cssi/SciSciGPT-SciSciNet huggingface dataset:
Are at least 12 months of dual antiplatelet therapy needed for all patients with drug-eluting stents? Not all patients with drug-eluting stents need at least 12 months of dual antiplatelet therapy.

> “Things are not always as simple as they first appear.” > > Phaedrus, 25 ad 1 The optimal duration of dual antiplatelet therapy (DAPT) after coronary arterial stenting is an important question for clinicians and patients alike and represents a dynamic state of benefit and risk to achieve optimal outcomes. Clinicians must carefully balance the risk for future coronary artery–related events with an assessment of bleeding risk and, in many instances, recognize a changing risk-benefit relationship from the time of stent implantation. Patients must work closely with their healthcare providers to understand their medical condition—the basis for and importance of the treatments recommended—and to openly share their values, preferences, and anticipated obstacles to adhering to medical advice, including cost and limited access to ambulatory clinics in the community. The debate over duration of therapy comes at a time when national health care is facing serious challenges, with costs to individual patients contributing to an increasing divide among social classes in the United States and abroad.2 It also presents an opportunity to honor a pragmatic side of precision medicine as a priority for population health and the scientific community.3 Response by Brener on p 2019 To arrive at our position that not all patients undergoing coronary arterial stent implantation require at least 12 months of DAPT, we posed the following questions: What is the goal of DAPT following stent implantation; what is the evidence in favor of either 12 months of DAPT after stent implantation; what are the underlying determinants of benefit and risk for DAPT; what are the most common factors that affect the duration of DAPT in clinical practice; and who are the optimal candidates for <12 months of DAPT? As with other blood-contacting medical devices, thrombosis is the predominant cause of failure after stent implantation. Accordingly, …
Sequence, Structure and Network Methods to Uncover Cancer Genes

A major aim of cancer genomics is to pinpoint which somatically mutated genes are involved in tumor initiation and progression. This is a difficult task, as numerous somatic mutations are typically observed in each cancer genome, only a subset of which are cancer-relevant, and very few genes are found to be somatically mutated across large numbers of individuals. In this talk, I will overview three methods my group has introduced for identifying cancer genes. First, I will present a framework for uncovering cancer genes, differential mutation analysis, that compares the mutational profiles of genes across cancer genomes with their natural germline variation across healthy individuals. Next, I will show how to leverage per-individual mutational profiles within the context of protein-protein interaction networks in order to identify small connected subnetworks of genes that, while not individually frequently mutated, comprise pathways that are altered across (i.e., "cover") a large fraction of individuals. Finally, I will demonstrate that cancer genes can be discovered by identifying genes whose interaction interfaces are enriched in somatic mutations. Overall, these methods recapitulate known cancer driver genes, and discover novel, and sometimes rarely-mutated, genes with likely roles in cancer.
Regulation of myelin structure and conduction velocity by perinodal astrocytes

The speed of impulse transmission is critical for optimal neural circuit function, but it is unclear how the appropriate conduction velocity is established in individual axons. The velocity of impulse transmission is influenced by the thickness of the myelin sheath and the morphology of electrogenic nodes of Ranvier along axons. Here we show that myelin thickness and nodal gap length are reversibly altered by astrocytes, glial cells that contact nodes of Ranvier. Thrombin-dependent proteolysis of a cell adhesion molecule that attaches myelin to the axon (neurofascin 155) is inhibited by vesicular release of thrombin protease inhibitors from perinodal astrocytes. Transgenic mice expressing a dominant-negative fragment of VAMP2 in astrocytes, to reduce exocytosis by 50%, exhibited detachment of adjacent paranodal loops of myelin from the axon, increased nodal gap length, and thinning of the myelin sheath in the optic nerve. These morphological changes alter the passive cable properties of axons to reduce conduction velocity and spike-time arrival in the CNS in parallel with a decrease in visual acuity. All effects were reversed by the thrombin inhibitor Fondaparinux. Similar results were obtained by viral transfection of tetanus toxin into astrocytes of rat corpus callosum. Previously, it was unknown how the myelin sheath could be thinned and the functions of perinodal astrocytes were not well understood. These findings describe a form of nervous system plasticity in which myelin structure and conduction velocity are adjusted by astrocytes. The thrombin-dependent cleavage of neurofascin 155 may also have relevance to myelin disruption and repair.
Analysis of behavior near a cylindrical glass inclusion by scattered-light photoelasticity: Application of scattered-light photoelasticity to the determination of normal-stress differences and shearing stresses in a matrix due to an embedded circular cylinder is described and demonstrated experimentally by the author

Application of scattered-light photoelastic techniques to the determination of the normal-stress differences and shearing stresses in the matrix near an Eglass rod embedded in a polyester-resin matrix under tension is discussed. The rod is semi-infinite, that is, it extends from the center of the test section through one of the grip ends. Specific methods for making the three-dimensional scattered-light observations on the composite specimen under load are described in detail. Some typical fringe patterns are presented. Results will be useful in predicting the behavior of fibrous-glass-reinforced plastic composites since both matrix and inclusion are made of prototype materials. The system is modeled in geometric scale only.
Changing the management of refractory ventricular fibrillation: The consideration of earlier utilization of dual sequential defibrillation.

Abstract Dual Sequential Defibrillation (DSD) has shown promise in the management of refractory ventricular fibrillation (RVF). In the recent past, there have been a number of reports on the topic with varying results. Some studies have concluded that DSD provides no benefit over standard defibrillation therapy of RVF in terms of survival and neurological outcome. In fact, termination of RVF and achieving return of spontaneous circulation (ROSC) are achieved quite frequently in patients with DSD. Unfortunately, DSD has been utilized very late in the course of resuscitation, likely masking a great deal of its potential benefit. Interventions at this later phase of resuscitation are much less likely to produce a beneficial outcome, regardless of their ability to impact the course of events. It is suggested that earlier use of DSD can potentially improve ROSC, ultimate survival, and neurological outcome. After a review of the existing literature on the topic, we will propose that DSD be considered for use at a much earlier time in the resuscitation of patients with RVF. In addition to the consideration of its use in resuscitation, clinicians and device manufacturers must also address the impact on the two defibrillation devices employed in DSD due to the potential for damage and resultant defibrillator dysfunction.
Abstract LB-316: Suppression of tumor angiogenesis and metastasis by targeting a novel p38-driven tumor-stromal crosstalk

Triple-negative breast cancers (TNBCs, ER/PR/HER2-negative) pose significant clinical challenges largely due to a lack of targeted therapy. Our prior work revealed a novel tumor-stromal crosstalk that increases p38 kinase signaling in the breast tumor microenvironment (TME). Here, we examined the effects of systemic blockade of p38 signaling in the relevant TNBC models. Blockade of p38 with a selective p38 inhibitor Ralimetinib reduced tumor growth and metastasis to the lungs and liver. Histology revealed that p38 blockade greatly reduced tumor angiogenesis. Within the TME, we found a massive infiltration of myeloid cells i.e. polymorphonuclear (PMN) myeloid-derived suppressor-like cells (MDSC-like) to the lungs and liver of tumor-bearing (TB) mice. Further, TB-mice showed a significant rise in the numbers of granulocytes and monocytes in the circulation, and the accumulation of CD163+ macrophages in the TME. Blockade of p38 greatly reduced these responses. In contrast, p38 blockade increased abundance of cytotoxic CD8+ T-cells in the TME. Addressing the mechanism, we found that inactivation of p38 in tumor cells was sufficient to reduce the influx of macrophages to the tumor, suggesting a tumor-driven mechanism of mobilization or expansion of myeloid cell populations. Further, depletion of PMN-MDSC-like cells and neutrophils using anti-Ly6G antibody reduced metastases to the lungs and liver. Assessing the prognostic value of our results, we found an inverse correlation of CD163 levels with metastasis-free survival in patients with breast cancer. Together, these results demonstrate that p38 kinase promotes breast cancer growth and colonization to distant organs by regulating mobilization of pro-tumor myeloid cells. This p38-driven mechanism highlights a novel target for treatment of patients with TNBC or advanced disease. Citation Format: Andrei V. Bakin, Justin Zonneville, Rebecca Walden, Sydney Grant, Sean Colligan, Alexandra Miller, Alexander M. Truskinovsky, Scott Abrams. Suppression of tumor angiogenesis and metastasis by targeting a novel p38-driven tumor-stromal crosstalk [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-316.
Usefulness and utilization of treatment elements from the Transdiagnostic Sleep and Circadian Intervention for adolescents with an evening circadian preference.

Abstract Objective Existing research has demonstrated that patient ratings of usefulness and ratings of utilization of treatment elements are associated with treatment outcome. Few studies have examined this relationship among adolescents and with an extended follow-up. This study examined the extent to which elements of the Transdiagnostic Sleep and Circadian Intervention (TranS-C) were rated by youth as useful and utilized 6-months and 12-months after treatment. Method Participants were 64 adolescents with an evening circadian preference who were given TranS-C as a part of their participation in a NICHD-funded study. At 6-month and 12-month follow-up, they completed the Usefulness Scale, the Utilization Scale, a 7-day sleep diary assessing total sleep time (TST) and bedtime, and the Children's Morningness-Eveningness Preference Scale (CMEP). Results On average, adolescents rated treatment elements as moderately useful and they utilized the treatment elements occasionally. Ratings of usefulness were associated with TST at 6-month follow-up, but not with bedtime or CMEP. Ratings of utilization were associated with a change in bedtime from 6-month to 12-month follow-up, but not with TST or CMEP. Ratings of usefulness and utilization were associated with selected treatment outcome measures at both follow-ups. Conclusions These findings have implications for understanding mechanisms of change following treatment.
Image-charge effects on an electrostatic pendulum in mechanical equilibrium

A charged pendulum suspended in mechanical equilibrium by an insulated string and deflected by a uniform electric field was investigated theoretically and experimentally. When the uniform electric field is generated by a pair of large parallel conducting plates, there is an additional force of attraction between the pendulum and its corresponding image charges, which can dramatically affect the pendulum's equilibrium deflection. Consequently, the deflection depends non-linearly on the pendulum's net charge and the plate potentials, which results in additional unstable-equilibrium solutions, saddle-point solutions, or conditions for which no equilibrium occurs. Inclusion of this experiment within introductory and/or advanced undergraduate physics courses is discussed.
Analyzing matched sets of microbiome data using the LDM and PERMANOVA

Background: Matched-set data arise frequently in microbiome studies. For example, we may collect pre- and post-treatment samples from a set of individuals, or use important confounding variables to match data from case participants to one or more control participants. Thus, there is a need for statistical methods for data comprised of matched sets, to test hypotheses against traits of interest (e.g., clinical outcomes or environmental factors) at the community level and/or the OTU (operational taxonomic unit) level. Optimally, these methods should accommodate complex data such as those with unequal sample sizes cross sets, confounders varying within sets, as well as continuous traits of interest. Methods: PERMANOVA is a commonly used distance-based method for testing hypotheses at the community level. We have also developed the linear decomposition model (LDM) that unifies the community-level and OTU-level tests into one framework. Here we present a strategy that can be used with both PERMANOVA and the LDM for analyzing matched-set data. We propose to include an indicator variable for each set as covariates, so as to constrain comparisons between samples within a set, and also permute traits within each set, which can account for exchangeable sample correlations. The flexible nature of PERMANOVA and the LDM allows discrete or continuous traits or interactions to be tested, within-set confounders to be adjusted, and unbalanced data to be fully exploited. Results: Our simulations indicate that our proposed strategy outperformed alternative strategies in a wide range of scenarios. Using simulation, we also explored optimal designs for matched-set studies. The flexibility of PERMANOVA and the LDM for a variety of matched-set microbiome data is illustrated by the analysis of data from two real studies. Conclusions: Including set indicator variables and permuting within sets when analyzing matched-set data with PERMANOVA or the LDM is a strategy that performs well and is capable of handling the complex data structures that frequently occur in microbiome studies.
The Effect of an Electric Field on the Charge Recombination Rate of D+Q− A → DQA in Reaction Centers from Rhodobacter sphaeroides R-26

The name of the game in photosynthesis is effective charge separation across the plasma membrane of photosynthetic organisms. The main focus of this conference has been to understand this process quantitatively. In a sense one can view the different contributions from spectroscopy, x-ray structure determinations, dynamics, the effect of mutagenesis etc. as providing the experimental and theoretical frameworks upon which electron transfer (ET) theories are built. To critically test the validity of ET theories, it is important to devise experiments that focus on particular predictions of the theory. This has been done in the present work whose aim was to test the free energy dependence of electron transfer.
Viral Diversity, Evolution, and Selective Pressure

The mechanisms of norovirus evolution are complex owing to the diversity among and within norovirus genogroups and genotypes. Evolutionary and epidemiological patterns vary among norovirus groups. Evolution in GII.4 noroviruses is more well-characterized than any other group, and several potential mechanisms of evolution have been described including antigenic variation, receptor switching, and recombination. Antigenic variation and receptor switching appear to be linked, as putative neutralization sites and receptor binding sites both reside in the most surface-exposed region of the norovirus capsid. It presently appears that the patterns observed in GII.4 noroviruses cannot be widely extrapolated to other norovirus genotypes, and it is unclear to what degree each of these evolutionary mechanisms impact overall evolution in different norovirus groups. This chapter will outline what is known about the different mechanisms of norovirus evolution as well as describe what is known about evolution in GII.4 and other norovirus genotypes.
Using Implementation Science to Disseminate a Lung Cancer Screening Education Intervention Through Community Health Workers

National lung cancer screening with low dose computed tomography (LDCT) uptake is suboptimal. One factor contributing to slow uptake is lack of awareness. Trained Community Health Workers (CHWs) may be effective in increasing lung cancer screening awareness among disparate populations, however little is known about the processes necessary to scale an intervention for implementation by CHWs in a new area. We examined implementation processes with the RE-AIM framework and pilot tested a CHW-delivered lung cancer education intervention based on the Health Belief Model. We measured pre-post participant knowledge, attitudes and beliefs regarding cancer screening, lung cancer stigma, and intent to obtain LDCT screening. We used community-engaged strategies to collaborate with a local health system, to identify CHWs. CHWs were trained to recruit participants and deliver the one-session lung cancer education intervention. Seven CHWs and eight community sites participated. Participants (n = 77) were female (53%) primarily low income (62.9%); tobacco use was high (36.9%). Post intervention changes in lung cancer screening knowledge (p = < .0001), attitudes regarding lung cancer screening benefit (p = .034) and lung cancer stigma. (p = .024) We learned important lessons that will be useful in subsequent scaling. Collaborating with a local health system is a promising method to disseminate a lung cancer screening education intervention.
The Effects of Antepartum Depressive Symptoms on Postcesarean Opioid Consumption.

OBJECTIVE The study aimed to test the hypothesis that higher Edinburgh Postnatal Depression Scale (EPDS) scores are associated with increased pain scores and opioid use during postpartum hospitalization following cesarean section. STUDY DESIGN We conducted a retrospective cohort of English or Spanish-speaking women ≥18 years who had prenatal care for a singleton gestation and delivered by cesarean at ≥36 weeks within a tertiary center during 2017. Exclusions included women with fetal anomalies, intrauterine fetal demise, sickle cell disease, previously diagnosed pain disorders (e.g., chronic pain or fibromyalgia), substance use disorder (based on documented prescription or use of methadone or buprenorphine), or reoperation during hospital stay. Women without an EPDS recorded antenatally were also excluded. Major depressive symptoms (MDS) were defined as a documented antenatal EPDS ≥12. Women with and without MDS were compared, and multivariable linear regression models were generated to evaluate associations between MDS status and both pain scores and opioid use. RESULTS Of the 891 women meeting other inclusion criteria, 676 (76%) had documented antenatal EPDS scores, and 104 (15.4%) of those had MDS. Women with MDS were more likely to be use tobacco and have general anesthesia for cesarean delivery, but groups were otherwise similar. Women with MDS reported higher daily and average pain scores postpartum (2.4 vs. 1.7 average; p < 0.001). Women with MDS used more morphine milligram equivalents (MME) each day during their postpartum hospitalization, leading to a higher total MME use (121 mg [60.5-214.5] vs. 75 mg [28.5-133.5], p < 0.001). CONCLUSION We found an association between antepartum depressive symptoms and acute pain after cesarean delivery leading to increased opioid use. Given the current focus on opioid stewardship, further research into this association, exploration of tailored pain control, and determining whether treatment of antepartum MDS reduces postpartum pain, and therefore opioid use, will be of the utmost priority. KEY POINTS · Women with MDS report higher pain scores postcesarean.. · Women with MDS use more opioids postcesarean.. · Future studies are needed for the treatment of MDS..
Remdesivir for coronavirus 2019 (COVID-19): More promising but still unproven.

From December 2019 to May 22, 2020 the emerging and ever-increasing pandemic of coronavirus 19 (COVID-19) had no effective and safe treatment. Not surprisingly, remdesivir attracted worldwide attention. In a trial published online ahead of print, of 1063 patients, 541 were assigned at random to remdesivir and 522 to placebo. The primary prespecified endpoint was mean recovery time and patients assigned to remdesivir had a mean recovery time of 11 days versus 15 days for those assigned a random to placebo. (pâ¯<â¯0.001). With respect to mortality, the prespecfied secondary endpoint, 34/538 patients in remdesivir and 54/521 in placebo died after 28 days, yielding a possible 31% reduction that approached but did not achieve statistical significance (pâ¯=â¯0.059). The only other published trial of remdesivir randomized 237 patients in China. In that trial, 178 patients were assigned at random to remdesivir compared to 79 assigned to placebo. Those assigned at random to remdesivir experienced a possible but nonsignificant 23% faster time to clinical improvement of 21 days compared with 23 for those assigned to placebo [hazard ratio 1.23 [95% CI, 0·87-1.75)]. With respect to mortality there was no suggestion of any benefit. In fact, the mortality rate in those receiving remdesivir was 15% (22/150) compared with 13% (10/77) for those assigned to placebo. Ongoing randomized trials should be designed, conducted and analyzed to provide the necessary reliable data on mortality to resolve the remaining clinical uncertainties.
Enabling adoption and use of new health information technology during implementation: Roles and strategies for internal and external support personnel.

OBJECTIVE Successful technological implementations frequently involve individuals who serve as mediators between end users, management, and technology developers. The goal for this project was to evaluate the structure and activities of such mediators in a large-scale electronic health record implementation. MATERIALS AND METHODS Field notes from observations taken during implementation beginning in November 2017 were analyzed qualitatively using a thematic analysis framework to examine the relationship between specific types of mediators and the type and level of support to end users. RESULTS We found that support personnel possessing both contextual knowledge of the institution's workflow and training in the new technology were the most successful in mediation of adoption and use. Those that lacked context of either technology or institutional workflow often displayed barriers in communication, trust, and active problem solving. CONCLUSIONS These findings suggest that institutional investment in technology training and explicit programs to foster skills in mediation, including roles for professionals with career development opportunities, prior to implementation can be beneficial in easing the pain of system transition.
GenomicsBench: A Benchmark Suite for Genomics

Over the last decade, advances in high-throughput sequencing and the availability of portable sequencers have enabled fast and cheap access to genetic data. For a given sample, sequencers typically output fragments of the DNA in the sample. Depending on the sequencing technology, the fragments range from a length of 150–250 at high accuracy to lengths in few tens of thousands but at much lower accuracy. Sequencing data is now being produced at a rate that far outpaces Moore's law and poses significant computational challenges on commodity hardware. To meet this demand, software tools have been extensively redesigned and new algorithms and custom hardware have been developed to deal with the diversity in sequencing data. However, a standard set of benchmarks that captures the diverse behaviors of these recent algorithms and can facilitate future architectural exploration is lacking. To that end, we present the GenomicsBench benchmark suite which contains 12 computationally intensive data-parallel kernels drawn from popular bioinformatics software tools. It covers the major steps in short and long-read genome sequence analysis pipelines such as basecalling, sequence mapping, de-novo assembly, variant calling and polishing. We observe that while these genomics kernels have abundant data level parallelism, it is often hard to exploit on commodity processors because of input-dependent irregularities. We also perform a detailed microarchitectural characterization of these kernels and identify their bottlenecks. GenomicsBench includes parallel versions of the source code with CPU and GPU implementations as applicable along with representative input datasets of two sizes - small and large.
Ethmoid CSF Cerebrospinal Fluid Leak

Endoscopic sinus surgery (ESS) is an excellent option for addressing medically recalcitrant sinus disease. The combination of stereotactic image-guided navigation and advances in surgical techniques have transformed the procedure, allowing surgeons to perform more thorough dissection while minimizing risks. Despite these advances, iatrogenic injury during ESS accounts for 16% of anterior skull base cerebrospinal fluid (CSF) leaks, with the most common location involving the cribriform plate. In this chapter, we will discuss key aspects to consider in order to avoid injury to the skull base as well as highlight the proper steps to take if a CSF leak should occur.
The Philosophy of Biology: Aristotle and After

Beginning with Aristotle It is no longer possible to begin an account of modern philosophy of physics in modernity itself; one must go back at least to the Middle Ages. In the case of philosophical thought about living things, however, or what has recently come to be called philosophy of biology, one must go back even further – to the figure of Aristotle, who lived in the fourth century b.c.e. (384–323). For one thing, Aristotle is the only major philosopher in our tradition who is also a major biologist. One cannot read him for any length of time without seeing that his central philosophical concerns were closely related to his biological interests. Moreover, Aristotle first raised the questions that have preoccupied philosophers of biology ever since: arbitrary imposition versus “cutting nature at the joints” when it comes to naming traits and classifying kinds of organisms; purposive function versus haphazardness and accident in the distribution of traits to various kinds; mechanistic reduction versus teleology or goal-orientation in the process of embryogenesis. These topics are all explicitly formulated in Aristotle's biological treatises, which comprise no less than a quarter of the corpus of his writings that have come down to us. We must begin with Aristotle, however, not only because we find him raising issues that recur, but because Aristotle's biological way of thought forms the background of subsequent philosophy of biology.
The Hedge Algorithm for Metasearch at TREC 2006.

Aslam, Pavlu, and Savell [3] introduced the Hedge algorithm for metasearch which effectively combines the ranked lists of documents returned by multiple retrieval systems in response to a given query and learns which documents are likely to be relevant from a sequence of on-line relevance judgments. It has been demonstrated that the Hedge algorithm is an effective technique for metasearch, often significantly exceeding the performance of standard metasearch and IR techniques over small TREC collections. In this work, we explore the effectiveness of Hedge over the much larger Terabyte 2006 collection.
Rumors in Financial Markets

This paper develops a dynamic model of asset price behavior based upon the arrival and diffusion of rumors in a securities market. The model is based upon a time-homogeneous pure birth process in which the number of informed and uninformed traders varies probabilistically over time as learning occurs. Traders become informed by observing the original source of information or through communication with an individual who has ‘heard’ the information already, both of which are probabilistic events. Price changes result from trades that occur when an individual hears and acts on the information. Rumors can contain true or false information. False rumors ultimately are corrected. Results from simulating the model yield log price changes similar to actual intraday common stock returns.
Trends in glycemic control over a 2-year period in 126 US hospitals.

BACKGROUND Cross-sectional data on inpatient glucose control in a large sample of US hospitals are now available, but little is known about changes in glycemic control over time in these institutions. OBJECTIVE To evaluate trends in glycemic control in US hospitals over 2 years. DESIGN Retrospective analysis. METHODS Point-of-care blood glucose (POC-BG) test results at 126 hospitals during January to December 2007 and January to December 2009 were extracted using the Remote Automated Laboratory System-Plus (Medical Automation Systems, Charlottesville, VA), and patient-day-weighted mean glucose levels were compared. SETTING/PATIENTS Hospitalized patients. RESULTS A total of 12,541,929 POC-BG measurements from 1,010,705 patients were analyzed for 2007, and 10,659,418 POC-BG measurements from 656,206 patients were analyzed for 2009. Patient-day-weighted mean POC-BG in 2009 decreased by 5 mg/dL in the non-intensive care unit (non-ICU) data compared with that in 2007 (154 mg/dL vs 159 mg/dL, respectively; P 180 mg/dL declined from 28% to 25% in non-ICU patients (P < 0.001), but not in ICU. Decreases in patient-day-weighted mean POC-BG values in non-ICU patients were significant regardless of hospital size, type, and geographic region (all P < 0.001), but similar decreases were not found in ICU data. CONCLUSIONS In this first analysis of glucose changes in US hospitals, improvements over 2 years occurred in non-ICU patients. Ongoing analysis will determine whether this trend continues. Journal of Hospital Medicine 2013;8:121–125. © 2012 Society of Hospital Medicine
Concussion in the National Hockey League: a systematic review of the literature

Players in the National Hockey League (NHL) are often sidelined by injuries, including concussion. The acute, intermediate and long-term effects of repetitive head trauma remain a concern of many. In 1997, the NHL and NHL Players Association established the NHL-NHL Players Association Concussion Program to diagnose, assess and treat concussion via a standardized and scientific approach. Documenting and analyzing the trends, incidence and underlying mechanisms of concussion may help in devising future prevention and treatment plans for concussion in hockey in general and the NHL in particular. The purpose of this study, therefore, was to systematically review and summarize the existing published literature on the trends, incidence rates and underlying mechanisms of concussion in the NHL.
Craniopharyngioma: results of survey of the American society of pediatric neurosurgery

The best management of craniopharyngioma in children remains a controversial subject for pediatric neurosurgeons. The results of a survey completed by 11 pediatric neurosurgeons documenting outcome in 139 children is presented. There were 21 children treated with limited surgery and irradiation with a good outcome in 83%. One hundred twelve underwent an attempt at gross total resection, 30 of whom required irradiation. There was a marked difference in good outcome according to experience of surgeon, 87 vs. 52% in the radical surgery group.
The Quality of Care: How Can It Be Assessed?

Before assessment can begin we must decide how quality is to be defined and that depends on whether one assesses only the performance of practitioners or also the contributions of patients and of the health care system; on how broadly health and responsibility for health are defined; on whether the maximally effective or optimally effective care is sought; and on whether individual or social preferences define the optimum. We also need detailed information about the causal linkages among the structural attributes of the settings in which care occurs, the processes of care, and the outcomes of care. Specifying the components or outcomes of care to be sampled, formulating the appropriate criteria and standards, and obtaining the necessary information are the steps that follow. Though we know much about assessing quality, much remains to be known. (JAMA1988;260:1743-1748)
The Tropical Convective Spectrum. Part I: Archetypal Vertical Structures

Abstract A taxonomy of tropical convective and stratiform vertical structures is constructed through cluster analysis of 3 yr of Tropical Rainfall Measuring Mission (TRMM) “warm-season” (surface temperature greater than 10°C) precipitation radar (PR) vertical profiles, their surface rainfall, and associated radar-based classifiers (convective/stratiform and brightband existence). Twenty-five archetypal profile types are identified, including nine convective types, eight stratiform types, two mixed types, and six anvil/fragment types (nonprecipitating anvils and sheared deep convective profiles). These profile types are then hierarchically clustered into 10 similar families, which can be further combined, providing an objective and physical reduction of the highly multivariate PR data space that retains vertical structure information. The taxonomy allows for description of any storm or local convective spectrum by the profile types or families. The analysis provides a quasi-independent corroboration of the...
Crassulacean acid metabolism, CO2-recycling, and tissue desiccation in the Mexican epiphyte Tillandsia schiedeana Steud (Bromeliaceae).

After 23 days without water in a greenhouse, rates of nocturnal CO2 uptake in Tillandsia schiedeana decreased substantially and maximum rates occurred later in the dark period eventually coinciding with the onset of illumination. Nocturnal CO2 uptake accounted for less than half the total nighttime increase in acidity measured in well-watered plants. With increased tissue desiccation, only 11–12% of measured acid accumulation was attributable to atmospheric CO2 uptake. Plants desiccated for 30 days regained initial levels of nocturnal acid accumulation and CO2 uptake after rehydration for 10h. These results stress the importance of CO2 recycling via CAM in this epiphytic bromeliad, especially during droughts.
Acute human immunodeficiency virus (HIV) infection presenting with fever, elevated amylase/lipase, and hematologic abnormalities.

Abstract Background Many cases of acute human immunodeficiency virus (HIV) infection (AHI) present to the Emergency Department (ED). Early diagnosis allows a patient to modify their behavior and seek early treatment. The Emergency Physician should know that the antibody response may be absent. Objective We report a case of AHI and review its presentation to increase the awareness of this important diagnosis. Case Report A 20-year-old black man who had a history of sex with men initially presented to the ED with a chief complaint of blood per rectum when he passed stool, and chills for the prior few days. His work-up was normal, including a rapid HIV screen, and he was discharged. He returned 2 weeks later with constipation, fatigue, myalgias, decreased urination, chills, and a productive cough. His physical examination was unremarkable, HIV antibody test was negative, but his laboratory tests showed an elevation of creatine phosphokinase, amylase, and lipase. His blood count showed a normal hematocrit and white blood cell count, but there were juvenile and vacuolated white cells and giant platelets reported. HIV viral load was reported as > 1,000,000 copies/mL. Conclusions/Summary This case illustrates that AHI can present as a non-specific illness. Patients at risk should be screened for HIV. However, AHI can occur before there is a significant antibody response. In such cases, a viral load test may help make the diagnosis, allowing for early treatment and patient counseling.
Liability rules for toxics cleanup

Abstract This paper addresses the following question: If the objective of public policy is to promote efficiency in the markets for hazardous waste disposal, who should pay for the cleanup of unsafe (e.g., Superfund) disposal sites? It is shown that waste generators and taxpayers should share the costs of cleanup, with the cost shares being determined by the values of several parameters.
Studies of the copulatory behavior of house mice (Mus musculus)

This research had four objectives: (1) to quantify the postejaculatory interval and describe second series copulatory behavior of inbred house mice, Mus musculus, (2) to determine the effects of a change of female between ejaculatory series on subsequent behavior, (3) to provide the first description of copulatory behavior in C3H/HeJ mice, and (4) to assess the interlaboratory variability of measures of copulatory behavior of AKR/J mice. It was found that ejaculation in the second series was preceded by fewer intromissions and thrusts, and occurred in less time than in the first series. A change of female produced a dramatic facilitation of behavior in the AKR males, all of which ejaculated on a single insertion. C3H/HeJ mice display the largest number of pre-ejaculatory intromissions of any strain yet studied. Measures of copulatory behavior in AKR mice taken in different laboratories are generally comparable.
Multiple degradation phenomena in polymer electrolyte fuel cell operation with dead-ended anode

Dead-ended anode (DEA) operation of Polymer Electrolyte Fuel Cell (PEFC) can simplify the fuel cell auxiliary and reduce system cost, however durability and lifetime in this operating mode requires further study. In this work, we investigate the electrode and membrane degradations of one 50 cm2 active area fuel cell under DEA operation using a combination of post-mortem evaluation and in-situ performance evaluation protocol. We experimentally identify multiple degradation patterns using a cell which we have previously modeled and experimentally verified the spatio-temporal patterns associated with the anode water flooding and nitrogen blanketing. The change in cell voltage and internal resistance during operation and ex situ Scanning Electron Microscope (SEM) images of aged electrode/membrane are analysed to determine and characterize the degradation of the membrane electrode assembly (MEA). Chemical degradations including carbon corrosion in the catalyst layer and membrane decomposition are found after operating the cell with a DEA. Mechanical degradations including membrane delamination are also observed. Unique features of DEA operation including fuel starvation/nitrogen blanketing in the anode and uneven local water/current distribution, are considered as culprits for degradation.Copyright © 2011 by ASME
Diurnal variation in plasma corticosteroid concentration in dairy cattle.

Abstract Adrenal corticosteroid concentrations were determined by a competitve protein-binding technique in blood samples taken at various times of the day via indwelling jugular cannulae from six cows in each of three groups, pregnant nonlactating, nonpregnant lactating, and pregnant lactating. The results showed a pattern of plasma corticosteroid concentration suggestive of a daily rhythm with higher concentrations between 2:30 and 6:30 AM and lower concentrations at 8:30 PM in the three groups. Pregnancy and lactation status had no significant effect on the daily pattern, but the daily corticosteroid mean was higher in the pregnant, lactating group (.64±.05μg/l00 ml; mean±SE) than in the pregnant, nonlactating group (.50±.03 /μg/100ml).
Spectroscopic determination of the in-situ composition of epoxy matrices in glass fiber reinforced composites

Computerized infrared analysis is applied to the characterization of a glass-reinforced crosslinked polyester. The method of factor analysis determines the number of independent components which constitute the polymeric matrix. Subsequently, the spectra of those components are fitted by a least-squares criterion to spectra of the multicomponent matrix, or, if the glass spectrum is included as an additional component, to the spectra of composites. The least-squares coefficients yield the matrix composition in terms of the initial reactant composition and the extent of crosslinking.
A Dynamic Process Model of a Natural Gas Combined Cycle: Model Development With Startup and Shutdown Simulations

Research in dynamic process simulation for integrated gasification combined cycles (IGCC) with carbon capture has been ongoing at the National Energy Technology Laboratory (NETL), culminating in a full operator training simulator (OTS) and immersive training simulator (ITS) for use in both operator training and research. A derivative work of the IGCC dynamic simulator has been a modification of the combined cycle section to more closely represent a typical natural gas fired combined cycle (NGCC). This paper describes the NGCC dynamic process model and highlights some of the simulator’s current capabilities through a particular startup and shutdown scenario.
Time-Transgressive Neogene Radiolarian Events: Equatorial Indian and Pacific Oceans: ABSTRACT

Fifty radiolarian events (first or last occurrences) of Quaternary and Neogene age were identified in a transect from 5 drill sites (503, 573, 289, 586, 214) in the equatorial Indian and Pacific Oceans, extending from the Panama basin to the 90°E Ridge. Using an "absolute" chronology for each site based on correlation with the paleomagnetic time scale, we have estimated the degree of synchroneity or time-transgressiveness for each datum. Of those events that appear to be synchronous within the probable uncertainty of our estimate (ca. 0.3 m.y.), 85% are last occurrences. Of those events that are unmistakably time-transgressive (i.e., 1 m.y. or more), 75% are first occurrences in which the taxon evolves earliest in the Indian Ocean and progressively later in the weste n and eastern Pacific. This study, to our knowledge, is the first to document nonsynchroneity of microfossil events within a given latitudinal zone. If this effect proves characteristic of other microfossil groups as well (foraminifera, nannofossils, diatoms), it has important implications for biostratigraphy, geochronology, and plankton evolution. In particular, it suggests a reevaluation of events that presently define zonal boundaries, using precisely dated material, perhaps with the ultimate consequences of favoring last occurrences over first occurrences. The earlier evolution of taxa in the Indian Ocean is particularly unexpected in view of the strong westward zonal flow in low latitudes. End_of_Article - Last_Page 269------------
Chronic hepatitis C virus infection.

CHRONIC HEPATITIS C VIRUS (HCV) infection is a common worldwide problem. The infection may progress to cirrhosis with the subsequent development of complications such as ascites, encephalopathy, variceal bleeding, and hepatocellular carcinoma. Thus, early detection and therapy is of great importance. There has been substantial progress in understanding various aspects of HCV infection, including the virology, epidemiology, natural history of chronic infection, and medical therapy. The objective of this article is to provide relevant clinical information regarding the contemporary approach to patients with chronic HCV infection.
Two-dimensional Hankel theory

Abstract In this paper, a two-dimensional (2D) Hankel theory is developed. It is shown that the degree of a 2D transfer function is determinable from the rank of its Hankel matrix. The developed theorem encompasses the one-dimensional Hankel matrix as a special case. The result is useful in the computation of the greatest common divisor. It may also be useful in identification, realization, partial realization and coding problems.
An Instrumental Variable Approach for Continuous-Time Identification of an SI Engine Model for Automatic Controller Design

Instrumental variable algorithms are popular for their favorable consistency properties and ease of implementation. In this investigation an algorithm for automatic SI engine idle speed controller design uses and instrumental variable approach to perform system identification. The instrumental variable method employed here identifies the coefficients of a continuous-time model from discretely sampled data. This continuous-time model represents the engine dynamics from the bypass air valve voltage to the engine speed. To implements the identification algorithm, filtered derivative estimators approximate engine speed derivatives and an auxiliary model generates instrumental variables. These calculations are performed at each sample instant and are passed to the recursive formulation of the instrumental variable identification algorithm. Identification is performed utilizing reference step response data. A complete consistency analysis of this algorithm is included for this realization of the instrumental variable algorithm. Automatic controller design is completed based on the identified continuous-time model coefficients. As a result, the controller is parameterized based on the model coefficients and matching the transfer function of the idle speed feedback system to an open loop transfer function which represents the desired transient and steady state performance. The controller is implemented via a bumpless transfer process. Experimental results performed on a 4.6L V-8 fuel injected SI engine demonstrate the automated controller design process and the instrumental variable identification algorithm.© 2002 ASME
An experimental program in computer usage for secondary students

This paper presents an experimental program designed to introduce high school students to the use and interpretation of computer data. The program has evolved from a model research center in the Department of Sociology at California State College, Dominguez Hills. The Center is operated and administered by undergraduates and graduates as a part of their curricular experience in research methods.
Nicotine nasal spray and vapor inhaler: abuse liability assessment

Acute subjective and physiological effects were examined to provide information relevant to abuse liability of new nicotine delivery systems. Subjects (n = 12) were overnight-deprived smokers who received 0, 4, 8 and 16 active puffs from nicotine-containing cigarettes (0.1 mg per puff), 0, 1, 2 or 4 nasal sprays (0.5 mg nicotine per spray) and 0, 30, 60 and 120 vapor inhalations (estimated 0.013 mg nicotine per inhalation) in a within-subject single blinded design. While smokers clearly liked cigarette puffs, there was much less evidence of liking produced by either nasal spray or vapor inhaler; only modest elevations on a measure of good drug effects were observed. The novel delivery products engendered unpleasant effects of burning throat and nose, watery eyes, runny nose, coughing and sneezing that might be expected to limit abuse liability. Nicotine plasma level and heart rate increase was dose-related for cigarettes and nasal spray but not for vapor inhaler, indicating limited nicotine delivery with the latter device. Overall, results are consistent with the conclusion that the nicotine nasal spray and vapor inhaler are of substantially lower abuse liability than cigarettes in experienced cigarette smokers receiving initial exposure to these products.
Products of abelian hopfian groups

Let ℜ k be the variety of all nilpotent groups of class at most k . The purpose of this note is to prove the following Theorem 1. Let be a variety of groups containing ℜ 2 , let A and B be torsion-free abelian hopfian groups and let P be the free -product 2 of A and B. If P is residually torsion-free nilpotent, then P is hopfian .