12 research outputs found

    A Possible Alignment Between the Orbits of Planetary Systems and their Visual Binary Companions

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    Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. We determine that there is statistically significant difference in the inclination distribution of wide-binary systems with transiting planets compared to a control sample, with the probability that the two distributions are the same being 0.0037. This implies that there is an overabundance of planets in binary systems whose orbits are aligned with those of the binary. The overabundance of aligned systems appears to primarily have semimajor axes less than 700 au. We investigate some effects that could cause the alignment and conclude that a torque caused by a misaligned binary companion on the protoplanetary disk is the most promising explanation

    A Theoretically supported experimental study of in situ combustion

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    Bibliography: p. 245-250.The in situ combustion process for the recovery of crude petroleum from underground reservoirs is highly complex. Even on an elemental scale its analysis requires physical simulation of realistic reservoir conditions in order to expose its characteristic, but system-specific, relationships. physical and chemical reaction mechanism In the continuing effort to develop experimental systems for the elemental physical simulation of the combustion process, a new combustion tube system was designed, constructed and successfully tested. The system incorporates a novel combination of: an unconsolidated or consolidated core material use capability; the ability to employ high net external pressures while using a thin wall combustion tube; and the use of a modular design with respect to system components . An experimental program undertaken with the newly developed apparatus included isothermal reaction regime tests, supplementary flow characteristic tests, and an air combustion test series in the 4 MPa to 8 MPa pressure range using different crude oils and core material elements. The series was mechanistic in nature, with the goal being the revelation of the effects of specific experimental condition changes on the performance of combustion propagation. In addition to generating data from observed stable combustion processes, the experimental program revealed that a lower porosity consolidated core element required a greater injected air flux to allow process self-sustenance compared to an otherwise equivalent higher porosity unconsolidated material pack. A novel descriptive model of the high temperature (300°C+) region that uses combustion tube experimental data was developed. Applied to the experimental program stable run periods it revealed relationships among parameters including temperature, fuel quantity, oxygen partial pressure, gas volume flux, gas density , local heat generation rate , and distance with respect to the relatively small moving combustion region. The model application indicated that oxygen consumption was not confined to the highest temperature regions of the stable combustion process. It also gave insight into the experimentally observed flux/porosity - consolidation effect on combustion performance observed in the experimental program

    The impact of team based interprofessional comprehensive assessments on the diagnosis and management of diabetic foot ulcers: A retrospective cohort study.

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    BACKGROUND:Diabetic foot ulcers (DFU) are increasingly prevalent, and associated with significant morbidity, mortality, and cost. An interprofessional approach to DFU management is critical given the etiological complexity involved. This study aimed to assess the impact of an interprofessional team approach on DFU diagnosis and management for a cohort of patients receiving treatment in an Ontario Canada home care setting. METHODS:A retrospective cohort study of patients attending a large regional Community Care Access Centre (CCAC) between February 11, 2013-September 30, 2014 was conducted. Following CCAC referral, patients were assessed by an interprofessional team at the Toronto Regional Wound Healing Centre (TRWHC). Those aged > 18 years with a DFU of > 6 weeks duration were included. The primary outcome was the precision of the initial diagnosis relating to DFU etiology (i.e. neuropathic, ischemic or mixed etiology). Secondary outcomes included wound healing, and infection parameters. Analysis was completed with STATA 13.1 (College Stn., TX) of pre-determined outcomes with 2 sided α of 0.05. RESULTS:A total of 308 patients were screened, and 49 patients (67.3% male) of mean age 64.2 years (SD 13.7) with a diagnosis of DFU > 6 weeks duration were included for analysis. Of these, 95% were referred with unspecified DFU, and were reclassified to a precise diagnosis relating to etiology, including neuropathy, ischemia or neuroischemic etiology following TRWHC assessment (p < 0.001). For secondary outcomes post-assessment, healability assessment was conducted for a greater proportion of patients (100% versus 44%, p < 0.001). Infection was identified in a greater number of patients (p = 0.04), and of the 35 patients, 94.5% had deep and surrounding infection, and 88.0% were initiated on systemic antibiotics. Vascular insufficiency was diagnosed in an additional 14.3% of the cohort (p = 0.03). Offloading/footwear assessment was conducted in all patients compared with 30.6% prior to referral (p < 0.001) Dressing change frequency decreased significantly following TRWHC assessment (pre: 4.31/week; post: 3.54/week; p = 0.03). Pain scores decreased (2.18 to 1.67) on the numerical rating scale but this was not statistically significant at the final TRWHC assessment. Notably, 36.7% (18/49) reported improved quality of life by the second TRWHC encounter. CONCLUSIONS:Interprofessional care teams are associated with improved diagnostic acumen and wound healing outcomes over conventional community care services. Initiatives including best practice interprofessional diabetic foot care pathways are recommended with timely vascular management of ischemia, treatment of deep and surrounding infection as well as the availability of foot care and footwear

    Diabetic foot ulcers: Part I. Pathophysiology and prevention

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    Diabetes mellitus is a serious, life-long condition that is the sixth leading cause of death in North America. Dermatologists frequently encounter patients with diabetes mellitus. Up to 25% of patients with diabetes mellitus will develop diabetic foot ulcers. Foot ulcer patients have an increased risk of amputation and increased mortality rate. The high-risk diabetic foot can be identified with a simplified screening, and subsequent foot ulcers can be prevented. Early recognition of the high-risk foot and timely treatment will save legs and improve patients' quality of life. Peripheral arterial disease, neuropathy, deformity, previous amputation, and infection are the main factors contributing to the development of diabetic foot ulcers. Early recognition of the high-risk foot is imperative to decrease the rates of mortality and morbidity. An interprofessional approach (ie, physicians, nurses, and foot care specialists) is often needed to support patients' needs

    Diabetic foot ulcers: Part II. Management

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    The management of diabetic foot ulcers can be optimized by using an interdisciplinary team approach addressing the correctable risk factors (ie, poor vascular supply, infection control and treatment, and plantar pressure redistribution) along with optimizing local wound care. Dermatologists can initiate diabetic foot care. The first step is recognizing that a loss of skin integrity (ie, a callus, blister, or ulcer) considerably increases the risk of preventable amputations. A holistic approach to wound assessment is required. Early detection and effective management of these ulcers can reduce complications, including preventable amputations and possible mortality
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