cssi/SciSciGPT-SciSciNet huggingface dataset:
Human spaceflight and space adaptations: Computational simulation of gravitational unloading on the spine

Abstract Living in reduced gravitational environments for a prolonged duration such, as a fly by mission to Mars or an extended stay at the international space station, affects the human body - in particular, the spine. As the spine adapts to spaceflight, morphological and physiological changes cause the mechanical integrity of the spinal column to be compromised, potentially endangering internal organs, nervous health, and human body mechanical function. Therefore, a high fidelity computational model and simulation of the whole human spine was created and validated for the purpose of investigating the mechanical integrity of the spine in crew members during exploratory space missions. A spaceflight exposed spine has been developed through the adaptation of a three-dimensional nonlinear finite element model with the updated Lagrangian formulation of a healthy ground-based human spine in vivo. Simulation of the porohyperelastic response of the intervertebral disc to mechanical unloading resulted in a model capable of accurately predicting spinal swelling/lengthening, spinal motion, and internal stress distribution. The curvature of this space adaptation exposed spine model was compared to a control terrestrial-based finite element model, indicating how the shape changed. Finally, the potential of injury sites to crew members are predicted for a typical 9 day mission.
Cardiac Implantable Electronic Devices in Patients With Left Ventricular Assist Systems.

Recent progress and evolution in device engineering, surgical implantation practices, and periprocedural management have advanced the promise of durable support with left ventricular assist systems (LVAS) in patients with stage D heart failure. With greater uptake of LVAS globally, a growing population of LVAS recipients have pre-existing cardiac implantable electronic devices (CIEDs). Strategies for optimal clinical management of CIEDs in patients with durable LVAS are evolving, and clinicians will increasingly face complex decisions regarding implantation, programming, deactivation, and removal of CIEDs. Traditional decision-making pathways for CIEDs may not apply to LVAS-supported patients, as few patients die of arrhythmic causes and many arrhythmias may be well tolerated. Given limited data, treatment decisions must be individualized and made collaboratively among electrophysiologists, advanced heart failure specialists, and patients and their caregivers. Large, prospective, well-conducted studies are needed to better understand the contemporary utility of CIEDs in patients with newer-generation LVAS.
Biogenetic pathways and targeting signals in polarized epithelia

Polarization of proteins and lipids into opposite surface domains of epithelial cells is essential for their specialized vectorial functions in transport and secretion. Recent work indicates that this polarity results from selective delivery to and retention at the appropriate domain (Rodriguez-Boulan and Nelson, 1989). Selective enrichment of glyco-lipids in the apical surface may protect the epithelial cell from the external environment (Simons and van Meer, 1988). Tight junctions confer selective paracellular permeability restrictions to ions and macromolecules and prevent diffusion of proteins and lipids in the extracellular leaflet from one domain to the other (van Meer, 1989). Lateral junctional complexes mediate adhesion between cells and help maintain the integrity of the epithelial sheet. The apical membrane is the ‘private’ domain of epithelial cells, with many epithelial-specific molecules, whereas the basolateral surface is the ‘public’ domain, sharing many components with non-polarized cells (Simons and Wandinger-Ness, 1990).
Electron Transport Across Cu/Ta(O)/Ru(O)/Cu Interfaces in Advanced Vertical Interconnects

Abstract The vertical resistance of Cu/Ta/Ru/Cu stacks is calculated using a combination of first-principles density functional theory (DFT) and a Non-Equilibrium Green’s Function (NEGF) formalism. The effects of oxidizing either one or both of the Ta and Ru layers are analyzed. These oxides can be either metallic (TaO and RuO2) or insulating (Ta2O5) in nature. Simulations indicate that for the metallic oxides, the presence of RuO2 results in more electron scattering than TaO. Complete oxidation of both Ta/Ru layers results in a ≈ 3 × increase in resistance for Cu/TaO/RuO2/Cu relative to the un-oxidized structure, and a ≈ 8 x increase in resistance for Cu/Ta2O5/RuO2/Cu relative to the un-oxidized structure. Electron transmission/reflection coefficients as well as values of total resistance are reported for each interface structure. These results highlight the importance of identifying and controlling oxygen contamination in high-volume manufacturing in order to obtain low resistance vertical interconnects and favorable device performance.
Ten Thousand Consecutive Gastrectomies for Gastric Cancer: Perspectives of a Master Surgeon

As radical gastrectomy with lymph node dissection is currently the best strategy to cure gastric cancer, the role of the surgeon remains quite important in conquering it. Dr. Sung Hoon Noh, a surgeon and surgical oncologist specializing in gastric cancer, has treated gastric cancer for 30 years and has conducted over 10000 cases of gastrectomy for gastric cancer. He first adapted an electrocautery device into gastric cancer surgery and has led standardization of surgical procedures, including spleen preserving gastrectomy. His procedures based on patient-oriented insights have become the basis of the concept of enhanced recovery after surgery. He has also contributed to improving patient's survival through adoption of a multidisciplinary approach: he proved the benefit of adjuvant chemotherapy after radical D2 gastrectomy for stage II/III gastric cancer in clinical trials, updating treatment guidelines throughout the world. Dr. Noh also opened the era of precision medicine for treating gastric cancer, as he developed and validated a mRNA expression based algorithm to predict prognosis and response to chemotherapy. This article reviews his contribution and long history of service in the field of gastric cancer. The perspectives of this master surgeon, based on his profound experience and insights, will outline directions for integrative multidisciplinary health care and how can surgeons prepare for the future.
An implanted pH sensor read using radiography

A biomedical sensor was developed to measure local pH near orthopedic implants to detect and study implant-associated infection. The sensor is read using plain radiography, a technique which is noninvasive, inexpensive, ubiquitously available in medical facilities, and routinely used in diagnosis and follow-up. The sensor comprises a radiopaque tungsten indicator pin embedded within a chemically responsive hydrogel that exhibits a pH-dependent swelling. A stainless steel well holds this hydrogel and attaches to an orthopedic plate. The local pH may be determined from the extent of hydrogel swelling by radiographically measuring the indicator position relative to the well. We calibrated the sensor in a series of standard pH buffers and tested it during bacterial growth in culture. The sensor was robust: its response was negligibly affected by changes in temperature, ionic strength within the normal physiological range, or long-term incubation with reactive oxygen species generated from hydrogen peroxide and copper. Pooled data from several sensors fabricated at different times and tested in different conditions had a root-mean-square deviation from a pH electrode reading of 0.24 pH units. Radiographic measurements were also performed in cadaveric tissue with the sensor attached to an orthopedic plate fixed to a tibia. Pin position readings varied by 100 μm between observers surveying the same radiographs, corresponding to 0.065 pH units precision in the range pH 4-8. The sensor was designed to augment standard radiographs of tissue, bony anatomy, and hardware by also indicating local chemical concentrations.
Exploring the public’s knowledge about kinship care: a cross-sectional study

Public knowledge can be integral to building broad-based support for programs and policies related to kinship care. Despite this importance, few, if any, studies have examined this topic. This expl...
Planning at decision time and in the background during spatial navigation

Planning is the model-based approach to solving control problems. The hallmark of planning is the endogenous generation of dynamical representations of future states, like goal locations, or state sequences, like trajectories to the goal location, using an internal model of the task. We review recent evidence of model-based planning processes and the representation of future goal states in the brain of rodents and humans engaged in spatial navigation tasks. We highlight two distinct but complementary usages of planning as identified in artificial intelligence: ‘at decision time’, to support goal-directed choices and sequential memory encoding, and ‘in the background’, to learn behavioral policies and to optimize internal models. We discuss how two kinds of internally generated sequences in the hippocampus – theta and SWR sequences – might participate in the neuronal implementation of these two planning modes, thus supporting a flexible model-based system for adaptive cognition and action.
THE IMPACTS OF NIGERIAN HOME MOVIES ON THE BEHAVIORAL PATTERN OF NIGERIAN YOUTH

Movies have both positive and negative impacts on the youth, especially students. The need to bring about sanity in the industry can therefore not be over emphasized, with a view to salvaging the cultural values and morals of the people, while also attending to the other communication needs of the society. This is realizable through decent information dissemination, education, mobilization and entertainment of the citizenry, with special focus on the youth. A lot of the youths demonstrate negative attitude as a result of their exposure to violent films. The proliferation of local films appears to be adding to the problems of our society; hence, the need to ensure thorough scrutiny before production and marketing of home movies in order to achieve positive impacts on the generality of Nigerian society. The study has a sample size of 200. Respondents were drawn from Amuwo-Odofin Local Government Area of Lagos State. The survey research method was used to generate information on the impacts of Nigerian home movies on the youths. Three research hypotheses were developed and when tested, two of the hypotheses tested positive, while one failed because of the violence associated with some home movies. The analysis is presented using tables and simple percentages. Findings indicate that Nigerian home movies exert positive and negative influence on the behavioural patterns of the students in the secondary and tertiary institutions studied in Amumo Odofin and Lagos State at large. The paper therefore recommends that Nigerian home movies become sensitive to our cultural values, morals and languages to achieve the desired goals and for national development.
Goal-directed fluid therapy in autologous breast reconstruction results in less fluid and more vasopressor administration without outcome compromise.

Summary Objective Aggressive or restricted perioperative fluid management has been shown to increase complications in patients undergoing microsurgery. Goal-directed fluid therapy (GDFT) aims to administer fluid, vasoactive agents, and inotropes according to each patient's hemodynamic indices. This study assesses GDFT impact on perioperative outcomes of autologous breast reconstruction (ABR) patients, as there remains a gap in management understanding. We hypothesize that GDFT will have lower fluid administration and equivocal outcomes compared to patients not on GDFT. Methods A single-center retrospective review was conducted on ABR patients from January 2010-April 2017. An enhanced recovery after surgery (ERAS) using GDFT was implemented in April 2015. With GDFT, patients were administered intraoperative fluids and vasoactive agents according to hemodynamic indices. Patients prior to April 2015 were included in the pre-ERAS cohort. Primary outcomes included the amount and rate of fluid delivery, urine output (UOP), vasopressor administration, major (i.e., flap failure) and minor (i.e., seroma) complications, and length of stay (LOS). Results Overall, 777 patients underwent ABR (ERAS: 312 and pre-ERAS: 465). ERAS patients received significantly less total fluid volume (ERAS median: 3750 mL [IQR: 3000–4500 mL]; pre-ERAS median: 5000 mL [IQR 4000–6400 mL]; and p Conclusions GDFT, as part of ERAS, and the prudent use of vasopressors were found to be safe and did not increase morbidity in ABR patients. GDFT provides individualized perioperative care to the ABR patient.
The Political Economy of the European Union : An Exploration of EU Institutions and Governance from the Perspective of Polycentrism

The analytical framework of polycentrism—extensively developed by Elinor and Vincent Ostrom—is one of the most prominent theoretical approaches in political economy. According to this theory, social systems with multiple layers of decision-making and a mix of shared and individual responsibilities among subunits often have advantages in the provision of public goods and other aspects of governance. This chapter explores the extent to which the European Union (EU) can be described, categorized, and analyzed as a polycentric governance system. The EU consists of a large number of individual states that retain a certain degree of autonomy, yet operate under an overarching institutional superstructure with a common set of rules. The superstructure itself is characterized by a high degree of decentralization in decision-making authority. Furthermore, many responsibilities for the provision of public goods and services remain in the hands of regional and local governments. Therefore, the division of power within the EU largely mirrors the ideals of polycentricity. In addition to an analysis of the EU’s institutional framework, I investigate polycentric governance “in action” by analyzing (1) the sovereign debt crisis and (2) the international refugee crisis. When facing these major political-economic challenges, the EU’s response consisted of a mix of centralized and decentralized initiatives. As we would expect from a polycentric system of governance, only the combination of policies initiated at both levels successfully addressed the consequences of the crises. Finally, I consider theoretical and practical aspects of “leaving a polycentric system,” with a focus on Brexit.
Characterizations of Resonant Converters Based DC Transformers for Microgrid Application

Conventional line frequency transformers have the disadvantages of large volume and low efficiency. The medium or high frequency transformers based on power converters can achieve high power conversion with small footprint have drawn popularity in numerous industrial applications. Unregulated resonant converters, LLC and CLLC resonant converters, with fixed voltage conversion ratio operating at resonant frequency, which are also known as DC transformers (DCTs), are attractive owning to their high efficiency characteristic. Nevertheless, there are issues associated with DCTs in real applications. Regulation capability and automatic resonant frequency tracking capability are the two most important issues for DCTs. The main work of this paper is to characterize the resonant converters based DCTs, and overview the issues and solutions associated with DCTs. Guidelines can be provided for researchers and engineers when designing the resonant converters based DCTs.
Broadband Terahertz Time-Domain Imaging Using a Terahertz Focal-Plane Array

We present a terahertz time-domain imaging modality based on a terahertz focal-plane array. The imaging system has more than a 60-dB signal-to-noise ratio and can resolve terahertz images up to 2.5 THz.
Interfield Connections and Psychology

Woodward and Devonis propose a program for analyzing the history of psychology based on the notion of interfield theory. Both of us have long been interested in relations between fields or disciplines of science, and one of us (WB) has analyzed a number of examples of interfield theories. The notion of an interfield theory was developed for quite specific purposes, however, and it is not clear that it can bear the load Woodward and Devonis seek to place upon it. We will first indicate some of the challenges that will confront any attempt to apply the notion of interfield theory to analyzing the development of psychology as a discipline and then offer an alternative perspective on psychology as a discipline, from which we might then apply the notion of interfield theory fruitfully in a more restricted way. In addition to advancing a framework for analyzing the development of psychology, Woodward and Devonis also advance interpretations of specific aspects of psychology’s history. Some of these interpretations are open to challenge or alternative formulations; however, we have chosen to restrict our focus to questions raised by their application of interfield theory.
Evaluation of the rate-determining steps and the relative magnitude of the individual rate constants for the hydrolytic and synthetic activities of the catalytic component of liver microsomal glucose 6-phosphatase.

Abstract 1. Steady state kinetic constants were determined at pH 6 for various phosphohydrolase and phosphotransferase activities catalyzed by glucose 6-phosphatase of liver microsomes that were supplemented with 0.4% sodium taurocholate and assayed in the presence of albumin. Km and Vmax values were evaluated for reactions with glucose 6-phosphate, carbamyl phosphate, inorganic pyrophosphate, mannose 6-phosphate, ATP, and phosphoenolpyruvate as phosphoryl donor compounds and d-glucose and d-mannose as phosphoryl acceptor compounds. 2. The order of decreasing reactivity of these substrates was carbamyl phosphate g inorganic pyrophosphate g mannose 6-phosphate = glucose 6-phosphate >> ATP g phosphoenolpyruvate. Phosphotransferase activities with d-mannose were significantly faster than the corresponding glucose phosphotransferase activities. With the exception of phosphoenolpyruvate, values for Vmax and Km for a given phosphate substrate were greater in the phosphotransferase reactions. The Km for a given substrate in the phosphotransferase reaction varied with the specific nature and concentration of the second substrate. Values of Km for the phosphoryl donor substrates were greatest with mannose as the acceptor, while Km values for the phosphoryl acceptor varied directly with the reactivity of the phosphoryl donor compound. 3. These observations were shown to be incompatible with the conclusion from an earlier study that the rate-limiting step in the mechanism was the formation of the phosphoryl enzyme from the binary complex of enzyme and phosphoryl donor compound. Rather, it is concluded that the hydrolysis of phosphoryl enzyme is the slowest step in the hydrolysis of all substrates that possess reactivity equal to or greater than glucose 6-phosphate. Moreover, no individual rate constant could be considered as the "rate-limiting factor" in these reactions. The earlier conclusions appear to be valid at pH 6 in the cases of phosphoenolpyruvate, ATP, or other nucleotides where additional steric or electrostatic factors restrict the rate of formation of phosphoryl enzyme. 4. An analysis of the data for all activities permitted the assignment of upper and lower limits on the relative magnitude of the individual rate constants for the glucose 6-phosphate phosphohydrolase activity and means by which these limits may be refined are discussed.
Approximate inference in graphical models using lp relaxations

Graphical models such as Markov random fields have been successfully applied to a wide variety of fields, from computer vision and natural language processing, to computational biology. Exact probabilistic inference is generally intractable in complex models having many dependencies between the variables. We present new approaches to approximate inference based on linear programming (LP) relaxations. Our algorithms optimize over the cycle relaxation of the marginal polytope, which we show to be closely related to the first lifting of the Sherali-Adams hierarchy, and is significantly tighter than the pairwise LP relaxation. We show how to efficiently optimize over the cycle relaxation using a cutting-plane algorithm that iteratively introduces constraints into the relaxation. We provide a criterion to determine which constraints would be most helpful in tightening the relaxation, and give efficient algorithms for solving the search problem of finding the best cycle constraint to add according to this criterion. By solving the LP relaxations in the dual, we obtain efficient message-passing algorithms that, when the relaxations are tight, can provably find the most likely (MAP) configuration. Our algorithms succeed at finding the MAP configuration in protein side-chain placement, protein design, and stereo vision problems. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
U.S. Federal Government attempts to promote primary care training.

Abstract The federal government of the United States is concerned that only 30‐33% of physicians are in primary care practice and not more than approximately 15‐20% of recent medical graduates choose primary care. Moreover, the distribution of interns and residents in primary care in recent years is 40% and after “branching” it is realistically only 25%. The federal government's goal through legislative intervention is to increase the pool of U.S. medical graduates to enter primary care from the current level to at least 50% by the turn of the century. To attain this goal, the government is depending on health care reform legislation and making changes in federal legislation that reimburses graduate medical education through direct and indirect Medicare payments. The federal government hopes to produce incentives to increase the pool of primary care physicians and to place disincentives on sub‐specialty training by altering direct and indirect Medicare payments in favor of primary care training programs; ...
A longitudinal examination of the transition into senior high school for adolescents from urban, low-income status, and predominantly minority backgrounds.

The current 6-year study investigates the impact of the elementary (K–8)-to-high school (9–12) transition on the school completion outcomes of 107 adolescents from urban, minority, low-income status backgrounds. Descriptive findings provide a longitudinal profile of students' enrollment status throughout high school. Students who had graduated or were Active in the school system at the end of the study evidenced more marked change in perceptions of social support following the transition to the ninth grade compared to Inactive students, dropouts, who evidenced little change. With respect to academic performance, while both groups evidenced declines following the transition and failed to recover sustained losses, Inactive students declined more sharply in grades and attendance. Findings are discussed in terms of the mixed support for the transitional life events perspective. In addition, study limitations and directions for future research are discussed, including variables that should be considered in research with the targeted group.
An AC Magnetohydrodynamic Microfluidic Switch

A microfluidic switch has been demonstrated using an AC Magnetohydrodynamic (MHD) pumping mechanism in which the Lorentz force is used to pump an electrolytic solution. By integrating two AC MHD pumps into different arms of a Y-shaped fluidic circuit, flow can be switched between the two arms. This type of switch can be used to produce complex fluidic routing, which may have multiple applications in µ.TAS.
Aluminum Monolithic Alloy and Multi‐Alloy Cast Using Planar Solidification Approach

Direct-Chill (DC) casting of aluminum ingots and billets for the subsequent manufacture of wrought product forms has been the established industry standard practice for the past 80 years. The through-thickness characteristics of aluminum products are well understood and are affected by the phenomena of macrosegregation which occurs during casting. In the present work, two new classes of alloy ingot were cast using a novel planar solidification approach. One class is a monolithic alloy ingot with a highly uniform composition through the thickness. The other class is multi-alloy ingot with engineered compositional gradients through the thickness. The chemical and microstructural characteristics of these cast materials are discussed and compared to conventional DC ingot.
Sample Rate Effects on Disturbance Rejection for Digital Control Systems

Sample rate effects on disturbance rejection are discussed through design examples of a double integrator plant and mass-spring-mass systems. Disturbance rejection is one of the key factors that influences the sample rate selection. The discrete nature of digital control systems contributes to performance degradation compared to continuous controllers. The results show that a sample rate has a significant effect on the performance of a discrete controller's disturbance rejection. Based on the representative examples analyzed, the performance of systems, where the process disturbance is dominant, approaches the performance of a continuous controller to within 10% when using a sample rate of 40 or more times the closed-loop bandwidth, provided that there are no significant dynamics faster than the bandwidth. If a 50% degradation of the discrete system performance is acceptable, this can usually be achieved with a sample rate which is 8 times the closed-loop bandwidth. However, for the class of systems where the controller adds a significant amount of damping to a lightly damped mode which is faster than the bandwidth, the open-loop frequency of that mode has a large impact on the sample rate selection. Such a lightly damped mode causes sensitive sample rates near integer fractions of twice the mode frequency, where the performance degrades significantly. For this class of systems, it may be necessary to increase the sample rate over that suggested above in order to maintain acceptable performance.
N\'eel and Valence-Bond Crystal phases of the Two-Dimensional Heisenberg Model on the Checkerboard Lattice

I use an improved version of the two-step density matrix renormalization group method to study ground-state properties of the 2D Heisenberg model on the checkerboard lattice. In this version the Hamiltonian is projected on a tensor product of two-leg ladders instead of chains. This allows investigations of 2D isotropic models. I show that this method can describe both the magnetically disordered and ordered phases. The ground-state phases of the checkerboard model as $J_2$ increases are: (i) N\'eel with $Q=(\pi,\pi)$, (ii) a valence bond crystal (VBC) of plaquettes, (iii) N\'eel with $Q=(\pi/2,\pi)$, and (iv) a VBC of crossed dimers. In agreement with previous results, I find that at the isotropic point $J_2=J_1$, the ground state is made of weakly interacting plaquettes with a large gap $\Delta \approx 0.67 J_1$ to triplet excitations.
Perspectives of Hospital‐Based Nurses on Breastfeeding Initiation Best Practices

ABSTRACT Objective To assess the variation in breastfeeding knowledge and practices of registered nurses in hospital women and family‐care units and the informal and formal hospital policies related to the initiation and support of breastfeeding. Design This qualitative study employed a focus group approach to solicit perceptions of hospital‐based nurses regarding breastfeeding best practices. Setting Eight state hospitals stratified by socioeconomic status (SES) and size served as settings to recruit participants for this study. Participants Forty female registered nurses from labor and delivery ( n =9), postpartum ( n= 13), labor and delivery/recovery/postpartum care (LDRP) ( n= 12) and neonatal intensive care unit (NICU) ( n= 6) constituted eight focus groups. Results The majority of nurses reported being knowledgeable of evidence‐based best practices related to breastfeeding initiation. However, in non‐Baby Friendly/Baby Friendly Intent (non‐BF/BFI) settings, nurses' knowledge often was not in accordance with current best practices in breastfeeding initiation, and reported hospital policies were not based upon evidence‐based practices. Barriers to best practices in breastfeeding initiation included hospital lactation policies (formal and informal), nurses' limited education in breastfeeding initiation best practices, high rates of surgical delivery, and lack of continuity of care with the transition of responsibility from one nurse to another from labor and delivery to transition care to postpartum care. Conclusions A significant disparity between nurses' intention to support breastfeeding and their knowledge suggests a need for education based on the World Health Organization Baby Friendly standards for nurses at non‐BF/BFI hospitals. A significant barrier to supporting breastfeeding is lack of hospital policy and inappropriate or outdated policy.
Dairy and weight loss hypothesis

In their recent assessment of clinical trials evaluating the hypothesis that dairy foods favorably impact weight management, Lanou and Barnard1 have overlooked several key facts. First, the dairy and weight management hypothesis does not predict an effect of dairy on body weight loss in the absence of energy restriction. Instead, it predicts an augmentation of weight and fat loss during well-controlled energy restriction and a redistribution of energy resulting in a loss of body fat with no change in body weight in the absence of energy restriction (see recent review2). Consequently, the hypothesis predicts little or no effect of either calcium or dairy on body weight in the reviewed studies that did not include an energy-restriction component. When viewed in that context, the results of the Women's Health Initiative demonstrating that calcium significantly attenuated the risk of moderate (>3 kg) postmenopausal weight gain in a randomized, double-blind, placebo-controlled trial of 36,282 subjects3 lend substantial support for the hypothesis and should not be dismissed as merely “showing a small reduction in the rate of weight gain”.1 Most of the remaining studies that failed to find an effect were designed to assess skeletal rather than energy metabolism or adiposity endpoints and, …
Aerodynamics. Flight of the robofly.

Qualitative studies of airflow over insect wings have long been possible, thanks to the use of smoke trails. With a new robotic fly, flow and force can be analysed quantitatively, so theories of insect flight can be tested.
Sickle Cell Trait as a Risk Factor for Secondary Hemorrhage in Children With Traumatic Hyphema

Purpose To determine risk factors for secondary hemorrhage and poor visual outcome in children with traumatic hyphemas. Methods We reviewed 99 eyes of 97 children younger than 18 years who had been hospitalized for hyphema within 48 hours of blunt eye trauma. Inpatient records were examined for race, age, sickle cell trait status, size of hyphema and intraocular pressure at admission, secondary hemorrhage (rebleed of hyphema), and medications while hospitalized. Fifty-five eyes of 53 children had at least 1 month of follow-up or attained best-corrected visual acuity of 20/50 or better at their last outpatient visit. Results Among 99 eyes of 97 children with traumatic hyphema, secondary hemorrhage occurred in nine eyes (9%). Among 72 eyes of 70 African-American children, secondary hemorrhage occurred in nine eyes (14%), whereas in 27 eyes of 27 white children, there were no secondary hemorrhages. However, when the 14 eyes of 13 sickle cell trait-positive children were excluded from the African-American group, the 57 eyes of sickle cell trait-negative African-American and white children did not have any secondary hemorrhages. The sickle cell trait-positive group had secondary hemorrhages in nine of 14 eyes (64%), significantly ( P Conclusion Sickle cell trait is a significant risk factor for secondary hemorrhage, increased intraocular pressure, and permanent visual impairment in children who have traumatic hyphemas following blunt trauma.
Evaluation of 5,000 endodontic treatments: Incidence of the opened tooth

Five thousand endodontic cases treated by three endodontists were reviewed to determine the frequency of the need to leave teeth opened for drainage. The subsequent treatment of these teeth is described. Of the 5,000 cases reviewed, 518 were left open at some point during treatment. Two hundred and eighty-one cases (54.2 percent) remained closed after the first closure. Four hundred and twenty-six (82.2 percent) of the cases opened were eventually completed without surgical intervention. The need to prescribe antibiotics and perform a trephination is also stated.
Detection of pathogenic Leptospira spp. through TaqMan polymerase chain reaction targeting the LipL32 gene

Rapid diagnosis of leptospirosis, through culture and/or serology, can be difficult without proper expertise and is often delayed because of the length of time required to obtain results. In this study, we developed a real-time polymerase chain reaction (PCR) assay using a TaqMan probe targeting lipL32, which is present only in pathogenic Leptospira spp. Using Leptospira interrogans serovar Icterohaemorrhagiae DNA, the lower limit of detection was found to be 20 genomic equivalents/reaction with a 95% cutoff value. The assay detected pathogenic Leptospira strains, but not intermediately pathogenic or nonpathogenic strains. When testing the assay on spiked clinical specimens, whole blood and plasma were better specimens for detecting the same initial number of leptospires compared with serum from clotted and centrifuged blood. Leptospira spiked at the same concentration was better detected in centrifuged urine. This real-time PCR assay with high specificity and sensitivity may prove to be a rapid method for diagnosing acute leptospirosis.
Passive decoupling of surface coils by pole insertion

Abstract A detailed study is presented of the use of crossed diodes as passive decoupling elements for the isolation of surface coils from whole-body excitation coils. The method involves the insertion of an impedance pole at the resonant condition when the diodes fire. Two microwave diode types have been found particularly effective at 63.8 MHz. Passive decoupling is a particularly attractive method when the coupling between the transmission line and the surface coil is inductive.
Application of molecular topology to quantitative structure‐biodegradability relationships

Simple and multiple linear regressions were applied to the development of models for predicting biodegradability of chemicals from molecular connectivity indexes. Indexes were calculated using the program CFUNC, on the DECsystem 10 computer at the National Institutes of Health, Bethesda, Maryland. Biodegradation data from test systems containing natural media or inocula were obtained from the literature for several homologous series of organic compounds; within each series, all compounds had been tested under the same conditions. The following one-variable models were among those obtained: for 2,4-D alkyl esters, log rate constant versus 2Xv, r2 = 0.954 (n = 6); for N-3-chlorophenylcarbamates, log percent degraded versus 4Xp/c, r2 = 0.971 (n = 7); for dialkyl ethers, log percent theoretical oxygen demand (%ThOD) versus 2Xv, r2 = 0.974 (n = 6); for dialkyl phthalate esters, rate constant versus 2X, r2 = 0.938 (n = 12); for aliphatic acids, %ThOD versus 4Xc, r2 = 0.895 (n = 10). Two-variable models substantially improved results for aliphatic alcohols and acids. These results indicate that the apparent effect of alkyl chain branching on biodegradability can be quantitatively described by connectivity indexes, especially 2X, 3Xc, 4Xc and 4Xp/c, 3Xp also appeared frequently, especially in two-variable models, suggesting a possible role for molecular shape as a determinant of biodegradability. The results suggest that molecular topology holds promise for future research in quantitative structure-biodegradability relationships.
The role of computational science in energy efficiency and renewable energy

The National Renewable Energy Laboratory (NREL) in Golden, Colorado is the nation's premier laboratory for renewable energy and energy efficiency research. The laboratory's mission is to develop renewable energy and energy efficiency technologies and practices and advance related science and engineering to address the nation's energy and environmental goals. A new computational sciences initiative at NREL seeks to dramatically increase the computational expertise and capabilities of the Lab. Integrating numerical simulation and information technology into the laboratory research agenda presents unique challenges and opportunities. In this talk we will discuss the wide variety of scientific research being pursued at the laboratory and the role that computational science can play in helping to improve energy efficiency research and to dramatically reduce the cost of exploiting renewable energy technologies. This talk will also discuss challenges faced in developing large numerical applications for parallel high performance computing systems and architectural support for numerical methods of choice. NREL's web page is: http://www.nrel.gov/ .
Effect of trichloroethylene on DNA methylation and expression of early-intermediate protooncogenes in the liver of B6C3F1 mice.

Trichloroethylene (TCE) is a multimedia environmental pollution that is carcinogenic in mouse liver. The ability of TCE to modulate DNA methylation and the expression of immediate-early protooncogenes was evaluated. Female B6C3F1 mice were administered 1000 mg/kg TCE by gavage 5 days/week and killed after 5, 12, or 33 days of exposure. Methylation of DNA as 5-methylcytosine was decreased by 5 days of treatment with TCE and remained reduced for 33 days. TCE also decreased the methylation of the promoter regions for the protooncogenes, c-jun and c-myc. The expression of the mRNA for the two protooncogenes was increased between 60 and 120 minutes after administering the last dose of TCE and returned to control level by 24 hours. The expression of the mRNA for c-fos remained undetectable after administering TCE. Hence, TCE decreased the methylation both of total DNA and the promoters for the c-jun and c-myc genes and increased the expression of their mRNA. The decreased methylation and increased expression of the two immediate-early protooncogenes might be associated with TCE-induced increase in cell proliferation and promotion of tumors. © 1999 John Wiley & Sons, Inc. J Biochem Toxicol 13: 231–237, 1999
Ultrabroad bandwidth signal generation based on frequency-to-time mapping in the temporal Fresnel regime

It is very well known that ultrashort optical pulses spread by linear propagation in a dispersive medium due to the fact that each spectral component experiences a different group velocity. The so-called frequency-to-time mapping phenomenon establishes that, after sufficient dispersion, the output intensity profile is given by a scaled replica of the optical spectrum of the pulse [1]. This technique is becoming increasingly popular in areas as diverse as ultrafast spectroscopy [2], imaging [3], or electrical arbitrary waveform generation (E- AWG) [4], among others.
Plasma Kallikrein Activation and Inhibition during Typhoid Fever

As an ancillary part of a typhoid fever vaccine study, 10 healthy adult male volunteers (nonimmunized controls) were serially bled 6 days before to 30 days after ingesting 10(5)Salmonella typhi organisms. Five persons developed typhoid fever 6-10 days after challenge, while five remained well. During the febrile illness, significant changes (P < 0.05) in the following hematological parameters were measured: a rise in alpha(1)-antitrypsin antigen concentration and high molecular weight kininogen clotting activity; a progressive decrease of platelet count (to 60% of the predisease state), functional prekallikrein (55%) and kallikrein inhibitor (47%) with a nadir reached on day 5 of the fever and a subsequent overshoot during convalescence. Despite the drop in functional prekallikrein and kallikrein inhibitor, there was no change in factor XII clotting activity or antigenic concentrations of prekallikrein and the kallikrein inhibitors, C1 esterase inhibitor (C1-INH) and alpha(2)-macroglobulin. Plasma from febrile patients subjected to immunoelectrophoresis and crossed immunoelectrophoresis contained a new complex displaying antigenic characteristics of both prekallikrein and C1-INH; the alpha(2)-macroglobulin, antithrombin III, and alpha(1)-antitrypsin immunoprecipitates were unchanged. Plasma drawn from infected-well subjects showed no significant change in these components of the kinin generating system. The finding of a reduction in functional prekallikrein and kallikrein inhibitor (C1-INH) and the formation of a kallikrein C1-INH complex is consistent with prekallikrein activation in typhoid fever. The correlation of these changes with the drop in platelet count suggests that a common mechanism may be responsible.
Multiple-rate structured vector quantization of image pyramids

Abstract A recently introduced tree growth algorithm, the marginal returns algorithm, is used to grow multiple-rate tree-structured vector quantizers for the pyramid coding of rectangularly as well as hexagonally sampled images. The use of a structured multirate codebook solves two problems that normally arise in vector quantization of subbands. The multiple-rate codebook can operate over a wide range of rates, thus dispensing with the need to transmit the codebook as overhead, while the tree structure reduces the search complexity. Search complexity is a crucial issue even in low-rate pyramid coding since subbands with more information content are coded at high rates. In addition, the design technique makes it possible to tune the coder to the spectral properties of the image by optimally allocating rate to the different subbands. It has been shown in an earlier paper that the marginal returns algorithm yields codebooks that are optimal for sources that meet the law of diminishing marginal returns. However, even for sources that do not satisfy these conditions, the algorithm gives coders that perform close to the optional. Image coding results at rates below 1 bit per pixel are presented.
The effect of hold-time on fatigue crack growth behaviors of WASPALOY alloy at elevated temperature

Abstract The effect of hold-time on fatigue crack growth behaviors of WASPALOY alloy was investigated. It was found that the role of hold-time depends on the competition between the harmful environmental effect and the beneficial effect of creep. If temperature is not higher than 705 °C, fatigue crack growth rate of WASPALOY alloy increases with hold-time. On the contrary, hold-time plays a beneficial role on steady state fatigue crack growth of WASPALOY alloy at 760 °C and lower stress intensity factor. The beneficial effect of hold-time was attributed to the creep caused stress relaxation during the hold-time. However, accumulated creep damages cause to cavity nucleation and growth at the grain boundaries, and then accelerate fatigue crack growth. Hold-time plays a harmful role during the final stage of fatigue crack growth.
A three-dimensional equivalent domain integral method for cracked solids

Three-dimensional FEM analysis is presently undertaken via the general formulation of the equivalent-domain integral method for mixed-mode fracture problems in general anisotropic and nonlinear materials. In mixed-mode integrals, the total J-integral is split into three separate modes of fracture; direct and decomposition methods are effective in this separation of the modes, as presently demonstrated by their application to several pure and mixed-mode fracture problems. The results are found to agree well with those reported in the literature, and suggest the usefulness of the method as a FEM-program postprocessing subroutines.
An investigation of axial dispersion enhanced by thermosolutal natural convection in a horizontal annular-like enclosure

Abstract The objective of the experimental investigation was to quantify the axial dispersion of a dilute secondary gas that was subjected to orthogonal thermal and solutal buoyancy gradients in a horizontal annular-like enclosure. Test results showed that a linear axial concentration profile existed at steady-state for the secondary gas. Unheated tests with only solutal buoyancy gradients resulted in a dispersion multiple, D M , of approximately 8 times molecular diffusion. The combined thermal and solutal buoyancy tests, in which a thermal plume from the simulated heater packages aided in mixing, yielded an axial dispersion multiple coefficient of approximately 23 times molecular diffusion, a 188% increase as compared to solutal buoyancy alone. A correlation describing the experimental data trend for the dispersion multiple as a function of buoyancy ratio, N = Ra S / Ra T , was computed to be D M = 19.2 N −0.061 , which is valid for for binary mixtures where the solutal and thermal gradients are orthogonal with Pr and Le of order 1, 0 Ra T 6 , and 0.1 N
Increasing a mildly retarded woman's attendance at self-help classes by overcorrection and instruction*

A mildly retarded female exit-ward resident did not attend special self-care classes designed to prepare her for community placement. An overcorrection procedure was used to increase daily attendance to a grooming class. Overcorrection required the woman to groom four profoundly retarded females, one each half hour, when she did not attend the 2-hr class. After each half hour, the woman was given her choice of attending class or grooming another resident. The woman's attendance increased from a baseline level of 22 to 100% after 1 month of overcorrection, where it remained throughout the study. The woman's attendance at a special education class remained sporadic (mean=32%) until the seventh week of overcorrection for not attending grooming class, when she was told that if she failed to attend the special education classes she would be required to tutor lower functioning students. Thereafter, she had perfect attendance without implementing overcorrection for nonattendance.
Selection criteria for treatment of rectal cancer with combined external and endocavitary radiation.

PURPOSE: The aim of this study was to identify factors predictive of recurrence of rectal tumors treated with combined external and endocavitary radiation. METHODS: Seventy-two patients with rectal cancer were evaluated clinically and with transrectal ultrasound before combined external and endocavitary radiation. Ideal lesions were moderately differentiated, mobile, not ulcerated, <3 cm in diameter, and <12 cm from the anal verge. External radiation (4,500 cGy) was given during five weeks followed by endocavitary radiation (3,000 cGy × 2). Median follow-up was 31 (range, 7–93) months. RESULTS: Pretreatment transrectal ultrasound stages were uT1 (6 patients), uT2(27 patients), and uT3 (39 patients). Clinical evaluation identified 26 ideal and 46 nonideal tumors. Overall recurrence was 36 percent; mean time to recurrence was 12 months. Ideal lesions recurred less than nonideal (15vs. 48 percent;P=0.01). Mobile lesions recurred less than tethered lesions (26vs. 52 percent;P=0.048). Transrectal ultrasound stage was predictive of recurrence (0 percent uT1, 22 percent uT2, and 51 percent uT3;P=0.015). Surgery was possible in 14 of 17 patients with pelvic recurrence only; 11 patients (65 percent) had curative surgery. Distant metastases occurred in nine patients; all had pelvic recurrences, and six died of disease. CONCLUSION: Patients with uT3 or nonideal rectal cancers should not be offered combined external and endocavitary radiation for cure. Transrectal ultrasound stage is the only independent predictor of recurrence.