cssi/SciSciGPT-SciSciNet huggingface dataset:
Bariatric surgery to achieve transplant in end-stage organ disease patients: A systematic review and meta-analysis.

Abstract Background As obesity prevalence grows, more end-stage organ disease patients will be precluded from transplant. Numerous reports suggest bariatric surgery in end-stage organ disease may help patients achieve weight loss sufficient for transplant listing. Methods We performed a systematic review/meta-analysis of studies of bariatric surgery to achieve solid organ transplant listing. Results Among 82 heart failure patients, 40.2% lost sufficient weight for listing, 29.3% were transplanted, and 8.5% had sufficient improvement with weight loss they no longer required transplantation. Among 28 end-stage lung disease patients, 28.6% lost sufficient weight for listing, 7.1% were transplanted, and 14.3% had sufficient improvement following weight loss they no longer required transplant. Among 41 cirrhosis patients, 58.5% lost sufficient weight for listing, 41.5% were transplanted, and 21.9% had sufficient improvement following weight loss they no longer required transplant. Among 288 end-stage/chronic kidney disease patients, 50.3% lost sufficient weight for listing and 29.5% were transplanted. Conclusions Small sample size and publication bias are limitations; however, bariatric surgery may benefit select end-stage organ disease patients with obesity that precludes transplant candidacy.
Abstract MP02: Sox6 Ablation In Renin Expressing Cells Protects Mice Against Hypertension And Kidney Injury

Introduction: The Renin angiotensin aldosterone system (RAAS) is implicated in renal artery stenosis (RAS) and renovascular hypertension. RAS or renal artery occlusion is an intractable problem aff...
Depression symptoms in adolescents with autism spectrum disorder: A contextual approach to mental health comorbidities.

Abstract Introduction Although research on mental health comorbidities in autism spectrum disorder (ASD) has increased in recent years, little has been done to evaluate potential individual × environment interactions associated with these comorbidities. The current study explored whether ASD-related characteristics (social-communication impairment) and environmental factors (peer and family contexts) had additive or interactive effects on the depression symptoms of youth with ASD. Method In a cross-sectional sample of adolescents with ASD (N = 176; 13–17 years old; 72.7% male), primary caregivers and adolescents responded to a series of surveys online pertaining to adolescents' mental health (Revised Child Anxiety and Depression Scale), family functioning (Self-Report of Family Inventory), and experiences of peer victimization (Peer Experiences Questionnaire-Revised). Results There were statistically significant interactions between social-communication skills and the environment in both family (△R2 = 0.02) and peer (△R2 = 0.02) contexts. For youth with better social-communication skills, there was a positive association between peer victimization and depression symptoms and a negative association between family competence and depression symptoms. Conclusion Findings support social-push interactive models in which better social-communication skills are associated with fewer depression symptoms in the context of less-stressful peer and family environments, highlight the utility of ecologically informed approaches to the mental health of youth with ASD, and suggest several areas for future study.
Dehydrogenative Pd and Ni Catalysis for Total Synthesis.

ConspectusThe development of novel synthetic methods remains a cornerstone in simplifying complex molecule synthesis. Progress in the field of transition metal catalysis has enabled new mechanistic strategies to achieve difficult chemical transformations, increased the value of abundant chemical building blocks, and pushed the boundaries of creative and strategic route design to improve step economy in multistep synthesis. Methodologies to introduce an olefin into saturated molecules continue to be essential transformations because of the plethora of reactions available for alkene functionalization. Of particular importance are dehydrogenation reactions adjacent to electron-withdrawing groups such as carbonyls, which advantageously provide activated olefins that can be regioselectively manipulated. Palladium catalysis occupies a central role in the most widely adopted carbonyl dehydrogenation reactions, but limits to the scope of these protocols persist.In this Account, we describe our group's contributions to the area of transition-metal-catalyzed dehydrogenation using palladium catalysis and more sustainable and economical nickel catalysis. These metals are used in conjunction with allyl and aryl halides or pseudohalides that serve as oxidants to access a unique mechanistic approach for one-step α,β-dehydrogenation of various electron-withdrawing groups, including ketones, esters, nitriles, amides, carboxylic acids, and electron-deficient heteroarenes. The pivotal reaction parameters that can be modified to influence reaction efficiency are highlighted, including base and oxidant structure as well as ligand and salt additive effects. This discussion is expected to serve as a guide for troubleshooting challenging dehydrogenation reactions and provide insight for future reaction development in this area.In addition to enabling dehydrogenation reactions, our group's allyl-Pd and -Ni chemistry can be used for C-C and C-X bond-forming reactions, providing novel disconnections with practical applications for expediting multistep synthesis. These transformations include a telescoped process for ketone α,β-vicinal difunctionalization; an oxidative enone β-functionalization, including β-stannylation, β-silylation, and β-alkylation; and an oxidative cycloalkenylation between unstabilized ketone enolates and unactivated alkenes. These bond-forming methodologies broaden the range of transformations accessible from abundant ketone, enone, and alkene moieties. Both the dehydrogenation and C-C and C-X bond-forming methodologies have been implemented in our group's total synthesis campaigns to provide step-efficient synthetic routes toward diverse natural products.Through the lens of multistep synthesis, the utility and robustness of our dehydrogenation and dehydrogenative functionalization methodologies can be better appreciated, and we hope that this Account will inspire practitioners to apply our methodologies to their own synthetic challenges.
Calling for Social Support: Whose Support and What Types of Support Matter for Early Adolescents’ Life Satisfaction?

Trends in psychological research suggest an increasing interest in indicators of well-being in youth, such as overall life satisfaction (LS). Studies indicate a strong association between LS and social support from different sources within an early adolescent’s social network. However, the unique contributions of specific types of supportive behaviors (within sources of social support) as they relate to development of early adolescent global LS have been largely overlooked. Thus, we examined the unique contributions of sources and types (i.e., emotional, appraisal, informational, instrumental) within three sources of support (i.e., parent, teacher, peer) to global LS in a sample of 1732 middle school students from four schools in a southeastern U.S. state. We also investigated gender as a potential moderator between social support sources and types within sources and LS. After controlling for age and socioeconomic status, multiple regression analyses demonstrated unique differences between social support types within sources for each social support source, apart from appraisal support, which was not found to be statistically significant within any source of support. Notably, no statistically significant interaction was demonstrated between gender and social support source or between gender and social support types within each source of social support. Such findings inform assessments and interventions aimed at improving youth LS.
Characterization and Clinical Significance of EIF1AX Mutations and Co-Mutations in Cytologically Indeterminate Thyroid Nodules: A 5-Year Retrospective Analysis.

Objective . Mutations in the EIF1AX gene have been recently detected in a small percentage of benign and malignant thyroid lesions. We sought to investigate the prevalence and clinical significance of EIF1AX mutations and co-mutations in cytologically indeterminate thyroid nodules at our institution. Materials and Methods . A 5-year retrospective analysis was performed on thyroid nodules with a cytologic diagnosis of Bethesda category III or IV, which had undergone testing by our in-house next generation sequencing panel. Surgically resected nodules with EIF1AX mutations were identified, and mutation type and presence of co-mutations were correlated with histopathologic diagnosis. Results . 41/904 (4.5%) cases overall and 26/229 (11.4%) surgically resected nodules harbored an EIF1AX mutation. The most common histologic diagnoses were follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma. 11/26 (42.3%) of nodules had isolated EIF1AX mutation. Co- mutations were found in RAS (12/26; 46.2%), TERT (5/26; 19.2%) and TP53 (2/26; 7.7%). EIF1AX mutation alone conferred a 36.4% risk of malignancy (ROM) and 54.5% ROM or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), while the ROM was significantly higher in nodules with concurrent RAS (71.4%), TERT, TP53 and RAS+TERT (100%) mutations. Conclusion . EIF1AX mutations occur in benign and malignant follicular thyroid neoplasms. In our cohort, the majority of mutations occurred at the splice acceptor site between exons 5 and 6. Importantly, the coexistence of EIF1AX mutations with other driver pathogenic mutations in RAS, TERT and TP53 conferred a 100% ROM or NIFTP, indicating that such nodules require surgical removal.
Diffusivity Metrics Three Months After Upfront Gamma Knife Radiosurgery for Trigeminal Neuralgia May Be Correlated with Pain Relief.

Background Gamma Knife radiosurgery (GKRS) is a safe and effective treatment option for trigeminal neuralgia (TN). However, there is no objective, noninvasive tool to identify nonresponders or late responders to GKRS and to facilitate longitudinal patient management. We hypothesized that diffusivity metrics obtained 3 months after GKRS may correlate with response to treatment. Methods Sixteen patients with TN treated with GKRS underwent preprocedural and 3-month postprocedural 3-T magnetic resonance imaging of the brain. Diffusion tensor metrics of axial diffusivity, radial diffusivity, and fractional anisotropy were extracted from the pontine segments, the root entry zones, and the distal cisternal segments of both trigeminal nerves. Diffusivity metrics at the 3-month post-GKRS time point were compared with pain relief at last follow-up. Favorable response to GKRS was defined as pain intensity of I-III on the Barrow Neurological Institute scale. Results The median clinical follow-up was 11 months (range 3–18 months). Patients with favorable response to GKRS at last follow-up had lower mean fractional anisotropy values at the pontine segment (P = 0.04) and increased mean radial diffusivity values at the root entry zones (P = 0.032) of the treated trigeminal nerve on the 3-month diffusion tensor imaging sequences as compared with the nonresponders. Conclusions Diffusivity metrics changes on the treated trigeminal nerve at the 3-month time point after GKRS for TN correlated with pain relief at last follow-up. Further, well-designed studies are warranted to establish the clinical application of diffusion tensor imaging as a noninvasive, prognostic tool in patients with TN managed with GKRS.
The Str(AI)ght Scoop: Artificial Intelligence Cues Reduce Perceptions of Hostile Media Bias

In the face of increasing public distrust for journalistic institutions, stories sourced from artificially intelligent (AI) journalists have the potential to lower hostile media bias by activating ...
Tips and Tricks When Performing an Adenomyomectomy

Study Objective To present principles and techniques for safe and efficient laparoscopic surgery during excision of an adenomyoma. Design Stepwise educational demonstration of techniques with narrated video footage. Setting Adenomyomas are not always easily excised and often a surgical plane cannot be easily identified. Similar to myomectomies, an adenomyomectomy may be associated with increased blood loss. In this video, we review key principles and techniques to safely perform a laparoscopic adenomyomectomy. Patients or Participants 33-year-old female with a 9cm uterine mass experiencing menorrhagia and dysmenorrhea. Interventions The key principles for safe and effective laparoscopic adenomyomectomy include: - Preoperative administration of Misoprostol - Instillation of Vasopressin in planned incision line - Intraoperative use of tranexamic acid - Performing a uterine artery ligation - Knowledge of anatomical landmarks - Performing a careful dissection - Uterine instillation of methylene blue - Appropriate instrument use Measurements and Main Results The patient recovered well without any postoperative complications. Conclusion Adenomyoma excision can be safely performed if one understands appropriate surgical techniques and solutions to improve surgical outcomes.
Factor Structure and Validity of the Body Parts Satisfaction Scale: Results from the 1972 Psychology Today Survey

In 1972, the first major national study on body image was conducted under the auspices of Psychology Today. Body image was assessed with the Body Parts Satisfaction Scale, which examined the dissatisfaction people experienced with 24 aspects of their bodies. Despite the continued reliance on this scale and reference to the study, data on the factor structure of this measure in a sample of adults have never been published, and citations of the original scale have relied on an unpublished manuscript (Bohrnstedt, 1977). An exploratory factor analysis conducted on 2,013 adults revealed factors for men (Face, Sex Organ, Height, Lower Body, Mid Torso, Upper Torso, Height) and women (Face, Sex Organ, Height, Lower Torso, Mid Torso, Extremities, Breast). The factors were weakly to moderately intercorrelated, suggesting the scale can be analyzed by items, by subscales, or by total score. People who reported more dissatisfaction with their body also tended to report lower self-esteem and less comfort interacting with members of the other sex. The analyses provide a useful comparison point for researchers looking to examine gender differences in dissatisfaction with specific aspects of the body, as well as the factor structures linking these items.
The Art and Science of Systems Engineering

The National Aeronautics and Space Administration (NASA) was established in 1958, and its Marshall Space Flight Center was founded in 1960, as space-related work was transferred from the Army Ballistic Missile Agency at Redstone Arsenal, where Marshall is located. With this heritage, Marshall contributes almost 50 years of systems engineering experience with human-rated launch vehicles and scientific spacecraft to fulfill NASA's mission exploration and discovery. These complex, highly specialized systems have provided vital platforms for expanding the knowledge base about Earth, the solar system, and cosmos; developing new technologies that also benefit life on Earth; and opening new frontiers for America's strategic space goals. From Mercury and Gemini, to Apollo and the Space Shuttle, Marshall's systems engineering expertise is an unsurpassed foundational competency for NASA and the nation. Current assignments comprise managing Space Shuttle Propulsion systems; developing environmental control and life support systems and coordinating science operations on the International Space Station; and a number of exploration-related responsibilities. These include managing and performing science missions, such as the Lunar Crater Observation and Sensing Satellite and the Lunar Reconnaissance Orbiter slated to launch for the Moon in April 2009, to developing the Ares I crew launch vehicle upper stage and integrating the vehicle stack in house, as well as designing the Ares V cargo launch vehicle and contributing to the development of the Altair Lunar Lander and an International Lunar Network with communications nodes and other infrastructure.
Indicaciones médicas y quirúrgicas de los potenciales evocados

Evoked potentials (EP) are more sensitive than specific, safe, objective and reproducible neurophysiologic techniques to assess integrity of peripheral and central sensory and motor pathways. The integrity of pathways are determined by measurement the latency of the recorded and digitally averaged electrical events elicited after adequate stimulation. EP are medically and surgically recommended in conditions in which the diagnoses, determination of neurological outcome in comatose and under anesthesia patients, and determination of the course and evaluation of treatment are uncertain with neurologic examination and other neurodiagnostic studies.
A tube-MOT of cesium atoms for loading microstructures

Summary form only given. The magneto-optical trap (MOT) has become the workhorse for many, if not most atom-optics experiments. The traditional MOT uses a pair of coils in anti-Helmholtz configuration to generate a quadrupole field with a typical gradient in the order of 10 Gauss/cm and a typical MOT diameter of 1 mm. In this paper we describe the formation of a surface MOT in a skewed magnetic field, produced by a magnetic laminate.We have imaged the fluorescence of the trapped cloud onto a CCD camera, and made cross sections of the trapped atom cloud.
Thermal Conductivity of Isotopic Mixtures of Solid Helium

This paper reports thermal-conductivity measurements in isotopic mixtures of solid helium at concentrations of 1%, 4%, 10%, and 50% of ${\mathrm{He}}^{3}$ in ${\mathrm{He}}^{4}$ and vice versa. The data were taken at $V=19.5$ ${\mathrm{cm}}^{3}$/mole and $V=20.2$ ${\mathrm{cm}}^{3}$/mole; the data at 19.5 ${\mathrm{cm}}^{3}$/mole are analyzed using the phenomenological equation of Callaway. Resistance to heat flow is assumed to be due to boundary scattering, normal-process scattering, umklapp-process scattering, and a Rayleigh-like scattering mechanism which may be a combination of mass-fluctuation scattering and lattice-distortion scattering. The strength of these scattering mechanisms is determined by the analysis. The major contribution to the thermal resistance at low temperature is found to be the lattice distortion around the site of an isotopic impurity. The intrinsic strength of lattice-distortion scattering is evaluated and found to depend on concentration more strongly than the $x(1\ensuremath{-}x)$ expected by analogy to mass-fluctuation scattering. Two arguments are given in explanation of this increased concentration dependence.
A Novel Way of Manipulating and Optimizing CAM Profiles for Internal Combustion Engines

Generating an optimum cam profile for an internal combustion engine application is usually a very involved process. This is because of the challenge faced by the engine engineers to perform several trade-offs between fuel economy, performance, durability and emissions. Typically, the trade offs are worked out using several computer codes and with the involvement of a cross-functional team of engineers. Hence, there is a need to develop a tool that can encapsulate the various computer codes and can manipulate the cam profile with ease. With the existence of such an automated tool, optimization of the cam profile can be achieved with a specified trade-off between the several metrics identified above. This paper describes the development of such a tool, and discusses the ingredients that make it flexible and computationally efficient. Results from the use of this tool are documented in this paper as well.Copyright © 2007 by ASME
Peracute and acute death from ischaemic heart disease within 4 days of onset of symptoms.

Summary Post-mortem examination was made of 136 patients who died of ischaemic heart disease from within a few minutes to 4 days after the onset of symptoms. Acute myocardial infarction was detected by means of the histochemistry of dehydrogenases in 102 cases (75%); in 34 cases (25%) no infarction was found, but the presence of coronary obstruction together with clinical symptoms justified the diagnosis of acute coronary insufficiency. Fifty-six of the infarctions occurred within 2–3 h after the onset of ischaemia, 24 within 4–5 h, 12 within 6–24 h, and 10 within 1–4 days. The chances of recovery increased if the patients survived for 24 h. The period of 5 h after the onset of ischaemia appeared especially important; 80 of 102 patients with acute myocardial infarction died during that period. Thirty-one of 34 patients with acute coronary insufficiency and 60 of 102 patients with acute myocardial infarction died peracutely, i.e. within a few minutes to 2 h after the onset of symptoms. In the patients of the latter group the onset of symptoms must have been delayed, otherwise none of these patients could have appeared in the category of peracute death. This delay was more obvious in the patients with acute myocardial infarction localized in the area supplied by the left descending artery. The occurrence of peracute deaths could not be correlated with a particular localization of area of infarction. The causes of coronary obstructions and the role of dynamic disturbances of coronary perfusion in the pathogenesis of coronary insufficiency and myocardial infarction are discussed.
Use of Vacuum Tubes in Measurements

For the benefit of those who may wish to use vacuum tubes in meeting specific problems in the field of measurement, the comprehensive bibliography contained in this paper has been prepared. Some 600 references are included in this list, selected from a total of about 1,500 papers or books published since approximately 1920. The first portion of the bibliography contains publications dealing with the characteristics of vacuum tubes, and the second portion contains references to specific applications to measurement problems.
Status of the National Ignition Facility project

The ultimate goal of worldwide research in inertial confinement fusion (ICF) is to develop fusion as an inexhaustible, economic, environmentally safe source of electric power. Following nearly thirty years of laboratory and underground fusion experiments, the next step toward this goal is to demonstrate ignition and propagating burn of fusion fuel in the laboratory. The National Ignition Facility(NIF) Project is being constructed at Lawrence Livermore National Laboratory (LLNL), for just this purpose. NIF will use advanced Nd-glass laser technology to deliver 1.8 MJ of 0.35-um laser light in a shaped pulse, several nanoseconds in duration, achieving a peak power of 500 TW. A national community of U.S. laboratories is participating in this project, now in its final design phase. Franceand the United Kingdom are collaborating on development of required technology under bilateral agreements with the US. This paper presents thestatus of the laser design and development of its principal components and optical elements.
The Effect of Hyperventilation on the Normal Adult Electrocardiogram

The effect of brief hyperventilation on the precordial T waves of 350 normal adults is described. Evidence is presented that brief hyperventilation initiates a vagal reflex which results in the T-wave inversion. Supportive data are also given to exclude respiratory alkalosis as a possible mechanism. Caution is advised in interpreting isolated T-wave inversions as indicative of organic heart disease. It is proposed that isolated T-wave inversion be deleted as a criterion for a "positive" exercise test.
Three-Dimensional Digital Planes

Definitions of 3-D digital surface and plane are introduced. Many geometric properties of these objects are examined. In particular, it is shown that digital convexity is neither a necessary nor a sufficient condition for a digital surface element to be a convex digital plane element, but it is both necessary and sufficient for a digital surface to be a digital plane. Also algorithms are presented to determine whether or not a finite set of digital points is a (convex) digital plane element.
Amiodarone Skin Toxicity

Bluish-grey discoloration of the face after 1 year of treatment with amiodarone in a 54-year-old man with a history of ventricular tachycardia (left). …
Altered ventilatory and thermoregulatory control in male and female adult Pet-1 null mice.

The integrity of the serotonin (5-HT) system is essential to normal respiratory and thermoregulatory control. Male and female transgenic mice lacking central 5-HT neurons (Lmx1b(f/f/p) mice) show a 50% reduction in the hypercapnic ventilatory response and insufficient heat generation when cooled (Hodges and Richerson, 2008a; Hodges et al., 2008b). Lmx1b(f/f/p) mice also show reduced body temperatures (T(body)) and O(2) consumption [Formula: see text] , and breathe less at rest and during hypoxia and hypercapnia when measured below thermoneutrality (24 °C), suggesting a role for 5-HT neurons in integrating ventilatory, thermal and metabolic control. Here, the hypothesis that Pet-1 null mice, which retain 30% of central 5-HT neurons, will demonstrate similar deficits in temperature and ventilatory control was tested. Pet-1 null mice had fewer medullary tryptophan hydroxylase-immunoreactive (TPH(+)) neurons compared to wild type (WT) mice, particularly in the midline raphe. Female (but not male) Pet-1 null mice had lower baseline ventilation (V(E)), breathing frequency (f), [Formula: see text] and T(body) relative to female WT mice (P < 0.05). In addition, V(E) and [Formula: see text] were decreased in male and female Pet-1 null mice during hypoxia and hypercapnia (P < 0.05), but only male Pet-1 null mice showed a significant deficit in the hypercapnic ventilatory response when expressed as % of control (P < 0.05). Finally, male and female Pet-1 null mice showed significant decreases in T(body) when externally cooled to 4 °C. These data demonstrate that a moderate loss of 5-HT neurons leads to a modest attenuation of mechanisms defending body temperature, and that there are gender differences in the contributions of 5-HT neurons to ventilatory and thermoregulatory control.
Merchant shipping in the service of the navy board: The chartering of storeships, 1739-48

The War of Austrian Succession marked the first time a large number of British warships served in the Mediterranean and West Indies. To supply them, the Royal Navy used merchant ships to carry naval stores. The vessels were hired on short-term space charters. These agreements stipulated that the ships would be inspected by government officials, that they would sail in convoy, and that demurrage would be paid in the event of delay. Shipowners found the terms attractive enough for the navy to have little difficulty hiring vessels in the London market. Almost 100 merchantmen were chartered during the war, but the significance of the practice was less economic than strategic. For 200 years it would enable Britain to exercise sea power in distant waters.
Shear and Pearse Method for Direct Histochemical Demonstration of Sialic Acid

A DIRECT histochemical method for the demonstration of sialic acid was recently published by Shear and Pearse1 which is based on a method described by Svennerholm2. The procedure as described by Shear and Pearse requires that the reaction be carried out on fresh-frozen cryostat sections (8µ), mounted on albumin-coated glass slides which have been exposed to formaldehyde vapour in a closed desiccator for at least 72 h and washed in running water for 2 min and allowed to dry. The reaction is then carried out by covering the sections with a few drops of resorcinol hydrochloride. After 2 min, excess reagent is removed and the sections treated with a few drops of 1 per cent sodium nitrite in concentrated hydrochloric acid. The red colour which develops is attributed to sialic acid sites and the intensity proportioned to the sialic acid concentration.
Role of inflectional regularity and semantic transparency in reading morphologically complex words: evidence from acquired dyslexia.

We report two patients with acquired phonological dyslexia who have great difficulty reading affixed words. Experiment 1 demonstrates that both patients' reading performance is influenced by the apparent morphological status of words by comparing the patients' reading of suffixed and pseudo-suffixed words. Experiment 2 was designed to examine reading performance of both regularly and irregularly inflected words. Experiment 3 examines the patients' reading of derivational forms with particular emphasis of the role of ‘semantic transparency’. Experiment 4 tested both patients' reading of prefixed words. Finally, Experiment 5 examined performance on a lexical decision task using affixed words. These data support models in which regularly formed inflections and semantically transparent derived forms are subjected to decomposition during processing, whereas irregularly inflected forms and semantically opaque forms may be represented independently. Data are discussed with regard to current ‘dual mechanism’ mode...
Mechanix: A Sketch-Based Educational Interface

At the university level, high enrollment numbers in classes can be overwhelming for professors and teaching assistants to manage. Grading assignments and tests for hundreds of students is time consuming and has led towards a push for software-based learning in large university classes. Unfortunately, traditional quantitative question-and-answer mechanisms are often not sufficient for STEM courses, where there is a focus on problem-solving techniques over finding the "right" answers. Working through problems by hand can be important in memory retention, so in order for software learning systems to be effective in STEM courses, they should be able to intelligently understand students' sketches. Mechanix is a sketch-based system that allows students to step through problems designed by their instructors with personalized feedback and optimized interface controls. Optimizations like color-coding, menu bar simplification, and tool consolidation are recent improvements in Mechanix that further the aim to engage and motivate students in learning.
Some aspects of diagrammatic perturbation theory

Many-body perturbation theory, or the linked cluster diagrammatic representation of Rayleigh-Schrodinger perturbation theory, is demonstrated to arise from the variational configuration interaction procedure by elementary considerations of Lowdin's partitioning approach to perturbation theory. As a consequence, variational upper bounds to the energy, which arise from the inclusion of some “unlinked” terms, may be obtained from odd-order MBPT calculations and are useful for certain applications. A brief discussion of low-order correlation diagrams for second-order properties is also presented.
Phosphorus Dynamics in Broiler Litter-Amended Soils

Abstract Because land application of broiler litter is commonly made in the spring before cropping season and in the fall, it is essential to understand how environmental variations, such as temperature, affect the phosphorus (P) dynamics. A laboratory incubation study was conducted at Waste Management and Forage Research Unit, USDA‐ARS with the objective of determining the effects of temperature and soil properties on water‐soluble P (WSP), Mehlich 3 P, and P fractions in broiler litter‐amended soils. Broiler litter was mixed with three soils (Leeper silty clay, Grenada silt loam, and Ruston sandy loam) at the rate of 10 Mg ha−1. The mixtures were incubated at 18°C, 25°C, and 32°C for up to 90 days and repeated three times. Soil samples were taken at eight time intervals (2, 5, 10, 15, 30, 60, and 90 days) and analyzed for water‐soluble P and Mehlich 3‐extractable P (MEP). Phosphorus also was fractionated chemically into inorganic and organic components by sequential extraction for soil samples taken at ...
Use of Laser Radiation in the Calibration of Spectrometer Scanning Functions

The dependence of the spectrometer scanning function on the spatial coherence of the illumination at the entrance slit implies that the spatial coherence of laser radiation must be degraded before its narrow spectral bandwith can be used to advantage in scanning-function calibration. A conventional incoherent source can be simulated by using a source having a relatively large correlation interval, provided that its correlation function has a favorable form. Partial-coherence theory is used to obtain conditions on the correlation function resulting from the properties of Globar radiation. The correlation function at a spectrometer entrance slit is experimentally determined using a method described by Beran and Parrent. The results for an incoherent Hg source are in agreement with Hopkins’s concept of an effective source. Results using laser light reflected from an integrating sphere indicate that such a source may be used interchangeably with an ordinary incoherent source for scanning-function calibration.
Mechanistic Studies on the Reaction of Fischer Carbene Complex with Alkynes: Does the Alkyne Insertion Intermediate Form Irreversibly?

The regioselectivity of the formation of three different products from the reaction of 1-phenylpropyne with (methoxy)(2-methoxyl-1-phenyl)methylene pentacarbonyl chromium 12 was examined in detail. The phenol product is formed with a substantial regioselectivity which is temperature-dependent, but the indene products (obtained as two compounds: indene and indenone) are formed as a nearly equal mixture of regioisomers. The proportion of indene and phenol products is dependent on the concentration with greater amounts of phenol products being formed at higher concentrations. The total regioselectivity of all of the products is also a function of the concentration. This result could be due either to an equilibration of the η1,η3-vinyl carbene intermediates in this reaction or to a change in mechanisms in the formation of the η1,η3-vinyl carbene intermediates from one involving a dissociative incorporation of the alkyne to one involving an associative incorporation of the alkyne. Kinetic studies reveal that ...
Vaginal infections in human immunodeficiency virus-infected women.

Abstract Objective: This study was undertaken to compare the frequencies of vaginal infections among human immunodeficiency virus–infected women with those among human immunodeficiency virus–seronegative women. Study Design: Human immunodeficiency virus–seropositive women attending a comprehensive care center for human immunodeficiency virus disease at the outpatient department of an inner-city hospital in Houston underwent rigorous gynecologic evaluation for sexually transmitted diseases, including evidence of vaginal infections such as bacterial vaginosis, vulvovaginal candidiasis, and trichomonal vaginitis. Demographic information was collected, as was information regarding disease classification and degree of immunosuppression. Data regarding sexually transmitted diseases, data regarding vaginal infections, and demographic information were collected from a cohort of human immunodeficiency virus–seronegative women attending a sexually transmitted disease and family planning clinic at the same institution. The two groups were compared to determine whether there were any differences between them in the frequencies of sexually transmitted diseases and vaginal infection. Data analysis used the t test for parametric data and the Fisher exact test for nonparametric data where appropriate. P Results: There was no difference in age between the 2 groups. The human immunodeficiency virus–infected group was predominantly African American (80.5%), whereas the human immunodeficiency virus–seronegative control group was more evenly divided between African American women (45.8%) and Latinos (41.7%; P P =.02), vulvovaginal candidiasis ( P =.001), and trichomonal vaginitis ( P =.003). Conclusion: Human immunodeficiency virus–infected women had increased frequencies of vaginal infections, including bacterial vaginosis, vulvovaginal candidiasis, and trichomonal vaginitis, with respect to human immunodeficiency virus–seronegative control subjects. No differences between the 2 groups were seen in the frequencies of sexually transmitted diseases. (Am J Obstet Gynecol 2000;183:347-55.)
Auroral ion outflow: low altitude energization

Abstract. The SIERRA nightside auroral sounding rocket made observations of the origins of ion upflow, at topside F-region altitudes (below 700 km), comparatively large topside plasma densities (above 20 000/cc), and low energies (10 eV). Upflowing ions with bulk velocities up to 2 km/s are seen in conjunction with the poleward edge of a nightside substorm arc. The upflow is limited within the poleward edge to a region (a) of northward convection, (b) where Alfvenic and Pedersen conductivities are well-matched, leading to good ionospheric transmission of Alfvenic power, and (c) of soft electron precipitation (below 100 eV). Models of the effect of the soft precipitation show strong increases in electron temperature, increasing the scale height and initiating ion upflow. Throughout the entire poleward edge, precipitation of moderate-energy (100s of eV) protons and oxygen is also observed. This ion precipitation is interpreted as reflection from a higher-altitude, time-varying field-aligned potential of upgoing transversely heated ion conics seeded by the low altitude upflow.
Characterization of carbons derived from cellulose and lignin and their oxidative behavior.

Abstract In this study the oxidative behavior of carbons derived from cellulose and lignin were compared using thermogravimetric analysis (TGA). Specific surface area and chemical composition of the two types of carbon were analyzed using nitrogen adsorption at 77 K and infrared spectroscopy respectively. The results demonstrate that cellulose carbon has a higher reaction order and lower activation energy than lignin carbon under identical experimental conditions when they were prepared at temperatures lower than 500 °C. However, such differences were considerably reduced for the carbon samples prepared at temperatures greater than 700 °C. It was verified that lignin carbon is more stable than cellulose carbon due to its higher content of aromatic structures when they are prepared at lower temperature. The specific surface area and porosity have a more limited contribution to the differential oxidative behaviors of the two types of carbon. This research has significance related to the formation of carbon nanotubes from plant materials during low temperature carbonization.
The Revealed Preference Theory of Changing Tastes

We analyse preferences over finite decision problems in order to model decision-makers with “changing tastes”. We provide conditions on these preferences that identify the Strotz model of consistent planning. Building on an example given by Peleg and Yaari (1973), we show that for problems with infinitely many choices, Strotz’s representation of preferences may not be well defined. For that case, we propose a well-defined approximation which is empirically indistinguishable from the Strotz preference that is being approximated.
Molecular Requirements for the Action of 2-APB on STIM1-Orai1 Coupling

Store-operated Ca2+ entry (SOCe) triggered by the depletion of endoplasmic reticulum (ER) luminal Ca2+ stores is a major Ca2+ entry pathway in non-excitable cells and is essential in physiological Ca2+ signaling and homeostasis. STIM proteins are sensors of ER luminal Ca2+, which translocate to ER-plasma membrane (PM) junctional regions to activate the family of Orai channels mediating Ca2+ entry. To dissect the mechanisms by which of 2-amino-ethoxydiphenyl borate (2-APB), modifies SOCe, the effect of 2-APB on the coupling between Orai1 and various STIM1 fragments were examined with imaging and whole-cell patch clamp methods. We demonstrate that 50 μM 2-APB induces coupling between C-terminus fragments of STIM1 (STIM1ct) and Orai1, in a reversible and Ca2+-independent manner. Although the STIM1-Orai1 Activation Region (SOAR) is already tightly bound with Orai1, 50 μM 2-APB can still induce an increase in FRET, Ca2+ influx and ICRAC activation, therefore, 2-APB increases SOCe by enhancing the coupling between SOAR and Orai1. In contrast, the inhibition of SOCe by 2-APB is not accompanied by a decrease in STIM1-, or SOAR-Orai1 FRET, or dissociation of SOAR from Orai channels. This indicates that the inhibitory effect of 2-APB on Orai1 is due to conformational changes within the SOAR-Orai1 complex that leads to blockage of the Orai1 channels while the two proteins remain associated. This conformational changes appear to come from the gating and selectivity filter of Orai1, as STIM1- or SOAR-Orai1V102C mediated Ca2+ influx is no longer inhibited by 50 μM 2-APB. In summary, our results indicated that 2-APB first enhances the coupling between SOAR-Orai1, resulting in an increase in SOCe; then 2-APB modifies the pore of Orai1 around V102 and inhibits SOCe.
Segmental and secondary dynamics in hydrogen-bonded poly(4-vinylphenol)/poly(methyl methacrylate) blends

Broadband dielectric spectroscopy was used to study the segmental (α) and secondary (β) relaxations in hydrogen-bonded poly(4-vinylphenol)/poly(methyl methacrylate) (PVPh/PMMA) blends with PVPh concentrations of 20–80% and at temperatures from −30 to approximately glass-transition temperature (Tg) + 80 °C. Miscible blends were obtained by solution casting from methyl ethyl ketone solution, as confirmed by single differential scanning calorimetry Tg and single segmental relaxation process for each blend. The β relaxation of PMMA maintains similar characteristics in blends with PVPh, compared with neat PMMA. Its relaxation time and activation energy are nearly the same in all blends. Furthermore, the dielectric relaxation strength of PMMA β process in the blends is proportional to the concentration of PMMA, suggesting that blending and intermolecular hydrogen bonding do not modify the local intramolecular motion. The α process, however, represents the segmental motions of both components and becomes slower with increasing PVPh concentration because of the higher Tg. This leads to well-defined α and β relaxations in the blends above the corresponding Tg, which cannot be reliably resolved in neat PMMA without ambiguous curve deconvolution. The PMMA β process still follows an Arrhenius temperature dependence above Tg, but with an activation energy larger than that observed below Tg because of increased relaxation amplitude. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3405–3415, 2004
Thomas hodgkin remembered

Abstract This article is an edited transcript of a talk given at the symposium celebrating the bicentenary of the birth of Thomas Hodgkin, Guy’s Hospital, 2 October 1998.
The uniqueness of humic substances in each of soil, stream and marine environments

Abstract Definitive compositional differences are shown to exist for both fulvic acids and humic acids from soil, stream and marine environments by five different methods (1H and 13C NMR spectroscopy, 14C age and δ13C isotopic analyses, amino acid analyses and pyrolysis-mass spectrometry). Definitive differences are also found between fulvic acids and humic acids within each environment. These differences among humic substances from various sources are more readily discerned because the method employed for the isolation of humic substances from all environments excludes most of the non-humic components and results in more purified humic isolates from water and soils. The major compositional aspects of fulvic acids and humic acids which determine the observed characteristic differences in each environment are the amounts and composition of saccharide, phenolic, methoxyl, aromatic, hydrocarbon, amino acids and nitrogen moieties.
Digital data networks design using genetic algorithms

Abstract Communication networks have witnessed significant growth in the last decade due to the dramatic growth in the use of Internet. The reliability and service quality requirements of modern data communication networks and the large investments in communications infrastructure have made it critical to design optimized networks that meet the performance parameters. Digital Data Service (DDS) is a popular communication service that provides users with a digital connection. The design of a DDS network is a special case of the classic Steiner-tree problem of finding the minimum cost tree connecting a set of nodes, using Steiner nodes. Since it is a combinatorial optimization problem several heuristic algorithms have been developed including Tabu search, and branch and cut algorithm. In this paper, a new approach using genetic algorithms (GAs) is proposed to solve the problem. The results from GA are compared with the Tabu search method. The results indicate that GA performs as well as Tabu search in terms of solution quality but has lower computation time. However, reducing the number of iterations in Tabu search makes it faster than GA and comparable in solution quality with GA.
Mapping Molecular Orientation by Solid-State NMR Imaging

Abstract A new solid-state NMR imaging experiment is presented which provides high-resolution chemical-shift selective images of abundant nuclei. This experiment employs the line-narrowing effects of the TREV-8 pulse sequence and a constant-time phase-encoding period to achieve spatial resolution. At the end of the phase-encoding period, however, the chemical-shift evolution is reversed and an echo is recorded during the subsequent acquisition period. A 3D data set is acquired which, after processing, results in one 2D image for each point in the chemical-shift spectrum. A single vector passing through all of the images provides a dipolar-decoupled NMR spectrum for any picture element in the image. This method has been applied to monitor the propagation of stress during crack growth in polytetrafluoroethylene.
Emergency treatment options for pediatric traumatic brain injury

Traumatic brain injury is a leading killer of children and is a major public health problem around the world. Using general principles of neurocritical care, various treatment strategies have been developed to attempt to restore homeostasis to the brain and allow brain healing, including mechanical factors, cerebrospinal fluid diversion, hyperventilation, hyperosmolar therapies, barbiturates and hypothermia. Careful application of these therapies, normally in a step-wise fashion as intracranial injuries evolve, is necessary in order to attain maximal neurological outcome for these children. It is hopeful that new therapies, such as early hypothermia or others currently in preclinical trials, will ultimately improve outcome and quality of life for children after traumatic brain injury.
Land use changes affect extreme temperatures

Days with extreme hot and cold temperatures—the extremes that tend to be associated with serious socioeconomic consequences—are predicted to occur more often as Earth's climate changes due to human activity. These changes in extreme temperature days are affected by anthropogenic forcings, including greenhouse gas emission as well as land use change. The land use change effects on temperature extremes have been less well studied. Changes such as clearing forests for grassland can alter the climate through changing reflectivity (albedo) of the surface, through hydrological effects, and through changes in carbon dioxide emission or uptake.