cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling the Kinetics of Integrin Receptor Binding to Hepatic Extracellular Matrix Proteins

The composition of the extracellular matrix (ECM) proteins and the expression of their cognate receptors dictate cell behavior and dynamics. In particular, the interactions of ECM proteins with integrin receptors are key mediators of these cellular processes, playing a crucial role in the progression of several diseases of the liver, including inflammation, fibrosis/cirrhosis and cancer. This study establishes a modeling approach combining computation and experiments to evaluate the kinetics of integrin receptor binding to hepatic ECM proteins. ECM ligand concentration was derived from LC-MS/MS quantification of the hepatic ECM from mice exposed to chronic carbon tetrachloride (CCl4); receptor density was derived from published literature. Mathematical models for ECM-integrin binding kinetics that were developed incorporate receptor divalence and an aggregation scheme to represent clustering. The computer simulations reproduced positive cooperativity in the receptor aggregation model when the aggregation equilibrium constant (Ka) was positive and greater than Keq for divalent complex formation. Importantly, the modeling projected an increase in integrin binding for several receptors for which signaling is known to be increased after CCl4 exposure in the liver. The proposed modeling approach may be of use to elucidate the kinetics of integrin receptor binding to ECM proteins for homeostatic and diseased livers.
Pharmacological Therapies for Hepatorenal Syndrome: A Systematic Review and Meta-Analysis

Background:Hepatorenal syndrome (HRS) is a serious complication of advanced chronic liver disease. Different pharmacological therapies have variable efficacy. We performed a systematic review and meta-analysis to compare the efficacy of various drugs in the treatment of HRS.Study:Randomized controll
Supplementing Modern Software Defenses with Stack-Pointer Sanity

The perpetual cat-and-mouse game between attackers and software defenders has highlighted the need for strong and robust security. With performance as a key concern, most modern defenses focus on control-flow integrity (CFI), a program property that requires runtime execution of a program to adhere to a statically determined control-flow graph (CFG). Despite its success in preventing traditional return-oriented programming (ROP), CFI is known to be ineffective against modern attacks that adhere to a statically recovered CFG (e.g., COOP). This paper introduces stack-pointer integrity (SPI) as a means to supplement CFI and other modern defense techniques. Due to its ability to influence indirect control targets, stack pointer is a key artifact in attacks. We define SPI as a property comprising of two key sub-properties - Stack Localization and Stack Conservation - and implement a LLVM-based compiler prototype codenamed SPIglass that enforces SPI. We demonstrate a low implementation overhead and incremental deployability, two of the most desirable features for practical deployment. Our performance experiments show that the overhead of our defense is low in practice. We opensource SPIglass for the benefit of the community.
Designing well-defined photopolymerized synthetic matrices for three-dimensional culture and differentiation of induced pluripotent stem cells

Induced pluripotent stem cells (iPSCs) are of interest for the study of disease, where these cells can be derived from patients and have the potential to be differentiated into any cell type; however, three-dimensional (3D) culture and differentiation of iPSCs within well-defined synthetic matrices for these applications remains limited. Here, we aimed to establish synthetic cell-degradable hydrogels that allow precise presentation of specific biochemical cues for 3D culture of iPSCs with relevance for hypothesis testing and lineage-specific differentiation. We synthesized poly(ethylene glycol)-(PEG)-peptide-based hydrogels by photoinitiated step growth polymerization and used them to test the hypothesis that the viability of iPSCs within these matrices could be rescued with appropriate biochemical cues inspired by proteins and integrins important for iPSC culture on Matrigel. Specifically, we selected a range of motifs inspired by iPSC binding to Matrigel, including laminin-derived IKVAV and YIGSR, α5β1-binding PHSRNG10RGDS, αvβ5-binding KKQRFRHRNRKG, and RGDS that is known to bind a variety of integrins for generally promoting cell adhesion. YIGSR and PHSRNG10RGDS resulted in the highest iPSC viability, where binding of β1 integrin was key, and these permissive compositions also allowed iPSC differentiation into neural progenitor cells (NPCs) (decreased oct4 expression and increased pax6 expression) in response to soluble factors. The resulting NPCs formed clusters of different sizes in response to each peptide, suggesting that matrix biochemical cues affect iPSC proliferation and clustering in 3D culture. In summary, we have established photopolymerizable synthetic matrices for the encapsulation, culture, and differentiation of iPSCs for studies of cell-matrix interactions and deployment in disease models.
Regeneration of the Olfactory Epithelium

The peripheral olfactory system can overcome damage to the olfactory epithelium or transection of the olfactory nerve to reform connections with the olfactory bulb (OB) and restore function, even into adulthood. That capacity reflects the persistence throughout life and lesion-induced activation of neurocompetent stem and progenitor cells that repopulate the epithelium with nascent neurons, as well as nonneuronal cells, as needed. Thus, following epithelial lesion (e.g., that caused by exposure to the olfactotoxin, methyl bromide (MeBr)) the sensory neurons are reconstituted in full, or nearly so, with precise restoration of the spatial patterning of odorant receptor (OR) expression. Of the cell types within the epithelium, the globose basal cells (GBCs) are critical to that recovery process. Moreover, the GBCs are a functionally heterogeneous group and among them are found progenitors that are broadly multipotent as well as others that give rise to neurons only. The expression of various transcription factors (TFs) apparently correlate with the differences in functional capacity. Reinnervation of the OB is robust, particularly after epithelial damage. However, the reformed connections show some degree of mistargeting: if only the epithelium has been damaged, axons tend to reconnect with the same region of the bulb, down to the level of the patch of glomeruli within which the target glomerulus is normally found (rhinotopy and receptotopy are restored). However, the axons may fail to converge onto a single glomerulus (glomerulotopy is not restored). In contrast, the reinnervation that follows nerve transection is accompanied by more substantial mistargeting. Despite these errors, substantial olfactory function is restored, although odorant encoding is apparently distorted as in humans following recovery from damage to the periphery. In the future, attention will turn to more detailed understanding of the various functionally defined classes of progenitors and their regulation, isolation of the tissue stem cells of the epithelium and efforts to enhance the accuracy and extent of reinnervation of the bulb.
Acute Effects of Antioxidants on in Vivo Models of Experimental Myocardial Ischemia and Infarction

It is well appreciated that early reperfusion of an occluded coronary artery can salvage at least some of the previously ischemic myocardium and thereby reduce the extent of ischemia-induced myocyte injury (1–3). However, it has more recently been suggested that reperfusion is a ‘double-edged sword’ (4): that is, restoration of blood flow may salvage some previously ischemic tissue, yet have deleterious effects on other previously ischemic myocytes.
Development of Object Permanence in Visually Impaired Infants

The development of object permanence skills in 20 visually impaired infants between the ages of 4 and 25 months was examined longitudinally. Other areas of development which were examined in relati...
Implementation of individualized care plans in high risk oncology patients: A team based model to decrease unnecessary utilization.

6547Background: Due to complexity of disease and treatments, oncology patients (pts) have among the highest hospitalization rate. In our cancer institute, just 6% of all discharged pts accounted fo...
Two-Level Quantum Systems in Two-Dimensional Materials for Single Photon Emission

Single photon emission (SPE) by a solid-state source requires presence of a distinct two-level quantum system, usually provided by point defects. Here we note that a number of qualities offered by novel, two-dimensional materials, their all-surface openness and optical transparence, tighter quantum confinement, and reduced charge screening-are advantageous for achieving an ideal SPE. On the basis of first-principles calculations and point-group symmetry analysis, a strategy is proposed to design paramagnetic defect complex with reduced symmetry, meeting all the requirements for SPE: its electronic states are well isolated from the host material bands, belong to a majority spin eigenstate, and can be controllably excited by polarized light. The defect complex is thermodynamically stable and appears feasible for experimental realization to serve as an SPE-source, essential for quantum computing, with ReMoVS in MoS2 as one of the most practical candidates.
Toward Utilizing Full-Field Laser-Ultrasound for Practical Nondestructive Inspection with Acoustic Wavenumber Spectroscopy

This study concerns the use of steady, harmonic excitation in place of repeated transient excitation for full-field laser ultrasound inspection. With harmonic excitation, we realized several orders of magnitude improvement in signal level in ultrasonic laser Doppler vibrometer measurements, enabling scans with eye safe lasers on unmodified inspection surfaces at speeds of up to five square meters per minute. We've found that two classes of full-field analysis techniques to be especially effective when properly modified for harmonic response measurements: wavenumber spectroscopy and local gradient estimation. This paper focuses on the former. Wavenumber spectroscopy, which is effective at detecting in-plane defects, involves local analysis of the wavelengths of the ultrasonic waves in order to quantify changes in effective thickness using the Rayleigh-Lamb equations. Using the techniques briefly described in this paper, we achieved effective nondestructive evaluation with scan rates of up to 320 square centimeters per second on metallic samples and 80 square centimeters per second on carbon-fiber-reinforced polymer composites.
Diversity and Abundance of Nonculicid Biting Flies (Diptera) In A Zoo Environment.

ABSTRACT The diversity of nonculicid biting flies was surveyed in Sunset Zoo, Manhattan, KS, by carbon dioxide–baited traps. A total of 8,399 nonculicid biting-fly females representing 32 species a...
An analysis of discontinuous Galerkin methods for the compressible Euler equations: entropy and $$L_2$$ stability

The objective of this article is to characterize the entropy and $$L_2$$ stability of several representative discontinuous Galerkin (DG) methods for solving the compressible Euler equations. Towards this end, three DG methods are constructed: one DG method with entropy variables as its unknowns, and two DG methods with conservative variables as their unknowns. These methods are employed in order to discretize the compressible Euler equations in space. Thereafter, the resulting semi-discrete formulations are analyzed, and the entropy and $$L_2$$ stability characteristics are evaluated. It is shown that the semi-discrete formulation of the DG method with entropy variables is entropy and $$L_2$$ stable. Furthermore, it is shown that the semi-discrete formulations of the DG methods with conservative variables are only guaranteed to be entropy and $$L_2$$ stable under the following assumptions: the entropy projection errors vanish, or the terms containing the entropy projection errors are non-positive. Thereafter, the semi-discrete formulation with entropy variables, and one of the semi-discrete formulations with conservative variables, are discretized in time with an ‘algebraically stable’ Runge–Kutta (RK) scheme. The resulting formulations are fully-discrete and can be immediately applied to practical problems. In this article, they are employed to simulate a vortex propagating for long distances. It is shown that temporal stability is maintained by the DG method with entropy variables, but the DG method with conservative variables exhibits instability.
Spatial Accessibility to Mammography Services in the Lower Mississippi Delta Region States.

Purpose To characterize spatial access to mammography services across 8 Lower Mississippi Delta Region (LMDR) states. These states include the Delta Region, a federally designated, largely rural, and impoverished region with a high proportion of black residents and low mammography utilization rates. Methods Using the enhanced 2-step floating catchment area method, we calculated spatial accessibility scores for mammography services across LMDR census tracts. We compared accessibility scores between the Delta and non-Delta Regions of the LMDR. We also performed hotspot analysis and constructed spatial lag models to detect clusters of low spatial access and to identify sociodemographic factors associated with access, respectively. We obtained mammography facility locations data from the Food and Drug Administration and sociodemographic variables from the American Community Survey and the US Department of Agriculture. Results Overall, there were no differences in spatial accessibility scores between the Delta and non-Delta Regions, though there was some state-to-state variation. Clusters of low spatial access were found in parts of the Arkansas, Mississippi, and Tennessee Delta. Spatial lag models found that poverty was associated with greater spatial access to mammography. Conclusions The lack of identified differences in spatial access to mammography in the Delta and non-Delta Regions suggests that psychosocial or financial barriers play a larger role in lower mammography utilization rates. Identifying clusters of low spatial access to mammography services can help inform resource allocation. Further, our study underscores the value of using coverage-based methods rather than travel time or container measures to evaluate spatial access to care.
Optical and Electrical Properties of Phase Change Materials for High-Speed Optoelectronics

By doping Ge 2 Sb 2 Te 5 phase change material with tungsten, we produce material with improved electrical properties while simultaneously maintaining the optical contrast necessary for light modulation and switching. © 2019 The Author(s)
The next hundred years of growth and convergence

World gross domestic product per capita is forecast to grow at 2.6% annually over the next 100 years. Convergence of less‐developed countries toward output levels of the world frontier accounts for much of the forecast. Projecting recent growth in China and India accounts for much of the forecast convergence. The forecast differs from the earlier literature because the facts of convergence have changed in recent decades. A Markov‐switching model is estimated for each country, allowing each country to switch on or off a path of convergence to the world output frontier. Bayesian estimates of the historical process and posterior forecasts are offered.
Bion’s O and His Pseudo-Mystical Path

The concept of Bion of O is both essential and elusive like few others. By its ambiguous nature it gives rise to the most disconcerting interpretations and many misunderstandings. Among these is th...
Gundy v. U.S. on Delegation of Power

One of the core principles of the US Constitution is separation of powers, the belief that ambition must be counteracted with ambition so that too much authority is not concentrated in the hands of a few. This includes the principle of non-delegation that the powers held by one branch of government must not be given to another, even when done voluntarily. Gundy presents the question of whether Congress gave away too much authority to the Department of Justice to determine who is put on the federal sex offender registry. Does this violate the principle that those who make the laws (Congress) must not also be those who prosecute the offenders (DOJ)? Have those functions been combined in a way that will lead to abuse? Gundy applies to sex offenders, but the principle of non-delegation has become an important question that will influence many future decisions of the Court.
Social/Critical/Emancipatory Accounting Research: Its Failure and Prospects for Redemption

Social, critical, and emancipatory accounting research has been around for a half a century under its various labels. Yet, while it may have achieved some minor victories in its quest for “social justice” and concern for “environmental degradation”, after 50 years it has failed to achieve its ultimate objective—to ultimately change existing social relations, move toward a more equitable social order, and participate in an actual transformation of the system by reforming financial statements by incorporating non-GAAP social costs and benefits into financial statements. The purpose of this paper is first to identify the reasons for the failure of social, critical, and emancipatory accounting research to achieve its ultimate objective. This paper makes a critical analysis of the target of critical accounting research, the field of battle in which it has chosen to engage the target, and the methods it has chosen with which to confront its target. Second, this paper explains what is necessary for SCE accounting research to make progress toward achieving its ultimate objective in order to refocus its energies into research more germane to achieving its ultimate objective and thereby redeem itself from languishing in a state of irrelevancy.
P131 Identifying SNAP Participant Experiences and Environments to Inform Tailored SNAP-Ed Programming

Background The SNAP-Ed program aims to ensure low-income populations are able to meet dietary guidelines through nutrition education and changing policies, systems, and environments (PSE) within diverse settings. Little is known about SNAP participants’ experiences with SNAP-Ed in South Carolina or about their food and activity environments. Objective This study aims to identify SNAP participants’ experiences and environments to inform tailored programming strategies. Study Design, Setting, Participants A telephone survey was conducted with 2,000 randomly-selected SC SNAP participants. Measurable Outcome/Analysis Descriptive analyses were conducted for all survey questions. Results The majority of respondents had not heard of SNAP-Ed (85.5%), and the majority of respondents who had heard of the program had not participated (88.8%). Most respondents procured food from grocery stores (90.2%), big box stores (71.7%), or dollar stores (63.9%). In a typical week, respondents most often visited places to get food (70.8%) or other household items (61.4%), places of worship (59.5%), and health care centers (57.2%). Respondents were most likely to find out about things in their community through television news (72.5%), family and friends (71.7%), and via word of mouth (65.7%). The majority of respondents (74%) were found to be at risk of food insecurity, and 46% of respondents reported that they did not have reliable transportation at some point during the past year. Conclusions SNAP participant responses indicate the need for promoting the program through television news and tapping into social networks; providing programming at food retail outlets, places of worship, and health care centers; and focusing PSE efforts on increasing food security and transportation access. Funding Supplemental Nutrition Assistance Program - Education.
Enhancing cardiovascular research with whole-organ imaging.

Purpose of review There have been tremendous advances in the tools available for surveying blood vessels within whole organs and tissues. Here, we summarize some of the recent developments in methods for immunolabeling and imaging whole organs and provide a protocol optimized for the heart. Recent findings Multiple protocols have been established for chemically clearing large organs and variations are compatible with cell type-specific labeling. Heart tissue can be successfully cleared to reveal the three-dimensional structure of the entire coronary vasculature in neonatal and adult mice. Obtaining vascular reconstructions requires exceptionally large imaging files and new computational methods to process the data for accurate vascular quantifications. This is a continually advancing field that has revolutionized our ability to acquire data on larger samples as a faster rate. Summary Historically, cardiovascular research has relied heavily on histological analyses that use tissue sections, which usually sample cellular phenotypes in small regions and lack information on whole tissue-level organization. This approach can be modified to survey whole organs but image acquisition and analysis time can become unreasonable. In recent years, whole-organ immunolabeling and clearing methods have emerged as a workable solution, and new microscopy modalities, such as light-sheet microscopy, significantly improve image acquisition times. These innovations make studying the vasculature in the context of the whole organ widely available and promise to reveal fascinating new cellular behaviors in adult tissues and during repair.
A Survey on Optimal Transport for Machine Learning: Theory and Applications.

Optimal Transport (OT) theory has seen an increasing amount of attention from the computer science community due to its potency and relevance in modeling and machine learning. It introduces means that serve as powerful ways to compare probability distributions with each other, as well as producing optimal mappings to minimize cost functions. In this survey, we present a brief introduction and history, a survey of previous work and propose directions of future study. We will begin by looking at the history of optimal transport and introducing the founders of this field. We then give a brief glance into the algorithms related to OT. Then, we will follow up with a mathematical formulation and the prerequisites to understand OT. These include Kantorovich duality, entropic regularization, KL Divergence, and Wassertein barycenters. Since OT is a computationally expensive problem, we then introduce the entropy-regularized version of computing optimal mappings, which allowed OT problems to become applicable in a wide range of machine learning problems. In fact, the methods generated from OT theory are competitive with the current state-of-the-art methods. We follow this up by breaking down research papers that focus on image processing, graph learning, neural architecture search, document representation, and domain adaptation. We close the paper with a small section on future research. Of the recommendations presented, three main problems are fundamental to allow OT to become widely applicable but rely strongly on its mathematical formulation and thus are hardest to answer. Since OT is a novel method, there is plenty of space for new research, and with more and more competitive methods (either on an accuracy level or computational speed level) being created, the future of applied optimal transport is bright as it has become pervasive in machine learning.
Service-Learning at an HSI: A Preliminary Analysis

An emerging body of literature seeks to design, implement, and analyze best practices in service learning at undergraduate universities. What scholars have not examined as well is service learning at Hispanic-Serving Institutions (HSI's). Given that students at such universities are in unique learning environments, there is a question of how well standard practices in service learning apply to HSI's. In my paper, I will present my analysis of 2 semesters' worth of service-learning requirements in an Introduction to American Politics course at an HSI in Texas. Using the feedback provided by the students on the final course evaluations, I conclude that the current pedagogy applies reasonably well to HSI’s, but there are certain areas in which pedagogy should be adjusted to reflect the unique aspects of HSI’s, such as accounting for the socioeconomic needs of HSI students.
Acyl-Homoserine Lactone Biosynthesis: Structure and Mechanism

The first quorum-sensing system to be discovered was the Lux system of Vibrio fischeri, which regulates light production in the light organ of deep sea fish and squid via an acyl-homoserine lactone (AHL) signaling molecule. The LuxI-type AHL synthases catalyze the formation of the AHL from the substrates S-adenosyl-L-methionine (SAM) and acyl-acyl carrier protein (acyl-ACP). Enzymatic synthesis of AHLs using purified substrates for TraI (from Agrobacterium tumefaciens) verified that both SAM and acyl-ACP are substrates for AHL synthesis in vitro. X-ray crystallographic structural analyses of two LuxI-type AHL synthases form the basis of the current molecular understanding of AHL synthesis. The structure of the EsaI enzyme from Pantoea stewartii was determined from the native sequence. The structure of the LasI enzyme from Pseudomonas aeruginosa was determined from an active form that had been engineered to improve solubility and crystallization properties. The LasI structure provided a less clear explanation for the selectivity of AHL synthases for acyl-ACPs with long acyl chains. The LasI acyl-chain binding pocket is actually an elongated tunnel through the enzyme that is formed by hydrophobic residues at similar positions in the enzyme as those in the EsaI pocket. The residues in EsaI that occlude the pocket are larger than those in the same position in LasI, which limits the acyl chain size to a C6 acyl-chain.
Oscillator phase noise reduction using optical feedback with dual drive Mach-Zehnder modulator

A reduced phase noise of stable microwave oscillators is reported by forced oscillation using self-ILPLL technique fiber optical delayed feedback. Fiber optic links using single drive and dual drive MZM have been used to implement the optical feedback path. A phase noise reduction of 22 dB at 300 Hz offset is measured for a commercially available DRO at 10 GHz using dual drive MZM in long fiber optic delay lines. The measured −127 dBc/Hz at 14 kHz offset has been demonstrated by employing 4km and 8km fiber optic delay lines.
The effect of substrate growth temperature on the optical properties of self-assembled InAs quantum dots

Summary form only given. We investigate MBE-grown samples of capped InAs quantum dots with substrate growth temperatures ranging from 465/spl deg/C to 515/spl deg/C and explore their optical properties. In our first measurement, we perform low temperature (5K) photoluminescence experiments on ensembles of quantum dots in our samples using 100 /spl mu/w of continuous-wave, 735 nm light from a Ti-sapphire laser for exciting the quantum dots. We find that the photoluminescence emission energy decreases with increasing substrate growth temperature. Our second type of optical experiment involves the time resolution of the optical emission from a pulsed laser source. We retrieve time-resolved data using a Hamamatsu streak-camera with attached monochrometer. Our streakcamera measurements yield color-hue plots of intensity versus wavelength versus time. This allows us to tell not only where in the energy spectrum our quantum dots are emitting, but also for how long they emit. We find that increasing the growth temperature decreases the quantum dot lifetime.
Regulation of IL-17 in autoimmune diseases by transcriptional factors and microRNAs

In recent years, IL-17A (IL-17), a pro-inflammatory cytokine, has received intense attention of researchers and clinicians alike with documented effects in inflammation and autoimmune diseases. IL-17 mobilizes, recruits and activates different cells to increase inflammation. Although protective in infections, overproduction of IL-17 promotes inflammation in autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, psoriasis, among others. Regulating IL-17 levels or action by using IL-17-blocking antibodies or IL-17R antagonist has shown to attenuate experimental autoimmune diseases. It is now known that in addition to IL-17-specific transcription factor, RORγt, several other transcription factors and select microRNAs (miRNA) regulate IL-17. Given that miRNAs are dysregulated in autoimmune diseases, a better understanding of transcriptional factors and miRNA regulation of IL-17 expression and function will be essential for devising potential new therapies. In this review, we will overview IL-17 induction and function in relation to autoimmune diseases. In addition, current findings on transcriptional regulation of IL-17 induction and plausible interplay between IL-17 and miRNA in autoimmune diseases are highlighted.
Exercise-induced neuroplasticity in human Parkinson's disease: What is the evidence telling us?

Abstract Introduction While animal models of exercise and PD have pushed the field forward, few studies have addressed exercise-induced neuroplasticity in human PD. Method As a first step toward promoting greater international collaboration on exercise-induced neuroplasticity in human PD, we present data on 8 human PD studies (published between 2008 and 2015) with 144 adults with PD of varying disease severity (Hoehn and Yahr stage 1 to stage 3), using various experimental (e.g., randomized controlled trial) and quasi-experimental designs on the effects of cognitive and physical activity on brain structure or function in PD. We focus on plasticity mechanisms of intervention-induced increases in maximal corticomotor excitability, exercise-induced changes in voxel-based gray matter volume changes and increases in exercise-induced serum levels of brain derived neurotrophic factor (BDNF). Finally, we provide a future perspective for promoting international, collaborative research on exercise-induced neuroplasticity in human PD. Conclusion An emerging body of evidence suggests exercise triggers several plasticity related events in the human PD brain including corticomotor excitation, increases and decreases in gray matter volume and changes in BDNF levels.
Composite control of direct-drive robots

The present trend toward the development of gearless robots aims to eliminate mechanical complexity where possible. Consistent with this objective is the increasing use of brushless motors as joint actuators. These electronically commutated motors do have the required characteristic of high torque at low-speed, but pose a challenge for accurate torque control at the joints. It is shown that by coordinating the feedback linearization design of the mechanical link dynamics with that of the electrical motor dynamics, greater control accuracy can be achieved. The feedback linearization is applied to a reduced-order model which accounts for the electrical dynamics with an asymptotic approximation of the integral manifold. A first-order correction to the current commands of joint actuators improves the torque tracking accuracy of the robot. >
Perioperative opiate requirements in children with previous opiate infusion.

Summary Background: Critically ill children often require continuous opiate infusions. Tolerance may develop requiring a weaning strategy to prevent withdrawal symptoms. These children may also require subsequent surgical procedures. This is the first study to investigate whether previously opiate-tolerant patients require higher doses of opiates for adequate pain management perioperatively. Methods: A retrospective study was conducted at a tertiary children’s hospital to investigate whether children previously exposed to continuous opiates for 10 or more days with subsequent weaning from those opiates will have similar or increased perioperative opiate requirements when compared to opioid-naive controls. Study patients included 31 children with previous continuous opiate exposure for 10 or more days followed by weaning and without signs of withdrawal for at least 72 h prior to the surgical procedure. Excluded were patients over 18 years of age, those whose surgical procedures would be unlikely to require perioperative opiates, oncological patients, burn patients, neurologically devastated patients, and patients who received regional anesthesia in addition to perioperative narcotics. The control group consisted of 31 age- and case-matched opiate-naive patients who underwent a surgical procedure during a similar time frame as the study patient. The medication administration record was reviewed for the length of continuous opiate exposure, date of last opiate use prior to a subsequent surgical procedure, and opiate use during the perioperative period. Opiate use was calculated as morphine equivalents per kilogram body weight (MSEQ·kg−1). The Wilcoxon rank sum test was used for univariate comparisons between matched pairs, and P-values <0.05 were considered statistically significant. Results: The perioperative opiate requirements in opiate-exposed patients (median, interquartile range: 0.14, 0.08–0.25 MSEQ·kg−1) were not significantly different from opiate-naive patients (median, interquartile range 0.10, 0.05–0.2 MSEQ·kg−1, P = 0.19). Pain scores indicated that patients were generally comfortable in the perioperative period. Conclusions: The perioperative opiate requirements of pediatric patients who were successfully weaned after prolonged opiate use were similar to opiate-naive patients. A history of prolonged opiate use alone does not necessitate special pain management for future procedures.
Serotonin-induced protein phosphorylation in a lobster neuromuscular preparation

Three substances believed to be neurohormones in the lobster-- serotonin, octopamine, and proctolin--can modulate the physiology of the dactyl opener muscle of the lobster walking leg. All three act directly on muscle fibers to cause long-lasting contractures. In addition, serotonin enhances the release of transmitter from the excitatory and inhibitory axons that innervate the muscle. We now report that serotonin, applied to intact nerve-muscle preparations, increases the phosphorylation of a soluble 29,000-dalton protein by as much as 20-fold. In two respects the phosphorylation parallels the physiological effects of serotonin: both have a slow time course, and both are caused by low concentrations of serotonin (thresholds of approximately 10(-8) M). The 29,000-dalton protein is present in many lobster tissues, including thoracic ganglia, gills, and several different muscles. This suggests that the phosphorylation participates in some aspect of metabolism common to many types of cells, rather than in an activity unique to nerve or muscle. The function of the phosphorylated protein remains unknown. Several lines of evidence suggest that the phosphorylation is mediated by a cyclic nucleotide, probably cyclic AMP. (1) Adding cyclic AMP or cyclic GMP to nerve- muscle homogenates leads to the phosphorylation. (2) Adding 8-Br-cyclic AMP or 8-Br-cyclic GMP to intact preparations leads to the phosphorylation. (3) In intact tissue, forskolin, an adenylate cyclase activator, and isobutylmethylxanthine, a phosphodiesterase inhibitor, increase cyclic AMP and cyclic GMP and also cause the phosphorylation. (4) Serotonin increases cyclic AMP in intact preparations. (5) RMI 12,330A, which blocks the serotonin-induced cyclic AMP increase, also blocks the phosphorylation. (6) Serotonin has no detectable effect on cyclic GMP. This suggests that cyclic AMP, and not cyclic GMP, is the second messenger that mediates phosphorylation in vivo. In contrast, calcium is not likely to mediate the phosphorylation. Agents that block calcium channels do not block the serotonin-induced phosphorylation, and agents that increase sarcoplasmic calcium do not cause it. Furthermore, calcium does not induce the phosphorylation in a homogenate. One of the other modulators, proctolin, does not increase cyclic AMP or cause the phosphorylation even at concentrations 10(6)- fold greater than the hormone9s threshold for producing contractures. The third modulator, octopamine, causes small increases in cyclic AMP and is a weak agonist of the phosphorylation. Neither proctolin nor octopamine alters cyclic GMP levels.
Salmonellosis in infants and children.

Bacteriologic investigation of 121 household contacts of 28 infants and children with salmonella gastroenteritis revealed that 42 (34.7 per cent) had stool cultures positive for salmonella. Of those with positive cultures, 23 had an illness consistent with salmonellosis and 19 were asymptomatic carriers. Long-term bacteriologic follow-up revealed that the duration of salmonella carriage was shortest in those patients who had not initially received antibiotic therapy. Only one convalescent carrier had an illness consistent with recurrent salmonellosis. It is concluded that antibiotic therapy is not indicated in the treatment of uncomplicated salmonella gastroenteritis or of asymptomatic and postsymptomatic carriers.
A comparative analysis of reactions from multicultural and culturally homogeneous teams to decision making with and without GDSS technology

Cultural Diversity in the U.S. workforce is increasing, in addition, organizations are requiring greater worker involvement and teamwork. While cultural diversity provides unique opportunities to stimulate the work environment, it can also create problems in individual interaction that often hinders group performance. Therefore, it is imperative to determine how multicultural team performance is similar and different from culturally homogeneous team performance. In the Information Age a number of organizations are using technology such as Group Decision Support Systems (GDSS) to promote participation and improve team interaction. This article provides the results of a pilot study where survey responses were collected from two categories of teams, multicultural teams and culturally homogeneous teams. Participants were surveyed on their preferences for team decision making, in reaction to team exercises, within a GDSS environment and within a traditional, non-GDSS environment. An analysis of the responses showed that a significantly higher percent of multicultural team members, in comparison to culturally homogeneous team members, responded more favorably for using a GDSS in certain aspects of team decision making. For example, multicultural team members to a greater extent preferred the computer environment for "discussion of issues" and "expressing ideas." Implications for using GDSS technology for team building within multicultural organizations are discussed.
Development of somatostatin-containing neurons and fibers in the rat hippocampus

Abstract Using a combination of in situ hybridization and immunohistochemistry, the development of somatostatin (SS)-containing neurons and fibers was examined in the rat dorsal hippocampus and dentate gyrus. The major development of this hippocampal peptidergic system occurs postnatally. At postnatal day 1 (P1), neurons containing SS mRNA are evident primarily in the stratum oriens, but also in the hilus of the dentate gyrus. Similar neurons are also immunoreactive for SS28 and SS28(1–12), suggesting a minimal lag in the transcription of SS mRNA and its translation into specific SS peptides. The number of SS neurons increases postnatally to P10, followed by a decrease in number in the adult. This transient change in the number of SS neurons coincides with dramatic changes in SS28(1–12)-immunoreactive fibers, which are initially present in the stratum lacunosum moleculare, with no significant immunoreactivity in the dentate gyrus. By P15, the molecular layer of the dentate gyrus is densely innervated, while similar immunoreactivity in the stratum lacunosum moleculare is greatly reduced. These data are consistent with a transient projection from the stratum oriens to the stratum lacunosum moleculare, which is replaced by a projection from the hilus to the molecular layer of the dentate gyrus as this structure matures.
Treatment of cutaneous complications of AIDS

Persons who are infected by human immunodeficiency virus (HIV) can present with the full array of cutaneous diseases seen in unaffected individuals. In this report, we review the treatments for skin lesions that are most commonly associated with HIV infection, limiting the discussion to those modalities used primarily by the dermatologist.
Comprehensive Urban High School: Are there Better Options for Poor and Minority Children?

This article examines four models for secondary education (magnet schools, school reform models, small high schools, and Catholic high schools) and their impact on student achievement in the urban ...
Preclinical toxicology studies with tobramycin

Abstract Tobramycin, an aminoglycoside antibiotic, has been administered to mice, rats, cats and dogs for toxicologic evaluation. The sc LD50 values in mice and rats were 441 and 969 mg/kg, respectively. Deaths were preceded by CNS depression and occurred within 1 hr of treatment. A 100 mg/kg iv dose in chloralose-anesthetized cats produced a moderate, transient decrease in blood pressure and a significant decrease in inspiratory volume and soleus twitch force. Rats were given daily sc doses of 15–120 mg/kg for 3 months. Renal tissue change, the only drug effect evident histologically, ranged in degree from a slight reparative nephrosis at the lowest dose to cortical tubular necrosis in some rats that received the highest dose. In a 1-month study, a daily im dose of 7.5 mg/kg had no apparent effect on dogs, but a 30 mg/kg dose produced severe renal damage. Vestibular injury occurred within less than 30 days in all cats that received daily sc doses of 50 mg/kg, but no vestibular changes were observed in cats that were given 65 doses of 25 mg/kg. The toxicologic effects observed in tobramycin-treated animals were qualitatively and quantitatively similar to those observed with gentamicin.
Characterization of concentrated colloidal suspensions using time-dependent photon migration measurements

Abstract A method is presented to characterize concentrated suspensions of particles using frequency-domain photon migration in order to demonstrate its potential for on-line monitoring in the pharmaceutical and chemical based industries. In this study, the isotropic scattering coefficient was determined from FDPM measurements conducted at wavelengths between 448 and 835 nm using surfactant stabilized polystyrene latices of 195–335 nm mean diameter, 7–19% polydispersity and concentrations between 1 and 40% by volume. Upon using the Percus–Yevick model for static structure of monodisperse spheres to account for hindered scattering in the inverse solution, determination of the volume fraction and mean particle diameter were considerably improved size at solids volume fractions of 10% or greater. Owing to (i) the relative refractive index of polystyrene in water, (ii) the inaccuracy of the first order particle interaction model for suspensions with polydispersity >8%, and (iii) the minimal number of wavelengths used, it was difficult to recover the variance of the unimodal particle size distributions. Nonetheless, this work demonstrates the use of time-dependent measurements of multiply scattered light to characterize suspensions with solids volume fractions greater than 10%.
Native defects in gallium nitride

The results of an extensive theoretical study of native defects in hexagonal GaN are presented. We have considered cation and anion vacancies, antisites, and interstitials. The computations were carried out using ab initio molecular dynamics in supercells containing 72 atoms. N vacancy introduces a shallow donor level, and may be responsible for the n-type character of as-grown GaN. Due to the wide gap of nitrides, self-compensation effects strongly reduce both n-type and p-type doping efficiencies due to the formation of gallium vacancy and interstitial Ga, respectively.
Half tetrad analysis in angiosperms.

Abstract A biochemical technique involving analysis of endosperm is proposed for detecting meiotic crossovers and for gene mapping in angiosperms with bisporic embryo sacs. In bisporic embryo sac development two spores resulting from meiosis-II division of the same meiosis-I daughter cell contribute two thirds of the total genetic information to the triploid endosperm nucleus, the other third coming from a sperm in the fertilizing pollen grain. In controlled crosses where the marker gene codes for allozymes with phenotypes sensitive to gene dosage, the maternal meiotic contribution to the endosperm nucleus may be determined, thereby allowing crossovers between the marker locus and the centromere to be detected.
Engaging Underrepresented High School Students in an Urban Environmental and Geoscience Place-Based Curriculum

ABSTRACT High school students in a large urban area, undergraduate students, and geoscience faculty at a local college used a place-based pedagogical approach to engage in real geoscience problem-based inquiry in a local urban park. The overarching goals of this project were to learn the potential of place-based geoscience research experiences to: influence students' science identities and increase participation of urban youth in science. Student researchers participating in the activity (N = 22) completed Likert-scale pre- and post-surveys, which were analyzed using paired t-tests. Student journal reflections were analyzed. Survey and journal reflection results showed that students' science identities were enhanced and student interest in learning science outdoors increased through participation in the program. The evaluation of the project outcomes add to the body of knowledge describing how outdoor settings and place-based pedagogies can be used to increase urban students' interest in science, and demo...
Affinity of CUP2, a copper-dependent transcription factor, for DNA sequences upstream of the yeast metallothionein gene

Abstract CUP2, the protein that regulates the expression of the copper metallothionein gene of the yeast Saccharomyces cerevisiae, itself contains a copper cluster that is essential for activity. One of the binding sites for CUP2 upstream of the metallothionein gene, called the UASc, contains an imperfect inverted DNA sequence repeat. We have measured the binding affinity of CUP2 to the two half-sites of the UASc in five different DNA molecules, each containing one or two half-sites. The values of the dissociation constants we found were as follows: one upstream half-site, 1.25 nM; two upstream half-sites, 1.57 nM; one downstream half-site, 10.19 nM; two downstream half-sites, 10.37 nM; the wild type UASc site, 1.68 nM and 10.37 nM. We found no evidence for cooperativity in the interaction of CUP2 with any of the DNA molecules containing two half-sites.