cssi/SciSciGPT-SciSciNet huggingface dataset:
Neutral proteinase activity produced in vitro by cells of the glomerular mesangium

Neutral proteinase activity produced in vitro by cells of the glomerular mesangium. Cells derived from isolated glomerular tufts of rats were studied in primary tissue culture after the removal of epithelial cells by collagenase treatment. The cultured cells, fusiform or stellate in shape, grew readily over a 12-day period. Immunofluorescence staining was positive for myosin and fibronectin, while negative for Factor VIII, suggesting that the outgrowing cells were derived from the glomerular mesangium. In serum-free culture, these cells produced neutral proteinase activity that occurred as a latent trypsin-activable form (apparent molecular weight range, 78,000 to 100,000 daltons) and in an active form (44,000 to 58,000 daltons). Neutral proteinase activity was inhibited by EDTA and by cysteine, and exhibited a pH optimum of 7.2 to 7.8, characteristic of an extracellularly active metalloendopeptidase. The culture supernate which contained the neutral proteinase activity was capable of degrading purified rat glomerular basement membrane. The release of hydroxyproline-containing fragments from the basement membrane indicated that degradation of the type IV collagen component of the basement membrane was occurring. These findings suggest that the neutral proteinase activity generated by mesangium-derived cells may play a role in the physiologic turnover of glomerular structural proteins in vivo. Activite proteinase neutre produite in vitro par les cellules du mesangium glomerulaire. Les cellules derivant de touffes glomerulaires isolees de rats ont ete etudiees en culture tissulaire primaire apres elimination des cellules epitheliales par traitement a la collagenase. Les cellules en culture, de forme fusiforme ou etoilee, poussaient rapidement, en 12 jours. La coloration en immunofluorescence etait positive pour la myosine et la fibronectine, mais negative pour le facteur VIII, suggerant que les cellules cultivees etaient derivees du mesangium glomerulaire. En culture sans serum, ces cellules produisaient une activite proteinase neutre qui survenait sous une forme latente trypsine-activable (poids moleculaire apparent entre 78 000 et 100 000 daltons), et sous une forme active (44 000 a 58 000 daltons). L'activite proteinase neutre etait inhibee par l'EDTA et par la cysteine, et avait un pH optimum de 7,2 a 7,8, caracteristique d'une metalloendopeptidase active a l'exterieur de la cellule. Le surnageant des cultures contenant l'activite proteinase neutre etait capable de degrader de la membrane basale glomerulaire de rat purifiee. Le relargage de fragments contenant de l'hydroxyproline a partir de la membrane basale indiquait qu'une degradation du constituant collagene de type IV de la membrane basale se produisait. Ces resultats suggerent que l'activite proteinase neutre generee par les cellules derivees du mesangium pourraient jouer un role dans le renouvellement physiologique des proteines de la structure glomerulaire in vivo.
Studies on the hepatomegaly caused by the hypolipidemic drugs nafenopin and clofibrate

Abstract Clofibrate (ethyl- p -chlorophenoxyisobutyrate) and nafenopin (2 methyl-2-( p -(1,2,3,4-tetrahydro-1-naphthyl) phenoxy)-propionate), structurally similar hypolipidemic phenolic ethers, were given po to adult male mice at 25 or 100 mg/kg/day once daily for 7 or 14 consecutive days. Both compounds increased liver weights; however, on a milligram basis nafenopin was 6 to 7 times as potent as clofibrate. Light microscopic exmination of livers from treated mice indicated that with both drugs hepatocytes in the centrilobular area were swollen, of finer cytoplasmic granularity and contained somewhat more acidophilic staining material. The microsomal drug-metabolizing enzymes of the smooth endoplasmic reticulum were not markedly affected by drug pretreatment. Hypertrophy of hepatocytes seems a reasonable explanation for the modest increase in liver size following treatment with clofibrate; however, this mechanism would seem inadequate to explain totally the very marked hepatomegaly seen with nafenopin. Measurements of hepatic DNA content after 1 and 2 wk treatment with 100 mg/kg/day of nafenopin showed approximately 30 and 50% increases, respectively, in the DNA content of the total liver. Apparently the hepatomegaly resulting from treatment with nafenopin is explained by an increase in hepatocyte cell number in addition to increases in hepatocyte size.
A biotin-containing compound N-(2-aminoethyl)biotinamide for intracellular labeling and neuronal tracing studies: comparison with biocytin.

The hydrochloride salt of a new, small molecular weight (M.W. = 286) biotin-containing compound referred to as biotinamide (N-(2-aminoethyl)biotinamide) was compared with biocytin (M.W. = 372) for its use in intracellular labeling of neurons and in neuronal tracing experiments using avidin conjugates for histochemical detection. The DC resistance and current passing ability of electrodes filled with 1-2 M potassium chloride, potassium acetate or potassium methylsulfate and containing 1-4% of these compounds were compared. Although differences were observed due to the electrolyte, with KCl electrodes being the least resistant, no electrode differences could be attributed to the concentration or type of tracer. However, whereas biocytin could be electrophoresed with either positive or negative current with roughly similar facility, biotinamide was selectively ejected with positive current. This would be beneficial to electrophysiologists using hyperpolarizing current to stabilize the membrane potential of neurons prior to recording. In addition, biotinamide-HCl could be dissolved at concentrations of 2-4% in either 1 or 2 M salt without precipitation, whereas biocytin precipitated in some of these solutions. Both compounds were equally useful for neuronal tracing experiments with survival times of 2 days, but labeling was much weaker with longer survival times. There was also little difference in the ability to histochemically localize these compounds using avidin conjugates, including avidin-biotin-horseradish peroxidase complex. In conclusion, biotinamide shares many of the useful features of biocytin, but can be selectively electrophoresed with positive current and can be dissolved at higher concentrations with little detriment in the electrical properties of the recording electrode.
Anisotropic Processing of Laser Speckle Images Improves Spatiotemporal Resolution

Laser speckle contrast imaging (LSCI) is a full field optical imaging technique, capable of imaging blood flow without the introduction of any exogenous dyes. Spatial and temporal resolution in LSCI images depend on how pixels are chosen from the raw image stack for contrast processing. However, all processing schemes are based on isotropic treatment of the spatial neighborhood about each pixel, restricting further improvement in spatiotemporal resolution and image quality. We present a novel spatiotemporal processing scheme for LSCI where the spatial neighborhood is anisotropic, that is, restricted along a specific direction that matches direction of blood flow. The technique allows for a significant increase in temporal resolution, from conventionally used 40 or 80 frames to just three frames; while simultaneously achieving 23% and 47% higher signal-to-noise ratios over concurrent spatiotemporal schemes, when imaging rapid and slow functional changes in blood flow, respectively. We present the concept, justification, and performance evaluation of the novel scheme and demonstrate its suitability for imaging rapid changes in blood flow. Anisotropic LSCI was able to monitor the heart rate associated fluctuations in intravascular blood flow and showed them to be as high as 28% of the mean.
A comparison of single breath and re-breathe diffusing capacity in emphysema patients and controls.

Abstract In emphysema patients, gas dilutional alveolar volume is underestimated by a 10 s single breath maneuver at total lung capacity (TLC) compared with re-breathing at functional residual capacity (FRC); corresponding underestimation of single breath diffusing capacity (DLCO) in emphysema has not been demonstrated. The purpose of this study was to quantify the degree to which re-breathe DLCO at FRC (DLCORB) differs from single breath DLCO at TLC (DLCOSB) in emphysema. In 37 consecutively recruited patients with moderate to severe emphysema (FEV1/FVC 40% ± 10% predicted), DLCORB as % predicted of 91 controls without cardiopulmonary disease was 79% ± 24%, significantly greater than % predicted DLCOSB (44% ± 19%; p These data indicate that a 10 s single breath DLCO maneuver progressively under-represents re-breathe lung diffusing capacity in emphysema as airflow obstruction increases.
Comparison of Descriptor Spaces for Chemical Compound Retrieval and Classification

In recent years the development of computational techniques that build models to correctly assign chemical compounds to various classes or to retrieve potential drug-like compounds has been an active area of research. Many of the best-performing techniques for these tasks utilize a descriptor-based representation of the compound that captures various aspects of the underlying molecular graph?s topology. In this paper we compare different set of descriptors that are currently used for chemical compound classification. In this process, we also introduce four different descriptors derived from all connected fragments present in the molecular graphs. In addition, we introduce an extension to existing vector-based kernel functions to take into account the length of the fragments present in the descriptors. We experimentally evaluate the performance of the previously introduced and the new descriptors in the context of SVM-based classification and ranked-retrieval on 28 classification and retrieval problems derived from 18 datasets. Our experiments show that for both these tasks, the new descriptors consistently and statistically outperform previously developed schemes based on the widely used fingerprint- and Maccs keys-based descriptors, as well as recently introduced descriptors obtained by mining and analyzing the structure of the molecular graphs.
Imperialism and Racial Geography in James Henry Breasted’s Ancient Times, a History of the Early World

Abstract James Henry Breasted (1865–1935), founder of the Oriental Institute at the University of Chicago, was a prolific writer of popularizing books on the ancient Near East. This article presents a critical analysis and historical contextualization of one of his most widely read books: Ancient Times, a History of the Early World. Published as a high school textbook in 1916 and revised in 1935, it serves as a reference point from which to investigate the effects of political and cultural variables on ancient historiography. Changes between the first and second editions of the book indicate that Breasted increasingly relied on scientific vocabulary to map the geo-racial boundaries of early civilization. Combining this with a model of enlightened exploitation, Breasted constructed a vision of the ancient past that was ultimately a commentary on the socio-political conditions of his own time.
“War message,” December 8, 1941: An approach to language

Reviewers have pointed to difficulties. Arnold's review of Nichols' work asks for a sample of the criticism "I am exhorted to produce. . . ." He feels that Nichols "does not illustrate in pointed ways how criticism may, in practice, resolve the . . . issues raised. . . ." Responding to Black's work, Ehninger agrees with Black's assessment of much criticism but believes Black's alternatives "are not worked out in enough detail to be viable." The "ingredients . . . are not developed into anything approaching a critical method" nor are "characteristics and possibilities . . . systematized into a program of attack and procedure which the critic . . . may apply." Yet neither Black nor Nichols set out to develop systems. Black observes:
An Approach to Low Footprint Pronunciation Models for Embedded Speaker Independent Name Recognition

Pronunciation modeling is an important component of speaker independent name recognition on embedded devices. Decision trees have been widely used to generate pronunciations of names due to improved accuracy. However, pronunciation modeling using decision trees may suffer from two main draw backs. The first is large memory footprint. The second is that decision trees usually generate a single pronunciation which does not reflect the real-world multiple pronunciations of a name. We present an approach to address these draw backs. The approach consists of a letter-to-phoneme mapping method that prunes many irregular pronunciations in order to train compact decision trees, and a multi-stage pronunciation transformation method that generates multiple pronunciations from the output of the trained decision trees. The approach effectively reduces footprint by more than 58% and achieves more than 23% of word error rate reduction, compared to a baseline.
Decreased ventilation in preterm infants during oral feeding

As respiratory difficulty may accompany nipple feeding in preterm neonates, we studied the effect of oral feeding on ventilation in 23 preterm infants. The infants composed two groups based on their postconceptional age at the time of study: Group A comprised 12 infants 34 to 35.9 weeks of age, and group B, 11 infants 36 to 38 weeks. Ventilation was measured via a nasal mask pneumotachometer, and sucking pressure via a nipple that also permitted milk delivery; transcutaneous P o 2 and P co 2 were continuously monitored. The feeding pattern comprised an initial period of continuous sucking of at least 30 seconds, followed by intermittent sucking bursts for the remainder of the feed. When compared with an initial semi-upright control period, minute ventilation (V1) during continuous sucking fell by 52±6% (P c P o 2 of 13±4 mm Hg (P c P o 2 recovered partially only in the more mature infants (group B). At the end of the feed, T c P co 2 had risen by 3±1 mm Hg (P
An assessment of iodine nutritional status and thyroid hormone levels in children aged 8–10 years living in Zhejiang Province, China: a cross-sectional study

Iodine is an essential nutrient for the synthesis of thyroid hormones that are critical for brain development. Iodine deficiencies were prevalent in China until the introduction of universal salt iodization (USI) in 1995. USI has been considered as the world’s best achievements. This study aims to assess children’s iodine nutrition and goiter status in Zhejiang Province in order to provide reasonable suggestions to the government for policy-making under the USI period. A cross-sectional survey in Zhejiang Province was conducted to children aged 8–10 years by stage cluster random sampling method. Spot urine samples were collected and analyzed. Thyroid ultrasonography examination was performed by special trained technicians using a 7.5-MHz transducer. Fasting venous blood samples were collected and analyzed for thyroid functional status. The median urinary iodine concentration was found to be 173.3 μg/L. The percentage of urine samples with iodine concentration 300 μg/L was 15.5, 42.0, and 13.3 %, respectively. Goiter prevalence rate with iodine concentration 300 μg/L was 6.8, 10.0, and 14.9 %, respectively, with no significant difference. Children with goiter have lower serum FT3 and T3 concentrations compared to those without goiter (p < 0.05). Conclusions: The median urinary iodine concentration of children aged 8–10 years falls in optimal iodine status as recommended by WHO/UNICEF/ICCIDD. Maintaining USI at an appropriate level is an important part of preventing iodine deficiency disorders and should always be based on routine monitoring urinary iodine concentration by the province.
Adenotonsillectomy for Obstructive Sleep Apnea in Obese Children

OBJECTIVE: To study changes in sleep behavior and quality of life in obese children after adenotonsillectomy for obstructive sleep apnea.STUDY DESIGN AND SETTING: Prospective study at the Universit...
DYNAMICS OF INTERMITTENT STREAM HABITAT REGULATE PERSISTENCE OF A THREATENED FISH AT MULTIPLE SCALES

Traditionally, threatened species management has emphasized conservation of individual populations and has assumed that abundance within suitable habitats is primarily governed by local environmental factors. However, recent research has revealed that landscape-level processes such as disturbance, dispersal, and habitat patch mosaic structure may also strongly influence local populations. We studied the population and habitat dynamics of a threatened fish, the Arkansas darter (Etheostoma cragini) at four spatial scales (pool, reach, segment, watershed) in two intermittent Colorado plains streams. At each scale, information on hydrology, habitat, and fish populations was combined to evaluate factors influencing darter persistence. At the pool scale, Arkansas darters persisted in most permanent pools during summer drought, tolerated extremes of hyperthermia and hypoxia, and were extirpated only when pools dried. Deeper pools had a higher probability of persisting during summer drought. At the reach scale, s...
A MODEL THEORY FOR PROPOSITIONAL ATTITUDES

My chief aim has been to convey the thought that the application of model theoretic techniques to natural languages needn't force a distortion of intentional phenomena. I hope that at least I have succeeded in accomplishing this.
DETERMINANTS OF INNOVATIVE BEHAVIOR: A PATH MODEL OF INDIVIDUAL INNOVATION IN THE WORKPLACE

The present study integrated a number of streams of research on the antecedents of innovation to develop and test a model of individual innovative behavior. Hypothesizing that leadership, individual problem-solving style, and work group relations affect innovative behavior directly and indirectly through their influence on perceptions of the climate for innovation, we used structural equation analysis to test the parameters of the proposed model simultaneously and also explored the moderating effect of task characteristics. The model explained approximately 37 percent of the variance in innovative behavior. Task type moderated the relationship between leader role expectations and innovative behavior.
Temporal actions of 16α-hydroxyestrone in the rat: Comparisons of lordosis dynamics with other estrogen metabolites and between sexes

16α-Hydroxyestrone (160HE1), a metabolite of estradiol (E2) and precursor of estriol (E3), binds to the estrogen receptor (ER) with low affinity (3% of E2), but is estrogenic in both in vitro and in vivo systems. This metabolite is able to bind in a non-dissociable manner to the ER. We examined these properties in vivo by assessing the temporal dynamics of estrogen metabolite action in the rat brain, using lordosis score (LS) to manual stimulation as a serial bioassay of estrogen effect. Male and female castrate Fisher rats were implanted with osmotic minipumps containing either vehicle, E2, 160HE1, or E3. 160HE1-induced LS was delayed in onset in both sexes relative to E2 and E3. Male LS reached a similar plateau for all metabolites, whereas female LS reached an initial LS plateau similar in amplitude to the male plateau. Over the next several days, female LS increased to reach a secondary plateau of higher amplitude, which persisted until pump removal. Upon pump removal, E2- and E3-stimulated LS fell to baseline quickly in both sexes, whereas 160HE1-stimulated LS in males demonstrated a prolongation of maximal LS for 6 days following pump removal. These results suggest that 160HE1 is estrogenic in the brains of both sexes. The delay of onset of LS with 160HE1 is consistent with its poor ER affinity. Females were able to augment LS with prolonged exposure to all metabolites, while males could not. The ability of 160HE1 to maintain maximal LS in the male long after its withdrawal is consistent with its ability to bind non-dissociably to the ER and promote prolonged estrogenic activation. However, females do not exhibit this response, suggesting a sex specificity in the dynamics of ligand-receptor action in the rat brain.
Auger Analysis of Hot‐Pressed and Sintered Silicon Carbide

Intergranular and transgranular chemistries of hot-pressed and sintered silicon carbides were investigated by Auger electron spectroscopy. Results indicated major differences in grain-boundary compositions between the two. Hot-pressed silicon carbide displayed a complex intergranular chemistry. Sintered silicon carbide displayed grain facets that were free of impurities and additives. The observed intergranular chemistries for both silicon carbides are discussed in terms of their relation to the processing methods.
Conformal invariance and conservation laws for relativistic wave equations for zero rest mass

It is shown that the relativistic wave equations obtained byGarding for particles of zero rest mass and arbitrary spin are invariant under the conformal transformations of space-time. Conservation laws corresponding to this invariance are obtained. They are formally identical with those found by Bessel-Hagen for the electromagnetic field, with the exception of those found for the scalar field. For this case, the conservation laws contain extra terms which arise from the fact that the trace of the energy-momentum tensor is not zero.
Raising a New Generation of Empowered Nurses in Maternal–Child Health

Newborn Care Poster Presentation Purpose for the Program To encourage undergraduate nursing students to think about nursing from a global perspective and explore the needs of underserved childbearing women. Furthermore, to introduce students to scholarly writing for professional presentations or publications. Proposed Change Typically, undergraduate nursing students who take courses for honors credit write a literature review or give a presentation to peers/clinical staff on a particular topic germane to the class. Though these exercises are valuable, they do not challenge the students to think about nursing from a global perspective, nor do they require them to write at a professional level worthy of publication/presentation. This program encouraged students to choose a topic related to the health care of underserved childbearing women in the United States and across the globe. Each student chose a different topic and met with the instructor on a regular basis to complete a scholarly paper and an abstract that could be submitted to a professional nursing organization. Implementation, Outcomes, and Evaluation Students who enrolled in a maternal–child nursing course decided on a project that would enhance their understanding from a global perspective of the nursing implications for underserved childbearing populations. Students were asked to share resources and findings as they conducted literature reviews for their papers. The students wrote a 200‐word abstract and the combined instructor–student effort resulted in the submission of the abstract for presentation at an international nursing conference. Students chose challenging topics. Some of these topics included nursing care of pregnant women, incarcerated women, health implications during pregnancy, delivery for immigrant woman with genital mutilation, nursing considerations for the families with surrogate pregnancies in the United States and Europe, and care of homeless pregnant women in the United States and Europe. Students had never written an abstract before this class, but were successful with coaching. The abstract submitted by the instructor/student team to the international conference of Sigma Theta Tau was accepted as a poster presentation. Implications for Nursing Practice This program demonstrates that undergraduate nursing students are able to perform scholarly activities that add to nursing knowledge before the official start of their nursing careers. Early guidance and encouragement may lead to novice nurses who are eager to join and contribute to a global nursing community.
Topic‐sensitive search engine evaluation

Purpose – This work aims to investigate the sensitivity of ranking performance with respect to the topic distribution of queries selected for ranking evaluation.Design/methodology/approach – The authors reweight queries used in two TREC tasks to make them match three real background topic distributions, and show that the performance rankings of retrieval systems are quite different.Findings – It is found that search engines tend to perform similarly on queries about the same topic; and search engine performance is sensitive to the topic distribution of queries used in evaluation.Originality/value – Using experiments with multiple real‐world query logs, the paper demonstrates weaknesses in the current evaluation model of retrieval systems.
Preparation of high performance poly(ethylene terephthalate) fibers: two-stage drawing using high pressure CO2

Abstract Poly(ethylene terephthalate) fibers were drawn in CO2 (liquid) at 23°C above the critical pressure followed by a second stage draw ≥200°C in air. We investigated the effects of first stage morphology on the second stage drawability and properties of the resultant fibers after the second stage. At 200°C, the maximum achievable draw ratios (DRmax) for the CO2 treated and untreated original fibers were 12.2 and 8.2, respectively. The CO2 treated fibers had 10% higher strength and modulus values. In addition, the CO2 treated fibers showed slightly higher birefringence and crystallinity values. At higher draw temperatures, the fibers had high crystallinity values (>60%). However, the amorphous chain orientation was much lower. The high drawability of the PET drawn in CO2 can be explained by the plasticization of the polymer where CO2 aids in the disentanglement of the polymer chains during the drawing process. This CO2 morphology results in a very ductile structure compared to untreated fibers.
Aquaglyceroporin 9 in brain pathologies

Aquaglyceroporins belong to the aquaporin family and are permeable to water and also to small solutes such as glycerol and urea. In this review, we will compare the expression of aquaporin 9 (AQP9), an aquaglyceroporin, with that of AQP4, a pure water channel, in pathological conditions. In astrocytes, AQP4 is mainly involved in water and ionic homeostasis. Its expression is highly modified in several brain disorders and it plays a key role in cerebral edema formation. AQP9 is expressed in astrocytes and in catecholaminergic neurons. The level of expression of brain AQP9 is under the control of blood insulin concentrations, and its expression is increased in diabetes, suggesting that AQP9 could be involved in brain energy metabolism. The induction of AQP9 in astrocytes is observed over time after stroke onset, suggesting participation in the clearance of excess lactate in the extracellular space. In some models, AQP9 is also induced in non-catecholaminergic neurons after global ischemia and in the periphery of gliomas, however functional roles are still unclear. The review of literature underlies that each AQP has several distinctive roles which depend on the AQP and cell types.
Effect of roasted soybeans and corn on performance and ruminal and blood metabolites of dairy calves.

Abstract Newborn Holstein calves (n = 132) were used to evaluate three protein sources (soybean meal and soybeans roasted to an exit temperature of 138 or 146°) that contained 30, 45, or 52% RUP, respectively. Each was used with either raw corn or corn roasted to an exit temperature of 135°. Roasting of corn increased starch gelatinization from 34.8 to 118.6mg of maltose equivalents/g of sample. Six pelleted isonitrogenous calf starters (18% CP) were fed for ad libitum consumption from 0.5 to 8 wk of age. Performance of calves fed soybeans roasted at 146° plus raw corn was superior to that of calves fed soybean meal plus raw corn but was similar to the performance of calves fed soybean meal plus roasted corn. Roasted corn tended to improve calf performance when used with soybean meal and, to a lesser degree, when used with soybeans roasted at 138° but depressed performance when used with soybeans roasted at 146°c Ruminal concentrations of NH 3 , butyrate, and total VFA and plasma concentrations of urea were higher for calves fed soybean meal. Ruminal pH and lactate, plasma NEFA, and blood BHBA concentrations were unaffected by starter. Performance was superior when calves consumed protein and corn sources with similar degrees of ruminal availability.
On the validity of polarization and correlation additivity in Ab Initio molecular orbital calculations

A common approximation used in ab initio molecular orbital calculations assumes that the changes in energy due to use of a larger basis set (as in the inclusion of polarization orbitals) and to allowance for electron correlation are additives. Thus, small basis sets may be used for correlated ab initio calculations, resulting in a great savings in time. While this approach has been shown to perform acceptably in some cases, a systematic study has not been published. We examined 35 species and computed the heats of reaction for 15 processes at the 6-31G level of theory using polarization and correlation correction up to the MP4 level. The same items were then treated by an additive procedure to attain the same level of theory. We also examined the conrotrary ring opening of cyclobutene. Our results indicate that the errors do cancel to some extent but that the uncertainty associated with open shell species is significantly larger than closed shell systems. This calls into question the use of the procedure in predicting the properties of transition states.
The Intestinal Microbiota and Viral Susceptibility

Many infections start with microbial invasion of mucosal surfaces, which are typically colonized by a community of resident microbes. A growing body of literature demonstrates that the resident microbiota plays a significant role in host susceptibility to pathogens. Recent work has largely focused on the considerable effect that the intestinal microbiota can have upon bacterial pathogenesis. These studies reveal many significant gaps in our knowledge about the mechanisms by which the resident community impacts pathogen invasion and the nature of the ensuing host immune response. It is likely that as viral pathogens become the focus of studies that examine microbiota-host interaction, substantial effects of resident communities exerted via diverse mechanisms will be elucidated. Here we provide a perspective of the exciting emerging field that examines how the intestinal microbiota influences host susceptibility to viruses.
An Empirical Backbone−Backbone Hydrogen-Bonding Potential in Proteins and Its Applications to NMR Structure Refinement and Validation

A new multidimensional potential is described that encodes for the relative spatial arrangement of the peptidyl backbone units as observed within a large database of high-resolution X-ray structures. The detailed description afforded by such an analysis provides an opportunity to study the atomic details of hydrogen bonding in proteins. The specification of the corresponding potential of mean force (PMF) is based on a defined set of physical principles and optimized to yield the maximum advantage when applied to protein structure refinement. The observed intricate differences between hydrogen-bonding geometries within various patterns of secondary structure allow application of the PMF to both validation of protein structures and their refinement. A pronounced improvement of several aspects of structural quality is observed following the application of such a potential to a variety of NMR-derived models, including a noticeable decrease in backbone coordinate root-mean-square deviation relative to the X-ray structures and a considerable improvement in the Ramachandran map statistics.
Electroencephalographic, behavioral, and single-unit effects produced by stimulation of forebrain inhibitory structures in cats

Abstract The neuronal basis of EEG synchronization, sleep, and behavioral inhibition was studied in cats prepared chronically for forebrain stimulation and single-unit and EEG recording. Low-frequency stimulation to the orbital cortex, caudate nucleus, and the basal forebrain region all produced EEG synchronization and inhibition of ongoing operant behavior. Thresholds for behavioral inhibition were close to or slightly higher than thresholds for EEG synchronization. Cells in the cortex, thalamus, and hypothalamus were investigated during stimulation of the forebrain sites. There was a frequent parallel between unit effects and EEG slow-wave potentials recorded from the same electrode. A positive-going, slow potential was the usual concomitant of cellular inhibition. The data indicate that the three forebrain inhibitory regions have a convergence of synchronizing influences and that these influences are exerted upon cells sampled from all structures explored. There were no obvious differences in neuronal response as a function of cell location. The range of latencies of unit effects was from 1–24 msec, but in most cases the latencies were 5 msec or less, which suggests that the forebrain-influencing pathways are fairly direct rather than circuitous. It was proposed that the forebrain influences which produce sleep and behavioral inhibition are due not simply to a neuronal shutdown of the reticular-activating system but to direct and widespread effects.
Downlink training codebook design and hybrid precoding in FDD massive MIMO systems

Interest in massive multiple-input multiple-output (MIMO) systems is growing because of their potential ability to improve spectral and energy efficiency. Most prior work on massive MIMO considers TDD operation that relies on channel reciprocity between uplink and downlink channels, whereas most current cellular systems adopt FDD without channel reciprocity. In an FDD mode, downlink channel estimation becomes a challenging issue due to the substantial training overhead that scales with the number of antennas, which can limit the potential gain of massive MIMO systems. To tackle the issue of channel estimation, we consider the design of a training codebook that has a suitable mapping for the training signal patterns in block transmissions under the assumption of a Kaiman filtering framework. We focus on a reduced dimensionality training codebook and transmit precoding design to enable low-complexity system configuration. We discuss how this framework can extend to hybrid analog-digital precoding using a limited number of active RF chains for transmit beamforming by applying the Toeplitz distribution theorem to large-scale linear antenna arrays. A practical guideline for training codebook parameters is presented, and numerical results show the effectiveness of the proposed algorithm.
Abstract 4952: Study of mouse tumor models with an IRDye 800CW SNAP-tag imaging probe

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Non-invasive optical analysis of molecular targets inside living animals has become an important tool for disease progression and treatment assessment. One of the essential elements of molecular imaging is the development of specific, sensitive imaging contrast agents to investigate these biological processes. The use of longer wavelength dyes, i.e. near-infrared (NIR) dyes, presents distinct advantages over inherently fluorescent protein tags, including reduced autofluorescence background and increased sensitivity in imaging small animals. In addition, the adoption of efficient and specific labeling techniques is a key step in the generation of protein-based fluorescent imaging agents. In the present study, we explore the versatility of a self-labeling protein termed SNAP-tag, derived from human O6-alkylguanine-DNA alkyltransferase, in tagging polypeptides with a near-infrared dye, IRDye® 800CW. In cell-based assays, an IRDye 800CW conjugated SNAP-tag successfully labeled cells transiently transfected with a pSNAP-ADRB2 plasmid. For in vivo experiments, a synthetic epidermal growth factor receptor (EGFR)-binding ligand was used to construct an IRDye 800CW-EGFR-SNAP-tag. Following injection of the agent into nude mice bearing EGFR-overexpressing A431 xenografts, tumors were clearly visualized with a Pearl® Imaging system. Furthermore, the specificity of binding was demonstrated in competition experiments with unlabeled EGF. Similar probes labeled with visible fluorophores were used to image EGFR-expressing cultured cells by confocal microscopy. This fluorescent imaging system using a self-labeling protein tag and highly sensitive organic dyes provides versatile tools for cancer research, drug discovery and small animal imaging. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4952.
Fatigue characteristics of high performance fiber-reinforced concrete

Abstract This paper provides a summary of a study on fatigue behavior undertaken as part of SHRP project C-205 on the fresh and hardened properties of high early strength fiber-reinforced concrete (HESFRC). HESFRC was defined as achieving a minimum target compressive strength of 5 ksi (35 MPa) in 24 h. Several properties of HESFRC were investigated: for the fresh mixture, the air content, inverted slump test, temperature, and unit weight; for the hardened composite, the compres-Sive, bending, and tensile properties. Optimum mixtures that satisfied the minimum compressive strength criterion, and showed excellent values of modulus of rupture, toughness indices in bending, and split tensile behavior, were selected for fatigue testing. In this paper a description is given of key results of the fatigue bending tests only. The experimental program included a total of 24 fiber-reinforced concrete flexural specimens, ten of which were control specimens tested under static flexural loading, and the remaining 14 specimens were tested under fatigue loading. Two mixes containing 2 vol% of hooked steel fibers were selected. For each mix, three different target load ranges were applied: 10–70%, 10–80%, and 10–90% of the ultimate flexural capacity, as obtained from the corresponding control static test with fibers. A typical relation between maximum fatigue stress and number of cycles to failure was derived, suggesting a fatigue endurance limit of the order of 65% even if specimens are in a cracked state.
Preparative gel electrophoresis of liver polyribosomal RNA.

Abstract By the use of a combination of sucrose density gradient centrifugation and low-percent polyacrylamide gel preparative electrophoresis, we have isolated RNA species associated with rat liver polyribosomes and especially that of the 40S ribosomal subunit. Because of the high resolution of preparative polyacrylamide gel electrophoresis, it was found necessary to incorporate 0.5% sodium dodecyl sulfate into the electrophoresis buffer to eliminate artifacts that arise from aggregation of RNA species. This technique would allow the study of subtle changes in presumptive mRNA synthesis and template efficacy in various systems.
Electron microscopy of spread maize pachytene synaptonemal complexes

The Counce-Meyer microspreading technique for animal synaptonemal complexes (SCs) has been adapted to allow spreading of the SCs of maize pachytene microsporocytes for examination in the electron microscope (EM). The spread nuclei were well dispersed and flattened, and unstained SCs could be seen with light microscope (LM) phase optics. After PTA or ammoniacal silver staining, the SCs and kinetochores were readily recognized in the EM. Variable degrees of asynapsis, stretching of the SCs, and nonhomologous synapsis of lateral elements were noted, and cases of interlocking of lateral elements or SCs were not uncommon. Distinct lens-shaped thickenings of one or both lateral elements were observed at numerous sites along the SC in most nuclei. — The yield of well spread, complete nuclei, although not high, was sufficient to allow karyotypes to be prepared, based on relative SC lengths and arm ratios. The karyotypes agreed well with published EM and LM determinations, establishing the accuracy of the spreading technique for maize. However, considerable variation in absolute lengths of the SCs was noted. To evaluate the utility of the technique for cytogenetic investigations, two paracentric inversions, and two reciprocal translocations were spread and examined in the EM. The breakpoints estimated from measurements of spread SCs were in agreement with LM determinations.
Automated Real-Time Classification and Decision Making in Massive Data Streams from Synoptic Sky Surveys

The nature of scientific and technological data collection is evolving rapidly: data volumes and rates grow exponentially, with increasing complexity and information content, and there has been a transition from static data sets to data streams that must be analyzed in real time. Interesting or anomalous phenomena must be quickly characterized and followed up with additional measurements via optimal deployment of limited assets. Modern astronomy presents a variety of such phenomena in the form of transient events in digital synoptic sky surveys, including cosmic explosions (supernovae, gamma ray bursts), relativistic phenomena (black hole formation, jets), potentially hazardous asteroids, etc. We have been developing a set of machine learning tools to detect, classify and plan a response to transient events for astronomy applications, using the Catalina Real-time Transient Survey (CRTS) as a scientific and methodological testbed. The ability to respond rapidly to the potentially most interesting events is a key bottleneck that limits the scientific returns from the current and anticipated synoptic sky surveys. Similar challenge arise in other contexts, from environmental monitoring using sensor networks to autonomous spacecraft systems. Given the exponential growth of data rates, and the time-critical response, we need a fully automated and robust approach. We describe the results obtained to date, and the possible future developments.
Activity costing: twenty years on

This paper reports on a review of the extent to which the activity costing model ( Activity Costing and Input–Output Accounting , G. J. Staubus) has been accepted in practice and in accounting education. Activity costing is a model of cost accounting in which the objects of costing are activities instead of products, e.g. the process of making a product rather than the product made. It incorporates a fundamental economic definition of cost, emphasizes the cost of using resource inputs, recognizes each significant resource rather than three cost elements, treats increments in activity as objects of costing and costs those increments, and attends to asset holding costs and the costs of using plant assets. Evidence of acceptance of those ideas varies from moderate to none. The method called ‘activity-based costing’ can be interpreted as a rejection of the conventional treatment of overhead in favor of identifying specific services (resources) being put into the processes (activities) being costed. Also, a bit of acceptance of the idea that materials holding costs should be loaded onto materials acquisition costs is found. Otherwise, activity costing has not been a great success in the ‘market place’. The unhelpful explanation for lack of acceptance of activity costing is that ‘consumers’ perceptions of the prospective costs and benefits of adopting activity costing have been weighted more heavily on the cost side. Further inquiry has identified several types of costs: direct costs of operating the cost system (or two cost systems), cognitive and educational costs, emotional costs, and dislike of the results because the model yields higher and more variable costs than conventional costing.
Mars atmospheric phenomena during major dust storms, as measured at surface

Meteorological instrumentation aboard the Viking Mars Landers measures wind, temperature, and pressure. Two global dust storms occurred during northern autumn and winter, observed both by the orbiters and by the landers. The meteorological data from the landers has been analyzed for the period just before first storm arrival to just after second storm arrival, with the objectives of defining the meteorological phenomena during the storm period, determining those associated with storm and dust arrival, and evaluating the effects on synoptic conditions and the general circulation. Times of dust arrival over the sites could be defined fairly closely from optical and pressure (solar tide) data, and dust arrival was also accompanied by changes in diurnal temperature range, temperature maxima, and temperature minima. The arrivals of the storms at Viking Lander 1 were accompanied by significant increases in wind speed and pressure. No such changes were observed at Viking Lander 2. It is possible that surface material could have been raised locally at Viking Lander 1. Throughout the period except for the time following the second dust storm the synoptic picture at Viking Lander 2 was one of eastward moving cyclonic and anticyclonic systems. These disappeared following the second storm, a phenomenon which may be related to the storm.
Robust incentive techniques for peer-to-peer networks

Lack of cooperation (free riding) is one of the key problems that confronts today's P2P systems. What makes this problem particularly difficult is the unique set of challenges that P2P systems pose: large populations, high turnover, a symmetry of interest, collusion, zero-cost identities, and traitors. To tackle these challenges we model the P2P system using the Generalized Prisoner's Dilemma (GPD),and propose the Reciprocative decision function as the basis of a family of incentives techniques. These techniques are fullydistributed and include: discriminating server selection, maxflow-based subjective reputation, and adaptive stranger policies. Through simulation, we show that these techniques can drive a system of strategic users to nearly optimal levels of cooperation.
A parallel scalable infrastructure for OLAP and data mining

Decision support systems are important in leveraging information present in data warehouses in businesses like banking, insurance, retail and health care. The multidimensional aspects of a business can be naturally expressed using a multidimensional data model. Data analysis and data mining on these warehouses pose new challenges for traditional database systems. OLAP and data mining operations require summary information on these multidimensional data sets. Query processing for these applications require different views of data for analysis and effective decision making. Data mining techniques can be applied in conjunction with OLAP for an integrated business solution. As data warehouses grow, parallel processing techniques have been applied to enable the use of larger data sets and reduce the time for analysis, thereby enabling evaluation of many more options for decision making. We address: (1) scalability in multidimensional systems for OLAP and multidimensional analysis; (2) integration of data mining with the OLAP framework; and (3) high performance by using parallel processing for OLAP and data mining. We describe our system PARSIMONY-Parallel and Scalable Infrastructure for Multidimensional Online analytical processing. This platform is used both for OLAP and data mining. Sparsity of data sets is handled by using sparse chunks using a bit encoded sparse structure for compression. Techniques for effectively using summary information available in data cubes for data mining are presented for mining association rules and decision tree based classification. These take advantage of the data organization provided by the multidimensional data model. Performance results for high dimensional data sets on a distributed memory parallel machine (IBM SP-2) show good speedup and scalability.