131 research outputs found

    Review of Established and Emergent Methods for the Production of C4 Olefins

    Get PDF
    Current production of C4 olefins is dominated by naphtha cracking and butane dehydrogenation, but significant research interest is developing in alternate feedstocks due to an abundance of inexpensive natural gas and bioethanol. The current C4 olefin production methods are costly, make use of already-depleted petroleum resources, and are often hazardous to workers, which forms the impetus for investigation into alternative methods and assessment of their viability as a future means of olefin production. Methods of natural gas conversion to higher order hydrocarbons are discussed, including Fischer-Tropsch synthesis and oxidative methane coupling, each of which could form the first step in a hypothetical natural gas-to-olefins process. The historically common Lebedev, Ostromislensky, and Fripiat methods for 1,3-butadiene production from ethanol feedstocks are described and analyzed, although these processes largely fell out of favor in the decades following World War II in favor of sources derived from naphtha cracking. Another well-known process involving C4 olefins, olefin metathesis, is considered, although the reaction is more commonly used to produce propylene. Biological processes are discussed as well, including the well-known production of bioethanol from sugars and starches, and also more novel processes such as an effort to use genetically engineered microorganisms to produce specific intermediates for olefin production, and in some cases, direct olefin production from these organisms. Finally, several promising schemes are identified and analyzed, in an attempt to compare their potential viability in key areas. Two of the most promising emergent methods today identified in this review are the bio-catalyzed production of 1,4-butanediol and/or butadiene using E. coli, and a microwave radiation-assisted scheme in which methane is selectively dimerized twice to form 1-butene

    Bull Riding Injuries In Central Queensland

    Get PDF
    Background Bull riding is an increasingly popular and growing professional sport in Australia. This is the first national study that investigates bull riding-related injuries. Method A six-year retrospective study of patients admitted to Rockhampton Base Hospital with acute injuries sustained whilst bull riding. Patients were identified from the Rockhampton Hospital international coding system and surgical audit excel databases. Supporting information was found from patient chart review. Results Thirty-eight patients were admitted during the study. Injuries increased from 2008. The most common injuries were to limbs (52%), chest (15%) and brain (10%). Life-threatening injuries were all caused by a direct kick or trampling by the bull; 5% of patients needed air transfer to Brisbane, and 10% to Rockhampton for their acute care. The only complication was infection of open wounds. The average hospital stay was 2.2 (range= 1-5, SD= 1.1) days and 64% of patients required operative intervention. Conclusion Patients that had been kicked or trampled should be identified as having potentially life-threatening injuries, and transferred for review at an appropriate facility. Due to the high risk of infection all contaminated wounds should be washed out formally and receive antibiotics. Protective equipment should be encouraged among riders

    Structural and optical-properties of CdTe and CdMnTe films

    Get PDF
    We undertook a detailed investigation of the structural- and optical-properties of CdTe- and Cd1-xMnxTe-semiconductor films deposited by close-spaced vacuum sublimation using thermal evaporation on non-oriented substrates. From our structural- and phase-analysis of the layers, we obtained information on their structure, deformations, grain size, and content of dislocations for films deposited at different substrate temperatures. We considered that despite the presence of defects in the crystals, the films offer promise for fabrication into x-ray detectors. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3013

    Hip fracture evaluation with alternatives of total hip arthroplasty versus hemiarthroplasty (HEALTH): protocol for a multicentre randomised trial

    Get PDF
    Introduction: Hip fractures are a leading cause of mortality and disability worldwide, and the number of hip fractures is expected to rise to over 6 million per year by 2050. The optimal approach for the surgical management of displaced femoral neck fractures remains unknown. Current evidence suggests the use of arthroplasty; however, there is lack of evidence regarding whether patients with displaced femoral neck fractures experience better outcomes with total hip arthroplasty (THA) or hemiarthroplasty (HA). The HEALTH trial compares outcomes following THA versus HA in patients 50 years of age or older with displaced femoral neck fractures. Methods and analysis: HEALTH is a multicentre, randomised controlled trial where 1434 patients, 50 years of age or older, with displaced femoral neck fractures from international sites are randomised to receive either THA or HA. Exclusion criteria include associated major injuries of the lower extremity, hip infection(s) and a history of frank dementia. The primary outcome is unplanned secondary procedures and the secondary outcomes include functional outcomes, patient quality of life, mortality and hiprelated complications—both within 2 years of the initial surgery. We are using minimisation to ensure balance between intervention groups for the following factors: age, prefracture living, prefracture functional status, American Society for Anesthesiologists (ASA) Class and centre number. Data analysts and the HEALTH Steering Committee are blinded to the surgical allocation throughout the trial. Outcome analysis will be performed using a χ2 test (or Fisher’s exact test) and Cox proportional hazards modelling estimate. All results will be presented with 95% CIs. Ethics and dissemination: The HEALTH trial has received local and McMaster University Research Ethics Board (REB) approval (REB#: 06-151). Results: Outcomes from the primary manuscript will be disseminated through publications in academic journals and presentations at relevant orthopaedic conferences. We will communicate trial results to all participating sites. Participating sites will communicate results with patients who have indicated an interest in knowing the results. Trial registration number: The HEALTH trial is registered with clinicaltrials.gov (NCT00556842)

    Efficient clinical-grade γ-retroviral vector purification by high-speed centrifugation for CAR T cell manufacturing

    Get PDF
    γ-Retroviral vectors (γ-RV) are powerful tools for gene therapy applications. Current clinical vectors are produced from stable producer cell lines which require minimal further downstream processing, while purification schemes for γ-RV produced by transient transfection have not been thoroughly investigated. We aimed to develop a method to purify transiently produced γ-RV for early clinical studies. Here, we report a simple one-step purification method by high-speed centrifugation for γ-RV produced by transient transfection for clinical application. High-speed centrifugation enabled the concentration of viral titers in the range of 107-108 TU/mL with >80% overall recovery. Analysis of research-grade concentrated vector revealed sufficient reduction in product- and process-related impurities. Furthermore, product characterization of clinical-grade γ-RV by BioReliance demonstrated two-logs lower impurities per transducing unit compared with regulatory authority-approved stable producer cell line vector for clinical application. In terms of CAR T cell manufacturing, clinical-grade γ-RV produced by transient transfection and purified by high-speed centrifugation was similar to γ-RV produced from a clinical-grade stable producer cell line. This method will be of value for studies using γ-RV to bridge vector supply between early- and late-stage clinical trials

    A trial assessing N-3 as treatment for injury-induced cachexia (ATLANTIC trial): does a moderate dose fish oil intervention improve outcomes in older adults recovering from hip fracture?

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Proximal femoral fractures are associated with increased morbidity and mortality. Pre-existing malnutrition and weight loss amongst this patient group is of primary concern, with conventional nutrition support being largely ineffective. The inflammatory response post proximal femoral fracture surgery and the subsequent risk of cachexia may explain the inability of conventional high energy high protein management to produce an anabolic response amongst these patients. Omega-3 fatty acids derived from fish oils have been extensively studied for their anti-inflammatory benefits. Due to their anti-inflammatory properties, the benefit of fish oil combined with individualized nutrition support amongst proximal femoral fracture patients post surgery is an attractive potential therapeutic strategy. The aim of the ATLANTIC trial is to assess the potential benefits of an anti-inflammatory dose of fish oil within the context of a 12 week individualised nutrition program, commencing seven days post proximal femoral fracture surgery.</p> <p>Methods/Design</p> <p>This randomized controlled, double blinded trial, will recruit 150 community dwelling elderly patients aged ≥65 years, within seven days of surgery for proximal femoral fracture. Participants will be randomly allocated to receive either a 12 week individualized nutrition support program complemented with 20 ml/day anti-inflammatory dose fish oil (~3.6 g eicosapentaenoic acid, ~2.4 g docosahexanoic acid; intervention), or, a 12 week individualized nutrition support program complemented with 20 ml/day low dose fish oil (~0.36 g eicosapentaenoic acid, ~0.24 g docosahexanoic acid; control).</p> <p>Discussion</p> <p>The ATLANTIC trial is the first of its kind to provide fish oil combined with individualized nutrition therapy as an intervention to address the inflammatory response experienced post proximal femoral fracture surgery amongst elderly patients. The final outcomes of this trial will assist clinicians in the development of effective and alternative treatment methods post proximal femoral fracture surgery which may ultimately result in a reduction in systemic inflammation, loss of weight and lean muscle and improvements in nutritional status, mobility, independence and quality of life among elderly patients.</p> <p>Trial Registration</p> <p>ACTRN12609000241235</p

    ESPEN Guideline: Clinical Nutrition in inflammatory bowel disease

    Get PDF
    Introduction: The ESPEN guideline presents a multidisciplinary focus on clinical nutrition in inflammatory bowel disease (IBD). Methodology: The guideline is based on extensive systematic review of the literature, but relies on expert opinion when objective data were lacking or inconclusive. The conclusions and 64 recommendations have been subject to full peer review and a Delphi process in which uniformly positive responses (agree or strongly agree) were required. Results: IBD is increasingly common and potential dietary factors in its aetiology are briefly reviewed. Malnutrition is highly prevalent in IBD – especially in Crohn's disease. Increased energy and protein requirements are observed in some patients. The management of malnu-trition in IBD is considered within the general context of support for malnourished patients. Treatment of iron deficiency (parenterally if necessary) is strongly recommended. Routine provision of a special diet in IBD is not however supported. Parenteral nutrition is indicated only when enteral nutrition has failed or is impossible. The recommended perioperative man-agement of patients with IBD undergoing surgery accords with general ESPEN guidance for patients having abdominal surgery. Probiotics may be helpful in UC but not Crohn's disease. Primary therapy using nutrition to treat IBD is not supported in ulcerative colitis, but is mod-erately well supported in Crohn's disease, especially in children where the adverse conse-quences of steroid therapy are proportionally greater. However, exclusion diets are generally not recommended and there is little evidence to support any particular formula feed when nutritional regimens are constructed. Conclusions: Available objective data to guide nutritional support and primary nutritional therapy in IBD are presented as 64 recommendations, of which 9 are very strong recom-mendations (grade A), 22 are strong recommendations (grade B) and 12 are based only on sparse evidence (grade 0); 21 recommendations are good practice points (GPP)
    corecore