cssi/SciSciGPT-SciSciNet huggingface dataset:
Mutation Analysis and Regulation of PpsR

In the presence of oxygen, Rhodobacter sphaeroides derives energy from aerobic respiration. When oxygen tension decreases below certain threshold levels, it develops in-tracytoplasmic membrane vesicles which house the photosystem (PS) comprised of the reaction center and light harvesting (LH) complexes. When light becomes available under anaerobic conditions, the bacterium uses PS for capturing photons and ultimately converting light energy into biochemical energy. In the absence of light, the PS is produced gratuitously. This suggests that oxygen is a major environmental factor affecting PS development in R. sphaeroides. Under anaerobic conditions, light intensity affects the cellular abundance and proportion of photocomplexes [1].
Saharan Dust Transport Over the North Atlantic Ocean and Mediterranean: An Overview

North Africa serves as a huge reservoir of mineral dust. Dust sources are active all year, especially during the summer when they feed strong pulses of dust across the Mediterranean to Europe and the Middle East and across the Atlantic to the Caribbean, Central and North America. Over the North Atlantic in the low and mid latitudes, mineral dust is the major non-sea-salt aerosol component, exceeding the combined mass of all other species. Model estimates yield a dust deposition of 170 Tg yr−1 to the Atlantic, 25 Tg yr−1 to the Mediterranean, and 5 Tg yr−1 to the Caribbean. There is an extremely large seasonal variability in dust deposition and we might expect a comparable variability in consequent ocean effects. However, deposition estimates are highly uncertain because of the paucity of deposition data throughout the region. The greatest uncertainty is associated with the estimation of dry deposition fluxes which in ocean regions close to sources could constitute by far the largest fraction of the total flux. In recent time, dust mobilization may have increased markedly due to human activities; thus a substantial fraction may be regarded as an anthropogenic product.
New Developments in High Temperature and High Strength Polyquinolines

The relationships between the structures and the morphology, solution properties and mechanical properties of polyquinolines depend upon the manner in which the quinoline units are linked together.A wide variety of structures account for polyquinolines that either are amorphous, soluble in common organic solvents and have moderately high glass transition temperatures (~250°C) or are crystalline, are soluble only in acidic solvents, forming anisotropic solutions, and have high crystalline transition temperatures (>500°C). The conducting properties of certain doped polyquinolines containing either total conjugation or sulfur linkages between quinoline units are described. Polyquinolines containing biphenylene units either in the main chain or at the chain ends undergo crosslinking and chain extension reactions. The use of biphenylene end-capped oligomeric polyquinolines as matrix resins in graphite composites is discussed.
Do People Ask Good Questions

People ask questions in order to efficiently learn about the world. But do people ask good questions? In this work, we designed an intuitive, game-based task that allowed people to ask natural language questions to resolve their uncertainty. Question quality was measured through Bayesian ideal observer models that considered large spaces of possible game states. During free-form question generation, participants asked a creative variety of useful and goal-directed questions, yet they rarely asked the best questions as identified by the Bayesian ideal observers (Experiment 1). In subsequent experiments, participants strongly preferred the best questions when evaluating questions that they did not generate themselves (Experiments 2 and 3). On one hand, our results show that people can accurately evaluate question quality, even when the set of questions is diverse and an ideal observer analysis has large computational requirements. On the other hand, people have a limited ability to synthesize maximally informative questions from scratch, suggesting a bottleneck in the question asking process.
A numerical simulation of pulsed reacting jets

Numerical simulations of unsteady combusting jets are performed using a dual-time, fully coupled, implicit procedure that enables time step sizes to be based on the particle velocity. Results are presented for a range of I'roude numbers that span the momentum dominated to buoyancy-dominated regimes. At high Froude number conditions, heat release is shown to be stabilizing while at low Froude numbers it is destabilizing to the point that the flames become spontaneously unstable. Dimensional evaluation of the buoyancy induced unsteady effects agrees well with the 10–15 11z. flickering observed in laminar flame experiments.
Focusing on the User

Throughout my years as a front-end developer, my thoughts while building out websites and applications for the web revolved around delivering a consistent and functional interface. More specifically, it was about how I would create that consistency in one of, if not, the most inhospitable environments in the digital world: the web browser.
Success of direct-acting, antiviral-based therapy for chronic hepatitis C is not affected by type 2 diabetes

Chronic hepatitis C virus (HCV) is a risk factor for type 2 diabetes. In the era of interferon-based HCV therapy, type 2 diabetes was associated with decreased likelihood of sustained virologic response (SVR). Preliminary studies suggest that type 2 diabetes may not reduce the efficacy of regimens involving direct-acting antiviral (DAA) medications. We aimed to determine whether preexisting type 2 diabetes is associated with a reduced rate of SVR achieved 12 weeks after treatment of HCV with DAA-based regimens.
Zika virus infection and temperature significantly impact Aedes albopictus gut microbiota

BackgroundVector-borne pathogens must survive and replicate in the hostile environment in the insect gut before successful transmission. The insect gut bacteria can have a modulatory effect on their vectorial capacity. The relationship between infection, temperature and the mosquito gut microbiome are not well characterized.nnMethodology/ Principal findingsThis study aimed to delineate the effect of Zika virus (ZIKV) infection and temperature variation on the microbial profile of Aedes albopictus mosquitoes. Ae. albopictus were reared at diurnal temperature of day 28{degrees}C/ night 24{degrees}C and day 30{degrees}C/ night 26{degrees}C. Mosquitoes were given infectious blood meals with 8.3 log10 PFU/ml ZIKV and 16S rRNA sequencing was performed on guts at 7 days post-infectious bloodmeal exposure.nnBlood meal acquisition and ZIKV exposure significantly reduced the gut taxa diversity while increase in temperature significantly altered the bacterial composition. A number of individual bacterial genera, most notably Elizabethkingia and Neoasaia, were found to be associated with blood meal digestion, ZIKV exposure and susceptibility to infection. To the best of our knowledge, we identified Neoasaia for the first time in the midgut of an arthropod vector.nnThe findings of this study demonstrate that both temperature and ZIKV infection modulate the midgut microbial profile of Ae. albopictus mosquitoes. This may impact arbovirus transmission dynamics in future climate change scenarios and inform novel control strategies.
Mechanical Circulatory Support Driveline Infection Reduction through Nursing Quality Improvement

Introduction Infection in patients with left ventricular assist device is a leading cause of morbidity and mortality resulting in increased risk for additional complications such as bleeding, thrombosis and stroke. The purpose of this quality improvement project was to reduce driveline infections through implementation of an evidence-based bundled dressing kit and education to nursing staff. Hypothesis Education of nurses and implementation of a standardized kit for driveline dressing changes will reduce driveline infection rates and improve nurse knowledge, satisfaction and confidence with infection prevention practices. Methods A multifocal intervention to improve standardization of care related to LVAD driveline care practices was initiated in 2018 on 5 nursing units. A multidisciplinary group contributed to creation of a driveline dressing kit. Nursing unit champions were identified and educated regarding driveline care knowledge and dressing change techniques. The institutional policy was updated to reflect new practices. In-person teaching and online educational videos were used to deliver education to nursing staff from the 5 units. A knowledge survey was used to test nursing knowledge immediately following the initial education and was repeated after 6 months to assess knowledge retention. Nurses were additionally asked to respond to questions regarding satisfaction and confidence with practice changes at the 6-month follow-up. Results An overall reduction in driveline infection rate from 35.7% in the 8 months prior to implementation of the DL dressing kit to 12.5% in the 8 months post implementation. Of the champion group, 26 nurses received 100% on their knowledge assessment. After in-servicing, 50% of floor nurses scored higher than 90% on their knowledge assessment. After 6 months, 57% of floor nurses scored greater than 90%. Of respondents, 93.6% agreed or strongly agreed that they “feel confident to expertly provide driveline dressing changes to LVAD patients using the new kit,” and 89.4% agreed or strongly agreed that they “feel confident that I can teach patients and their caregivers on how to use the new driveline dressing kit.” Conclusions While we have seen a great improvement in the rate of DLI, there are continued needs to reinforce nursing knowledge and skills related to driveline care and dressing change practices. Ongoing monitoring of driveline infection rates and further efforts to establish best practices are needed.
Associations of Early Medicaid Expansion With Insurance Status and Stage at Diagnosis Among Cancer Patients Receiving Radiation Therapy

Abstract Purpose Medicaid expansion in 2014 is associated with improved insurance coverage and stage at diagnosis in cancer patients. However, little is known about the effect of early Medicaid expansions in 2010 to 2011 on outcomes in radiation therapy recipients. The objective of this study was to estimate the effect of early Medicaid expansion on insurance status and stage at diagnosis among radiation therapy recipients. Methods and Materials The Surveillance, Epidemiology, and End Results database was queried for cases aged 18 to 64 diagnosed in 2007 to 2013 with a first primary malignancy treated with radiation therapy. Difference-in-differences analyses were used to compare changes in insurance coverage and stage at diagnosis from 2007 to 2009 and 2011 to 2013 in expansion relative to nonexpansion states. Results There was a –0.48 (95% confidence interval [CI], –0.84 to –0.13; P = .007) percentage point (PP) reduction in uninsured in expansion relative to nonexpansion states, primarily among counties with lower educational attainment (–1.73 PP; 95% CI, –2.72 to –0.75). Increases in early stage diagnoses in expansion relative to nonexpansion states were found overall and in breast (1.56 PP; 95% CI, 0.45-2.68; P = .006), colorectal (3.72 PP; 95% CI, 0.33-7.12; P = .032), and lung (1.49 PP; 95% CI, 0.25-2.72; P = .018) cancers. Decreases in late stage diagnoses were found in cervical (–5.91 PP; 95% CI, –9.58 to –2.25; P = .002), colorectal (–2.72 PP; 95% CI, –5.43 to –0.01; P = .05), and lung (–3.28 PP; 95% CI, –5.47 to –1.1; P = .003) cancers. Conclusions For radiation therapy recipients, early Medicaid expansion was associated with decreased percent uninsured, particularly among low education counties, and earlier stage diagnoses for screenable cancers. Thus, early Medicaid expansion may improve access to care and decrease disparities for radiation therapy recipients.
Role of hydrodynamic interactions in chemotaxis of bacterial populations

How bacteria sense local chemical gradients and decide to move has been a fascinating area of recent study. Chemotaxis of bacterial populations has been traditionally modeled using either individual-based models describing the motion of a single bacterium as a velocity jump process, or macroscopic PDE models that describe the evolution of the bacterial density. In these models, the hydrodynamic interaction between the bacteria is usually ignored. However, hydrodynamic interaction has been shown to induce collective bacterial motion and self-organization resulting in larger mesoscale structures. In this paper, the role of hydrodynamic interactions in bacterial chemotaxis is investigated by extending a hybrid computational model that incorporates hydrodynamic interactions and adding components from a classical velocity jump model. It is shown that by including hydrodynamic interactions, a suspension with a low initial volume fraction can exhibit locally high concentrations in bacterial aggregates. Also, it is shown that hydrodynamic interactions enhance the merging of the small aggregates into larger ones and lead to qualitatively different aggregate behavior than possible with pure chemotaxis models. Namely, differences in the shape, number, and dynamics of these emergent clusters.
Toxicity of acute exploratory amphetamine-salt medication in amphetamine-naïve pediatrics: a retrospective cohort study.

Background and Objectives: Pediatric ingestions of amphetamines used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD) are on the rise. Little data provide an amphetamine dose at ...
The impact of risk factors on gastroparesis at an urban medical center.

Background Gastroparesis is a complex and poorly understood disease. The literature is lacking with respect to the epidemiology of patient comorbidities and their effect on gastric emptying. We aimed to describe the most common comorbid conditions among patients with gastroparesis in an urban population and quantify the effect of these comorbidities on the severity of delayed gastric emptying (DGE). Methods We examined the medical records of all patients diagnosed with gastroparesis at a quaternary care center between 2014 and 2015. The severity of DGE was analyzed after patients were stratified for possible causative etiologies. Likelihood ratio tests were used to assess the significance of demographic and scintigraphic variation in this population. Results Of the 221 patients, 56.1% were Caucasian and 31.7% were African American. Among these patients, 29.4% had evidence of medication-associated gastroparesis, 29.0% had diabetes-associated gastroparesis, and 31.7% had idiopathic disease. African American patients with gastroparesis were more likely to have diabetic gastroparesis than patients of other races (P=0.01). There was a statistically significant relationship between the number of major risk factors and the severity of a patient's DGE (P=0.004). Conclusions Among a diverse urban population, patients with DGE often carry multiple comorbid conditions that serve as risk factors for the development of gastroparesis, including prescriptions for narcotic medications. Greater numbers of these comorbid conditions are associated with more severe disease. Demographics are significantly associated with the etiology and severity of gastroparesis; in particular, African American patients are more likely to have diabetic gastroparesis than patients of other races.
ANTIGEN PRESENTATION IN THE T-LYMPHOCYTE PROLIFERATION ASSAY: REQUIREMENT FOR GENETIC IDENTITY AT THE MAJOR HISTOCOMPATIBILITY COMPLEX

In this paper we describe a method for stimulating T-lymphocyte proliferation using antigen bound to spleen cells. With this form of antigen presentation, syngeneic spleen cells were found to present antigen better to peritoneal exudate T-lymphocyte-enriched cells (PETLES) than semisyngeneic spleen cells, which in turn could present antigen better than allogeneic spleen cells. Spleen cell mixing experiments demonstrated that these genetic restrictions were not the result of nonspecific suppression by the ongoing mixed lymphocyte reactions (MLR). Furthermore, incompatibility at the Mls locus generated a strong MLR but failed to prevent antigen presentation if the spleen cells and PETLES were H-2 compatible. Through the use of H-2 congenic-resistant lines and their recombinant strains, it was possible to map at least one gene controlling the successful presentation of the antigen, DNP 6 -ovalbumin, to the I-A subregion of the major histocompatibility complex (MHC) .
Does marijuana use among African American adolescent males differ based on school factors

Marijuana use among adolescents is a major public health problem. The purpose of this study was to examine whether past-year marijuana use among African American adolescent males differed based on ...
Bilateral defence and security cooperation despite disintegration: Does the Brexit process divide the United Kingdom and Germany on Russia?

With wavering US support and Brexit unfolding, cooperation between Germany, the EU's economic powerhouse, and the United Kingdom, Western Europe's prime military power, becomes crucial for Europe's overall ability to deal with a resurgent Russia. Does institutional and normative disintegration between states, such as the Brexit process, weaken bilateral security cooperation? This article argues that such cooperation persists if both states continue to jointly perceive a third actor as threatening while regarding each other as useful and reliable when it comes to ameliorating this shared threat. The argument is tested on a case of intrinsic theoretical, historical, and political importance: British-German cooperation towards Russia before and after the 2016 Brexit referendum. The article finds, against a wide pessimist consensus to the contrary, that cooperation strengthened during the Brexit process. As the Ukraine crisis had caused converging threat perceptions since 2014, Brexit incentivised both sides to signal ongoing reliability to each other and, consequently, to view each other as more capable allies. The article combines qualitative comparisons and congruence analysis, drawing data from British, German and Russian primary sources in their respective original languages, including foreign and security policy documents as well as interviews with stakeholders involved in policy formation.
Reflections on Year One of "Personalized Nutrition".

It has been one year since the Journal of the American College of Nutrition (JACN) became the flagship journal of the American Nutrition Association, with a particular emphasis in disseminating sci...
Circulating Cancer Biomarkers.

Cancer is among the major public health problems worldwide, representing the leading cause of morbidity and mortality in industrialized countries [...]
Delegated Censorship: The Dynamic, Layered, and Multistage Information Control Regime in China:

How does internet censorship work in China, and how does it reflect the Chinese state’s logic of governing society? An online political publication, Global China (海外看世界), was created by the authors...
Herd mastitis investigation report

A case study of an investigation into a herd mastitis problem is described where possible causes are identified and preventative techniques are recommended.
Hurricane Effect on Sea Level at Charleston

Tropical cyclones from 1922 to 1955 have been classified according to orientation of their tracks with respect to Charleston Harbor; theoretically, displacement of sea level depends on this orientation; tabulated displacements caused by tropical cyclones during 34 yr of tide observations bear out relationships.
Personalized management of hepatocellular carcinoma based on molecular information: Future prospects

Hepatocellular carcinoma (HCC) is a growing clinical problem, as the second leading cause of cancer deaths worldwide (GLOBOCAN, http://globocan.iarc.fr) and one of the only increasing causes of cancer-related mortality in the United States.[1] The landscape of clinical demographics has been changing with the epidemic of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH), for which HCC risk factors are being actively explored. The recent emergence of highly effective direct-acting antivirals (DAA) for hepatitis C virus (HCV) has shifted the focus of research interest to outcomes after viral eradication. Ever-expanding inventories of molecular targeted agents and genomics technologies have enabled exploration of more personalized/stratified management of the patients. Here, we provide an overview of evolving challenges in HCC in relation to the changing landscape.
Cystathionine γ-Synthase THE NATURE OF INTRAMOLECULAR PROTON SHIFTS IN THE γ ELIMINATION REACTION

One of the reactions catalyzed by cystathionine γ-synthase, a bacterial pyridoxal phosphate enzyme, is the decomposition of O-succinylhomoserine, by γ elimination, to yield ammonia, succinate, and α-ketobutyrate. It had been shown that when this reaction was carried out in 2H2O 1 atom of deuterium was stereospecifically introduced (the absolute configuration is confirmed in this paper) at carbon 3 of α-ketobutyrate, but considerably less than 1 atom of deuterium was present in the newly formed terminal methyl group. The latter result indicated that a portion of the hydrogen introduced at carbon 4 originated in the substrate, presumably by intramolecular proton transfer from either the α or the β position of the homoserine moiety. To answer this question we have synthesized homoserine with deuterium in the α, the β, or in both positions, have succinylated the various preparations, and allowed them to be decomposed in H2O or 2H2O by cystathionine synthase. The distribution of hydrogen (1H) and deuterium in the resultant α-ketobutyrate has been determined by NMR and mass spectroscopy. The results showed that: (a) there was proton (1H) transfer from both α and β positions of substrate to γ position of product; (b) the β hydrogen transferred was the same as the one shown in the preceding paper to be rapidly exchanged; (c) there was not a measurable amount of deuterium transfer from either α or β position. The effects of α and β deuterium substitution on the kinetic constants for the γ elimination reaction were found to be rather small. The explanation postulated for these results involves a single polyhydric basic group of the enzyme functioning in the abstraction of both the α and β hydrogens of the substrate and in a series of intramolecular proton transfers leading to their partial retention in the methyl group of α-ketobutyrate.
NMR spectral studies—XII : Trichloroacetyl isocyanate as an in situ derivatizing reagent for 13C NMR spectroscopy of alcohols, phenols and amines

Abstract Trichloroacetyl isocyanate (TAI) has been found to be a useful in situ derivatizing reagent for the 13 C NMR studies on alcohols, phenols and amines. The carbinol carbon of aliphatic alcohols shows downfield shifts the size of which permits distinction between primary, secondary and tertiary saturated alcohols. In allylic and propargylic alcohols the γ-carbon undergoes large downfield shifts while the β-carbon is shifted upfield. In the case of phenols, the OH-bearing carbon is shifted upfield, the o - and p -carbons are shifted downfield but m -carbons are virtually unaffected. Addition of TAI to amines and anilines produces various size shifts for the α- and β-carbons. The use of TAI is thus a valuable aid in the assignment of the resonance signal of a carbon carrying an OH or NH-group as well as some neighboring carbons in 13 C NMR spectra for structural and biosynthetic studies.
Understanding mathematical literacy: The contribution of research

Amid the current ‘math wars’ in the United States, research evidence is being both demanded and attacked by all sides. A recent study designed to synthesize the literature on mathematics learning and to provide research-based recommendations, advice, and guidance developed an elaborated view of mathematical literacy, termed mathematical proficiency in the study report. Mathematical proficiency can serve as a focus for both research and practice, avoiding the extreme positions with respect to the goals of mathematics learning that are so often found in disputes over school mathematics. The study also demonstrated how research could be synthesized so that evidence from research might be used more productively for changing school mathematics in ways that would yield greater mathematical literacy for all.
Atomic interactions in protein-carbohydrate complexes: Tryptophan residues in the periplasmic maltodextrin receptor for active transport and chemotaxis

Abstract We have refined the 1.9 A resolution crystal structures of two maltodextrin receptor mutants in which tryptophan residues 230 and 232 have been changed to alanine and compared these structures with the refined 1.7 A structure of the wild-type protein. In the wild-type structure, Trp230, which is located in the maltodextrin-binding groove, stacks against the B-face of the reducing sugar of the bound maltose. Trp232, which is located near the protein surface, does not participate directly in sugar binding. Relative to the wild-type structure, neither mutation caused a significant rearrangement in the overall protein structure or in the mode of binding maltose. Although the position once occupied by Trp230 remains empty, a new water molecule has moved near the void. In contrast, a new water molecule has entered into the space once occupied by Trp232. Whereas one hydrogen bond is formed with the water molecule near the Trp230 void, no hydrogen bond is associated with the water molecule occupying the space vacated by Trp232. The three van der Waals' contacts between Trp230 and maltose in the wild-type structure that are lost in the W230A mutation could contribute to the 12-fold decrease in ligand-binding activity of the mutant protein. The W232A mutation causes little change in binding activity. The structures of these mutant proteins also provide some insight into the complicated tryptophan fluorescence spectra of the maltodextrin binding-protein. The change in fluorescence due to the deletion of Trp230 can readily be explained as resulting directly from loss of Trp230 in the sugar-binding site. The change in fluorescence due to deletion of Trp232, however, is ascribed to the modification of local interactions mediated by the binding of maltodextrin since the tryptophan is not directly involved in any sugar-binding interaction.
Interventions for students with Attention-Deficit/Hyperactivity Disorder: One size does not fit all.

The following myths about the treatment of ADHD are dispelled: (a) ADHD has a presumed neurobiological basis; therefore, it can be treated only with medication; (b) all children with ADHD must be t...
Hematological profile among pulmonary tuberculosis patients in tertiary care hospital

Background : Tuberculosis is a major public health problem in India having variety of hematological manifestations. Aims and objectives: to investigate the changes of some hematological parameters in patients affected with pulmonary tuberculosis. Methods: All the smears were stained with Ziehl Neelsen stain by using standard protocol and blood were collected from patient into EDTA containers and tested on automated cell counter with complete profile. Result : Out of total 227 patients 179 (78.85%) were male and the larger prevalence among male patient was among age group 41-50 years (38.54%) and the larger prevalence among female patients was noted between the group 31-40 years (35.41%). The mean Hb level was 9.5g/dl, anaemia was found in 155(68.28%), leukocytosis in 65(28.63%), leucopenia in 5(2.20%), thrombocytosis in 40(17.62%), thrombocytopenia in 12(5.28%), ESR was found to be raised in 223(98.23%). Conclusion: patients infected with TB should be monitored haematologically in this study we found significant association of microscopic tuberculosis positive tuberculosis cases with raised ESR and anaemic patients.
Cell-free translation products of basement membrane RNA from the EHS tumor.

Abstract The biosynthetic products of the Engelbreth-Holm-Swarm (EHS) tumor and the cell-free translation products of EHS tumor cell RNA were characterized. Six distinct gene products (three laminin polypeptides, entactin/nidogen, and two collagen IV chains) comprising the basement membrane matrix were identified by a combination of proteolytic digestion and immunologic techniques. Analysis of the cell-free translation products using EHS tumor RNA precipitated by anti-laminin serum confirms earlier evidence that there are at least two B chains encoded by different genes. The anti-laminin serum also recognized entactin/nidogen, which was further identified by specific immunoprecipitation with anti-entactin serum. Radiolabeled laminin A chains, synthesized by the EHS tumor in organ culture, were also identified by the anti-laminin serum but were not detected among the cell-free translation products of EHS tumor RNA. Pulse-chase studies of EHS tumor in organ culture as well as in vitro translation of EHS tumor RNA suggest that the precursor forms of α1(IV) and α2(IV) collagen chains are nearly identical in size, with apparent molecular weights of 170 000. The mRNAs encoding these two polypeptides migrate differently on sucrose gradients. It is likely that glycosylation and hydroxylation of collagen IV account for the major differences in molecular weight of mature α1(IV) and α2(IV) chains in the EHS tumor matrix.
Sensory afferent and hypoxia-mediated activation of nucleus tractus solitarius neurons that project to the rostral ventrolateral medulla

The nucleus tractus solitarius (nTS) of the brainstem receives sensory afferent inputs, processes that information, and sends projections to a variety of brain regions responsible for influencing autonomic and respiratory output. The nTS sends direct projections to the rostral ventrolateral medulla (RVLM), an area important for cardiorespiratory reflexes and homeostasis. Since the net reflex effect of nTS processing ultimately depends on the properties of output neurons, we determined the characteristics of these RVLM-projecting nTS neurons using electrophysiological and immunohistochemical techniques. RVLM-projecting nTS neurons were identified by retrograde tracers. Patch clamp analysis in the horizontal brainstem nTS slice demonstrated that RVLM-projecting nTS cells exhibit constant latency solitary tract evoked excitatory postsynaptic currents (EPSCs), suggesting they receive strong monosynaptic contacts from visceral afferents. Three distinct patterns of action potential firing, associated with different underlying potassium currents, were observed in RVLM-projecting cells. Following activation of the chemoreflex in conscious animals by 3 h of acute hypoxia, 11.2±1.9% of the RVLM-projecting nTS neurons were activated, as indicated by positive Fos-immunoreactivity. Very few RVLM-projecting nTS cells were catecholaminergic. Taken together, these data suggest that RVLM projecting nTS neurons receive strong monosynaptic inputs from sensory afferents and a subpopulation participates in the chemoreflex pathway.
Technology and/as Governmentality: The Production of Young Rural Women as Low-Tech Laboring Subjects in China

This article presents an ethnography of a group of young women from rural China who attended a three-month computer-training course and then were placed in a data input company in China. Building upon scholarship on “Chinese governmentality,” I argue that although the training emphasized individual “quality” (suzhi) and the attainment of “useful” skills, once the women were employed their choices as autonomous individuals were severely limited through workplace disciplines that problematize notions of self government. I show how multiple modes of power were deployed to produce rural women as low-tech laboring subjects necessary for China's domestic development and participation in global capitalism.
Neutron transport in a reactor system with temperature feedback

Abstract When the effect of temperature feedback in a reactor system is considered the neutron transport equation for the neutron density is supplemented by a temperature equation which is a partial differential equation of parabolic type if heat conduction is taken into consideration. This consideration leads to a coupled system of nonlinear partial integro-differential equations. The aim of this paper is to present an iterative scheme for the determination of the solution of the nonlinear coupled system and to establish some qualitative property of the solution. The iterative scheme consists of two monotone sequences which converge monotonically from above and below, respectively, to a unique solution. The qualitative aspect includes the existence and uniqueness of a positive solution, upper and lower bounds of the solution and stability of a steady-state solution.
Thin-film approximate modeling of in-core fiber gratings

Generally tilted in-core fiber gratings are modeled by an equivalent inhomogeneous optical thin film. Its reflectance spectrum is evaluated using the multilayer and optical-path approximations. The re- sults are shown to be similar to those obtained using the exact local- normal mode method for the case of weak gratings. A fiber grating syn- thesis procedure is also introduced based on the methods advanced in this paper. © 1996 Society of Photo-Optical Instrumentation Engineers.
Modulation transfer function of layered inhomogeneous random media using the small-angle approximation.

Many random media such as clouds and fog are often inhomogeneously distributed and often have a layered structure. This paper presents the effects of such inhomogeneities on the image transmission in terms of the modulation transfer function (MTF). We derive an expression of the MTF for a layered inhomogeneous medium using the small-angle approximation which is valid for size parameters of >10 and optical distances of <5. We obtain numerical results and compare them with experimental data for different particle sizes and concentrations showing good agreement. We also explain the shower curtain effect using the expression for the MTF.
Glycoalkaloids as pest resistance factors

Potato glycoalkaloids, a class of steroid glycosides, possess antimicrobial and pesticidal properties. These phytochemicals have been implicated as natural resistance factors inSolanum species against the Colorado potato beetle,Leptinotarsa decemlineata Say, and the potato leafhopper,Empoasca fabae (Harris). Adverse effects of these secondary metabolites on insect behavioral and developmental biology are described, as well as considerations in manipulation of foliar glycoalkaloids in breeding for varietal resistance to insects.
Fragmentation of a forested Rocky Mountain landscape, 1950–1993

Abstract Patterns of change in landscape structure in a portion of the Hayden District of the Medicine Bow National Forest in southeastern Wyoming have been driven primarily by clearcut logging from 1950 to 1993; no major fires or wind storms have occurred in the study area during this time. Two distinct data sets, created from information in the Resource Information System database of the USDA Forest Service, were used as the basis for a quantitative analysis of landscape change. Forest fragmentation was quantified using a geographical information system (GRASS 4·1) to calculate indices of landscape structure. Increases in number of patches (1012 to 1331), total perimeter (3980 to 4400 km), Shannon diversity (2·36 to 2·63), contrast (2·49 to 2·68), and sum of edges (119·1 to 121·2 km) were accompanied by decreases in mean patch size (29·5 to 22·5 ha), mean patch shape (2·16 to 2·05), mean patch perimeter (3·91 to 3·3 km), dominance (1·04 to 0·81), contagion (4·30 to 4·07), and angular second moment (0·14 to 0·10). The observed trends in landscape pattern indicate increasing forest fragmentation since 1950. The study area landscape in 1993 is more fragmented than the landscape of the Oregon Cascades, now the subject of national attention and restoration action. As in other fragmented landscapes, the results suggest that previous management practices have lacked monitoring and analysis of landscape-scale impacts, indicating that increased attention to the landscape-scale is needed in future management actions.
Analysis of two purified mutants of Escherichia coli aspartate transcarbamylase with single amino acid substitutions

Two mutant versions of Escherichia coli aspartate transcarbamylase have been purified and analyzed kinetically. Each of these mutant enzymes contains a single amino acid different from the wild-type enzyme, which was introduced by suppression of a nonsense codon within the E. coli pyrB gene. These enzymes exhibited alterations in both homotropic and heterotropic interactions with little change in specific activity. Depending upon the site of the substitution, the allosteric interactions have been either enhanced or diminished over the wild-type enzyme. Carbamyl phosphate saturation curves indicate that aspartate and carbamyl phosphate homotropic co-operativity are separable. Experiments employing the allosteric effectors indicate that the transmission of the regulatory effect is dependent upon the structure of the catalytic subunit, and that CTP inhibition can be partially decoupled from ATP activation. The kinetics of one of the mutants is unusually sensitive to dissociation at elevated temperatures. This sensitivity may be due to weakened interactions between the subunits of the enzyme.
1125 NON-UTILITY OF HYPERALIMENTATION SURVEILLANCE CULTURES

Post-infusion hyperalimentation surveillance cultures (HC) are commonly obtained in many hospitals and have been routinely performed in our Special Care Unit (neonatal intensive care). We reviewed the microbiology records for the 1 year period from October 1983 through September 1984, to identify infants who were receiving hyperalimentation, and who had blood cultures (BC) for suspected sepsis. Thirty four patients who had been hyperalimented in that period had 101 BC. The incidence of positive BC was 15%. Two patients each had 2 organisms isolated from one BC. S. epidermidis (6/17) was the most common isolate. The same 34 patients had 1213 HC, 84 (0.7%) of which were positive: 3 for 2 organisms and 1 for 3 organisms. The most common organisms isolated were S. epidermidis 40/89, yeast 10/89 and enterococcus 8/89. The ability of routine HC to predict a subsequent episode of sepsis (positive BC) was studied. Two of 15 episodes of positive BC occurred subsequent to the isolation of the same organism from HC: sensitivity 0.13, specificity 0.94, predictive value of a positive HC 0.03, predictive value of a negative HC 0.98. The ability of concurrent (±24 hrs) HC to predict a positive BC was also studied. Five of 15 positive BC were accompanied by a positive HC: sensitivity 0.33, specificity 0.84, predictive value of a positive HC 0.26, predictive value of a negative HC 0.88. The annual cost of routine HC was $55,529. HC's are not effective predictors of positive BC and their routine use could substantially misdirect antimicrobial therapy. Concurrent HC and BC may be useful in establishing the pathogenesis of an infection.
Management of Pancreatic Fistulas

The management of pancreatic fistulas can be complex and mandates a multidisciplinary approach. Basic principles of fistula control/patient stabilization, delineation of ductal anatomy, and definitive therapy remain of paramount importance.
When do start-ups that exploit patented academic knowledge survive? ☆

Abstract Researchers have generally suggested that new technology firms should exploit radical technologies with broad scope patents to compete with established firms, implying that new firms founded to exploit university inventions will be more likely to survive in all industries if they possess these attributes. However, the existing empirical evidence indicates that the effectiveness of these two dimensions of new firm strategy is contingent on the industry environment, specifically industry concentration. In this paper, we explain why this industry-specific relationship should exist and use a unique data set of new technology ventures originating at Massachusetts Institute of Technology to test our arguments.
Alternate 5′ exons in the rat brain-derived neurotrophic factor gene: differential patterns of expression across brain regions

Brain-derived neurotrophic factor (BDNF) enhances the survival of dopaminergic neurons and protects them from neurotoxins in vitro. This trophic factor might thus be of therapeutic value for the treatment of Parkinsonian syndromes. The rat BDNF gene consists of several upstream noncoding exons that are alternatively spliced to a common coding exon. To investigate BDNF 5' exons expressed in the adult rat brain, we subjected RNA from cerebellum to 5'-RACE analysis and compared the resulting clones to previously reported 5' exon sequences from rat brain and hippocampus. In addition to known 5' exons, we isolated a BDNF transcript with a novel 5' sequence representing yet another alternate upstream exon in this gene. Quantitative PCR analysis of BDNF mRNAs containing each of the five upstream exons indicated that each of the alternate transcripts is most abundant in the hippocampus, intermediate in the substantia nigra and cerebellum and least abundant in the striatum. However, the magnitude of these differences in expression varied considerably suggesting that BDNF gene transcription in the mature brain is regulated by alternate promoters that are differentially active across regions.
Biochemical characterization of hydrolytic and oxidative enzymes in insecticide resistant and susceptible strains of the German cockroach (Dictyoptera: Blattellidae).

J. Econ. Entomol. 85(4): 1092-1098 (1992) ABSTRACT We have identified resistance mechanisms in the German cockroach, Blat- tella gemanica (L.), for propoxur and chlorpyrifos in strains of cockroaches that display multiresistance to several organophosphate and carbamate insecticides. The resistance mechanisms involve the combined effects of increased oxidative and hydrolytic metabo- lism and both strains are resistant to chlorpyrifos and propoxur. Experiments designed to test for similarity in metabolic enzymes suggest that, although the mechanisms involve similar processes, the enzymes responsible for insecticide detoxification are different in the two strains. Both resistant strains exhibited enhanced activity toward a-naphtholic esters relative to a standard susceptible strain; however, analysis of the progeny from resistant x susceptible crosses suggests that this general esterase activity is inherited differently than propoxur or chlorpyrifos resistance. Hybrids of the propoxur-resistant strain displayed the highest activity of all cockroaches tested, in contrast to hybrids of the chlorpyrifos-resistant strain, which were similar to the susceptible strain. Native gel elec- trophoresis of cytosolic preparations provided further evidence for differences in the pattern of hydrolytic enzymes and inheritance of resistance in the two strains. Analysis of components of the cytochrome P450-dependent monooxygenase system and activities toward model substrates indicate that the two resistance mechanisms also involve different oxidative processes. The propoxur-resistant strain displayed significantly higher levels of total cytochrome P450, but no other components were correlated with resistance. In contrast with the chlopyrifos-resistant strain, which was similar to the susceptible strain in all parameters measured, activity toward model substrates was higher in the propoxur- resistant strain than in any of the other strains and hybrids tested. Progeny of the suscep- tible and propoxur resistant crosses displayed similar levels of monooxygenase compo- nents to the susceptible strain, indicating that increased oxidative metabolism is a recessive trait in the Baygon-R strain.
Infection of primary African green monkey cells with SV40 monomeric and dimeric DNA.

Abstract Primary African green monkey cells were infected with purified monomeric and dimeric SV40 DNA. The main covalently closed circular DNA synthesized after infection with monomers were SV40 monomers, whereas after infection with dimers predominantly dimeric SV40 DNA was synthesized. This result demonstrates that SV40 dimeric DNA can replicate and argues against a dimeric intermediate in the normal replication of SV40 DNA.
Computer vision aided target linked radiation imaging

In this paper, we demonstrated an application of video tracking to radiation detection, where a vision-based tracking system enables a traditional CZT (cadmium zinc telluride)-based radiation imaging device to detect radioactive targets that are in motion. An integrated real-time system consisting of multiple fixed cameras and radiation detectors was implemented and tested. The multi-camera tracking system combines multiple feature cues (such as silhouette, appearance, and geometry) from different viewing angles to ensure consistent target identities under challenging tracking conditions. Experimental results show that both the video tracking and the integrated systems perform accurately and persistently under various scenarios involving multiple vehicles, driving speeds, and driving patterns. The results also validate and reiterate the importance of video tracking as an enabling technology in the field of radiation imaging.
Studies on itraconazole delivery and pharmacokinetics in mallard ducks (Anas platyrhynchos)

Avian aspergillosis is commonly treated with itraconazole (ITZ). This paper describes two studies using mallard ducks (Anas platyrhynchos). The first study evaluated in vivo release of ITZ from subcutaneously injected controlled-release gel formulations and the second study compared pharmacokinetic parameters for two ITZ oral suspensions. ITZ-A suspension was prepared by mixing contents of commercially available capsules with hydrochloric acid and orange juice. ITZ-B suspension was prepared by dispersing the complex of the drug with hydroxypropyl-beta-cyclodextrin in water. Concentrations of ITZ and its active metabolite, hydroxyitraconazole (OH-ITZ), in plasma and tissue samples were measured using high-performance liquid chromatography. In the second study, drug concentrations in plasma samples were also analyzed using a bioassay. After administration of two ITZ controlled-release formulations, plasma and tissue concentrations of ITZ and OH-ITZ were either very low (< or = 52 ng/mL) or undetectable. Exceptions included skin, subcutaneous fat, and muscle adjacent to the injection site. The drug from ITZ-A and ITZ-B suspensions was absorbed after oral administration. ITZ pharmacokinetic parameters for both suspensions in mallard ducks were similar and the bioassay successfully measured ITZ equivalents in plasma samples from ducks.
P50 suppression among schizophrenia and normal comparison subjects: a methodological analysis.

The present report investigated the relationship between P50 suppression and habituation among 20 schizophrenia and 20 normal comparison subjects. Subjects were presented with clicks delivered over headphones in a S 1 –S 2 paradigm (clicks were separated by 500 msec; average intertrial interval was 8 sec). There were 60 total trials; the data were analyzed separately for the first and second 30 trials. The groups did not differ either on the number of usable trials or on the morphology of their P50 responses. Consistent with previous reports, schizophrenia patients demonstrated deficient P50 suppression. The overall suppression effect was not due to a group difference on S 1 P50 amplitudes, but was associated with schizophrenia patients having smaller S 1 – S 2 P50 amplitude difference scores than normal comparison subjects. Furthermore, the suppression effect appears to be more pronounced during the first than during the second block of trials. Thus, it may be important to evaluate changes in P50 responses over time among schizophrenia and normal comparison subjects.