cssi/SciSciGPT-SciSciNet huggingface dataset:
Predictors of mortality in minority patients admitted to the ICU with COVID-19 infection

INTRODUCTION:Coronavirus-2 disease 2019 (COVID-19) is a novelty virus that caused a worldwide pandemic. It can cause mild to critical illness requiring intensive care unit (ICU) admission. In the United States, Black and Hispanic individuals comprise a disproportionately high number of infections and deaths due to COVID-19, likely related to underlying social and healthcare disparities.1,2 There are limited studies identifying predictors of outcome among COVID-19,3 in minority patients. The aim of this study was to identify the predictors of mortality among laboratory confirmed COVID-19 minority patients with severe clinical disease admitted to the ICU. METHODS:Clinical data at the time of ICU admission was extracted from electronic records for a total of 95 sequentially admitted patients to the medical ICU with confirmed COVID-19 diagnoses. Demographics, comorbidities, laboratory values that included inflammatory markers, ICU course, mortality and discharge status data were collected. The primary outcome was ICU mortality treated as a binary outcome. Summary characteristics were described based on survival status with a test of significance using ANOVA, kwallis and chisquare as appropriate. A univariate logistic regression was used to identify mortality predictor variables of statistical significance which were then included in a final multivariate regression model. Inflammatory markers were added individually to this finalized model to avoid collinearity. Findings were summarized using odds ratios and confidence intervals. RESULTS:The mean (SD) age was 61.54(14) years, 34(36%) were men, 67(71%) were African Americans and 20 (16%) were Hispanic. Most common comorbidities were hypertension 55 (58%) and diabetes 46 (48%). Fifty-three (56%) were intubated, 23 (25%) required pressor support, and 15 (16%) patients had their initial blood culture positive. Inflammatory markers were elevated in most all patients which was associated with mortality. ICU mortality was 48% (45 patients). Univariate analysis identified age ≥ 65yrs (odds ratio [OR]=1.25;95% CI,1.02-1.52;p= 0.032), higher SOFA scores of 2 and 3{ (OR=1.74, 95% CI ,1.05-2.89,p=0.035) and (OR=1.90,95%CI,1.1-3.29;p=0.024 respectively)}, vasopressor use ( OR=1.77;95%CI,1.44-2.18;p 2.5ng/ml (OR=1.84;95% CI, 95%CI,1.03-3.29;p=0.042), ferritin>2000ng/ml (OR=1.45;95% CI,1.12-1.89;p=0.007), CRP>20mg/dl (OR=1.67 OR=;95CI,1.3-2.13;p 400 (OR=1.68;95%C,1.26-2.23;p<0.001) as predictors of ICU morality. Of these, only age ≥ 65yrs, mechanical ventilation and vasopressor use remained statistically significant independent predictors of mortality in multivariable regression model. CONCLUSIONAmong predominantly minority patients with severe COVID-19 admitted to the ICU, older patients who become intubated, requiring vasopressor support and/or had elevated biomarkers of inflammation had a significantly higher ICU mortality.
Non-exenterative surgical management of recurrent endometrial carcinoma.

Abstract Objective To examine the role of non-exenterative secondary cytoreductive surgery (SCS) compared with non-surgical treatments and identify predictors of improved survival for patients with recurrent endometrial cancer (EC). Methods All patients undergoing primary surgical management for EC 1/1/2009–12/31/2017 who subsequently developed recurrence were retrospectively identified. Survival was determined from date of diagnosis of first recurrence to last follow-up and estimated using Kaplan-Meier method. Differences in survival were analyzed using Log-rank and Wald tests, based on Cox Proportional Hazards model. Results Among 376 patients with recurrent EC, median time to recurrence was 14.3 months (range, 0.2–102.2), post-recurrence median survival 29 months, median follow-up 29.2 months (range, 0–116). Sixty-one patients (16.2%) received SCS, 257 (68.4%) medical management (MM) (chemotherapy and/or radiation therapy), 32 (8.5%) hormonal therapy, 26 (6.9%) no further therapy. Patients selected for SCS were younger, had more endometrioid histology, more stage I disease at initial diagnosis, no residual disease after primary surgery, longer interval to first recurrence or progression, and the longest OS (57.6 months) (95% CI, 33.3–not reached). On multivariate analysis SCS was an independent predictor of improved survival. Among the 61 SCS patients, age Conclusions While MM was the most common treatment for first recurrence of EC, patients selected for surgery demonstrated the greatest survival benefit even after controlling for tumor size, site, histology, stage, time to recurrence. Careful patient selection and favorable tumor factors likely play a major role in improved outcomes. Surgical management should be considered whenever feasible in medically eligible patients, with additional consideration given to our suggested criteria.
Cooling e-cigarette flavors and the association with e-cigarette use among a sample of high school students.

INTRODUCTION: E-liquid flavor is typically presented by flavor category (e.g. menthol, mint, fruit, dessert). Cooling sensations produced by flavor additives such as menthol enhance appeal of e-cigarettes among youth, but not all e-liquids that produce cooling sensations are labeled as menthol. Sensory experiences produced by flavors may allow for a new way to capture e-cigarette flavor use. This study aims to examine use of flavors that produce cooling sensations among youth and its association with e-cigarette use behaviors. METHODS: A 2019 survey of high school students (n = 4875) examined use of e-cigarette flavors that produced cooling sensations (cooling flavors) among past 30-day e-cigarette users. E-cigarette use behaviors (flavor use, nicotine use, frequency of use) were examined between those who did and did not use cooling flavors. A binary logistic regression was used to examine associations between vaping frequency, nicotine (vs. non-nicotine) use, and vaping cooling flavors while controlling for demographics, number of flavors vaped in the past month, and vaping age of onset. RESULTS: 51.6% (n = 473/916) of the analytic sample endorsed vaping cooling flavors. There were no demographic differences by vaping cooling flavors. Vaping cooling flavors was associated with vaping more frequently (AOR:1.04,95% CI:1.03,1.05) and vaping nicotine (AOR:2.37,95% CI:1.53,3.67). CONCLUSION: Vaping cooling flavors was associated with greater nicotine vaping and frequency of e-cigarette use. Assessing sensory experience, such as cooling, in addition to flavor category may more fully capture e-cigarette flavor use and its impacts on youth e-cigarette use behaviors.
Apparent homozygosity for a novel splicing variant in EPS8 causes congenital profound hearing loss.

Autosomal recessive deafness-102 (DFNB102), a new profound prelingual non-syndromic hearing loss, is caused by mutations in the EPS8 gene. To date, only three such consanguineous families with three different homozygous variants in EPS8 have been reported. Here, we report the fourth case from a non-consanguineous Chinese family, an 11-month-old male infant presented with congenital profound non-syndromic hearing loss. Trio whole-exome sequencing initially identified the patient with a novel seemingly homozygous splicing variant NM_004447.5: c.1435-2A > T in intron 14 of the EPS8 gene and was inherited from his father; further CNVs analysis identified a novel 65.9 kb intragenic deletion and was inherited from his mother. The deletion is covering intron 14 that could account for the apparent homozygosity of the patient. In vitro splicing assay showed the variant c.1435-2A > T creates a new donor site at position c.1443, which is predicted to produce a stop codon after 14 additional amino acids (p.His479Cysfs*14). Furthermore, quantitative allele-speciﬁc expression assay showed that relative EPS8 gene expression in the patient significantly decreased (0-fold for the wild-type transcript and 0.25-0.27-fold for the mutant transcript) compared to the control (P < 0.05), indicating the pathogenicity of the identified variants. Overall, our study provides additional evidence that EPS8 is a causative gene for DFNB102 and highlights the clinical utility of simultaneous analysis of CNVs and SNVs to avoid potential errors in the diagnosis and interpretation of patients with apparent homozygosity.
Reaction of trialkyl phosphites with aromatic aldehydes: Carboncarbon condensations from the reaction ofp-nitrobenzaldehyde and ofo-nitrobenzaldehyde with trialkyl phosphites—new routes to glycol phosphates

Abstract Trialkyl phosphites induced a carbon carbon condensation reaction in p -nitrobenzaldehyde and in o -nitrobenzaldehyde, at 20°. The products were 2,2,2- trialkoxy -4,5- di nitrophenyl )1,3,2- dioxaphospholanes . Both diastereomers at carbon were produced; the major isomer had the meso -configuration. The phospholanes were hydrolyzed to glycol phosphotriesters of known configuration. The phospholanes were converted into dinitrostilbene oxides of known configuration by hot alcohol. m -Nitrobenzaldehyde, the chlorobenzaldehydes, and aromatic aldehydes with electron-releasing groups, failed to react with trialkyl phosphites at 20°. A previous report of the course of these reactions was shown to be in error.
Technological Changes in Porcelain Enameling, 1955–2005

Significant changes have occurred the enameling industry over the last half- century. Various technical aspects and tests related to porcelain enamels are reviewed and discussed in light of today's needs.
Governance and Corruption Constraints: The Business Ethics Glass Ceiling in Middle East Corporate Governance

This paper argues for a model of a corruption constraint on organizational growth and development in the form of a business ethics glass ceiling. Although the problem of corruption‘s negative impact on economic growth is well documented, this paper‘s contribution is to propose a cohesive model to show how corruption combines with other influences such as weak corporate governance to act as a serious constraint on the business growth of local firms. This previously unidentified barrier to business success is marked by corruption and the model particularly applies to small and medium-sized and family businesses in the Middle East and North Africa (MENA). These businesses are vital to the economic growth and political stability of that region, but corruption makes it difficult for them to grow, overcome a financing gap, and become stronger organizations. Corruption also drains firm resources and warps normal incentives like transparency and accountability that encourage expansion because firms may choose to appear unprofitable to avoid corruption. As a result, the growth of these businesses is limited when they remain poorly run and small in size as they attempt to avoid an onslaught of corruption. This short-term coping strategy fosters the glass ceiling constraint that is the subject of this paper. The business ethics glass ceiling is formed by several factors. These influences are weak corporate governance, social and cultural aspects, and political and economic pressures. This paper focuses on the role of corporate governance and first describes the constraints and the place of these businesses in MENA, before using the regional example of Lebanon to demonstrate the stunting nature of the corruption-influenced ceiling and its role in producing a financing gap. Finally, the paper presents recommendations for breaking through the glass ceiling and provides suggestions for additional research on the intersection of corruption and ethics constraints in emerging markets.
Scavenger and Lead Poisoning of Automotive Oxidation Catalysts

The deactivation of noble metal oxidation catalysts of lead and halide lead scavengers was studied in engine and laboratory experiments. Lead alone or lead plus scavengers produced a persistent poisoning of the catalyst. Lead poisoning effects were increased by increased catalyst temperatures and fuel lead content. Tests with scavengers only, conducted in an engine previously operated on leaded fuel, showed that lead was transported to the catalyst causing lead poisoning even in the absence of lead in the fuel. These experiments showed that the reversible scavenger inhibition effects could be superimposed on the persistent lead poisoning effects.
The adenovirus L4 100-kilodalton protein is necessary for efficient translation of viral late mRNA species

When screening a number of adenovirus type 5 (Ad5) temperature-sensitive mutants for defects in viral gene expression, we observed that H5ts1-infected 293 cells accumulated reduced levels of newly synthesized viral late proteins. Pulse-labeling and pulse-chase experiments were used to establish that the late proteins synthesized in H5ts1-infected cells under nonpermissive conditions were as stable as those made in Ad5-infected cells. H5ts1-infected cells contained normal levels of viral late mRNAs. Because these observations implied that translation of viral mRNA species was defective in mutant virus-infected cells, the association of viral late mRNAs with polyribosomes was examined during the late phase of infection at a nonpermissive temperature. In Ad5-infected cells, the majority of the viral L2, L3, L4, pIX, and IVa2 late mRNA species were polyribosome bound. By contrast, these same mRNA species were recovered from H5ts1-infected cells in fractions nearer the top of polyribosome gradients, suggesting that initiation of translation was impaired. During the late phase of infection, neither the polyribosome association nor the translation of most viral early mRNA species was affected by the H5ts1 mutation. This lesion, mapped by marker rescue to the L4 100-kilodalton (kDa) nonstructural protein, has been identified as a single base pair substitution that replaces Ser-466 of the Ad5 100-kDa protein with Pro. A set of temperature-independent revertants of H5ts1 was isolated and characterized. Either true reversion of the H5ts1 mutation or second-site mutation of Pro-466 of the H5ts1 100-kDa protein to Thre, Leu, or His restored both temperature-independent growth and the efficient synthesis of viral late proteins. We therefore conclude that the Ad5 L4 100-kDa protein is necessary for efficient initiation of translation of viral late mRNA species during the late phase of infection.
RNA polymerase III transcription from the human U6 and adenovirus type 2 VAI promoters has different requirements for human BRF, a subunit of human TFIIIB

Mammalian TFIIIB can be separated into two fractions required for transcription of the adenovirus type 2 VAI gene, which have been designated 0.38M-TFIIIB and 0.48M-TFIIIB. While 0.48M-TFIIIB has not been characterized, 0.38M-TFIIIB corresponds to a TBP-containing complex. We describe here the purification of this complex, which consists of TBP and a closely associated polypeptide of 88 kDa, and the isolation of a cDNA corresponding to the 88-kDa polypeptide. The predicted protein sequence reveals that the 88-kDa polypeptide corresponds to a human homolog of the Saccharomyces cerevisiae BRF protein, a subunit of yeast TFIIIB. Human BRF (hBRF) probably corresponds to TFIIIB90, a protein previously cloned by Wang and Roeder (Proc. Natl. Acad. Sci. USA 92:7026-7030, 1995), although its predicted amino acid sequence differs from that reported for TFIIIB90 over a stretch of 67 amino acids as a result of frameshifts. Immunodepletion of more than 90 to 95% of the hBRF present in a transcription extract severely debilitates transcription from the tRNA-type VAI promoter but does not affect transcription from the TATA box-containing human U6 promoter, suggesting that the 0.38M-TFIIIB complex, and perhaps hBRF as well, is not required for U6 transcription.
Social isolation, vital exhaustion, and incident heart failure: findings from the Atherosclerosis Risk in Communities Study.

Aims Prospective studies have shown that social isolation (i.e. lack of social contacts) predicts incident coronary heart disease (CHD), but it is unclear whether it predicts incident heart failure (HF) and what factors might mediate this association. HF patients may be more susceptible to social isolation as they tend to be older and may have disrupted social relationships due to life course factors (e.g. retirement or bereavement). We prospectively examined whether individuals with higher vs. low social isolation have a higher incidence of HF and determined whether this association is mediated by vital exhaustion. Methods and results We estimated incident HF hospitalization or death among 14 348 participants from Visit 2 (1990–1992) in the Atherosclerosis Risk in Communities (ARIC) study using Cox proportional hazard models which were sequentially adjusted for age, race/study community, gender, current smoking, alcohol use, and co-morbidities. We conducted mediation analyses according to the Baron and Kenny method. After a median follow-up of 16.9 person-years, 1727 (13.0%) incident HF events occurred. The adjusted hazard of incident HF was greater for those in the higher vs. low social isolation risk group (hazard ratio 1.21, 95% confidence interval 1.08–1.35). Our data suggest that vital exhaustion strongly mediates the association between higher social isolation and incident HF (the percentage change in beta coefficient for higher vs. low social isolation groups after adjusting for vital exhaustion was 36%). Conclusion These data suggest that greater social isolation is an independent risk factor for incident HF, and this association appears to be strongly mediated by vital exhaustion.
Product ion charge state determination via ion/ion proton transfer reactions.

Proton transfer from protonated pyridine to product anions derived from quadrupole ion trap collisional activation of the triply charged anion of the oligonucleotide 5‘-d(AAAA)-3‘ and the 6- charge state of oxidized bovine insulin A-chain is shown to be a rapid and effective way to determine product ion charge states. The reactions are carried out in a quadrupole ion trap as part of a procedure involving three stages of mass analysis. It is demonstrated that the reactions can be driven at rates sufficiently high to convert 30−80% of the initial product anion population to second generation products in 50−200 ms. The use of ion/ion reactions enjoys significant advantages over the use of ion/molecule proton transfer chemistry. For example, ion/ion reactions are more universal than ion/molecule reactions due to their greater exothermicity, and ion/ion reactions allow for precise control over the timing of introduction and ejection of each reactant. Despite the high exothermicity of the reactions, no signific...
Evaluation and management of the patient with syncope.

Objective. —To review the studies on diagnostic evaluation of syncope and to provide an approach to the diagnostic testing and management of this condition. Data Source. —Published studies on the evaluation of syncope in the English language. Study Selection. —Cohort studies and case series of patients presenting with syncope and focused studies of various diagnostic tests such as prolonged electrocardiographic monitoring, electrophysiologic studies, and upright tilt testing. Specific selection criteria were used in the case of prolonged electrocardiographic monitoring, in which all studies had to have performed at least 12 hours of monitoring. Data Extraction. —Studies reviewed by the author. Data Synthesis. —Studies in the 1980s have shown that a cause of syncope is not diagnosed in as many as 47% of the patients presenting with this symptom. When a cause of syncope is established, a history and physical examination lead to the identification of 56% to 85% of the causes. In the remaining patients, arrhythmia detection is a central issue. A major problem with the use of ambulatory electrocardiographic (Holter) monitoring in the diagnosis of arrhythmias is that symptomatic correlation with arrhythmias is rarely found (only 4% of patients). Increasing the duration of monitoring from 24 to 72 hours does not lead to increased yield of symptomatic arrhythmias. Patient-activated intermittent loop recorders that can be worn for several weeks may occasionally show a symptomatic correlation, but they are most useful in patients with multiple recurrences of syncope. Electrophysiologic studies are more likely to be abnormal in patients with underlying heart disease or those who have abnormalities on surface electrocardiogram. The most common abnormality found on electrophysiologic studies is inducible ventricular tachycardia. Upright tilt testing has been used to induce vasovagal syncope in patients with syncope of unknown cause. A positive response has been found in 26% to 87% of patients undergoing this type of testing. The specificity of this test needs to be further investigated. In patients with recurrent syncope of unknown cause, psychiatric evaluation should also be pursued for illnesses such as generalized anxiety disorder, panic disorder, somatization, and major depression. Conclusions. —A directed approach to the evaluation is possible using the studies on diagnostic testing of syncope. ( JAMA . 1992;268:2553-2560)
Kinetic aspects of the formation of the ordered phase in stiff‐chain helical polyamino acids

The helical polyamino acids exhibit a two-component temperature-composition phase diagram that corresponds well in overall appearance to the Flory prediction for rigid, impenetrable rods. The phase diagram may be characterized as a narrow, typically 1–2%, biphasic region separating the disordered (isotropic) state from the ordered (liquid–crystalline) state, connected to a wide biphasic region in which nearly pure polymer is in equilibrium with nearly pure solvent. Initial studies have been undertaken to deduce the kinetics of formation of the ordered phase, both when the thermodynamically stable state is the ordered state, as well as when it is in an ordered-disordered biphasic state. The time course of the formation of the ordered phase at different temperatures is reminiscent of analogous studies on polymer crystallization, describable by a nucleation and growth mechanism. Formation of the ordered phase when the final state is the narow biphasic state appears also to follow a nucleation-growth mechanism. However, when the final state is the wide biphasic region, the morphology of the final state is that of an optically clear, self-supporting gel, even at very low concentrations (as low as 0.03 wt %). The reasons for and nature of the gel state are believed to be a kinetic phenomenon. The shape of the phase diagram is such that the temperature range of thermodynamic metastability is small and phase separation occurs in the thermodynamically unstable region. In the unstable region the zero activation-energy spinodal decomposition mechanism dominates the kinetics of phase separation, leading to bicontinuous interconnected phases that have little possibility or driving force to rearrange further. The polymer network structure is proposed to be a bulk thermodynamic phase, characterized by bundles or sheets of polymer between branch points, rather than individual chains as in the usual polymer network. Rheological, electron microscope, and light-scattering data are presented that support this view. The possibility of other stiff-chain polymers forming a network structure for similar reasons is discussed.
Concurrent error detection in highly structured logic arrays

Two strategies for encoding the inputs and outputs of highly structured logic arrays (HSLAs) are introduced. The two schemes are particularly relevant for concurrent error detection of both permanent and nonpermanent errors in programmable logic arrays (PLAs) and read-only memories (ROMs). The first method of concurrent error detection (CED) is based on a comprehensive fault model and relies on detection of unidirection errors. The second approach relies on a detailed examined of decoder layouts resulting in fault avoidance through layout rules, which avoid failures causing unidirectional errors. Efficient parity techniques are shown to provide a low-overhead solution to concurrent error detection when coupled with appropriate fault-avoidance techniques.
Water-mediated magnesium-guanine interactions

Divalent cations, particularly magnesium, play an important role in the stabilization of nucleic acids and in their biochemistry. Of special interest is the strong affinity of a hydrated magnesium ion for guanine. To investigate the nature of this interaction, we calculated the interaction energy (IE) for eight optimized complexes in which tetra-, penta-, and hexahydrated magnesium ions were initially placed in the plane of guanine near the O6 and N7 binding sites. Results at the RHF/6-311G**//RHF/6-311++G** level indicate that the guaninetetrahydrated magnesium ion complex has the highest value of the IE. However, the formation of the tetrahydrated magnesium ion from a hexahydrated ion decreases the energy of this complex and, overall, the hexahydrated ion is considered to be more stable. We also investigated the binding site of a hexahydrated magnesium ion located in a high-resolution crystal structure of the dodecamer [d(CGCGAATTCGCG)]2. Complexes of the hexahydrated magnesium ion with the individual and combined G2 and G22 bases extracted from the crystal structure were also considered and Natural Energy Decomposition Analysis used to partition the IEs. The results show that water-mediated charge transfer from guanine to magnesium plays an important role in the stabilization of these guanine-water-magnesium complexes and occurs by a cooperative mechanism.
Investigation of defects generated in vertically oriented graphene

Vertically oriented graphene nanosheets are promising electrode materials for electrochemical double-layer capacitors. The external surface area of the nanosheets allows for extremely fast response times compared to porous carbon materials currently used. Furthermore, the high edge density increases the charge storage ability of the material. In this paper Ar+ ions were used to create a larger density of surface defects, which were then characterized by X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy. The results indicate a change in the density of states near the Fermi level with increased defect density, which suggests a corresponding increase in electrochemical capacitance capability.
Integrated Manufacturing System for Precision Press Tooling

The press tooling industry, characterised by many small-scale job-shops, is facing an increasingly competitive global market. This comes at a time when there is a shortage of experienced process planners and unavailability of affordable CAD/CAM systems that could provide an integrated solution for manufacturing sheet metal tooling. Many commercially available CAD/CAM systems are either too expensive or too narrow in scope, in the sense that they provide only point solutions. The design of press tools and its manufacturing functions are highly specialised and knowledge-intensive in nature. This paper presents a framework and the implementation details of an integrated system that has been developed for a local sheet metal tooling company specialising in precision punches and dies. A PC-based system has been implemented on an AutoCAD platform using the Autolisp programming language.
Analysis on the seismic energy dissipation response of the 500kV metallic oxide lightning arrester

The 500kV metallic oxide lightning arrester is a piece of porcelain electrical equipment and easy to be damaged under severe earthquake, because the equipment is made of brittle materials and can only subject to limited earthquake action. Damping devices can be mounted onto the porcelain electrical equipment to protect the equipment by absorbing large amount of earthquake energy. On that type of lightning arrester added with damping devices, the analyses of the seismic energy dissipation response of the equipment are carried out at different levels of seismic fortification intensity using the finite element analysis program ANSYS. At the same time, a contrast analysis on the seismic responses of anti-seismic and seismic energy dissipation of the lightning arrester was conducted. The results of the analysis showed that the arrester with damping device had good damping effect and it could be referred by the practical application of engineering projects.
Learning a new poem : Memory for connected speech and phonological awareness in low-income children with and without specific language impairment

This research examined rote memory for connected speech in low-income children with and without specific language impairment (SLI). Sixteen children with SLI were matched to 16 typically developing...
The Morning After: Assessing the Effect of Major Terrorism Events on Prosecution Strategies and Outcomes

A major terrorism event has several important consequences for officials involved in the investigation and prosecution of terrorist activities. Such events are likely to bring increased scrutiny by both public policy officials and the media. The article uses data from the American Terrorism Study to compare the period before and after two of the most dramatic terrorist events on U.S. soil: the Oklahoma City bombing and the 9/11 attacks. The results suggest that whether intentional or not, major terrorism events result in the government's pursuing cases that are generally less serious and less complicated, and those cases are treated much more like “traditional” crimes by the prosecution. Following the aftermath of a major event, terrorist defendants are more likely to behave like traditional offenders and are less likely to be convicted as a result of a trial than are terrorists who are indicted before major events.
Effects of initial silicon carbide surface composition on room temperature Au/β-SiC(001) interface formation

Abstract Au was deposited in situ on β-SiC(001) surfaces at room temperature after the substrates were cleaned by annealing, first in a Si flux and then in vacuum. By adjusting the time and temperature of the vacuum anneal, SiC surfaces of four compositions, ranging from Si-rich to Si-deficient, were obtained. Surfaces were monitored using Auger electron, electron energy loss, X-ray photoelectron, and ultraviolet photoelectron spectroscopies as Au films ranging in thickness from ∼ 1 to 37 A were deposited. For Au on Si-terminated β-SiC surfaces, three distinct regions formed as the Au overlayer grew: interfacial Au-Si alloy, pure Au above the alloy, and a surface layer of Au-Si alloy. Interfacial alloy thickness and surface alloy Si concentration were both proportional to the amount of Si on the initial SiC surface. For Au depositions s 5 A, bands bending change, dependent on the initial β-SiC surface composition, were observed. On Si-deficient β-SiC surfaces, the Au growth mode differed completely. Au clusters formed, similar to Au behavior on C substrates. No band bending changes were observed, consistent with weak film/substrate interaction. For the Au/β-SiC system, overlayer composition and morphology are controlled by composition changes in the top 1–2 monolayers of the SiC substrate.
Recurrence relations for the Mie scattering coefficients

The Mie scattering coefficients satisfy recurrence relations:an−1, bn−1, an, and bn determine an+1, and bn+1. It is therefore possible, in principle, to generate the entire set from the first four, which has a simple interpretation. Each term in a multipole expansion of an electrostatic field can be obtained by differentiating the preceding term. The Mie coefficients are terms in a multipole expansion of a particular electromagnetic field, namely, that scattered by an arbitrary sphere. By analogy, it is not surprising that all these coefficients can be generated from the electric and magnetic dipole and quadrupole terms. Moreover, the recurrence relations for the Mie coefficients contain finite differences, in analogy with the infinitesimal differences (derivatives) in the multipole expansion of an electrostatic field.
Rapid 18O analysis of small water and CO2 samples using a continuous-flow isotope ratio mass spectrometer.

High-frequency throughput is often needed in isotopic studies in biological and medical fields. Here we report that high-precision oxygen isotope ratio measurements of water (+/-0.13 per thousand) were rapidly and routinely made on small samples (40-100 microL) using an isotope ratio mass spectrometer operated in continuous-flow mode. Simple modifications to existing instrumentation allow for rapid manual analyses of dilute CO2 (10% CO2/90% N2), including the addition of a septum port and water trap prior to the gas chromatography (GC) column (elemental analyzer column in this study) and the extension of fused-silica capillary tubing between the mass spectrometer source and the effluent tubing from the GC column (located within the CONFLO unit on Finnigan mass spectrometers). We routinely analyzed 20 small-volume samples per hour using this technique, without sacrificing precision of the oxygen isotope ratio measurement.
Functional recovery of porcine hepatocytes after hypothermic or cryogenic preservation for liver support systems

The provision of an immediate supply of isolated porcine hepatocytes for artificial liver support requires preservation techniques that will allow maintenance of cell viability and detoxification functions. By means of a simple and cost-effective cryopreservation system, porcine hepatocytes can be available for both local and distant medical treatment facilities. Additionally, cryopreservation provides an adequate period for quality control testing to be completed prior to use of any specific cell lot. We are reporting a dual approach, namely the preservation of porcine hepatocytes, at 4°C and at −196°C in liquid nitrogen (LN2). Using a combination of cryoprotectant agents with Chee's modified Eagle's culture media (CEM), collagenase isolated hepatocytes stored at 4°C for 24 h maintained 80% of the initial diazepam metabolism measured in freshly isolated cells and nearly 100% of initial function was preserved in hepatocytes stored up to 6 mo at −196°C. University of Wisconsin solution (UW) was also tested and while adequate for 4°C storage, it certainly did not match the performance of the CEM formulations for preservation of metabolic function of cells stored in liquid nitrogen. Based on our results of viability and detoxification function the combination of CEM with DMSO, polyethylene glycol and serum provided optimal protection for LN2 frozen cells. Other findings in these studies underlined the importance of the gradual introduction of DMSO in the prefreezing process, the period of osmotic equilibration, and the rapid postthaw withdrawal of this agent to minimize cytotoxic effects at these critical stages. Our freezing methodology provides the foundation for further technological developments in the cryopreservation of the large numbers of cells (billions) that are necessary for extracorporeal liver assist devices.
The effect of smoking on the risk of gestational hypertension

Abstract Data from the 1988 National Maternal and Infant Health Survey were used to examine the effect of smoking on the risk of gestational hypertension (GH). GH was defined as the occurrence of two consecutive diastolic blood pressure readings of at least 90 mmHg after the 20th week of gestation in the absence of proteinuria in subjects normotensive prior to pregnancy. One-hundred ten subjects with gestational hypertension were compared with 4371 subjects free of all hypertensive disorders. Smoking during pregnancy was associated with a reduction in risk of GH overall (Odds Ratio (95% CI) = 0.18 (0.07–0.43)) and within each race and parity subgroup. When the protective effect of smoking was examined by race, black subjects appeared to benefit less from smoking compared with whites but the weaker effect in blacks was attributable to less smoking by blacks. Parous subjects experienced a larger reduction in the risk of GH associated with smoking than nulliparous subjects and this persisted at each dose level of smoking. Neither the protective effect of smoking nor the difference by parity appeared to be due to confounding by race, age, weight gain, alcohol use or marijuana use (adjusted OR (95% CI): nulliparous 0.28 (0.09–0.94) vs. parous 0.10 (0.03–0.30)).
Multiple-time-scale blinking and radiative efficiency of InAs/GaAs microcavity-quantum dot single photon sources

Photon correlations measured over 12 decades in time reveal multiple-time-scale blinking in InAs/GaAs microcavity-quantum dot single-photon sources and enable estimation of quantum dot radiative efficiency. Non-unity efficiencies suggest nanofabrication may produce traps responsible for blinking.
A hospital-based screening program for natural rubber latex allergy.

Background Natural rubber latex (NRL) allergy has become an important occupational health problem for health care workers, of whom approximately 10% are reportedly sensitized. Some medical facilities have chosen to convert entirely to NRL-free gloves, but others have found this to be financially or logistically unfeasible. Objectives The goals of this study were 1) to devise a NRL allergy screening program that could identify sensitized (at-risk) employees for the purpose of providing them with a safe working environment; and 2) to develop a glove conversion plan that would lead to the removal of all NRL gloves from the institution. Methods A multidisciplinary University of Maryland Medical System NRL risk team developed a mandatory NRL screening program for all newly hired employees and any existing employees transferring into or within patient care positions. Employees were screened with a clinical questionnaire and a serology for immunoglobulin (Ig)E anti-NRL. Some employees voluntarily received an experimental NRL skin test to evaluate their skin reactivity to NRL. Each employee reporting respiratory or systemic symptoms associated with NRL exposure was evaluated by an allergist. Results During the 15-month study period from April 1998 to July 1999, 1,795 employees were screened for NRL allergy. Of the whole group, 8% (144 of 1,795) were NRL-specific IgE antibody-positive by CAP radioallergosorbent test (Pharmacia-Upjohn Diagnostics, Kalamazoo, MI) and/or NRL skin test, 57.3% of whom reported symptoms with powdered NRL glove exposure. The NRL IgE-positive rates of nonpatient-care employees (who did not use NRL gloves on a regular basis) and direct patient-care employees was 5.9% and 8.6%, respectively. Most NRL-sensitized employees were successfully accommodated with the use of synthetic gloves and continued to work in the positions for which they were hired. Conclusions The University of Maryland Medical System NRL screening program has been successful in identifying at-risk employees and ensuring them a safe working environment during a progressive conversion of the hospital to a NRL-safe environment.
Comparative aspects of mixed function oxidation by lung and liver of rabbits.

(1974). Comparative Aspects of Mixed Function Oxidation by Lung and Liver of Rabbits. Drug Metabolism Reviews: Vol. 2, No. 1, pp. 1-32.
Perturbation analysis of transient diffraction efficiency of photorefractive materials

Abstract Using a perturbational analysis, we solve the Kukhtarev equation to analyze the transient process of holographic write-in and read-out in a photorefractive material. The diffraction efficiency as a function of various write and read conditions is discussed. Results show that the diffraction efficiency may be designed to either increase or decrease initially during the reading process. Furthermore, the diffracted light is frequency-shifted according to the applied external electric field.
Electrophoretic analysis of membrane proteases in the luteinized rat ovary.

Membrane fractions from fully luteinized rat ovaries contained proteolytic enzymes that were solubilized and reversibly inhibited by the anionic detergent sodium dodecyl sulfate. Electrophoretic analysis in substrate-containing sodium dodecyl sulfate-polyacrylamide slab gels revealed the presence of numerous protease bands in the mol wt range of 26,000 to more than 200,000. When casein served as protease substrate in the gels, enzyme bands of Mr 26,000, 28,000, 30,000, and 90,000 were produced by crude (2,000 × g pellet) ovarian membranes. Gels containing casein and plasminogen also revealed the presence of two plas-minogen activators of Mr 63,000–65,000 and 42,000. Subcellular fractionation of luteinized ovaries by centrifugation in sucrose density gradients indicated that the Mr 90,000 protease and the two plasminogen activators were uniformly distributed among microvillous membranes, basolateral membranes (BLM), and the mitochondrial-lysosomal fraction (MLF). The Mr 26,000, 28,000, and 30,000 proteases...
Sulfated glucuronyl glycolipids reacting with anti-myelin-associated glycoprotein monoclonal antibodies including IgM paraproteins in neuropathy: species distribution and partial characterization of epitopes.

Abstract It was recently established that anti-myelin associated glycoprotein (MAG) IgM paraproteins associated with neuropathy and a substantial number of experimentally produced rat and mouse monoclonal antibodies that react with MAG (e.g. HNK-1) also bind to some sulfated glucuronic acid-containing sphingoglycolipids of human peripheral nerve. A species study revealed that these glycolipids could be detected readily by TLC overlay experiments in the acidic glycolipid fractions from human, monkey, bovine, cat and dog peripheral nerve. The glycolipids were also present in the nerves of rat, mouse, rabbit, guinea pig and chicken, but their concentration was about an order of magnitude lower. These antigenic glycolipids were present in the purified myelin fraction from cat nerve, but their level was not enriched over that in whole homogenate. Partial characterization of the epitopes in the glycolipids was accomplished by comparing binding of the human and experimental monoclonal antibodies to sulfated glucuronyl paragloboside (SGPG), to the desulfated lipid (GPG), and to the methyl ester of the desulfated lipid (MeGPG). All of the human, mouse and rat antibodies reacted with the intact SGPG, but none exhibited binding to MeGPG indicating that either the sulfate or the free car☐yl group on SGPG was required for reactivity. Five out of 11 human IgM paraproteins retained partial and variable reactivity with GPG showing that the sulfate was not absolutely required for binding, while the other 6 did not react with GPG. These results demonstrate idiotypic heterogeneity among the IgM paraproteins. Only 1 of 14 monoclonal antibodies produced experimentally in mice or rats retained reactivity with GPG. The data indicate that the sulfated glucuronic acid moiety of the glycolipid is a critical part of the antigenic determinant for all of the human, mouse and rat monoclonal antibodies tested.
Diagnosis of congenital syphilis by immunofluorescence following fetal death in utero

The etiology of fetal death may be difficult to identify, particularly with the presence of marked fetal maceration and autolysis. Immunofluorescence with human antitreponemal antibody was used in this case to establish a diagnosis of congenital syphilis.
Finance modeling in the delivery of medical care in tertiary-care hospitals in the Department of Veterans Affairs

Background In the mid-1990s, the Department of Veterans Affairs (DVA) implemented the Veterans Equitable Resource Allocation (VERA), a new financial model developed to attempt to better distribute the approximately $18 billion annual budget among roughly 170 Veterans Administration Medical Centers (VAMCs). VERA is based on a Health Maintenance Organization (HMO) model. VERA provides reimbursement to each of the 22 regional Veterans Integrated Service Networks (VISNs), and subsequent VISN distribution to individual VAMCs is based on an individual medical center's enrollment of unique social security numbers (uniques). In HMO vocabulary these are individual "covered lives." Methods Currently available demographic and staffing information regarding the DVA's 23 tertiary hospital systems (Category 7 hospitals) on the KLF database (DVA Austin Data Base) and published information on the DVA website were reviewed. The following was obtained: (1) staffing information-physician and nurse full-time employment equivalent (FTEE) staffing; (2) patient demographics and hospital workload-facility uniques (u), outpatient facility uniques, average daily census (ADC), discharges, and outpatient clinic visits. The following staffing ratios were calculated for both physician and nursing: FTEE/(u/1000), FTEE/(discharges/1000), FTEE/(clinic visits/1000), FTEE/ADC. For all categories the means +/- SD were calculated and correlation coefficients were calculated on pertinent pairings. Results Although categorized as similar tertiary care facilities, the 23 "Group 7" VA hospitals are anything but equivalent when reviewed using the VERA financing model with respect to physician staffing, nurse staffing, and facility uniques. Using VERA methodology, average physician FTEE and total nursing FTEE staffing/(u/1000) are 3.67 +/- 0.89 and 15.53 +/- 3.77, respectively. Correlation statistics of staffing versus unique SSNs demonstrated correlation coefficients of 0.46 and 0.59 with respect to physician and nurse staffing, respectively. On the other hand, when physician FTEE and nursing FTEE staffing were compared with VAMC workload parameters (total ADC, discharges, and outpatient visits), correlation coefficients were more consistent, ranging from 0.62 to 0.86. Conclusions In the VERA model, the reward of a larger annual budget for an individual VAMC or the regional VISN is realized when staffing of VAMCs is minimized, overall provided medical services (especially costly tertiary services) are limited, and the number of covered lives is maximized. A VAMC staffing system that equates medical services delivered in a tertiary VAMC setting based on an HMO model like VERA (where the user population is skewed toward the sicker, older patient) shows decreased correlation when compared with VAMC workload model parameters.
Primary cutaneous nocardiosis.

Seven patients with primary cutaneous nocardiosis were seen during a 20-month period. Six patients had a history of local trauma to an extremity or did frequent yard work. The spectrum of clinical disease included cellulitis, pustules, pyoderma, or lymphocutaneous syndrome mimicking sporotrichosis. Evidence of Nocardia infection elsewhere was absent, and no patient had a serious underlying disease. Nocardia brasiliensis was isolated from four cases, and N asteroides was identified in the other three patients. In two patients, disease resolved without chemotherapy, while a short course of a sulfonamide with or without trimethoprim therapy was successful in the remaining cases. The relatively benign nature of this disease, the usual failure to obtain cultures of superficial skin infections, and our accumulation of seven cases in less than two years suggest this disease is more common than previously recognized. ( JAMA 242:333-336, 1979)
Structural Basis for Influence of Viral Glycans on Ligand Binding by Influenza Hemagglutinin

Binding of cell surface glycans by influenza hemagglutinin controls viral attachment and infection of host cells. This binding is a three-way interaction between viral proteins, host glycans, and viral glycans; many structural details of this interaction have been difficult to resolve. Here, we use a series of 100-ns molecular dynamics simulations to further analyze available crystallographic data on hemagglutinin-ligand interactions. Based on our simulations, we predict that the viral glycans contact the host glycans within 1–2 residues of the ligand-binding site. We also predict that the glycan-glycan interactions contain both stabilizing and destabilizing components. These predictions suggest a structural means to explain why changes to viral glycosylation alter the efficiency and selectivity of ligand binding. We also predict that the proximity of these interactions to the ligand-binding pocket will impact the binding affinity of small glycomimetic ligands analogous to the influenza neuraminidase inhibitors currently in clinical use.