cssi/SciSciGPT-SciSciNet huggingface dataset:
A Model for Binary Time Series Data with Serial Odds Ratio Patterns

SUMMARY Moment methods for analysing repeated binary responses using the marginal odds ratio as a measure of association have recently been proposed by several researchers. Using the generalized estimating equation (GEE) methodology, they estimated the regression parameters associated with the expected value of an individual's vector of binary responses. In addition, they estimated the marginal odds ratio between pairs of binary responses. In this paper, we discuss a model for binary time series data where the repeated responses on each individual may be unequally spaced in time. This model allows both the number of observations per individual and the times of measurement to vary between individuals. Our approach is to model the association between the binary responses using serial odds ratio patterns. This model can be thought of as a binary time series analogue of the exponential correlation pattern so commonly assumed for continuous time series data. Parameter estimates are obtained by using the GEE methodology. The model is illustrated with data from an arthritis clinical trial where the response variable is a binary self-assessment measurement.
Combined Transplantation of Adult and Fetal Islets for Improvement of Graft Function: Prospective Approach for Diabetes Treatment

The major threat of diabetes mellitus is the progressive development of debilitating complications. Current treatment modalities remain suboptimal as evidenced by persistent, significant morbidity and mortality (1,2). More than twenty years ago, our group pioneered fetal pancreatic islet transplantation for treatment of type 1 diabetes (3). Our working hypothesis has been that diabetic complications can be prevented if blood glucose levels are tightly controlled by physiological mechanisms. The lessons we have learned from the Diabetes Control and Complications Trial (4) support this hypothesis. The islets of Langerhans isolated from the pancreas can be transplanted into diabetic patients with a minimally invasive technique. The transplanted islets release insulin in response to high glucose stimuli by homeostatic mechanisms and thus can provide the best control of blood glucose (5). Furthermore, successful islet transplantation will free the patients from the repeated blood glucose monitoring, insulin injections, and improve the quality of life. In order to achieve this goal, pancreatic islet transplantation must ultimately fulfill the following three requirements: Transplanted islets 1) will have their effect on hyperglycemia soon after transplantation, 2) will provide long-lasting insulin independence, preferably life-time, and 3) will survive without continuous use of immunosuppressive agents.
Key Factors in Understanding Trends in Hollywood Product Placements from 2005 to 2015

This study updates extant product placement research by identifying the evolutions in product placements between 2005 and 2015 in top grossing Hollywood films. Using a quantitative content analysis...
L. DiAnne Borders: Leadership Through Mentorship and Modeling

Dr. L. DiAnne Borders has profoundly impacted professional counseling and counselor education, particularly in areas of scholarship and clinical supervision. In this leadership profile, the authors...
The ethics of commercial human smuggling

Even though human smuggling is one of the central topics of contention in the political discourse about immigration, it has received virtually no attention from moral philosophy. This article aims ...
The Use and Method of Action of Intravenous Lidocaine and Its Metabolite in Headache Disorders.

Background Lidocaine, an amide anesthetic, has been used in the treatment of a wide variety of pain disorders for over 75 years. In addition to pain control, lidocaine is an anti-arrhythmic agent and has anti-inflammatory properties. Lidocaine's unique properties, including nonlinear pharmacokinetics, have limited its modern-day use. Objective The purpose of this review is to offer a better understanding of the properties of this unique treatment, which we hope will allow more practitioners to offer this to their patients. Methods An analysis of the history, pharmacokinetics, and relevant uses of lidocaine in headache medicine based on a synthesis of the medical literature and clinical experience. Results Lidocaine is an amide anesthetic that inhibits voltage gated sodium channels, and lidocaine metabolism occurs exclusively in the liver. One lidocaine metabolite has its own unique properties and may be an active form of the drug. Conclusion Open label and retrospective studies have investigated the use of lidocaine in many headache disorders, primarily via injection or infusion. Further research into the active metabolite of lidocaine may allow for its use as a novel nonopiate treatment of chronic pain.
Propeller wake evolution mechanisms in oblique flow conditions

In the present study the wake flow past an isolated propeller operating in oblique flow conditions is investigated experimentally. In particular, the investigation concerns a systematic topological comparison of the wake behaviour in axisymmetric and in oblique inflow conditions, for three inclination angles, and is focused on an analysis of the underlying mechanisms of wake evolution and instability. To this end, the experiment has been designed to investigate the dynamics of propeller vortical structures over a wide spatial extent covering the wake region from the propeller disk up to 4.5 diameters in the streamwise direction. Detailed flow measurements have been undertaken by particle image velocimetry (PIV), using a multicamera configuration with three cameras arranged side by side. This allowed simultaneous acquisition of a large flow extent at a spatial resolution adequate to resolve the smallest vortical structures involved in the process of propeller wake instability. The analysis has been based on both phase-locked averaged and instantaneous flow fields. The study extends the knowledge on the subject of propeller wake dynamics, highlighting the major hydrodynamic effects that non-axisymmetric propeller operating conditions exert on the mechanisms of wake evolution, instability and breakdown, such as asymmetric destabilization of the tip vortices on the leeward and windward sides of the wake, and the interference between the tip and the junction vortices, as well as the cause–effect relation between the breakdown of the blade trailing wake and the instability of the tip and hub vortices.
Yield of downstream tests after exercise treadmill testing: a prospective cohort study

Objectives The purpose of this study was to estimate the frequency and results of downstream testing after exercise treadmill tests (ETTs). Background The utility of additional diagnostic testing after ETT is not well characterized. Methods We followed consecutive individuals without known coronary artery disease referred for clinical ETT at a large medical center. We measured the frequency and results of downstream imaging tests and invasive angiography within 6 months of ETT and the combined endpoint of survival free from cardiovascular death, myocardial infarction, and coronary revascularization. Results Among 3,656 consecutive subjects who were followed for a mean of 2.5 ± 1.1 years, 332 (9.0%) underwent noninvasive imaging and 84 (2.3%) were referred directly to invasive angiography after ETT. The combined endpoint occurred in 76 (2.2%) patients. The annual incidence of the combined endpoint after negative, inconclusive, and positive ETT was 0.2%, 1.3%, and 12.4%, respectively (p Conclusions Among patients referred for additional testing after ETT, the lowest yield was observed among individuals with rapid recovery of ECG changes or negative ETT, whereas the highest yield was observed among those with typical angina despite negative ECG or a positive ETT. These findings may be used to identify patients who are most and least likely to benefit from additional testing.
Prevenzione delle complicanze in chirurgia mininvasiva

Questo capitolo ha lo scopo di sensibilizzare riguardo le complicanze che possono verificarsi nella chirurgia mininvasiva. Esso si propone di aiutarvi a evitare le potenziali difficolta.
8 – ADOLESCENT SEXUALITY

Publisher Summary This chapter discusses sexual experiences of adolescents. Several commentators on the current social scene have described the trend toward liberalized sexual norms as a sexual revolution. Nudity and sex in the movies are much more widely accepted. People are discussing sexual lifestyles much more openly than in the recent past. Sexually explicit language is present in literature and in the media in a way that was neither legally nor socially acceptable just a few years ago. A shift in attitudes toward sexual behavior is just one of the elements of a sexual revolution. A second element is an increase in sexual participation, reflected in the incidence of premarital intercourse. A third element is earlier participation in sexual activities; younger adolescents who participate in advanced forms of sexual behavior would demonstrate this aspect of a sexual revolution. A fourth element of liberalization concerns changes in patterns of sexual behavior, including willingness to engage in more exotic forms of sexual expression, such as oral–genital contact, sodomy, and group sex. In the area of sexuality, adolescents tend to adopt the standards and behavior that they think characterize their reference group. Among college students, peer group influences on sexual behavior and standards increases during the college years.
Das Prinzip der maximalen Entropie

In den vorangehenden Kapiteln haben wir den Gebrauch der Bayes’schen Gleichung zur Modifikation einer gegebenen Wahrscheinlichkeitsverteilung betrachtet. Wenn die Anfangswahrscheinlichkeiten gleich p(A i lX) sind und neue Daten D verfugbar werden, so sind die Wahrscheinlichkeiten gemas $$p(A_i |DX) = \frac{{p(A_i |X)\;p(D|A_i X)}} {{\mathop {\sum p(A_i |X)\;p(D|A_i X)}\limits_i }}$$ (5.1) zu korrigieren, wobei der Nenner gemas Gleichung (3.3) erweitert wurde.
Avoiding the climate failsafe point.

Thomas E. Lovejoy Lee Hannah Although models of climate and vegetation change are greatly improving, they remain far from perfect. For example, on the one hand, recent modeling studies indicate that limiting temperature increase to 1.5°C will greatly reduce the impact on the ranges of insect, vertebrate, and plant communities. However, we also know that, since these models do not account for critical climate-sensitive relationships among species, their predictions are serious underestimates. New research is allowing scientists to better understand the fine-tunings of climate-sensitive relationships among species, including how even very small changes of temperature can have devastating effects on ecosystems. We know, for example, that many coral bleaching events are due to temperature-based disruption of coral reef ecosystems. Even a subtle increase of temperature for a short period can cause coral animals to eject their symbiotic algae, a separation that quickly leads to coral bleaching and often to mortality and the collapse of the entire reef ecosystem. Another example of huge impacts resulting from small temperature changes is that slightly …
Lithium niobate-based transparent ultrasound transducers for photoacoustic imaging

This Letter demonstrates lithium niobate (LiNbO3)-based transparent ultrasound transducers (TUTs) for photoacoustic imaging applications. The TUTs were fabricated by coating the top and bottom surfaces of a 0.25 mm thick LiNbO3wafer with transparent indium-tin-oxide (ITO) electrodes. The resulting transducers showed ∼80% optical transparency in the wavelength range of 690–970 nm. The TUTs had a resonant frequency of 14.5 MHz and ∼70% photoacoustic bandwidth. The versatility of the TUT approach is demonstrated by introducing two different transparent photoacoustic imaging (PAI) geometries. In one method, which suits endoscopy applications, an optical fiber of a laser diode is directly fixed on the backside of a 2.5 mm diameter TUT, and the fiber-TUT device is raster scanned to form 3D photoacoustic images. In the second method, which suits high-throughput applications, a free-space optical-only raster scanning of the laser fiber across a 1 cm×1 cm planar TUT yielded 3D photoacoustic images. The proposed TUT approach is low in cost, easy to manufacture, compatible with conventional clinical ultrasound electronics, and scalable for different configurations, including 2D TUT arrays to achieve real-time 3D high-throughput PAI.
VENTRICULAR ARRHYTHMIAS MOST LIKELY TO OCCUR IN THE IMMEDIATE POST-DIALYSIS PERIOD IN PATIENTS WITH END-STAGE RENAL DISEASE AND CARDIAC IMPLANTABLE ELECTRONIC DEVICES

Temporal relationships exist between arrhythmia burden, sudden cardiac death (SCD), and hemodialysis (HD) schedule, which is divided into two short interdialytic periods (SIDP, 48 hr), and one long interdialytic period (LIDP, 72 hr). The LIDP is associated with increased arrhythmia risk. We
Associations between trying to control weight, weight control behaviors and current electronic cigarette usage in middle and high school students: A cross-sectional study in Zhejiang Province, China.

Introduction Previous research has indicated that weight control behaviors are linked to cigarette smoking, whether these relationships extend to electronic cigarettes (e-cigarettes) is unknown. This study aims to examine the association between weight control behaviors and current e-cigarette usage among middle and high school students in China. Methods Based on the 2017 Zhejiang Youth Risk Behavior Survey, 17359 students were included and relevant data involving e-cigarette and weight control behaviors were collected via self-reported questionnaires. Logistic regression models were used to examine the associations between trying to control weight, specific weight control behaviors and current e-cigarette usage. Odds ratios (ORs) and their 95% confidence intervals (CIs) are reported. Results Of the 17359 students, 374 (2.15%) were current e-cigarette users. No significant association was observed between trying to control weight and current e-cigarette usage (OR=1.01; 95% CI: 0.81-1.28). Significant associations were found between current e-cigarette usage and unhealthy weight control behaviors of eating less food, fewer calories (OR=1.74; 95% CI: 1.33-2.27), as well as taking laxatives (OR=3.34; 95% CI: 2.11-5.27), taking diet pills (OR=2.63; 95% CI: 1.72-4.02) and going without eating for 24 hours or more (OR=2.74; 95% CI: 1.86-4.04). Conclusions A positive association was found between unhealthy weight control behaviors and current e-cigarette usage in adolescents. Specific education programs on unhealthy weight control behaviors should be considered in adolescents.
Using human pluripotent stem cell models to study autism in the era of big data

Advances in human pluripotent stem cell (hPSC) biology coupled with protocols to generate diverse brain cell types in vitro have provided neuroscientists with opportunities to dissect basic and disease mechanisms in increasingly relevant cellular substrates. At the same time, large data collections and analyses have facilitated unprecedented insights into autism genetics, normal human genetic variation, and the molecular landscape of the developing human brain. While such insights have enabled the investigation of key mechanistic questions in autism, they also highlight important limitations associated with the use of existing hPSC models. In this review, we discuss four such issues which influence the efficacy of hPSC models for studying autism, including (i) sources of variance, (ii) scale and format of study design, (iii) divergence from the human brain in vivo, and (iv) regulatory policies and compliance governing the use of hPSCs. Moreover, we advocate for a set of immediate and long-term priorities to address these issues and to accelerate the generation and reproducibility of data in order to facilitate future fundamental as well as therapeutic discoveries.
Rationale and methods of the Advanced R2Eperfusion STrategies for Refractory Cardiac Arrest (ARREST) trial.

Background Venoarterial extracorporeal membrane oxygenation has emerged as a prominent therapy for patients with refractory cardiac arrest. However, the optimal time of initiation remains unknown. Aim The aim was to assess the rate of survival to hospital discharge in adult patients with refractory ventricular fibrillation/pulseless ventricular tachycardia out-of-hospital cardiac arrest treated with 1 of 2 local standards of care: (1) early venoarterial extracorporeal membrane oxygenation–facilitated resuscitation for circulatory support and percutaneous coronary intervention, when needed, or (2) standard advanced cardiac life support resuscitation. Design Phase II, single-center, partially blinded, prospective, intention-to-treat, safety and efficacy clinical trial. Population Adults (aged 18–75), initial out-of-hospital cardiac arrest rhythm of ventricular fibrillation/pulseless ventricular tachycardia, no ROSC following 3 shocks, body morphology to accommodate a Lund University Cardiac Arrest System automated cardiopulmonary resuscitation device, and transfer time of Setting Hospital-based. Outcomes Primary: survival to hospital discharge. Secondary: safety, survival, and functional assessment at hospital discharge and 3 and 6 months, and cost. Sample size Assuming success rates of 12% versus 37% in the 2 arms and 90% power, a type 1 error rate of .05, and a 15% rate of withdrawal prior to hospital discharge, the required sample size is N = 174 evaluated patients. Conclusions The ARREST trial will generate safety/effectiveness data and comparative costs associated with extracorporeal cardiopulmonary resuscitation, informing broader implementation and a definitive Phase III clinical trial.
Cultivating Musical Talent.

The issue of parenting children and adolescents who demonstrate an aptitude or potential for music has not been extensively investigated or written about. The purpose of this paper is to explore so...
Examining Students' Confidence to Learn Online, Self-Regulation Skills and Perceptions of Satisfaction and Usefulness of Online Classes.

As online class offerings continue to proliferate and more students take at least one online class in college, more research is needed to explore factors that impact students’ perceptions of their online classes. Past research has found a positive relationship between students’ computer self-efficacy and their satisfaction with online learning, but little research has explored how learning management system and online learning self-efficacy relate to perceptions of satisfaction and perceived usefulness of online classes. In addition to confidence, students must also implement and apply their learning skills in an online environment; thus self-regulation and time management as well as past online learning experience are additional factors that have been shown to be related to satisfaction with and usefulness of online learning. This study explores how students’ confidence regarding their ability to use online learning platforms, utilize self-regulation strategies, and their confidence in their ability to learn in online classes predict both their satisfaction with and perceived usefulness of online classes. Multiple regression analyses revealed that students’ confidence to learn online was the strongest positive predictor of satisfaction and usefulness of online classes. The results indicate that exploring students’ purpose and reasons for taking online classes, beyond a students’ skill set and learning strategies, are fruitful directions to pursue when assessing evaluations of online classes.
Standards and Export Decisions: Firm-Level Evidence from Developing Countries

Standards and technical regulations set in importing countries have become a rising concern to exporters, especially to those in developing countries. This paper examines the importance of various types of standards in developing-country firms' export decisions. Drawn from the World Bank Technical Barriers to Trade (TBT) Survey database, we find that different types of standards exhibit sharply distinct relations with firms' intensive and extensive margins of exports. Quality standards are positively correlated not only with firms' average export volume across markets and products but also their export scope, measured by the number of export markets and products. A similar relationship is found between labeling requirements and export scope. Certification procedures, however, are associated with a significant decline in the number of export markets and export products. Our results suggest that different approaches should be taken to address each type of technical regulations. Not all standards need to be negotiated away to boost trade, but negotiations on certification procedures with the aim of reaching Mutual Recognition Agreements (MRAs) can help firms improve economies of scale and scope.
Transcriptional profiling of two contrasting genotypes uncovers molecular mechanisms underlying salt tolerance in alfalfa

Alfalfa is an important forage crop that is moderately tolerant to salinity; however, little is known about its salt-tolerance mechanisms. We studied root and leaf transcriptomes of a salt-tolerant (G03) and a salt-sensitive (G09) genotype, irrigated with waters of low and high salinities. RNA sequencing led to 1.73 billion high-quality reads that were assembled into 418,480 unigenes; 35% of which were assigned to 57 Gene Ontology annotations. The unigenes were assigned to pathway databases for understanding high-level functions. The comparison of two genotypes suggested that the low salt tolerance index for transpiration rate and stomatal conductance of G03 compared to G09 may be due to its reduced salt uptake under salinity. The differences in shoot biomass between the salt-tolerant and salt-sensitive lines were explained by their differential expressions of genes regulating shoot number. Differentially expressed genes involved in hormone-, calcium-, and redox-signaling, showed treatment- and genotype-specific differences and led to the identification of various candidate genes involved in salinity stress, which can be investigated further to improve salinity tolerance in alfalfa. Validation of RNA-seq results using qRT-PCR displayed a high level of consistency between the two experiments. This study provides valuable insight into the molecular mechanisms regulating salt tolerance in alfalfa.
Obstetric Inpatient and Ultrasound Clinical Personnel Absences during the COVID-19 Pandemic in New York City.

Objective To review obstetric personnel absences at a hospital during the initial peak of coronavirus disease 2019 (COVID-19) infection risk in New York City from March 25 to April 21, 2020. Study Design This retrospective study evaluated absences at Morgan Stanley Children's Hospital. Clinical absences for (1) Columbia University ultrasonographers, (2) inpatient nurses, (3) labor and delivery operating room (OR) technicians, (4) inpatient obstetric nurse assistants, and (5) attending physicians providing inpatient obstetric services were analyzed. Causes of absences were analyzed and classified as illness, vacation and holidays, leave, and other causes. Categorical variables were compared with the chi-square test or Fisher's exact test. Results For nurses, absences accounted for 1,052 nursing workdays in 2020 (17.2% of all workdays) compared with 670 (11.1%) workdays in 2019 (p Conclusion COVID-19 outbreak surge planning represents a major operational issue for medical specialties such as critical care due to increased clinical volume. Findings from this analysis suggest it is prudent to devise backup staffing plans. Key Points
Family Structure and Children’s Economic Well-Being: Incorporating Same-Sex Cohabiting Mother Families

Research on family structure and child well-being rarely includes children in same-sex parent families, a notable omission since 28 % of female–female couple households contain children. Using the 2010–2013 pooled current population survey (CPS), we examined children’s economic well-being by family structure. These data were ideal for this study because they included a sizeable number of children in same-sex cohabiting mother families and the CPS measured both official and supplemental poverty, incorporating the cohabiting partner. Using the official poverty measure, children in same-sex cohabiting mother families were more likely to be poor than their counterparts in either different-sex cohabiting or married parent families. Using the supplemental poverty measure, children in same-sex mother families were no more likely to be poor than children in all other types of different-sex two-parent families.
A Tale of Two Realisms: Expanding the Institutions Debate

Recent developments in the study of international institutions have created a need and opportunity for restating the traditional realist view of the role of institutions in international relations. Advancing what he claimed was realism’s perspective on this issue, John Mearsheimer (1994/95) forcefully staked out an extreme position that institutions are essentially epiphenomenal. Mearsheimer’s arguments, however, derived from Waltzian neorealism, are inconsistent with traditional realism’s concern for the origins and influence of international institutions. Moreover, they do not reflect the views of the newest wave of modified structural realists who adopt many of the insights of neoliberal institutionalism. In an attempt to show that pre-Waltzian realists had much to say about institutions, this essay reviews the neorealist/neoliberal debate over institutions, clarifies the basic differences between traditional realism and neorealism, and resurfaces traditional realist arguments concerning the effects of state power and interests on international institutions and global order. Combining insights from both traditional realism and neorealism, a model is constructed that considers how the characteristics of states, their interactions, and the structure of the international system facilitate understanding the ways in which power will be exercised, the type of global order that will be produced, and the level of global institutionalization that can be expected.
Relações Brasil - Canada: potenciais de uma relação bilateral mais efetiva

In recent years Brazil and Canada have to adapt to the changes in the international system. Its international insertion strategies have changed since the fall of the bipolar system. The two countries maintain active foreign policies and interests. Recently opted to develop a strategic partnership. The aim of this paper is to discuss in acomparative way Brazilian and Canadian foreign policies, focusing on the reconfiguration of the international order since the end of the Cold War, observing the convergence and divergence of interests.
The Hidden Dress Code Dilemma

(1986). The Hidden Dress Code Dilemma. The Clearing House: A Journal of Educational Strategies, Issues and Ideas: Vol. 59, No. 6, pp. 277-279.
The subunit interface of the Escherichia coli ribosome. Crosslinking of 30 S protein S9 to proteins of the 50 S subunit.

Abstract Purified 50 S ribosomal subunits were found to contain significant amounts of protein coincident with the 30 S proteins S9 and/or S11 on two-dimensional polyacrylamide/urea electropherographs. Peptide mapping established that the protein was largely S9 with smaller amounts of S11. Proteins S5 and L6 were nearly coincident on the two-dimensional polyacrylamide/urea electropherographs. Peptide maps of material from the L6 spot obtained from purified 50 S subunits showed the presence of significant amounts of the peptides corresponding to S5. Experiments in which 35S-labelled 30 S subunits and non-radioactive 50 S subunits were reassociated to form 70 S ribosomes showed that some radioactive 30 S protein was transferred to the 50 S subunit. Most of the transferred radioactivity was associated with two proteins, S9 and S5. Sulfhydryl groups were added to the 50 S subunit by amidination with 2-iminothiolane (methyl 4-mercaptobutyrimidate). These were oxidized to form disulfide linkages, some of which crosslinked different proteins of the intact 50 S ribosomal subunit. Protein dimers were partially fractionated by sequential salt extraction and then by electrophoresis of each fraction in polyacrylamide gels containing urea. Slices of the gel were analysed by two-dimensional polyacrylamide/sodium dodecyl sulfate diagonal gel electrophoresis. Final identification of the constituent proteins in each dimer by two-dimensional polyacrylamide/urea gel electrophoresis showed that 50 S proteins L5 and L27 were crosslinked to S9. The evidence suggests that proteins S5, S9, S11, L5 and L27 are located at the interface region of the 70 S ribosome.
Estimating Effects of an Urban Growth Boundary on Land Development

This study estimates the effects of an urban growth boundary (UGB) on land development decisions in Knox County, TN, using a heteroscedastic probit model. With combined effects of increased land development within the city boundary and decreased development within the UGB and the neighboring town of Farragut after the implementation of UGB, the UGB of Knox County has been successful in urban revitalization within the city boundary and discouraging urban sprawl. These UGB impacts may be related to the city government having the right to annex land parcels within the UGB without consent of land owners.
Applying valiant's learning framework to Al concept-learning problems

Abstract We present an overview of some recent theoretical results in the learning framework introduced by Valiant in [Valiant, 1984] and further developed in [Valiant 1985; Blumer, et al., 1987; 1989; Pitt and Valiant, 1988; Haussler, 1988; Angluin and Laird, 1988; Angluin, 1988; Rivest, 1987; Haussler, 1989; Kearns, et al., 1987a; 1987b]. Our focus is on applications to AI problems of learning from examples as given in [Haussler, 1988; 1989] and [Kearns, et al., 1987a; 1987b], along with a comparison to the work of Mitchell on version spaces [Mitchell, 1982]. We discuss learning problems for both attribute-based and structural domains. This is a revised and expanded version of [Haussler, 1987].
Accelerating parallel analysis of scientific simulation data via Zazen

As a new generation of parallel supercomputers enables researchers to conduct scientific simulations of unprecedented scale and resolution, terabyte-scale simulation output has become increasingly commonplace. Analysis of such massive data sets is typically I/O-bound: many parallel analysis programs spend most of their execution time reading data from disk rather than performing useful computation. To overcome this I/O bottleneck, we have developed a new data access method. Our main idea is to cache a copy of simulation output files on the local disks of an analysis cluster's compute nodes, and to use a novel task-assignment protocol to co-locate data access with computation. We have implemented our methodology in a parallel disk cache system called Zazen. By avoiding the overhead associated with querying metadata servers and by reading data in parallel from local disks, Zazen is able to deliver a sustained read bandwidth of over 20 gigabytes per second on a commodity Linux cluster with 100 nodes, approaching the optimal aggregated I/O bandwidth attainable on these nodes. Compared with conventional NFS, PVFS2, and Hadoop/HDFS, respectively, Zazen is 75, 18, and 6 times faster for accessing large (1-GB) files, and 25, 13, and 85 times faster for accessing small (2-MB) files. We have deployed Zazen in conjunction with Anton--a special-purpose supercomputer that dramatically accelerates molecular dynamics (MD) simulations-- and have been able to accelerate the parallel analysis of terabyte-scale MD trajectories by about an order of magnitude.
Dietary Fat Intake and Carotid Artery Wall Thickness: The Atherosclerosis Risk in Communities (ARIC) Study

Associations between atherosclerosis and dietary fat and cholesterol have been demonstrated in numerous animal experiments. The relation between these dietary components and atherosclerosis has not previously been reported in a population-based study among human beings. The associations of dietary fat and cholesterol with carotid artery wall thickness (atherosclerosis) were investigated in a population-based study, the Atherosclerosis Risk in Communities (ARIC) Study, from 1987 to 1989. Participants were 2,095 black women, 5,146 white women, 1,318 black men and 4,589 white men, aged 45-64 years, recruited from four US communities: Jackson, Mississippi; Forsyth County, North Carolina; Washington County, Maryland; and Minneapolis, Minnesota. Habitual diet was assessed with a food frequency questionnaire. Wall thickness was measured with B-mode ultrasound. After adjustment for age and energy intake, animal fat, saturated fat, monounsaturated fat, cholesterol, and Keys' score were positively related to wall thickness, while vegetable fat and polyunsaturated fat were inversely related to wall thickness. These associations persisted after further adjustment for smoking and hypertension and were consistent across the four race and sex groups. Thus, elements of habitual dietary intake were consistently associated with carotid artery wall thickness, compatible with their putatively atherogenic and antiatherogenic properties.
THE RELATIVE CONTRIBUTIONS OF DISPERSION AND SOLUTION STRENGTHENING IN Zr- Sn-Nb ALLOYS

Dispersion strengthening by Zr/sub 4/Sn in a matrix of constant composition in the Zr--Nb- Sn system was considerably greater than solution strengthening by either niobium or tin. Niobium was more effective than tin in solution hardening, although, the results could not be analyzed by any of the existing theories of solution strengthening. The best agreement of the dispersion strengthening data was obtained with the Gensamer hypothesis, which predicts a linear relationship between yield stress and the negative logarithm of the interparticle spacing. Fair agreement was also achieved with the Lenel- Ansell theory, although it was shown that the agreement was fortuitous. It was concluded that a combination of both solution and dispersion strengthening can result in considerable improvement in zirconium alloys and can provide a basis of strengthening weak, corrosion resistant alloys. (auth)
Autologous iliac crest bone graft: Should it still be the gold standard for treating nonunions?

Nonunion is a common complication following long-bone fracture, with a prevalence that ranges from 2.5-46%, depending on the location and severity of the injury to the bone, soft tissue, and vascular structures. The treatment of nonunions involves addressing the biology of fracture repair and the mechanical stability of fracture fixation, which are interrelated. Nonunion treatment has traditionally included the addition of autograft from the iliac crest to enhance healing. However, there an associated morbidity with the harvesting of the graft, and alternatives such as bone marrow aspirate, platelet-rich plasma, allograft, and ceramics have also been studied. In addition, new advances in the understanding of the cellular and molecular mechanisms of fracture repair have led to the use of growth factors, such as bone morphogenetic proteins, to accelerate bone healing. This article reviews the benefits of iliac crest bone graft relative to those of other modalities in the treatment of nonunions.
The Review of Political Economy at 25: Past, Present and Future

I met John Pheby in the summer 1986, at an international conference held in Toronto. I was participating in a session on Post Keynesian economics with John Smithin and Ingrid Rima. At the time, I w...
Brain tumor imaging: posttherapy.

I would like to thank Mauricio Castillo, Editor-in-Chief of the American Journal of Neuroradiology ( AJNR ), for inviting me to be Guest Editor for the AJNR Special Collection titled Brain Tumor Imaging, Volume 1: Pretherapy . Begun in 2008, the biannual Special Collection is a compilation of
Two years of appropriateness criteria for echocardiography: what have we learned and what else do we need to do?

As noninvasive cardiovascular imaging has become more sophisticated and accessible, its use has increased steadily. In the United States, according to Medicare data, transthoracic echocardiography (TTE) constitutes a significant proportion of cardiovascular imaging. This modality is used in a variety of clinical settings and provides a great deal of information at virtually no risk to patients. Because TTE is seen as benign and is widely available, the potential for overuse exists. By developing echocardiographic appropriateness criteria (AC), the American College of Cardiology Foundation and the American Society of Echocardiography have provided a framework of broad indications that encompasses many clinical scenarios. The goals of the AC are to provide a rational approach to the use of cardiovascular imaging and to improve patient care and health outcomes in a cost-effective manner. Ideally, AC should help providers moderate their own practice patterns without stifling clinical judgment, reducing if not supplanting the need for external regulation by insurers and other third parties. These are particularly important goals given the current dialogue on health care reform, as it appears that there are many parties that wish to control how imaging is utilized in an effort to reduce costs. AC are different from clinical guidelines. Clinical guidelines describe a comprehensive list of the conditions for which a test is indicated. AC include more selective indications than guidelines, typically those that are most commonly encountered (because these have the largest potential to generate inappropriate studies). Many clinicians might consider a test to be appropriate if it provides important new information and inappropriate if it does not provide any new information. However, in the AC, an appropriate test is defined as ‘‘one in which the expected incremental information, combined with clinical judgment, exceeds the expected negative consequences by a sufficiently wide margin for a specific indication that the procedure is generally considered acceptable.’’ This means that the AC may categorize some tests as ‘‘appropriate’’ even though the results simply confirm what is already known, while other tests may be categorized as ‘‘inappropriate’’ even though they do in fact provide new information that might be valuable for patient care. Also, there will be scenarios in which it is uncertain or unclear if a test is appropriate. Because the AC are not all inclusive, some tests will not fit into one of the covered scenarios and thus will be ‘‘unclassifiable.’’ The AC for TTE and transesophageal echocardiography (TEE) were published in July 2007, and those for stress echocardiography ap-
Near Infrared Reflectance Spectroscopic Analysis of Sodium Chlorite-Treated Forages and Other Plant Materials

Abstract The ability of near infrared reflectance spectroscopy to measure the fiber content and in vitro rumen digestibility of feedstuffs treated with sodium chlorite was determined. Six hays (alfalfa, tall fescue, orchardgrass, red clover, timothy, and a grass-legume hay), two straws (barley and wheat), four stovers (two corn and two soybean), three hulls (peanut, rice, and soybean), and corn cobs were treated with sodium chlorite at 11 concentrations to give .000 to .394g of sodium chlorite per g of feed (dried at 60°C). Analysis results for the treated feeds using every third sample as a validation set gave standard errors of analysis and r 2 as follows for the validation set: protein .6, .99; neutral detergent fiber 3.2, .95; acid detergent fiber 2.2, .95; lignin 1.5, .92; hemicellulose 3.1, .91; total carbohydrate 3.4, .94; cellulose 1.9, .94; digestible ADF 6.8, .92; digestible NDF 5.8, .95; and total digestible organic matter 4.0 and .96. These values were similar to those generated for a second set of untreated feeds (67 samples of 5 feeds), showing that treatment did not reduce the validity of using near infrared reflectance spectroscopy to predict feed quality. Studies involving various calibration sets showed that satisfactory results could be obtained using as few as 3/16 of the treated feeds as the calibration set.
Interaction, Nonlinearity, and Multicollinearity: implications for Multiple Regression:

Moderated Hierarchical Multiple Regression (MHMR) is typically used to test for the presence of interactions. When an interaction term is composed of correlated variables, linearity and additivity become confounded. The result of this confounding is that an interaction term in MHMR may be statistically significant only because of its overlap with unmeasured nonlinear terms. I recommend that squared terms be used as covariates in such situations and show that the resulting loss of power with respect to the test of significance for the interaction term is limited to that associated with the loss of degrees of freedom and is therefore negligible if it exists at all.
Site-directed spin labeling and chemical crosslinking demonstrate that helix V is close to helices VII and VIII in the lactose permease of Escherichia coli

Site-directed chemical cleavage of lactose permease indicates that helix V is in close proximity to helices VII and VIII. To test this conclusion further, permease containing a biotin-acceptor domain and paired Cys residues at positions 148 (helix V) and 228 (helix VII), 148 and 226 (helix VII), or 148 and 275 (helix VIII) was affinity purified and labeled with a sulfhydryl-specific nitroxide spin label. Spin-spin interactions are observed with the 148/228 and 148/275 pairs, indicating close proximity between appropriate faces of helix V and helices VII and VIII. Little or no interaction is evident with the 148/226 pair, in all likelihood because position 226 is on the opposite face of helix VII from position 228. Broadening of the electron paramagnetic resonance spectra in the frozen state was used to estimate distance between the 148/228 and the 148/275 pairs. The nitroxides at positions 148 and 228 or 148 and 275 are within approximately 13-15 A. Finally, Cys residues at positions 148 and 228 are crosslinked by dibromobimane, a bifunctional crosslinker that is approximately 5 A. long, while no crosslinking is detected between Cys residues at positions 148 and 275 or 148 and 226. The results provide strong support for a structure in which helix V is in close proximity to both helices VII and VIII and is oriented in such a fashion that Cys-148 is closer to helix VII.
Quantitative structure‐activity relationships for toxicity of phenols using regression analysis and computational neural networks

Quantitative structure-toxicity models were developed that directly link the molecular structures of a set of 50 alkylated and/or halogenated phenols with their polar narcosis toxicity, expressed as the negative logarithm of the IGC50 (50% growth inhibitory concentration) value in millimoles per liter. Regression analysis and fully connected, feed-forward neural networks were used to develop the models. Two neural network training algorithms (back-propagation and a quasi-Newton method) were employed. The best model was a quasi-Newton neural network that had a root-mean-square error of 0.070 log units for the 45 training set phenols and 0.069 log units for the five cross-validation set phenols.
Aicardi‐Goutières Syndrome: Cutaneous, Laboratory, and Radiologic Findings: A Case Report

Abstract: Aicardi-Goutieres syndrome is a primarily autosomal recessive disorder characterized by congenital encephalopathy, basal ganglia calcifications, elevated interferon-α in blood and cerebral spinal fluid, and negative studies for intrauterine infections that can mimic the syndrome. Cutaneous manifestations include pernio, photosensitivity, and cutaneous vasculitis. We present a case of Aicardi-Goutieres syndrome to increase awareness of the disorder and its possible relation to systemic lupus erythematosus.
Determination of densities and heat capacities from speed of sound measurements for 1,1,1,2-tetrafluoroethane

Abstract The speed of sound u is both formally independent of the amount of substance and can be measured easily with high precision (typically Δ u / u − 5 ). Measurement of this quantity offers a favorable route for obtaining density ρ , molar isochoric heat capacity C V , m , and molar isobaric heat capacity C p , m values. This transformation from u to other thermodynamic properties, involves the solution of a second-order differential equation on either isobars, or isochores. In this paper, we compare both equation sets for 1,1,1,2-tetrafluoroethane (HFC-134a) which is a slightly polar fluid. In the absence of reliable experimental speed of sound data over the whole fluid surface, an accurate Helmholtz function equation of state for HFC-134a was used to simulate property data for this study. These data were generated at reduced temperatures T r = T / T c between T r = 0.75 and T r = 1.25 and at reduced pressures p r = p / p c up to p r = 6. The isochoric equation set was found to be more stable. For data and initial conditions without errors, the fractional uncertainties in ρ and C V , m were 0.002 and 0.02, respectively. Sensitivity studies were conducted on the isochoric equation set to document effects of interpolation step size, accuracy of initial conditions, and presence of random errors in the data. When all sources of error are included, the uncertainties in density and isochoric heat capacity were no worse than any of the individual sensitivity studies.
Kinetics of radiation-induced precipitation at the alloy surface

Abstract Radiation-induced precipitation of a new phase at the surface of an alloy during irradiation at elevated temperatures was studied with the aid of a kinetic model of segregation. The preferential coupling of solute atoms with the defect fluxes gives rise to a strong solute enrichment at the surface, which, if surpassing the solute solubility limit, leads to the formation of a precipitate layer. The moving precipitate/matrix interface was accommodated by means of a mathematical scheme that transforms spatial coordinates into a reference frame in which the boundaries are immobile. Sample calculations were performed for precipitation of the γ'-Ni 3 Si layer on Ni-Si alloys undergoing electron irradiation. The dependences of the precipitation kinetics on the defect-production rate, irradiation temperature, internal defect sink concentration and alloy composition were investigated systematically.
Prevalence of Cytomegalovirus Antibody in Subjects Between the Ages of 6 and 22 Years

We determined the prevalence of antibody to cytomegalovirus (CMV) in three groups between 1985 and 1987. Group I consisted of 511 subjects 6-22 y old, group II consisted of 920 subjects 18-21 y old, and group III of 113 subjects 18-22 y old. The overall prevalence of antibody in these three groups was 34%, 24%, and 28%, respectively. Prevalence of antibody in white subjects (24%, 21%, and 24%, respectively) was significantly lower than that in nonwhite subjects. In group I, there was no increase in prevalence with age in white subjects, but the percentage of individuals with antibody increased with age among nonwhite subjects. It is of obvious concern that a large proportion of white women entering childbearing years lack CMV antibody.