cssi/SciSciGPT-SciSciNet huggingface dataset:
A Review of Residential-Scale Natural Gas-Powered Micro-Combined Heat and Power Engine Systems

A combined heat and power (CHP) system typically employs a prime mover generator that produces electricity on-site and utilizes waste heat energy to supplement a site’s thermal load requirements. Micro-CHP, notionally defined as CHP systems with a capacity lower than 50 kW, offers an alternative, and in some cases a complementary, solution to centralized power generation. A micro-CHP system would be typically installed at a residential or small commercial site where it would consume fuel such as diesel or natural gas to generate electricity locally and further use the rejected waste heat for local heating, air-conditioning, and/or humidification needs. This is in contrast to the rejected heat being dissipated at centralized power plants using cooling towers. The combined efficiency of primary energy usage for such systems can be higher than 90% on a fuel lower heating value (LHV) basis. Since a large fraction of the electricity generated from all the centralized power plants is consumed by the residential and commercial sectors, CHP implementation in these sectors can have a huge impact on both energy savings and carbon dioxide (CO2) emissions’ reduction. Apart from these benefits, decentralized CHP as a form of distributed electricity generation offers numerous advantages such as reduced electrical grid stress, reduced electricity transmission and distribution losses, and potentially improved resiliency of the electricity grid. Various technologies including reciprocating internal combustion engines, Stirling engines, Brayton cycle engines, Rankine cycle engines, fuel cells, and solid-state devices such as thermoelectric generators and thermionic generators can be used as micro-CHP systems. This chapter provides a detailed technological review of engine-based micro-CHP systems and further presents the challenges and opportunities for achieving high fuel conversion efficiency.
Proxy-equation paradigm: A strategy for massively parallel asynchronous computations.

Massively parallel simulations of transport equation systems call for a paradigm change in algorithm development to achieve efficient scalability. Traditional approaches require time synchronization of processing elements (PEs), which severely restricts scalability. Relaxing synchronization requirement introduces error and slows down convergence. In this paper, we propose and develop a novel ``proxy equation'' concept for a general transport equation that (i) tolerates asynchrony with minimal added error, (ii) preserves convergence order and thus, (iii) expected to scale efficiently on massively parallel machines. The central idea is to modify a priori the transport equation at the PE boundaries to offset asynchrony errors. Proof-of-concept computations are performed using a one-dimensional advection (convection) diffusion equation. The results demonstrate the promise and advantages of the present strategy.
Modelling the Processes of Hydraulic Commutation in an Electro-Hydraulic Pumping Unit Driven by an Asynchronous Motor

A mathematical model is presented, describing the small dynamic changes in the operating parameters of the electro-hydraulic pumping unit around an average steady state value. These forced fluctuations are caused by the commutation processes, which equalize the pressure in the working chambers of displacement type hydraulic machine. A block diagram is derived and dynamic structure analysis is conducted. The time and frequency response of the dynamic model are examined numerically, based on experimental data.
The incidence, predictors, and survival of disappearing small renal masses on active surveillance.

Abstract Objective To evaluate the incidence, predictors, and survival for those small renal masses (SRM, solid mass ≤4 cm suspicious for a clinical T1a renal cell carcinoma) that disappear on imaging while undergoing active surveillance (AS). Subjects/patients and methods The Delayed Intervention and Surveillance for SRM registry prospectively enrolled 739 patients with SRMs. Patients having at least 1 image showing no lesion were considered to have a “disappearing” SRM. Logistic regression assessed predictors of having a disappearing SRM and Kaplan-Meier estimates illustrated relative survival. Results Of 374 patients enrolled in AS, 22 (5.9%) experienced a disappearing SRM. Mean time to tumor disappearance was 2.0 years (SD = 1.9) and 50.0% reappeared on subsequent CT imaging. SRM disappearance, most commonly encountered on ultrasound imaging surveillance, was independently associated with tumors Conclusions Approximately 5% of SRM on AS will disappear during follow-up on surveillance imaging. Most of these represent artifacts of heterogeneous imaging modalities, including ultrasound, and the SRM will reappear on subsequent imaging. Given the indolent nature of these lesions, disappearance events do not require reflex repeat imaging and patients should continue AS with their original surveillance schedule intact. A smaller percentage of patients undergoing AS for a SRM may have a mass the permanently disappears.
Comparison of Referral Pathways in Otolaryngology at a Public Versus Private Academic Center

Objective:Delayed medical care may be costly and dangerous. Examining referral pathways may provide insight into ways to reduce delays in care. We sought to compare time between initial referral an...
Generation of a syngeneic orthotopic transplant model of prostate cancer metastasis

Progression to metastatic disease is the primary cause of mortality in men with prostate cancer (PCa). Mouse models which progress with spontaneous metastasis are limited. Such models would allow for extensive studies of molecular mechanisms of metastasis, and more definite pre- clinical therapy trials. Orthotopic murine models have been described; however a limiting biology of these models is their lack of an intact immune system. Within, we describe the development of an androgen sensitive and castrate resistant tractable orthotopic murine syngeneic (immune competent) model of prostate cancer. Both models develop primary tumors which spontaneously progress to metastatic disease in lymph tissue. These models will allow for more complete mechanistic and therapeutic studies in a short time period.
Bidirectional Text-to-Model Element Requirement Transformation

Elicitation, representation, and analysis of requirements are important tasks performed early in the systems engineering process. This remains true with the adoption of Model-Based Systems Engineering (MBSE) methodologies. Existing SysML-based methodologies often choose between (i) using external requirements documents and/or databases as the authoritative source for requirements truth versus (ii) generating requirements directly, as elements in the system model. In either case, there is often need for the systems engineer to manually develop a model-based requirements representation, as this faculty is not automatic in the commonly-used SysML feature set. Additionally, once the system model has been completed, systems engineers typically must prepare traditional “shall-statement” requirements for external review purposes, as not all stakeholders can be expected to be trained in system model interpretation. This paper details a novel effort to address both problems, by automatically transforming text-based requirements (TBR) into SysML model-based requirement (MBR) representations, and vice versa. The text-to-model based transformation direction uses requirement templates and natural language processing techniques, expanding on work from the field of requirements engineering. This paper also presents an aerospace-domain case study application of the developed tool. In the case study, a selected set of requirements were analyzed, and a system model was constructed. Then, the intermediate output system model was updated with additional elements, to represent the progression of the project's systems engineering process. The modified system model was then analyzed, constructing text-based requirements from the structure. The resulting text-based requirements were compared to the initial set of input requirements to assess consistency in both directions of analysis. The methodology developed in this paper improves the systems engineering process by saving the systems engineer time constructing potentially repetitive model elements, and by enabling model-based requirement analyses to methodologies previously only capable of processing text-based requirements. Further, the methodology eases the responsibility of the systems engineer to maintain a copy of the model-based requirements in text-based format.
Use of spironolactone to treat acne in adolescent females.

Background/objectives Studies assessing the utility of spironolactone for treating acne in adolescent females are lacking. Thus, we sought to examine spironolactone's role in treating this patient population. Methods A retrospective review was performed to determine the efficacy of spironolactone treatment in adolescent females seen at Mayo Clinic in Rochester, Minnesota, from 2007 to 2017. Results In a cohort of 80 pediatric patients with a median age of 19 years (range, 14-20 years), 64 patients (80%) experienced improvement of acne on treatment with spironolactone (median dose, 100 mg daily) with a favorable side effect profile. Approximately a quarter of patients (22.5%) had a complete response; more than half (58.8%) had a complete response or a partial response greater than 50%. Initial and maximal responses were observed at a median of 3 months and 5 months, respectively. Patients received treatment with spironolactone for a median duration of 7 months (range, 3-45 months) with limited side effects. Conclusions Spironolactone demonstrated efficacy in treating acne in adolescent females and is a safe long-term alternative to systemic antibiotics in these patients.
Quantum Convolutional Neural Networks for High Energy Physics Data Analysis.

This work presents a quantum convolutional neural network (QCNN) for the classification of high energy physics events. The proposed model is tested using a simulated dataset from the Deep Underground Neutrino Experiment. The proposed architecture demonstrates the quantum advantage of learning faster than the classical convolutional neural networks (CNNs) under a similar number of parameters. In addition to faster convergence, the QCNN achieves greater test accuracy compared to CNNs. Based on experimental results, it is a promising direction to study the application of QCNN and other quantum machine learning models in high energy physics and additional scientific fields.
Wind turbine blade material in the United States: Quantities, costs, and end-of-life options

Abstract Wind energy has experienced enormous growth in the past few decades; as a result, there are thousands of wind turbines around the world that will reach the end of their design lifetimes in the coming years. Much of the material in those turbines can be recycled using conventional processes, but the composite material that is the main component of the blades is more challenging to recycle. In the United States, turbine blades may be disposed of in landfills, adding a new solid waste stream to the material already being landfilled. This paper presents a spatially resolved estimate of the mass and volume of wind turbine blade waste in each state by 2050 and compares these amounts to estimates of the remaining landfill capacity by state. We estimate costs for each stage of the disposal process to indicate cost levels for alternatives. Assuming a 20-year turbine lifetime, the cumulative blade waste in 2050 is approximately 2.2 million tons. This value represents approximately 1% of remaining landfill capacity by volume, or 0.2% by mass. We also find that the current cost of disposing of blades in large segments or through grinding is relatively low in comparison to the overall life-cycle cost of energy. Based on these findings, landfill space constraints and disposal costs appear unlikely to motivate a change in waste handling strategies under current policy conditions. Instead, more profound shifts in recycling technologies, blade materials, or policy may be needed to move towards a circular economy for wind turbine blades.
Prevalence and Characteristics of Advocacy Curricula in U.S. Medical Schools

PURPOSE: Recent national events, including the COVID-19 pandemic and protests of racial inequities, have drawn attention to the role of physicians in advocating for improvements in the social, economic, and political factors that affect health. Characterizing the current state of advocacy training in U.S. medical schools may help set expectations for physician advocacy and predict future curricular needs. METHOD: Using the members school directory provided by the Association of American Medical Colleges, the authors compiled a list of 154 MD-granting medical schools in the United States in 2019-2020. They used multiple search strategies to identify online course catalogues and advocacy-related curricula using variations of the terms "advocacy," "policy," "equity," and "social determinants of health." They used an iterative process to generate a preliminary coding schema and to code all course descriptions, conducting content analysis to describe the structure of courses and topics covered. RESULTS: Of 134 medical schools with any online course catalogue available, 103 (76.9%) offered at least one advocacy course. Required courses were typically survey courses focused on general content in health policy, population health, or public health/epidemiology, whereas elective courses were more likely to focus specifically on advocacy skills building and to feature field experiences. Of 352 advocacy-specific courses, 93 (26.4%) concentrated on a specific population (e.g., children or persons with low socioeconomic status). Few courses (n = 8) focused on racial/ethnic minorities and racial inequities. CONCLUSIONS: Findings suggest that while most U.S. medical schools offer at least one advocacy course, the majority are elective rather than required, and the structure and content of advocacy-related courses vary substantially. Given the urgency to address social, economic, and political factors affecting health and health equity, this study provides an important and timely overview of the prevalence and content of advocacy curricula at U.S. medical schools.
Silencing Jorge Luis Borges: The Wrongful Suppression of the di Giovanni Translations

Jorge Luis Borges is one of the most important writers in the history of Spanish literature. Borges’s stories, poems, and essays have been translated into English by a handful of translators. However, only Norman Thomas di Giovanni worked side-by-side with Borges for years in Buenos Aires to craft translations Borges personally contributed to and approved. This makes the di Giovanni translations stand out from all others. These translations, which were jointly copyrighted in both men’s names under the Copyright Act of 1909, are considered by many, including Borges himself, to be the author’s truest voice in English. Nevertheless, because Borges split the royalties generated by these translations fifty-fifty with di Giovanni, the financial arrangement drew the ire of Borges’s estate and publisher. After Borges died, his estate and publisher commissioned new translations of all his works, forced the di Giovanni translations out of print, and quashed every effort by di Giovanni to republish or reprint his translations of Borges. Today, the di Giovanni translations are disappearing. Because they are out of print, they have become difficult to find and, in some cases, exorbitantly expensive. This suppression of Borges’s voice in English is offensive from an artistic and ethical standpoint. This article argues it was also illegal. Under the Copyright Act of 1909, this article concludes that the suppression of the di Giovanni translations violated the translator’s rights as a joint author.
A frequency-domain high-speed bus signal integrity compliance model: Design methodology and implementation

This paper investigates channel/link frequency domain compliance in order to predict compatibility with a bus's chip I/O circuitry at its ends. Any channel can be associated with certain frequency domain parameter values which are easily calculated from the channel S-parameter matrix. A set of frequency domain parameters that can sufficiently describe a channel are defined in this paper. Using a genetic algorithm, the frequency domain parameter bounds in a multidimensional space describing PCIe-Gen3 (bus speed = 8 Gb/s) compliant channels are found. Details of the methodology used in order to arrive at the multidimensional frequency domain compliance model, model results and model simulation validation testing are presented.
Horizontal mergers in declining industries: Theory and evidence

Abstract In a declining industry, horizontal merger may allow firms to retire older capacity and to match state-of-the-art capacity. At high levels of market demand, mergers may be privately profitable but socially undesirable and should be prohibited. Here, rationalization of capacity to achieve matching economies is not a sufficient argument to support merger since, at high demand levels, efficiency is gained only at the expense of output suppression. On the other hand, once industry demand has declined to low levels relative to per-firm capacity, privately profitable mergers are socially desirable. Examples of horizontal mergers in declining industries illustrate the general implications of the model.
Prolapse of the vaginal vault: Improved techniques for management of the abdominal approach or vaginal approach

A brief discussion of the history of techniques for the surgical management of prolapse of the vaginal vault is presented. The author's method for the abdominal procedure, sacral colpopexy, is presented together with a summary of twelve patients in whom it was used. The author's modification of the technique of the vaginal operation, "the anterior approach," is presented because it appears to make resection of the enterocele sac and identification of uterosacral ligaments easier and their utilization more effective.
Erythroid bursts produced by friend leukaemia virus in vitro.

WHEN mouse haematopoietic cells are incubated in plasma clot or methyl cellulose cultures in the presence of erythropoietin (EP), at least two kinds of colonies are observed1–4. After 2 days, randomly distributed erythroid colonies (defined as a clone of eight or more benzidine-positive cells) appear1,2, and after 3–8 d of culture with higher concentrations of EP, larger colonies arise in clusters or ‘bursts’3,4. The cells of origin have been termed the colony-forming unit-erythroid (CFU-E)1 and burst-forming unit-erythroid (BFU-E)3,4, respectively. Erythropoiesis in mice is also increased considerably by the Friend virus complex5,6, which has been studied mostly in vivo although there are systems for the study of erythroid transformation in vitro soon after infection7–10. Nooter and Bentvelzen11, using methyl cellulose cultures, showed that mouse marrow cells, previously incubated in vitro with purified Rauscher leukaemia virus, develop more erythroid colonies than untreated control cells. Clarke et al.12, using the plasma clot method, observed erythroid colonies 2 d after incubation of mouse marrow cells with culture fluid from Friend virus infected monolayers of fibroblasts. These colonies were similar to EP-induced 2-d colonies in gross morphology and random distribution throughout the clot. Virus-induced bursts were not present in later stages of culture and erythroid colonies were not induced after incubation of marrow cells with plasma from Friend virus infected mice. We now report that when mouse marrow cells are incubated in vitro with infectious plasma or tissue culture fluids containing the Friend virus complex, a substantial number of erythroid bursts appear 5 d after the initiation of the cultures. The Friend virus complex consists of at least two biologically active viruses—the spleen focus-forming virus (SFFV) which is replication defective and essential for increased erythropoiesis in vivo, and a helper murine leukaemia virus (MuLV-F)13,14.
The challenges with NOTES retroperitoneal access in humans.

Background Animal studies have supported natural orifice transluminal endoscopic surgery (NOTES) retroperitoneal access. NOTES also may offer unique retroperitoneal access in humans.
Abnormal cell calcium concentrations in cultured bone cells obtained from femurs of obese and noninsulin-dependent diabetic rats.

Cytoplasmic free calcium concentration [Ca2+]i was quantified in cultured bone cells with osteoblastic characteristics. The cells were obtained from femurs of obese (fa/fa) Wistar-Kyoto rats, from nonobese, noninsulin-dependent diabetic (NIDD) Sprague Dawley rats, and from their appropriate controls. [Ca2+]i was also determined in bone cells obtained fromin vivo insulin-treated NIDD rats. Obese (Wistar Kyoto) rats had increased body weight (313±13 vs. 249±4 g;P<0.01), decreased femur weights (0.68±0.05 vs. 0.89±0.05 g;P<0.05), similar glucose levels (148±5 vs. 139±3 mg/dl), and higher plasma insulin levels (6.0±0.5 vs. 0.7±0.1 ng/ml;P<0.01) when compared with their nonobese [(fa/+); (+/+)] littermates. Nonobese, NIDD rats, compared with their appropriate controls (nondiabetic Sprague Dawley rats) had higher plasma glucose levels (235±32 vs. 145±3 mg/dl;P<0.01) but their plasma insulins, body weights, and femur weights were similar to controls (0.7±0.1 vs 0.6±0.1 ng/ml; 302±4 vs. 318±14 g; 0.97±0.4 vs. 0.98±0.04 g, respectively). Long-term (4 weeks) daily insulin treatment (2 u/100 g) of the NIDD rats increased their plasma insulin (1.9 ng/ml;P<0.05) and body weight (369±13 g;P<0.05) but did not change their plasma glucose levels (225±5 mg/dl), or femur weights (0.98±0.4 g). [Ca2+]i in bone cells derived from the femurs of obese animals was higher than in cells derived from their nonobese littermates (156±22 vs. 71±13 nM;P<0.01). In bone cells from NIDD rats, [Ca2+]i was lower compared with controls (146±22 vs. 229±19 nM;P<0.001). Insulin treatment of the diabetic animals augmented the decrease in [Ca2+]i in their bone cells (68±11 nM;P<0.005 compared with nontreated rats). These data reveal that [Ca2+]i in cultured bone cells from obese nondiabetic and nonobese NIDD rats differs from that of their controls. Compared with their controls, the changes in [Ca2+]i in bone cells from the NIDD and obese animals were in opposite directions. Whether the underlying mechanisms for the changes in cell [Ca2+]i in nondiabetic obese and nonobese NIDD animals differ, and whether the changes in [Ca2+]i observed in the cultured cells reflect thein vivo condition in bone cells of these animals are questions that await further investigations.
Designing grading policy to motivate student participation in online discussion forum

Online discussion forum has become an important instrument for instructors to create an effective learning environment. However, there lacks the consensus on how to specify grading policies so that students will voluntarily contribute. In this research, we study the effective designs of grading policies and how to appropriately utilise them as incentives to motivate students to participate in online discussion forums. Applying an analytical framework, we model and investigate the performance of different types of grading polices and their effects on student participation in online discussion forums. Our research provides practical guidelines for instructors to offer quality instructions.
The analysis and simulation of an open cycle absorption refrigeration system

Abstract An open cycle absorption refrigeration system is simulated and analyzed. The open cycle differs from the closed cycle in that the open cycle regenerates the weak absorbent solution by evaporating refrigerant to the earth's atmosphere rather than to a condenser. The solar collector used for the open cycle is one in which the weak absorbent solution flows as a fluid film over a flat, open, black surface. The absorbent solution is heated by the black surface and is regenerated by water evaporating to the atmosphere. It was found that the relationship between the collector length and the solution mass flow rate was tied to environmental factors such as wind and humidity when optimizing system performance. The system performance was simulated for five cities using actual weather data. The overall daily cooling COP's (cooling/incident solar) ranged from 0.09 to 0.45 for various conditions.
Functional organization of spectral receptive fields in the primary auditory cortex of the owl monkey.

Recent experiments in the cat have demonstrated that several response parameters, including frequency tuning, intensity tuning, and FM selectivity, are spatially segregated across the isofrequency axis. To investigate whether a similar functional organization exists in the primate, we have studied the spatial distribution of pure-tone receptive field parameters across the primary auditory cortex (AI) in six owl monkeys (Aotus trivirgatus). The distributions of binaural interaction types and onset latency were also examined. Consistent with previous studies, the primary auditory cortex contained a clear cochleotopic organization. We demonstrate here that several other properties of the responses to tonal stimuli also showed nonrandom spatial distributions that were largely independent from each other. In particular, the sharpness of frequency tuning to pure tones, intensity tuning and sensitivity, response latency, and binaural interaction types all showed spatial variations that were independent from the representation of characteristic frequency and from each other. Statistical analysis confirmed that these organizations did not reflect random distributions. The overall organizational pattern of overlaying but independent functional maps that emerged was quite similar to that seen in AI of cats and, in general, appears to reflect a fundamental organization principle of primary sensory cortical fields. J. Comp. Neurol. 415:460–481, 1999. © 1999 Wiley-Liss, Inc.
Density of states in layered superconductor-insulator structures

We study superconductor-insulator layered structures, using a microscopic method based on the Gor'kov equations. We present our results for the single-particle density of states and the order parameter (OP) as a function of the experimental parameters, such as the insulating barrier strength, the coherence length, and the range of transverse momentum of probes. The results provide a very good fit to the tunneling spectra of ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{CaCu}}_{2}$${\mathrm{O}}_{8}$, obtained in a soft-point-contact scanning-tunneling microscopy measurement. The results also indicate that the OP in strongly coupled superconducting regions (such as CuO planes in high-temperature superconductors), may be significantly larger than the energy gap found in experiments. The role of all relevant physical and geometrical parameters is also discussed.
Anti-Ro (SSA) and anti-La (SSB) antibodies in lupus erythematosus and in Sjögren's syndrome.

Lupus erythematosus and Sjogren's syndrome have long been characterized as autoimmune diseases. However, the meaning behind the word autoimmune was and is often vague. Does "autoimmune" in the case of lupus erythematosus and Sjogren's syndrome imply autoantibody-mediated? If so, which autoantibodies are important? At this time, the pathogeneses of lupus erythematosus and Sjogren's syndrome have not been elucidated and it is not possible to answer these questions. Nevertheless, there is, at least in lupus erythematosus, a reasonably large body of experimental evidence supporting the possibility that autoantibody production is the primary abnormality.1In New Zealand black/New Zealand white mice, a strain that spontaneously develops lupus erythematosus with glomerulonephritis, autoantibodies are the first observable abnormality. Detectable levels of antibodies to DNA precede the first signs of renal disease by a few weeks.2Further, in many murine models of lupus erythematosus, the addition of a gene called xid results in
Characterization of atmospheric turbulence using wavefront slope measurements

Turbulence has long been recognized as one of the most significant factors limiting the performance of optical systems operating in the presence of atmosphere. Atmospheric turbulence over vertical paths has been well characterized, both theoretically and experimentally. Much less is known about turbulence over long, horizontal paths. Perturbations of the wavefront phase can be measured using a Hartmann wavefront sensor (H-WFS). These measurements can be used to characterize atmospheric turbulence directly. Theoretical expressions for the slope structure function of the H-WFS measurements are derived and evaluated using numerical quadrature. By concentrating on the slope structure function, we avoid the phase reconstruction step and use the slope measurements in a more direct fashion. The theoretical slope structure function is compared to estimated slope structure functions computed from H-WFS measurements collected in a series of experiments conducted by researchers at the U.S. Air Force's Phillips Laboratory. These experiments involved H-WFS measurements over high altitude (airborne) horizontal paths 20 - 200 km in length.
Mass normalized mode shapes using impact excitation and continuous-scan laser Doppler vibrometry

Conventional scanning laser Doppler vibrometer (LDV) systems cannot be effectively employed with impact excitation because they typically measure a structure's response at only one point at a time. This necessitates exciting the structure at multiple points to create a multi-input-single-output modal test data base, which is not only tedious, but prone to errors due to variations in the impact characteristics from one point to the next. Previous works have demonstrated that an LDV can be used to measure the mode shapes of a structure over a surface by scanning the laser spot continuously as the structure's response decays. The author recently presented a procedure that allows one to post-process continuous-scan LDV (CSLDV) measurements of the free decay of a structure using standard modal parameter identification techniques. Using this approach, one can find the natural frequencies, damping ratios and mode shapes of a structure at hundreds of points simultaneously from a few free responses. The procedure employs a novel resampling approach to transform the continuous-scan measurements into pseudo-frequency response functions, fits a complex mode model, and then accounts for the time delay between samples to obtain the mode shapes. This paper extends the previous work by presenting an algorithm that uses the input force spectrum, measured by an instrumented hammer, to mass normalize the mode shapes obtained using the continuous-scan LDV process. Other issues such as the effect of the scan frequency on the procedure and on speckle noise are also briefly addressed.
The effects of heterogeneity in magma water concentration on the development of flow banding and spherulites in rhyolitic lava

Abstract This study focuses on the origin of flow-banded rhyolites that consist of compositionally similar darker and lighter flow bands of contrasting texture and color. Infrared radiation was used to obtain Fourier transform infrared (FTIR) spectra from which water concentrations were calculated, and to map variations in water concentrations across zones of spherulites and glass from the ~ 23 million year old Sycamore Canyon lava flow of southern Arizona. Lighter-colored, thicker flow bands consist of gray glass, fine-grained quartz, and large (1.0 to 1.5 mm) spherulites. Darker-colored, thinner flow bands consist of orange glass and smaller (0.1 to 0.2 mm) spherulites. The centers of both large and small spherulites are occupied by either (1) a quartz or sanidine crystal, (2) a granophyric intergrowth, or (3) a vesicle. Mapping of water concentration (dominantly OH− in glass and OH− and H2O in sanidine crystals) illustrates fluctuating water availability during quenching of the host melt. Textures of large spherulites in the lighter (gray) bands in some cases indicate complex quenching histories that suggest that local water concentration controlled the generation of glass versus crystals. Small spherulites in darker (orange) bands have only one generation of radiating crystal growth. Both the glass surrounding spherulites, and the crystals in the spherulites contain more water in the gray flow bands than in the orange flow bands. Flow banding in the Sycamore Canyon lava flow may have originated by the stretching of a magma that contained pre-existing zones (vesicles or proto-vesicles) of contrasting water concentration, as the magma flowed in the conduit and on the surface. Variation in the original water concentration in the alternating layers is interpreted to have resulted in differences in undercooling textures in spherulites in the lighter compared to the darker flow bands.
Rates of sensitivity reactions to aspirin: Problems in interpreting the data

This work was done to determine the reasons for variation in the reported rates--ranging from less than 1% to greater than 50%--of sensitivity to aspirin and cross-reactivity to acetaminophen and ibuprofen. In 47 studies that reported rates of sensitivity and in 23 reports that contained series of sensitive patients, we examined the research setting, source of patients, clinical attributes of the study group, admission process, and selection, operational definition, and method of determining sensitivity reactions. In five studies with reasonably well-specified methods, the reported sensitivity rates to aspirin were lowest (0.3% to 0.9%) for patients without allergic tendencies, higher in asthmatics, and highest if patients had nasal polyps or severe atopy. Although not determined in any of these studies, the rate of sensitivity in a general (nonclinical) population would doubtlessly be substantially lower than the rate of three per 1000 reported for nonallergic patients. The admixture of different clinical groups, varying definitions, and ascertainment of a sensitivity reaction seem to be responsible for the variations in the reported rates of sensitivity and cross-reactivity.
Drinking coffee burns hepatic fat by inducing lipophagy coupled with mitochondrial β-oxidation

Coffee is one of the most consumed and popular beverages in the world nowadays. According to the National Coffee Association, more than 60% of American adults drink coffee each day, and an average of 3.1 cups of coffee are consumed by each drinker per day. In spite of its popularity, it has been controversial whether drinking coffee is detrimental or beneficial for human health. While a large body of evidence suggests that drinking coffee may be beneficial for a variety of chronic health conditions including type 2 diabetes, stroke, cancer and all-cause mortality, some other studies suggest that drinking coffee may be a potential hazard for coronary heart disease and may increase mortality in younger drinkers less than 55 years old. 1,2 The reasons for the conflicting results from these large population-based studies could be very complex, but one possibility could be due to the remarkable variety of different types of coffee and the preparation and brewing methods around the world. In contrast to the controversy regarding the health effect of coffee on other organs and tissues, all the experimental and population-based studies support unanimous beneficial effects of drinking coffee on the liver.
Optimized mechanical performance of welded and molded butt joints: Part I: Similarities and differences

Recent developments were oriented on the analysis of the mechanical performance at local (knit lines and welds) and bulk (molded part) areas, with the influence of molding and welding conditions. It has been found that for non-reinforced and reinforced nylon, the mechanical performance in the knit planes and welded areas are approximately equal to the mechanical performance of a base resin (matrix).The observations on similarities and differences in the formation of knit and weld lines are presented in Part I of this paper.
Root-soil contact for the desert succulent Agave deserti in wet and drying soil

SUMMARY To investigate the extent and size of root-soil air gaps that develop during soil drying, resin casts of roots of the desert succulent Agave deserti Engelm. were made in situ for container-grown plants and in the field. Plants that were draughted in containers for 7 and 14 d had 24 and 34% root shrinkage, respectively, leading to root-soil air gaps that would reduce the hydraulic conductivity at the root-soil interface by a factor of about 5. When containers were vibrated during drought, root-soil air gaps were greatly diminished, and the predicted conductivity at the interface was similar to that of the control (moist soil). For plants in the field (4 and 6 wk after the last rainfall), root shrinkage was greater than for container-grown plants, but root-soil contact on the root periphery was greater, which led to a higher predicted hydraulic conductivity at the root-soil interface. To test the hypothesis that root-soil air gaps would help to limit water efflux from roots in drying soil, the water potentials of the soil, root, and shoot of plants from vibrated containers (with gaps eliminated or reduced) and non-vibrated containers were compared. The soil water potential was lower for vibrated containers after 14 d of drought, suggesting more rapid depletion of soil water due to better root-soil contact, and the root water potential was lower as well, suggesting greater water loss by roots in the absence of root-soil air gaps. Thus, air gaps could benefit A. deserti by helping to maintain a higher root water potential in the early stages of drought and later by limiting root water loss at the root-soil interface when the water potential exceeds that of the soil.
The political economy of unfunded public pension liabilities

This paper applies a public choice approach to the problem of unfunded pension liabilities and adopts the methodology of Congleton and Shughart (1990) to model underfunding of state-level public pension plans using the median voter theorem, along with the theory of “capture” by special interest groups, and a combined model of the two. With panel data from 2001 to 2009, the paper finds that the combined model provides the strongest explanation for the current levels of unfunded liabilities; hence, both median voter preferences and special interest group influence are affecting political outcomes. The special interest group model slightly outperforms the median voter model in direct comparisons.
Electronic structure and properties of d- and f-shell-metal compounds

Bonding in rock-salt--structure compounds is described. For NaCl, the bonding is in terms of electrons occupying chlorine p bands, lowered in energy by interaction with the sodium s states, and an overlap repulsion arises from nonorthogonality of states on neighboring ions. For transition-metal compounds d-like states are added, with their coupling with the nonmetallic p states. This coupling is taken to be of the form ${\ensuremath{\eta}}_{\mathrm{pdm}}$${\ensuremath{\Elzxh}}^{2}$(${r}_{p}$${r}_{d}^{3}$${)}^{1/2}$/(${\mathrm{md}}^{4}$), with ${r}_{p}$ and ${r}_{d}$ tabulated for each element. An additional overlap repulsion, proportional to ${\ensuremath{\Elzxh}}^{2}$${r}_{p}$${r}_{d}^{3}$/(${\mathrm{md}}^{6}$) and to the number of electrons occupying the corresponding bands, also arises from this interaction. The simplest systems, such as KF, CaO, ScN, and TiC, contain eight valence electrons per atom pair and all but TiC are insulating. The extra energy from the covalent pd coupling is calculated; it decreases the lattice distance and increases the cohesion and bulk modulus. With a total valence of 9--12, the excess electrons occupy nonbonding bands making the compound metallic, but not significantly modifying the bonding properties.A total valence of 13--18 would require electrons in antibonding bands and such compounds appear not to occur in the rock-salt structure unless intra-atomic Coulomb interactions are strong enough (as in the heavy-3d-metal compounds) to produce a correlated state, insulating, magnetic, and with suppressed covalent interactions. The form of the condition for the formation of a correlated state is written. This same general theory is applied also to f-shell compounds, those of the rare earths and actinides, with pf coupling proportional to ${\ensuremath{\Elzxh}}^{2}$(${r}_{p}$${r}_{f}^{5}$${)}^{1/2}$/(${\mathrm{md}}^{5}$) replacing the pd coupling of the transition-metal compounds. The theory suggests that a correlated state of the f electrons may be expected except for cerium compounds and compounds of the light actinides. The phosphides of the actinides are predicted to, and found to, have minimum spacing at the uranium phosphide which occurs as the metal f level drops below the nonmetal p level; the effect is less pronounced experimentally in the nitrides, arsenides, and sulphides. The contribution of the pf bonding to the cohesion increases through the series as long as the f levels do not form correlated states.
Focal nodular hyperplasia in pediatric allogeneic hematopoietic cell transplant: case series.

Focal nodular hyperplasia in pediatric allogeneic hematopoietic cell transplant: case series
Examining neurocognitive correlates of risky driving behavior in young adults using a simulated driving environment

Young adults aged 18-24 account for a disproportionate number of motor vehicle accidents, yet the neurocognitive factors that contribute to increased crash risk are not often studied in this age group. The present study examined the contributions of risk taking propensity, executive functioning, and attention to performance on a virtual reality driving task. Participants completed a driving task, as well as a battery of neurocognitive tests. Results showed that greater risk taking propensity and better performance on a measure of attention and processing speed predicted higher speeds. Implications for assessment and rehabilitation in young adult populations are discussed.
The Effects of Emotional Arousal and Increased Speaking Rate on Children's Newly Learned /r/ Productions.

Abstract Generalization of newly learned phones into spontaneous speech remains a serious problem for many children with articulation disorders. It has been suggested that generalization may be governed, at least in part, by the stability of the new phone. Various clinicians have argued that response stability, in turn, may be affected by emotion and speaking rate. The present study was designed to determine whether children's newly learned /r/ phones would be adversely affected by unpleasant emotions and/or faster than normal speaking rates. Sixteen misarticulating children retold a story after frustration and no frustration procedures, in combination with slow and fast slide presentations. In contrast to previous clinical assumptions, no significant differences in subjects' /r/ productions were found among the conditions. The research implications and limitations, and suggestions for future research, are discussed.
Stability of the Le Fort I maxillary osteotomy after rigid internal fixation.

Abstract Purpose: The purpose of this study was to evaluate the postsurgical stability of the Le Fort I osteotomy with impaction in which rigid internal fixation was used for stabilization. Materials and Methods: Lateral cephalograms of 19 patients were evaluated. Descriptive statistics were compiled that included absolute linear and angular measurements as well as absolute changes in measurements for successive cephalometric radiographs. Comparisons were made from 1) presurgery to immediate postsurgery, 2) immediate postsurgery to splint removal, 3) splint removal to longest follow-up, and 4) immediate postsurgery to longest follow-up. Repeated measures analysis of variance were used to describe significant differences for absolute changes in measurements. Results: All surgical movements were significant except for horizontal position of dental structures, horizontal position of the posterior mandible, and posterior vertical facial height. All significant movement from immediate postsurgery to splint removal was secondary to removal of the occlusal splint. Changes were minimal from splint removal to longest follow-up, with only 3 of 24 measurements showing statistically significant differences. These measurements related to tooth position and were affected by postsurgical orthodontics. The data derived from this study were also compared with those found in similar studies in which fixation was by wire osteosynthesis. Conclusions: The magnitude of postoperative movement was considerably less with rigid internal fixation than that reported with the use of wire fixation. This is attributed to the increased stabilizing effect of rigid internal fixation.
Nine centuries of microparticle deposition at the South Pole

The analysis of microparticles in a 101-m core from Amundsen-Scott South Pole Station, Antarctica has revealed a substantial increase in total particle concentration between approximately 1450 and 1850 A.D., a period encompassing the latest neoglacial interval or Little Ice Age. It is likely that this reflects a simultaneous increase in the concentration of particulate material in the Antarctic atmosphere. This is important climatologically, for the Antarctic atmosphere may represent the closest approximation to the natural background aerosol. Thus cores from East Antarctica may contain long and detailed records of the natural global background aerosol. Such records are unavailable from any other medium. Additionally, a cyclical variation which appears to be annual has been detected in the South Pole particle record. These features allow construction of a relative time scale for ice cores older than 100 yr from regions of low accumulation (<10 g a−1) where many traditional techniques are not applicable. This is especially significant, as the comparison of climatic data extracted from ice cores with other records of proxy data depends upon the ability to assign an accurate time scale to the ice core. An estimated nine-century record of net annual accumulation at the South Pole has been compiled and the calculated error in the time scale is ±90 yr.
Kinetics and Structural Characterization of Calcium-Based Sorbents Calcined under Subatmospheric Conditions for the High-Temperature CO2 Capture Process

The influence of several process parameters on the calcination of a naturally occurring limestone and a precipitated mesoporous calcium carbonate (CaCO3) sorbent structure to calcium oxide (CaO) is detailed in this study. CaCO3 calcination is an integral part of a multicyclic carbonation−calcination reaction (CCR) process that separates carbon dioxide (CO2) from high-temperature gas mixtures into a pure CO2 stream. Maintenance of high sorbent reactivity over repeated CCR cycles reduces the capital and operating cost of the CCR process. A lower calcination temperature, required to maintain high sorbent reactivity, reduces the calcination rate of CaCO3. This study investigates various process conditions such as subatmospheric calcination, sorbent dispersion in a rotary calciner, use of a high thermal conductivity sweep gas, etc. in enhancing the calcination rate at lower calcination temperatures. The high-temperature gas−solid carbonation studies of the resulting CaO sorbent prove the necessity to maintain ...
Chloroplast DNA from tobacco leaves.

DNA from tobacco leaf chloroplasts was isolated as a single component with a buoyant density in CsCl of 1.702 compared to 1.697 for nuclear DNA. 5-Methylcytosine is present in nuclear DNA but absent in chloroplast DNA. Chloroplast DNA, with a guanine-cytosine content of 43 percent, has a melting temperature of 86°C and renatures completely on slow cooling, whereas nuclear DNA ( melting temperature, 84°C; guanine-cytosine content, 40 percent) does not renature. About 9 percent of the total DNA in tobacco leaves is chloroplast DNA representing about 4.7 xX 10-15 gram of DNA per chloroplast with a molecular weight of approximately 4 xX 107.