cssi/SciSciGPT-SciSciNet huggingface dataset:
The Role of Work Pressure in IT Task Groups: Identifying Theoretical Constructs

This paper introduces the study of group work pressure (GWP) in information technology (IT) task groups. We theorize that GWP arises from demands and resources in group work and that high levels of GWP inhibit group performance. To identify the constructs of a new group task demands-resources (GTD-R) model, we solicit subjects’ descriptions of factors associated with high and low pressure group work situations they have experienced. We find that GWP is composed of characteristics of the task, group, environment, and individuals in the environment. Group characteristics include expertise of the group, group history, and degree of interpersonal conflicts. Individual characteristics include task motivation, personal expertise, and positive/negative consequences. Task complexity, time pressure, and external resources available to the group complete the model tasks. The findings extend prior demands-resources research, suggesting a research model for future study and practical mechanisms for reducing undesirable effects of GWP.
Current policies and practicing surgeon perspectives on parental leave.

Abstract Background The aim of this study is to evaluate the components of current parental leave policies in surgical practice and evaluate surgeon perceptions of parental leave. Methods Practicing surgeons were recruited to complete a survey via social media outlets and e-mail. Participants were asked questions regarding existing policies and their perspectives towards parental leave. Results The survey was completed by 431 surgeons, of which 90% were female and 45% in academics. The majority (84%) of women took Conclusions There is variance in current parental leave policies regarding length and compensation. Most respondents support paid parental leave and are in favor of policies that support new parents during and after pregnancy.
The Law of the Noose: A History of Latino Lynching

I wrote this article to publicize and document the widespread, but little-known, practice of Latino lynching. I discuss the number of such cases, the locations where they took place, the transgressions that motivated them, and the periods in which they broke out. I show what rendered them largely invisible to mainstream historians and discuss current social practices that are their equivalent.
8 – Alarm Assessment

Publisher Summary This chapter elaborates various aspects of alarm assessment, which can be provided through closed-circuit television (CCTV) camera coverage of each sensor sector or by visual checks by personnel. With a CCTV alarm assessment system, authorized personnel can rapidly assess sensor alarms at remote locations and avoid unnecessarily sending guards or other responders to an area. A key principle in the design and evaluation of a physical protection system (PPS) is that detection is not complete without assessment. Primary assessment is generally provided through the use of fixed cameras and most surveillance systems use pan-tilt-zoom (PTZ) cameras. Although primary assessment cameras can provide some supplementary information, secondary assessment or surveillance PTZ cameras that have variable fields of view may provide more opportunities to gather this supporting information. The use of assessment or surveillance relates to the value of the asset and the timeliness of the response that is required. Camera layouts for interior assessment follow the same principles and guidelines as for exterior cameras. It is highly recommended that exterior cameras be mounted on stable towers and mounts so that motion or movement in the wind is avoided.
The Geography of Farmworker Health in Colorado: An Examination of Disease Clusters and Healthcare Accessibility.

Background: Known by some as the “invisible” people because of their precarious work and low social status, migratory and seasonal farmworkers (MSFW) are a critical and underappreciated component t...
Cytotoxicity of juglone and thymoquinone against pancreatic cancer cells.

Abstract Juglone and thymoquinone are cytotoxic to pancreatic cancer cells. The aim of this study was to investigate, using an analysis of isobolograms, the type and degree of interactions between juglone and thymoquinone on MIA PaCa-2 pancreatic cancer cells. Cell viability was evaluated using the MTT assay. Cell death was determined by flow cytometry. The IC50 value for juglone and TQ in combination was found to be 24.75 μM, which was higher than juglone or TQ alone. Juglone alone killed Mia Paca-2 cells by ferroptosis. At concentrations where 10, 20 or 50% of cells were affected, there existed a moderate antagonistic relationship between juglone and TQ as indicated by the combination index (CI) value determined by the Compusyn software. At concentrations that affected 75% and 90% of cells, there were nearly an additive effect with CI value of 1.09249 and 0.92391, respectively. Moderate synergism was only seen at concentration where 95% of cells were affected, and the corresponding concentration of juglone and TQ at that combination was 40.90 μM and 511.19 μM, respectively.
Building Mount Sinai’s Institute for Advanced Medicine: A Value-Based Care Model for Medically Complex Populations

An end to the spread of HIV is in sight, but managing the long-term care of medically complex populations remains a challenge requiring a substantial investment in value-based care and a commitment...
Left axillary intra-aortic balloon pump prolapsing in the ascending aorta in an end-stage heart failure patient awaiting transplant

Patients with end-stage heart failure with reduced ejection fraction requiring mechanical support while awaiting heart transplant present a clinical dilemma. Intra-aortic balloon pump (IABPs) provide a modest improvement in hemodynamics and are easy to implant. Left axillary IABP implantation allows patients to engage in daily physical activity pre-transplant. We present a case of a patient awaiting heart transplant with a left axillary IABP that prolapsed above the aortic valve in the ascending aortic root requiring immediate removal. We describe our multi-modal imaging evaluation, and technique to safely remove the IABP and replace a new one into the same left axillary access while preserving vascular access.
Behavioral Health Services with Short-Stay Residents in Skilled Nursing Facilities: A Qualitative Study of Clinicians and Administrators.

Objectives: The perspectives of professionals involved in behavioral health (BH) services with short-stay residents in skilled nursing facilities (SNFs) are rarely captured in the literature. This ...
Lunadrone: Experimental UAS Designed for Lunar Operations

Unmanned Aerial Systems have drastically changed many aspects of society on Earth for the better. It is fair to assume that soon, these devices will be seen as a necessity in the process of exploring other worlds. Technologies currently exist that enable experimentation even on the most stringent of budgets. As planning begins on lunar colonies, the need for a UAS specifically designed for the lunar environment becomes increasingly apparent. The goal of the Lunadrone Experiment is to develop a pathfinding prototype that meets the specific environmental conditions expected on the moon. Technologies that were once considered proprietary and available solely to government entities are now available to consumers at reasonable price points. For this reason, the future of lunar exploration will be in the hands of private industry, where the bottom line will be far more relevant than ever before. Aiding with dangerous, dirty, or dull operations will add a further layer of protection for astronauts as well as a platform from which to collect all varieties of scientific data.
Comparisons of Planetary Boundary Layer Height from Ceilometer with ARM Radiosonde Data

Abstract. Ceilometer measurements of aerosol backscatter profiles have been widely used to provide continuous PBLHT estimations. To investigate the robustness of ceilometer-estimated PBLHT under different atmospheric conditions, we compared ceilometer- and radiosonde-estimated PBLHTs using long term U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) ceilometer and balloon-borne sounding data at three ARM fixed-location atmospheric observatories and from three ARM mobile observatories deployed around the world for various field campaigns, which cover from Tropics to Polar regions and over both ocean and land surfaces. Statistical comparisons of ceilometer-estimated PBLHTs from the Vaisala CL31 ceilometer data with radiosonde-estimated PBLHTs from the ARM PBLHT-SONDE Value-added Product (VAP) are performed under different atmospheric conditions including stable and unstable atmospheric boundary layer, low-level cloud-free, and cloudy conditions at these ARM observatories. Under unstable atmospheric boundary layer conditions, good comparisons are found between ceilometer- and radiosonde-estimated PBLHTs at ARM low- and mid-latitude land observatories. However, it is still challenging to obtain reliable PBLHT estimations over ocean surfaces even using radiosonde data. Under stable atmospheric boundary layer conditions, ceilometer- and radiosonde-estimated PBLHTs have weak correlations. Among different PBLHT estimations utilizing the Heffter, the Liu-Liang, and the bulk Richardson number methods in the ARM PBLHT-SONDE VAP, ceilometer-estimated PBLHTs have better comparisons with the Liu-Liang method under unstable and with the bulk Richardson number method under stable atmospheric boundary layer conditions.
A one-variable map analysis of bursting in the Belousov-Zhabotinskii reaction

We consider a three-variable model for the Belousov-Zhabotinskii reaction run in a continuous flow stirred tank reactor (CSTR). We focus on the complex oscillation (burst) patterns for relatively low flow rates. From the chemical model we derive a one-variable discontinuous mapping for the concentration of a critical species from one spike to the next. We consider a reasonable piecewise linear approximation to the map whose solution behavior is described analytically. Various features (e.g. bistability) of the map solutions predict burst patterns for the continuous model.
A Taxonomy of Data Managements Via Broadcasting in Mobile Computing

Data management for distributed computing has spawned a variety of research work and commercial products. At the same time, recent technical advances in the development of portable computing devices and the rapidly expanding cordless technologies have made the mobile computing a reality. In conjunction with the existing computing infrastructure, data management for mobile computing gives rise to significant challenges and performance opportunities. Most mobile technologies physically support broadcast to all mobile users inside a cell. In mobile client-server models, a server can take advantage of this characteristics to broadcast information to all mobile clients in its cell. This fact introduces new mechanisms of data management which are different from the traditional algorithms proposed for distributed database systems. In this chapter, we give executive summary and discuss topics such as data dissemination techniques, transaction models and caching strategies that utilize broadcasting medium for data management. There is a wide range of options for the design of model and algorithms for mobile client-server database systems. We present taxonomies that categorize algorithms proposed under each topic. Those taxonomies provide insights into the tradeoffs inherent in each field of data management in mobile computing environments.
Risk Aversion and Self-Insurance-cum-Protection

Self-insurance and self-protection have been discussed separately in the literature. However, as observed in practice, many actions individuals take to modify a potential loss serve both as self-insurance and as self-protection. Given this practical importance of self-insurance-cum-protection activities, this paper examines the effect of increased risk aversion on such activities. The analysis shows that the effect depends in part on the shape of the loss function and that of the probability function.
Binge/purge thoughts in nonsuicidal self-injurious adolescents: an ecological momentary analysis.

OBJECTIVE: Adolescents who self-injure often engage in bingeing/purging (BP). Ecological momentary assessment (EMA) has potential to offer insight into the relationship between self-injury and BP. The aims of this study were to examine the frequency and context of BP using EMA in a sample of nonsuicidal self-injurious (NSSI) adolescents. METHOD: Thirty adolescents with a history of NSSI responded to questions regarding self-destructive thoughts/behaviors using a palm-pilot device. Descriptive analyses compared thought/behavior contexts during reports of BP and NSSI thoughts/behaviors (occurring together vs. individually). RESULTS: BP thoughts were present in 22 (73%) participants, occurring on 32% of the person-days recorded; 59% of these participants actually engaged in BP behavior. Seventy-nine percent of BP thoughts co-occurred with other self-destructive thoughts. Adolescents were more often with friends/peers than alone or with family when having BP thoughts. Worry and pressure precipitated both BP and NSSI thoughts, but perceived criticism and feelings of rejection/hurt were associated more often with BP thoughts than with NSSI thoughts. DISCUSSION: BP thoughts and behaviors were common in this sample, often occurring with other self-destructive thoughts. Future EMA research is needed to address the function of BP symptoms, the contextual variables that increase risk for BP thoughts, and the factors that predict the transition of thoughts into behaviors in adolescents with and without self-injury. © 2013 Wiley Periodicals, Inc. (Int J Eat Disord 2013). Language: en
Phagocytosis, a Potential Mechanism for Myeloid-Derived Suppressor Cell Regulation of CD8+ T Cell Function Mediated through Programmed Cell Death-1 and Programmed Cell Death-1 Ligand Interaction

CD8(+) T cells become exhausted, inducing cell surface protein programmed cell death-1 (PD-1) as chronic virus diseases or tumors progress, but underlying mechanisms of this are unclear. We previously showed that M-CSF is important for developing tolerogenic dendritic cells (DCs) from human CD14(+) monocytes. In this article, we identify M-CSF-derived DCs (M-DCs) after stimulation with IL-10 as myeloid-derived suppressor cells with additional tolerogenic activities to CD8(+) T cells. IL-10 increased PD-1 ligand expression on M-DC, and IL-10-stimulated M-DCs (M-DC/IL-10) induced expression of PD-1 on, and apoptosis of, CD8(+) T cells and phagocytosed CD8(+) T cells. Enhanced phagocytic activity of M-DC/IL-10 required IFN-γ, which further increased PD-1 ligand and PD-2 ligand expression on M-DC/IL-10. IFN-γ-stimulated M-DC/IL-10 cells were phenotypically macrophage-like cells with little or no expression of CD86, a costimulatory molecule, but with high expression levels of CD14, CD200R, and CD80. No phagocytic activity was detected with GM-CSF-derived DCs. We propose that phagocytosis by IFN-γ-stimulated M-DC/IL-10 cells, which may be DCs or, alternatively, a unique subset of macrophages, may be a mechanism by which IFN-γ-producing CD8(+) T cells are tolerized after type 1 immune responses to chronic virus or tumor, and that IFN-γ links effector CD8(+) T cells to their phagocytic clearance.
An information theoretic robust sequential procedure for surface model order selection in noisy range data

Modeling of the unknown surface, a key first step in the perception of surfaces in range images using the function approximation approach, is considered. Akaike's entropy-based information criterion (AIC) is a simple but powerful tool for choosing the best fitting model among several competing models. However, the AIC presupposes a fixed data set and a normality assumption on the error's distribution. The AIC is extended to a t-distribution noise model, which more realistically represents anomalies in the data such as outliers and quantization errors. This criterion is modified to be used with a robust sequential algorithm to accommodate the variable data size resulting from fitting different models. The modified criterion is applied to real range data, and its performance is compared with that of AIC and Consistent AIC. >
Processos de (re)definição na poesia de Conceição Evaristo

A construcao de uma identidade feminina afro-brasileira e uma questao a ser observada. Mesmo na lingua falada no pais, na expressao “mulher negra”, o adjetivo negro contem um significado implicito de sujeira, melancolia, condenacao, etc. Esse fato tambem nos revela que principios de equidade nao fazem parte da rotina da mulher afro-brasileira: ela ainda efetua trabalhos com a mais baixa remuneracao; ainda que tenha concluido um curso superior, o mercado a rejeita devido a sua “aparencia”. Ainda que sejam muitas, as mulheres negras permanecem invisiveis. Mas, dessa invisibilidade, resurgem e constroem suas identidades. Neste artigo examino os processos por meio dos quais a poeta afro-brasileira Conceicao Evaristo elabora suas multiplas identidades, ou seja, como sai da invisibilidade para transformar marginalizacao em poder.
Outcome of laparoscopic antireflux surgery in patients with nonerosive reflux disease

As many as 50% of patients with gastroesophageal reflux disease (GERD) have no endoscopic evidence of esophagitis (EGD negative). Laparoscopic antireflux surgery (LARS) provides effective symptomatic and endoscopic healing in patients with erosive GERD (EGD positive). The surgical outcome of patients undergoing LARS for EGD-negative GERD has not received wide attention. The objective of this study was to compare surgical outcomes between EGD-negative and EGD-positive patients. During the period from June 1996 to September 1998, all patients undergoing LARS for persistent GERD symptoms despite medical therapy, who were EGD-negative, were invited to respond to a questionnaire regarding their clinical status before and after LARS. To perform a comparative analysis, the same questions were posed to a randomly selected equal number of EGD-positive patients who underwent surgery during the same study period. LARS was performed in 255 patients during the study period; 59 patients (23%) had EGD-negative GERD, and 148 (58%) were EGD-positive. Forty-eight patients (19%) did not meet the entry criteria and were excluded from analysis. LARS provided effective symptomatic relief in patients with EGD-negative and EGD-positive GERD. There were no significant differences in patient satisfaction or symptom improvement between the two groups (P = 0.82). The surgical outcome of EGD-negative patients is similar to the outcome for patients with erosive esophagitis. LARS is a valuable treatment option for patients with persistent GERD symptoms regardless of the endoscopic appearance of the esophageal mucosa.
Evidence that the F2-isoprostane, 8-epi-prostaglandin F2α, is formed in vivo

Abstract F 2 -isoprostanes are prostaglandin (PG)F 2 -like compounds that are produced in vivo as non-enzymatic products of free radical catalyzed peroxidation of arachidonic acid. One F 2 -isoprostane whose formation should be favored is 8-epi-PGF 2α . 8-Epi-PGF 2α has been shown to exert potent bioactivity but proof that it is formed in vivo is lacking. Evidence is now presented suggesting that 8-epi-PGF 2α is, in fact, formed in vivo by demonstrating that an endogenous F 2 -isoprostane with a retention time on capillary GC identical with that of 8-epi-PGF 2α co-chromatographs through four high resolving HPLC purification procedures with authentic radiolabelled 8-epi-PGF 2α .
Shaking stack model of ion conduction through the Ca(2+)-activated K+ channel

Motivated by the results of Neyton and Miller (1988. J. Gen. Physiol. 92:549–586), suggesting that the Ca(2+)-activated K+ channel has four high affinity ion binding sites, we propose a physically attractive variant of the single-vacancy conduction mechanism for this channel. Simple analytical expressions for conductance, current, flux ratio exponent, and reversal potential under bi-ionic conditions are found. A set of conductance data are analyzed to determine a realistic range of parameter values. Using these, we find qualitative agreement with a variety of experimental results previously reported in the literature. The exquisite selectivity of the Ca(2+)-activated K+ channel may be explained as a consequence of the concerted motion of the "stack" in the proposed mechanism.
On the Control of Stochastic Systems

ABSTRACT The problem of the optimal feedback control of a class of linear stochastic systems with quadratic performance measure is studied. Employing an analogue of the Pontryagin maximum principle, a set of ordinary differential equations are derived for the gain parameters of the controller. It is shown that these equations exhibit an elemental form of adaptivity. By means of an example, the applicability of the certainty equivalence principle to problems of this type is investigated.
The reaction of monomeric and aggregated immunoglobulins with Cl

Abstract The relative capacity of different immunoglobulin classes and subclasses in different states of aggregation to bind the first component of complement (C l ) was studied. Both monomeric γG and 7S γM immunoglobulins were found to be able to bind C l . The binding capacity of γG myeloma proteins was dependent upon the γG subclass, the order of reactivity being γ G3 > γ Gl > γ G2 > γ G4. No differentiation into functional subclasses was possible on the examination of 12 different monomeric γM preparations. The relative C l binding capacity of γM polymers was: 7S γ M = 1, 19S γ M = 15, 27–35S γ M = 64, and > 35S γ M = 116. Comparable amounts of the 7S subunit of γM and γG bound C l to a similar extent, and aggregated γM and γG were also comparable in C l binding, suggesting that the differences in the relative C l binding capacity of these immunoglobulins is dependent upon the degree of polymerization that is present in the native state of these proteins. The Fc fragment of γCl was as efficient as the intact protein in fixing C l , when compared on a molar basis; human F(ab′) 2 and the cyanogen bromide treated Fc fragment were unable to bind C l .
The role of adjuvant chemoradiation in the treatment of pancreatic cancer

The high rates of mortality due to pancreatic cancer have shown minimal improvement over the past few decades. Even in the most favorable subset of patients, those who are able to receive a pancreatoduodenectomy, outcomes are poor. In addition to high rates of distant metastases, pancreatic cancer is locally aggressive, with high recurrence rates post-resection. The role of adjuvant treatment using chemoradiation has been shown to improve local control and survival in pancreatic cancer, but its role remains unclear compared with chemotherapy alone given the high rates of distant failure. This review will present the historically important trials utilizing adjuvant chemoradiation, discuss more contemporary studies, and outline the future direction and results of more recent reports utilizing novel chemotherapeutic agents and advanced radiotherapy techniques in the adjuvant setting.
Kinetic analyses of liver phosphatidylcholine and phosphatidylethanolamine biosynthesis using 13C NMR spectroscopy

Choline and ethanolamine are substrates for de novo synthesis of phosphatidylcholine (PtdC) and phosphatidylethanolamine (PtdE) through the CDP-choline and CDP-ethanolamine pathways. In liver, PtdE can also be converted to PtdC by PtdE N-methyltransferase (PEMT). We investigated these kinetics in rat liver during a 60 min infusion with (13)C-labeled choline and ethanolamine. NMR analyses of liver extracts provided concentrations and (13)C enrichments of phosphocholine (Pcho), phosphoethanolamine (Peth), PtdC, and PtdE. Kinetic models showed that the de novo and PEMT pathways are 'channeled' processes. The intermediary metabolites directly derived from exogenous choline and ethanolamine do not completely mix with the intracellular pools, but are preferentially used for phospholipid synthesis. Of the newly synthesized PtdC, about 70% was derived de novo and 30% was by PEMT. PtdC and PtdE de novo syntheses displayed different kinetics. A simple model assuming constant fluxes yielded a modest fit to the data; allowing upregulated fluxes significantly improved the fit. The ethanolamine-to-Peth flux exceeded choline-to-Pcho, and the rate of PtdE synthesis (1.04 micromol/h/g liver) was 2-3 times greater than that of PtdC de novo synthesis. The metabolic pathway information provided by these studies makes the NMR method superior to earlier radioisotope studies.
Validation of a streamlined multiclass, multiresidue method for determination of veterinary drug residues in bovine muscle by liquid chromatography–tandem mass spectrometry

Multiclass, multiresidue methods are becoming increasingly popular in regulatory monitoring programs due to their increased analytical scope and laboratory efficiency. In this work, we report the development and validation of a new high-throughput analytical method to monitor up to 131 veterinary drug residues, representing at least 13 different classes, in bovine muscle. This novel method streamlined sample preparation to 11,400 analyte results for spiked samples, the rate of false negatives for identification purposes was <5%, and no false positives occurred at appreciable concentrations.
An integrated genome-wide association analysis on rheumatoid arthritis data.

We propose a nonparametric association analysis combining both family and unrelated case-control genotype data. Under the assumption of Hardy-Weinberg equilibrium, we formed an affected group to compare with a group of unaffecteds.
The structure of leptosphaerin

Abstract The structure and relative configuration of leptosphaerin, a metabolite of the marine ascomycete Leptosphaeria oraemaris (Linder) was established as 2 by spectral analysis and elimination of an alternative structure 1 through synthesis.
Association of Hemoglobin Type with Resistance to Marek’s Disease

Abstract SINCE the classical work of Pauling et al. (1949) showing that a mutant hemoglobin in humans was associated with resistance to malaria infection, attempts have been made to isolate mutant hemoglobins in other species. Once these mutant hemoglobins are isolated in a commercially important species it becomes of primary importance to determine if the mutant hemoglobin is associated with an economically important trait. A mutant hemoglobin in the Athens-Canadian randombred population of chickens changes the electrophoretic properties of the minor hemoglobin component resulting in a more rapid electrophoretic migration (Washburn, 1968a). There was no lethality associated with the mutant hemoglobin gene which was characterized as autosomal and co-dominant. Marek’s Disease (M.D.) continues to be a multimillion dollar problem in the poultry industry despite research efforts for control or eradication methods. Controlled exposure to the M.D .-agent can result in the rapid differentiation of M.D.-resistant and M.D.-susceptible lines (Cole, 1968). The…
Cost-effectiveness of "golden mustard" for treating vitamin A deficiency in India.

Background Vitamin A deficiency (VAD) is an important nutritional problem in India, resulting in an increased risk of severe morbidity and mortality. Periodic, high-dose vitamin A supplementation is the WHO-recommended method to prevent VAD, since a single dose can compensate for reduced dietary intake or increased need over a period of several months. However, in India only 34 percent of targeted children currently receive the two doses per year, and new strategies are urgently needed. Methodology Recent advancements in biotechnology permit alternative strategies for increasing the vitamin A content of common foods. Mustard (Brassica juncea), which is consumed widely in the form of oil by VAD populations, can be genetically modified to express high levels of beta-carotene, a precursor to vitamin A. Using estimates for consumption, we compare predicted costs and benefits of genetically modified (GM) fortification of mustard seed with high-dose vitamin A supplementation and industrial fortification of mustard oil during processing to alleviate VAD by calculating the avertable health burden in terms of disability-adjusted life years (DALY). Principal Findings We found that all three interventions potentially avert significant numbers of DALYs and deaths. Expanding vitamin A supplementation to all areas was the least costly intervention, at $23–$50 per DALY averted and $1,000–$6,100 per death averted, though cost-effectiveness varied with prevailing health subcenter coverage. GM fortification could avert 5 million–6 million more DALYs and 8,000–46,000 more deaths, mainly because it would benefit the entire population and not just children. However, the costs associated with GM fortification were nearly five times those of supplementation. Industrial fortification was dominated by both GM fortification and supplementation. The cost-effectiveness ratio of each intervention decreased with the prevalence of VAD and was sensitive to the efficacy rate of averted mortality. Conclusions Although supplementation is the least costly intervention, our findings also indicate that GM fortification could reduce the VAD disease burden to a substantially greater degree because of its wider reach. Given the difficulties in expanding supplementation to areas without health subcenters, GM fortification of mustard seed is an attractive alternative, and further exploration of this technology is warranted.
Transmission electron microscopy of the "LOW-CA" hydrated interplanetary dust particle

Transmission electron microscopy of a hydrated interplanetary dust particle indicates that it consists largely of a poorly crystalline phyllosilicate containing Fe, Mg and Al with an interlayer spacing of 10 to 12 A and so is distinct from the major phyllosilicate in CI and CM carbonaceous chondrites. The silicate is probably an Fe- and Mg-rich smectite or mica. Submicron, spherical to euhedral pyrrhotite and pentlandite are prominent. Unusual, low-Ni pentlandite is also common and typically occurs as rectangular platelets. Unlike many chondritic interplanetary dust particles, olivine is rare and pyroxene was not observed. Other less abundant phases are magnetite, chromite, and an unidentified phase containing Fe, Mg, Si, Ca, and Mn. This particle differs from a hydrated micrometeorite described previously by Brownlee (1978), indicating there are mineralogically different subsets of hydrated interplanetary dust particles. Despite gross similarities in mineralogy between the particle and the carbonaceous chondrites, they show appreciable differences in detail.
The yielding of truncated solid cones under quasi-static and dynamic loading

Abstract The plastic yielding of truncated solid cones has been investigated experimentally under quasistatic and dynamic axial loads at strain rates of 10 −5 sec −1 and 10 2 sec t1 , respectively. The quasistatic experiments were performed both with and without friction at the interface between the truncated end of the cone and the ‘ rigid ’ wall. Both the dynamic and the quasi-static yield stresses increase linearly with an increase in conical angle, and the dynamic values are about 20–80 per cent higher than the frictional quasi-static results. A part of this increase is due to Coulomb friction. The quasi-static experimental results are compared with lower bound axisymmetric plasticity solutions, with favourable agreement. The coefficient of friction is determined by comparing the theoretical results with the experimental results. The condition for sticking at the interface is also given. The velocity fields associated with the stress fields were considered and it was found that the Haar-von Karman hypothesis is violated in limited regions for a certain range of conical angles.
Experiments with a tree-search method for converting noisy phonetic representation into standard orthography

A tree-search algorithm was utilized in decoding the noisy phonetic output of an acoustic processor (AP) for purposes of automatic recognition of continuous speech. A 250-word lexicon and a finite-state grammar specify the tree to be searched. The search is performed in a best-first manner where partial paths having the highest similarity measure are extended first. The similarity measure of a word represents the degree of match of the noisy input with the best-fitting phonetic variant of that word. Phonetic variants for each word are generated automatically by a set of phonological rules. Computation of the similarity measure is based on statistics characterizing the performance of the AP. These statistics were obtained from training data by an iterative procedure. Performance results are given for both training and test data. Substantial improvement over earlier performance on the same data was realized.
Hermite–gaussian functions of complex argument as optical-beam eigenfunctions

Optical-resonator modes and optical-beam-propagation problems have been conventionally analyzed using as the basis set the hermite–gaussian eigenfunctions ψn (x,z) consisting of a hermite polynomial of real argument Hn [√2x/w(z)] times the complex gaussian function exp [−jkx2/2q(z)], in which q(z) is a complex quantity. This note shows that an alternative and in some ways more-elegant set of eigensolutions to the same basic wave equation is a hermite-gaussian set ψˆn(x,z) of the form Hn[√cx]exp [−cx2], in which the hermite polynomial and the gaussian function now have the same complex argument √cx ≡ (jk/2q)1/2x. The conventional functions ψn are orthogonal in x in the usual fashion. The new eigenfunctions ψˆn, however, are not solutions of a hermitian operator in x and hence form a biorthogonal set with a conjugate set of functions ϕˆn(√cx). The new eigenfunctions ψˆn are not by themselves eigenfunctions of conventional spherical-mirror optical resonators, because the wave fronts of the ψˆn functions are not spherical for n > 1. However, they may still be useful as a basis set for other optical resonator and beam-propagation problems.
Semistability of Artin and Coxeter Groups

Abstract Semistability at infinity is a geometric invariant for finitely presented groups. If G is a finitely presented group then the Semistability of G can give information about the fundamental group at infinity for G , the cohomology of G , and the shape of the boundary of G . In [6], M. Davis exhibits Coxeter groups with somewhat pathological behavior at infinity. Our main theorems are that all Artin and all Coxeter groups are semistable at infinity.
Nitric oxide is less effective at inhibiting neointimal hyperplasia in spontaneously hypertensive rats

Exogenous administration of nitric oxide (NO) markedly decreases neointimal hyperplasia following arterial injury in several animal models. However, the effect of NO on neointimal hyperplasia in hypertension remains unknown. Here, we employ the spontaneously hypertensive rat (SHR) strain, inbred from Wistar Kyoto (WKY) rats, and the carotid artery balloon injury model to assess the effects of NO on neointimal hyperplasia development. 2weeks after arterial injury, we showed that both rat strains developed similar levels of neointimal hyperplasia, but local administration of NO was less effective at inhibiting neointimal hyperplasia in the SHR compared to WKY rats (58% vs. 79%, P<0.001). Interestingly, local administration of NO did not affect systemic blood pressure in either rat strain. Compared to WKY, the SHR displayed more proliferation in the media and adventitia following balloon injury, as measured by BrdU incorporation. The SHR also showed more inflammation in the adventitia after injury, as well as more vasa vasorum, than WKY rats. NO treatment reduced the vasa vasorum in the SHR but not WKY rats. Finally, while NO decreased both injury-induced proliferation and inflammation in the SHR, it did not return these parameters to levels seen in WKY rats. We conclude that NO is less effective at inhibiting neointimal hyperplasia in the SHR than WKY rats. This may be due to increased scavenging of NO in the SHR, leading to diminished bioavailability of NO. These data will help to develop novel NO-based therapies that will be equally effective in both normotensive and hypertensive patient populations.
Clinical Application of Angiocardiography

SUMMARY The clinical value of angiocardiography for the demonstration of anomalies and the differential diagnosis between vascular and nonvascular mediastinal lesions is presented. Three congenital anomalies are presented through the courtesy of Dr. A. Castellanos. Five case histories are presented illustrating, (1) an aneurysm of the arch of the aorta; (2) a localized segmental dilatation in the descending aorta; (3) an aneurysm of the innominate or left carotid artery; (4) a nonvascular lesion; and (5) following surgery for coarctation of the aorta. 667 Madison Avenue.
AN INDO STUDY OF THE ISOMERIZATION OF AZIRIDINONE

The only pathway postulated in the literature for the isomerization of aziridinone (Ia) to iminooxirane (IIIa) involves a planar, open-chain, dipolar intermediate (IIa); however, INDO calculations suggest a possible alternative pathway in which an in-plane bending of the oxygen atom towards the alkyl carbon atom occurs rather than a stretching of the alkyl-nitrogen bond. INDO calculations also suggest that the unknown compound IIIa has the same degree of stability as Ia.
Doppler-free two-photon spectroscopy using degenerate four-wave mixing

Abstract Using recently developed techniques of degenerate, four-wave mixing, Doppler-free two-photon spectra can be obtained. The signal level for such an experiment in xenon is calculated and found to be readily detectable as well as competing favorably with the method of observing fluoresence following two-photon absorption.
Tidal salt marsh sediment in California, USA. Part 2: Occurrence and anthropogenic input of trace metals

Abstract Surface sediment samples (0–5 cm) from 5 tidal salt marshes along the coast in California, USA were analyzed to investigate the occurrence and anthropogenic input of trace metals. Among study areas, Stege Marsh located in the central San Francisco Bay was the most contaminated marsh. Concentrations of metals in Stege Marsh sediments were higher than San Francisco Bay ambient levels. Zinc (55.3–744 μg g−1) was the most abundant trace metal and was followed by lead (26.6–273 μg g−1). Aluminum normalized enrichment factors revealed that lead was the most anthropogenically impacted metal in all marshes. Enrichment factors of lead in Stege Marsh ranged from 8 to 49 (median = 16). Sediments from reference marshes also had high enrichment factors (2–8) for lead, indicating that lead contamination is ubiquitous, possibly due to continuous input from atmospherically transported lead that was previously used as a gasoline additive. Copper, silver, and zinc in Stege Marsh were also enriched by anthropogenic input. Though nickel concentrations in Stege Marsh and reference marshes exceeded sediment quality guidelines, enrichment factors indicated nickel from anthropogenic input was negligible. Presence of nickel-rich source rock such as serpentinite in the San Francisco Bay watershed can explain high levels of nickel in this area. Coefficients of variation were significantly different between anthropogenically impacted and non-impacted metals and might be used as a less conservative indicator for anthropogenic input of metals when enrichment factors are not available.
Fed-batch with biomass recycle and batch production of 2,3-butanediol from glucose by Bacillus polymyxa

The production of 2,3-butanediol from glucose by Bacillus polymyxa in batch was sensitive to both protein concentration and aeration rate. Two fed-batch experiments which were resupplied from a reservoir containing urea as the sole source of nitrogen, and incorporated total biomass recycle resulted in yields of 65.84 mM and 69.66 mM of 2,3-butanediol per 100 mM of glucose utilized. No massive sporulation events were detected. In addition, fed-batch with recycle yielded more butanediol and less acetate than any batch run.
Transit Paradise Lost: What Transit Agency Administrators Say Hinders Them From Pursuing Social Justice and Fairness

Among the ways the pursuit of social justice by transit administrators can be thwarted are a lack of support by local elected and unelected leaders; funding mechanisms and budget reductions, which prevent the transit agency from fully achieving its objectives; and zoning and development decisions, which take urban development continually farther from the dense, transit-friendly urban core and frustrate the ability of transit providers to reach spread-out destinations. Although such intentional or negligent obstructions can have a chilling effect on transit service provision and pursuit of social justice concerns, other actions, such as an outright refusal to allow a transit agency to operate, perpetuate the injustices of a stratified society, evidence a disregard of transportation equity by local leaders, and constitute the social oppression some transportation scholars decry. By interviewing 30 transit administrations across the United States, this article will consider how transit agency administrators report their pursuit of social justice agendas is hindered by local political or societal obstacles.
Rapid thermal annealing of MIS GaAs schottky barriers

It is found that rapid thermal annealing of thin oxide/GaAs increases the barrier height of contacts made on these surfaces. The increase of barrier height is related to charge introduced to the oxide layer. The reverse current increases for annealing temperatures higher than 600 °C. On a decouvert que le recuit thermal rapide des oxides/GaAs peu epais augmente la hauteur limite (barrier height) des contacts faits sur ces surfaces. L'augmentation de la hauteur limite est apparente a la charge imposee a cette couche d'oxide. Le courant inverse augments quand la temperature du recuit monte au dela de 600 °C.
Ocular vascular hamartomas: the relationship with phakomatoses and possible commonalities in pathogenesis.

Abstract Background Ocular vascular hamartomas may present as isolated lesions or as part of a multisystemic congenital syndrome known as vascular phakomatoses . These syndromes are characterized by ocular, cerebral, and cutaneous lesions. Although each of these lesions manifests distinct characteristics, there may be overlapping characteristics and manifestations attributable to a common pathogenesis. Methods A case series and a literature review are presented illustrating ocular and systemic manifestations associated with vascular hamartomas, with each case representing varying degrees of ocular and systemic expression. Conclusion Because of the potential ocular morbidity and systemic mortality associated with vascular hamartomas and associated syndromes, the optometrist plays an important role in the management of these patients. In general, understanding the pathogenesis of these diseases may contribute to future treatment and prevention opportunities.
Glass Armor – An Overview

Transparent armor for military vehicles has recently gained renewed attention. However the ballistic impact and penetration processes of glass armors are not well understood. Different types of glasses exhibit different ballistic responses, and a pressing need exists to better comprehend and model these responses in order to develop lightweight armors. The need to better understand the processes of densification and dynamic fracture and the need for input and validation data for continuum models are highlighted as examples.
7 Relation of functional ovarian hyperandrogenism to non-insulin dependent diabetes mellitus

Up to 40% of women with polycystic ovary syndrome (PCOS) demonstrate some degree of glucose intolerance, either impaired glucose tolerance (IGT) or non-insulin dependent diabetes mellitus (NIDDM). Defects in insulin action have long-been recognized as characteristic in these women. Recently, evidence has been obtained which documents that insulin secretory dysfunction also contributes significantly to the observed glucose intolerance. This chapter will focus on the recent evidence supporting the specific roles of disordered insulin secretion and action, in the development of glucose intolerance in PCOS. In addition, the use of pharmacological agents that modify insulin action as therapeutic options for women with PCOS, will be discussed.
Signal Processing on Waveform Data from the Eyesafe Ladar Testbed (ELT)

The Eyesafe Ladar Test-bed (ELT) is a raster scanning, single-beam, energy-detection ladar with the capability of digitizing and recording the return pulse waveform at 2 GHz in the field for off-line 3D point cloud formation research in the laboratory. The ELT serves as a prime tool in understanding the behavior of ladar waveforms. Signal processing techniques have been applied to the ELT waveform in an effort to exploit the signal with respect to noise reduction, range resolution improvement, and ability to discriminate between two surfaces of similar range. This paper presents a signal processing method used on the ELT waveform. In the processing, three deconvolution techniques were investigated-the Wiener filter, Richardson-Lucy deconvolution, and a new method that synthesizes the surface response using least squares minimization. Range error and range resolution are reported for these methods.
Relation between Respiratory Sinus Arrythymia and Startle Response during Predictable and Unpredictable Threat

Research suggests that lower respiratory sinus arrhythmia (RSA) is associated with greater aversive responding. One physiological indicator of aversive responding is startle potentiation. While a few studies have demonstrated an inverse association between RSA and startle potentiation, no study to date has distinguished whether this relation is similar for predictable versus unpredictable aversive stimuli. This is an important distinction, given that degree of predictability has been shown to be an important determinant of aversive responding. The present study examined whether resting RSA was associated with startle eye blink responding during predictable and unpredictable threat of electric shock. Resting RSA was collected during a 6-min seated baseline phase at the beginning of the experimental session. Participants then completed a computerized startle task in which predictable and unpredictable shocks were administered. Results indicated that lower resting RSA was associated with greater startle pote...