cssi/SciSciGPT-SciSciNet huggingface dataset:
Exploring the Relationship Among ADHD, Stimulants, and Substance Abuse

TOPIC: There is an ongoing debate among prescribers concerning the risk of inadvertently contributing to the initiation of substance abuse (SA) in children and adolescents through the use of stimulants in the treatment of attention-deficit/hyperactivity disorder (ADHD). Psychiatric nurses at all levels of practice must be informed about this important discourse in order to provide accurate and timely interventions to clients and their families. PURPOSE: This literature review explores the current state of prescriptive stimulant use for ADHD and the possible links to SA. Developmental, genetic, and neuro-chemical theories of the disorder that may contribute to SA as well as the burden of comorbidity are considered. The impact of gender, cultural, legal, and ethical influences on diagnostic and treatment recommendations is also included. SOURCE: U.S. and other English language articles were identified through PubMed and the Cumulated Index of Nursing and Allied Health Literature. These sources were used to determine the current practice of stimulant prescription and the prevalence of SA as a comorbidity to other child psychiatric disorders including ADHD. Textbooks were consulted for information regarding relevant neurochemistry, genetics, and psychopharmacology. CONCLUSIONS: The authors conclude that the use of stimulants is appropriate for children and adolescents with ADHD when opportunities for screening, family and child education, and counseling concerning SA are consistently integrated into the ongoing treatment regimen.
Electrodynamic Displacement of Atomic Energy Levels. I. Hyperfine Structure

The vacuum fluctuations of the photon and pair fields modify the interaction of an electron with an electromagnetic field. The effects on the energy levels are conveniently described in terms of the mass operator and the vacuum polarization potential. A gauge-covariant expansion of the mass operator for the motion of an electron in a weak external electromagnetic field is derived; the expression contains terms quadratic in the field but includes only the lowest order electrodynamic correction. The modification in the Fermi formula is then computed by specializing the external field to consist of the Coulomb and magnetic dipole fields of the nucleus and by taking the matrix element of the operators in an $S$-state of a hydrogen-like atom. All changes can be described as a correction $\ensuremath{\Delta}g=\ensuremath{-}2Z{\ensuremath{\alpha}}^{2}(\frac{5}{2}\ensuremath{-}\mathrm{ln}2)$ in the gyromagnetic ratio of the electron. The value of the fine structure constant deduced from measurements of the hyperfine structure becomes ${\ensuremath{\alpha}}^{\ensuremath{-}1}=137.0364$.
Differential Foliar Sensitivity of Soybean Cultivars to Ozone Associated with Differential Enzyme Activities

Soybean [Glycine max (L.) Merr.] cultivars Dare and Hood were exposed to ozone (980 μg/m3) for 2 h to determine if differences in cultivar sensitivity were associated with differential activation of selected enzymes. The first trifoliate leaves of the cultivars were in similar stages of development (14 days from sowing) when exposed. The ozone treatment increased the activities of glucose 6-phosphate dehydrogenase, phenylalanine ammonia lyase, polyphenol oxidase and peroxidase above the control in both cultivars within 30 h after exposure. However, the activity of all these enzymes increased several hours sooner in Dare (sensitive) than in Hood (tolerant). Our data suggest that the differential sensitivity of these two cultivars to ozone could be based on the differential ozone induced activation of the enzymes involved in the lesion formation process.
A Meta-Analysis on Gender Differences in Mental Rotation Ability Measured by the Purdue Spatial Visualization Tests: Visualization of Rotations (PSVT:R)

This meta-analysis was conducted to estimate the magnitude of gender difference in three-dimensional (3-D) mental rotation ability and to investigate how factors related to test administration conditions play a role in varying gender difference effect sizes and threatening validity. Individuals’ 3-D mental rotation ability was measured by the Purdue Spatial Visualization Tests: Visualization of Rotations (PSVT:R). We integrated 70 effect sizes of gender differences in mental rotation ability measured by the PSVT:R which were obtained from 40 primary studies. The results indicated that male participants outperformed females on the test (Hedges’ g = 0.57). The I 2 statistic indicated 41.7 % of variation in effect sizes reflects real heterogeneity. The moderator analysis indicated that male superiority on spatial ability tasks measured by the PSVT:R is related to the implementation of time limits. The gender difference became larger when stringent time limits (equal or less than 30 s per item) were implemented.
ACP Journal Club. Immunochemical FOBT was accurate for detecting colorectal cancer but less so for other GI lesions

Source Citation Chiang TH, Lee YC, Tu CH, Chiu HM, Wu MS. Performance of the immunochemical fecal occult blood test in predicting lesions in the lower gastrointestinal tract. CMAJ. 2011;183:1474-81...
Transformation behavior of TRIP steels

True-stress (σ), true-strain (e) and volume fraction martensite(f) were measured during both uniform and localized flow as a function of temperature on TRIP steels in both the solution-treated and warm-rolled conditions. The transformation curves(f vs e) of materials in both conditions have a sigmoidal shape at temperatures above Msσ (maximum temperature at which transformation is induced by elastic stress) but approach initially linear behavior at temperatures below Msσ where the flow is controlled by transformation plasticity. The martensite which forms spontaneously on cooling or by stress-assisted transformation below Msσ exhibits a plate morphology. Additional martensite units produced by strain-induced nucleation at shear-band intersections become important above Msσ. Comparison of σ-e andf-e curves indicate that a “rule of mixtures” relation based on the “static” strengthening effect of the transformation product describes the plastic flow behavior reasonably well above Msσ, but there is also a dynamic “transformation softening” contribution which becomes dominant below Msσ due to the operation of transformation plasticity as a deformation mechanism. Temperature sensitivity of the transformation kinetics and associated flow behavior is greatest above Msσ. Less temperature-sensitive TRIP steels could be obtained by designing alloys to operate with optimum mechanical properties below Msσ.
Subsumption of program entities for efficient coverage and monitoring

Program entities such as branches, def-use pairs, and call sequences are used in diverse software-development tasks. Reducing a set of entities to a small representative subset through subsumption saves monitoring overhead, focuses the developer's attention, and provides insights into the complexity of a program. Previous work has solved this problem for entities of the same type, and only for some types. In this paper we introduce a novel and general approach for subsumption of entities of any type based on predicate conditions. We discuss applications of this technique, and address future steps.
Parallel visual computation

The functional abilities and parallel architecture of the human visual system are a rich source of ideas about visual processing. Any visual task that we can perform quickly and effortlessly is likely to have a computational solution using a parallel algorithm. Recently, several such parallel algorithms have been found that exploit information implicit in an image to compute intrinsic properties of surfaces, such as surface orientation, reflectance and depth. These algorithms require a computational architecture that has similarities to that of visual cortex in primates.
Use of ultrasound in neurosurgical operations: a preliminary report.

Abstract Real-time ultrasound scanning has considerable potential in the neurosurgical operating room for the localization and further characterization of intracranial lesions as well as for planning and guiding the approach to such lesions. With further refinements, the ultrasound scanner may well be considered a surgical instrument and become a valued part of the neurosurgical armamentarium.
Modification of azo dyes by lactic acid bacteria.

Aim: The ability of Lactobacillus casei and Lactobacillus paracasei to modify the azo dye, tartrazine, was recently documented as the result of the investigation on red coloured spoilage in acidified cucumbers. Fourteen other lactic acid bacteria (LAB) were screened for their capability to modify the food colouring tartrazine and other azo dyes of relevance for the textile industry. Methods and Results: Most LAB modified tartrazine under anaerobic conditions, but not under aerobic conditions in modified chemically defined media. Microbial growth was not affected by the presence of the azo dyes in the culture medium. The product of the tartrazine modification by LAB was identified as a molecule 111 daltons larger than its precursor by liquid chromatography-mass spectrometry. This product had a purple colour under aerobic conditions and was colourless under anaerobic conditions. It absorbed light at 361 and 553 nm. Conclusion: LAB are capable of anabolizing azo dyes only under anaerobic conditions. Impact and Significance of the Study: Although micro-organisms capable of reducing the azo bond on multiple dyes have been known for decades, this is the first report of anabolism of azo dyes by food related micro-organisms, such as LAB.
A rapid method to screen fungi for resistance to toxic chemicals

Although many species of fungi are able to degrade highly toxic chemicals, only a few species have been evaluated for resistance to toxic effects of these chemicals. In this paper we demonstrate the successful application of a method to rapidly screen several species of fungi for toxicity to chemicals or mixtures of chemicals using pentachlorophenol (PCP) as a model toxic compound. Cellulose antibiotic assay disks were soaked in solutions containing different concentrations of PCP (5, 10, 25, 50, and 80 mg l−1) and then placed in a triangular pattern outside the growing edge of the mycelia of eighteen species of white rot fungi. The plates were incubated and observed for development of inhibition zones (non-growth areas) around the disks. The short-term (24 h) growth of all eighteen species of fungi was inhibited by 5–10 mg-PCP l−1, a range similar to that observed using previously reported techniques. Long-term growth studies using this screening method were not useful since PCP diffused from the disk into the agar, decreasing the applied dose.
Evidence for two sites of inhibition of photosynthetic electron transport by dibromothymoquinone.

Two sites in the photosynthetic electron transport chain of spinach chloroplasts are sensitive to inhibition by the plastoquinone antagonist dibromothymoquinone (2,5-dibromo3-methyl-&isopropyl-p-benzoquinone). This compound imposes maximal inhibition on reactions involving electron transport from water to a terminal acceptor such as ferricyanide at concentrations of about 1 PM. At concentrations of about 10 PM, dibromothymoquinone also inhibits electron transport reactions catalyzed by photosystem II in the presence of pphenylenediimines or p-benzoquinones. This inhibition is observed in both untreated and KCN/Hg-inhibited chloroplast preparations. Thiol incubation of chloroplasts exposed to dibromothymoquinone relieves inhibition at both sites. This reversal of inhibition is, however, different for the two sites. Restoration of ferricyanide reduction, which is blocked by 1 pM dibromothymoquinone, required high thiol/inhibitor ratios and incubation times with thiol of up to 3 min. The reversal of inhibition of p-phenylenediimine reduction by photosystem II, on the other hand, requires a thiol/inhibitor ratio of 1, and incubation times as short as 5 s. Addition of bovine serum albumin to absorb dibromothymoquinone results in a partial restoration of photosystem II reactions, but ferricyanide reduction, which requires photosystem II and photosystem I, cannot be restored by this procedure.
Linear and semilikear eigenvalue problems in Rn

We consider the problem for , with respect to the existence and asymptotic behavior of solutions as For the linear, radially symmetric problem with , the number of zeros and asymptotic behavior of the solutions is known as λ> 0 varies. In this paper we study the linear equation as well as bounded and sublinear perturbations of the linear equation. For the nonsyrnmetric, linear and semilinear equations we investigate the structure of the set of X for which the solutions are positive and decay to zero. Unlike the symmetric linear case, these results cannot be derived directly from the fundamental structure theorem for linear ordinary differential equations. We work with topological methods and comparison theorems.
De novo truncating FUS gene mutation as a cause of sporadic amyotrophic lateral sclerosis

Mutations in the gene encoding fused in sarcoma (FUS) were recently identified as a novel cause of amyotrophic lateral sclerosis (ALS), emphasizing the genetic heterogeneity of ALS. We sequenced the genes encoding superoxide dismutase (SOD1), TAR DNA-binding protein 43 (TARDBP) and FUS in 99 sporadic and 17 familial ALS patients ascertained at Mayo Clinic. We identified two novel mutations in FUS in two out of 99 (2.0%) sporadic ALS patients and established the de novo occurrence of one FUS mutation. In familial patients, we identified three (17.6%) SOD1 mutations, while FUS and TARDBP mutations were excluded. The de novo FUS mutation (g.10747A>G; IVS13-2A>G) affects the splice-acceptor site of FUS intron 13 and was shown to induce skipping of FUS exon 14 leading to the C-terminal truncation of FUS (p.G466VfsX14). Subcellular localization studies showed a dramatic increase in the cytoplasmic localization of FUS and a reduction of normal nuclear expression in cells transfected with truncated compared to wild-type FUS. We further identified a novel in-frame insertion/deletion mutation in FUS exon 12 (p.S402_P411delinsGGGG) which is predicted to expand a conserved poly-glycine motif. Our findings extend the mutation spectrum in FUS leading to ALS and describe the first de novo mutation in FUS.
Length and Sequence Heterogeneity in the Mitochondrial Internal Transcribed Spacer of Acanthamoeba spp.

The internal transcribed spacer (ITS) between the mitochondrial large (23S rRNA; rnl) and small (16S rRNA; rns) subunit ribosomal RNA genes of Acanthamoeba castellanii strain Neff was sequenced previously and was uniquely interesting because it contained tRNA genes with acceptor stem mismatches that underwent RNA editing repair. Our interest in this ITS region was to determine its phylogenetic potential in differentiating between closely related isolates. We analyzed the mitochondrial ITS region for 17 Acanthamoeba isolates and observed extensive sequence and length variability, making this region difficult to align. Acanthamoeba griffini strain S-7 had the shortest ITS (i.e. 559 base pairs [bp]) compared with Acanthamoeba palestinensis strain Reich, which had the longest (i.e. 1,360 bp). The length disparity occurred predominantly between the spacer region of the aspartic acid (trnD) and methionine (trnM) tRNA genes. Unexpectedly, this region in A. palestinensis Reich was found to contain a duplication of the trnM gene. Additionally, like A. castellanii strain Neff, all isolates examined had tRNAs with mismatches in their acceptor stem. Also, the potential for an additional type of editing not described previously for Acanthamoeba, involving purine to pyrimidine transversions was observed.
Studies of density distributions in one-dimensional shock-induced debris clouds

Abstract The vaporization of target and projectile materials in hypervelocity impact events is known to substantially influence target interaction effects. In this paper, two experimental techniques are presented for studying shock-induced vaporization for one-dimensional motion. One uses velocity interferometry to measure the motion history produced when a one-dimensional vapor cloud stagnates against a laser window. The other employs fast radiography to measure the density distributions in one-dimensional vapor clouds. Data obtained for shock-induced vaporization in lead and cadmium with these techniques have been compared to computer simulations, which indicate (1) good agreement for small amounts of vapor and for small propagation distances and (2) increasing disagreement as the degree of vaporization increases. These results suggest that either diffusing flow between the vapor and liquid phases occurs under these conditions, or that vaporization kinetics are important.
Isolation amd partial characterization of the most immunologically reactive antigen from mycobacterium tuberculosis h37ra culture filtrate

Summary The culture filtrate of Mycobacterium tuberculosis H37Ra was fractionated by ammonium sulphate precipitation, diethyl aminoethyl (DEAE) cellulose-Sephadex A-50 column chromatography, preparative isoelectic focusing and polyacrylamide gal electrophoresis to isolate the most antigenic tuberculoprotein. One protein, designated P2, was isolated and determined by immunodiffusion to be the most immunologically reactive antigen present in H37Ra culture filtrate. This protein had a molecular weight of about 22 000, a sedimentation constant of 2.2S and was present in Seibert's A, B, and C proteins.
Attenuation of ischemia-induced activation of cardiac sympathetic afferents following brief myocardial ischemia in cats

Objective: We have previously shown that brief myocardial ischemia impairs neural conduction in cardiac sympathetic efferent fibers. However, attenuation of the activity of afferent sympathetic nerves, which may contribute to impaired ischemic nociception and reflex hemodynamic responses, is not well understood. Therefore, we studied the electrophysiological effects of brief myocardial ischemia on the mechano-, chemo- and ischemia-sensitive properties of cardiac sympathetic afferent fibers. Methods: Single unit activity of sympathetic afferent Aδ and C fibers innervating the left ventricle (LV) was recorded from the thoracic chain or rami communicantes in 16 anesthetized cats. We tested the response of impulse activity to (1) mechanical LV probing, (2) epicardial application of bradykinin (10 μg), H2O2 (1.5%) or adenosine (500 μg), and (3) 1 min of coronary occlusion. Repeat tests were performed in 11 of 16 fibers after 15 min of coronary occlusion and 15 min of reperfusion. Control responses were measured in five fibers before and after a 30-min interval without ischemia. Results: Afferent fibers responded with increased activity to LV probing (16/16 fibers), bradykinin (13/16 fibers), H2O2 (7/11 fibers), adenosine (1/11 fibers), and to a 60 s period of coronary occlusion (11/16 fibers). The unit impulse activity to 1 min of coronary occlusion was markedly attenuated after 15 min of myocardial ischemia and 15 min of reperfusion (P<0.05). This attenuation was associated with reduced sensitivity to mechanical and chemical stimuli, while in separate time-control studies (n=5) no attenuation was observed in absence of ischemia. Conclusion: A brief period of myocardial ischemia is capable of attenuating mechano-, chemo- and ischemia-sensitive activity of cardiac afferent sympathetic nerves. This may have important implications for the mechanism of silent myocardial ischemia.
A study of MER-29 in experimental animals.

Summary MER-29 was cyaluated in three species: the Cebus monkey, the obese-hyperglycemic strain of mouse, and the capon. The serum cholesterol was lowered in the monkey and mouse but not in the espon. Studies of the appearance and disappearance of labeled sterols from the sera of Cebus monkeys injected with radio-mevalonate during the control and MER-29 treatment period were presented.
Full-scale thrust reverser testing in an altitude facility

A two-dimensional convergent-divergent exhaust nozzle designed and fabricated by Pratt and Whitney Aircraft was installed on a PW1128 turbofan engine and tested during thrust reverser operation in an altitude facility at NASA Lewis Research Center. A unique collection system was used to capture the thrust reverser exhaust gas and transport it to the primary exhaust collector. Tests were conducted at three flight conditions with varying amounts of thrust reverse at each condition. Some reverser exhaust gas spillage by the collection system was encountered but engine performance was unaffected at all flight conditions tested. Based on the results of this test program, the feasibility of altitude testing of advanced multi-function exhaust nozzle systems has been demonstrated.
The Human Medium Chain Acyl-CoA Dehydrogenase Gene Promoter Consists of a Complex Arrangement of Nuclear Receptor Response Elements and Sp1 Binding Sites

Expression of the gene encoding the mitochondrial fatty acid. beta-oxidation enzyme, medium-chain acyl-CoA dehydrogenase (MCAD), is regulated among tissues during development and in response to alterations in substrate availability. To identify and characterize cis-acting MCAD gene promoter regulatory elements and corresponding transcription factors, DNA-protein binding studies and mammalian cell transfection analyses were performed with hjman MCAD gene promoter fragments. DNA:protein binding studies with nuclear protein extracts prepared from hepatoma G2 cells, 3T3 fibroblasts, or Y-1 adrenal tumor cells identified three sequences (nuclear receptor response element 1 or NRRE-1, NRRE-2, and NRRE-3) that bind orphan members of the steroid/thyroid nuclear receptor superfamily including chicken ovalbumin upstream promoter transcription factor and steroidogenic factor 1. Sp1 binding sites (A-C) were identified in close proximity to each of the NRREs. NRRE-3 conferred cell line-specific transcriptional repression by interacting with chicken ovalbumin upstream promoter transcription factor or activation via steroidogenic factor 1. In contrast, the Sp1 binding site A behaved as a transcriptional activator in all cell lines examined. We propose that multiple nuclear receptor transcription factors interact with MCAD gene promoter elements to differentially regulate transcription among a variety of cell types.
Diagnostic Accuracy of Pattern Electroretinogram Optimized for Glaucoma Detection

Purpose To assess the ability of the new pattern electroretinogram optimized for glaucoma detection (PERGLA) paradigm to discriminate between healthy individuals and individuals with glaucomatous optic neuropathy (GON). Design Cross-sectional study. Participants One hundred forty-two eyes of 71 participants (42 healthy and 29 with GON in at least 1 eye) enrolled in the University of California, San Diego, Diagnostic Innovations in Glaucoma Study were studied. Healthy individuals were those recruited as healthy with healthy-appearing optic disc by examination and masked stereoscopic optic disc photograph evaluation. Glaucomatous optic neuropathy was defined based on stereophotograph evaluation. Methods The PERGLA (Glaid Elettronica, Pisa, Italy) recordings were obtained within 6 months of standard automated perimetry (SAP) testing. Dependent variables were PERGLA amplitude, phase, amplitude asymmetry, phase asymmetry, and SAP pattern standard deviation (PSD) and mean deviation (MD). Main Outcome Measures Diagnostic accuracy (sensitivity and specificity) of the PERGLA normative database for classifying healthy and glaucomatous individuals was determined. In addition, performance (areas under receiver operating characteristic curves [AUCs]) of PERGLA amplitude and phase for classifying healthy (n = 84) and GON (n = 50) eyes was determined. Results from both analyses were compared with those from SAP. Results Sensitivity and specificity of the PERGLA normative database were 0.76 and 0.59, respectively, compared with 0.83 and 0.77 for SAP. The AUCs for PERGLA amplitude and phase were 0.75 and 0.50 (chance performance), respectively. The AUCs for SAP PSD and MD were 0.83 and 0.78, respectively. Conclusions Pattern electroretinograms recorded using the PERGLA paradigm can discriminate between healthy and glaucoma eyes, although this technique performed no better than SAP at this task. Low specificity of the PERGLA normative database suggests that the distribution of recordings included in the database is not ideal. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.
Characterization of MOCVD PbTiO3 thin films

Abstract The metal-organic chemical vapor deposition (MOCVD) technique has excellent potential for the deposition of device-quality ferroelectric thin films. The MOCVD method has been applied to the preparation of perovskite PbTiO3 thin films on fused silica and Pt-coated alumina substrates. An MOCVD system has been designed and built to deposit PbTiO3 films starting from organic precursors (tetraethyl lead and titanium isopropoxide). A wide range of conditions were investigated, and the conditions suitable for the deposition of perovskite PbTiO3 were identified. The stoichiometry of the PbTiO3 films as determined by electron microprobe analysis was variable over a wide range, and two types of microstructures, either faceted or nodular were produced. When prepared under appropriate deposition conditions, the MOCVD PbTiO3 films exhibited nominally phase-pure perovskite XRD patterns. However, the lattice parameters calculated by x-ray diffraction (a = 3.91 and c = 4.09 angstroms) indicated a slightly lesser...
Association Between Treatment or Usual Care Region and Hospitalization for Fall-Related Traumatic Brain Injury in the Connecticut Collaboration for Fall Prevention

OBJECTIVES: To evaluate the association between the treatment region (TR) or usual care region (UCR) of the Connecticut Collaboration for Fall Prevention (CCFP), a clinical intervention for prevention of falls, and the rate of hospitalization for fall-related traumatic brain injury (FR-TBI) in persons aged 70 and older and to describe the Medicare charges for FR-TBI hospitalizations. DESIGN: Using a quasi-experimental design, rates of hospitalization for FR-TBI were recorded over an 8-year period (2000-2007) in two distinct geographic regions (TR and UCR) chosen for their similarity in characteristics associated with occurrence of falls. SETTING: Two geographical regions in Connecticut. PARTICIPANTS: More than 200,000 persons aged 70 and older. INTERVENTION: Clinicians in the TR translated research protocols from the Yale Frailty and Injuries: Cooperative Studies of Intervention Techniques, a successful fall-prevention randomized clinical trial, into discipline- and site-specific fall-prevention procedures for integration into their clinical practices. MEASUREMENTS: Rate of hospitalization for FR-TBI in persons aged 70 and older. RESULTS: Connecticut Collaboration for Fall Prevention's TR exhibited lower rates of hospitalization for FR-TBI than the UCR (risk ratio = 0.84, 95% credible interval = 0.72-0.99). CONCLUSION: The significantly lower rate of hospitalization for FR-TBI in CCFP's TR suggests that the engagement of practicing clinicians in the implementation of evidence-based fall-prevention practices may reduce hospitalizations for FR-TBI. Language: en
A compatibility equation for nonequilibrium ionization

Compatibility equation for calculation of electron temperature, plasma electric conductivity and electric field profiles
Extraction and analysis of trifluoroacetic Acid in environmental waters

Trifluoroacetic acid (TFA), a mildly phytotoxic compound, is a stable atmospheric breakdown product of HFC-134a, HCFC-123, and HCFC-124. An extraction and analytical method has been developed for the routine analysis of low ppt levels of TFA in aqueous samples. TFA can be quantitatively recovered from most environmental waters by an extraction procedure using a commercial anion-exchange disk. In saline samples (conductivity >620 μS), where the presence of competing anions interfered with recovery, a liquid-liquid extraction cleanup was necessary. After extraction of TFA from water, the dried disk was placed in a headspace vial containing 10% sulfuric acid in methanol and the vial sealed and then vortexed for 30 s. The sulfuric acid-methanol solution extracts trifluoroacetate anion (TFA) from the anion-exchange matrix and, when heated, quantitatively converts it to the methyl ester, which is then analyzed by automated headspace gas chromatography using electron capture or mass spectrometry detection. Several environmental samples in addition to laboratory spike solutions were successfully extracted and analyzed with this technique. Recoveries averaged 108.2% for reagent water spiked at levels from 53 to 2110 ng/L with relative standard deviations ranging from 0.3 to 8.4%. The instrument's limit of detection for TFA standard was 3.3 ng. The limit of quantitation for the extraction and analytical technique was 36 ng/L. Three water samples can be prepared for automated analysis in 20 min using this technique.
Adsorption of Chloroform in NaY Zeolite: A Computational and Vibrational Spectroscopy Study

The structure and energetics of chloroform binding sites in NaY zeolite have been studied by energy-minimization calculations and vibrational spectroscopy. A new force field for chlorocarbon-type molecules in zeolites has been developed. Our simulations predict the adsorption of chloroform in the 12-ring window where the hydrogen atom is involved in a hydrogen bond with the framework oxygens. This interaction is clearly revealed by inelastic neutron scattering and Raman spectroscopies, which show a typical softening of the stretching mode (ν1) and a hardening of the bending mode (ν4) involving the H atom of the adsorbed chloroform molecule. The overall host−guest interaction energy involves three components that have been identified as being typical of hydrohalocarbon adsorption in zeolites: (i) short-range interactions between chlorine and framework oxygens, (ii) electrostatic interactions between chlorine atoms and accessible Na ions, and (iii) hydrogen bonding with the framework oxygens.
Transport and Kinetics in Sandwiched Membrane Bioreactors

A bioreactor in which living yeast cells are sandwiched between an ultrafiltration membrane and a reverse osmosis membrane was constructed, and experiments were performed for the conversion of substrate glucose to product ethanol. A set of equations that include both transport through a series of barrier layers and bioreaction rate were developed to predict the performance of the sandwich bioreactor. The above equations were solved by using numerical values for the transport parameter and the bioreaction rate constant, and the results are compared with the experimental data.
Glass transition temperature and critical properties

Abstract In a preceding paper it was shown that for high molecular weight polymers, the volume of the repeating unit at T g is proportional to the total free space defined as V c − V 0 where V c is the volume of the repeating unit at the critical temperature and V 0 is the volume of the repeating unit at absolute zero. Here it will be demonstrated that this proportionality is also true for a host of low molecular weight liquids. In addition, an empirical method of estimating T c for a high molecular weight polymer is proposed which provides values of T c which are consistent with those for low molecular weight liquids.
Nucleus-nucleus scattering at high energies

Nucleus-nucleus scattering is treated in the Glauber approximation. The usual optical limit result, generally thought to improve as the number of nucleons in the colliding nuclei increases, is found to be the first term of a series which diverges for large nuclei. Corrections to the optical limit are obtained which provide a means of performing realistic calculations for collisions involving light nuclei. Total cross section predictions agree well with recent measurements.
The diffusion of core publications in American sociology: A replication

This research explores the role of articles published in three core general sociological journals during 1960 and 1973. It is suggested that citations from subsequently published articles indicate the extent to which publications play an integrating role in the discipline. Citations from the three core journals and seven specialty journals for a period of ten years were recorded. The research raises questions concerning the extent to which core journal articles are relevant to publications in specialty journals and the extent to which professional rewards should be attached to publishing in the American Sociological Review, American Journal of Sociology and Social Forces.
Effects of Lubricant Viscosity on Ring/Liner Friction in Advanced Reciprocating Engine Systems

The piston ring-pack contributes a large portion of the mechanical losses in an internal combustion engine. In this study, the effects of lubricant viscosity are evaluated with the goal of reducing these mechanical losses. Oil viscosity affects friction directly in the hydrodynamic regime, where hydrodynamic friction increases with viscosity. It also influences boundary friction indirectly via oil film thickness — higher viscosity causes oil films to be thicker, which reduces asperity contact. At the optimum viscosity (the viscosity at which minimum friction losses are incurred) there is a balance between these hydrodynamic and boundary effects. As piston speed, ring loading, and other parameters change during the engine cycle, the optimum oil viscosity also changes. If the variation of viscosity could be controlled during the cycle, it could be maintained at an optimum at all times. In this study, several theoretical and realistic cases were studied to quantify the friction benefit that could be obtained if this were possible. Idealized cases with low viscosity near mid-stroke (to reduce hydrodynamic friction) and high viscosity near end-strokes (to reduce boundary contact) were considered, as were several more realistic cases based on temperature and shear-rate dependencies. It was found that, for the oil control ring studied, the effect on friction of keeping viscosity high near end-strokes is very small, and does not provide a substantial benefit (in terms of friction) over allowing viscosity to vary naturally with temperature and shear rate. Two mechanisms lead to the relatively small size of the friction benefit: the contribution to total cycle ring friction from the dead-center area is small, because of low piston speeds there; and any reduction in asperity contact due to increased viscosity is accompanied by an increase in hydrodynamic friction, which cancels out some of the benefit. Oil viscosity near mid-stroke, where most of the ring/liner friction is generated, is the dominant viscosity that controls the overall friction losses for the ring. Although its contribution to friction reduction is not large, maintaining high lubricant viscosity near dead-centers can lead to a reduction in wear in that region, because asperity contact decreases. For the ring-pack studied, a friction reduction of ∼7% is predicted when viscosity is reduced in the mid-stroke region (based on OCR effects alone). If end-stroke viscosity is also kept high, the end-stroke regions, where current engines experience the most wear, will see a reduction in asperity contact (although there will still be a slight wear increase in the mid-stroke). An end-stroke wear reduction of up to 25% is predicted by the current model.© 2006 ASME
On-line sulfur isotope analysis of organic material by direct combustion: preliminary results and potential applications.

Abstract Sulfur isotopes have received little attention in ecology studies because plant and animal materials typically have low sulfur concentrations (< 1 wt.%) necessitating labor-intensive chemical extraction prior to analysis. To address the potential of direct combustion of organic material in an elemental analyzer coupled with a mass spectrometer, we compared results obtained by direct combustion to results obtained by sulfur extraction with Eschka's mixture. Direct combustion of peat and animal tissue gave reproducibility of better than 0.5‰ and on average, values are 0.8‰ higher than values obtained by Eschka extraction. Successful direct combustion of organic material appears to be a function of sample matrix and sulfur concentration. Initial results indicate that direct combustion provides fast, reliable results with minimal preparation. Pilot studies underway include defining bear diets and examining fluctuations between freshwater and brackish water in coastal environments.
Queueing system with finite memory and jump intensity of the arrival process

We consider a single-server queueing system (QS) with finite memory and exponential service with parameter µ. The QS is fed by a doubly stochastic Poisson flow whose intensity ?(t) is a jump process. We propose a matrix and a functional-analytical method to study stationary and nonstationary characteristics of the QS; we also prove existence and uniqueness of a stationary regime and stabilization of a nonstationary regime of the QS. Results of numerical analysis are discussed.
Divergent pathways of programming: prenatal vs. postnatal protein undernutrition.

as first proposed by David Barker ([2][1]) and now supported by numerous epidemiological and experimental studies ([1][2], [12][3], [21][4]), fetal undernutrition leads to permanent structural and physiological alterations resulting in the development of hypertension and cardiovascular disease.
Two aspects of quantum monte carlo: Determination of accurate wavefunctions and determination of potential energy surfaces of molecules

Two aspects of quantum Monte Carlo are discussed. First, we review a procedure for obtaining trial wavefunctions for use in quantum Monte Carlo simulations that have both smaller statistical errors and improved expectation values than commonly used functions. Second, we present a correlated sampling approach for calculating energy differences in variational Monte Carlo much more accurately than the values of the energies. This method is used to calculate the potential energy surfaces of H2 and BH. In the case of BH, at bond lengths 10% different from the reference geometry, the reduced statistical error in the relative energy results in a factor of 3000 saving in computer time.
Interactions of Core−Shell Silica Nanoparticles in Liquid Carbon Dioxide Measured by Dynamic Light Scattering

The effects of solvent density on interparticle interactions between dispersed core−shell silica nanoparticles in liquid CO2 were investigated in terms of diffusional second virial coefficients measured by dynamic light scattering. A porous cross-linked polymeric shell was formed about a hydrophilic silica core with a trifunctional silylating agent, (heptadecafluoro-1,1,2,2-tetrahydrodecyl)triethoxy silane. The addition of the porous polymeric shell weakened the Hamaker interactions between particles enabling dispersibility at low CO2 pressures, even as low as the vapor pressure, with only a stir bar. With dynamic light scattering, the particle size and degree of aggregation were measured in ethanol, the solvent used for synthesis of the shells, and in CO2 as a function of both the silane:silica (wt:wt) ratio and the silane addition rate. Particles in ethanol with thick shells could be dried and redispersed in CO2, whereas particles with thin shells were dispersible in CO2 only when added to CO2 while sti...
Living up to our Humanity: The Elevated Extinction Rate Event and What it Says About Us

Either we are in an elevated extinction rate event or in a mass extinction. Scientists disagree, and the matter cannot be resolved empirically until it is too late. We are the cause of the elevated extinction rate. What does this say about us, we who are Homo sapiens—the wise hominid? Beginning with the Renaissance and spreading during the 18th century, the normative notion of humanity has arisen to stand for what expresses our dignity as humans—specifically our thoughtfulness, in the double sense of our capacity for reasoned choice and our capacity to enter sympathetically into the lives of others considering their good outside of the egotistical orbit of our own. Concurrent with this tradition has been a counter-current of critical thought viewing humans as self-defeating or self-destructive beings. This view reached great heights in the 20th century. Our causing an elevated extinction rate is largely unintentional and goes against our humanity in form as well as in content. Accordingly, it shows us to ...
Design and FE analysis of surface mounted permanent magnet motor/generator for high-speed modular flywheel energy storage systems

Storage is an extremely important area of research and has the potential of furthering the integration of renewables in the grid. The concept proposed here is to design a ceramic-based surface-mounted permanent-magnet (PM) motor/generator for the modular flywheel storage units those are distributed to allow local generation to be used for consumption locally, thus avoiding losses on the transmission and distribution grid as much as possible. Use of ceramic magnets is advantageous because of their higher operating temperatures, easy availability at lower cost, and lower iron losses owing to lower operating flux densities. A 2.5 kW, 24,000 rpm, surface-mounted PM Motor suitable for a 10-kWh storage system is designed and then analyzed using the Finite Element Method. The designed motor with the airgap flux density of 0.3 T results in over 98 percent efficiency, negligible rotor losses, and very low torque ripple of 6.25%.
Electron propagator theory of BS2 and BS−2 electronic structure

Abstract Electron propagator calculations on the vertical and adiabatic ionization energies of BS − 2 yield structural information on ground and excited states of BS 2 . Analytical gradient techniques for BS 2 geometry optimizations and renormalized self-energies for the evaluation of vertical ionization energies are employed. The calculated adiabatic electron affinity of BS 2 is 3.63 eV. Geometry optimizations and force constant calculations arrive at D ∞h structures for all states. Harmonic vibrational frequencies are in reasonable agreement with experimental spectra. Adiabatic excitation energies of BS 2 are inferred from the anion's adiabatic ionization energies. Potential and electric field expectation values of the Feynman-Dyson amplitudes provide a one-electron picture of how removal of an electron leads to bond length changes.
Do peer-reviewed journal papers result from meeting abstracts of the Biennial Conference on the Biology of Marine Mammals?

Peer-reviewed publication is at the core of scientific communication. However, with the exception of biomedicine, there has been little analysis of the rate of peer-reviewed publication resulting from conference abstracts. This study examined a random sample of abstracts from the 1989 and 1991 Biennial Conferences on the Biology of Marine Mammals to determine how many were published as peer-reviewed papers. Publication rates were 51.4% (±4.7%) and 51.2% (±4.6%), respectively. This low abstract-to-publication rate, coupled with editorial policies prohibiting citation of conference abstracts in some journals, limits access to recent research, and thus affects the vibrance of the discipline.
Firm‐Size Wage Gaps, Job Responsibility, and Hierarchical Matching

I present the fact that wage gaps due to firm size increase with job responsibility. I use Swedish data to determine whether wage gaps increase with a direct measure of job responsibility, to compare the age patterns of the wage gaps for blue‐ and white‐collar workers, and to compare wages by job responsibility and spans of control. With U.S. data, I compare supervisory to nonsupervisory occupations and find that wage gaps increase with job responsibility for most occupational ladders. This fact is consistent with hierarchical matching models in which the larger number of subordinates amplifies managerial talent.
Sequential blanking: A U-shaped function

The present study, employing a computer-based cathode-ray tube display system, involved four separate experiments directed to determining if sequential blanking consistently yields a U-shaped function with a variety of input configurations. U-shaped functions were found in all four experiments, and it was concluded that such functions are typical of sequential-blanking phenomena.
Disulfiram treatment increases plasma and red blood cell acetaldehyde in abstinent alcoholics.

BACKGROUND Much of alcohol's toxicity is due to its product, acetaldehyde. The role of acetaldehyde derived from endogenous sources was assessed in alcoholic patients administered disulfiram, an inhibitor of aldehyde dehydrogenase. METHODS The first part of the study included 23 subjects without biochemical or clinical evidence of chronic liver disease who were abstinent for 2 weeks; 11 patients were started on disulfiram (250 mg/day), whereas the other 12 were not given disulfiram and served as controls. The second part of the study included 13 alcoholic patients with clinical or pathological evidence of cirrhosis who also were administered disulfiram for 2 weeks. Plasma and red blood cell (RBC) acetaldehyde as well as serum transaminases were measured at baseline and after 1 and 2 weeks of treatment. RESULTS In the disulfiram-treated group of alcoholics without known cirrhosis, RBC acetaldehyde levels increased from the pretreatment value of 2.98+/-0.18 microM to 4.14+/-0.33 microM after 1 week and to 4.14+/-0.26 microM after 2 weeks of treatment (p < 0.001). Compared with the pretreatment values (2.07+/-0.24 microM), plasma acetaldehyde levels also increased after 1 week (3.18+/-0.32 microM) and 2 weeks (3.15+/-0.26 microM) of disulfiram treatment (p < 0.001). There were no significant differences in sequential levels measured in either plasma or RBC acetaldehyde levels in patients who were not administered disulfiram. In the group of cirrhotic patients, the mean baseline RBC acetaldehyde value (3.60+/-0.22 microM) was significantly higher than in noncirrhotics. Disulfiram therapy increased the RBC acetaldehyde after 1 week (4.63+/-0.27 microM, p < 0.001) and 2 weeks of treatment (4.06+/-0.28 microM, p < 0.05). Compared with baseline values, plasma acetaldehyde levels were significantly higher after 1 week but not after 2 weeks of disulfiram. There were no significant differences among serum transaminases in alcoholics administered disulfiram, although three cirrhotic patients did have clinically significant elevations. CONCLUSIONS In abstaining subjects given disulfiram, acetaldehyde concentrations increase, possibly due to diminished catabolism of endogenously generated acetaldehyde. Disulfiram should be given cautiously, especially in patients with cirrhosis.
Differences between Elementary and Middle School Teachers and Students: A Goal Theory Approach

The early adolescent years are characterized by a negative shift in motivational orientation for a number of children. It has been suggested that this change is related to differences between the learning environments in elementary and middle level schools. In particular, some goal theorists have suggested that middle level schools stress performance goals more and task goals less than do elementary schools. In this study, comparisons based on survey data indicated that middle school teachers and students perceive the school culture as more performance-focused and less task-focused than do elementary teachers and students. In addition, elementary school teachers use instructional practices that emphasize task goals, and endorse task-focused achievement goals for their students, more than do middle school teachers. A perceived stress, in the school, on task goals predicted self-efficacy both for teachers and students, whereas a perceived stress on performance goals was unrelated to self-efficacy.