue contacts in the molecular model implied by threading alignment, that also occur in the experimental structure of the target. Alignment specificity and contact specificity measure the accuracy of a predicted 3-dimensional model. Values approaching 100% indicate that target residues have been assigned to the correct spatial locations and that the model is as accurate as possible for a threading prediction. Proteins, Suppl. 1:74–82, 1997. © 1998 Wiley-Liss, Inc.
Spectral Phosphorus Mapping using Diffuse Reflectance of Soils and Grass

Phosphorus (P) concentration was determined from reflectance spectra of grass and soils in a total of 150 samples of each collected from three different sites in the Lake Okeechobee drainage basin. The reflectance spectra of both fresh and dried samples for grass and soil were measured in the ultraviolet (UV), visible (VIS), and near infrared (NIR) regions from 225 to 2550 nm with an interval of 1 nm. Phosphorus concentrations of the samples were correlated with the absorbance of the same samples. Two-thirds of both vegetation and soil samples were used for calibration and the remaining one-third of vegetation and soils were used for validation. Stepwise multiple linear regressions (SMLR), and partial least-squares (PLS) analyses were applied to the data sets in order to predict P concentrations for soil and grass. Actual and predicted P concentration maps of the fields for vegetation and soil were plotted. Strong relationships (coefficient of determination R 2 = 0 · 778 , 0·914, and 0·922) in PLS for the validation data sets were obtained between absorbance and P concentrations in soils. However, a weak relationship ( R 2 = 0 · 425 ) in PLS for the validation data set was produced from absorbance and P concentrations in vegetation samples. Spatial variation in actual and predicted maps showed that P variability could be represented using diffuse reflectance spectroscopy in the UV, VIS, and NIR regions.
Phenylglyoxal modification of the Photosystem II reaction center

Abstract Time-resolved spectroscopic techniques, including optical flash photolysis and electron spin resonance (ESR), have been used in conjunction with fluorescence-induction and dye-reduction assays to monitor electron transport in Photosystem II (PS II) subchloroplast particles incubated with the covalent modifier, phenylglyoxal. Phenylglyoxal-modified digitonin (D-10) particles from spinach are characterized by (1) a high initial fluorescence yield ( F i ) and an abolition of the variable component of fluorescence ( F v ); (2) an inhibition of PS-II-mediated reduction of dichlorophenol indophenol (DPIP) by sym -diphenylcarbazide; (3) an abolition of flash-induced absorption transients ( t 1 2 > 2 μ s ) at 820 nm attributed to the primary electron donor, P-680 + ; (4) the inhibition of photoreduction of the acceptor Q a ; and (5) the elimination of the ESR Signal 2 s and Signal 2 f . These observations suggest the critical participation of specific arginine residues on both the oxidizing and reducing sides of Photosystem II and also implicate phenylglyoxal as a quinone-binding site inhibitor (Golbeck, J.H. and Warden, J.T. (1984) Biochim. Biophys. Acta 767, 263–271).
Insurgent Expertise: The Politics of Free/Livre and Open Source Software in Brazil

ABSTRACT Under the administration of President Luiz Inacio Lula da Silva, the Brazilian state has advocated the use of Free/Livre and Open Source Software (FLOSS) throughout the public sector. How did FLOSS adoption gain traction as a developmental strategy across a large federal bureaucracy that had embraced information technology policies supporting export-oriented growth and market liberalization during the 1990s? In a historical case study, I argue that the FLOSS agenda emerged as a result of the actions of a network of insurgent experts working within elite political, technical, and educational institutions. I trace the history of this mobilization and show how a dedicated network of experts brought about conditions for institutional transformation that contradicted prevailing neoliberal policy proscriptions. The Brazilian FLOSS insurgency offers insights into the means by which a group of elites endeavored to reframe debates about technology-driven economic growth around questions of state-led acces...
Making Sense of the New Cervical-Cancer Screening Guidelines

In the past 2 years, four major U.S. health care organizations have issued new guidelines on cervical-cancer screening. Although there are differences among them, all agree on some points, including that screening shouldn't begin before age 21 in immunocompetent women.
Identification of binding sites in the nicotinic acetylcholine receptor for [3H] azietomidate, a photoactivatable general anesthetic

To identify binding domains in a ligand-gated ion channel for etomidate, an intravenous general anesthetic, we photolabeled nicotinic acetylcholine receptor (nAChR)-rich membranes from Torpedo electric organ with a photoactivatable analog, [(3)H]azietomidate. Based upon the inhibition of binding of the noncompetitive antagonist [(3)H]phencyclidine, azietomidate and etomidate bind with 10-fold higher affinity to nAChRs in the desensitized state (IC(50) = 70 microm) than in the closed channel state. In addition, both drugs between 0.1 and 1 mm produced a concentration-dependent enhancement of [(3)H]ACh equilibrium binding affinity, but they inhibited binding at higher concentrations. UV irradiation resulted in preferential [(3)H]azietomidate photoincorporation into the nAChR alpha and delta subunits. Photolabeled amino acids in both subunits were identified in the ion channel domain and in the ACh binding sites by Edman degradation. Within the nAChR ion channel in the desensitized state, there was labeling of alphaGlu-262 and deltaGln-276 at the extracellular end and deltaSer-258 and deltaSer-262 toward the cytoplasmic end. Within the acetylcholine binding sites, [(3)H]azietomidate photolabeled alphaTyr-93, alphaTyr-190, and alphaTyr-198 in the site at the alpha-gamma interface and deltaAsp-59 (but not the homologous position, gammaGlu-57). Increasing [(3)H]azietomidate concentration from 1.8 to 150 microm increased the efficiency of incorporation into amino acids within the ion channel by 10-fold and in the ACh sites by 100-fold, consistent with higher affinity binding within the ion channel. The state dependence and subunit selectivity of [(3)H]azietomidate photolabeling are discussed in terms of the structures of the nAChR transmembrane and extracellular domains.
Spectral evidence for stirring scales and two-dimensional turbulence in the auroral ionosphere

Electric field power spectra from two auroral sounding rocket flights show evidence of a distinct scale size regime for injection of energy into the auroral oval. The signature of this process is a broad plateau in the spectrum, with power law dependences at both shorter and longer scale sizes. We argue that the spectral properties at high k are dominated by processes occurring near the edges of inverted-V electron precipitation regions (auroral arcs). We see no compelling reason to conclude that a linear local plasma instability is occurring but rather, that nonlinear mixing and forward cascade yield the observed velocity field. The spectra of simultaneously observed density irregularities are quite different from those of the electric field, implying that the plasma density does not behave as a passive scalar in the auroral zone during active conditions. At low-k values we show that the rocket spectra are consistent with the power spectra of magnetospheric electric fields measured by the DE, AE-C, and Hilat stallites.
Salamanders in forest-floor food webs: Invertebrate species composition influences top–down effects

Summary The red-backed salamander, Plethodon cinereus, is an abundant predator in northeastern North America, where it is hypothesized to play an important role in the regulation of forest-floor invertebrate communities. We tested the hypothesis that the top–down effects of P. cinereus are influenced by the species composition of invertebrates of the forest-floor. In a month-long microcosm experiment, we compared salamander effects on invertebrate species composition in leaf-litter from two sites that differed in species and size composition of invertebrate detritivores (an urban forest site at which isopods and millipedes were numerous and a rural forest site at which Collembola were the most numerous detritivores, but isopods and millipedes were few). Our results were consistent with our initial hypothesis. The presence of salamanders within microcosms was associated with decreased densities of oribatid mites, pseudoscorpions, isopods and millipedes in comparison to salamander-absent controls, but negative effects of salamanders on isopods and millipedes were most strongly expressed within urban litter microcosms. Salamanders were also associated with a positive, indirect effect, i.e., an increase in density of podomorphic Collembola in comparison to salamander-absent controls, but within urban litter exclusively. Our results suggested that plethodontid salamanders exerted positive, indirect effects through consumption of an intermediate predator, i.e., pseudoscorpions, and macroinvertebrate competitors, i.e., isopods and millipedes, of podomorphic Collembola. We hypothesize that differences in salamander-mediated dynamics between the two litter sources resulted from prey selection by P. cinereus based on differences in prey size and abundance between the rural and urban forest litter.
Mass spectrometric characterization of amino sugar aldononitrile acetate derivatives used for isotope enrichment assessment of microbial residues

Abstract Identifying the transformation of amino sugars in soils is essential in understanding microbial contribution to soil organic matter turnover and sequestration. Using a recently developed method, combining gas chromatograph/mass spectrometry (GC/MS) with laboratory incubation of substrates containing 13 C or 15 N isotopes, we were able to trace isotopic changes in amino sugar compounds. This allows us to quantitatively evaluate C or N enrichment in amino sugars during transformation in soils using the fragment ( F ) abundance ratio of m / z F + n to F ( n is original skeleton atom number in each fragment). However, there is still lack of detail structural and substitutional information for each ion fragment. In order to improve the interpretation and increase our ability to study amino sugar turnover, we grew labeled amino sugars in lab-cultured organisms. We spectrometrically investigated the ion structures and original skeleton C number (mass shift n ) in major ion fragments based on applying multiple representative isotope labels. Our results categorically confirm that previously made assumptions were correct regarding the substitutional number “ n ” of the glucosamine ( He et al., 2006 ). Our study also added valuable structural information for aldononitrile acetate derivatized glucosamine and muramic acid upon electron impact ionization in MS.
Validated risk stratification model accurately predicts low risk in patients with unstable angina

Abstract BACKGROUND In the mid 1990s, two unstable angina risk prediction models were proposed but neither has been validated on separate population or compared. OBJECTIVES The purpose of this study was to compare patient outcome among high, medium and low risk unstable angina patients defined by the Agency for Health Care Policy and Research (AHCPR) guideline to similar risk groups defined by a validated model from our institution (RUSH). METHODS Four hundred sixteen patients consecutively admitted to the hospital with unstable angina between January 1, 1995, and December 31, 1997, were prospectively evaluated for risk factors. The presence of major adverse events such as myocardial infarction (MI), death and heart failure was assessed for each patient by chart review. RESULTS The composite end point of heart failure, MI or death occurred in 3% and 5% of the RUSH and AHCPR low risk categories, respectively, and in 8% and 10% of AHCPR and RUSH high risk categories, respectively. Recurrent ischemic events were best predicted by the RUSH model (high: 24% vs medium: 12% and low: 10%, p = 0.029), but not by the AHCPR model (high: 14% vs medium: 13% and low: 9%, p = 0.876). The RUSH model identified five times more low risk patients than the AHCPR model. CONCLUSIONS Both models identify patients with low and high event rates of MI, death or heart failure. However, the RUSH model allowed for five times more patients to be candidates for outpatient evaluation (low risk) with a similar observed event rate to the AHCPR model; also, the RUSH model more successfully predicted ischemic complications. We conclude that the RUSH model can be used clinically to identify patients for early noninvasive evaluation, thereby improving cost effectiveness of care.
Mathematical model for the frequency of radiation carcinogenesis at low doses

Abstract It is pointed out that the observed effect-function dependence on the dose is predicted theoretically by an additive superposition of 1-cell and N-cell contributions. This is illustrated quantitatively by solving an idealized mathematical model in which the 1-cell and N-cell effect-probabilities are postulated to have very simple statistical forms.
Identification of histidylleucine and other histidyl peptides as normal constituents of human urine

Abstract In order to examine the possibility that the urinary excretion of histidylleucine might reflect the in vivo biogenesis of angiotensin, a technique has been devised for the detection of histidyl peptides in normal human urine. The peptides are isolated by displacement procedures on ion-exchange resins and further analyzed by paper and ion-exchange column chromatography. Histidyl peptides have been quantitated by fluorescence analysis after reaction with o-phthalaldehyde. Histidylleucine, in quantities of about 5–25 μg, has been shown to be present in 24-hour collections of human urine. The peptide isolated from urine has been found to be identical with synthetic material in comparisons using high resolution ion-exchange chromatography, paper chromatography in four solvent systems, acid hydrolysis followed by amino acid analysis, and fluorescence spectrum. A histidyl peptide which was regularly present, usually in somewhat larger quantities, was a tripeptide with sequence His-Leu-Gly or His-Gly-Leu. Numerous other histidyl peptides were present in smaller amounts but did not correspond to any of several other simple histidyl dipeptides examined and were not further identified.
Far-infrared and submillimeter observations of the multiple cores in S255, W3, and OMC-1 - Evidence for fragmentation?

The two cores of the S255 cloud were mapped at 60, 100, 185, and 400 microns and 40-400 microns maps were made of the cores and S255, OMC-1 and W3. Absolute flux densities were determined with an accuracy of 30 percent. The luminosities and masses of the S255 cores were equivalent to those of the other objects, including the concentration of a compact H II region around young objects. The densified regions are regarded as typical of areas where massive objects are forming. The observed 1.4-4 km/sec velocity differences between two cores in any one cloud indicates that the angular momentum of the original clouds, which drove the collapse of the cores, is transferred to the massive young stars.
Effects of Naltrexone and Ro 15‐4513 on a Multiple Schedule of Ethanol and Tang Self‐Administration

Background: Both the opioid antagonist, naltrexone, and GABAA/benzodiazepine-site negative modulator, Ro 15-4513, decrease ethanol self-administration in rodents and nonhuman primates. However, the selectivity of these drugs for decreasing ethanol self-administration relative to reducing responding maintained by other reinforcers in primates is not clear. The present study used a multiple schedule self-administration procedure in cynomolgus monkeys to examine the selectivity of naltrexone and Ro 15-4513 for reducing ethanol self-administration relative to an orange flavored sugar-free sweetened solution (Sugar-free Tang). Methods: Six adult cynomolgus monkeys were trained to self-administer 4% (w/v) ethanol and 4% or 6% (w/v) Tang under a multiple schedule of liquid access. The effect of acute administration of naltrexone (0.1, 0.3, 1, 3 mg/kg) was examined. The effect of 15 days of chronic, 1 mg/kg naltrexone on ethanol and Tang self-administration was then examined in four monkeys. Acute administration of Ro 15-4513 (0.01, 0.03, 0.1, 0.3 mg/kg) as well as 15 days of chronic administration of 0.1 mg/kg Ro 15-4513 was also examined in four monkeys. Results: Ethanol and Tang were self-administered at similar volumes and patterns under baseline conditions. Acute naltrexone administration significantly decreased total session ethanol and Tang intake as well as the number and volume of ethanol and Tang drinks. Chronic naltrexone also significantly decreased ethanol and Tang intake. Ethanol, but not Tang, drink volume was significantly decreased by chronic 1 mg/kg naltrexone pretreatment. The number of ethanol and Tang drinks and drink duration were not significantly decreased by chronic naltrexone. Acute Ro 15-4513 pretreatment significantly decreased ethanol and Tang intake, mean drinks and median drink duration. Chronic 0.1 mg/kg Ro 15-4513 pretreatment significantly decreased total ethanol intake only during the first week of pretreatment, but it significantly decreased Tang intake for all 3 pretreatment weeks. Conclusions: Similar to rodent studies, acute and chronic naltrexone and Ro 15-4513 reduced ethanol and Tang intake in cynomolgus monkeys. However, unlike rodent studies, neither drug showed selectivity for reducing ethanol intake compared with a comparison reinforcer. These differences highlight the need for testing putative ethanol abuse treatment drugs under diverse conditions and multiple species before undertaking human clinical trials.
IMPACT OF THE MARS CURRICULUM : THE MASS UNIT

The Model-based Analysis and Reasoning in Science (MARS) project is involved in developing model-centered curriculum modules for middle-school science. MARS instruction focuses on a variety of physical, pictorial, and symbolic representations of theoretical entities, providing tangible objects that students can use to think and talk about abstract concepts and links between concepts. This article examines the impact of the mass unit, the third unit of a sixth-grade curriculum module, implemented in a public school during the 1993–1994 school year. Following an overview of the unit itself, three sections describe its impact as revealed by three aspects of evaluation: (1) classroom observations of opportunities to learn afforded students through instructional activities and interactions; (2) examination of students' written work, including worksheets and free-response test performance; and (3) analysis of protocol data from individual interviews conducted at the end of each of the three main sections of the curriculum. The article concludes with a discussion of specific implications for the MARS curriculum and general implications for science instruction. © 1998 John Wiley & Sons, Inc. Sci Ed82:53–91, 1998.