685 research outputs found

    Surface Engineering Strategy Using Urea To Improve the Rate Performance of Na2Ti3O7 in Na‐Ion Batteries

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    Na2Ti3O7 (NTO) is considered a promising anode material for Na‐ion batteries due to its layered structure with an open framework and low and safe average operating voltage of 0.3β€…V vs. Na+/Na. However, its poor electronic conductivity needs to be addressed to make this material attractive for practical applications among other anode choices. Here, we report a safe, controllable and affordable method using urea that significantly improves the rate performance of NTO by producing surface defects such as oxygen vacancies and hydroxyl groups, and the secondary phase Na2Ti6O13. The enhanced electrochemical performance agrees with the higher Na+ ion diffusion coefficient, higher charge carrier density and reduced bandgap observed in these samples, without the need of nanosizing and/or complex synthetic strategies. A comprehensive study using a combination of diffraction, microscopic, spectroscopic and electrochemical techniques supported by computational studies based on DFT calculations, was carried out to understand the effects of this treatment on the surface, chemistry and electronic and charge storage properties of NTO. This study underscores the benefits of using urea as a strategy for enhancing the charge storage properties of NTO and thus, unfolding the potential of this material in practical energy storage applications

    Muscle size explains low passive skeletal muscle force in heart failure patients.

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    BACKGROUND: Alterations in skeletal muscle function and architecture have been linked to the compromised exercise capacity characterizing chronic heart failure (CHF). However, how passive skeletal muscle force is affected in CHF is not clear. Understanding passive force characteristics in CHF can help further elucidate the extent to which altered contractile properties and/or architecture might affect muscle and locomotor function. Therefore, the aim of this study was to investigate passive force in a single muscle for which non-invasive measures of muscle size and estimates of fiber force are possible, the soleus (SOL), both in CHF patients and age- and physical activity-matched control participants. METHODS: Passive SOL muscle force and size were obtained by means of a novel approach combining experimental data (dynamometry, electromyography, ultrasound imaging) with a musculoskeletal model. RESULTS: We found reduced passive SOL forces (∼30%) (at the same relative levels of muscle stretch) in CHF vs. healthy individuals. This difference was eliminated when force was normalized by physiological cross sectional area, indicating that reduced force output may be most strongly associated with muscle size. Nevertheless, passive force was significantly higher in CHF at a given absolute muscle length (non length-normalized) and likely explained by the shorter muscle slack lengths and optimal muscle lengths measured in CHF compared to the control participants. This later factor may lead to altered performance of the SOL in functional tasks such gait. DISCUSSION: These findings suggest introducing exercise rehabilitation targeting muscle hypertrophy and, specifically for the calf muscles, exercise that promotes muscle lengthening

    Bringing Social Science Into Critical Zone Science: Exploring Smallholder Farmers' Learning Preferences in Chinese Human‐Modified Critical Zones

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    There is a growing global emphasis on sustainable agriculture to reduce human impacts and improve delivery of Sustainable Development Goals (SDGs). With increasing investment in critical zone observatories (CZOs), it becomes important to understand how sustainable agricultural knowledge is produced, shared and used between different groups including farmers, scientists and government. To explore these issues, scientists leading the knowledge exchange (KE) component of a China‐UK CZO program studied three farming regions with contrasting geologies and varying economic levels, using a practice‐based research method. We demonstrate how additional funding for social science research allowed us to understand how farmers access and share farming knowledge through bonding, bridging and linking networks, and how this varies spatially, using interviews and survey questionnaires. Knowledge flows, barriers and opportunities for designing locally suited two‐way KE activities were identified. First, we highlight the need for a more locally, socially embedded and reflexive approach to build trust and better address pressing local environmental challenges. Second, we show how social science can usefully inform KE for collaborative, international development science, to draw on local knowledge, promote research impacts and capacity building while avoiding knowledge mismatches. Lastly, a blueprint for the design and funding of future CZOs, social‐ecological and planetary health research agendas that combine science, social science, local knowledge and KE is presented, including the need for substantive social science research to take place in addition to science research in human‐modified landscapesβ€”enabling the CZ science to be better grounded in, informed by and useful to local communities

    Unwanted incidents during transition of geriatric patients from hospital to home: a prospective observational study

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    <p>Abstract</p> <p>Background</p> <p>Geriatric patients recently discharged from hospital experience increased chance of unplanned readmissions and admission to nursing homes. Several studies have shown that medication-related discrepancies are common. Few studies report unwanted incidents by other factors than medications. In 2002 an ambulatory team (AT) was established within the Department of Geriatrics, St. Olavs University Hospital HF, Trondheim, Norway. The AT monitored the transition of the patients from hospital to home and four weeks after discharge in order to reveal unwanted incidents.</p> <p>The aim of the present study was to describe unwanted incidents registered by the AT among patients discharged from a geriatric evaluation and management unit (GEMU) by character, frequency and stage in the transitional process. Only unwanted incidents with a severity making contact with the primary health care (PHC) necessary were registered.</p> <p>Methods</p> <p>A prospective observational study with patients treated in the GEMU and followed by the AT was performed. Current practice included comprehensive geriatric assessment and management including discharge planning in the GEMU and collaboration with the primary health care on appointments on assistance to be provided after discharge from hospital. Unwanted incidents severe enough to induce contact with the primary health care were registered during the transitional phase and after discharge.</p> <p>Results</p> <p>118 patients (65% female), with mean age 83.2 Β± 6.4 years participated. Median Barthel Index at discharge was 18 (interquartile range 16-19) and median Mini Mental Status Examination 24 (interquartile range 21-26). A total of 146 unwanted incidents were registered in 70 (59%) of the patients. Most frequent were unwanted incidents related to drug prescription regime (32%), exchange of information in and between the GEMU and the primary health care (25%) and service or help provided from the PHC (17%).</p> <p>Conclusions</p> <p>Despite a seemingly well-organised system for transition of patients from the GEMU to their homes, one or more unwanted incidents occurred in most patients during discharge or four weeks post discharge. The study has revealed areas of importance for improving transitional care of geriatric patients.</p

    Submillimetre Transient Science in the Next Decade

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    White paper from the EAO Submillimetre Futures Meeting, 20-23 May 2019, Nanjing, ChinaThis white paper gives a brief summary of the time domain science that has been performed with the JCMT in recent years and highlights the opportunities for continuing work in this field over the next decade. The main focus of this document is the JCMT Transient Survey, a large program initiated in 2015 to measure the frequency and amplitude of variability events associated with protostars in nearby star-forming regions. After summarising the major accomplishments so far, an outline is given for extensions to the current survey, featuring a discussion on what will be possible with the new 850 micron camera that is expected to be installed in late 2022. We also discuss possible applications of submillimetre monitoring to active galactic nuclei, X-ray binaries, asymptotic giant branch stars, and flare stars.Science and Technology Facilities Counci

    Structural insights into Clostridium perfringens delta toxin pore formation

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    Clostridium perfringens Delta toxin is one of the three hemolysin-like proteins produced by C. perfringens type C and possibly type B strains. One of the others, NetB, has been shown to be the major cause of Avian Nectrotic Enteritis, which following the reduction in use of antibiotics as growth promoters, has become an emerging disease of industrial poultry. Delta toxin itself is cytotoxic to the wide range of human and animal macrophages and platelets that present GM2 ganglioside on their membranes. It has sequence similarity with Staphylococcus aureus Ξ²-pore forming toxins and is expected to heptamerize and form pores in the lipid bilayer of host cell membranes. Nevertheless, its exact mode of action remains undetermined. Here we report the 2.4 Γ… crystal structure of monomeric Delta toxin. The superposition of this structure with the structure of the phospholipid-bound F component of S. aureus leucocidin (LukF) revealed that the glycerol molecules bound to Delta toxin and the phospholipids in LukF are accommodated in the same hydrophobic clefts, corresponding to where the toxin is expected to latch onto the membrane, though the binding sites show significant differences. From structure-based sequence alignment with the known structure of staphylococcal Ξ±-hemolysin, a model of the Delta toxin pore form has been built. Using electron microscopy, we have validated our model and characterized the Delta toxin pore on liposomes. These results highlight both similarities and differences in the mechanism of Delta toxin (and by extension NetB) cytotoxicity from that of the staphylococcal pore-forming toxins

    Interactive voice response technology for symptom monitoring and as an adjunct to the treatment of chronic pain

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    Chronic pain is a medical condition that severely decreases the quality of life for those who struggle to cope with it. Interactive voice response (IVR) technology has the ability to track symptoms and disease progression, to investigate the relationships between symptom patterns and clinical outcomes, to assess the efficacy of ongoing treatments, and to directly serve as an adjunct to therapeutic treatment for chronic pain. While many approaches exist toward the management of chronic pain, all have their pitfalls and none work universally. Cognitive behavioral therapy (CBT) is one approach that has been shown to be fairly effective, and therapeutic interactive voice response technology provides a convenient and easy-to-use means of extending the therapeutic gains of CBT long after patients have discontinued clinical visitations. This review summarizes the advantages and disadvantages of IVR technology, provides evidence for the efficacy of the method in monitoring and managing chronic pain, and addresses potential future directions that the technology may take as a therapeutic intervention in its own right

    Hospital Readmission in General Medicine Patients: A Prediction Model

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    Background: Previous studies of hospital readmission have focused on specific conditions or populations and generated complex prediction models. Objective: To identify predictors of early hospital readmission in a diverse patient population and derive and validate a simple model for identifying patients at high readmission risk. Design: Prospective observational cohort study. Patients: Participants encompassed 10,946 patients discharged home from general medicine services at six academic medical centers and were randomly divided into derivation (n = 7,287) and validation (n = 3,659) cohorts. Measurements: We identified readmissions from administrative data and 30-day post-discharge telephone follow-up. Patient-level factors were grouped into four categories: sociodemographic factors, social support, health condition, and healthcare utilization. We performed logistic regression analysis to identify significant predictors of unplanned readmission within 30Β days of discharge and developed a scoring system for estimating readmission risk. Results: Approximately 17.5% of patients were readmitted in each cohort. Among patients in the derivation cohort, seven factors emerged as significant predictors of early readmission: insurance status, marital status, having a regular physician, Charlson comorbidity index, SF12 physical component score, β‰₯1 admission(s) within the last year, and current length of stay >2Β days. A cumulative risk score of β‰₯25 points identified 5% of patients with a readmission risk of approximately 30% in each cohort. Model discrimination was fair with a c-statistic of 0.65 and 0.61 for the derivation and validation cohorts, respectively. Conclusions: Select patient characteristics easily available shortly after admission can be used to identify a subset of patients at elevated risk of early readmission. This information may guide the efficient use of interventions to prevent readmission
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