cssi/SciSciGPT-SciSciNet huggingface dataset:
Bicycle use and accessibility among people experiencing homelessness in California cities

Abstract Urban residents with low (or no) incomes struggle to move through the city, given the expense of owning and operating automobiles. The spatial extent and ubiquity of automobile infrastructure contributes to transportation exclusion – the inaccessibility of the city to those experiencing poverty. In response, the urban poor develop their own means and methods of informal transportation in the public streets and open space of the city. I examine the experience of homelessness and bicycling in two California cities in order to answer the question: How does the bicycle improve (or detract from) the interactive accessibility of homeless people? Using mobile ethnographic methods and behavior mapping in the urban landscape, I observed and interacted with homeless people and their movements. Analysis of field notes and mappings shows people experiencing homelessness find an adaptable mode of transportation in the bicycle, more responsive than transit and reaching larger areas than walking. Compared to the car, the bicycle reduces the potential range of travel but increases accessibility to interactions with others within formal and informal spaces.
"They're in My Heart, Mind, and Cells": What Continuing Bonds Reveal About Social Networks

Background and objectives Research suggests that robust social networks have positive effects on peoples' well-being. An instrumental methodology for studying networks is the social convoy model, a diagram of concentric circles that illustrate network size, structure, and satisfaction. Convoys have been described as dynamic. Specifically, as people age, their convoys become stronger and smaller due to focusing on what matters most and accumulating losses. Therefore, convoys only include meaningful, living persons. The continuing bonds model posits that it is normal for people to maintain connections with the deceased. The objective of the current study was to integrate the social convoy and continuing bonds models in order to examine the presence of deceased loved ones in convoys. Research design and methods Eighteen individuals (M = 66 years), recruited via fliers and snowball sampling, participated in one semistructured interview regarding the death of a loved one and their convoy. Participants also completed a convoy model, identifying where the deceased fit (if anywhere) when they were alive and at present. Interviews were transcribed, coded, and analyzed for themes. Results Three themes emerged: communication (i.e., writing or speaking to the deceased), continuity (i.e., a continuing relationship), and reciprocity (i.e., perceived exchange of support(s)). Eighty-nine percent of participants felt their loved one's death did not change their convoy presence and 88% reported that their positioning in the convoy remained unchanged. Discussion and implications This research offers a new way to think about convoys and may prompt the development of supportive interventions for bereaved individuals.
Heightened Immune Response and Increased Risk of Infections in Pediatric Fontan Patients after Heart Transplantation

Purpose Infectious complications are a major cause of morbidity & mortality after heart transplantation (HT). Patients who have undergone Fontan palliation may have a higher susceptibility to post HT infections given thymectomy in infancy and known depletions of T-cell subsets. Methods This was a single-center, retrospective cohort analysis of pediatric patients undergoing HT for dilated cardiomyopathy (DCM) or failing Fontan physiology, who underwent post HT induction with anti-thymoglobulin (ATG). Repeat HTs and multi organ transplants were excluded. The primary endpoint was infection in the first 180 days post HT, defined as 1) positive blood, urine, or respiratory culture; 2) positive viral PCR (excluding CMV and EBV); 3) skin or wound infection; or 4) culture-negative infection if a full antibiotic course (≥ 5 days) was completed. Secondary endpoints included sensitivity to ATG as defined by 1) absolute lymphocyte (ALC) and CD3 counts after 5 doses; 2) the incidence of post transplant lymphoproliferative disorder (PTLD); and 3) rejection (>/= Grade 2R ACR or pAMR2) in the first 180 days post HT. Results From 1/2014 to 9/2019, 63 patients (30 Fontan, 33 DCM) underwent HT at a median of 15.4 (IQR 10.8, 20.1) and 11.7 (IQR 1.4, 13.6) years, respectively. The median total ATG received was 7.5 (IQR 6.7, 8.2) mg/kg vs 7.2 (IQR 4.7, 9.2) mg/kg (p=NS), respectively. The median CD3 [9 (IQR 3,14) vs 12 (IQR 6, 26); p=0.04, Figure 1A] and lymphocyte counts [172 (IQR 98, 354) vs 427 (IQR 205, 662); p=0.02] after ATG were lower in Fontan vs DCM patients. 28 patients (41%) developed at least one infection within 180 days after HT, with a higher rate of infection in Fontan patients (60% vs 24%, p=0.005; Figure 1B). There was no difference in the incidence of PTLD (10% vs 0%; p=0.1) or rejection (17% vs 27%; p=0.31) between Fontan vs DCM patients, respectively. Conclusion Compared to DCM patients, Fontan patients have a more pronounced suppression of CD3 counts after induction, as well as a higher risk of infection.
Ion Conductivity and Correlations in Model Salt-Doped Polymers: Effects of Interaction Strength and Concentration

Correlated anion and cation motion can significantly reduce the overall ion conductivity in electrolytes versus the ideal conductivity calculated based on the diffusion constants alone. Using coars...
Smooth muscle hamartoma and striated muscle hamartoma: Clinicopathologic characterization of two rare entities and literature review.

Smooth muscle hamartoma (SMH) and striated muscle hamartoma (STH) are anomalous proliferations of smooth muscle or striated muscle, respectively, in anatomic sites where these tissues are normally present. To date, only limited cases have been reported describing these lesions. In this study, we sought to characterize the clinicopathologic features of both SMH and STH. A total of 27 cases of SMH and 12 cases of STH from 1990 to 2020 were identified. SMH cases had a slight male predominance (63%) and a mean age of presentation of 20 years (range: 4 months-91 years), with a mean size of 9.3 mm (±13.3). In contrast, STH were equally distributed in gender, with a mean age of presentation of 40 years (range: 3 months-66 years) and a mean size of 5.7 mm (±3.6). SMH were more commonly located in the torso and extremities (70%) and STH in the head and neck area (92%). One case of SMH recurred after 1.1 years and in the initial diagnosis the lesion was present at the tissue edge. None of the cases of STH had a recurrence. We present the largest cohort of SMH and STH, and report the first case of a recurrent SMH, suggesting the importance of obtaining a clean margin for these lesions.
Changes in the optimal cardiac resynchronization therapy pacing configuration during physiologic stress

Abstract Background Some patients with ongoing heart failure symptoms after treatment with cardiac resynchronization therapy (CRT) demonstrate QRS prolongation during exercise. We investigated whether the optimal CRT pacing configuration changes during dobutamine stress. Methods Seven patients undergoing CRT implantation underwent invasive LV dP/dTmax measurement during CRT pacing in 10 configurations to determine the optimal baseline pacing configuration (OPC). Measurements were repeated during dobutamine infusion. Differences in mean LV dP/dTmax between pacing configurations were compared. Results Baseline OPC differed from stress OPC in 6/7 patients. The mean (SD) LV dP/dTmax obtained during dobutamine infusion was 1140 (377) mmHg/s in AAI pacing, 1458 (448) mmHg/s in the baseline OPC, and 1656 (435) mmHg/s in the dobutamine OPC (p 0.05). Conclusions The optimal CRT pacing configuration changes during dobutamine infusion while LV and RV activation timing does not. Further studies investigating the usefulness of automated dynamic changes to CRT pacing configuration according to physiologic condition may be warranted.
Caregiver Well-Being and Burden: Variations by Race/Ethnicity and Care Recipient Nativity Status.

Background and objectives Despite growing diversity among the aging population and extensive previous research on racial/ethnic minority caregivers, little research has been conducted on the potentially unique experiences and outcomes of informal caregivers of foreign-born care recipients. Using nationally representative data and the Stress Process Model, the current study examined the differences in caregiver outcomes (care burden, psychological well-being, and self-rated health) by care recipient nativity status (U.S.-born vs. foreign-born) and the extent to which caregiver outcomes vary by care recipient nativity status and caregiver race/ethnicity (non-Hispanic white, non-Hispanic black, Hispanic, and Others). Research design and methods The current study used Round 5 of the National Health and Aging Trends Study and the National Study of Caregiving (N = 1,436). We conducted ordinary least squares regression to analyze the differences in caregiver's outcomes by care recipient nativity status and caregiver race/ethnicity and to investigate the impacts of the inclusion of caregiving factors (background factors, primary stressors, secondary stressors, and resources). Results Regression analyses showed that only care burden significantly varied by care recipient nativity status after controlling for covariates. Caregivers of foreign-born care recipients reported a higher burden. However, when interactions of care recipient nativity status × caregiver race/ethnicity were introduced, non-Hispanic black and Hispanic caregivers of foreign-born care recipients were more likely to report better psychological well-being and self-rated health compared to their counterparts. Across caregiver groups, better caregiver-care recipient relationship quality and less caregiver chronic conditions were associated with less burden and better caregiver psychological well-being and self-rated health. Discussion and implications Care recipient nativity status and caregiver race/ethnicity may have complex effects on caregiving experiences. Given the observed significant interaction effects for caregiver psychological well-being and self-rated health, cultural factors may affect the extent to which these caregivers appraise their caregiving. Future research should delve into the appropriate ways to assess care stress as well as resilience among each caregiver group. Our results indicate the need for research, education, and practice that assess cultural and within-group differences among caregivers and inform needed changes to structural barriers.
MPN-400: Exploring the Molecular Grey Zone of Myeloid Neoplasms: Concurrent SRSF2 and Classic MPN Driver Mutations

Context: Myeloproliferative neoplasms (MPNs) are clonal myeloid neoplasms frequently associated with classic driver mutations in JAK2, MPL, or CALR. SRSF2 is among the most frequently mutated splicing genes in myeloid neoplasms and is known to confer a poor prognosis in patients with MPNs. Objective: We sought to explore the phenotypic features of myeloid neoplasms harboring concurrent SRSF2 and classic MPN driver mutations. Design: We identified myeloid neoplasms harboring concurrent SRSF2 and MPN-associated driver mutations. Mutation analysis was performed using next-generation sequencing (Illumina, San Diego, California). Results: Patients included 24 men and 5 women with a median age of 71 years (range, 51–84). BM fibrosis was present in all cases assessed [n=22]. Organomegaly was present in 15 patients. Relative and absolute monocytosis was present 38% of cases. Morphologic dysplasia (53.6%) and megakaryocytic hyperplasia and/or clustering (42%) were common. Twelve cases had an abnormal karyotype. Cases were classified as primary myelofibrosis (13), acute myeloid leukemia (5), chronic myelomonocytic leukemia (3), polycythemia vera (PV; 3), post-ET/PV myelofibrosis (2), MPN-unclassifiable, MDS-unclassifiable, and MDS/MPN-unclassifiable (WHO 2016). SRSF2 variants included P95H (67%), P95R (20%), P95L (6.5%), and p.P95_R102del (6.5%) with median variant allelic frequency (VAF) of 44% (range, 2–65). MPN driver mutations included JAK2 [n=20; median VAF 36% (range, 2–73)]; MPL [n=8; W515L (4), S493A (1), L629Q (1), Y591N (1), V501M (1)]; median VAF 24% (range, 5.54–88.31)]; and CALR [n=2; E396del (1), K385fs (1)]; VAF 51.34 and 57.5, respectively]. Other recurrent co-mutations included ASXL1 (n=20), TET2 (n=11), and NRAS/KRAS (n=8). Nine patients progressed to AML; the median time to transformation was 27.6 months (range 0–297.67). The median overall survival was 42.6 months, range (9.7–313.4). Five patients underwent stem cell transplant and were alive at last follow-up. Six patients had died at the time we conducted this study. Conclusions: Most neoplasms with concurrent SRSF2 and MPN-associated mutations have classic MPN-like phenotypes, but a subset of cases present as AML and MDS/MPN. BM fibrosis, morphologic dysplasia, monocytosis, organomegaly, and AML transformation are common, and overall prognosis is poor. Allogeneic HSCT may be of value in the treatment of these neoplasms.
Differentially Private Synthetic Medical Data Generation using Convolutional GANs

Deep learning models have demonstrated superior performance in several application problems, such as image classification and speech processing. However, creating a deep learning model using health record data requires addressing certain privacy challenges that bring unique concerns to researchers working in this domain. One effective way to handle such private data issues is to generate realistic synthetic data that can provide practically acceptable data quality and correspondingly the model performance. To tackle this challenge, we develop a differentially private framework for synthetic data generation using R\'enyi differential privacy. Our approach builds on convolutional autoencoders and convolutional generative adversarial networks to preserve some of the critical characteristics of the generated synthetic data. In addition, our model can also capture the temporal information and feature correlations that might be present in the original data. We demonstrate that our model outperforms existing state-of-the-art models under the same privacy budget using several publicly available benchmark medical datasets in both supervised and unsupervised settings.
Why Aren't We Achieving High Vaccination Rates for Rotavirus Vaccine in the United States?

Abstract Background Rotavirus vaccine (RV) coverage levels for US infants are Methods We surveyed nationally representative networks of pediatricians by internet/mail from April to June, 2019. Multivariable regression assessed factors associated with difficulty administering the first RV dose (RV#1) by the maximum age. Results Response rate was 68% (303/448). Ninety-nine percent of providers reported strongly recommending RV. The most common barriers to RV delivery overall (definite/somewhat of a barrier) were: parental concerns about vaccine safety overall (27%), parents wanting to defer (25%), parents not thinking RV was necessary (12%), and parent concerns about RV safety (6%). The most commonly reported reasons for nonreceipt of RV#1 by 4 to 5 months (often/always) were parental vaccine refusal (9%), hospitals not giving RV at discharge from nursery (7%), infants past the maximum age when discharged from neonatal intensive care unit/nursery (6%), and infant not seen before maximum age for well care visit (3%) or seen but no vaccine given (4%). Among respondents 4% strongly agreed and 25% somewhat agreed that they sometimes have difficulty giving RV#1 before the maximum age. Higher percentage of State Child Health Insurance Program/Medicaid-insured children in the practice and reporting that recommendations for timing of RV doses are too complicated were associated with reporting difficulty delivering the RV#1 by the maximum age. Conclusions US pediatricians identified multiple, actionable issues that may contribute to suboptimal RV immunization rates including lack of vaccination prior to leaving nurseries after prolonged stays, infants not being seen for well care visits by the maximum age, missed opportunities at visits and parents refusing/deferring.
3'-->5' exonuclease in Drosophila mitochondrial DNA polymerase. Substrate specificity and functional coordination of nucleotide polymerization and mispair hydrolysis.

A mispair-specific 3'-->5' exonuclease copurifies quantitatively with the near-homogeneous Drosophila gamma polymerase (Kaguni, L.S., and Olson, M.W. (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 6469-6473). The exonuclease and polymerase exhibit similar reaction requirements and optima, suggesting functional coordination of their activities. Under nonpolymerization conditions, the 3'-->5' exonuclease hydrolyzes 3'-terminal mispairs approximately 15-fold more efficiently than 3'-terminal base pairs on primed single-stranded DNA substrates, whereas it does not discriminate between any of three specific mispairs (dAMP:dAMP;dGMP:dGMP; dGMP:dAMP). Under polymerization conditions, gamma polymerase does not extend a 3'-terminal mispair from the "stationary" state, even in the presence of a large excess of the next correct nucleotide. Instead, 3'-terminal mispairs are hydrolyzed quantitatively by the 3'-->5' exonuclease over the reaction time course. During DNA synthesis by gamma polymerase in the "polymerization" mode, limited misincorporation and subsequent mispair extension do occur. Here, it appears that misincorporation and not mispair extension is rate-limiting. Template-primer challenge experiments suggest that the mechanism of template-primer transfer from the 3'-->5' exonuclease active site to the DNA polymerase active site is intermolecular; transfer from the exonuclease to polymerase mode appears to require dissociation and reassociation of mitochondrial DNA polymerase.
Folktales of the Jews, Volume 1: Tales from the Sephardic Dispersion

Reviewed Medium: book Year: 2006 Pages: 600 Publisher: The Jewish Publication Society ISBN: 978-0-8276-0829-0 (hard cover). Prices: $70.00 USD(hard cover).
Regulation of Expression of Thymidine Phosphorylase/Platelet-derived Endothelial Cell Growth Factor in Human Colon Carcinoma Cells

The enzyme/cytokine thymidine phosphorylase/platelet-derived endothelial cell growth factor (TP/PD-ECGF) has diverse functions within cells, including the regulation of steady-state thymidine levels, the conversion of cancer chemotherapeutic agent 5-fluorouracil to an active metabolite, and the mediation of angiogenesis in normal and malignant cells. Although the level of TP/PD-ECGF expression varies substantially among different individuals, is usually elevated in colorectal tumors compared to nonmalignant tissue, and has been shown to be directly associated with poor clinical prognosis, little is known about the mechanisms for control of TP/PD-ECGF expression. TP/PD-ECGF mRNA levels are extremely low in most cell lines in vitro, including HT29 human colon carcinoma cells. IFN-alpha and IFN-beta induced an increase in TP/PD-ECGF enzyme activity and mRNA levels. The induction of TP/PD-ECGF expression by IFN was not as strong as that of another IFN-inducible gene, 2'-5' oligoadenylate synthetase, but in contrast to 2'-5' oligoadenylate synthetase, TP/PD-ECGF mRNA levels remained elevated for up to 72 h. Experiments suggested that this was due to the combination of a rapid but transient increase in the rate of TP/PD-ECGF transcription that was accompanied by a more prolonged stabilization of TP/PD-ECGF mRNA. Using an electrophoretic mobility shift assay, IFN was found to rapidly and transiently induce nuclear factors that bound to a putative IFN response element in the TP/PD-ECGF promoter. The complex observed was similar but not identical to that seen using the consensus IFN-stimulated response element sequence as a target. TP/PD-ECGF mRNA also has a pyrimidine-rich sequence at its 3' end that was similar to a motif that has been reported to mediate increased mRNA stability in other genes. These studies indicate that TP/PD-ECGF gene expression was subject to regulation by both transcriptional and posttranscriptional mechanisms.
The Importance of the Cremasteric Reflex in Acute Scrotal Swelling in Children

The correlation between the presence of the ipsilateral cremasteric reflex and the absence of testicular torsion was 100 per cent in a 7-year evaluation of 245 boys with acute scrotal swelling. The presence of the cremasteric reflex was the most valuable clinical finding in ruling out testicular torsion and the absence of this reflex increased the suspicion of testis torsion.
Robots and manipulators

Robots are defined and described for various applications. The key feature of robots is programmability, which allows teleoperation, repair work in hazardous situations, and unsupervised operation in industrial functions. Two types of robots now exist: special purpose, with equipment for a specific task; and general purpose, which include nonservo-controlled robots, servo-controlled robots, and sensory control robots. Sensory robots are the most sophisticated, and are equipped with both internal control sensors and external sensors such as TV cameras, pressure detectors, laser range finders, etc. Sensory feedback to a central computer enables the robots to make appropriate modifications to the control program to adapt to new situations. Pattern recognition and scans for size are features of the TV sensors, and programs to develop a universal effector (hand) are outlined. Finally, robot programming in terms of manual, walkthrough, and textual methods are described, and the potential uses of robots for space and undersea construction and repair are discussed.
Growth and Competition in Renewable Energy Industries: Insights from an Integrated Assessment Model with Strategic Firms

Abstract This article describes the development, implementation, and application of an integrated assessment modeling framework featuring renewable technology markets with producers engaged in Cournot competition. Scenario results reveal how climate policy and inter-firm learning spillovers interact with market structure to affect wind and solar PV prices, adoption, producer profits, and carbon emissions. Competitive markets yield consistently lower markups than concentrated markets, leading to significantly more adoption and lower emissions. Widespread solar PV adoption is a key component of the largest emissions reductions, but this requires substantial price reductions that only occur if the solar PV market is competitive and learning spills over across producers. Whether a leading firm has a profit incentive to facilitate or obstruct learning spillovers depends on the availability of cost-competitive substitute technologies. If such a substitute exists, the firm prefers strong spillovers that help its industry compete against the substitute; if not, the firm prefers weak spillovers that prevent competitors in its industry from seizing market share. The relationship between price and cumulative capacity is endogenous in the modeling framework. Regression analysis of scenario results yields price learning rates which are similar to unit production cost learning rates in competitive markets, but substantially lower – even negative – in concentrated markets.
The effect of altitude on the operation performance of low voltage switchgear and controlgear components

Decreased air density due to increased altitude can have an effect on the operation performance of low-voltage switchgear and controlgear components. For applications at high altitude, little is known about this effect on the operation performance of these components. Characteristics such as dielectric voltage withstand, thermal ampacity, overload calibration, contact life, and interruption capability can be affected by the decreased air density. Tests were conducted in an electrical laboratory capable of producing needed electrical circuit parameters. The testing was conducted using a vacuum chamber to artificially lower the air density to simulate altitudes up to 6000 m. A fact-finding study was developed, defining the operation performance capabilities for low-voltage components at higher altitudes.
Transforming growth factor type β is a specific inhibitor of 3T3 T mesenchymal stem cell differentiation

Abstract In the current studies we examined the effects of transforming growth factor type β (TGF-β) on the control of differentiation of BALB/c 3T3 T stem cells. We report that TGF-β is a potent, reversible inhibitor of adipocyte differentiation (50% inhibition at ~0.06–0.08 ng/ml), while other biologically active polypeptides, such as epidermal growth factor (EGF), human growth hormone (hGH), and somatomedin C, have no specific effect on differentiation at even higher concentrations (200 ng/ml). We also report that TGF-β inhibits differentiation in a cell cycle-dependent manner by its effect on a specific phase in the differentiation process. We therefore suggest that if TGF-β is an important regulatory factor, one of its critical mechanisms of action may be its ability to inhibit the process of cell differentiation.
Characterization of mixing performance for bio-mimetic silicone cilia

This article presents the mixing performance of bio-mimetic cilia in a circular microchamber that is compatible with microwell plates. The mixing performance is characterized and compared with those of both diffusion- and vibration-induced mixers. To represent the mixing performance, the 90% mixing time, which was the time span for 90% mixing completion, was measured by analyzing the mixing process of black ink with water. The cilia mixer reduced the 90% mixing time by 8.0- and 1.4 times compared with those of the diffusion- and vibration mixers, respectively. In addition, the coefficient of variation of the 90% mixing time for the cilia mixer was reduced by 3.1- and 2.8 times compared with those of the diffusion- and vibration mixers, respectively. The experimental mixing performance was validated by numerical analysis. The simulations showed that the cilia mixer could significantly reduce the coefficient of variation because the convective flows generated by the cilia rapidly increased the surface area of the ink and thus rapidly decreased the variations in the initial mixing conditions.
Implicit masking constrained by spatial inhomogeneities

Human contrast sensitivities to gratings were measured within windows of 3, 9.1 and 61.5 deg at spatial frequencies down to the nominal frequency of 0 c/deg (i.e., a uniform field), and the resulting curves were related to the Fourier spectra of the corresponding windows and of spatial inhomogeneities in the visual pathway. The data show that sensitivity approaches an asymptote about 1.5 log units below peak sensitivity as spatial frequency decreases, the so-called low frequency cut. Computations show that the fundamentals of the test fields used here were detected and not their harmonics, and control experiments suggest that the edges of the gratings did not affect detection of the gratings. Most of the low frequency cut could be attributed to masking by the harmonics of the windows within which the gratings were introduced. The added contribution of the inhomogeneities in the retinal distribution of cones accounts for the remainder of the low frequency cut observed with the two smaller windows, and adding the effects of the inhomogeneities to the distribution of parvocellular ganglion cells accounts for the remainder of the low frequency attenuation with the largest field. Therefore, the attenuation of sensitivity to low frequencies that gives the contrast sensitivity curve its bandpass shape can be attributed entirely to implicit masking, i.e., to masking by the Fourier spectrum of the window within which the test grating is presented, after further spreading by retinal inhomogeneities.
A Probabilistic Query Suggestion Approach without Using Query Logs

Commercial web search engines include a query suggestion module so that given a user's keyword query, alternative suggestions are offered and served as a guide to assist the user in formulating queries which capture his/her intended information need in a quick and simple manner. Majorityof these modules, however, perform an in-depth analysis oflarge query logs and thus (i) their suggestions are mostlybased on queries frequently posted by users and (ii) theirdesign methodologies cannot be applied to make suggestions oncustomized search applications for enterprises for which theirrespective query logs are not large enough or non-existent. To address these design issues, we have developed PQS, aprobabilistic query suggestion module. Unlike its counterparts, PQS is not constrained by the existence of query logs, sinceit solely relies on the availability of user-generated contentfreely accessible online, such as the Wikipedia.org documentcollection, and applies simple, yet effective, probabilistic-andinformation retrieval-based models, i.e., the Multinomial, BigramLanguage, and Vector Space Models, to provide usefuland diverse query suggestions. Empirical studies conductedusing a set of test queries and the feedbacks provided byMechanical Turk appraisers have verified that PQS makesmore useful suggestions than Yahoo! and is almost as goodas Google and Bing based on the relatively small difference inperformance measures achieved by Google and Bing over PQS.
Integration in the complex plane

IN the first article of this series Professor J. B. Russell1 gave a survey of Heaviside's direct operational calculus. This direct calculus has proved to be very successful. It may be applied to a large class of problems concerning differential equations of transients. Nevertheless there has been much criticism about the validity of the operational method. The theory of complex integration, the topic of the present article, is the main tool which permits us to put Heaviside's calculus on a solid basis. Aside from this justification, however, complex integration is an indispensable tool for any advanced mathematical treatment of transient problems, transmission problems, or related problems in electrical theory.
Computing the signal subspaces of a sparse and/or structured matrix

Many techniques involve the computation of singular subspaces associated with an extreme cluster of singular values of an m X n data matrix A. Frequently A is sparse and/or structured, which usually means matrix-vector multiplications involving A and its transpose can be done with much less than (sigma) (mn) flops, and A and its transpose can be stored in static data structures with much less than (sigma) )(mn) storage locations. Standard complete orthogonal decompositions may be unattractive due to the computational and dynamic storage overhead associated with the initial preprocessing of the data. We describe an efficient Matlab implementation of the low-rank ULV algorithm for extracting reliable and accurate approximations to the singular subspaces associated with the cluster of large singular values without altering the matrix. The user can choose any principal singular vector estimator to underwrite the algorithm, may call a specialized routine to compute matrix-vector products involving A and its transpose, and can choose the desired level of accuracy of a residual. The main computational savings stems from preserving A and avoiding the explicit formation of unwanted information.
Seizure Following Brief Exposure to the Insect Repellent N,N-Diethyl-m-Toluamide

A 5-year-old boy with a history of mild developmental delay experienced a major motor seizure at day camp after topical application that morning of the insect repellent Muskol ® and a later application of OFF ® [both contain N,N -Diethyl-m-toluamide (DEET)]. The patient continued convulsing in the emergency department and was treated with diazepam. Laboratory tests were unremarkable, as were lumbar puncture, computed tomography scan, and blood cultures. Skin decontamination was performed. DEET levels in the urine were 0.003 μg/mL. Although seizures and encephalopathic syndrome have been described with DEET in previous case reports involving topical exposure of pediatric patients, atypical aspects with regard to this case include that this patient was a male (most other case reports involve females), exposure was relatively brief compared with other reports, and the patient developed seizures without a prodrome described in previous reports. Avoidance of high-concentration DEET formulations in pediatric patients should be considered.
Beyond a bed: Support for positive development for youth residing in emergency shelters

Abstract This study examines environmental and personal characteristics that support positive development among youth residing in emergency shelters. The Developmental Assets Profile (DAP; Search Institute 2005 ) was used to measure external and internal developmental assets and adapted to additionally measure agency assets, i.e., external assets specific to the shelter setting. Eighty-two youth completed the DAP and additional measures of psychosocial functioning (distress, life satisfaction, health behavior, program satisfaction, caregiver relationships, and academic functioning) during shelter stay. At admission, youth asset scores were positively correlated with measures of healthy functioning. Youth ratings for agency assets were significantly higher than external asset ratings. Youth completing multiple surveys reported decreases in distress and increases in life satisfaction, health behavior, positive caregiver relationship, and internal assets during shelter stay. Results extend research on developmental assets and underscore the value of opportunities for positive development among homeless youth and the agencies that serve them.
Structure of the MLL CXXC domain-DNA complex and its functional role in MLL-AF9 leukemia

The gene MLL (encoding the protein mixed-lineage leukemia) is the target of chromosomal translocations that cause leukemias with poor prognosis. All leukemogenic MLL fusion proteins retain the CXXC domain, which binds to nonmethylated CpG DNA sites. We present the solution structure of the MLL CXXC domain in complex with DNA, showing how the CXXC domain distinguishes nonmethylated from methylated CpG DNA. On the basis of the structure, we generated point mutations that disrupt DNA binding. Introduction of these mutations into the MLL-AF9 fusion protein resulted in increased DNA methylation of specific CpG nucleotides in Hoxa9, increased H3K9 methylation, decreased expression of Hoxa9-locus transcripts, loss of immortalization potential, and inability to induce leukemia in mice. These results establish that DNA binding by the CXXC domain and protection against DNA methylation is essential for MLL fusion leukemia. They also provide support for viewing this interaction as a potential target for therapeutic intervention.
The Rashba effect and non-Abelian phases in quantum wire devices

We present a 2D method for studying quantum transport through arbitrary geometries under the influence of both external magnetic fields and Rashba spin-orbit coupling. We apply this method to two geometries—a straight wire and a ring structure. Our results reveal the precession of spin-polarized modes in the straight wire, and conductance resonances in the ring due to phase shifts from the magnetic field and from the Rashba effect. The conductance resonances arising from the Rashba effect are due to the non-Abelian nature of the phase shifts acquired by electrons propagating around the ring.
Lesions of the ventral striatum mimic the effect of olfactory bulbectomy to prevent short photoperiod-induced testicular regression in golden hamsters

Abstract Bilateral olfactory bulbectomy (BX) or bilateral transection of the rostral lateral olfactory tract (LOT) at the level of the anterior olfactory nucleus markedly increases gonadotropin secretion and prevents the testicular regression associated with maintenance on short photoperiod in golden hamsters. In an effort to further elucidate the neural tracts involved in this influence on gonadotropin secretion, lesions were placed in several potential pathways. Hamsters underwent sham surgery (SH), bilateral BX, or electrolytic or radiofrequency lesions of the: medial nucleus of the amygdala (MeX) caudal LOT just rostral to the medial nucleus of the amygdala (LOTX); or ventral striatum (VSX). Lesions were either bilateral or unilateral with contralateral olfactory bulbectomy. All animals were then placed on short photoperiod (LD 10:14) for 10 weeks and testicular size and body weight were assessed at weekly intervals. Lesion placement was assessed in brain sections stained with cresyl violet and animals with misplaced lesions were excluded. The following represent the number of animals in each group undergoing testicular regression in response to short photoperiod: SH: 32/35; BX: 8/31 ( P ); MeX: 5/5; caudal LOTX: 8/9 and VSX: 3/8 ( P ). Serum LH, FSH and testosterone at the end of the study correlated with the testicular regression data. These results suggest that the tonic inhibitory effect of the olfactory bulbs on gonadotropin secretion is mediated by fibers that exit the LOT rostral to the amygdala and project medially, either passing through or synapsing in the ventral striatum.
Summary of post-symposium evaluations from 1991 SIGCSE technical symposium on computer science education

The 1991 SIGCSE Technical Symposium was held March 7-8, 1991, in San Antonio, Texas. A post-symposium evaluation form was made available to all attendees, with the request that it be filled out to assist the '91 committee in evaluating the current symposium and to help future committees in planning their symposia. This article highlights the responses to the evaluation forms and includes excerpts from the chair report, the registration report, and the treasurer's report.
An experiment in high-precision arithmetic on shared memory multiprocessors

The task of verifying a result in computational number theory became a study in the parallel computation of high precision arithmetic, providing information that can be used to intelligently make decisions about the implementation of an arbitrary-precision integer arithmetic package for shared memory multiprocessors.
Training domestic dogs (Canis lupus familiaris) on a novel discrete trials odor-detection task

Abstract Dogs can be trained to reliably detect a wide variety of odors. Little scientific research, however, has been published on the rate at which dogs can learn to detect an odor, the variables influencing this rate, and how this rate may vary across dogs. In two experiments, we developed a procedure that allows the study of individual differences in the acquisition of an odor detection task in dogs. We demonstrate that differential reinforcement can be used to train a rooting response in a bin under the control of a novel odorant in discrete trials. In initial testing, we showed that as a group, twenty dogs performed significantly above chance within 24 trials, with two dogs meeting an individual criterion for above chance performance. In a follow-up experiment, we compared burying accessible food inside the target bin (with inaccessible food in the non-target bin) to the experimenter delivering food by hand following correct responses. We assessed the effect of this procedural variation on both an odor discrimination and a visual discrimination. Dogs learned faster on the odor task when the experimenter delivered food, compared to when food was placed directly in the bins. Performance on the visual task was lower than on the odor task and was unaffected by how food was delivered. Our discrete-trials procedure with experimenter-delivered food may be a useful method to study rapid acquisition of an odor-detection in dogs.
Precursors of protoporphyrin in Chlorella.

ON the basis of studies of Chlorella mutants a biosynthetic chain has been formulated leading from protoporphyrin through Mg protoporphyrin, Mg vinyl pheoporphyrin and protochlorophyll finally to chlorophyll1. We have recently isolated a Chlorella mutant which promises to reveal some of the precursor porphyrins leading up to protoporphyrin.
Confirmatory Factor Analysis of Word Recognition and Process Measures in the Colorado Reading Project

Measures of word recognition (REC) and two component skills, phonological coding (PHON) and orthographic coding (ORTH), were subjected to multivariate behavioral genetic analysis. Data were obtained from a sample of identical and fraternal twin pairs wherein at least one member of each pair was reading disabled (RD), and from a sample of twins wherein both members of each pair read in the normal range. Confirmatory factor analysis was used to fit the genetic, common environmental, and specific environmental covariance components for REC, PHON, and ORTH within the RD and normal simples. The resulting heritability estimates for REC, PHON, and ORTH were 0.59, 0.41, and 0.05 in the RD sample, and 0.35, 0.52, and 0.20 in the normal sample. After dropping the nonsignificant common environment parameters from the models, the genetic correlations between REC and PHON and between REC and ORTH were respectively 0.81 and 0.45 in the RD sample, and 0.68 and 0.45 in the normal sample. Differences between the genetic correlations were significant in the RD sample (p<0.005), marginally significant in the normal sample (p<0.10), and highly significant in the combined sample (p<0.001), indicating that genetic influences on individual differences in REC are more strongly related to genetic variance in PHON than in ORTH. These results are consistent with previous demonstrations of substantial genetic covariance between the disabled group's deficits in REC and PHON, but not between REC and ORTH (Olson et al., 1989; Olson and Rack, 1990).
Conformational dynamics of human FXR-LBD ligand interactions studied by hydrogen/deuterium exchange mass spectrometry: Insights into the antagonism of the hypolipidemic agent Z-guggulsterone

Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily of transcription factors that plays a key role in the regulation of bile acids, lipid and glucose metabolisms. The regulative function of FXR is governed by conformational changes of the ligand binding domain (LBD) upon ligand binding. Although FXR is a highly researched potential therapeutic target, only a limited number of FXR-agonist complexes have been successfully crystallized and subsequently yielded high resolution structures. There is currently no structural information of any FXR-antagonist complexes publically available. We therefore explored the use of amide hydrogen/deuterium exchange (HDX) coupled with mass spectrometry for characterizing conformational changes in the FXR-LBD upon ligand binding. Ligand-specific deuterium incorporation profiles were obtained for three FXR ligand chemotypes: GW4064, a synthetic non-steroidal high affinity agonist; the bile acid chenodeoxycholic acid (CDCA), the endogenous low affinity agonist of FXR; and Z-guggulsterone (GG), an in vitro antagonist of the steroid chemotype. A comparison of the HDX profiles of their ligand-bound FXR-LBD complexes revealed a unique mode of interaction for GG. The conformational features of the FXR-LBD-antagonist interaction are discussed.
Studies with 1,2-dithiole-3-thione as a chemoprotector of hydroquinone-induced toxicity to DBA/2-derived bone marrow stromal cells

Abstract Stromal cells from DBA/2 mouse bone marrow have been shown to be susceptible to cytotoxicity induced by several redox-active metabolites of benzene, including hydroquinone (HQ). Treatment with HQ also alters the composition of stromal cell populations by preferentially killing stromal macrophages compared to stromal fibroblasts. This cytotoxicity can be prevented by 1,2-dithiole-3-thione (DTT) as a result of the induction of quinone reductase (QR), a quinone-processing enzyme, and glutathione. The inductive activities of DTT protected stromal cells against HQ-induced cytotoxicity and against HQ-induced impairment of stromal cell ability to support myelopoiesis. In vivo feeding of DTT to DBA/2 mice increased QR activity within the bone marrow compartment and protected bone marrow stromal cells isolated from the DTT-fed animals from ex vivo HQ challenge. Thus, the inducibility of cellular defense mechanisms and xenobiotic-processing enzymes by chemoprotective agents such as DTT may be a useful strategy for protecting against chemically induced bone marrow toxicities.
Using online crowdsourcing to understand young adult attitudes toward expert-authored messages aimed at reducing hazardous alcohol consumption and to collect peer-authored messages

Text message delivered prevention interventions have the potential to improve health behaviors on a large scale, including reducing hazardous alcohol consumption in young adults. Online crowdsourcing can be used to efficiently develop relevant messages, but remains largely understudied. This study aims to use online crowdsourcing to evaluate young adult attitudes toward expert-authored messages and to collect peer-authored messages. We designed an online survey with four drinking scenarios and a demographic questionnaire. We made it available to people who reported age 18–25 years, residence in the US, and any lifetime alcohol consumption via the Amazon Mechanical Turk crowdsourcing platform. Participants rated 71 sample text messages on instrumental (helpful) and affective (interesting) attitude scales and generated their own messages. All messages were coded as informational, motivational, or strategy facilitating. We examined differences in attitudes by message type and by drinking status and sex. We surveyed 272 participants in 48 h, and 222 were included in analysis for a total participant payment cost of $178. Sample mean age was 23 years old, with 50 % being female, 65 % being of white race, and 78 % scored as hazardous drinkers. Informational messages were rated the most helpful, whereas motivational messages were rated the most interesting. Hazardous drinkers rated informational messages less helpful than non-hazardous drinkers. Men reported messages less helpful and interesting than women for most categories. Young adults authored 161 messages, with the highest proportion being motivational. Young adults had variable instrumental and affective attitudes toward expert-authored messages. They generated a substantial number of peer-authored messages that could enhance relevance of future alcohol prevention interventions.
The e-equilibrium in transportation networks

Abstract The principle of traffic equilibrium (Wardrop, 1952) demands that the trip makers have enough knowledge of transportation networks, which needs to be attained by accumulating experiences for a long time. Because of the complexity of traffic situation in the networks, the route choice decisions for trip makers are, however, not always optimal objectively. As a consequence, it is impossible to strictly attain Wardrop equilibrium. In this paper, a new concept of equilibrium, ϵ-equilibrium is proposed under the realistic assumption, i.e., the fuzzy road information and random route choices. ϵ-equilibrium in the network is discussed by adopting fuzzy set theory, mixed stochastic Games and Brouwer fixed point theorem in topological space. The conclusion is that there is ϵ-equilibrium in the real transportation network and this ϵ-equilibrium has some deviations from the strict Wardrop equilibrium. The notion of ϵ-equilibrium extends the traditional notion of network equilibrium. It shows that traffic flow in the network converges to a region rather than to the points.
A study on dental vacuum system losses

An experimental study was conducted to document system head losses for dental vacuum systems. Experiments were performed to estimate pressure losses and pressure loss coefficients for pertinent dental treatment room hoses and fittings in high-volume evacuation systems. Pressure losses for some polyvinyl chloride (PVC) elbows used in dental plumbing systems were also measured and presented. Friction head losses in straight PVC piping are calculated and documented in graphical form. Calculated values for friction losses are found to correlate exceptionally well with measured experimental data.