191 research outputs found

    Powered Wheelchair Platform for Assistive Technology Development

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    Literature shows that numerous wheelchair platforms, of various complexities, have been developed and evaluated for Assistive Technology purposes. However there has been little consideration to providing researchers with an embedded system which is fully compatible, and communicates seamlessly with current manufacturer's wheelchair systems. We present our powered wheelchair platform which allows researchers to mount various inertial and environment sensors, and run guidance and navigation algorithms which can modify the human desired joystick trajectory, so as to assist users with negotiating obstacles, and moving from room to room. We are also able to directly access other currently manufactured human input devices and integrate new and novel input devices into the powered wheelchair platform for clinical and research assessment

    The C(3P) + NH3 reaction in interstellar chemistry: II. Low temperature rate constants and modeling of NH, NH2 and NH3 abundances in dense interstellar clouds

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    A continuous supersonic flow reactor has been used to measure rate constants for the C + NH3 reaction over the temperature range 50 to 296 K. C atoms were created by the pulsed laser photolysis of CBr4. The kinetics of the title reaction were followed directly by vacuum ultra-violet laser induced fluorescence (VUV LIF) of C loss and through H formation. The experiments show unambiguously that the reaction is rapid at 296 K, becoming faster at lower temperatures, reaching a value of 1.8 10-10 cm3 molecule-1 s-1 at 50 K. As this reaction is not currently included in astrochemical networks, its influence on interstellar nitrogen hydride abundances is tested through a dense cloud model including gas-grain interactions. In particular, the effect of the ortho-to-para ratio of H2 which plays a crucial role in interstellar NH3 synthesis is examined

    Evaluation of Safe Firearm Storage Messaging in a Sample of Firearm-Owning US Military Service Members.

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    Importance Nearly two-thirds of military suicides involve firearms, and safe firearm storage is rare. Objective To examine whether US military service members endorse greater openness to safe firearm storage depending on the content of the visual message they are randomly assigned to view. Design, Setting, and Participants This comparative effectiveness study used a 3 × 2 × 2 factorial design to randomize US military service members to view 1 of 12 visual messages on safe firearm storage. Willingness to use safe firearm storage practices was assessed immediately before and after exposure to the message. Participants were recruited using the KnowledgePanel Calibration approach. Inclusion criteria included current membership in the US military and current firearm ownership. The KnowledgePanel sample was fielded from December 3 to 27, 2021, with a 76% completion rate and 45 individuals determined to be qualified (28% qualification rate). The opt-in sample was fielded December 7, 2021, through January 4, 2022, with 699 individuals (3%) qualified and 674 included in the final data set. Exposures Messages shared the same image and text on safe firearm storage but varied in messenger occupation (eg, primary care physician, security forces, or combat controller), the presence of text validating the perspective of firearm owners, and the presence of text validating the drive for home protection. Main Outcomes and Measures Outcomes included changes in willingness to use 4 at-home (unloaded, separate from ammunition, in a locked location, and with a locking device) and 3 away-from-home (with family or friend, at a firearm retailer, or at a law enforcement agency) firearm storage practices. All analyses, including sample descriptives, are based on weighted data. Results Of the 719 individuals in the data set, 367 (median [range] age, 33.64 [18-86] years; 80.4% male; 71.4% White) who endorsed not currently storing firearms using the methods assessed were included in analyses. In a multivariate analysis of variance, a significant interaction was found among time, messenger profession, gun-friendly text, and home protection text across all outcomes (Wilks’ λ F = 2.09; P = .01; pη2 = 0.040); however, in a post hoc repeated-measures analysis of variance, the interaction was statistically significant only for storing firearms away from home with a trusted family member or friend (F = 5.42; P = .005; pη2 = 0.030). The profession of the messenger was more consistently associated with shifts in willingness than was the message content, although this varied across storage options. Conclusions and Relevance The findings of this comparative effectiveness study suggest that several combinations of messenger and content may be associated with willingness to endorse safe firearm storing practices, with particularly consistent positive findings for messages featuring security forces. The scalability and dosage potential of this intervention may render visual messaging valuable for promoting safe firearm storage at the population level

    Flow tube studies of the C(3P) reactions with ethylene and propylene

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    International audienceProduct detection studies of C(3P) atom reactions with ethylene, C2H4(X1Ag) and propylene, C3H6(X1A′) are carried out in a flow tube reactor at 332 K and 4 Torr (553.3 Pa) under multiple collision conditions. Ground state carbon atoms are generated by 193 nm laser photolysis of carbon suboxide, C3O2 in a buffer of helium. Thermalized reaction products are detected using tunable VUV photoionization and time of flight mass spectrometry. For C(3P) + ethylene, propargyl (C3H3) is detected as the only molecular product in agreement with previous studies on this reaction. The temporal profiles of the detected ions are used to discriminate C(3P) reaction products from side reaction products. For C(3P) + propylene, two reaction channels are identified through the detection of methyl (CH3) and propargyl (C3H3) radicals for the first channel and C4H5 for the second one. Franck–Condon Factor simulations are employed to infer the C4H5-isomer distribution. The measured 1:4 ratio for the i-C4H5 isomer relative to the methylpropargyl isomers is similar to the C4H5 isomer distribution observed in low-pressure flames and differs from crossed molecular beams data. The accuracy of these isomer distributions is discussed in view of large uncertainties on the photoionization spectra of the pure C4H5 isomer

    How Distress Tolerance Mediates the Relationship Between Posttraumatic Stress Disorder and the Interpersonal Theory of Suicide Constructs in a U.S. Military Sample

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    Objectives Despite the general suicide rate within the military being comparable to the general population when comparing peers, there are certain branches of the military that have elevated risk. Specifically, the U.S. National Guard has suicide rates that are constantly higher than other military branches and civilian peers. The National Guard are a unique military population in which they frequently transition between military and civilian life. With these unique experiences and heightened risk, military suicide prevention efforts may benefit from further research within this population. Posttraumatic stress disorder (PTSD) is another concern amongst military personnel and has been linked to suicidal behavior. Methods The current study examined the indirect effects that distress tolerance, a protective factor against suicide, has on the relationship between PTSD and constructs within a well‐validated theory for suicide (the Interpersonal‐Psychological Theory for suicidal behaviors) in a sample of U.S. Army National Guard personnel. Results Results indicated that distress tolerance had a significant indirect effect on the relationship between PTSD and thwarted belongingness, perceived burdensomeness, and capability for suicide. Conclusions These findings are consistent with previous literature examining the relationship between distress tolerance and our outcome variables. These results could have important clinical implications, mainly that intervention strategies targeting distress tolerance could have significant impacts on suicide‐relate thoughts

    A survey of internal and family medicine residents: Assessment of disability-specific education and knowledge.

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    BACKGROUND: The literature suggests that primary care physicians are inadequately educated in the care of people with disabilities. No study to date has evaluated whether internal medicine (IM) and family medicine (FM) residents have received disability-specific education or their level of comfort in caring for people with physical disabilities. OBJECTIVES: To assess IM and FM residents\u27 receipt of disability-specific education during medical school and residency; to evaluate their self-reported comfort in managing secondary conditions associated with physical disabilities and in coordinating therapies and services for individuals with disabilities; to gauge their interest in receiving disability-specific education. METHODS: An on-line survey distributed to residents at a convenience sample of ten academic IM and FM residency programs in the northeastern United States. Participants (n = 176) were asked about their socio-demographic and training-specific characteristics and their self-assessed ability to manage secondary conditions associated with physical disabilities and coordinate care and services for individuals with disabilities. Chi Square tests were used to compare participant characteristics and outcomes. RESULTS: Few participants had received disability-specific education during medical school or residency (34.6% and 11.2%, respectively), and nearly all (96.0%) expressed interest in receiving more. Small minorities reported feeling comfortable managing common secondary conditions or in coordinating therapies and services for individuals with disabilities. CONCLUSION: Although one-fifth of adult Americans have a disability, few of our participating IM and FM residents had received disability-specific education or felt comfortable managing the care of people living with disabilities. Our results indicate a need to develop and disseminate disability-specific curricula

    The diagnostic value of biomarkers (SteatoTest) for the prediction of liver steatosis

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    BACKGROUND: Biopsy is the usual gold standard for liver steatosis assessment. The aim of this study was to identify a panel of biomarkers (SteatoTest), with sufficient predictive values, for the non-invasive diagnosis of steatosis in patients with or without chronic liver disease. Biomarkers and panels were assessed in a training group of consecutive patients with chronic hepatitis C and B, alcoholic liver disease, and non-alcoholic fatty liver disease, and were validated in two independent groups including a prospective one. Steatosis was blindly assessed by using a previously validated scoring system. RESULTS: 310 patients were included in the training group; 434 in three validation groups; and 140 in a control group. SteatoTest was constructed using a combination of the 6 components of FibroTest-ActiTest plus body mass index, serum cholesterol, triglycerides, and glucose adjusted for age and gender. SteatoTest area under the ROC curves was 0.79 (SE = 0.03) in the training group; 0.80 (0.04) in validation group 1; 0.86 (0.03) in validation group 2; and 0.72 (0.05) in the validation group 3 – all significantly higher than the standard markers: γ-glutamyl-transpeptidase or alanine aminotransferase. The median SteatoTest value was 0.13 in fasting controls; 0.16 in non-fasting controls; 0.31 in patients without steatosis; 0.39 in grade 1 steatosis (0–5%); 0.58 in grade 2 (6–32%); and 0.74 in grade 3–4 (33–100%). For the diagnosis of grade 2–4 steatosis, the sensitivity of SteatoTest at the 0.30 cut-off was 0.91, 0.98, 1.00 and 0.85 and the specificity at the 0.70 cut-off was 0.89, 0.83, 0.92, 1.00, for the training and three validation groups, respectively. CONCLUSION: SteatoTest is a simple and non-invasive quantitative estimate of liver steatosis and may reduce the need for liver biopsy, particularly in patients with metabolic risk factor

    Restoring Pre-Industrial CO\u3csub\u3e2\u3c/sub\u3e Levels While Achieving Sustainable Development Goals

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    © 2020 by the authors. Unless humanity achieves United Nations Sustainable Development Goals (SDGs) by 2030 and restores the relatively stable climate of pre-industrial CO2 levels (as early as 2140), species extinctions, starvation, drought/floods, and violence will exacerbate mass migrations. This paper presents conceptual designs and techno-economic analyses to calculate sustainable limits for growing high-protein seafood and macroalgae-for-biofuel. We review the availability of wet solid waste and outline the mass balance of carbon and plant nutrients passing through a hydrothermal liquefaction process. The paper reviews the availability of dry solid waste and dry biomass for bioenergy with CO2 capture and storage (BECCS) while generating Allam Cycle electricity. Sufficient wet-waste biomass supports quickly building hydrothermal liquefaction facilities. Macroalgae-for-biofuel technology can be developed and straightforwardly implemented on SDG-achieving high protein seafood infrastructure. The analyses indicate a potential for (1) 0.5 billion tonnes/yr of seafood; (2) 20 million barrels/day of biofuel from solid waste; (3) more biocrude oil from macroalgae than current fossil oil; and (4) sequestration of 28 to 38 billion tonnes/yr of bio-CO2. Carbon dioxide removal (CDR) costs are between 25–33% of those for BECCS with pre-2019 technology or the projected cost of air-capture CDR

    Valine Aminoacyl-tRNA Synthetase Promotes Therapy Resistance in Melanoma

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    Transfer RNA dynamics contribute to cancer development through regulation of codon-specific messenger RNA translation. Specific aminoacyl-tRNA synthetases can either promote or suppress tumourigenesis. Here we show that valine aminoacyl-tRNA synthetase (VARS) is a key player in the codon-biased translation reprogramming induced by resistance to targeted (MAPK) therapy in melanoma. The proteome rewiring in patient-derived MAPK therapy-resistant melanoma is biased towards the usage of valine and coincides with the upregulation of valine cognate tRNAs and of VARS expression and activity. Strikingly, VARS knockdown re-sensitizes MAPK-therapy-resistant patient-derived melanoma in vitro and in vivo. Mechanistically, VARS regulates the messenger RNA translation of valine-enriched transcripts, among which hydroxyacyl-CoA dehydrogenase mRNA encodes for a key enzyme in fatty acid oxidation. Resistant melanoma cultures rely on fatty acid oxidation and hydroxyacyl-CoA dehydrogenase for their survival upon MAPK treatment. Together, our data demonstrate that VARS may represent an attractive therapeutic target for the treatment of therapy-resistant melanoma
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