cssi/SciSciGPT-SciSciNet huggingface dataset:
Predictors for under-prescribing antibiotics in children with respiratory infections requiring antibiotics.

Abstract Background/objective Previous studies showed variability in the use of diagnostic and therapeutic resources for children with febrile acute respiratory tract infections (ARTI), including antibiotics. Unnecessary antibiotic use has important public and individual health outcomes, but missed antibiotic prescribing also has important consequences. We sought to determine factors associated with antibiotic prescribing in pediatric ARTI, specifically those with pneumonia. Methods We assessed national trends in the evaluation and treatment of ARTI for pediatric emergency department (ED) patients by analyzing the National Hospital Ambulatory Medical Care Survey from 2002 to 2013. We identified ED patients aged ≤ 18 with a reason for visit of ARTI, and created 4 diagnostic categories: pneumonia, ARTI where antibiotics are typically indicated, ARTI where antibiotics are typically not indicated, and “other” diagnoses. Our primary outcome was factors associated with the administration or prescription of antibiotics. A multivariate logistic regression model was fit to identify risk factors for underuse of antibiotics when they were indicated. Results We analyzed 6461 visits, of which 10.2% of the population had a final diagnosis of pneumonia and 86% received antibiotics. 41.5% of patients were diagnosed with an ARTI requiring antibiotics, of which 53.8% received antibiotics. 26.6% were diagnosed with ARTI not requiring antibiotics, of which 36.0% received antibiotics. Black race was a predictor for the underuse of antibiotics in ARTIs that require antibiotics (OR: 0.72; 95% CI: 0.58–0.90). Conclusions For pediatric patients presenting to the ED with pneumonia and ARTI requiring antibiotics, we found that black race was an independent predictor of antibiotic underuse.
Common effects of attractive and repulsive signaling: Further analysis of Mical-mediated F-actin disassembly and regulation by Abl

ABSTRACTTo change their size, shape, and connectivity, cells require actin and tubulin proteins to assemble together into long polymers – and numerous extracellular stimuli have now been identified that alter the assembly and organization of these cytoskeletal structures. Yet, there remains a lack of defined signaling pathways from the cell surface to the cytoskeleton for many of these extracellular signals, and so we still know little of how they exert their precise structural effects. These extracellular cues may be soluble or substrate-bound and have historically been classified into two independently acting and antagonistic groups: growth-promoting/attractants (inducing turning toward the source of the factor/positive chemotropism) or growth-preventing/repellents (turning away from the source of the factor/negative chemotropism). Paradoxically, our recent results directly link the action of growth factors/chemoattractants and their signaling pathways to the promotion of the disassembly of the F-actin ...
A Case for a More Effective, Power-Efficient Turbo Boosting

Single-thread performance and throughput often pose different design constraints and require compromises. Mainstream CPUs today incorporate a non-trivial number of cores, even for mobile devices. For power and thermal considerations, by default, a single core does not operate at the maximum performance level. When operating conditions allow, however, commercial products often rely on turbo boosting, which temporarily increases the clock frequency to increase single-thread performance. However, increasing clock speed may result in a poor performance return for invested energy. In this article, we make a case for a more effective boosting strategy, which invests energy in activities with the best estimated return. In addition to running faster clocks, we can also use a look-ahead thread to overlap the penalties of cache misses and branch mispredicts. Overall, for similar power consumptions, the proposed adaptive turbo boosting strategy can achieve about twice the performance benefits while halving the energy overhead.
Examining e-Health Literacy and the Digital Divide in an Underserved Population in Hawai‘i

Seeking health information is one of the leading uses for the Internet and World Wide Web (WWW). Research has found the amount one benefits from e-Health information (health information from electronic sources) is directly related to the level of e-Health literacy. e-Health literacy is defined as "the ability to seek, find, understand, and appraise health information from electronic sources and apply the knowledge gained to addressing or solving a health problem." In order to gain a further understanding of the effects and use of technology, the digital divide, and the relationship between technology utilization and health outcomes, focus group interviews were conducted with participants diagnosed with diabetes and currently residing in a Medically Underserved Area. Overall, 25 volunteers participated in the four focus group meetings. Based on the focus group discussions, a general low e-Health literacy rate was identified. This was demonstrated by the lack of access to the Internet and the skills needed to retrieve health information. Of the 25 participants, 64% reported having Internet access at some level, but, only one reported going on the Internet every day. When the barriers to using the Internet were discussed, many participants expressed a lack of knowledge in how to retrieve information. Results of this study further show that having access to technology is not necessarily associated with usage. This dynamic is evolving into a new form of digital divide, gap in information retrieval and usage, versus gap in access. This is the first known study to examine e-Health literacy in an underserved population in Hawai'i. With the proliferation of information and communication technology and the transformation of information retrieval to be mobile and "on demand", a multi-pronged communication and education strategy is needed to explore how technology can improve e-Health literacy and health outcomes among underserved populations.
Racial disparities in the proportion of needed services maltreated children received

Abstract This secondary analysis of data describing 1186 maltreated children, drawn from the National Survey of Child and Adolescent Well-Being II, examined racial disparities in their access to and receipt of needed services and in their caseworkers' case planning and engagement with caregivers. We used generalized least squares random-effects modeling for panel data, separately with 3 ethnicity subsamples, to estimate associations between proportion of needed services received and several explanatory variables. Children in these subsamples had been substantiated for maltreatment and had had at least one needed service identified by a caseworker. Results showed Hispanic children to receive proportionally fewer needed services versus White children. Moreover, across all subsamples, proportion of needed services received was associated negatively with client refusal of services and positively with interview wave. Results showed that proportionally more needed services were received by the subsample of 719 African American children living in poverty, relatively young, able to access services with little difficulty, and associated with case plans identifying relatively more needed services. For the subsample of 712 Hispanic children, negative associations were observed between services receipt and perceived collaborative engagement with caseworker reported by caregiver, as well as with service unavailability and with difficulty accessing services. Finally, results for the subsample of 720 White children who were physically maltreated and experienced service unavailability showed them to receive proportionally fewer needed services; however, White children whose case plans included needed services received proportionally more services. Implications for child welfare services and for caseworkers are discussed.
Arnold-chiari malformation

Arnold-Chiari malformations (ACM) are a group of congenital disorders defined by downward displacement of cerebellar tonsils, and possibly the brainstem, through the foramen magnum. Type 1 ACM is the most frequent of the Chiari malformations and is characterized by a ≥5 mm tonsillar descent below the foramen magnum. Headache is the most common presenting symptom, however many patients are asymptomatic. This congenital anatomic variation can lead to potentially challenging obstetric and anesthetic implications during pregnancy and delivery, such as a greater risk for increased intracranial pressure. Although literature discussing ACM management in pregnancy and delivery is scarce and controversial, both neuraxial and general anesthetic techniques have been described safely. However, neither technique is without significant potential risk. The delivery and anesthetic plan for each parturient with ACM must be formulated individually at a multidisciplinary center utilizing a team approach with the patient, obstetrician, anesthesiologist and neurosurgeon.
Nitrogen-doped graphene quantum dots: Optical properties modification and photovoltaic applications

In this work, we utilize a bottom-up approach to synthesize nitrogen self-doped graphene quantum dots (NGQDs) from a single glucosamine precursor via an eco-friendly microwave-assisted hydrothermal method. Structural and optical properties of as-produced NGQDs are further modified using controlled ozone treatment. Ozone-treated NGQDs (Oz-NGQDs) are reduced in size to 5.5 nm with clear changes in the lattice structure and ID/IG Raman ratios due to the introduction/alteration of oxygen-containing functional groups detected by Fourier-transform infrared (FTIR) spectrometer and further verified by energy dispersive X-ray spectroscopy (EDX) showing increased atomic/weight percentage of oxygen atoms. Along with structural modifications, GQDs experience decrease in ultraviolet–visible (UV–vis) absorption coupled with progressive enhancement of visible (up to 16 min treatment) and near-infrared (NIR) (up to 45 min treatment) fluorescence. This allows fine-tuning optical properties of NGQDs for solar cell applications yielding controlled emission increase, while controlled emission quenching was achieved by either blue laser or thermal treatment. Optimized Oz-NGQDs were further used to form a photoactive layer of solar cells with a maximum efficiency of 2.64% providing a 6-fold enhancement over untreated NGQD devices and a 3-fold increase in fill factor/current density. This study suggests simple routes to alter and optimize optical properties of scalably produced NGQDs to boost the photovoltaic performance of solar cells.
Cancer Stem Cells in Resistance to Cytotoxic Drugs: Implications in Chemotherapy

The efficacy of cytotoxic chemotherapy is limited by drug resistance presented by some cancer cells. Cancer stem cells (CSCs) are a sub-population of tumor cells that can initiate tumor formation. If chemotherapy kills bulk of cells within a tumor but not CSCs, the surviving CSCs can initiate the formation of recurrent tumors. This article discusses the inherent resistance of CSCs toward cytotoxic chemotherapy and some possible mechanisms involved. Approaches to target CSCs to improve the efficacy of chemotherapy will also be discussed.
Hybrid Electrodes Efficient for Both Electrowetting and Dielectrowetting

This paper reports hybrid electrodes efficiently working for both electrowetting on dielectric (EWOD) and dielectrowetting. Virtually all kinds of liquid droplets, no matter which are conductive or dielectric, can be manipulated on these electrodes in an open environment without changing the electrode shape, electric signal form, or physical configuration. In addition, these electrodes are integrated with a slippery liquid infused porous surface (SLIPS) in order to minimize friction and biofouling. This electrode platform was experimentally confirmed effective for conductive liquids (water, protein solution, detergent and saline) for EWOD as well as dielectric liquids (dodecane, silicone oil, light and heavy crude oil) for dielectrowetting
Articulatory effects on speech perception: a second report

Abstract: The effects of repeated articulation on speech perception were assessed to determine whether the production and perception of speech rely on the same processing mechanism. Subjects were asked to whisper an alternating sequence of syllables repetitively, in the absence of auditory feedback, and were then presented syllables to identify auditorily. In the first experiment, subjects uttered a sequence of the syllables [si]–[su] or [sti]–[stu] and then identified a series of seven synthetic speech syllables spanning the distinction between [si] and [sti]. These syllables varied from one another in the duration of silence preceding the vowel. A significant effect of perceptuo-motor adaptation was obtained for [sti]-[stu] but not [si]–[su] articulation. In Experiment II, the same test procedure was applied to another series of synthetic syllables, [ba]–[wa], differing from one another in the duration and rate of the first three formant transitions. A significant effect was obtained after repetitively uttering a sequence of [wa]–[ya] syllables but not after uttering a sequence of [ba]–[da]. In Experiment III, a category judgement response was required for the [ba]–[wa] stimuli, using the integers 1 through 7. A signal detectability analysis was applied to the results of this experiment and showed a significant perceptuo-motor effect after uttering a sequence of [ba]–[da] but not [wa]–[ya]. Finally, the category judgement task was used in Experiment IV with another series of syllables, [ba]–[pha], which differed from one another in voice-onset time. No significant effects of perceptuo-motor adaptation were obtained with the [ba]–[pha] series, and their absence was attributed to the absence of voice-onset time as a cue for distinguishing such syllables in whispered speech. The perceptuo-motor results are compared with the results obtained with a strictly perceptual adaptation paradigm.
Treatment at Academic Centers Increases Likelihood of Reconstruction After Mastectomy for Breast Cancer Patients

BACKGROUND Mastectomy rates continue to increase in women diagnosed with breast cancer (BC). There are limited data regarding reconstruction rates at academic centers (AC) versus community hospitals (CH). We aim to determine the effect of facility type on reconstruction rates. MATERIALS AND METHODS The National Cancer Database was queried for BC patients treated with mastectomy from 2004 to 2014. Clinical characteristics and type of reconstruction were compared between treatment at AC or CH. RESULTS A total of 860,509 patients were included. Patients treated at AC were younger (58.7 ± 12 y AC versus 61.6 ± 13 y CH; P < 0.001) and traveled farther to their treatment center (33.1 ± 122.8 miles AC versus 20 ± 75.3 miles CH; P < 0.001). Patients undergoing surgery at AC were more likely to have reconstruction than those at CH (43.7% AC versus 32.5% CH; P < 0.001). This trend remained across all reconstruction types including expander/implant-based reconstruction (immediate breast reconstruction) (14.4% AC versus 9.9% CH), autologous reconstruction (14.9% AC versus 11.7% CH), mixed reconstruction (5.2% AC versus 3.6% CH), and other reconstructions (9.2% AC versus 7.3% CH) (all P < 0.001). Patients in all age categories, across insurance statuses, and with comorbidities were more likely to receive reconstruction if treated at AC compared with CH. In multivariate analysis, having a mastectomy at AC was an independent predictor of reconstruction (adjusted odds ratio, 1.51; 95% confidence interval, 1.49-1.51; P < 0.001). CONCLUSIONS Undergoing mastectomy at AC results in higher rate of reconstruction compared with CH.
Mixed reality as a time-efficient alternative to cadaveric dissection

Objectives: The extent of medical knowledge increases yearly, but the time available for students to learn is limited, leading to administrative pressures to revise and reconfigure medical school c...
Pityriasis versicolor in children: a retrospective study of 483 cases

Objective To assess the clinical characteristics of pityriasis versicolor (PV) in children vs adults. Methods Questionnaire was designed and given to consecutive patients with PV in the Department of Dermatology, Wuxi Children's Hospital, for collection of information on their sex, age, onset age, duration of disease, localization of lesions, inducement, onset season, and family history. Findings on mycological examination before and after medication were assessed. Results Totally, 483 children with PV were enrolled, including 286 (59.2%) boys and 197 (40.8%) girls. Patients aged from 15 days to 12 years. Facial lesions were the most frequent (n = 207, 42.9% ) manifestation with a preference on the forehead (n = 143, 69.1% ). Hyperhidrosis was found in 405 (83.9%) patients, and family history of PV in 38 (7.9%) patients. Patients were instructed to apply bifonazole 1% cream on lesions. After more than 2 weeks of treatment, 447 (92.5%) patients obtained both clinical and mycological improvement. Conclusions Difference is present between pediatric and adult PV in clinical manifestations and pathogenic factors. Furthermore, PV should be differentially diagnosed from other hypopigmented skin conditions on the face in children. Key words: Tinea, versicolor; Child; Retrospective studies
A Randomized Study to Assess the Effect of Including the Graduate Record Examinations Results on Reviewer Scores for Underrepresented Minorities.

Whether requiring Graduate Record Examinations (GRE) results for doctoral applicants affects the diversity of admitted cohorts remains uncertain. This study randomized applications to 2 population-health doctoral programs at the University of California San Francisco to assess whether masking reviewers to applicant GRE results differentially affects reviewers' scores for underrepresented minority (URM) applicants from 2018-2020. Applications with GRE results and those without were randomly assigned to reviewers to designate scores for each copy (1-10, 1 being best). URM was defined as self-identification as African American/Black, Filipino, Hmong, Vietnamese, Hispanic/Latinx, Native American/Alaska Native, or Native Hawaiian/Other Pacific Islander. We used linear mixed models with random effects for the applicant and fixed effects for each reviewer to evaluate the effect of masking the GRE results on the overall application score and whether this effect differed by URM status. Reviewer scores did not significantly differ for unmasked versus masked applications among non-URM applicants (β = 0.15; 95% CI: -0.03, 0.33) or URM applicants (β = 0.02, 95% CI: -0.49, 0.54). We did not find evidence that removing GREs differentially affected URM compared with non-URM students (β for interaction = -0.13, 95% CI: -0.55, 0.29). Within these doctoral programs, results indicate that GRE scores neither harm nor help URM applicants.
Shining more light on RAS inhibition during the COVID-19 pandemic

The coronavirus disease 2019 (COVID-19) pandemic has resulted in unprecedented challenges throughout the nephrology community. Notably, it was quickly realized that the virus responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), uses the angiotensin-converting
An experimental and analytical investigation of isolated rotor flap-lag stability in forward flight

The flap-lag stability of an isolated hingeless rotor is investigated, both experimentally and analytically, in hover and in forward flight. The effects of forward flight aerodynamics on regressing lead-lag mode stability are the focus of the investigation. The soft-inplane, three-bladed, isolated model rotor was operated untrimmed at advance ratios from hover to 0.55 and at shaft angles as high as 20 deg. The experimental data base includes forward flight damping data for two lead-lag natural frequencies, for three values of collective pitch, and for both zero and full-lag structural coupling. With the aid of computerized symbolic manipulation, a rigid-blade lag-flap model analysis was developed to calculate the Floquent eigenvalues and to identify the modes. Good correlation is shown for some cases, but other cases show large discrepancies between the theory and experiment.
Cultural and Spatial Perceptions of Miami’s Little Havana

Miami’s ‘Little Havana’ is known by many for its famous Southwest 8 th Street, the Calle Ocho festival , and for the many Latin people, particularly Cubans, that live in the area . However, the current name of the neighborhood hides all of the dynamics of neighborhood change and creates the notion that Little Havana is a static monoculture. This study measured people’s perception of Little Havana by surveying 153 residents to identify the cultural associations and to capture the participant’s spatial perceptions of Little Havana. This study found that survey participants from inside the study area associated Little Havana more with Cuban culture and had more positive things to say about the neighborhood. Finally, this study suggests that the core of Little Havana was encompassed by West Flagler Street on the north, Southwest 8 th Street on the south, Southwest 27 th Avenue on the west, and Southwest 4 th Avenue on the east.
Price discrimination and bargaining power in the U.S. vaccine market

Abstract The U.S. vaccine market exhibits a pricing structure in which the major purchaser of vaccines, the public sector, receives substantial discounts. This outcome is consistent with three theories of market behavior: third-degree price discrimination; bargaining power; and cost differences. The true nature of this pricing structure has important efficiency and policy implications. This paper uses a longitudinal data set of private catalog and federal contract prices to empirically determine whether price discrimination or bargaining power is being practiced in this market. I find that, while it is not possible to eliminate other factors, the results favor the bargaining power hypothesis.
Diabetes mellitus and the central nervous system.

Publisher Summary Diabetes mellitus (DM) disturbs central nervous system (CNS) function and may injure the brain. An emerging body of literature has shown that there are manifold biological effects of diabetes on the brain. Insulin action on the brain influences neurotransmission. Diabetes increases the risk of stroke and exacerbates stroke damage and mortality. Stroke damage is worsened potentially both through the effects of hyperglycemia and lack of insulin upon brain biochemistry in the presence of ischemia. The major treatment side effect of diabetes, which is hypoglycemia, may acutely impair brain function and, when severe and prolonged, may permanently injure the brain largely through excitotoxic mechanisms or cause death. The physiological adaptations of blood-brain barrier (BBB) function, brain metabolism, cerebral blood flow, and microvascular function may occur with either hyper- or hypoglycemia. Future research directions should delineate new areas and mechanisms of abnormalities in brain function in diabetes. Future research should also explore the basis for CNS functional alterations in acute and chronic hyper- and hypoglycemia. It would be desirable to initiate clinical trials to limit the adverse CNS effects of diabetes on stroke. A better understanding of how hyper- and hypoglycemia impair brain function may help spare the brain from the harm of altered metabolism in diabetes. This chapter focuses on clinically relevant pathophysiology. It deals with the studies that relate altered insulin and glucose concentrations to both short- and long-term adverse consequences to the brain.
Redistribution and Retention of Soil Moisture

The redistribution is a downward movement of water in the absence of groundwater, or where the water table is too deep to affect the relevant depth zone. Its effect is to redistribute water in the soil by increasing the wetness of successively deeper layers at the expense of the infiltration-wetted upper layers of the profile. There is a great importance of the redistribution process because it determines the amount of water retained at various times by the different depth zones in the soil profile and hence affects the water economy of plants. The rate and duration of downward flow during redistribution determine the effective soil-water storage. This property is vitally important, particularly in relatively dry regions, where water supply is infrequent and plants rely for long periods on the unreplenished reservoir of water within the rooting zone. Even in relatively humid regions, where the water supply by precipitation seems to be sufficient, inadequate soil-moisture storage may deprive growing plants of a major portion of the water supply and can cause crop failure. Therefore, the redistribution process is important because it often determines the amount of water that flows through the root zone and hence the extent of leaching of solutes and recharge of groundwater that takes place. The soil-water storage is generally not a fixed quantity or static property but a dynamic process.
Treatment of Tobacco Dependence in Alcoholics

Because of the high morbidity and mortality that alcoholic smokers experience from tobacco-caused diseases, treatment for tobacco dependence among alcoholics is warranted. Much progress has been made during the last decade in addressing tobacco dependence in alcoholism treatment units. Treatment of tobacco dependence in alcoholic smokers does not seem to cause excessive relapse to drinking and, in fact, stopping smoking may enhance abstinence from drinking. Therefore, treatment for alcoholic smokers should take place whenever and wherever the patient comes in contact with the health care system. Because alcoholic smokers as a rule are more dependent on nicotine than their nonalcoholic counterparts, they may need more intensive pharmacotherapy and behavioral therapy. Because many of them have experienced 12-step approaches to recovery, that same technology can be used to initiate and maintain abstinence from tobacco use. Moreover, several pharmacologic options exist to treat tobacco dependence in alcoholic smokers. However, the efficacy of several pharmacologic therapies for alcoholic smokers needs to be tested. In addition, further research is needed on effective treatments for recovering alcoholics of various racial/ethnic backgrounds.
High frequency ferroresonant modeling and performance

A mathematical model for ferroresonant circuit operation is reviewed that addresses some of the deficiencies of earlier analyses. The model gives results that compare well with experimental data and can be used to design ferroresonant regulators at any frequency. The design and operation of a high-frequency ferroresonant power supply is discussed. >
On-label and off-label use of high-dose influenza vaccine in the United States, 2010-2012

High-dose inactivated, influenza vaccine was licensed by the FDA in December 2009 for adults aged 65 y and older. The ACIP did not issue or state a preference for a specific vaccine in the elderly population. The extent of its on-label and off-label use is unknown. Using the MarketScan Commercial Claims and Encounters and the Medicare Supplemental database, we identified individuals who received the high-dose influenza vaccine or the standard, seasonal trivalent influenza vaccine between January 1, 2010 and December 31, 2012. For people aged ≥65 y, we used multivariable regression to assess the association between patient and provider level variables and high-dose influenza vaccine versus standard influenza vaccine. We characterized all off-label high-dose vaccine administered to people younger than 65 y of age, and investigated whether sicker patients were targeted for off-label use by examining the association between various comorbid conditions and receipt of the high-dose vaccine among adults aged 18-64. Among patients aged ≥65 y who received an influenza vaccine, 18.4% received the high-dose vaccine. Uptake was minimal in 2010, but 25% and 32% of influenza shots were the high-dose formulation in 2011 and 2012, respectively. Almost 27,000 seniors received a second high-dose vaccine with a median of 368 d (IQR: 350-387 days) between doses. Older age, family practice physicians, and having PPO insurance were positively associated with receiving high-dose vaccine. There were 36,624 off-label high-dose vaccines administered. Half of the patients receiving off-label doses were aged 50-64. Adults aged 18-64 y receiving high-dose vaccine were more likely to have chronic comorbidities than people receiving standard influenza vaccine; however, there was not one specific illness that seemed to be targeted by physicians. In the first 3 y since licensure, use of the high-dose vaccine among seniors has been limited. The safety of this vaccine should be monitored closely among 2 groups of people - seniors receiving repeat doses and people <65.
Differential phenotypic characteristics of heterogeneous cell population in the rabbit periosteum

Background Periosteum and periosteum-derived progenitor cells have demonstrated the potential for stimulative applications in repair of various musculoskeletal tissues. It has been found that the periosteum contains mesenchymal progenitor cells that are capable of differentiating into either osteoblasts or chondrocytes, depending on the culture conditions. Anatomically, the periosteum is a heterogeneous multilayered membrane, consisting of an outer fibrous and an inner cambium layer. The present study was designed to elucidate the phenotypic characteristics of fibrous and cambium layer cells in vitro.Methods Using a sequential enzymatic digestion method, fibrous and cambium layer cells were harvested separately from periosteum-bone explants of the proximal tibia of 6-month-old New Zealand White rabbits.Results We found that the cells from each layer showed distinct phenotypic characteristics in a primary monolayer culture system. Specifically, the cambium cells demonstrated higher osteogenic characteristi...
Size-dependent two-photon excitation spectroscopy of CdSe nanocrystals.

Two-photon excitation spectra of highly monodisperse colloidal CdSe nanocrystals with sizes ranging from 22 to 43 \AA{} are compared to one-photon excitation data and to a spherically confined effective-mass model. The main experimental features are well described by this model. However, the first one-photon and two-photon transitions appear indistinguishable, though the model predicts a 20-meV splitting. This discrepancy may reflect the sensitivity of the band-edge structure to deviations from the assumed spherical symmetry. \textcopyright{} 1996 The American Physical Society.
Identification of a new modulator of the intercalated disc in a zebrafish model of arrhythmogenic cardiomyopathy.

Arrhythmogenic cardiomyopathy (ACM) is characterized by frequent cardiac arrhythmias. To elucidate the underlying mechanisms and discover potential chemical modifiers, we created a zebrafish model of ACM with cardiac myocyte–specific expression of the human 2057del2 mutation in the gene encoding plakoglobin. A high-throughput screen identified SB216763 as a suppressor of the disease phenotype. Early SB216763 therapy prevented heart failure and reduced mortality in the fish model. Zebrafish ventricular myocytes that expressed 2057del2 plakoglobin exhibited 70 to 80% reductions in INa and IK1 current densities, which were normalized by SB216763. Neonatal rat ventricular myocytes that expressed 2057del2 plakoglobin recapitulated pathobiological features seen in patients with ACM, all of which were reversed or prevented by SB216763. The reverse remodeling observed with SB216763 involved marked subcellular redistribution of plakoglobin, connexin 43, and Nav1.5, but without changes in their total cellular content, implicating a defect in protein trafficking to intercalated discs. In further support of this mechanism, we observed SB216763-reversible, abnormal subcellular distribution of SAP97 (a protein known to mediate forward trafficking of Nav1.5 and Kir2.1) in rat cardiac myocytes expressing 2057del2 plakoglobin and in cardiac myocytes derived from induced pluripotent stem cells from two ACM probands with plakophilin-2 mutations. These observations pinpoint aberrant trafficking of intercalated disc proteins as a central mechanism in ACM myocyte injury and electrical abnormalities.
Mixed parallel-perpendicular morphologies in diblock copolymer systems correlated to the linear viscoelastic properties of the parallel and perpendicular morphologies

Large-amplitude oscillatory shear (LAOS) has been applied to a lamellar, microphase-separated, low molecular weight poly(styrene-b-isoprene) diblock copolymer melt to induce macroscopically aligned morphologies. Small-angle X-ray scattering and dynamic mechanical testing were performed to characterize the states of orientation. The perpendicular orientation was induced by applying LAOS at a fixed frequency (1 rad/s) and strain amplitude (100%) at high temperatures. LAOS applied at the same frequency and strain amplitude but at lower temperatures induced the parallel orientation. Interestingly, intermediate temperatures produced a mixed morphology containing both parallel and perpendicular orientations. The linear viscoelastic responses of the parallel and perpendicular morphologies were related to the LAOS conditions necessary to produce the perpendicular, the parallel, and the mixed parallel−perpendicular morphologies. Specifically, two frequencies were defined using the linear viscoelastic responses: ω...
The vaporization enthalpies and vapor pressures of fatty acid methyl esters C18, C21 to C23, and C25 to C29 by correlation – gas chromatography

Abstract Vapor pressures and vaporization enthalpies for methyl heptadecanoate and methyl heneicosanoate to methyl octacosanoate exclusive of methyl tricosanoate are evaluated as a function of temperature over the temperature range T = 298.15–450 K by correlation gas chromatography. The results are generated by an extrapolative process using literature values for methyl tetradecanoate to methyl eicosanoate as standards. Relationships for calculating vapor pressures of the title compounds from T = 298.15 to 450 K are provided. Experimental fusion enthalpies are also reported for the methyl esters from methyl hexadecanoate to methyl octacosanoate excluding methyl tridecanoate. Vaporization enthalpies and fusion enthalpies adjusted for temperature to T = 298.15 K are combined to provide sublimation enthalpies. The results are compared to available literature values. A rationale for the linear relationship observed between enthalpies of vaporization and enthalpies of transfer from solution to the vapor is also provided.
A bandwidth sharing approach to improve licensed spectrum utilization

The spectrum of deployed wireless cellular communication systems is found to be underutilized, even though licensed spectrum is at a premium. To efficiently utilize the bandwidth left unused in a cellular system, the primary system (PRI), we propose an overlaid ad hoc secondary network (ASN) architecture, with the ASN operating over the resources left unutilized by the PRI. Our basic design principle is that the ASN operates in a nonintrusive manner and does not interact with the PRI. In this article we present the ad hoc secondary medium access control (AS-MAC) protocol to enable PRI-SEC interoperation, address a number of technical challenges pertinent to this networking environment, and evaluate the performance of the AS-MAC. In a single-hop ASN the AS-MAC transparently utilizes 75 percent of the bandwidth left unused by the PRI, while in multihop ASNs, due to spatial reuse, the AS-MAC can utilize up to 132 percent of the idle PRI resources in our experiments.
Cytoplasmic synthesis of RNA in the sea urchin embryo

Summary Autoradiographic and biochemical studies on enucleate halves of sea urchin eggs ( Arbacia punctulata ) show that RNA synthesis can take place in the cytoplasm. The products transcribed in activated enucleate fragments are heterodisperse in sedimentation and of high molecular weight. After a 2-hour period of labeling, the new RNA molecules are distributed throughout the cytoplasm, as determined by autoradiographic detection of their radioactivity. No class of organelles or particles is strongly labeled. The transcription of cytoplasmic templates may be somewhat more resistant to actinomycin treatment than is RNA synthesis of the embryo or fertilized nucleate half-egg. No conclusions are possible in respect to relative rates of cytoplasmic and nuclear transcription during early development, but these results support the possibility of an important cytoplasmic contribution during early cleavage.
Exocytosis of cytolytic granules may not be required for target cell lysis by cytotoxic T-lymphocytes.

Secretory processes have been implicated in the mechanism of target-cell lysis by cytotoxic T-lymphocytes (CTL) (refs 1,2). Both CTL and cytotoxic large granular lymphocytes have cytolytic granules3,4, containing the cytolytic molecules 'perforin'3 and 'cytolysin'4; perforin and cytotoxic lymphocytes can damage target cells through the membrane assembly of pores3–5. The description of proteases which are cytotoxic cell-associated and granule-located has supported the granule exocytosis model of cytotoxicity mediated by cytotoxic lymphocytes, and has emphasized the similarities between cell-mediated and complement-mediated cytotoxicity6–14. But recent experiments have15 challenged the importance of lytic granules and perforin in CTL ac15,16. Here we report that CTL can be triggered to deliver a lethal hit to target cells even when exocytosis of lytic granules has been abolished by removal of extracellular calcium. This dissociation of exocytosis of granules and delivery of the lethal hit suggests that cytolytic granules may not be involed in target-cell lysis by CTL.
Effect of Mycoplasma dispar, Mycoplasma bovirhinis, Acholeplasma laidlawii and T-mycoplasmas on explant cultures of bovine trachea.

Abstract Mycoplasma growth curves, ciliary motility and histopathology have been studied in bovine foetal tracheal explant cultures inoculated with M. dispar , M. bovirhinis , A. laidlawii and T-mycoplasmas. All mycoplasmas studied established and multiplied in the explant cultures, but only M. dispar produced cytopathic effects on the ciliated epithelial cells, causing progressive sloughing of cells and patchy flattening of the epithelial layer over 6 days. The cytopathic effect was associated with the presence of large numbers of mycoplasmas. T-mycoplasmas isolated from the bovine urogenital tract, the bovine eye and pneumonic calf lungs had no cytopathic effect and there was no correlation between the ability to grow in tracheal tissue and virulence as assayed in the bovine mammary gland.
Managing the information revolution: library management, the control of prescriptive technologies, and the future of librarianship

This article seeks to promote a critical perspective on the present conceptualization of library management and the problems posed by technology. More specifically, it addresses the challenges faced by library administrators in relation to computing technologies. Through the adoption of Ursula Franklin's view of technology as “practice”, the article contrasts the practice of holistic and prescriptive technologies in library contexts. It also addresses the transformations of librarianship and the increasing adoption of prescriptive technological models. To exemplify the ongoing destruction of traditional librarianship, the three practices that comprise the fundamentals of librarianship are analyzed, namely, cataloging, collection development, and reference work.
Liability of the sleep-deprived resident.

Medical Legal Issues Clearly, a hospital or medical center that pays the salary of residents assumes the legal liability for negligent conduct committed by those residents if the conduct is related to the residents’ duties [3]. However, a hospital is not liable for negligent conduct committed by employed residents if that conduct is not related to the duties of the resident while working outside the hospital [4]. The issue presented in the lawsuit discussed here is unique, however, because the alleged act of negligence did not fall neatly into either one of these scenarios. Although at the time she caused the automobile accident the resident was neither on duty nor carrying out duties required by the residency, she was admittedly physically and mentally impaired because of work requirements that were imposed by the hospital when she had been on duty. The Illinois Appeals Court declined to hold the medical center liable or impose on it a legal duty to avoid injury to a third party even though the medical center was apparently responsible for the resident’s sleepdeprived condition when she caused the accident. Appeals courts in other states, however, have ruled differently on this issue. Although not specifically dealing with health care entities or patients, the legal issue presented in the following four cases—whether a business or other entity that has imposed on its employees working conditions that can cause the employees to remain physically or mentally impaired after going off duty, which in turn causes an injury to a third-party individual, can be held liable for that third party’s injury—was very similar to that ruled on by Liability of the Sleep-Deprived Resident
Do septal neurons pace the hippocampal theta rhythm

The hippocampal theta rhythm (rhythmical slow activity, RSA) is one of the most thoroughly studied EEG phenomena. Much of this experimental interest has been stimulated by suggestions that the mnemonic functions of the hippocampus may depend upon theta-related neuronal activity. Inputs from the medial septal nuclei to the hippocampus were shown to be essential for the theta rhythm in the 1950s, but the role of these basal forebrain projections has not been clearly defined. Four models of the septo-hippocampal connections involved in theta rhythm production are reviewed as the precise roles of these projections are discussed. In our final, consolidated model both cholinergic and GABAergic septal projection cells fire in rhythmic bursts that entrain hippocampal interneurons. The resulting rhythmic inhibition of hippocampal projection cells, together with their excitatory interconnections, generates at least one component of the theta rhythm.
Disease lesion mimics of maize: A model for cell death in plants

A class of maize mutants, collectively known as disease lesion mimics, display discrete disease-like symptoms in the absence of pathogens. It is intriguing that a majority of these lesion mimics behave as dominant gain-of-function mutations. The production of lesions is strongly influenced by light, temperature, developmental state and genetic background. Presently, the biological significance of this lesion mimicry is not clear, although suggestions have been made that they may represent defects in the plants' recognition of, or response to, pathogens. One feature that is common to all lesion mimics is their association with cell death. In plants, as in animals, a number of developmental and pathological processes exist where controlled cell death, whether programmed or triggered in response to physiological or environmental stimuli, constitutes the normal aspect of life. Might disease lesion mimic mutations represent variants where regulation of desirable cell death has gone awry? In this paper we argue that this might be the case, and further conjecture that these mutants offer a unique opportunity for studying the genetic and cellular mechanisms of cell death in plants.
Purifying salmon oil using adsorption, neutralization, and a combined neutralization and adsorption process.

Abstract The performance of activated earth and/or chitosan as an adsorbent to remove free fatty acids (FFA) and peroxides from the unpurified salmon oil was evaluated. The unpurified salmon oil was purified using three methods included activated earth adsorption process, neutralization process, and combined neutralization and activated earth adsorption processes. The purified salmon oil samples were evaluated for free fatty acids (FFA), peroxide values (PV), minerals, color, tocopherols, moisture content, insoluble impurities, and water activity. Neither chitosan nor the activated earth adsorption process was effective in removing FFA from the salmon oil. Neutralized oil had a higher intraparticular diffusion coefficient than the unpurified salmon oil for adsorbing peroxides. FFA of unpurified salmon oil was 3.5% and was significantly reduced (P
A paradigm shift in GP-GPU computing: task based execution of applications with dynamic data dependencies

General purpose computing on GPUs have became increasingly popular over the last decade. Scientific applications with SIMD computation characteristics show considerable performance improvements when run on these massively parallel architectures. However, data dependencies across thread blocks significantly impact the degree of achievable parallelism by requiring global synchronization across multi-processors (SMs) inside the GPU.In order to efficiently run applications with inter-block data dependencies, we need fine-granular `task-based execution models' that will treat SMs inside GPU as stand-alone parallel processing units. Such a scheme will enable efficient execution by utilizing all internal computation elements inside GPU and eliminating unnecessary waits during global barriers.In this paper, we propose a new, dynamic and `all-in-GPU' task execution framework for executing both regular and irregular data-dependent applications on GPUs. Our run-time eliminates the need for global synchronization and minimize inter-SM communication through distributed queues. In our preliminary experiments run on a Tesla c2050 GPU, we have obtained up to 62% more speedup when compared to centralized queue approach. The overhead of system has been measured as low as 5%.
A Phase I clinical and pharmacology study using amifostine as a radioprotector in dose-escalated whole liver radiation therapy

Purpose Diffuse intrahepatic tumors are difficult to control. Whole-liver radiotherapy has been limited by toxicity, most notably radiation-induced liver disease. Amifostine is a prodrug free-radical scavenger that selectively protects normal tissues and, in a preclinical model of intrahepatic cancer, systemic amifostine reduced normal liver radiation damage without compromising tumor effect. We hypothesized that amifostine would permit escalation of whole-liver radiation dose to potentially control microscopic disease. We also aimed to characterize the pharmacokinetics of amifostine and its active metabolite WR-1065 to optimize timing of radiotherapy. Methods and Materials We conducted a radiation dose-escalation trial for patients with diffuse, intrahepatic cancer treated with whole-liver radiation and intravenous amifostine. Radiation dose was assigned using the time-to-event continual reassessment method. A companion pharmacokinetic study was performed. Results Twenty-three patients were treated, with a maximum dose of 40 Gy. Using a logistical regression model, compared with our previously treated patients, amifostine increased liver tolerance by 3.3 ± 1.1 Gy ( p = 0.007) (approximately 10%) with similar response rates. Peak concentrations of WR-1065 were 25 μM with an elimination half-life of 1.5 h; these levels are consistent with radioprotective effects of amifostine in patients. Conclusion These findings demonstrate for the first time that amifostine is a normal liver radioprotector. They further suggest that it may be useful to combine amifostine with fractionated or stereotactic body radiation therapy for patients with focal intrahepatic cancer.