cssi/SciSciGPT-SciSciNet huggingface dataset:
A longitudinal investigation of the association between rumination, hostility, and PTSD symptoms among trauma-exposed individuals.

Abstract Background Rumination, defined as perseverative thinking regarding the causes and consequences of psychological symptoms, is a risk and maintaining factor for PTSD. Existing work has largely focused on the extent to which rumination functions as a coping strategy used to avoid traumatic memories and associated emotions. However, rumination may also maintain negative thinking patterns, such as hostility, which has been positively associated with both rumination and PTSD symptoms. The current study therefore investigated the extent to which hostility was a significant mediator of the prospective association between rumination and PTSD symptoms. Methods The sample consisted of 119 trauma-exposed individuals (48.7% female), who completed self-report questionnaires at three time points during a clinical trial. Results When controlling for treatment condition and baseline depressive disorder diagnosis, hostility temporally mediated the effects of rumination on PTSD symptoms. Specificity analyses provided further support for the direction and specific variables examined in this model, such that rumination was positively and uniquely associated with later hostility. Limitations Our findings are limited by the use of a sample in which only 30% of participants met diagnostic criteria for a trauma-related disorder, as well as the administration of the rumination measure at only one time point. Conclusions Results suggest that rumination and hostility may be promising treatment and prevention targets for PTSD symptoms.
Systems Engineering Graduate Research as Part of Curriculum – Summary of Research

Abstract In this paper, we review and analyze the systems engineering graduate research projects that students have completed as part of their curriculum requirement. The information presented here is gathered over five years. The semester long projects are completed as part of the graduate course titled ‘System Development Workshop’ taught at Southern Polytechnic State University (SPSU). Students are required to investigate a discipline-related topic in systems engineering in the form of capstone project. The general intent of the project is to give students an opportunity towards the end of their Master's degree courses, to demonstrate and apply the knowledge they have acquired over the course of the curriculum. The work performed in the project draws upon skills and knowledge acquired in the program. Students are required to identify an engineering problem, often in their work environment, and use systems engineering methods to achieve a solution to the problem. At the end of the study, each student prepares a formal report describing the work performed, resulting conclusions and recommendations. In addition, students present their results to the online audience. Students are expected to meet professional engineering standards in their work and reports. The results of the projects are considered for submission to an academic conference or journal in the field. This course gives students, often times their first, taste of research. The intent of this paper is to demonstrate several examples of research projects completed by students and to investigate the efficacy of a research based course in Systems Engineering graduate curriculum.
Physician Wellness During a Pandemic.

INTRODUCTION: We are currently in the midst of the coronavirus disease 2019 (COVID-19) pandemic. Research into previous infectious disease outbreaks has shown that healthcare workers are at increased risk for burnout during these dire times, with those on the front lines at greatest risk. The purpose of this prospective study was to determine the effect that the COVID-19 pandemic has had on the wellness of emergency physicians (EP). METHODS: A survey was sent to 137 EPs in a multi-hospital network in eastern Pennsylvania. We compared 10 primary and two supplemental questions based on how the physicians had been feeling in the prior 2-3 weeks (COVID-19 period) to the same questions based on how they were feeling in the prior 4-6 months (pre-COVID-19 period). RESULTS: We received 55 responses to the survey (40.1% response rate). The study found that during the pandemic, EPs felt less in control (p-value = 0.001); felt decreased happiness while at work (p-value 0.001); had more trouble falling asleep (p-value = 0.001); had an increased sense of dread when thinking of work needing to be done (p-value = 0.04); felt more stress on days not at work (p-value <0.0001); and were more concerned about their own health (p-value <0.0001) and the health of their families and loved ones (p-value <0.0001). CONCLUSION: This study showed a statistically significant decrease in EP wellness during the COVID-19 pandemic when compared to the pre-pandemic period. We need to be aware of evidence-based recommendations to help mitigate the risks and prevent physician burnout.
Distributional Preferences in Larger Groups: Keeping up with the Joneses and Keeping Track of the Tails

We study distributional preferences in âlargeâ groups. While most prior experi- ments have focused on exploring attitudes toward inequality in two- or three-person groups, we field a series of experiments via Mechanical Turk in which subjects choose between two income distributions, each with seven (or nine) individuals, with hypo- thetical incomes that aim to approximate the actual distribution of income in the U.S. Our setting thus provides a more direct comparison to the redistributive choices faced by society. Consistent with standard maximin (Rawlsian) preferences, subjects select distributions in which the bottom individualâs income is higher (but show little regard for lower incomes above the bottom ranking). In contrast to standard models, however, we find that subjects select distributions that lower the top individualâs income, but not other high incomes. Finally, we provide tentative evidence of âlocally competitiveâ preferencesâin most experimental sessions, subjects select distributions that lower the income of the individual directly above them, while the income of the individual two positions above has little effect on subjectsâ decisions. Our findings suggest that the- ories of inequality aversion should be enriched to account for individualsâ aversion to âtopmostâ and âlocalâ disadvantageous inequality.
A Framework for Understanding the Association Between Training Paradigm and Trainee Preparedness for Independent Surgical Practice

Importance The sociopolitical and cultural context of graduate surgical education has changed considerably over the past 2 decades. Although new structures of graduate surgical training programs have been developed in response and the comparative value of formats are continually debated, it remains unclear how different time-based structural paradigms are preparing trainees for independent practice after program completion. Objective To investigate the factors associated with trainees’ and program directors’ perception of trainee preparedness for independent surgical practice. Design, Setting, and Participants This qualitative study used an instrumental case study approach and obtained information through semistructured interviews, which were analyzed using open-and-focused coding. Participants were recent graduates and program directors of vascular surgery training programs in the United States. The 2 training paradigms analyzed were the integrated vascular surgery residency program (0 + 5, with 0 indicating that the general surgery training experiences are fully integrated into the 5 years of overall training and 5 indicating the total number of years of training) and the traditional vascular surgery fellowship program (5 + 2, with 5 indicating the number of years of general surgery training and 2 indicating the number of years of vascular surgery training). All graduates completed their training in 2018. All interviews were conducted between July 1, 2018, and September 30, 2018. Main Outcomes and Measures A conceptual framework to inform current and ongoing efforts to optimize graduate surgical training programs across specialties. Results A total of 22 semistructured interviews were completed, involving 7 graduates of 5 + 2 programs, 9 graduates of 0 + 5 programs, and 6 vascular surgery program directors. Of the 22 participants, 15 were men (68%). Participants described 4 interconnected domains that were associated with trainees’ perceived preparedness for practice: structural, individual, relational, and organizational. Structural factors included the overall and vascular surgery–specific time spent in training, whereas individual factors included innate technical skills, confidence, maturity, and motivation. Faculty-trainee relationships (or relational factors) were deemed important for building trust and granting of autonomy. Organizational factors included features of the local organization, including patient population, case volume, and case mix. Conclusions and Relevance Findings suggest that restructuring training paradigms alone is insufficient to address the issue of trainees’ perceived preparedness for practice. A framework was created from the results for evaluating and improving residency and fellowship programs as well as for developing graduate surgical training paradigms that incorporate all 4 domains associated with preparedness.
Thinking politically about scholarly infrastructure: Commit the publishers to 2.5%

Maybe it’s unsurprising that I think about scholarly communication in terms similar to U.S. politics. I originally drafted this article for the Library Publishing Coalition blog before the 2020 election and revised it for C&RL News during the weirdly long interregnum period before the actual inauguration. The 2016 Republican National Committee was the backdrop to my becoming a scholarly communication librarian in February of that year. That’s also when I joined Twitter, to better follow politics and librarianship, and maybe that’s to blame.
Futurs utopiques et dystopiques : Comment la fiction aide à penser l’évolution

Cet article aborde le theme des futurs utopiques et dystopiques tel qu'il nous est transmis a travers la philosophie et la fiction (litterature et cinema), et montre comment ces notions nous aident a penser l'evolution. Il propose une exploration historique des termes « utopie » et « dystopie », agrementee d'exemples appartenant a la litterature, a la philosophie et au cinema. L'article souligne aussi l'importance de rehabiliter l'utopie comme moyen d'inventer un futur radicalement different.
hNOP2/NSUN1 Regulates Ribosome Biogenesis through Stabilization of snoRNP Complexes and Cytosine-5 Methylation of 28S rRNA

5-Methylcytosine (m5C) is a base modification broadly found on a variety of RNAs in the human transcriptome. In eukaryotes m5C is catalyzed by enzymes of the NSUN family, which is composed of seven members in humans (NSUN1-7). NOP2/NSUN1 has been mostly characterized in budding yeast as an essential ribosome biogenesis factor required for the deposition of m5C on the 25S rRNA. Although human NOP2/NSUN1 has been known to be an oncogene overexpressed in several types of cancer, its functions remain poorly characterized. To define the roles of human NOP2/NSUN1, we used an miCLIP-seq approach to identify its RNA substrates. Our analysis reveals that vault RNA 1.2 and rRNA are NOP2/NSUN1-specific methylated targets and we further confirm by bisulfite sequencing that NOP2/NSUN1 is responsible for the deposition of m5C at residue 4447 on the 28S rRNA. Depletion of NOP2/NSUN1 impairs cell proliferation, rRNA processing and 60S ribosome biogenesis. Additionally, we find that NOP2/NSUN1 binds to the 5′ETS region of the pre-rRNA transcript and regulates pre-rRNA processing in part through non-catalytic complex formation with box C/D snoRNAs. Our study identifies for the first time the RNA substrates of human NOP2/NSUN1 and reveals additional functions in rRNA processing beyond catalyzing m5C base modification.
Activated immune response in an inherited leukodystrophy disease caused by the loss of oligodendrocyte gap junctions

Oligodendrocyte:oligodendrocyte (O:O) gap junction (GJ) coupling is a widespread and essential feature of the CNS, and is mediated by connexin47 (Cx47) and Cx32. Loss of function mutations affecting Cx47 results in a severe leukodystrophy, Pelizeus-Merzbacher-like disease (also known as Hypomyelinating Leukodystrophy 2), which can be reproduced in mice lacking both Cx47 and Cx32. Here we report the gene expression profile of the cerebellum--an affected brain region--in mice lacking both Cx47 and Cx32. Of the 43,174 mRNA probes examined, we find decreased expression of 23 probes (corresponding to 23 genes) and increased expression of 545 probes (corresponding to 348 genes). Many of the genes with reduced expression map to oligodendrocytes, and two of them (Fa2h and Ugt8a) are involved in the synthesis of myelin lipids. Many of the genes with increased expression map to lymphocytes and microglia, and involved in leukotrienes/prostaglandins synthesis and chemokines/cytokines interactions and signaling pathways. In accord, immunostaining showed T- and B-cells in the cerebella of mutant mice as well as activated microglia and astrocytes. Thus, in addition to the loss of GJ coupling, there is a prominent immune response in mice lacking both Cx47 and Cx32.
Housing Segregation in Suburban America since 1960: Presidential and Judicial Politics

1. Separate worlds, separate lives 2. Lyndon Johnson and the Fair Housing Act 3. George Romney's blueprint for suburban integration 4. Richard Nixon, centralization, and the policymaking process 5. Suburban segregation from Gerald Ford to Bill Clinton 6. The Federal courts and suburban segregation 7. Conclusions.
Avoiding Online Predators: Proactive Measures Companies Can Take to Protect Their Female Consumers

3 Spring 2015 BA 495 Client 3 What is Social Discovery? 4 Literature Review 4 Online/Offline Concerns 5 Online Victimization 6 Who are Possible Victims 7 Industry Report 7 Sexual Assault on Women & Teens 8 Social Media and the Law 9 Three Case Studies 9 Case 1 Carly Ryan 10 Case 2 Skout; a Flirting App 10 Case 3 Predators Using Online Dating Target Women 12 Risk Management Approach 12 Market Research: Competitor Disclosures (Reactive) 14 Competitor 1 MeetUp 15 Competitor 2 Tinder 15 Security Recommendations (Proactive) 16 References 19
Task-dependent nature of fatigue in single motor units

The loss of force production during sustained activity presents the CNS a unique control problem. Different tasks stress the neuromuscular system at different sites and times, and involve different cellular mechanisms. The functional organization of muscles and their motor units has evolved to avoid fatigue processes that impair motor performance. The purpose of this brief review is to examine the fatigue properties of type-identified motor units and to speculate what these properties reveal about the organization and control of muscle.
Habitat selection of Merriam's Turkey ( Meleagris gallopavo merriami ) hens with poults in the Black Hills, South Dakota

We studied habitat selection patterns of Merriam's Turkey (Meleagris gallopavo merriami) hens with poults in a ponderosa pine (Pinus ponderosa) ecosystem. Thirty-six radio-marked hens produced 19 broods, and we obtained 230 locations of hens with poults. We described vegetation of habitats using criteria from the Rocky Mountain Region, U.S. Forest Service, for determining effects of forest management and monitoring of wildlife populations. Most habitat units were 432 ha and corresponded to third-order habitats as described by Johnson (1980). Hens with poults selected large meadows and rarely selected dense ponderosa pine habitats. Younger poults used meadows more frequently than did older poults. Implementation of the Black Hills National Forest Land and Resource Management Plan in ponderosa pine habitats will not negatively impact hens with poults. Grazing by livestock reduces herbaceous biomass necessary for invertebrate food items of poults and cover for poults. Habitat selection patterns of hens with poults should be evaluated by age categories of points.
The Partial Amino Acid Sequence of Human Myoglobin

Tryptic and chymotryptic digests of human myoglobin have been separated chromatographically to give 23 pure tryptic peptides and 18 pure chymotryptic peptides. The complete or partial amino acid sequences of these peptides have been established. From the overlaps in sequence between chymotryptic and tryptic peptides it is possible to place 124 of the 152 residues of human myoglobin in a unique sequence. The remaining residues have been ordered tentatively on the basis of the apparent homology in sequence between human and sperm whale myoglobins. Human myoglobin appears to contain 152 residues instead of 153 residues as found in whale myoglobin. The sequence of human myoglobin appears to be accommodated easily into the proposed three-dimensional structure of whale myoglobin, and large differences in the conformation of these two myoglobins cannot be expected.
Electrolysis of Alumina in a Molten Salt at 760°C

The electrolysis of alumina at a current density of 0.9 A/cm2 in a predominantly chloride electrolyte at 760°C has been demonstrated on bench scale. A high surface area anode was used to achieve this result.
Translational and rotational mode coupling in disordered ferroelectric KTa1-xNbxO3 studied by Raman spectroscopy

Abstract The coupling of translational modes to the reorientational motion is an essential property of systems with internal orientational degrees of freedom. Due to their high complexity most of those systems (molecular crystals, glasses, etc.) present a major puzzle for scientists. In this paper we analyze the Raman scattering of a relatively simple ferroelectric system, KTa 1− x Nb x O 3 , which may serve as a model for more complicated cases. We show the presence of a strong coupling between translational and reorientational motion in the crystal. Our data suggest that this coupling is the main reason for the depolarized component of the second-order Raman spectra and that it is also responsible for the frequency decrease (softening) of the transverse acoustic mode down to the third of three transitions, below which reorientational motion is no longer allowed.
Regulators of G Protein Signaling (RGS Proteins)

This article has no abstract. Keywords: regulators of g protein signaling (rgs proteins)
Pair programming and agile software development: experiences in a college setting

While agile software development methodologies are now becoming more commonplace in industry, they have yet to be fully embraced by academic institutions. To better prepare university students for the marketplace, it is important that students are familiar with these alternative software development methods. For those unacquainted with agile methodologies, this paper first provides a summary of agile practices and a review of reports on teaching these practices in college classrooms. Next it discusses a study that the authors conducted in a graduate course entitled Software Development Process Models, in which the students were required to use eXtreme Programming practices. The discussion describes course assignments and the results from a survey that was administered to assess students' perceptions of their experiences using pair programming and agile methods.
Neural Processing of Gravito-Inertial Cues in Humans. I. Influence of the Semicircular Canals Following Post-Rotatory Tilt

Sensory systems often provide ambiguous information. Integration of various sensory cues is required for the CNS to resolve sensory ambiguity and elicit appropriate responses. The vestibular system includes two types of sensors: the semicircular canals, which measure head rotation, and the otolith organs, which measure gravito-inertial force (GIF), the sum of gravitational force and inertial force due to linear acceleration. According to Einstein's equivalence principle, gravitational force is indistinguishable from inertial force due to linear acceleration. As a consequence, otolith measurements must be supplemented with other sensory information for the CNS to distinguish tilt from translation. The GIF resolution hypothesis states that the CNS estimates gravity and linear acceleration, so that the difference between estimates of gravity and linear acceleration matches the measured GIF. Both otolith and semicircular canal cues influence this estimation of gravity and linear acceleration. The GIF resolution hypothesis predicts that inaccurate estimates of both gravity and linear acceleration can occur due to central interactions of sensory cues. The existence of specific patterns of vestibuloocular reflexes (VOR) related to these inaccurate estimates can be used to test the GIF resolution hypothesis. To investigate this hypothesis, we measured eye movements during two different protocols. In one experiment, eight subjects were rotated at a constant velocity about an earth-vertical axis and then tilted 90 degrees in darkness to one of eight different evenly spaced final orientations, a so-called "dumping" protocol. Three speeds (200, 100, and 50 degrees /s) and two directions, clockwise (CW) and counterclockwise (CCW), of rotation were tested. In another experiment, four subjects were rotated at a constant velocity (200 degrees /s, CW and CCW) about an earth-horizontal axis and stopped in two different final orientations (nose-up and nose-down), a so-called "barbecue" protocol. The GIF resolution hypothesis predicts that post-rotatory horizontal VOR eye movements for both protocols should include an "induced" VOR component, compensatory to an interaural estimate of linear acceleration, even though no true interaural linear acceleration is present. The GIF resolution hypothesis accurately predicted VOR and induced VOR dependence on rotation direction, rotation speed, and head orientation. Alternative hypotheses stating that frequency segregation may discriminate tilt from translation or that the post-rotatory VOR time constant is dependent on head orientation with respect to the GIF direction did not predict the observed VOR for either experimental protocol.
Attachment of transported vesicles to microtubules in axoplasm is facilitated by AMP-PNP

Axoplasm extruded from the squid giant axon has been used to analyse the molecular mechanisms of intracellular vesicle transport1,2. Using video-enhanced light microscopy, vesicle transport can be observed directly on individual microtubules at the edge of the axoplasm2–4. Here we report that AMP-PNP (adenyl-5′-yl imidodiphosphate), a non-hydrolysable analogue of ATP, reversibly inhibited vesicle transport. Moreover, vesicles in solution attach to the microtubules and form relatively stable complexes. AMP-PNP may produce this effect by binding to an ATP-binding site on the transport machinery, thereby stabilizing the motility complex that is normally formed by a transported vesicle, an ATPase and a microtubule. The effects of AMP-PNP on the vesicle transport system indicate that the enzymatic machinery of this system differs significantly from that of the actomyosin system or the dynein–microtubule system.
Shared effects of genetic and intrauterine and perinatal environment on the development of metabolic syndrome.

Genetic and environmental factors, including the in utero environment, contribute to Metabolic Syndrome. Exposure to high fat diet exposure in utero and lactation increases incidence of Metabolic Syndrome in offspring. Using GLUT4 heterozygous (G4+/−) mice, genetically predisposed to Type 2 Diabetes Mellitus, and wild-type littermates we demonstrate genotype specific differences to high fat in utero and lactation. High fat in utero and lactation increased adiposity and impaired insulin and glucose tolerance in both genotypes. High fat wild type offspring had increased serum glucose and PAI-1 levels and decreased adiponectin at 6 wks of age compared to control wild type. High fat G4+/− offspring had increased systolic blood pressure at 13 wks of age compared to all other groups. Potential fetal origins of adult Metabolic Syndrome were investigated. Regardless of genotype, high fat in utero decreased fetal weight and crown rump length at embryonic day 18.5 compared to control. Hepatic expression of genes involved in glycolysis, gluconeogenesis, oxidative stress and inflammation were increased with high fat in utero. Fetal serum glucose levels were decreased in high fat G4+/− compared to high fat wild type fetuses. High fat G4+/−, but not high fat wild type fetuses, had increased levels of serum cytokines (IFN-γ, MCP-1, RANTES and M-CSF) compared to control. This data demonstrates that high fat during pregnancy and lactation increases Metabolic Syndrome male offspring and that heterozygous deletion of GLUT4 augments susceptibility to increased systolic blood pressure. Fetal adaptations to high fat in utero that may predispose to Metabolic Syndrome in adulthood include changes in fetal hepatic gene expression and alterations in circulating cytokines. These results suggest that the interaction between in utero-perinatal environment and genotype plays a critical role in the developmental origin of health and disease.
Salt After Adrenalectomy. I. Growth and Survival of Adrenal-ectomized Rats Given Various Levels of NaCl.∗

SummaryA daily intake of 650 to 940 mg NaCl for an adult adrenalectomized rat seems to be “optimal” in maintaining growth and apparent health. A daily intake of 339 mg is not sufficient for growth or survival. Large amounts of NaCl such as 1200 mg a day are injurious.
Enzymatic synthesis of poly(ε-caprolactone): thermal properties, recovery, and reuse of lipase B from Candida antarctica immobilized on macroporous acrylic resin particles

Candida is a genus of yeast, and lipase B isolated from Candida antarctica (CALB) has been utilized as a biocatalyst for the synthesis of a variety of organic compounds including polyesters and polylactones. Among the various immobilization media reported in the literature, the porous acrylic resin utilized in Novozym-435 has been widely studied. Here, we report the enzyme recovery and reuse for the synthesis of poly(e-caprolactone) in toluene at 70 °C for 4 h per cycle for up to 10 reaction cycles, which consistently resulted in polymers with a weight-average molecular weight, M w , of ~50,000 g mol−1 and a polydispersity index of ~1.4. In addition, the thermal properties of the resin particles used in Novozym-435, with and without the enzyme, were evaluated by TGA and DSC analysis. The effect of mechanical agitation on the enzyme stability, recovery, and reuse was also discussed. These results may have significance to enzymatic polymer synthesis as well as to the enzyme immobilization on acrylic resins and other matrices.
Consumer Perception of Country-of-Origin Effect and Brand Effect

Abstract Both brand information and country-of-origin information are often used by consumers to reduce the complexity of task involved in information processing. This paper investigates both effects on hi-tech products. I find that, overall, both country-of-origin effect and brand effect are statistically significant. However, the brand name product with an unfavorable country-of-origin image does not lose its advantage compared to the brand name product with a favorable country-of-origin image. The no-name product with a favorable country-of-origin image can offset the disadvantage of not being the brand name product.
The response of pancreatic and pituitary hormones to pulses and constant infusion of somatostatin.

The inhibitory action of pulses and constant infusion of somatostatin on the secretion of pancreatic and pituitary hormones was studied serially in 7 normal men and 2 untreated acromegalies. In normal men, significant inhibition of basal release of insulin and glucagon was elicited by as little as 1 μg dose of a pulse of somatostatin. Increasing doses of somatostatin (5, 50, 250 and 500 μg) given as a single pulse at weekly intervals produced what appears to be a decreased inhibition of glucagon while no measurable relationship between the dose of somatostatin and the degree of inhibition of insulin was seen. Given during the same day, incremental doses (from L to 250 μg) of pulses of somatostatin produced a progressive decline in both glucagon and insulin. The elevated basal levels of GH, insulin and glucagon seen in acromegalies, were inhibited by a pulse of somatostatin as little as 2 μg. These inhibitions were sustained during the constant infusion of somatostatin (2.5 μg/min), and are bound in GH, in...
False recognition and word length: A reanalysis of Roediger, Watson, McDermott, and Gallo (2001) and some new data

Roediger, Watson, McDermott, and Gallo (2001) reported a multiple regression analysis of the variables that predicted rates of false recall and recognition across lists in the Deese/Roediger— McDermott paradigm. They concluded that false recollection was predictable from the backward associative strength of critical words and list words and the veridical recall level of list words, with no independent contribution of frequency, concreteness, or length of critical words. A reanalysis of their data shows that critical word length does contribute to false recognition when it is measured relative to the length of other words in the list. Relative word length in the form of an unsignedz-score has a larger correlation with false recognition than any of the variables used by Roediger et al. and is also independently predictive of false recognition. This relationship was confirmed by the results of two recognition experiments in which false positives were significantly less frequent for words of lengths that never occurred in a studied list than for words of lengths that did occur in the study list.
Content coverage of animal behavior data

This paper describes the results of analysis and visualization of Animal Behavior research papers pulbished in major journals. Analysis is carried out to obtain associations among the citation records for the domain. The primary goal is to observe the content coverage and the prominent research areas and describe the research activities taking place over the past decade. The methodologies used to study the domain provide a potential platform that can be extended to cover the entire publication history of the domain. The fact that the field of Animal Behavior has remained uncharted to a great extent provides immense motivation for the study.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Characterization of an inward current elicited by edrophonium in physically isolated and internally perfused Aplysia neurons

We have studied the ionic and pharmacological properties of an inward current elicited by edrophonium, a cholinesterase inhibitor, on physically isolated and internally perfused Aplysia neurons using the voltage clamp, internal perfusion and rapid external perfusion techniques. The current amplitude was dependent on the external Na concentration [(Na)o] in an almost linear manner. However, complete replacement of (Na)o with Tris or sucrose failed to abolish the current. Internal application of Na [increased (Na)i] reduced the current amplitude. In normal (Na)o, changing (Ca)o (both increases and decreases in (Ca)o) reduced the current amplitude. In the sucrose-substituted (Na)o-free condition, edrophonium still could cause a small current (less than 5% of the control). However, an increased (Ca)o did not augment this residual current. Cs and Li carried the edrophonium-activated current when substituted for (Na)o. With sucrose-substituted Na-free sea water outside, edrophonium elicited an outward current when the neuron was internally perfused with Cs, but not when the neuron was internally perfused with K. Therefore, it is unlikely that K is permeant. External application of tetrodotoxin, a blocker of voltage-dependent Na channels, external application of Cd and internal application of F did not affect the current. The edrophonium response was most sensitive to strychnine, which was about 10 times more potent than D-tubocurarine. Hexamethonium, however, had no effect. The local anesthetics, lidocaine and procaine, inhibited the response over the same concentration range as D-tubocurarine. We conclude that edrophonium opens a monocationic channel (presumably a type of Na channel) which is sensitive to (Ca)o.(ABSTRACT TRUNCATED AT 250 WORDS)
Symbolic dynamics of tree maps

The symbolic dynamics of a class of tree maps is analysed. There are three symbolic dynamical systems associated to such a map. They can best be understood in terms of sofic systems, which are generalizations of subshifts of finite type. Several examples are provided to illustrate these ideas.
Effects of Decreased Hydrophobicity above R1 in S4-Based Voltage Sensors

Membrane proteins containing S4-based voltage sensors domains (VSD) respond to changes in the membrane potential by transferring electrically charged side chains (gating charges), mainly located in the S4 segment, across the membrane electric field. The region just above the first charge (R1) is generally thought to control the VSD voltage-dependence. Here, we decreased residue hydrophobicity between N353 to L361 just above R1 in the Shaker Kv channels and found that for the two positions L358 and L361, less hydrophobic residues dramatically shifted the Charge vs. Voltage (Q-V) curve to more negative voltages, up to −132 mV. Screening L358 with several amino acids revealed a linear correlation between the side chain hydrophobicity and the Q-V curve midpoint. Interestingly, structural models of the VSD place the L358 and L361 side chains towards the hydrophobic core of the lipid bilayer in a resting state and towards the aqueous solvent in the active state, suggesting that less hydrophobic mutants may destabilize the resting state and/or stabilize the active state. To explore the origins of these phenotypes, we co-mutated some hydrophilic point mutations at position 358 or 361 together with the ILT mutation, which uncouples VSD movement from pore opening. Our results indicate that most double mutants shifts further the Q-V curves compared to the point mutations, but did not shift the G-V curves compared to the ILT mutant, suggesting that hydrophilic substitutions at positions 358 and 361 most likely destabilized the VSD resting state. Support: NIH-GM030376.
Angiotensin II type 1 receptor activation increases microvascular permeability via a calcium dependent process1

Background Elevated serum angiotensin II (Ang II) has been implicated in the endothelial barrier dysfunction associated with shock. We hypothesized that the increase in microvascular permeability seen with activation of the type 1 (AT1) receptor is a calcium dependent process. Materials and methods Microvascular hydraulic permeability (Lp) was measured in rat mesenteric venules using the Landis micro-occlusion model. A 100 mm KCl (HK) solution was used to negate the electrochemical potential of calcium influx, and measures of Lp were obtained before and after 20 ng/ml Ang II plus HK solution (n = 5). Intracellular calcium dependence on AT1 activation was evaluated two ways: 1) Lp changes were measured in response to 10 μm of the type 1 receptor agonist [SAR] [ 1 ]-angiotensin II in HK solution (n = 6), and 2) Lp changes were measured in response to 25 μg/ml of the type 2 (AT2) receptor blocker PD-123319 (PD) plus 20 ng/ml Ang II in HK solution (n = 6). Results As expected, HK perfusion (P 1 ]-angiotensin II in HK solution (P Conclusions Abrogation of intracellular calcium influx during AT1 activation blunted the known Ang II induced increase in microvascular permeability. Although the effect observed during AT1 activation was blunted by the HK solution, a significant elevation of Lp was still observed. This suggests that Ang II activation of the AT1 receptor increases microvascular permeability primarily, but not exclusively, via modulation of endothelial intracellular calcium ion levels.
Derivation of S and Pb in Phanerozoic Intrusion-Related Metal Deposits from Neoproterozoic Sedimentary Pyrite, Great Basin, United States

The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ 34 S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes ( 207 Pb/ 204 Pb >19.2; 15 analyses) acquired from clastic detritus eroded from Precambrian cratonal rocks to the east-southeast. In the overlying Paleozoic section, Pb-Zn-Cu-Ag-Au deposits associated with Jurassic, Cretaceous, and Tertiary granitic intrusions (intrusion-related metal deposits) contain galena and other sulfide minerals with S and Pb isotope compositions similar to those of TDS sedimentary pyrite, consistent with derivation of deposit S and Pb from TDS pyrite. Minor element abundances in TDS pyrite (e.g., Pb, Zn, Cu, Ag, and Au) compared to sedimentary and hydrothermal pyrite elsewhere are not noticeably elevated, implying that enrichment in source minerals is not a precondition for intrusion-related metal deposits. Three mechanisms for transferring components of TDS sedimentary pyrite to intrusion-related metal deposits are qualitatively evaluated. One mechanism involves (1) decomposition of TDS pyrite in thermal aureoles of intruding magmas, and (2) aqueous transport and precipitation in thermal or fluid mixing gradients of isotopically heavy S, radiogenic Pb, and possibly other sedimentary pyrite and detrital mineral components, as sulfide minerals in intrusion-related metal deposits. A second mechanism invokes mixing and S isotope exchange in thermal aureoles of Pb and S exsolved from magma and derived from decomposition of sedimentary pyrite. A third mechanism entails melting of TDS strata or assimilation of TDS strata by crustal or mantle magmas. TDS-derived or assimilated magmas ascend, decompress, and exsolve a mixture of TDS volatiles, including isotopically heavy S and radiogenic Pb from sedimentary pyrite, and volatiles acquired from deeper crustal or mantle sources. In the central and eastern Great Basin, the wide distribution and high density of small to mid-sized vein, replacement, and skarn intrusion-related metal deposits in lower Paleozoic rocks that contain TDS sedimentary pyrite S and Pb reflect (1) prolific Jurassic, Cretaceous, and Tertiary magmatism, (2) a regional, substrate reservoir of S and Pb in permeable and homogeneous siliciclastic strata, and (3) relatively small scale concentration of substrate and magmatic components. Large intrusion-related metal deposits in the central and eastern Great Basin acquired S and most Pb from thicker lithospheric sections.
Mechanism of superconductivity in K3C60.

Abstract Using electronic states and phonon states from the first-principles calculations and including both conventional electron-phonon charge coupling and Jahn-Teller coupling, we predict Tc and other superconducting properties. The only adjustable parameter in the theory is the screening length, Rsc. Using Rsc = 0.8-1.0 A, we find excellent agreement with experiment for Tc (16-18 K), pressure dependence of Tc (Delta Tc = -6 to -10 K for 1 GPa), and 12 C to 13 C isotope shift (alphaC = 0.2); experimental values: 19 K, -7 K, and 0.3, respectively.
Atomic layer deposition of tin oxide films using tetrakis(dimethylamino) tin

The authors present a new method for preparing thin films of SnO2 by atomic layer deposition (ALD) using alternating exposures to tetrakis(dimethylamino) tin and hydrogen peroxide. This method avoids problems of corrosion and agglomeration associated with the halogenated compound, SnCl4. Tin oxide films were successfully deposited on a variety of substrates using deposition temperatures of 50–300°C at an average growth rate of 1.2A∕cycle. They use in situ quartz crystal microbalance and quadrupole mass spectrometry measurements to explore the mechanism for SnO2 ALD. Scanning electron microscopy of SnO2 films deposited on Si(100) show that the SnO2 films are smooth, conformal, and nearly featureless, while atomic force microscopy yields a surface roughness of only 0.84nm for a film with a thickness of 92nm. X-ray diffraction reveals that the SnO2 films are amorphous. Films deposited on glass yielded a resistivity of ∼0.3Ωcm and an optical transmission of 94% for a film thickness of 140nm. X-ray photoelectr...
Mechanical, histologic, and biochemical effects of canine rectal formalin instillation

Instillation of 4 percent formalin effectively treats radiation hemorrhagic proctitis; however, little is known regarding its side effects. PURPOSE: The study contained herein was undertaken to determine rectal compliance and collagen content, mucosal and vascular histologic changes, and kinetics of formalin absorption following instillation. METHODS: Fifteen mongrel dogs (50–60 pounds) were randomized into five experimental groups according to time elapsed from formalin treatment: control, acute, one week, two weeks, and four weeks. Formalin was instilled in 30-ml aliquots to a total volume of 400 ml. Rectal compliance (closed manometry system) was assessed pre-formalin and post-formalin at the designated time interval. Serum formalin metabolites were determined at time 0, 0.5, 1, and 3 hours. A segment of rectal wall was analyzed for collagen content, mucosal injury, and blood vessel density. RESULTS: Serum formalin levels peaked within 30 minutes, returning to normal by 3 hours. With the exception of one dog, toxic levels were not reached at any time during the study. No dogs experienced sepsis, fever, or altered gastrointestinal function. Acute and one-week dogs showed mild diffuse proctitis and mucosal slough, which healed within two weeks. Rectal compliance and collagen content were unchanged. Mucosal blood vessels decreased in number early (P=0.03). CONCLUSIONS: Instillation of 4 percent formalin in sequential aliquots of a small volume that is kept in contact for a short period of time is safe. Serum formalin levels generally do not reach toxic levels, and the slight elevation in formalin concentration that was seen returns to normal within three hours. Formalin-induced proctitis heals within two weeks, and no long-term changes in rectal compliance or collagen content were seen.
Risk-Based Model for Valuation of Performance-Specified Pavement Maintenance Contracts

Many transportation agencies have started outsourcing maintenance activities to contractors by means of performance-based contracts. These outsourcing contracts are intended to transfer performance-based risk from transportation agencies to private contractors for a premium cost. Even though such contracts provide numerous benefits to both contractual parties, there are equally many concerns with their implementation. Certainly, one of the most important concerns is how to quantify performance-based risk. This paper presents a general and flexible framework for quantifying the performance-based risk in terms of premium cost for different contract specifications and preventive maintenance and rehabilitation strategies. The framework developed consists of three modular components: (1) the reliability-based pavement performance model; (2) the preventive maintenance and rehabilitation models; and (3) the pricing model. The developed framework is illustrated using the current design and rehabilitation methods for flexible pavements.
Interest group incentives for post-lottery trade restrictions

The rights to use publicly-managed natural resources are sometimes distributed by lottery, and typically these rights are nontransferable. Prohibition of post-lottery permit transfers discourages applicants from entering the lottery solely for profitable permit sale, so only those who personally value the use of the resource apply. However, because permits are distributed randomly and trade is restricted, permits may not be used by those who value them most. We argue that restrictions on permit transfers is a policy response designed to limit entry when interest group membership is not distinguishable ex ante, and characterize the economic/informational conditions under which post-lottery prohibitions on trade are likely to arise. We develop our model using the specific case of the Four Rivers Lottery used to allocate rafting permits on four river sections in Idaho.
Car ‐ body construction and assembly

More than half of the industrial robots throughout the world are used in the automobile industry. The following deals with the most important application so far, spot welding in car‐body construction, and one with a promising future, namely, assembly.
Mammographic detection of early breast cancer

Abstract The concept of early breast cancer as a palpable mass with limited secondary manifestations is changing rapidly. Thanks largely to mammography, a malignant breast neoplasm can be detected long before it forms a mass. Because cure rates in this stage are high, reliable means of early detection and diagnosis are of deep concern. Early detection certainly has been the major influence in reducing mortality from carcinoma of the uterine cervix, and results of recent studies indicate that this also will be true for cancer of the breast.
Noise reduction of video imagery through simple averaging

Examiners in the Special Photographic Unit of the Federal Bureau of Investigation Laboratory Division conduct examinations of questioned photographic evidence of all types, including surveillance imagery recorded on film and video tape. A primary type of examination includes side-by- side comparisons, in which unknown objects or people depicted in the questioned images are compared with known objects recovered from suspects or with photographs of suspects themselves. Most imagery received in the SPU for such comparisons originate from time-lapse video or film systems. In such circumstances, the delay between sequential images is so great that standard image summing and/or averaging techniques are useless as a means of improving image detail in questioned subjects or objects without also resorting to processing-intensive pattern reconstruction algorithms. Occasionally, however, the receipt of real-time video imagery will include a questioned object at rest. In such cases, it is possible to use relatively simple image averaging techniques as a means of reducing transient noise in the images, without further compromising the already-poor resolution inherent in most video surveillance images. This paper presents an example of one such case in which multiple images were averaged to reduce the transient noise to a sufficient degree to permit the positive identification of a vehicle based upon the presence of scrape marks and dents on the side of the vehicle.
Small heat shock proteins Hspb7 and Hspb12 regulate early steps of cardiac morphogenesis

Abstract Cardiac morphogenesis is a complex multi-stage process, and the molecular basis for controlling distinct steps remains poorly understood. Because gata4 encodes a key transcriptional regulator of morphogenesis, we profiled transcript changes in cardiomyocytes when Gata4 protein is depleted from developing zebrafish embryos. We discovered that gata4 regulates expression of two small heat shock genes, hspb7 and hspb12 , both of which are expressed in the embryonic heart. We show that depletion of Hspb7 or Hspb12 disrupts normal cardiac morphogenesis, at least in part due to defects in ventricular size and shape. We confirmed that gata4 interacts genetically with the hspb7 / 12 pathway, but surprisingly, we found that hspb7 also has an earlier, gata4 -independent function. Depletion perturbs Kupffer's vesicle (KV) morphology leading to a failure in establishing the left–right axis of asymmetry. Targeted depletion of Hspb7 in the yolk syncytial layer is sufficient to disrupt KV morphology and also causes an even earlier block to heart tube formation and a bifid phenotype. Recently, several genome-wide association studies found that HSPB7 SNPs are highly associated with idiopathic cardiomyopathies and heart failure. Therefore, GATA4 and HSPB7 may act alone or together to regulate morphogenesis with relevance to congenital and acquired human heart disease.