319 research outputs found

    A Comparative Analysis for Land Utilization:Steel and R/C Interlaced Structures

    Get PDF
    In architecture, interlace structural concept is considered as a new design approach for cosmopolitan cities with high density to minimize the land use and increase the interaction. With various architectural approach, land resources can be minimized by this interlace concept for residential complexes. Such buildings will eliminate the reduction of land resource problem and on the other side safety measures in structural design is incorporated by interlace concept of buildings. This new concept can be constructed steel or reinforced concrete. In this paper, an analytical approach has been presented for these buildings in architecture and structural design. In the research, design considerations were taken for interlaced structures with reinforced concrete and steel. Components of steel structure, isolated footing, and columns. This paper is presenting a step wise process for interlance structures. They are identification of project area, layout and model preparation, analysis and design of concrete interlaced structure, analysis and design of steel interlaced structure, drafting of the plans and costing and estimation of the structures. Comparison of both reinforced concrete and steel structures were carried out. The main aim of the paper is to provide a comparison between steel and concrete interlaced structure. A cost estimation was carried out to determine optimum design and construction for interlaced structures

    Variations in Practice Patterns among Neurosurgeons and Orthopaedic Surgeons in the Management of Spinal Disorders

    Get PDF
    Study design: This is a case series.Purpose: We wanted to identify variations in the practice patterns among neurosurgeons and orthopedic surgeons for the management of spinal disorders.Overview of literature: Spinal disorders are common in the clinical practice of both neurosurgeons and orthopedic surgeons. It has been observed that despite the availability of various guidelines, there is lack of consensus among surgeons about the management of various disorders.Methods: A questionnaire was distributed, either directly or via e-mail, to the both the neurosurgeons and orthopedic surgeons who worked at 5 tertiary care centers within a single region of Korea. The surgeons were working either in private practice or in academic institutions. The details of the questionnaire included demographic details and the specialty (orthopedic/neurosurgeon). The surgeons were classified according to the level of experience as up to 5 years, 6-10 years and \u3e 10 years. Questions were asked about the approach to lumbar discectomy (fragmentectomy or aggressive disc removal), using steroids for treating discitis, the fusion preference for spondylolisthesis, the role of an orthosis after fusion, the preferred surgical approach for spinal stenosis, the operative approach for spinal trauma (early within 72 hours or late \u3e 72 hours) and the role of surgery in complete spinal cord injury. The data was analyzed using SPSS ver 16. p-values \u3c 0.05 were considered to be significant.Results: Of the 30 surgeons who completed the questionnaire, 20 were neurosurgeons and 10 were orthopedic surgeons. Statistically significant differences were observed for the management of spinal stenosis, spondylolisthesis, using an orthosis after fusion, the type of lumbar discectomy and the value of surgical intervention after complete spinal cord injury.Conclusions: Our results suggest that there continues to exist a statistically significant lack of consensus among neurosurgeons and orthopedic spine surgeons when considering using an orthosis after fusion, the type of discectomy and the value of intervention after complete spinal injury

    Spinal involvement in mucopolysaccharidosis IVA (Morquio-Brailsford or Morquio A syndrome): presentation, diagnosis and management.

    Get PDF
    Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio-Brailsford or Morquio A syndrome, is a lysosomal storage disorder caused by a deficiency of the enzyme N-acetyl-galactosamine-6-sulphate sulphatase (GALNS). MPS IVA is multisystemic but manifests primarily as a progressive skeletal dysplasia. Spinal involvement is a major cause of morbidity and mortality in MPS IVA. Early diagnosis and timely treatment of problems involving the spine are critical in preventing or arresting neurological deterioration and loss of function. This review details the spinal manifestations of MPS IVA and describes the tools used to diagnose and monitor spinal involvement. The relative utility of radiography, computed tomography (CT) and magnetic resonance imaging (MRI) for the evaluation of cervical spine instability, stenosis, and cord compression is discussed. Surgical interventions, anaesthetic considerations, and the use of neurophysiological monitoring during procedures performed under general anaesthesia are reviewed. Recommendations for regular radiological imaging and neurologic assessments are presented, and the need for a more standardized approach for evaluating and managing spinal involvement in MPS IVA is addressed

    Thermal Conductivity of Carbon Nanotubes and their Polymer Nanocomposites: A Review

    Get PDF
    Thermally conductive polymer composites offer new possibilities for replacing metal parts in several applications, including power electronics, electric motors and generators, heat exchangers, etc., thanks to the polymer advantages such as light weight, corrosion resistance and ease of processing. Current interest to improve the thermal conductivity of polymers is focused on the selective addition of nanofillers with high thermal conductivity. Unusually high thermal conductivity makes carbon nanotube (CNT) the best promising candidate material for thermally conductive composites. However, the thermal conductivities of polymer/CNT nanocomposites are relatively low compared with expectations from the intrinsic thermal conductivity of CNTs. The challenge primarily comes from the large interfacial thermal resistance between the CNT and the surrounding polymer matrix, which hinders the transfer of phonon dominating heat conduction in polymer and CNT. This article reviews the status of worldwide research in the thermal conductivity of CNTs and their polymer nanocomposites. The dependence of thermal conductivity of nanotubes on the atomic structure, the tube size, the morphology, the defect and the purification is reviewed. The roles of particle/polymer and particle/particle interfaces on the thermal conductivity of polymer/CNT nanocomposites are discussed in detail, as well as the relationship between the thermal conductivity and the micro- and nano-structure of the composite

    Recombinant factor VIIa for the prevention and treatment of bleeding in patients without haemophilia

    Get PDF
    This review is published as a Cochrane Review in the Cochrane Database of Systematic Reviews 2012, Issue 3. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Review.BACKGROUND: Recombinant factor VIIa (rFVIIa) is licensed for use in patients with haemophilia and inhibitory allo-antibodies and for prophylaxis and treatment of patients with congenital factor VII deficiency. It is also used for off-license indications to prevent bleeding in operations where blood loss is likely to be high, and/or to stop bleeding that is proving difficult to control by other means. This is the third version of the 2007 Cochrane review on the use of recombinant factor VIIa for the prevention and treatment of bleeding in patients without haemophilia, and has been updated to incorporate recent trial data. OBJECTIVES: To assess the effectiveness of rFVIIa when used therapeutically to control active bleeding or prophylactically to prevent (excessive) bleeding in patients without haemophilia. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and other medical databases up to 23 March 2011. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing rFVIIa with placebo, or one dose of rFVIIa with another, in any patient population (except haemophilia). Outcomes were mortality, blood loss or control of bleeding, red cell transfusion requirements, number of patients transfused and thromboembolic adverse events. DATA COLLECTION AND ANALYSIS: Two authors independently assessed potentially relevant studies for inclusion, extracted data and examined risk of bias. We considered prophylactic and therapeutic rFVIIa studies separately. MAIN RESULTS: Twenty-nine RCTs were included: 28 were placebo-controlled, double-blind RCTs and one compared different doses of rFVIIa. In the 'Risk of bias' assessment, most studies were found to have some threats to validity although therapeutic RCTs were found to be less prone to bias than prophylactic RCTs.Sixteen trials involving 1361 participants examined the prophylactic use of rFVIIa; 729 received rFVIIa. There was no evidence of mortality benefit (risk ratio (RR) 1.04; 95% confidence interval (CI) 0.55 to 1.97). There was decreased blood loss (mean difference (MD) -297 mL; 95% CI -416 to -178) and decreased red cell transfusion requirements (MD -261 mL; 95% CI -367 to -154) with rFVIIa treatment; however, these values were likely overestimated due to the inability to incorporate data from trials (four RCTs in the outcome of blood loss and three RCTs in the outcome of transfusion requirements) showing no difference of rFVIIa treatment compared to placebo. There was a trend in favour of rFVIIa in the number of participants transfused (RR 0.85; 95% CI 0.72 to 1.01). However, there was a trend against rFVIIa with respect to thromboembolic adverse events (RR 1.35; 95% CI 0.82 to 2.25).Thirteen trials involving 2929 participants examined the therapeutic use of rFVIIa; 1878 received rFVIIa. There were no outcomes where any observed advantage or disadvantage of rFVIIa over placebo could not have been observed by chance alone. There was a trend in favour of rFVIIa for reducing mortality (RR 0.91; 95% CI 0.78 to 1.06). However, there was a trend against rFVIIa for increased thromboembolic adverse events (RR 1.14; 95% CI 0.89 to 1.47).When all trials were pooled together to examine the risk of thromboembolic events, a significant increase in total arterial events was observed (RR 1.45; 95% CI 1.02 to 2.05). AUTHORS' CONCLUSIONS: The effectiveness of rFVIIa as a more general haemostatic drug, either prophylactically or therapeutically, remains unproven. The results indicate increased risk of arterial events in patients receiving rFVIIa. The use of rFVIIa outside its current licensed indications should be restricted to clinical trials

    Tibiofibular syndesmosis in acute ankle fractures: additional value of an oblique MR image plane

    Get PDF
    Item does not contain fulltextOBJECTIVE: To evaluate the additional value of a 45� oblique MRI scan plane for assessing the anterior and posterior distal tibiofibular syndesmotic ligaments in patients with an acute ankle fracture. MATERIALS AND METHODS: Prospectively, data were collected for 44 consecutive patients with an acute ankle fracture who underwent a radiograph (AP, lateral, and mortise view) as well as an MRI in both the standard three orthogonal planes and in an additional 45� oblique plane. The fractures on the radiographs were classified according to Lauge-Hansen (LH). The anterior (ATIFL) and posterior (PTIFL) distal tibiofibular ligaments, as well as the presence of a bony avulsion in both the axial and oblique planes was evaluated on MRI. MRI findings regarding syndesmotic injury in the axial and oblique planes were compared to syndesmotic injury predicted by LH. Kappa and the agreement score were calculated to determine the interobserver agreement. The Wilcoxon signed rank test and McNemar's test were used to compare the two scan planes. RESULTS: The interobserver agreement (?) and agreement score [AS (\%)] regarding injury of the ATIFL and PTIFL and the presence of a fibular or tibial avulsion fracture were good to excellent in both the axial and oblique image planes (? 0.61-0.92, AS 84-95\%). For both ligaments the oblique image plane indicated significantly less injury than the axial plane (p?<?0.001). There was no significant difference in detection of an avulsion fracture in the axial or oblique plane, neither anteriorly (p?=?0.50) nor posteriorly (p?=?1.00). With syndesmotic injury as predicted by LH as comparison, the specificity in the oblique MR plane increased for both anterior (to 86\% from 7\%) and posterior (to 86\% from 48\%) syndesmotic injury when compared to the axial plane. CONCLUSION: Our results show the additional value of an 45� oblique MR image plane for detection of injury of the anterior and posterior distal tibiofibular syndesmoses in acute ankle fractures. Findings of syndesmotic injury in the oblique MRI plane were closer to the diagnosis as assumed by the Lauge-Hansen classification than in the axial plane. With more accurate information, the surgeon can better decide when to stabilize syndesmotic injury in acute ankle fractures

    Review of phase change emulsions (PCMEs) and their applications in HVAC systems

    Get PDF
    Phase change material emulsions (PCMEs) are multifunctional fluids consisting of phase change materials (PCMs) and carrier fluids. PCMEs could be potential candidates as heat transfer media in heating, ventilation and air conditioning (HVAC) systems. This is mainly because PCME could take advantage of its high heat capacity to reduce flow rate and thus saving pumping power whilst delivering the same amount of cooling effect. PCME can also simultaneously act as cold storage to shift peak-load to off-peak time and improve the COP of systems. However, the optimum design of integrated system requires a good understanding of flow behaviour and heat transfer characteristics of PCMEs. In this paper, comprehensive reviews of their thermo-physical properties and potential applications as thermal energy storage and as alternative heat transfer fluids in air conditioning systems have been carried out to establish their limitations for future research

    Treatment of displaced intra-articular calcaneal fractures by ligamentotaxis: current concepts’ review

    Get PDF
    Introduction: A large variety of therapeutic modalities for calcaneal fractures have been described in the literature. No single treatment modality for displaced intra-articular calcaneal fractures has proven superior over the other. This review describes and compares the different percutaneous distractional approaches for intra-articular calcaneal fractures. The history, technique, anatomical and fracture considerations, limitations and the results of different distractional approaches reported in the literature are reviewed. Method: Literature review on different percutaneous distractional approaches for displaced intra-articular calcaneal fractures. Results: Eight studies in which application of a distraction technique was used for the treatment of calcaneal fractures were identified. Because of the use of different classification, techniques, and outcome scoring systems, a meta-analysis was not possible. A literature review reveals overall fair to poor result in 10-29% of patients. Ten up to 26% of patients are unable to return to work after percutaneous treatment of their fracture. A secondary arthrodesis has to be performed in 2-15% of the cases. Infectious complications occur in 2-15%. Some loss of reduction is reported in 4-67%. Conclusion: Percutaneous distractional reduction and fixation appears to be a safe technique with overall good results and an acceptable complication rate, compared with other treatment modalities for displaced intra-articular calcaneal fractures. A meta-analysis, based on Cochrane Library criteria is not possible, because of a lack of level 1 and 2 trials on this subject
    corecore