cssi/SciSciGPT-SciSciNet huggingface dataset:
35 GHz ENDOR characterization of the "very rapid" signal of xanthine oxidase reacted with 2-hydroxy-6-methylpurine (13C8): evidence against direct Mo-C8 interaction.

Xanthine oxidase is a molybdenum-containing enzyme that catalyzes the hydroxylation of xanthine and a wide variety of other aromatic heterocycles. In the course of the reaction with xanthine and substrates such as 2-hydroxy-6-methylpurine (HMP), the enzyme gives rise to a Mo(V) EPR signal, denoted "very rapid", that arises from an authentic catalytic intermediate. The two alternative catalytic mechanisms proposed for this enzyme differ critically in whether the distance between Mo and C8 of the purine nucleus in this intermediate is short enough to admit a direct bonding interaction. To examine this distance, we have performed 13C ENDOR measurements of the "very rapid" EPR signal generated by xanthine oxidase during reaction with 13C8-HMP. The resulting (13)C8 hyperfine tensor, A = [10.2(1), 7.0(1), 6.5(1)] MHz, is discussed in the framework of a detailed consideration of factors involved in extracting metrical parameters from an anisotropic hyperfine interaction composed of contributions from multiple sources, in particular, the effect of the local contributions from spin density on (13)C8. The analysis presented here gives a Mo...C distance whose value is expected to be ca. 2.7-2.9 A in the "very rapid" intermediates formed with both xanthine and HMP, consistent with plausible bond lengths for a Mo-O-C8 fragment where C8 is a trigonal-planar aromatic carbon. The difference from earlier conclusions is explained. The data thus do not support the existence of a direct Mo-C bond in the signal-giving species. This conclusion supports a mechanism that does not involve such an interaction and which begins with base-assisted nucleophilic attack of the Mo(VI)-OH group on the C-8 of substrate, with concomitant hydride transfer to the Mo=S group to give Mo(IV)-SH; the EPR-active "very rapid" species then forms by one-electron oxidation and deprotonation to yield the EPR-detectable Mo(V)OS(OR) species. We further discuss the complexities and limitations of the semiempirical method used to arrive at these conclusions.
The singular control problem and approximate solutions

A method is presented which permits the solution of singular control problems by approximating the nonnormal system with a normal system. It is shown that the approximation can be made arbitrarily accurate. The optimal control of the approximate system is then determined and applied to the actual system. Bounds are obtained on the errors in boundary conditions and the degree of suboptimality brought about by the technique. The method is valid for minimum time and minimum fuel problems with linear constant plants. Examples are presented.
Statistical Estimates of Monthly Mean and Interannual Changes of Radiation Fluxes at the Top of the Atmosphere

Abstract Multiple linear regression is used to relate monthly means and year-to-year changes of the monthly mean planetary albedo and infrared flux leaving the atmosphere, as measured by NOAA satellites, to certain meteorological quantities. Physical predictors are selected which are likely to influence cloudiness, such as temperature, relative humidity and wind. Such predictors can be readily obtained from numerical models. Forty-two months of polar orbiter measurements of radiation fluxes and objective analyses from NMC's operational model were related. Continental and oceanic samples were evaluated separately. Checks on the model consisted of independent tests and comparison with estimation of radiation fluxes in which predictors were functions of latitude, longitude and time of year only. Physical predictors are consistently superior, with the single exception of oceanic albedo, where there was little difference. In the case of the infrared flux, 93 and 84% of the variance in the monthly means is expl...
1-d Lipid Bilayers On Nanotube And Nanowire Templates: Properties And Device Applications

One-dimensional nanomaterials present an exciting opportunity for creating functional biologically-inspired structures because they have unique materials properties, dimensions comparable with the typical size of biological assemblies or individual molecules, and geometry suitable for integration into functional devices and assemblies. We have integrated carbon nanotubes and silicon nanowires with phospholipid bilayers in a “one-dimensional lipid bilayer” assembly in which a nanowire or a nanotube is shielded by a continuous fluid lipid membrane. We will discuss the structure and properties of this bio/nanomaterial assembly, as well as its electrochemical characterization and application in bio/nanoelectronic devices utilizing functional membrane proteins.
The Association Between Disaster-Related Experiences and Mental Health Outcomes Among Drug Using African American Hurricane Katrina Evacuees

This article provides a detailed examination of the relationship between disaster-related experiences and mental health outcomes among a sample of drug using African American Hurricane Katrina evacuees. Face-to-face structured interviews were administered to Hurricane Katrina evacuees (n = 350) residing in voucher assisted apartment complexes in Houston, Texas (2006-2007). We use Ordinary Least Squares and logistic regression models to examine both the relevance of disaster-related experiences and the interactive relationships between disaster-related experiences and post-disaster mental health outcomes including psychological distress, severe depression, somatic symptoms, and posttraumatic stress disorder. Results indicate that disaster-related experiences including negative life changes, disaster exposure, post-disaster stressors, and resource loss, have unique, inverse relationships with mental health. While resource loss has the strongest inverse relationship with mental health, disaster exposure has a negative interactive effect on psychological distress and anxiety. Although highly vulnerable populations report low levels of mental health nearly 2 years following a disaster experience, there is a convergence in mental health outcomes with high levels of disaster experiences and disaster exposure that suggests mental resiliency.
Validity and Reliability of Visual Ratings of the Vertical Jump

The validity and reliability of visual estimates of the kinematics of the vertical jump as would be common in qualitative analysis of human movement was studied. Sagittal plane videotapes of 12 females performing vertical jumps were rated on two occasions by three samples of subjects: 6 basketball coaches, 10 kinesiology students, and 5 kinesiology professors. Visual ratings were compared to values quantified by biomechanical analysis using the Peak Performance Technologies system. Assistant collegiate basketball coaches were unable to rate discrete body angles in the vertical jump accurately or consistently. Six of 10 college student raters could accurately and consistently rate over-all range of motion. Since only one of the kinesiology professors could accurately and consistently rate range of motion compared to the majority of the students, professional experience did not affect the ability to rate range of motion in the vertical jump in these subjects.
Living with Republican Party of Minnesota V. White: The birth and death of judicial campaign speech restrictions

In Republican Party of Minnesota v. White, the Supreme Court of the United States declared unconstitutional a Minnesota judicial canon prohibiting judicial candidates from announcing their views on issues likely to come before them. This triggered legal action in other states and a debate not only over speech rights, but over the state of the judiciary as well. With the growing presence of interest groups in judicial elections and increasing campaign spending, it is no surprise that polls show that more than 70% of voters believe money influences judicial decisions. This article examines the history of judicial selection and canons on speech through a lens of First Amendment theory, focusing on practical responses to the precedent set in White. It is critical that states take action to restore public confidence in the independence and impartiality of the courts. Merit selection, campaign finance reform, strict recusal standards and a better informed public are viable alternatives to speech-restricting canons.
An Integrated Virtual Family Curriculum to Introduce Specialty-Specific Clinical Skills to Rising Third-Year Medical Students

Background: Transitioning from a preclinical to a clinical curriculum can be challenging for medical students. As a central component of a new 3-week transition course, we designed, implemented, and evaluated an innovative Virtual Family Curriculum to introduce rising 3rd-year medical students to the knowledge, skills, and cultures of 6 core medical and surgical specialties. Description: The authors designed a 6-case, 24-hour, 3-generation Virtual Family Curriculum and a 6-station summative Objective Structured Clinical Examination (OSCE). Each case contains a lecture, video, discussion questions, skills practice, and faculty guide. We used both qualitative and quantitative evaluation methods. Evaluation: Ninety-eight students took the inaugural course in 2012. All students passed the final OSCE. Students rated the virtual family curriculum a 5.17/6 (6 = highest). Comments about the curriculum were uniformly positive. Conclusions: We created and implemented an integrated Virtual Family Curriculum that sys...
Worldwide Guidelines for the Preparation and Quality Management of Dialysis Fluid and Their Implementation

Quality standards for dialysis water have existed for more than 25 years. Current standards generally agree concerning the maximum allowable levels of chemical contaminants; however, significant differences exist concerning the maximum allowable levels of microbiological contaminants and the methods used to measure them. While quality standards for dialysis water are common, there are relatively few standards or recommendations for dialysis fluid quality and these also differ markedly in the maximum allowable level for microbiological contaminants. Compliance with quality standards for dialysis water and dialysis fluid appears to have improved over the past 20 years, although the actual extent of compliance is difficult to assess. A universal standard for fluid quality might be of benefit to the wider dialysis community; however, progress towards that goal will depend on resolution of important issues, including how the standard is to be applied, if it should be limited to substances with documented toxicity for hemodialysis patients, and how to address microbiological contaminants.
Electronic Student Journals: A Means to Enhance Classroom Communications

Written journals, as a means of enhancing communication between teachers and students, are espoused quite extensively in the literature. But on the university level, where classes do not usually meet every day, the rate of exchange of the journals between an instructor and his or her students can be slowed considerably, thus limiting the benefits usually associated with this form of communication. To increase the exchange rate of journals, it was proposed that electronic mail be utilized as the medium by which the journal entries were transmitted. Eighty students in three sections of a general education required computer literacy course participated in this study. Results from the study found that the students who used electronic journals wrote significantly longer entries than the students who wrote in traditional written journals. No differences were found, though, between treatment groups as to computer-related knowledge and attitudes.
Compositional and kinetic analysis of oil shale pyrolysis using TGA–MS

Abstract There are vast resources of oil shale in the western United States. Development of technically and economically effective technologies for the conversion of oil shale to liquid fuels will help provide a long-term and secure source of transportation fuels. Developing good understanding of the decomposition kinetics of oil shale to oil and other products, along with the oil compositional information are important regardless of the process used. Themogravimetric analysis combined with online mass spectrometry (TGA–MS) affords the opportunity to obtain compositional information while the decomposition is being measured quantitatively. In this work we provide data on the TGA–MS analyses of Green River oil shale from Utah. Compounds of about 300 atomic mass units were targeted in the mass spectrometric analyses. The weight loss results from the TGA part of the analysis and the subsequent kinetic parameters derived from the data were consistent with our prior work. The activation energies of decomposition were in the 90–230 kJ/mol range with respect to conversion with uncertainty numbers of about 10%. Lighter hydrocarbons evolved slightly earlier and their amounts were higher in comparison to heavier hydrocarbons. Alkanes such as hexane and decane were detected at slightly lower temperatures than their equivalent carbon number aromatic compounds, but the differences were not significant. Higher heating rates generated more alkenes compared to respective alkanes and as the carbon number increased, this ratio decreased. Kinetics of the formation of naphtha group of compounds (C5–C12) were derived using the advanced isoconversion method. The activation energies in the range of 41–206 kJ/mol were lower than for the entire decomposition process. However, because the compound evolution signals as detected by mass spectrometry are noisier than the overall weight loss data, the uncertainties in these measurements were much greater in certain conversion ranges. Similar principles can be used to derive single component evolution kinetics.
Task orientation, parental warmth and SES account for a significant proportion of the shared environmental variance in general cognitive ability in early childhood: evidence from a twin study

Prior research suggests shared environmental influences on cognitive performance are important in early childhood. However, few studies have attempted to identify the factors comprising this shared environmental variance. To address this issue, we examined the covariance between task orientation, parental warmth, socioeconomic status and general cognitive ability in a British twin study of 125 pairs of identical and same-sex fraternal twins. Task orientation correlated r =.41 with general cognitive ability Bivariate genetic analyses suggested that this correlation was mediated by shared environmental influences. Additional analyses suggested that SES and parental warmth mediated about two-thirds of the shared environmental covariance between task engagement and cognitive skills.
Optimization of Multi-pass Amplifiers in TW-Class Ti:sapphire Chirped Pulse Amplification Systems

Multi-pass amplifiers are utilized in the upgrade of a Ti:sapphire chirped-pulse amplification system from 300 GW to 10 TW. Several amplifier design techniques are explored to optimize pulse energy and beam quality.
Exercise mitigates the association of abdominal obesity with high-density lipoprotein cholesterol in premenopausal women : Results from the third National Health and Nutrition Examination Survey

Abstract Objective To examine the relationship between abdominal obesity, as measured by waist-to-hip ratio (WHR) and high-density lipoprotein cholesterol (HDL-C) level within the context of age, body fatness, exercise, saturated fat intake, and other plasma lipids. Design/subjects Subjects were premenopausal, white, non-Hispanic women from the third National Health and Nutrition Examination Survey. Smokers, heavy drinkers, and women who took lipid-altering drugs were excluded. Of 1,188 subjects who met the inclusion criteria, complete data were available for 435 women. Statistical analyses Means were calculated using all subjects for each variable, then F-protected t tests and linear contrasts were performed to test differences in means between subgroups. A P Results Age was not significantly associated with HDL-C level. Comparisons of HDL-C by WHR, percentage body fat (%BF), and exercise level revealed that HDL-C level was significantly lower at the higher levels of WHR and %BF and higher at the highest levels of exercise. Higher levels of HDL-C were generally accompanied by lower levels of triacylglycerol. When HDL-C was compared by exercise level within each WHR tertile and %BF tertile, the association of exercise with HDL-C diminished. Saturated fat intake was not associated with HDL-C. Conclusions/applications Increased exercise is associated with a lower WHR and subsequently a higher HDL-C level. This association between WHR and HDL-C appears to be mediated through %BF. Women exercisers with the highest WHR had consistently more favorable plasma lipid profiles and lower mean body mass index and %BF than nonexercisers. Thus, for women who exhibit abdominal obesity, exercise mitigates the association of WHR with HDL-C level. Vigorous exercise in the premenopausal years may promote a more favorable lipid profile, even in the presence of increased body fat and abdominal girth. J Am Diet Assoc. 2000;100: 1347–1353 .
A polyclonal antibody to a synthetic peptide derived from the rat follicle-stimulating hormone receptor reveals the recombinant receptor as a 74-kilodalton protein

We have prepared a polyclonal antibody (AntiF) against a synthetic peptide comprising residues 19-29 of the rat FSH receptor. The specificity of this antibody was documented using human embryonic kidney (293) cells and stable transfectants of 293 cells expressing the recombinant LH/CG and FSH receptors. The data presented show that AntiF inhibits the binding of FSH, but not that of LH/CG, to their cognate receptors. AntiF also recognizes a specific protein(s) representing the FSH receptor in Western blots or by immunoprecipitation of cells transfected with the FSH receptor. This protein(s) is not present in untransfected 293 cells or in 293 cells permanently transfected with the LH/CG receptor. Finally, addition of the 19-29 peptide prevents immunoprecipitation of the FSH receptor by AntiF, whereas an unrelated peptide corresponding to residues 637-647 has no effect. In Western blots of 293 cells transfected with the FSH receptor, AntiF reveals the recombinant receptor as a heterogenous glycoprotein with a molecular mass of 58,000-83,000 daltons (in the absence of thiol-reducing agents) or 69,000-81,000 (in the presence of thiol reducing agents). Pulse-chase experiments with metabolically labeled cells show that the mature FSH receptor is a 74-kilodalton protein derived from 67- and 72-kilodalton precursors.
Enhancing the observability of the Efimov effect in ultracold atomic gas mixtures

We discuss the prospects for observing the characteristic features of the Efimov effect in a two-component ultracold atomic gas near an interspecies Feshbach resonance. In the ultracold regime, the Efimov effect is expected to be manifested in the three-body collision rates through the appearance of series of minima or maxima as a function of the two-body s-wave scattering length a. Here, we propose the observation of this Efimov physics through measurements of the inelastic three-body rate constants near a Feshbach resonance. Our analysis suggests that boson-fermion mixtures, where the bosons are much heavier than the fermions, are the most favorable system to observe such features.
Direct Synthesis of Well-Defined Alcohol-Functionalized Polymers via Acyclic Diene Metathesis (ADMET) Polymerization

Because of its robust nature, Grubbs' ruthenium benzylidene catalyst RuCl2(CHPh)(PCy3)2 promotes the successful acyclic diene metathesis (ADMET) bulk polymerization of alcohol-functionalized dienes, thus providing a method for the direct synthesis of linear polymers containing hydroxy groups. Primary, secondary, and tertiary alcohol functional groups can be placed at precise intervals along an unsaturated hydrocarbon backbone. Exhaustive hydrogenation of the secondary alcohol homologue produces a well-defined ethylenevinyl alcohol copolymer. Only the unsaturated and saturated secondary alcohol polymers crystallize, a phenomenon likely attributed to the enhanced packing propensity of these macromolecules in comparison with those of their primary and tertiary analogues.
Numerical ellipsometry: High accuracy modeling of thin absorbing films in the n–k plane

Abstract A major challenge for those utilizing ellipsometry is numerical processing of the measured data. Our recent work shows how the transcendental, multivalued equations arising from the physics of reflection from layers can be solved in the n – k plane. This approach applies the mathematics of Complex Analysis to solve the equations numerically. The work presented extends the n – k method to obtain solutions within the accuracy limit of each measurement. The system treated here is that of a thin absorbing film (chromium) overlying a known substrate (silicon). Solutions for a three-layer model of the chromium film including film–substrate and film–air interfacial layers result in a mean square error (MSE) on the order of 0.01, a significant improvement over a single-layer model. Relaxing the constraint of vertical homogeneity provides a six-layer model with the same interfacial layers and four sublayers of chromium. The chromium layers have near-identical values of optical properties and an MSE of essentially zero (10 − 13 ). It is anticipated that additional methods will be needed for other classes of problems.
Laser stapedotomy technique

The surgical treatment of otosclerosis has been one of the most successful operations in any surgical field and an exciting chapter in otologic surgical history. The use of the laser to remove the superstructure of the stapes and to create the footplate fenestra represents the latest in the continuum of refinements in making the procedure safer and with reduced morbidity. In laser stapedotomy there are many details and nuances that make the procedure more successful for all levels of technical expertise. This communication describes surgical preparation of the patient and the surgeon, and the operative technique currently employed by the author in the laser stapedotomy procedure. It provides a highly graphic depiction of the steps in the procedure along with a description of specific instrumentation employed in each step. Management of special circumstances such as overhanging facial nerve, narrow niche, obliterated and floating footplates are discussed.
Endovascular Model of Rabbit Hindlimb Ischemia: A Platform to Evaluate Therapeutic Angiogenesis

PURPOSE Current animal hindlimb ischemia models involve surgical ligation of the femoral artery and delivery of therapeutic angiogenic agents into the adductor compartment. The authors hypothesize that an endovascular model of hindlimb ischemia would be a more appropriate platform, closely resembling atherosclerosis by occluding the vessel from within, causing less inflammation, wound healing and subsequent collateralization. MATERIALS AND METHODS The left superficial femoral artery in 17 rabbits was occluded by endovascular coil embolization ( n = 9) or surgical ligation ( n = 8). Animals ( n = 3; in each group) were sacrificed on day 3 to determine the arteriolar luminal area, number of arterioles, microsphere determined perfusion, and degree of inflammation. On day 28, the remaining animals underwent calf blood pressure measurements and angiography to determine the number of collaterals and diameter of vessels supplying the hindlimb. RESULTS Immediate postprocedure (day 0) and presacrifice (day 3 or 28) occlusion rates were 89% (eight of nine rabbits) and 100% for the endovascular model; 100% and 100% for the surgical model, respectively. Hindlimb paralysis and muscle atrophy was found in one surgical animal. On day 3, there was an increase in hindlimb perfusion (surgery, 0.04 ± 0.01; endovascular, 0.02 ± 0.01; P = .02), an increase in arteriolar luminal area (surgery, 481 μm ± 240; endovascular, 345 μm ± 151; P = .04), and a trend toward more inflammation (surgery, 5.5 ± 3.8; endovascular, 2.5 ± 3.0; P = .08) in the surgical group. There was no difference in number of vessels between both groups. On day 28 there was no difference in the calf blood pressure ratios or in the number of collaterals. However, there was enlargement of the distal profunda femoris artery, the vessel closest to the surgical incision, in the surgical group (L/R ratio: immediate post-occlusion, 1.06 ± 0.11; day 28, 1.27 ± 0.08; P = .02). CONCLUSION The endovascular model was efficacious in providing occlusion of the superficial femoral artery, and induced less of an arteriogenic response compared with the surgical model. The authors believe that this endovascular model is a superior platform for studying therapeutic angiogenic agents.
X-ray absorption spectroscopy with polarized synchrotron radiation

X-ray absorption spectroscopy based on the polarized nature of synchrotron radiation is considered. It is concluded that linearly polarized radiation can be used for studying the anisotropic nature of electronic and atomic structure by measuring X-ray absorption near edge structure and extended X-ray absorption fine structure spectra of single crystals or oriented powders. Circularly polarized radiation can be used for studying the spin density of final electronic states in a magnetic system. Particular attention is given to experimental results on absorption of linearly polarized radiation through a highly anisotropic medium of oriented copper oxides at the Cu K-edge.
Spectral refractive index and extinction cross-section of BG spores

Despite the wide spread need for optical cross-section data on single spore bio-aerosols, available databases are sparse and unreliable. Information reported is based on short path measurements on high concentration media containing particle clusters. This represents an upper bound to the single spore cross-section. Measurements on single spore aerosolized media demand long path lengths and moderate particle concentration. Transmittance measurements need to be in the single scatter limit as well. These requirements are often difficult to meet. We present a procedure that leads to aerosol extinction and backscatter cross-sections in a straightforward manner. Transmittance measurements of thin films of bio-aerosols are used to obtain the bulk refractive index. This result and the measured size distribution can be used in a T-matrix calculation to yield the desired cross-sections. To illustrate this technique, infrared cross-sections are obtained for Bacillus globigii.
Carbon nanofiber based buckypaper used as a thermal interface material

Carbon nanofiber (CNF) based buckypaper was explored as a potential thermal interface material (TIM) for electronics. CNFs were subjected to heat treatment temperatures of 1100 °C, 1500 °C and 3000 °C. TIMs were prepared and characterized using thermal impedance test stand. Results show that the thermal impedance at the interface decreased in conjunction with the increasing heat-treatment temperature of CNFs. TIMs with graphitized CNF exhibit a significant decrease of 54% in thermal impedance in comparison with the dry contact. This improvement is likely due to the high degree of CNF graphitizibility and the resulting outstanding electrical and thermal conductivities.
A utility accrual scheduling algorithm for real-time activities with mutual exclusion resource constraints

This paper presents a uni-processor real-time scheduling algorithm called the generic utility scheduling algorithm (which we refer to simply as GUS). GUS solves a previously open real-time scheduling problem-scheduling application activities that have time constraints specified using arbitrarily shaped time/utility functions and have mutual exclusion resource constraints. A time/ utility function are a time constraint specification that describes an activity's utility to the system as a function of that activity's completion time. Given such time and resource constraints, we consider the scheduling objective of maximizing the total utility that is accrued by the completion of all activities. Since this problem is NP-hard, GUS heuristically computes schedules with a polynomial-time cost of O(n/sup 3/) at each scheduling event, where n is the number of activities in the ready queue. We evaluate the performance of GUS through simulation and by an actual implementation on a real-time POSIX operating system. Our simulation studies and implementation measurements reveal that GUS performs close to, if not better than, the existing algorithms for the cases that they apply. Furthermore, we analytically establish several properties of GUS.
Antimicrobial nanotechnology: its potential for the effective management of microbial drug resistance and implications for research needs in microbial nanotoxicology

The development of antibiotics revolutionized human health, providing a simple cure for once dreaded diseases such as tuberculosis. However, widespread production, use, and mis-use of antibiotics have contributed to the next-generation concern for global public health: the emergence of multiple drug-resistant (MDR) infectious organisms (a.k.a. “superbugs”). Recently, nanotechnology, specifically the use of nanomaterials (NMs) with antimicrobial activity, has been presented as a new defense against MDR infectious organisms. We discuss the potential for NMs to either circumvent microbial resistance or induce its development in light of our current state of knowledge, finding that this question points to a need for fundamental research targeting the molecular mechanisms causing antimicrobial activity in NMs. In the context of current microbial nanotoxicology studies, particularly reductionist laboratory studies, we offer suggestions and considerations for future research, using an illustrative example from our work with silver nanoparticles.
Resilience in developing systems: Progress and promise as the fourth wave rises

Perspectives based on the first three waves of resilience research are discussed with the goal of informing the fourth wave of work, which is characterized by a focus on multilevel analysis and the dynamics of adaptation and change. Resilience is defined as a broad systems construct, referring to the capacity of dynamic systems to withstand or recover from significant disturbances. As the systems perspective on resilience builds strength and technologies of measuring and analyzing multiple levels of functioning and their interactions improve, it is becoming feasible to study gene-environment interactions, the development of adaptive systems and their role in resilience, and to conduct experiments to foster resilience or reprogram the fundamental adaptive systems that protect development in the context of adversity. Hot spots for future research to study and integrate multiple levels of analysis are delineated on the basis of evidence gleaned from the first waves of resilience research.
Understanding Risk Communication Through Patient Narratives About Complex Antithrombotic Therapies

The purpose of this study was to explore how patients use narratives to create coherent understandings of risks associated with complex antithrombotic therapies. We led four focus groups consisting of patients older than 65 years of age who had a diagnosis of cardiovascular disease and were using a prescription for cardioprotective agents, such as aspirin, anticoagulants, and/or antiplatelets. The participants' stories were retrospective accounts about physician and patient interactions and adverse events organized in the plot structure of a trial-and-error story. The trial-and-error narrative structure emphasizes patients' idiosyncrasies and reasons why they expect to experience adverse events from changes in treatment. Any fears that they might have had about these risks were mitigated by physician expertise, patient responsibility, and medical technology. Patients who expressed concern about not having sufficient access to medical expertise (e.g., physicians, laboratory tests) seemed less willing to accept risks. The trial-and-error risk narratives helped patients deal with ambiguity and uncertainty about the outcomes of their therapies, and revealed patients' orientations to the risks they faced.
Use of Topical Tranexamic Acid or Aminocaproic Acid to Prevent Bleeding After Major Surgical Procedures

OBJECTIVE:To evaluate the literature describing topical use of tranexamic acid or aminocaproic acid for prevention of postoperative bleeding after major surgical procedures.DATA SOURCES:Literature was retrieved through MEDLINE (1946-September 2011) and International Pharmaceutical Abstracts(1970-September 2011) using the terms tranexamic acid, aminocaproic acid, antifibrinolytic, topical, and surgical. In addition, reference citations from publications identified were reviewed.STUDY SELECTION AND DATA EXTRACTION:All identified articles in English were evaluated. Clinical trials, case reports, and meta-analyses describing topical use of tranexamic acid or aminocaproic acid to prevent postoperative bleeding were included.DATA SYNTHESIS:A total of 16 publications in the setting of major surgical procedures were included; the majority of data were for tranexamic acid. For cardiac surgery, 4 trials used solutions containing tranexamic acid (1-2.5 g in 100-250 mL of 0.9% NaCl), and 1 trial assessed a solution c...
High-Pressure Processing of Orange Juice: Kinetics of Pectinmethylesterase Inactivation

A kinetic study of pectinmethylesterase (PME) inactivation in orange juice was conducted. Juice samples were subjected to combinations of high pressure (400, 500, 600 MPa) and thermal (25, 37.5, 50 C) treatments for various time periods. PME inactivation followed a first-order kinetic model with a residual activity of pressure- resistant enzyme remaining. Calculated D-values ranged from 4.6 min to 117.5 min at 600 MPa/50 C and 400 MPa/25 C, respectively. Pressures in excess of 500 MPa resulted in sufficiently fast inactivation rates for economic viability of the process.
Sloshing of liquids in cylindrical tanks

Introduction T sloshing frequencies of liquids in cylindrical tanks are important design parameters for aircraft and space vehicles. For instance, launch vehicles have an enormous percentage of their initial weight as fuel; consequently, the dynamic forces resulting from the motions of these large liquid masses can be substantial even to the point of exceeding the ability of the control system to counteract them or of the structure to resist them. In order to obtain good estimates of the magnitude of the forces generated by possible couplings between the control system, the structural frame, and the sloshing fuel, it is desirable to know the natural frequencies of the system as accurately as possible. In this Note, we discuss a method recently developed by the authors that leads to a simple but effective procedure for estimating the sloshing frequencies with rigorous error bounds. An important previous contribution to this problem was made by Budiansky, who used conformal mapping to formulate the problem as an integral equation which he then discretized. Out calculations improve his results.
A Novel Role for the Marrow Microenvironment in Initiating and Sustaining Hematopoietic Disease

Background: The marrow microenvironment is composed of a complex network of cells and extra cellular matrix that cooperate to regulate normal hematopoiesis. There is growing evidence that microenvironmental defects can contribute to the pathogenesis of hematological malignancies. Objective/methods: We review the role of the microenvironment in inducing and sustaining hematological malignancies. Results/conclusions: Two basic mechanisms could explain the role of microenvironmental defects in the evolution of hematopoietic neoplasms. There is significant data to support the first mechanism, in which the malignant hematopoietic clone induces reversible functional changes in the microenvironment that result in improved growth conditions for the malignant cells. More recent studies from mouse models have indicated that a second mechanism involving primary microenvironmental defects can also result in malignancy.
Concomitant Visual Stimulation Does Not Alter Habituation of Nystagmic, Oculogyral Or Psychophysical Responses to Angular Acceleration

This experiment evaluated the influence of various types of visual stimulation upon the habituation of nystagmic, oculogyral, and psychophysical responses to angular acceleration. Four groups of 20 young men each were given a series of 16 angular accelerations of 24°/sec2 magnitude and of 10-scc duration. Concomitant visual stimulation, varied between groups from total darkness to full room illumination, was introduced on habituation trials that were interpolated between test trials. Although highly significant decrements for all responses were found with repeated testing, the different visual conditions in no way altered this habituation.
The magnetic and electronic structure of vanadyl pyrophosphate from density functional theory.

We have studied the magnetic structure of the high symmetry vanadyl pyrophosphate ((VO)2P2O7, VOPO), focusing on the spin exchange couplings, using density functional theory (B3LYP) with the full three-dimensional periodicity. VOPO involves four distinct spin couplings: two larger couplings exist along the chain direction (a-axis), which we predict to be antiferromagnetic, JOPO = −156.8 K and JO = −68.6 K, and two weaker couplings appear along the c (between two layers) and b directions (between two chains in the same layer), which we calculate to be ferromagnetic, Jlayer = 19.2 K and Jchain = 2.8 K. Based on the local density of states and the response of spin couplings to varying the cell parameter a, we found that JOPO originates from a super-exchange interaction through the bridging –O–P–O– unit. In contrast, JO results from a direct overlap of 3dx2 − y2 orbitals on two vanadium atoms in the same V2O8 motif, making it very sensitive to structural fluctuations. Based on the variations in V–O bond length as a function of strain along a, we found that the V–O bonds of V–(OPO)2–V are covalent and rigid, whereas the bonds of V–(O)2–V are fragile and dative. These distinctions suggest that compression along the a-axis would have a dramatic impact on JO, changing the magnetic structure and spin gap of VOPO. This result also suggests that assuming JO to be a constant over the range of 2–300 K whilst fitting couplings to the experimental magnetic susceptibility is an invalid method. Regarding its role as a catalyst, the bonding pattern suggests that O2 can penetrate beyond the top layers of the VOPO surface, converting multiple V atoms from the +4 to +5 oxidation state, which seems crucial to explain the deep oxidation of n-butane to maleic anhydride.
In Situ Identification of Crystals on Process Cheese by X-ray Diffraction

Abstract A rapid and accurate method for in situ identification of crystals on process cheese has been developed using X-ray diffraction. Sufficient crystals were developed on process cheeses made with 3.0% anhydrous trisodium phosphate as the emulsifier and 2.0% sodium chloride. Discs of cheese containing crystals are mounted in the X-ray specimen holder and are placed in the diffractometer for direct analysis. Diffraction patterns from crystals in situ and crystals mulled in Nujol were nearly identical and corresponded with the ASTM index card for the α-form of disodium phosphate dodecahydrate. Phosphorus content and ignition losses of crystals from cheese correspond very closely to the theoretical values for disodium phosphate dodecahydrate.
Free-Space Optical Link as a Model Undergraduate Design Project

An undergraduate design project is described in which a free-space optical communications link is constructed. The interest and motivation for the students is achieved by using a visible laser and constructing a complete system by using the digital output of a CD/DVD player and an audio receiver to transmit music over the free-space link. In addition to providing a high-level technical experience, the project also teaches multidisciplinary teamwork and emulates a real working environment; it is relatively low cost, divisible into modules, and adaptable. An overview of the project is included with representative designs and information.
How and Why US Health Care Differs From That in Other OECD Countries

UNITED STATES HEALTH CARE, OFTEN HAILED AS “THE best health care system in the world,” is also faulted for being too costly, leaving many millions of individuals uninsured, and having avoidable lapses in quality. Criticism often draws on comparisons with other countries of the Organization for Economic Co-operation and Development (OECD). This Viewpoint also makes such comparisons, over a broad range of variables, and reaches one inescapable conclusion—US health care is very different from health care in other countries. Potential reasons for the differences are discussed, leading to the conclusion that future efforts to control cost, provide universal coverage, and improve health outcomes will have to consider the United States’ particular history, values, and political system.
Developmental differences in interactional characteristics of mothers and their children with failure to thrive

Observed interactional characteristics during feeding sessions among 68 pairs of low-income mother-child dyads. Half of the children were experiencing non-organic failure to thrive (NOFTT) and half were growing adequately. Children were spoon-fed and ranged in age from 8 to 26 months. Across NOFTT and comparison groups, toddlers (13.5 to 26 months) were perceived by their mothers as more difficult than were infants (8 to 13.4 months). Although there were few differences between the NOFTT and comparison groups on interactional characteristics overall, mothers of NOFTT toddlers were more hostile, intrusive, and less flexible than mothers of NOFTT infants and there was more tension and anger in their interactions. Maternal behavior did not differ among the comparison group. Mothers of NOFTT children may experience difficulties in responding to the increasing demands for autonomy during feeding among toddlers. Finally, when the interaction was observed in dyadic terms, toddlers in both groups tended to be more active and involved than infants.
An ensemble of models of the acute inflammatory response to bacterial lipopolysaccharide in rats: Results from parameter space reduction

In previous work, we developed an 8-state nonlinear dynamic model of the acute inflammatory response, including activated phagocytic cells, pro- and anti-inflammatory cytokines, and tissue damage, and calibrated it to data on cytokines from endotoxemic rats. In the interest of parsimony, the present work employed parametric sensitivity and local identifiability analysis to establish a core set of parameters predominantly responsible for variability in model solutions. Parameter optimization, facilitated by varying only those parameters belonging to this core set, was used to identify an ensemble of parameter vectors, each representing an acceptable local optimum in terms of fit to experimental data. Individual models within this ensemble, characterized by their different parameter values, showed similar cytokine but diverse tissue damage behavior. A cluster analysis of the ensemble of models showed the existence of a continuum of acceptable models, characterized by compensatory mechanisms and parameter changes. We calculated the direct correlations between the core set of model parameters and identified three mechanisms responsible for the conversion of the diverse damage time courses to similar cytokine behavior in these models. Given that tissue damage level could be an indicator of the likelihood of mortality, our findings suggest that similar cytokine dynamics could be associated with very different mortality outcomes, depending on the balance of certain inflammatory elements.
Searching and Ranking Documents based on Semantic Relationships

Just as the link structure of the web is a critical component in today's web search, complex relationships (i.e., the different ways the dots are connected) will be an important component in tomorrow's web search technologies. In this paper, I summarize my research on answering the question of: How we can exploit semantic relationships of named-entities to improve relevance in search and ranking of documents? The intuition of my approach is to first analyze the relationships of namedentities with respect to a query. Second, relevance weights, which are assigned by human experts, can then be used to guarantee results within a relevance threshold. These relevance measures can be applied both for searching and ranking of documents.
Pediatric acute respiratory failure: areas of debate in the pediatric critical care setting

Pediatric intensive care units across the world care for large numbers of mechanically ventilated infants and children on a daily basis, yet management of these patients is far from standardized. This lack of standardization may be a necessity in certain situations given variation between underlying disease processes, pathophysiology, response to therapy and available resources. However, there are many situations in which similar patients are managed differently across pediatric intensive care units simply because there are a shortage of available data to guide the management of these critically ill infants and children. Thus, a large fraction of pediatric critical care involves a combination of institutional preference, individual experience, opinion and extrapolation of adult data.
Techniques and complications of ileostomy takedown

Abstract Objective: We use a loop ileostomy for temporary fecal diversion because of ease of technical construction and assumed low complication rate. Here, we review our complications of loop ileostomy and takedown using three techniques of closure. Methods: We reviewed charts of all patients who had temporary ileostomies constructed during 1987 to 1995 (n = 366). Ileostomy takedown was performed in 339 patients using one of three closure techniques: enterotomy suture (65%), resection with handsewn anastomosis (20%), and stapled anastomosis (15%). Complications were recorded for pre-takedown and 30-day post-takedown intervals. Results: Overall complication rate was 28%. Pre-takedown complications occurred in 21 patients (5.7%), including small bowel obstruction (2.5%) and dehydration/electrolyte derangement (2.2%). Post-takedown complications occurred in 83 patients (24.5%), including wound infection (14.2%), small bowel obstruction (5%), anastomotic leak (2.9%), and 1 death from a cardiac event. Post-takedown obstruction was higher for closure using resection with sutured anastomosis (12%) compared with enterotomy suture (2.3%), P ≤0.003. Stapled anastomosis had an intermediate rate of obstruction (7.7%). Anastomotic leak was similar between closure techniques. Conclusions: Loop ileostomy and takedown are associated with low rates of serious complications (5% or less). As such, we continue to advocate use of loop ileostomy as a diversion procedure. Closure by enterotomy suture is preferred over resection. However, if resection is required, closure by stapled anastomosis is preferred over suture anastomosis.
Replication from oriP of Epstein-Barr virus requires human ORC and is inhibited by geminin.

Abstract A hypomorphic mutation made in the ORC2 gene of a human cancer cell line through homologous recombination decreased Orc2 protein levels by 90%. The G1 phase of the cell cycle was prolonged, but there was no effect on the utilization of either the c-Myc or β-globin cellular origins of replication. Cells carrying this mutation failed to support the replication of a plasmid bearing the oriP replicator of Epstein Barr virus (EBV), and this defect was rescued by reintroduction of Orc2. Orc2 specifically associates with oriP in cells, most likely through its interaction with EBNA1. Geminin, an inhibitor of the mammalian replication initiation complex, inhibits replication from oriP. Therefore, ORC and the human replication initiation apparatus is required for replication from a viral origin of replication.