1,194 research outputs found

    Recent Developments in Osteogenesis Imperfecta

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    Osteogenesis imperfecta (OI) is an uncommon genetic bone disease associated with brittle bones and fractures in children and adults. Although OI is most commonly associated with mutations of the genes for type I collagen, many other genes (some associated with type I collagen processing) have now been identified. The genetics of OI and advances in our understanding of the biomechanical properties of OI bone are reviewed in this article. Treatment includes physiotherapy, fall prevention, and sometimes orthopedic procedures. In this brief review, we will also discuss current understanding of pharmacologic therapies for treatment of OI

    A mechanical, thermal and electrical packaging design for a prototype power management and control system for the 30 cm mercury ion thruster

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    A prototype electric power management and thruster control system for a 30 cm ion thruster is described. The system meets all of the requirements necessary to operate a thruster in a fully automatic mode. Power input to the system can vary over a full two to one dynamic range (200 to 400 V) for the solar array or other power source. The power management and control system is designed to protect the thruster, the flight system and itself from arcs and is fully compatible with standard spacecraft electronics. The system is easily integrated into flight systems which can operate over a thermal environment ranging from 0.3 to 5 AU. The complete power management and control system measures 45.7 cm (18 in.) x 15.2 cm (6 in.) x 114.8 cm (45.2 in.) and weighs 36.2 kg (79.7 lb). At full power the overall efficiency of the system is estimated to be 87.4 percent. Three systems are currently being built and a full schedule of environmental and electrical testing is planned

    The Plasma Interaction Experiment (PIX) description and test program

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    The plasma interaction experiment (PIX) is a battery powered preprogrammed auxiliary payload on the LANDSAT-C launch. This experiment is part of a larger program to investigate space plasma interactions with spacecraft surfaces and components. The varying plasma densities encountered during available telemetry coverage periods are deemed sufficient to determine first order interactions between the space plasma environment and the biased experimental surfaces. The specific objectives of the PIX flight experiment are to measure the plasma coupling current and the negative voltage breakdown characteristics of a solar array segment and a gold plated steel disk. Measurements will be made over a range of surface voltages up to plus or minus kilovolt. The orbital environment will provide a range of plasma densities. The experimental surfaces will be voltage biased in a preprogrammed step sequence to optimize the data returned for each plasma region and for the available telemetry coverage

    Workplace Giving in Universities: A U.S. Case Study at Indiana University

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    The phenomenon of workplace giving is underexamined in the scholarly literature; philanthropic gifts by employees to their nonprofit employers have received less attention within national and transnational contexts. This study considered the association between university staff propensity toward “internal workplace giving” and donor characteristics, drawing on literature about organizational commitment and identification as a beginning for advancing theoretical understanding of employee–employer relationships and giving at both the micro-level and meso-level. The sample of 17,038 employees covered 3 years at Indiana University, an American, public, multicampus institution. Despite its specific national and cultural context, the study raises relevant issues about workplace giving. Relational and personal characteristics were found to be significant predictors for determining who donates; using these characteristics to predict giving levels, however, was less successful. The study anticipates a growing need for related research and provides direction for further methodological and theoretical approaches

    Parabrachial opioidergic projections to preoptic hypothalamus mediate behavioral and physiological thermal defenses

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    Maintaining stable body temperature through environmental thermal stressors requires detection of temperature changes, relay of information, and coordination of physiological and behavioral responses. Studies have implicated areas in the preoptic area of the hypothalamus (POA) and the parabrachial nucleus (PBN) as nodes in the thermosensory neural circuitry and indicate that the opioid system within the POA is vital in regulating body temperature. In the present study we identify neurons projecting to the POA from PBN expressing the opioid peptides dynorphin and enkephalin. Using mouse models, we determine that warm-activated PBN neuronal populations overlap with both prodynorphin (Pdyn) and proenkephalin (Penk) expressing PBN populations. Here we report that in the PB

    Longtime behavior of nonlocal Cahn-Hilliard equations

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    Here we consider the nonlocal Cahn-Hilliard equation with constant mobility in a bounded domain. We prove that the associated dynamical system has an exponential attractor, provided that the potential is regular. In order to do that a crucial step is showing the eventual boundedness of the order parameter uniformly with respect to the initial datum. This is obtained through an Alikakos-Moser type argument. We establish a similar result for the viscous nonlocal Cahn-Hilliard equation with singular (e.g., logarithmic) potential. In this case the validity of the so-called separation property is crucial. We also discuss the convergence of a solution to a single stationary state. The separation property in the nonviscous case is known to hold when the mobility degenerates at the pure phases in a proper way and the potential is of logarithmic type. Thus, the existence of an exponential attractor can be proven in this case as well

    ECOG-ACRIN (E4805) Randomized Phase II Study to Determine the Effect of 2 Different Doses of Aflibercept in Patients with Metastatic Renal Cell Carcinoma

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    Background—Aflibercept is a recombinantly-produced fusion protein that has potent anti-VEGF activity. We tested whether aflibercept has clinical activity in clear cell renal cell carcinoma (ccRCC). The recommended Phase 2 dose was 4 mg/kg but several patients treated at 1 mg/kg demonstrated prolonged progression-free survival (PFS). We therefore tested both doses in a parallel group randomized trial. Methods—Eligible patients (pts) had histologically confirmed advanced or metastatic ccRCC and previous treatments including prior exposure to a VEGF RTKI. Patients received aflibercept (either 1 mg/kg or 4 mg/kg) day 1 of a 14-day cycle until progression. Patients randomized to 1 mg/kg could crossover to 4 mg/kg at progression. The primary endpoint was proportion alive and progression-free at 8 weeks. A Simon 2-stage design was used for each arm with 33 and 24 eligible pts/arm enrolled in stages 1 and 2. Results—94 pts were enrolled, 59 and 35 to 4 mg and 1 mg doses, respectively. 72% had 1 prior tx most commonly sunitinib. 16 eligible pts crossed over at progression to the 4 mg dose. Most common adverse events were hypertension, proteinuria, and fatigue. Only 4 pts reported Grade 4 or higher toxicity. With 36/59 (61%) pts PFS at 8 wks, the 4-mg/kg dose met protocol specified efficacy criteria. Conclusions—Aflibercept is active in previously treated ccRCC and may be worthy of further study

    Effect of superparamagnetic iron oxide nanoparticles on glucose homeostasis on type 2 diabetes experimental model

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    [Aims]: Evaluation of the anti-diabetic effect of superparamagnetic iron oxide nanoparticles (SPIONs) on Type 2 diabetic rats and compared their effect to metformin treatment.[Main methods]: Diabetic rats were treated with different doses of nanoparticles one time per week for 4 weeks. Fasting blood glucose level was determined for studied groups during the experimental period (30 days). At the end of the experiment, oral glucose tolerance test was carried out, serum samples were collected for biochemical assays. Then animals were sacrificed to obtain tissues for assessment of glucose transporters, insulin receptors and insulin signaling proteins.[Key finding]: SPIONs treatment normalized fasting blood glucose and lowering insulin level in diabetic rats compared to untreated diabetic rats. SPIONs significantly ameliorate the glucose sensing and the active components of insulin signaling pathway. The anti-diabetic effects of SPIONs may be mediated through its effect on (i) hepatic peroxisome proliferator-activated receptor gamma coactivator 1-alpha content, which induced by SPIONs treatment in a dose-dependent manner, (ii) adipocytokines as SPIONs treated diabetic rats showed significantly higher levels of adiponectin and lower retinol binding protein 4 compared to untreated diabetic rats, (iii) lipid profile as SPIONs treatment significantly corrected the lipid profile in a dose-dependent manner and to a similar extent as metformin or even better.[Significance]: To our knowledge, this is the first study that explores the anti-diabetic effects of SPIONs on diabetic model.This work was partially supported by the Spanish Ministry of Science, Innovation and Universities (Grant PGC2018-095795-B-I00) and by the European Union's Horizon 2020 FET Open Programme (Grant no. 801305).Peer reviewe

    Quality of Service Provisioning for Heterogeneous Services in Cognitive Radio-enabled Internet of Things

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    IEEE The Internet of Things (IoT) is a network of interconnected objects, in which every object in the world seeks to communicate and exchange information actively. This exponential growth of interconnected objects increases the demand for wireless spectrum. However, providing wireless channel access to every communicating object while ensuring its guaranteed quality of service (QoS) requirements is challenging and has not yet been explored, especially for IoT-enabled mission-critical applications and services. Meanwhile, Cognitive Radio-enabled Internet of Things (CR-IoT) is an emerging field that is considered the future of IoT. The combination of CR technology and IoT can better handle the increasing demands of various applications such as manufacturing, logistics, retail, environment, public safety, healthcare, food, and drugs. However, due to the limited and dynamic resource availability, CR-IoT cannot accommodate all types of users. In this paper, we first examine the availability of a licensed channel on the basis of its primary users' activities (e.g., traffic patterns). Second, we propose a priority-based secondary user (SU) call admission and channel allocation scheme, which is further based on a priority-based dynamic channel reservation scheme. The objective of our study is to reduce the blocking probability of higher-priority SU calls while maintaining a sufficient level of channel utilization. The arrival rates of SU calls of all priority classes are estimated using a Markov chain model, and further channels for each priority class are reserved based on this analysis. We compare the performance of the proposed scheme with the greedy non-priority and fair proportion schemes in terms of the SU call-blocking probability, SU call-dropping probability, channel utilization, and throughput. Numerical results show that the proposed priority scheme outperforms the greedy non-priority and fair proportion schemes
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