cssi/SciSciGPT-SciSciNet huggingface dataset:
Development of Low-Level Jets during TAMEX

Abstract Detailed synoptic-scale map analysis and diagnosis for all six low-level jet (LLJ) cases that occurred during the Taiwan Area Mesoscale Experiment (TAMEX) were made to study the structure and the development of the LLJs. It was shown that the development of these LLJs was closely linked to the development of a lee trough to the cast of the Tibetan Plateau. Seasonal change had a profound influence on the secondary circulation across the jet-front system. Before the seasonal transition, the formation of a lee trough with closed isobars in low levels east of the Tibetan Plateau occurred as an upstream short-wave trough moved eastward with strengthening westerlies over the Tibetan Plateau in upper levels. After the development of the lee trough, the southwest flow appeared in the southeast quadrant of the Ice trough. As the upstream trough moved farther eastward, it merged with the lee trough, and the low-level southwesterly flow intensified. For most cases, a midlatitude deep trough was present to t...
Programmer productivity: program efficiency and improvement

As a solution to the problem of program maintenance, it is proposed to maintain a program in several versions. Relevant areas of current research are discussed.
Speed reduction impact of dynamic speed feedback signs on high crash curves

Lane departure crashes are a significant safety concern. The majority of lane departure crashes occur in rural areas, mostly on 2-lane roadways. A disproportionate number of these crashes occur on horizontal curves. Curve related crashes involve a number of roadway and driver causative factors. A primary driver factor is speeding and a large number of run-off-road fatal crashes on curves are speed related. The amount of speed change needed from the tangent speed to the speed required to traverse a curve has an impact on the frequency and severity of crashes on curves.
Lipolytic activity of structurally related agonists in rat epididymal fat tissue in vitro.

Abstract Utilizing the rat epididymal fat pad, the rates of free-fatty acid (FFA) release were quantitated in the presence of various concentrations of agonists. The calculation of intrinsic activity and affinity constants from standard dose-response relationships and double reciprocal plots were employed to establish the structure-activity relationships. Marked changes in the affinity, and to a lesser degree, in the intrinsic activity constants of phenethylamines for the adrenergic-adipose tissue receptor system were produced by alterations of the (a) side chain nitrogen, (b) α- and β-carbon substituents and (c) meta - and para -ring positions of the phenyl nucleus. While optimal activity was possessed by all catecholamines, results with certain noncatecholamines indicated that the catechol moiety was not obligatory for FFA mobilization. The presence of a phenolic group in either ring position was sufficient to produce a maximal response when the β-carbon atom was also hydroxylated. In addition to β-hydroxylation, N -substitution of a bulky alkyl or aralkyl group greatly enhanced the lipolytic activity of the phenethylamine molecule. Optimal activity was obtained with either primary or secondary amines, whereas tertiary amines were characterized as having a decreased affinity. Furthermore, the presence of a β-keto or α-ethyl substituent on the ethylamino-side chain decreased the ability of the agonist to release FFA from adipose tissue in vitro .
Effect of 2‐(4‐Phenylpiperidino)cyclohexanol (AH 5183) on the Veratridine‐Induced Increase in Acetylcholine Synthesis by Rat Hippocampal Tissue

: The intent of this study was to determine whether the drug 2-(4-phenylpiperidino)cyclohexanol (AH 5183 or vesamicol) might inhibit the veratridine-induced increase in acetylcholine (ACh) synthesis by reducing the veratridine-induced activation of a detergent-soluble choline-O-acetyltransferase (EC 2.3.1.6; ChAT) fraction associated with a vesicle-bound store of ACh. When minces of rat hippocampal tissue were loaded with [14C]choline and subsequently depolarized with veratridine, an increase in the synthesis of [14C]ACh occurred that could be abolished by l-AH 5183 (75 nM). When minces were depolarized with veratridine in the presence of l-AH 5183 (75 nM), the depolarization-induced activation of a detergent-soluble ChAT fraction associated with a vesicle-bound store of ACh was blocked. Conversely, the veratridine-induced activation of a water-soluble ChAT fraction believed to be cytosolic was not. AH 5183 also blocked the repletion of the vesicle-bound store with newly synthesized ACh following veratridine-induced depletion of ACh, a result that appeared to be mediated by an effect on the synthesis of ACh at the vesicular surface. These results suggest that veratridine depolarization of rat hippocampal nerve terminals stimulates the synthesis of ACh by activating a detergentsoluble fraction of ChAT closely associated with synaptic vesicle release sites. ACh synthesis and transport at the vesicular surface may be influenced by a common AH 5183-sensitive regulatory protein.
Comparison of response formats for the depression adjective check lists

Studied potential checking and response bias on the Depression Adjective Check Lists (DACL) by comparing the scores of 144 college students on three administration formats: True-false, forced-choice, and standard format. The DACL scores on the three formats were interrelated significantly with one another as well as with an independent measure of state depression of college students (CID). Correlations between the number of depressive adjectives checked and the depression score were significant in the true-false format, but not in the standard format. This argues against the use of the true-false format of the DACL. However, in demonstrating only a weak social desirability response bias, and in failing to reveal the existence of a checking bias, the results give further credence to the use of the standard format.
Continuous versus intermittent feedings of different levels of trimetaphosphate in relation to caries development in the rat.

Abstract Osborne-Mendel rats were fed either of two caries test diets to which trimetaphosphate (TMP) was added continuously, or intermittently (alternating every 24 hr) with an average concentration of either 0.5 or 1.0 per cent. The level of caries was significantly lower for all groups with TMP than in the controls. The groups with different levels of TMP in Diet 585, were not significantly different from each other regardless of concentration or frequency of intake. Caries development on Diet 2000 was inversely related to the average concentration of TMP, but was not different whether consumed continuously or intermittently. As a basis of comparison, it was shown that intermittent feedings of a diet containing corn starch to replace sucrose was associated with as much reduction in caries development on Diet 2000 as the average intake of 1.0 per cent TMP.
Ultrastructure of the spermatheca of the granary weevil, Sitophilus granarius (L.) (Coleoptera : Curculionidae)

Abstract In Sitophilus granarius (L.) the spermatheca is sickle-shaped and is attached to the bursa copulatrix by two nerves and a single spermathecal duct. No muscles are present either on the surface of the spermatheca or the surface of the duct but are found connecting the 2 arms of the spermatheca. The duct is composed of a single layer of epithelial cells, which produce the cuticular lining of the lumen and which appear to perform some osmoregulatory function on the duct contents. Two cell types comprise the spermathecal tissue. The first and most common are epithelial cells, which are derivatives of the integumentary ectoderm, and which are always in association with cuticle. The second type are secretory cells found only in the spermathecal gland. This presumably nutritive gland is attached to the proximal end of the spermatheca adjacent to the attachment of the spermathecal duct. Each glandular cell contains the typical cellular organelles of an active, protein-synthesizing, exocrine cell. The synthesized material is discharged into the central lumen of each cell which connects to epithelial ductules leading out of the gland and into the spermatheca.
Role of H2O2 in the oxidative effects of zinc exposure in human airway epithelial cells.

Human exposure to particulate matter (PM) is a global environmental health concern. Zinc (Zn2+) is a ubiquitous respiratory toxicant that has been associated with PM health effects. However, the molecular mechanism of Zn2+ toxicity is not fully understood. H2O2 and Zn2+ have been shown to mediate signaling leading to adverse cellular responses in the lung and we have previously demonstrated Zn2+ to cause cellular H2O2 production. To determine the role of Zn2+-induced H2O2 production in the human airway epithelial cell response to Zn2+ exposure. BEAS-2B cells expressing the redox-sensitive fluorogenic sensors HyPer (H2O2) or roGFP2 (EGSH) in the cytosol or mitochondria were exposed to 50 µM Zn2+ for 5 min in the presence of 1 µM of the zinc ionophore pyrithione. Intracellular H2O2 levels were modulated using catalase expression either targeted to the cytosol or ectopically to the mitochondria. HO-1 mRNA expression was measured as a downstream marker of response to oxidative stress induced by Zn2+ exposure. Both cytosolic catalase overexpression and ectopic catalase expression in mitochondria were effective in ablating Zn2+-induced elevations in H2O2. Compartment-directed catalase expression blunted Zn2+-induced elevations in cytosolic EGSH and the increased expression of HO-1 mRNA levels. Zn2+ leads to multiple oxidative effects that are exerted through H2O2-dependent and independent mechanisms.
ATOMIC FORCE MICROSCOPE INVESTIGATION OF THE THERMAL STABILITY OF THIN TISI2 FILMS

The thermal stability of TiSi2 films on Si has been studied using the atomic force microscope (AFM). Changes in the surface roughness, film morphology, and sheet resistance were monitored during a series of rapid thermal annealing treatments. A linear increase of the root-mean-square (rms) roughness with time was observed during the early stages of degradation, in agreement with a surface diffusion model of thermal grooving, followed by an apparent saturation roughness that was attributed to the effective rupture of the film.
Earnings surprises and prior insider trading: Tests of joint informativeness

. Building on the notion that both earnings surprises and the level of insider trading are noisy signals of future prospects of the firm, this paper empirically investigates joint informativeness of the two signals surrounding earnings announcements. Classification of a large sample of firms in the time period 1977–81 based both on the levels of earnings surprise and insider trading results in a finer partition informationally, compared to using just one signal. Both additive and interactive effects are observed while analysing the security market response during the three trading days centered on the day of earnings announcements. Over a 19-day postannouncement period, the results are less pronounced. The overall pattern of results implies that each signal may contain information not contained in the other, and/or some of the noise associated with each signal may be interactively resolved at the time of earnings announcements. This inference is robust under many measurement alternatives. Resume. A partir du principe voulant que les benefices imprevus ainsi que l'importance des operations d'inities soient des indicateurs manifestes des perspectives futures de l'entreprise, les auteurs procedent a une etude empirique de la qualite informative conjointe des deux indicateurs dans le cadre des avis de benefices. La classification d'un vaste echantillon d'entreprises pendant la periode 1977–1981 en fonction a la fois du niveau des benefices imprevus et de l'importance des operations d'inities permet un decoupage plus subtil sur le plan informationnel que l'utilisation d'un indicateur unique. Les auteurs observent les effets tant additifs qu'interactifs de cette classification dans l'analyse de la reponse du marche boursier au cours des trois jours de bourse centres sur le jour de la communication des avis de benefices. Pour la periode de 19 jours suivant la periode d'avis, les resultats sont moins accuses. Le modele global des resultats suppose que chaque indicateur peut livrer de l'information que l'autre ne livre pas et qu'une partie de ce que manifeste chaque indicateur peut etre resolue de facon interactive au moment de la communication des avis de benfices. Cette induction resiste a l'epreuve de plusieurs techniques de mesure.
Spectrophotometry of hydroxocobalamin and hemoglobin reveals production of an unanticipated methemoglobin variant

Introduction. Cyanide-poisoned patients often require pulse oximetry and co-oximetry to measure oxyhemoglobin, deoxyhemoglobin, carboxyhemoglobin, and methemoglobin. These and other critical laboratory measurements can be confounded by the cyanide antidote hydroxocobalamin. The postulated mechanism of this confounding is direct optical interference. Methods. The spectra of swine hemoglobin with and without hydroxocobalamin were measured from 450–800 nm. The resulting complex spectrum was divided into hemoglobin, hydroxocobalamin, and a remainder spectrum. Results. The remainder spectrum appears to be a methemoglobin variant quantitatively dependant on the amount of hydroxocobalamin added to the hemoglobin solution and the presence of oxygen. The Pearson's correlation coefficient comparing the known swine methemoglobin spectrum with the remainder spectrum reveals a very high degree of correlation (r2 = 0.986). Conclusion. This is the first study to document methemoglobin formation caused by hydroxocobalami...
On An Endpoint Case Of The Klainerman­Machedon Estimates

(1999). On An Endpoint Case Of The Klainerman­Machedon Estimates. Communications in Partial Differential Equations: Vol. 25, No. 7-8, pp. 1537-1547.
Urban Elementary Teachers’ Perspectives on Teaching Science to English Language Learners

This descriptive study examined urban elementary school teachers’ perceptions of their science content knowledge, science teaching practices, and support for language development of English language learners. Also examined were teachers’ perceptions of organizational supports and barriers associated with teaching science to nonmainstream students. The study involved 221 third- through fifth-grade teachers from 15 urban elementary schools in a large school district. The teachers completed a survey in the spring of 2005. The internal consistency reliability estimates, Cronbach α, for scales created from the survey items were within an acceptable range. The teachers reported that they were generally knowledgeable about science topics at their grade level and that they taught science to promote students’ understanding and inquiry. In contrast, the teachers reported rarely discussing student diversity in their own teaching or with other teachers at their schools. The teachers identified specific organizational supports and barriers in teaching science with diverse student groups at both the school and classroom levels.
Large cell change (liver cell dysplasia) and hepatocellular carcinoma in cirrhosis: Matched case-control study, pathological analysis, and pathogenetic hypothesis

Large cell change (LCC), characterized by cellular enlargement, nuclear pleomorphism and hyperchromasia, and multinucleation of hepatocytes, is a common lesion in cirrhotic livers, but its nature, significance, and pathogenesis remain uncertain. Therefore, we assessed the prognostic value of LCC as a marker of subsequent hepatocellular carcinoma (HCC) through a case-control study that compared pretransplant liver biopsy specimens from 37 cirrhotic liver transplant recipients with HCC to specimens from a control group of recipients without HCC, matched for sex, age (+/-5 years), and cause of cirrhosis. LCC was identified in 16 (43%) of the study and 7 (19%) of the control group biopsy specimens. By matched-pair analysis, LCC conveyed a moderately increased risk of later HCC with an estimated odds ratio of 3.3 (95% CI, 1.2-15; P = .038). However, a pathology review of 45 HCCs showed adjoining LCC in only 12 (27%) and did not suggest a morphological transition or a histogenetic association between the two lesions. LCC hepatocytes displayed a low proliferative rate by Ki-67 or proliferating cell nuclear antigen immunostaining (labeling indices of 0.27 and 0.73) but showed a greater degree of apoptosis than normal hepatocytes (labeling indices of 1.9 and 0.23; P = .03) To reconcile these findings, we propose that LCC derives from derangements in the hepatocyte's normal process of polyploidization. Such derangements, possibly caused by chronic inflammation-induced DNA damage, could yield a population of enlarged liver cells with nuclear atypia and pleomorphism, frequent binuclearity, and minimal proliferation. According to this hypothesis, LCC would be a habitual feature of cirrhosis and a regular accompaniment of HCC but would not represent a direct malignant precursor.
Real-time edge-enhanced dynamic correlation and predictive open-loop car-following control for robust tracking

We present a robust framework for a real-time visual tracking system, based on a BPNN-controlled fast normalized correlation (BCFNC) algorithm and a predictive open-loop car-following control (POL-CFC) strategy. The search for the target is carried out in a dynamically generated resizable search-window. In order to achieve the robustness, we use some edge-enhancement operations before the correlation operation, and introduce an adaptive template-updating scheme. The proposed tracking algorithm is compared with various correlation-based techniques and (in some cases) with the mean-shift and the condensation trackers on real-world scenarios. A significant improvement in efficiency and robustness is reported. The POL-CFC algorithm approximates the current velocity of an open-loop pan-tilt unit, computes the predicted relative-velocity of the object using Kalman filter, and generates the precise control signals to move the camera accurately towards the maneuvering target regardless of its changing velocity. The proposed system works in real-time at the speed of 25–200 frames/ second depending on the template size, and it can persistently track a distant or near object even in the presence of object fading, low-contrast imagery, noise, short-lived background clutter, object-scaling, changing object-velocity, varying illumination, object maneuvering, multiple objects, obscuration, and sudden occlusion.
Characterization of bacterial cell membrane attachment sites of plasmid R6K.

Abstract In vitrobinding studies revealed that plasmid R6K could attach to both inner and outer membrane fractions of its host cell,Escherichia coli.Derivatives of R6K carrying one or two of its three origins of replication could not bind stably to the same membrane fractions in the presence of salt. However, the derivative, pRK35, carrying the intact three origins of replication could bind stably to membrane fractions from its host in the presence or absence of salt. These observations suggest that the three origins of DNA replication must be contiguous for stable binding of the plasmid to the cell membrane. The results of binding experiments showed that plasmid R6K bound competitively with pRK35 as well as the heterologous plasmid, pl524.
Fitness of human immunodeficiency virus type 1 protease inhibitor-selected single mutants.

Human immunodeficiency virus type 1 (HIV-1) evolution under chemotherapeutic selection pressure in vivo involves a complex interplay between an increasing magnitude of drug resistance and changes in viral replicative capacity. To examine the replicative fitness of HIV-1 mutants with single, drug-selected substitutions in protease (PR), we constructed virus that contained the most common mutations in indinavir-selected clinical isolates, PR M46I and V82T, and the most common polymorphic change in drug-naive patients, PR L63P. These mutants were competed in vitro in the absence of drug against the otherwise isogenic WT virus (NL4-3). Phenotypic drug susceptibility was determined with a recombinant virus assay using a single cycle of virus growth. PR M46I and L63P were as fit as WT. However, PR V82T was out-competed by WT. None of these mutants had appreciable phenotypic resistance to any of the protease inhibitors, including indinavir. The PRV82T mutant was hypersusceptible to saquinavir. Thus, the impaired fitness of the V82T single mutant is consistent with its low frequency in protease inhibitor-naive patients. The similar fitness of WT (NL4-3), L63P, and M46I is consistent with the common occurrence of L63P in the absence of protease inhibitor-selection pressure, but not with the rare detection of M46I in drug-naive patients.
Dual-reactive B cells are autoreactive and highly enriched in the plasmablast and memory B cell subsets of autoimmune mice

Rare dual-reactive B cells expressing two types of Ig light or heavy chains have been shown to participate in immune responses and differentiate into IgG(+) cells in healthy mice. These cells are generated more often in autoreactive mice, leading us to hypothesize they might be relevant in autoimmunity. Using mice bearing Igk allotypic markers and a wild-type Ig repertoire, we demonstrate that the generation of dual-κ B cells increases with age and disease progression in autoimmune-prone MRL and MRL/lpr mice. These dual-reactive cells express markers of activation and are more frequently autoreactive than single-reactive B cells. Moreover, dual-κ B cells represent up to half of plasmablasts and memory B cells in autoimmune mice, whereas they remain infrequent in healthy mice. Differentiation of dual-κ B cells into plasmablasts is driven by MRL genes, whereas the maintenance of IgG(+) cells is partly dependent on Fas inactivation. Furthermore, dual-κ B cells that differentiate into plasmablasts retain the capacity to secrete autoantibodies. Overall, our study indicates that dual-reactive B cells significantly contribute to the plasmablast and memory B cell populations of autoimmune-prone mice suggesting a role in autoimmunity.
Fabrication of Low Cost Metal-Based Micro-Capillary Channels for Thermal Scavenging and Heat Transfer

In this work, we present a low cost method for the fabrication of a heat exchanger utilizing metal-based microchannels using the LiGA technique. Lithography is used to pattern dry film negative photoresist (Ordyl P-50100) on the substrate. The resist is laminated over the substrate and exposed with a UV source. The use of dry film resist allows for simple and inexpensive microchannel patterns without requiring advanced cleanroom equipment. Following the lithography process, electrodepostion of metals is used to fill the recesses patterned in the resist. In this work, nickel has been electroplated into the bounding resist structure. After electroplating, the remaining resist is dissolved leaving free standing metal structures. The fabricated exchanger is then evaluated based on thermal absorption of simulated waste heat sources and capillary action of the metal channels themselves.Channels are fabricated to heights of 60, 70 and 90 μm respectively using these methods. Working fluid mass transfer rate from the heated MHE is utilized as a basic metric of operation. The mass transfer rate recorded from the nickel-based MHE is 3.35, 3.37 and 3.41 mg/s respectively for the different channel heights. This implies an effective thermal power consumption rate of 2.54, 2.56 and 2.59 kW/m2 respectively.Copyright © 2013 by ASME
Water and magmas: application of the Gibbs-Duhem equation: a response

A rebuttal is presented to the assertions of Dye and Vogel that the conclusion by Burnham (1975a, b) regarding Raoultian (''ideal'') mixing behavior of the aluminosilicate components in a wide range of melt compositions is valid. It is emphasized that the mixing behavior of one component in a three-component system imposes constraints on the mixing behavior of the other two components, even when the form of the Gibbs--Duhem equation reduces to that for a two-component system. Indeed, the key element in Burnham's conclusion of ideal behavior for the aluminosilicate components in igneous-rock melts is the powerful constraint imposed by the fact that the activity of H/sub 2/O (a/sub H/sub 2/O/), hence its partial molal Gibbs free energy (anti G/sub H/sub 2/O/), is a function only of its mole fraction (X/sub H/sub 2/O/) at a given temperature and pressure (Burnham, 1975b, eqs. 3 and 4). Thus, the objective here is to show, with reference to the generalized ternary system 1-2-3, how imposition of this constraint for component 3 leads to the conclusion that components 1 and 2 mix ideally. (JGB)
Methods for determination of labile soil organic matter: An overview

Soil organic matter (SOM) can be divided into three main pools: labile, stable and inert. Research over recent years has focused on the labile fraction (LF), as it is considered a quickly reactive indicator of soil productivity and health, and important as a supply of energy for soil micro-organisms. A wide spectrum of analytical methods has been used to determine and/or evaluate LF, based on physical, chemical and biochemical principles. The advantages and disadvantages of each technique are explored in this work, but none of the methods can determine LF sufficiently, either because a part of the LF is not involved or because further characterisation is missing. Although analytical methods are widely used to evaluate changes in soil management or organic carbon turnover, the practical question of the quantity and quality of SOM cannot be answered completely. It is also suggested that future research should focus on the interactions among SOM fractions and their better chemical and functional characterisation. It is possible to use a combination of the analytical methods reviewed here in order to accomplish this objective.
Determining who to question, what to ask, and how much information to ask for: the development of inquiry in young children.

Abstract To obtain reliable information, it is important to identify and effectively question knowledgeable informants. Two experiments examined how age and the ease of distinguishing between reliable and unreliable sources influence children’s ability to effectively question those sources to solve problems. A sample of 3- to 5-year-olds was introduced to a knowledgeable informant contrasted with an informant who always gave inaccurate answers or one who always indicated ignorance. Children were generally better at determining which informant to question when a knowledgeable informant was contrasted with an ignorant informant than when a knowledgeable informant was contrasted with an inaccurate informant. In some cases, age also influenced the ability to determine who to question and what to ask. Importantly, in both experiments, the strongest predictor of accuracy was whether children had acquired sufficient information; successful problem solving required integrating knowledge of who to question, what to ask, and how much information to ask for.
Altered structural and functional synaptic plasticity with motor skill learning in a mouse model of fragile X syndrome

Fragile X syndrome (FXS) is the most common inherited intellectual disability. FXS results from a mutation that causes silencing of the FMR1 gene, which encodes the fragile X mental retardation protein. Patients with FXS exhibit a range of neurological deficits, including motor skill deficits. Here, we have investigated motor skill learning and its synaptic correlates in the fmr1 knock-out (KO) mouse. We find that fmr1 KO mice have impaired motor skill learning of a forelimb-reaching task, compared with their wild-type (WT) littermate controls. Electrophysiological recordings from the forelimb region of the primary motor cortex demonstrated reduced, training-induced synaptic strengthening in the trained hemisphere. Moreover, long-term potentiation (LTP) is impaired in the fmr1 KO mouse, and motor skill training does not occlude LTP as it does in the WT mice. Whereas motor skill training induces an increase of synaptic AMPA-type glutamate receptor subunit 1 (GluA1), there is a delay in GluA1 increase in the trained hemisphere of the fmr1 KO mice. Using transcranial in vivo multiphoton microscopy, we find that fmr1 KO mice have similar spine density but increased dendritic spine turnover compared with WT mice. Finally, we report that motor skill training-induced formation of dendritic spines is impaired in fmr1 KO mice. We conclude that FMRP plays a role in motor skill learning and that reduced functional and structural synaptic plasticity might underlie the behavioral deficit in the fmr1 KO mouse.
Epidemiological Evaluation of Blood Culture Patterns among Neonates Receiving Vancomycin

The objective of this study was to assess the frequency of blood culture (BC) collection among neonates who received vancomycin. Demographic, clinical, microbiologic, and pharmacy data were collected for 1275 neonates (postnatal age 0–27 days) who received vancomycin at an Intermountain Healthcare facility between 1/2006 and 9/2011. Neonates treated with vancomycin had a BC collected 94 % (n = 1198) of the time, of which 37 % (n = 448) grew one or more bacterial organisms (BC positive). Of these, 1 % (n = 5) grew methicillin-resistant Staphylococcus aureus (MRSA), 71 % (n = 320) grew coagulase-negative Staphylococci (CoNS), 9 % (n = 40) grew methicillin-sensitive Staphylococcus aureus (MSSA), and 22 % (n = 97) grew other bacterial species (total exceeds 100 % due to co-detection). In patients with negative BC or no BC, vancomycin therapy was extended beyond 72 h 52 % of the time. The median duration of vancomycin therapy for patients with a negative BC was 4 (IQR: 2–10) days. BCs were frequently obtained among neonates who received vancomycin. Vancomycin therapy beyond the conventional ‘empiric’ treatment window of 48–72 h was common without isolation of resistant gram-positive bacteria.
Desmosomes and their components after cell dissociation and reaggregation in the presence of cytochalasin B.

Corneal epithelial cells of the chick, in a stage in which desmosomes are forming, have been dispersed and reassociated in the presence of cytochalasin B in order to assess the affects of the drug on desmosomes. Any affect on these adhesive structures or on normal cell apposition as determined by fine structure would provide morphological evidence for interference with cell adhesion. Dispersed cells in concentrations of cytochalasin B of 3 μg/ml or more showed stabilization of the cell membrane in that after desmosome disruption single plaques remained at the cell surface rather than entering the cytoplasm on vacuoles, as occurs in normal medium. Interference with cell surface apposition particularly at early stages of aggregation provided additional evidence for surface immobility. Despite these effects the presence of a stainable surface coat could be demonstrated early in reaggregation and by 24 hours of culture cell surfaces became closely apposed over wide areas and desmosomes formed between cells and in some cases between different parts of the same cell even in dosages of 10 μg/ml. Thus interference with cell adhesion in corneal cells as measured by these criteria appears to be related to immobility rather than to adhesive properties. These findings bear on studies of cell sorting in the presence of cytochalasin B.
A mathematical model in immunoregulation where the spleen has a pivotal role

Abstract A simple mathematical model is introduced to investigate collaborative interactions between thymus-derived T and bursal-influenced B lymphocytes in the presence of specific antigen, intravenously presented. Such encounters are assumed to lead to humoral antibody response, and antigen interacting to produce effector T cells in the absence of B cells is assumed to produce cell mediated immunity. The model is used further to consider (i) the resultant distribution of effector T cells, (ii) the effect of splenectomy on collaborative T-B cell interactions, and (iii) recent data relating to portal cirrhosis, sickle cell anemia, malignant lymphomas, and diseases involving an impaired thymic function. It is concluded that for soluble antigen, such T-B cell encounters normally predominate in the spleen, as compared with the lymph nodes. Developing principles of immunoregulation may be applied to the theoretical basis of the model.
Absence of spontaneous persistent current for interacting fermions in a one-dimensional mesoscopic ring.

We address the issue of whether a system of interacting electrons confined to a one-dimensional ring can sustain a spontaneous persistent current in the absence of an externally applied flux. The current-current coupling between electrons, describing radiative back-action effects, is exactly treated in the formalism of quantum electrodynamics, where the electrons interact via the exchange of virtual photons. In addition, the instantaneous screened Coulomb potential is taken into account using the Luttinger liquid model including finite-size parity effects. The partition function is calculated exactly, with the result that the system does not possess a spontaneous persistent current. We show that, in the presence of an external flux, the amplitude of the (conventional) persistent current is reduced by quantum fluctuations of the internal transverse electromagnetic field. These corrections can be expressed in terms of the self-induction of the ring and are shown to be of first and higher order in the small dimensionless parameter \ensuremath{\alpha}${\mathit{v}}_{\mathit{F}}^{\mathrm{*}}$/c, where \ensuremath{\alpha} is the fine-structure constant and ${\mathit{v}}_{\mathit{F}}^{\mathrm{*}}$ the Fermi velocity renormalized through Coulomb interactions.
Biochemical changes in the central nervous system with age in the rat

Studies dealing with biochemistry of the central nervous system of rats have been reviewed. Data on the effects of age on enzyme activity and cellular substrates have been summarized in tabular form. In general, it can be concluded that biochemical functions dealing with anabolism decrease whereas those dealing with catabolism increase as aging progresses.
Correlation of growth and aspartate transcarbamylase activity in higher plants

Abstract Carbamyl phosphate-aspartate transcarbamylase (aspartate transcarbamylase) has been determined in various portions of the following plants: corn, bean, pea, soybean, sunflower, and tobacco. The enzyme was found to be present predominantly in the supernatant fraction of homogenates prepared with 0.1 M KHCO 3 solution. The enzyme from soybean seedling roots has a pH optimum of 9.6. Aspartate transcarbamylase activity was found to be highest in growing portions of roots, leaves, and shoots. The seedling roots of soybean, corn, sunflower, and pea had specific activities of aspartate transcarbamylase as follows: 0.82, 0.66, 0.51, and 0.19, respectively. Young, growing tobacco leaves had 10 times the specific activity of aspartate transcarbamylase as compared with mature leaves. The specific activities of aspartate transcarbamylase in root and shoot of soybean seedlings were approximately the same, but about 5 times greater than that of the cotyledon.
A simple assay of cyclic-AMP phosphodiesterase in the presence of interfering enzymes in Vibrio harveyi

Abstract PEI-cellulose thin layer chromatography is used to separate the reaction products formed from cyclic-AMP initiated by phosphodiesterase in crude extracts of bacteria.
Ray trace optimization of a light trapping filtered concentrator for spectrum splitting photovoltaics

A ray trace model of the light trapping filtered concentrator spectrum splitting architecture is presented. The scripted ray trace allows for examination of non-idealities in materials and design that were not addressed in previous analytical investigations of this optical design. The design of the angle restricting elements is examined with regards to optical efficiency and system efficiency. In addition, the scripted ray trace enables rapid evaluation of multiple candidate filter sets and optimization of the optical design for each set via a gradient ascent algorithm. A discussion of filter design considerations and insight provided by the ray trace model evaluations is presented.
Developmental origins of precocial forelimbs in marsupial neonates

Marsupial mammals are born in an embryonic state, as compared with their eutherian counterparts, yet certain features are accelerated. The most conspicuous of these features are the precocial forelimbs, which the newborns use to climb unaided from the opening of the birth canal to the teat. The developmental mechanisms that produce this acceleration are unknown. Here we show that heterochronic and heterotopic changes early in limb development contribute to forelimb acceleration. Using Tbx5 and Tbx4 as fore- and hindlimb field markers, respectively, we have found that, compared with mouse, both limb fields arise notably early during opossum development. Patterning of the forelimb buds is also accelerated, as Shh expression appears early relative to the outgrowth of the bud itself. In addition, the forelimb fields and forelimb myocyte allocation are increased in size and number, respectively, and migration of the spinal nerves into the forelimb bud has been modified. This shift in the extent of the forelimb field is accompanied by shifts in Hox gene expression along the anterior-posterior axis. Furthermore, we found that both fore- and hindlimb fields arise gradually during gastrulation and extension of the embryonic axis, in contrast to the appearance of the limb fields in their entirety in all other known cases. Our results show a surprising evolutionary flexibility in the early limb development program of amniotes and rule out the induction of the limb fields by mature structures such as the somites or mesonephros.
Two-particle elastic scattering in a finite volume including QED

The presence of long-range interactions violates a condition necessary to relate the energy of two particles in a finite volume to their S-matrix elements in the manner of L\"uscher. While in infinite volume, QED contributions to low-energy charged-particle scattering must be resummed to all orders in perturbation theory (the Coulomb ladder diagrams), in a finite volume the momentum operator is gapped, allowing for a perturbative treatment. The leading QED corrections to the two-particle finite-volume energy quantization condition below the inelastic threshold, as well as approximate formulas for energy eigenvalues, are obtained. In particular, we focus on two spinless hadrons in the ${A}_{1}^{+}$ irreducible representation of the cubic group, and truncate the strong interactions to the s-wave. These results are necessary for the analysis of lattice $\mathrm{QCD}+\mathrm{QED}$ calculations of charged-hadron interactions, and can be straightforwardly generalized to other representations of the cubic group, to hadrons with spin, and to include higher partial waves.
Incidence of varicoceles in men with primary and secondary infertility

Abstract Objectives To determine whether varicoceles are more prevalent in men with secondary infertility than in men with primary infertility. Methods The records of 2188 consecutive men attending three infertility centers were reviewed to determine the incidence of varicoceles in men with primary and secondary infertility. In addition, other factors affecting both male and female infertility were assessed in these patients. Results The incidence of varicoceles was not significantly different between the 1447 men with primary infertility versus the 741 men with secondary infertility: 44% and 45%, respectively. The incidence of vasal agenesis was significantly greater in men with primary infertility (P Conclusions These findings do not support the conclusion that varicoceles have a progressive adverse effect on fertility over time and suggest that further study is needed to determine whether varicocele repair is indicated in patients with normal semen parameters.
72 An examination of the periphytic algae in the sheyenne river, north dakota, usa, and the factors influence the community structure

The Sheyenne River is a third order stream in central and eastern North Dakota. The algae in this river had not been previously studied. For this study, periphytic algal samples were collected Fall 1997, April–November 1998, and May–October 1999. Two hundred sixteen periphytic algal taxa were identified. These taxa included 137 Bacillariophyceae, 33 Cyanophyta, 40 Chlorophyta, 8 Xanthophyceae, and 3 Euglenophyta. Several species of algae found in the river appear to be previously undescribed taxa. Two of these organisms were described as new species, Nitzschia sheyennensis and Nitzschia dakotensis (Bacillariophyceae). The distribution of the periphytic algae was correlated to changes in the selected environmental variables using canonical correspondence analysis (CCA) and mult-dimensional scaling (MDS). The statistically significant environmental variables were nitrite-nitrate, pH, arsenic, potassium, magnesium, manganese, and total dissolved solids. A reservoir, Lake Ashtabula on the river was formed by a dam in 1954. In the initial statistical analysis, the effects of this reservoir on the periphytic algae downstream were so great that an upstream/downstream covariable had to be used. Further statistical analysis was used to determined that this effect could be correlated to changes in the nutrient levels rather than hydrologic changes.
Surgery for Ischemic Mitral Regurgitation

Defining the appropriate management of mitral regurgitation secondary to ischemic heart disease — as opposed to primary disease such as rheumatic or myxomatous degeneration — has proved elusive. Coronary artery disease is common, and so is associated mitral regurgitation, at least to some degree. The latter has been recognized as an unfavorable prognostic sign for more than 25 years1 and thus has been a target of surgical interest, with the goal of negating the adverse effects on late survival without paying too much of an up-front cost in terms of perioperative mortality.2 When the regurgitation is severe, debate has centered . . .
The isolation and characterization of ribonucleic acid from yeast macromolecular ribonucleoprotein.

Abstract By precipitating RNA quantitatively from the macromolecular ribonucleoprotein of yeast in 1 M MgCl 2 , 1 M CaCl 2 , 1 M BaCl 2 or 2 M LiCl and then redissolving it in 0.001 M MgSO 4 or 0.001 M CaCl 2 , a study was made of the properties of RNA and its conjugate protein in order to determine whether it is the RNA or the protein that is bound together by Mg 2+ or Ca 2+ in the subunits of ribonucleoprotein. The RNA isolated from 1 M MgCl 2 and 1 M CaCl 2 has a sedimentation coefficient of 5.3 S and a molecular weight of 1.15·10 5 ; that from 1 M BaCl 2 and 2 M LiCl has a sedimentation coefficient of 3.3 S with a molecular weight of 1.95·10 4 . The interconversion between the 5.3 S and 3.3-S RNA is reversible. The conjugate protein, which is soluble in these salt solutions, has a sedimentation coefficient of approx. 2 S.
Distribution of omega-3 and omega-6 fatty acids in the ether- and ester-linked phosphoglycerides from tissues of the rainbow trout, Salmo gairdneri.

Abstract 1. 1. Data presented here demonstrate that polyunsaturated fatty acids in the phospholipids of rainbow trout tissues are compartmentalized differently than in mammalian tissues. 2. 2. We have determined the distribution of omega-3 (n-3) and omega-6 (n-6) fatty acids in the alkyl-, alk-1-enyl-, and diacyl- subclasses of phosphatidylcholines (PC), phosphatidyl-ethanolamines (PE), phosphatidylinositols (PI), and phosphatidylserines (PS) from gill, kidney and spleen of rainbow trout. 3. 3. Alkyl-linked PC and alk-1-enyl-linked PE were the most abundant ether-containing phospholipids, amounting to 10–15% of each class; no ether-linked PI or PS was detected. 4. 4. C20:4 n-6 was found in high concentrations only in PI; the n-3 fatty acids were found in highest concentration in the ether-linked phospholipids as compared with the diacyl subclasses and C20:5 n-3 was especially prevalent in 1-O-alk-1′-enyl-2-acyl-sn-glycero-3-phosphoethanolamine and C22:6 n-3 was prevalent in PS.
High energy density and breakdown strength from β and γ phases in poly(vinylidene fluoride-co-bromotrifluoroethylene) copolymers

Poly(vinylidene fluoride) PVDF-based copolymers represent the state of the art dielectric polymers for high energy density capacitors. Past work on these copolymers has been done with limited emphasis on the effects of copolymer composition and with a limited range of defect monomers, focusing primarily on the commercially available poly(vinylidene fluoride-co-chlorotrifluoroethylene), P(VDF-CTFE), and poly(vinylidene fluoride-co-hexafluoropropylene), P(VDF-HFP), and the processing thereof. To expand on this area of research, copolymers of VDF and bromotrifluoroethylene (BTFE) were synthesized examining the composition range where uniaxial stretching was possible. It is found that P(VDF-BTFE) copolymers with small BTFE contents (< 2 mol %) stabilize the γ phase, compared to P(VDF-CTFE)s and P(VDF-HFP)s that are largely α phase in composition. Furthermore, different from P(VDF-CTFE)s and P(VDF-HFP)s, whose energy storage capabilities depend on the reversibility of the α to β phases transformation, high dis...
Increased expression of the N protein of respiratory syncytial virus stimulates minigenome replication but does not alter the balance between the synthesis of mRNA and antigenome

A popular model for RNA synthesis by nonsegmented negative-strand RNA viruses is that transcription and RNA replication are executed by the same polymerase complex and that there is a dynamic balance between the two processes that is mediated by the nucleocapsid N protein. According to this model, transcription occurs until sufficient soluble N protein accumulates to initiate encapsidation of the nascent RNA product, which somehow switches the polymerase into a readthrough replicative mode. This model was examined for respiratory syncytial virus (RSV) using a reconstituted transcription and RNA replication system that involves a minireplicon and viral proteins that are expressed intracellularly from transfected plasmids. Preliminary experiments showed that reconstituted RNA replication was highly productive, such that on average each molecule of plasmid-supplied minigenome that became encapsidated was amplified 10- to 50-fold. N protein was increased on its own or in concert with the phosphoprotein P and in the presence or absence of the M2 ORF1 transcription elongation factor. The maximum level of N and P protein expression achieved from plasmids equalled or exceeded that obtained in RSV-infected cells. Increased levels of N protein stimulated RNA replication. This is consistent with the idea that RNA replication is dependent on the availability of N protein for encapsidation, which is one postulate of the model. The M2 ORF1 protein had no detectable effect on RNA replication under the various conditions of expression of N and P, which confirmed and extended previous results. However, there was no evidence of a significant switch in positive-sense RNA synthesis from transcription (synthesis of mRNAs) to RNA replication (synthesis of antigenome). The synthesis of positive-sense antigenome and mRNA appeared to occur at a fixed ratio, with mRNA being by far the more abundant product.
Use of synthetic cathinones and cannabimimetics among injection drug users in San Diego, California.

Background Use of synthetic cathinones (SC) and cannabimimetics (i.e., “THC homologues” [TH]) is associated with adverse health effects. We investigated the epidemiology of synthetic drug use among a cohort of injection drug users (IDUs) in San Diego, California.