cssi/SciSciGPT-SciSciNet huggingface dataset:
In vivo and ex vivo haematopoietic stem cell expansion.

Purpose of review Haematopoietic stem cells (HSCs) are characterized by two key features: self-renewal ability and multilineage differentiation potential. Through these cellular activities, HSCs sustain blood and immune system homeostasis throughout life and can also reconstitute the entire haematopoietic system within a bone marrow ablated recipient. This approach of HSC transplantation is used clinically as a curative treatment option for numerous haematological diseases, both malignant and nonmalignant. Recent findings Elucidation of the mechanism of HSC expansion represents a major focus within haematology. Here, we review the recent progress towards understanding HSC expansion in vivo and ex vivo, including a discussion of recent clonal transplantation assays and the development of novel ex vivo culture systems. Summary Recent findings provide exciting promise for improving the safety and efficacy of current HSC-based therapies as well as for the development of new therapeutic paradigms.
Method, Mediations, and the Moral Dimensions of Preimplantation Genetic Diagnosis

In responding to Professor Smolin’s hypothetical about Brenda and John Smith’s reproductive options, this essay focuses on two matters. First, the essay explores one aspect of the several options facing the Smiths—that involving preimplantation genetic diagnosis. Second, and more important, this essay suggests a methodological approach to bioethical conundrums such as those raised by the Smith hypothetical. Concepts of morality flow from and reflect a society’s ideology. Understandings of the world and the way people live their everyday lives are fundamentally connected to the value people place on themselves, other people, relationships, events, and things in the world. That is to say, moral beliefs are inseparable from larger systems of meaning. From within a society such as our own that has jettisoned many of the frames within which social truths were once anchored, it is
Meta-analysis of Total Effect Decomposition in the Presence of Multiple Mediators: The Example of Schizophrenia Treatment.

Background Causal mediation analysis addresses mechanistic questions by decomposing and quantifying effects operating through different pathways. Because most individual studies are underpowered to detect mediating effects, we outlined a parametric approach to meta-analyzing causal mediation and interaction analyses with multiple mediators, compared it with a bootstrap-based alternative, and discussed its limitations. Methods We employed fixed- and random-effects multivariate meta-analyses to integrate evidence on treatment-mediators and mediators-outcome associations across trials. We estimated path-specific effects as functions of meta-analyzed regression coefficients; we obtained standard errors using the delta method. We evaluated the performance of this approach in simulations and applied it to assess the mediating roles of positive symptoms of schizophrenia and weight gain in the treatment effect of paliperidone ER on negative symptoms across four efficacy trials. Results Both simulations and the application showed that the meta-analytic approaches increased statistical power. In the application, we observed substantial mediating effects of positive symptoms (proportions mediated from fixed-effects meta-analysis: (Equation is included in full-text article.)). Weight gain may have beneficial mediating effects; however, such benefit may disappear at high doses when metabolic side effects were excessive. Conclusions Meta-analyzing causal mediation analysis combines evidence from multiple sources and improves power. Targeting positive symptoms may be an effective way to reduce negative symptoms that are challenging to treat. Future work should focus on extending the existing methods to allow for more flexible modeling of mediation.
Ultrathin platinum nanowire based electrodes for high-efficiency hydrogen generation in practical electrolyzer cells

Abstract Significant reduction of noble metal catalyst loading and simplification of electrode fabrication are urgently needed in order to lower the cost of proton exchange membrane electrolyzer cells (PEMECs) for large-scale hydrogen production. Herein, we report an integrated electrode design comprising in-situ grown platinum nanowires (PtNW) on ultrathin titanium liquid/gas diffusion layers (LGDLs) via a cost-effective and green chemical synthesis approach. The ultrathin integrated PtNW electrodes showed a low cell voltage of 1.643 V and high efficiency of 90.08% at 1000 mA cm−2 using about 15 times lower catalyst loadings than a conventional catalyst-coated membrane in PEMEC tests. Ex-situ electrochemical characterizations and microscale visualizations further reveal that PtNW electrodes display highly efficient hydrogen evolution reactions and excellent electrode durability due to high active surface area, favorable bubble detachment, and structural stability. This work provides new insights into catalyst layer design and facile ultrathin electrode fabrication for more compact and low-cost PEM electrolyzers, fuel cells and other systems.
Whose Motive Matters?: Discrimination in Multi-Actor Employment Decision Making

Disparate treatment claims require a finding of an intent to discriminate. The search for discriminatory intent or motive in disparate treatment cases often is envisioned as an attempt to determine whether a supervisor, despite his denials, consciously acted out of bias, animus or on the basis of inaccurate or stigmatizing stereotypes in making an employment decision. Many employment decisions, however, are not made by a single individual. Sometimes, employment decisions are made after a recommendation works its way up a chain of authority. Sometimes, they are made by a committee or group, and sometimes, the decision making process incorporates elements of both. Some of the participants in the decision making process may act for prohibited reasons, while others may act for reasons having nothing to do with a plaintiff's protected class status. In such cases, whose motive matters? An ultimate decision maker or members of a decision making group may be, and often are, unaware that others involved in the process have based their decisions, in whole or in part, on an employee's protected-group status. Courts facing such claims generally have not considered that unawareness a sufficient basis for depriving a plaintiff of her discrimination claim. Instead, they have examined whether impermissible considerations in one part of the decision making chain caused the action to occur, in whole or in part. These multiple actor cases provide a useful model for the intent inquiry in individual decision maker situations as well. Just as persons involved in a decision making process may be unaware of the motives of others, individuals, as work in social cognition has demonstrated, are often unaware of their own biases. Implicit stereotypes can influence an individual's decision making in much the same way as an invidiously motivated supervisor can influence the actions of her superiors. In either context, the fact-finder should ask not whether decision makers made conscious use of the plaintiff's group status in the decision making process, but whether the plaintiff's group status caused the challenged decision to be made, in whole or in part. But causation alone, the article submits, is not a sufficient basis for employer liability. Under principles articulated by the Supreme Court in Burlington Industries v. Ellerth, the action complained of must be attributable to the employer, either directly or vicariously. Moreover, there must exist an unbroken chain of causation between these actions and the harm suffered by the plaintiff.
Scurvy: A Case Report and Literature Review.

Scurvy is a rare disease which can manifest in a variety of presentations. Classically, scurvy is associated with poor dentition and bleeding diatheses. Rarely, scurvy can present with life-threatening hemodynamical instability. Herein, we report the case of a 69-year-old female with a history of hypertension and depression who presented with four months of weakness and a 20-pound weight loss. Her presentation was complicated by lower extremity bruising and myalgias over the last three weeks. The patient's blood pressure in the emergency department was 86/54 mmHg. On further examination, she had poor dentition and extensive ecchymoses in different stages of resolution over her posterior thighs and calves. The patient was also noted to have perifollicular hemorrhages. An ascorbic acid level was checked and the result was 0.0 mg/dL (normal range: 0.4 to 2.0 mg/dL). During her admission, she slowly improved with a provided diet and multivitamins. Her blood pressure consistently remained over 120/65 mmHg. The patient was advised to adjust her diet and take supplemental ascorbic acid. On a follow-up visit two weeks later, the patient endorsed an improvement in pain and exercise tolerance and was noted to have marked improvement in skin findings. Ascorbic acid is an essential piece of multiple biochemical pathways. Humans are required to attain ascorbic acid from their diet. People who consume diets lacking in ascorbic acid develop scurvy.
Sex and Race Differences in the Risk of Ischemic Stroke Associated With Fasting Blood Glucose in REGARDS

Objective To investigate sex and race differences in the association between fasting blood glucose (FBG) and risk of ischemic stroke (IS). Methods This prospective longitudinal cohort study included adults age ≥45 years at baseline in the Reasons for Geographic And Racial Differences in Stroke Study, followed for a median of 11.4 years. The exposure was baseline FBG (mg/dL); suspected IS events were ascertained by phone every 6 months and were physician-adjudicated. Cox proportional hazards were used to assess the adjusted sex/race-specific associations between FBG (by category and as a restricted cubic spline) and incident IS. Results Of 20,338 participants, mean age was 64.5 (SD 9.3) years, 38.7% were Black, 55.4% were women, 16.2% were using diabetes medications, and 954 IS events occurred. Compared to FBG Conclusions Sex differences in the strength and shape of the association between FBG and IS are likely driving the significant differences in the association between FBG and IS across race/sex subgroups. These findings should be explored further and may inform tailored stroke prevention guidelines.
Evaluation of a cone penetration test thin-layer correction procedure in the context of global liquefaction model performance

Abstract Engineering geologists routinely perform liquefaction hazard assessments using data from the cone penetration test (CPT). However, the volume of soil mobilized by the CPT acts as a low-pass filter on the true stratigraphy, potentially removing information such as the data defining a thin layer of soil or the interface between two dissimilar soils. The Boulanger and DeJong (2018) CPT inversion procedure, which aims to correct these effects, is herein evaluated in the context of CPT-based liquefaction model performance. Using over 15,000 case-histories from 24 earthquakes parsed into 2 datasets, 18 different liquefaction models are studied, resulting in 36 performance trials. In 1 of these trials, the CPT inversion procedure increases model efficiency to a statistically significant degree, but in 23 others it significantly decreases efficiency. This decline in performance tends to grow as profiles become more stratified. To explore remedies, a liquefaction triggering curve is rederived from inverted CPT data, such that its training and forward implementation are made consistent. Nonetheless, this exacerbates the decline in prediction efficiency. Ultimately, the results of this study are not a direct assessment of the pioneering Boulanger and DeJong (2018) procedure. However, the results do provide evidence that this procedure – when applied to existing CPT-based liquefaction models – may provide no demonstrable performance benefit.
Incidental Finding of Bilateral Acute Pulmonary Emboli in a Patient With Asymptomatic COVID-19 Infection.

A 58-year-old male with a history of hypertension, dyslipidemia, osteoarthritis of both knees, and morbid obesity presented to the emergency department for opioid detoxification. He complained of generalized soreness, anxiety, and difficulty sleeping but denied signs and symptoms suggestive of coronavirus disease 2019 (COVID-19) infection. His COVID-19 polymerase chain reaction (PCR) result came back positive, and his D-dimer level was 5373 ng/mL. A computed tomography pulmonary angiogram showed a moderate burden of bilateral acute pulmonary emboli. He was managed with enoxaparin sodium subcutaneous therapeutic dose for three days, followed by oral apixaban 10 mg twice a day for seven days and then 5 mg twice a day for six months. To date, the rate of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 has not been reported, and current guidelines do not recommend thromboprophylaxis for these patients.
EVALI Vaping Liquids Part 2: Mass Spectrometric Identification of Diluents and Additives

The vaping liquid additive vitamin E acetate (VEA) was strongly linked to the 2019 United States nationwide outbreak of pulmonary lung illness (EVALI) associated with e-cigarettes or vaping liquids. Our laboratory received over 1,000 vaping liquid products for identification of the vaping liquid additives, including hundreds of vaping products from EVALI patients. In this work, we present results obtained for the GC-MS identification of numerous vaping liquid additives in a large subset of ca. 300 Cannabis vaping liquids, including vitamin E acetate, medium chain triglycerides oil (MCT oil), polyethylene glycols, squalane, triethyl citrate, dipropylene glycol dibenzoate (DPG dibenzoate), pine rosin acids, pine rosin methyl esters, and sucrose acetate isobutyrate (SAIB). Confirmation of DPG dibenzoate and SAIB using LC-HRMS is also presented. GC-MS analysis for additives identified as the parent compounds was conducted after separation on a commercial 5% phenyl phase. GC-MS analysis for additives identified as the trimethylsilyl derivatives was conducted after separation on a commercial 35% silphenylene phase. LC-HRMS analysis was conducted using gradient elution with either C18 or phenyl-hexyl phases and determination of exact masses for the target compounds. In addition to providing rapid methods for the identification of vaping liquid additives, this work highlights the variety of Cannabis vaping liquid additives in current use.
Experimental study of thermo-mechanical behavior of SiC composite tubing under high temperature gradient using solid surrogate

Abstract Nuclear grade silicon carbide fiber (SiCf) reinforced silicon carbide matrix (SiCm) composite is a promising candidate material for accident tolerance fuel (ATF) cladding. A major challenge is ensuring the mechanical robustness of the ceramic cladding under accident conditions. In this work the high temperature mechanical response of a SiCf–SiCm composite tubing is studied using a novel thermo-mechanical test method. A solid surrogate tube is placed within and bonded to the SiCf–SiCm sample tube using a ceramic adhesive. The bonded tube pair is heated from the center using a ceramic glower. During testing, the outer surface temperature of the SiC sample tube rises up to 1274 K, and a steep temperature gradient develops through the thickness of the tube pair. Due to CTE mismatch and the temperature gradient, the solid surrogate tube induces high tensile stress in the SiC sample. During testing, 3D digital image correlation (DIC) method is used to map the strains on the outer surface of the SiC-composite, and acoustic emissions (AE) are monitored to detect the onset and progress of material damage. The thermo-mechanical behavior of SiC-composite sample is compared with that of monolithic SiC samples. Finite element models are developed to estimate stress–strain distribution within the tube assembly. Model predicted surface strain matches the measured surface strain using the DIC method. AE activities indicated a progressive damage process for SiCf–SiCm composite samples. For the composites tested in this study, the threshold mechanical hoop strain for matrix micro-cracking to initiate in SiCf–SiCm sample is found to be ∼300 microstrain.
A new robust Chinese remainder theorem with improved performance in frequency estimation from undersampled waveforms

A robust Chinese remainder theorem (CRT) has been recently proposed, that is, a large integer less than the least common multiple (lcm) of all the moduli can be robustly reconstructed from its erroneous remainders when all remainder errors are assumed small. In this paper, we propose a new robust CRT when a combined occurrence of multiple unrestricted errors and an arbitrary number of small errors is in the remainders, where a determinable integer is required to be less than the lcm of a subset of the moduli. A reconstruction algorithm is also proposed. We then apply the reconstruction algorithm to frequency estimation from undersampled waveforms. It shows that the newly proposed algorithm leads to a better performance than the previous existing robust CRT algorithm. HighlightsA new robust CRT is proposed when multiple unrestricted errors combined with an arbitrary number of small errors are in the remainders.A new robust reconstruction algorithm is proposed.The proposed algorithm leads to a better performance in frequency estimation from undersampled waveforms than the previous one.
The Dianoiac Thread of the Logos Running Through Our Polyphonic Exploration of the Pursuit of Destiny

The focus of our attention in the foregoing inquiry was the subjacent question — Do we pursue the quest of our destiny within our soul alone, isolating it from other human beings? On the contrary, we have been trying to show that any type of meaningfulness in our lives other than its primitive struggle for survival may be accomplished only by means of a “communication” between the self and the Other, by entering with him in the rapport of what we would call “inward creative reciprocity.” The specifically personal quest after the meaningfulness of life is carried out by a dialogue between two persons, a dialogue which is essential to any human relation other than those of a strictly utilitarian type. There is, however, more to this type of “dialogue” than the “dialogue philosophies” issuing from Martin Buber and Emmanuel Levinas emphasize; there is also more to the type of “communication” under discussion than can be found in Karl Jaspers’ beautiful descriptions. In fact in “communication” as well as in the “dialogical” approach some central questions remains unanswered.
Peroxisome proliferator-activated receptors and cancer: challenges and opportunities

Peroxisome proliferator-activated receptors (PPARs), members of the nuclear hormone receptor superfamily, function as transcription factors and modulators of gene expression. These actions allow PPARs to regulate a variety of biological processes and to play a significant role in several diseases and conditions. The current literature describes frequently opposing and paradoxical roles for the three PPAR isotypes, PPARα, PPARβ/δ and PPARγ, in cancer. While some studies have implicated PPARs in the promotion and development of cancer, others, in contrast, have presented evidence for a protective role for these receptors against cancer. In some tissues, the expression level of these receptors and/or their activation correlates with a positive outcome against cancer, while, in other tissue types, their expression and activation have the opposite effect. These disparate findings raise the possibility of (i) PPAR receptor-independent effects, including effects on receptors other than PPARs by the utilized ligands; (ii) cancer stage-specific effect; and/or (iii) differences in essential ligand-related pharmacokinetic considerations. In this review, we highlight the latest available studies on the role of the various PPAR isotypes in cancer in several major organs and present challenges as well as promising opportunities in the field.
Functioning of Adolescents with Symptoms of Disturbed Sleep.

The objective of the study was to examine the association between disturbed sleep and the functioning of adolescents, in particular cumulative effects on functioning across multiple life domains. Data from a large, school-based survey (n = 5,423) were used to examine the association between eight indicators of psychological, interpersonal, and somatic functioning and symptoms of insomnia and hypersomnia among adolescents. The strongest correlates of insomnia were disturbed mood (OR = 5.9), fatigue (OR = 7.4), and suicidal ideation (OR = 3.4). The same pattern held for hypersomnia, although the associations were not as strong for fatigue (OR = 6.8), mood disturbance (OR = 3.5), and suicide ideation (OR = 2.8). Youths who experienced both insomnia and hypersomnia had greater odds of psychological, interpersonal, and somatic dysfunction than youths who had experienced only one sleep disturbance. Cumulative effects of sleep problems were pronounced, with 27.6% of those with hypersomnia, 41.7% of those with insomnia, and 59.2% of those with both sleep problems reporting three or more types of dysfunction. The results suggest that adolescents experiencing disturbed sleep also experience a range of deficits in functioning. Further, youths with disturbed sleep are more likely to manifest multiple deficits in functioning. From the available evidence, however, it is not possible to specify what the causal pathways are. What are needed are cohort studies designed to examine the association of disturbed sleep and functional impairment among adolescents prospectively.
Geography and war

Abstract The ‘New Geography’ in England, usually identified with the establishment of geographical teaching in the universities of Oxford and Cambridge in 1887–1888, was based on Mackinder's interpretation of the subject in his paper ‘On the scope and methods of geography’ in 1887. Geography was also of concern in areas of national life other than purely academic, however, notably in the military, colonial administration and commerce. British reverses in the South African War (1899–1902), followed by the Russian defeat in the Russo-Japanese War (1904–1905), focused attention on the importance of geography in the Army in the period 1899–1914. Existing deficiencies were savagely denounced in an article in The Times by Colonel C.A.C. Repington on ‘Geography and war’ in November 1904. Recognition of the importance of geography and cartography coincided with the reform of Army administration, especially the formation of the General Staff in 1906, and a new emphasis on the professional training of Army officers. The ‘New Geography’ thus, found a practical role in the ‘New Army’, complementary to that conventionally understood in the universities. The conduct of the Tibet expedition under Younghusband in 1903–1904 symbolizes this new attention to geographical matters in the Army of the day.
Comprehensive performance analysis of radars using different types of sweep modulation

A comprehensive analysis of different types of sweep modulation is presented, together with suggestions for the transmitting pulse which fulfil the basic requirements of modern radars. Linear frequency modulation is effective at lower altitudes under the condition that the time-bandwidth product is not too large. Exponential modulation is suited to medium altitudes, and linear period modulation to higher altitudes. >
The expected cost of default

Abstract The sample of observed defaults significantly understates the average firm׳s true expected cost of default due to a sample selection bias. I use a dynamic capital structure model to estimate firm-specific expected default costs and quantify the selection bias. The average firm expects to lose 45% of firm value in default, a cost higher than existing estimates. However, the average cost among defaulted firms in the estimated model is only 25%, a value consistent with existing empirical estimates from observed defaults. This substantial selection bias helps to reconcile the levels of leverage and default costs observed in the data.
Gestation length in rhesus macaques ( Macaca mulatta )

We describe some of the sources of variation in gestation length among rhesus macaques. the data were obtained from the timed-mating breeding program at the California Regional Primate Research Center (CRPRC). Information about approximately 700 pregnancies that resulted in spontaneous vaginal deliveries of liveborn young is presented. The average length of these pregnancies was 166.5 days. In this population, older females with higher parities had significantly longer pregnancies and significantly heavier infants than other females did. Other factors, including infant sex, month of conception, maternal reproductive history, and paternal identity, had no consistent effect upon gestation length.
The use of measures of entropy in evaluating human supervisory control of a manufacturing system

The use of measures of entropy for evaluating human supervisory control performance in a flexible manufacturing system is described. The measures are especially useful in explaining performance when graphic displays intended for enhancing human pattern-recognition capabilities are available and under task conditions with contrasting types of workload.
Nitric Acid Dehydration Using Mixed Perfluorosulfonate and -carboxylate Ionomer Membranes

Investigations confirmed the feasibility and potential advantage of using mixed perfluorosulfonate/carboxylate membranes for nitric acid dehydration. Experimentation consisted of in situ generation of pure sulfonate and mixed sulfonate/carboxylate (as high as 71 mol % carboxylate) polymer films from a perfluorosulfonyl fluoride precursor membrane, the characterization of the material, and a study of the transport characteristics of these membranes. The carboxylate concentration was determined using direct Fourier transform infrared and X-ray fluorescence spectroscopy. Nitric acid dehydration transport tests confirmed that bulk fluxes decreased and the water separation factor dramatically increased as the carboxylate side-chain content increased to 53 mol %.
Structure and function of the BAH-containing domain of Orc1p in epigenetic silencing.

The N‐terminal domain of the largest subunit of the Saccharomyces cerevisiae origin recognition complex (Orc1p) functions in transcriptional silencing and contains a bromo‐adjacent homology (BAH) domain found in some chromatin‐associated proteins including Sir3p. The 2.2 A crystal structure of the N‐terminal domain of Orc1p revealed a BAH core and a non‐conserved helical sub‐domain. Mutational analyses demonstrated that the helical sub‐domain was necessary and sufficient to bind Sir1p, and critical for targeting Sir1p primarily to the cis ‐acting E silencers at the HMR and HML silent chromatin domains. In the absence of the BAH domain, ∼14–20% of cells in a population were silenced at the HML locus. Moreover, the distributions of the Sir2p, Sir3p and Sir4p proteins, while normal, were at levels lower than found in wild‐type cells. Thus, in the absence of the Orc1p BAH domain, HML resembled silencing of genes adjacent to telomeres. These data are consistent with the view that the Orc1p–Sir1p interaction at the E silencers ensures stable inheritance of pre‐established Sir2p, Sir3p and Sir4p complexes at the silent mating type loci.
Motivational Interviewing and Rehabilitation Counseling Practice

This article explores commonalities between rehabilitation counseling and the counseling approach known as motivational interviewing. Motivational interviewing is an empirically supported, client-c...
Effects of class size on alternative educational outcomes across disciplines

Abstract This is the first study to use self-reported ratings of student learning, instructor recommendations, and course recommendations as the outcome measure to estimate class size effects, doing so across 24 disciplines. Fixed-effects models controlling for heterogeneous courses and instructors reveal that increasing enrollment has negative and significant effects on student satisfaction in Sociology, Political Science, Computer Science and Engineering, and Mechanical and Aerospace Engineering. Educational outcomes in Linguistics, Psychology, Biological Sciences, Chemistry, Math, Physics, Cognitive Sciences, Visual Arts, History, and Philosophy are unaffected by class size. Other disciplines, including Economics, have inconclusive findings. No discipline benefits from increasing enrollment.
Robert Gwathmey: The Life and Art of a Passionate Observer

American artist Robert Gwathmey (1903-1988) was a leading member of the Social Realist movement that flourished from the 1930s through the 1950s. Like his fellow Social Realists, Gwathmey used his art to expose privilege and pretense, demand social justice and call for major changes in the prevailing socioeconomic system. Gwathmey was an 8th-generation Virginian, and throughout his life his main artistic themes were race relations and his native South. He is perhaps best remembered as the first white American painter to depict African Americans in an unromanticized, respectful manner. Using a unique style that combined a deliberate two-dimensional flatness with deep and vivid colours, Gwathmey illuminated the inherent dignity of the tenant farmers and sharecroppers who were his subjects. As a lifelong activist against injustice, Gwathmey was kept under surveillance by the FBI for nearly 30 years. Using Gwathmey's FBI file, along with numerous interviews and archival records, Michael Kammen crafts a portrait of an engaging American painter in the midst of dramatic social and political change.
EXPERIMENTAL EPILEPSY OF BRAIN-STEM ORIGIN.

Abstract Experiments were performed in the anesthetized cat. 1.(1) The reticular substance of the midbrain, pons and medulla is capable of responding to the injection of small doses of aqueous penicillin in the same manner as the cerebral cortex and thalamus, i.e. with the production of epileptiform sporadic discharges. 2.(2) Unlike the spiking focus produced in one area of a cerebral hemisphere or lateral in the thalamus, that produced unilaterally in the brain-stem reticular formation is immediately and equally projected to both cerebral cortices. This is also true for the organized ictal episodes. 3.(3) Other areas of the brain-stem which are outside of the reticular substance may react with focal spiking in the manner of cerebral cortical foci.
Nonlinear Simulation Of Raman Free-Electron Lasers With Axial Guide Fields

The nonlinear evolution of Raman free-electron lasers in the presence of an axial guide-field is investigated numerically in an amplifier configuration. The nonlinear currents which mediate the interaction are computed by means of an average over particle phases, and the inclusion of fluctuating space-charge fields in the formulation permits the investigation of both the stimulated Raman and Compton scattering regimes. Initial conditions are chosen to describe the injection of a monoenergetic beam into the interaction region composed of a uniform axial guide field and a helical wiggler field which increases adiabatically to a constant level. After an initial transient phase, the results show a region of exponential growth of the radiation field which is in excellent agreement with linear theory. Saturation occurs by means of particle trapping. The efficiency of the interaction has been studied for a wide range of axial guide fields, and substantial enhancements have been found relative to the zero-guide-field limit.© (1984) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Inorganic mercury dissociates preassembled Fas/CD95 receptor oligomers in T lymphocytes

Genetically susceptible rodents exposed to low burdens of inorganic mercury (Hg2+) develop autoimmune disease. Previous studies have shown that low, noncytotoxic levels of Hg2+ inhibit Fas-mediated apoptosis in T cells. These results suggest that inhibition of the Fas death receptor pathway potentially contributes to autoimmune disease after Hg2+ exposure, as a consequence of disruption of peripheral tolerance. The formation of active death inducing signaling complexes (DISC) following CD95/Fas receptor oligomerization is a primary step in the Fas-mediated apoptotic pathway. Other recent studies have shown that Hg2+ at concentrations that inhibit apoptosis also inhibit formation of active DISC, suggesting that inhibition of DISC is the mechanism responsible for Hg2+-mediated inhibition of apotosis. Preassociated Fas receptors have been implicated as key elements necessary for the production of functional DISC. We present evidence in this study showing that low and nontoxic concentrations of Hg2+ induce the dissociation of preassembled Fas receptor complexes in Jurkat T cells. Thus, this Hg2+-induced event should subsequently decrease the amount of preassembled Fas available for DISC formation, potentially resulting in the attenuation of Fas-mediated apoptosis in T lymphocytes.
Reactive sulfur species: kinetics and mechanism of the reaction of hypothiocyanous acid with cyanide to give dicyanosulfide in aqueous solution.

The chief sources of cyanide (CN−) in humans are tobacco and occupationally derived smoke, inflammation [vis-a-vis myeloperoxidase (MPO)-induced chlorination of glycine], and microbial cyanogenesis...
Hyperbaric oxygen therapy and cerebral ischemia: neuroprotective mechanisms

Abstract Introduction: Numerous studies have demonstrated a protective effect of hyperbaric oxygen therapy in experimental ischemic brain injury, and many physiological and molecular mechanisms of hyperbaric oxygen therapy-related neuroprotection have been identified. Methods: Review of articles pertaining to hyperbaric oxygen therapy and cerebral ischemia in the National Library of Medicine and National Institutes of Health database, emphasizing mechanisms of hyperbaric oxygen therapy-related neuroprotection. Results: Hyperbaric oxygen therapy has been shown to ameliorate brain injury in a variety of animal models including focal cerebral ischemia, global cerebral ischemia, neonatal hypoxia–ischemia and subarachnoid hemorrhage. Small human trials of hyperbaric oxygen therapy in focal ischemia have not shown benefit, although one trial of hyperbaric oxygen therapy before cardiopulmonary bypass demonstrated improved neuropsychological and inflammatory outcomes with hyperbaric oxygen therapy. Hyperbaric oxy...
Spectroelectrochemical study of the cytochrome a site in carbon monoxide inhibited cytochrome c oxidase

The reduction potential of the cytochrome a site in the carbon monoxide derivative of beef heart cytochrome c oxidase has been studied under a variety of conditions by thin-layer spectroelectrochemistry. The reduction potential exhibits no ionic strength dependence and only a 9 mV/pH unit dependence between pH 6.5 and 8.5. The weak pH dependence indicates that protonation of the protein is not stoichiometrically linked to oxidoreduction over the pH range examined. The temperature dependence of the reduction potential implies a relatively large standard entropy of reduction of cytochrome a. The measured thermodynamic parameters for reduction of cyctochrome a are (all relative to the normal hydrogen electrode) delta Go'(25 degrees C) = -6.37 kcal mol-1, delta Ho' = -21.5 kcal mol-1, and delta So' = -50.8 eu. When cytochrome c is bound to the oxidase, the reduction potential of cytochrome a and its temperature dependence are not measurably affected. Under all conditions studied, the cytochrome a site did not exhibit simple Nernstian n = 1 behavior. The titration behavior of the site is consistent with a moderately strong anticooperative interaction between cytochrome a and CuA [Wang, H., Blair, D. F., Ellis, W. R., Jr., Gray, H. B., & Chan, S. I. (1985) Biochemistry (following paper in this issue)].
Elevated aromatase expression correlates with cervical carcinoma progression

Abstract Objectives We have previously demonstrated that aromatase mRNA is induced in cervical carcinomas compared to normal tissue, suggesting that in situ aromatase expression leading to elevated local estrogen production may contribute to cervical carcinogensis. Our objectives are to examine 1) whether aromatase protein and activity are induced in cervical carcinomas, 2) aromatase expression correlates with disease stage, and 3) inflammatory cytokines (e.g., IL-6 and TNFα) may correlate with aromatase expression. Methods RNA and protein were isolated from human cervical carcinomas and normal cervical biopsies to examine aromatase expression, using real-time RT-PCR, Western blot analysis, and immunohistochemistry. Aromatase activity in tissue was measured using the tritiated water release method. IL-6 and TNFα expression was also examined. Results Aromatase protein and activity levels were increased in cervical carcinomas compared to normal tissue. RNA levels correlated significantly with disease progression, with highest aromatase expression detected in stage IV tumors ( p R 2 =0.77). Aromatase promoters 1.3 and 1.4 were elevated in cervical carcinomas and in cervical cancer cells. The expression of inflammatory cytokines IL-6 and TNFα, known to induce aromatase, significantly correlated with aromatase expression ( R 2 >0.9). TNFα treatment induced aromatase expression in cervical cancer cells. Conclusion Increased aromatase protein and activity in cervical carcinomas and the correlation of its expression with disease stage implicates it in cervical carcinogenesis. The correlation of IL-6 and TNFα expression with aromatase suggests that these inflammatory cytokines may induce aromatase expression, which is confirmed by induction of aromatase expression due to TNFα treatment of cervical cancer cells.
Expectancy as basically a short-term process.

Expectancy in stuttering is investigated under conditions that approximate more closely than in previous work the circumstances and mode in which expectancy is purported to operate. The results ind...
Imaging following bariatric procedures: Roux-en-Y gastric bypass, gastric sleeve, and biliopancreatic diversion.

Morbid obesity remains as a common and increasing health problem. Due to limited long-term success with nonsurgical weight loss measures for morbid obesity, bariatric surgery is being performed more and more often in both academic and private practice settings and has proven to be an effective treatment option with sustained weight loss, decreased morbidity, reversal of comorbidities, and prolonged life expectancies [Am J Clin Nutr 55:615S–619S, 1992; Brolin, Nutrition 12:403–404, 1996; Fisher and Schauer, Am J Surg 184:9S–16S 2002]. The Roux-en-Y gastric bypass, biliopancreatic diversion, and gastric sleeve will be discussed in terms of their expected imaging appearance and potential complications.
Strain softening of faults and earthquake precursors

Abstract A model for a strike-slip fault is proposed in which an instability (earthquake) and/or stable fault slip is produced by strain softening of the fault zone. The form of the fault zone constitutive law and the stiffness and dimension of the surrounding elastic plates determine the fault slip and plate strain as a function of time and the potential for instability. An instability is predictable from a developing plot of fault slip or plate strain if a single parameter, the maximum strain softening slope of the fault zone constitutive law is known. The amount of precursory fault creep and plate strain and hence the reliability and resolution of the prediction depends on the form of the constitutive law. If the rate of strain softening is rapid, precursors are virtually absent. For very slow rates of strain softening precursors are large but temporal resolution of the expected instability may be poor. The friction law on a fault segment may be inferred from observations of fault slip or surface strain as a function of time.
Alkene and Alkyne Insertion Reactions of a Rhenium(III) Alkoxide−Hydride Cluster

Alkene and alkyne insertion reactions of Re3(μ-O-i-Pr)3(H)(O-i-Pr)5 were examined. Re3(μ-O-i-Pr)3(H)(O-i-Pr)5 reacts with ethylene to give Re3(μ-O-i-Pr)3Et(O-i-Pr)5 and with isobutylene to give Re3(μ-O-i-Pr)3(i-Bu)(O-i-Pr)5 reversibly. In solution both alkyl clusters reversibly β-hydrogen eliminate acetone from a Re(O-i-Pr)2 center to yield Re3(μ-O-i-Pr)3(H)(R)(O-i-Pr)4. For Re3(μ-O-i-Pr)3Et(O-i-Pr)5 the alkoxide β-hydrogen elimination equilibrium occurs with thermodynamic parameters ΔH° = 13.2 ± 0.7 kcal/mol and ΔS° = 24.1 ± 2.2 cal/(mol·deg) and activation parameters ΔH⧧ = 17.6 ± 1.0 kcal/mol and ΔS⧧ = −25.0 ± 3.1 cal/(mol·deg). Re3(μ-O-i-Pr)3H(O-i-Pr)5 reacts with 2-butyne to yield Re3(μ-O-i-Pr)3(η1-CMeC(H)Me)(O-i-Pr)5 and with phenylacetylene to give a 1:2 mixture of Re3(μ-O-i-Pr)3(η1-CPhCH2)(O-i-Pr)5 and Re3(μ-O-i-Pr)3(η1-CHC(H)Ph)(O-i-Pr)5, respectively. The minor isomer reversibly eliminates acetone to yield Re3(μ-O-i-Pr)3(H)(η1-CPhCH2)(O-i-Pr)4 and reacts further with phenylacetylene. The major is...
Mechanisms of Drug Action: The Potential of Dimethylfumarate for the Treatment of neoplasms

A middle-aged gentleman who recently moved from Germany presents at your office for the first time. He has a long history of psoriasis and has been treated with multiple modalities, including UV radiation and the medication dimethylfumarate (DMF). You note that, despite his history of severe psoriasis, his skin does not show many psoriatic plaques. Additionally, despite his use of phototherapy and natural sunlight to help control his psoriasis, you notice that he does not have any cancerous or precancerous skin lesions.
Asthma symptoms, severity, and drug therapy: a prospective study of effects on 2205 pregnancies☆

Abstract Objective To prospectively examine in pregnant women whether asthma or asthma therapy influenced preterm delivery, intrauterine grown restriction (IUGR), or birthweight. Methods We enrolled 873 pregnant women with a history of asthma, of whom 778 experienced asthma symptoms or took medication, and 1333 women with no asthma history, including 884 women with neither asthma diagnosis nor symptoms and 449 with symptoms but no diagnosis. Asthma symptoms, medication, and severity were classified according to 2002 Global Initiative for Asthma guidelines. Results Preterm delivery was not associated with asthma diagnosis, severity, or symptoms but was associated with use of controller medications, independent of symptoms, specifically oral steroids and theophylline. Gestation was reduced by 2.22 weeks in women using oral steroids daily ( P = .001) and 1.11 weeks after theophylline ( P = .002). We observed a 24% (5–47%) increased risk for IUGR with each increased symptom step, which increased further in symptomatic women with no asthma diagnosis (31%, 4–65%) compared with women with neither asthma nor symptoms. Conclusion We found no effect of asthma symptoms or severity on preterm delivery but observed increased risks associated with use of oral steroid and theophylline. Intrauterine growth restriction was associated with asthma severity, which possibly reflects a hypoxic fetal effect. Women with asthma symptoms but no diagnosis were at particular risk of undermedication and delivering IUGR infants. These observations support guidelines that advocate active management of pregnant patients with mild or moderate asthma with β 2 agonists, with oral steroids added only if severity increases. Symptomatic patients without an asthma diagnosis might need to be equally managed.
Field-Cage Assessment of Trichogramma as Parasites of Heliothis zea: Development of Methods

Field-cage studies with Trichogramma pretiosum Riley (= T. semifumatum (Perkins)) were initiated to establish a standardized system for future selection of Trichogramma species or races for use in augmentation programs in cotton. Data indicated no preference by parasites for eggs of the bollworm placed on leaves of corn and cotton plants. There was also no preference by the wasps for eggs of H. zea placed on the upper and under surfaces of leaves of the same plants. Parasitization was significantly greater for eggs placed on leaves near the top of the plants than for eggs placed on leaves near the bottom. Eggs were parasitized in significantly greater numbers when placed on white or on green cards with a smooth surface than when placed on black cards with a smooth surface. Hence, future evaluation of Trichogramma stocks will be carried out only by placing host’s eggs on white cards stapled to the under surfaces of leaves near the tops of cotton plants.
Smartphone-Based Wound Assessment System for Patients With Diabetes

Diabetic foot ulcers represent a significant health issue. Currently, clinicians and nurses mainly base their wound assessment on visual examination of wound size and healing status, while the patients themselves seldom have an opportunity to play an active role. Hence, a more quantitative and cost-effective examination method that enables the patients and their caregivers to take a more active role in daily wound care potentially can accelerate wound healing, save travel cost and reduce healthcare expenses. Considering the prevalence of smartphones with a high-resolution digital camera, assessing wounds by analyzing images of chronic foot ulcers is an attractive option. In this paper, we propose a novel wound image analysis system implemented solely on the Android smartphone. The wound image is captured by the camera on the smartphone with the assistance of an image capture box. After that, the smartphone performs wound segmentation by applying the accelerated mean-shift algorithm. Specifically, the outline of the foot is determined based on skin color, and the wound boundary is found using a simple connected region detection method. Within the wound boundary, the healing status is next assessed based on red–yellow–black color evaluation model. Moreover, the healing status is quantitatively assessed, based on trend analysis of time records for a given patient. Experimental results on wound images collected in UMASS—Memorial Health Center Wound Clinic (Worcester, MA) following an Institutional Review Board approved protocol show that our system can be efficiently used to analyze the wound healing status with promising accuracy.
Self-tuning in an outgoing brane wave model

We introduce a new brane-world model in which the bulk solution consists of outgoing plane waves. This is an exact solution to string theory with no naked singularities. The recently discussed self-tuning mechanism to cancel the cosmological constant on a brane is naturally incorporated. We show that even if the vacuum energy on the brane changes, e.g. due to a phase transition, the brane geometry remains insensitive to the local vacuum energy. We also consider the static self-tuning branes introduced earlier, and find a solution in which the brane geometry starts to contract when the vacuum energy on the brane changes.
Transformational Medical Education Leadership: Ethics, Justice and Equity—The U. S. Public Health Service Syphilis Study at Tuskegee Provides Insight for Health Care Reform

The U.S. Public Health Service Syphilis Study at Tuskegee of Untreated Syphilis in the Negro Male ended more than 40 years ago. Yet it is still a significant milestone that focuses our attention on...