Centrifuge modelling to determine the influence of pile stiffness on pile capacity

The stiffness of piles relates to their ability to resist deformation in response to an applied force. The modulus of elasticity of an uncracked concrete piles typically varies between 30-40kN/m2. Under axial loading these high stiffness piles transfer the load through the pile to the base. This results in low mobilisation of shaft friction as the stiff pile displaces uniformly and therefore the magnitude of skin friction along the entire length of the pile is small. In addition, base resistance of deep piles is mobilised at very high loads which may exceed the working load of the pile shaft. The adhesion factor, α, for bored piles in London Clay can range between 0.45 and 0.6 suggesting that a significant proportion of the soil strength cannot be mobilised. This low mobilisation of shaft resistance means that the ultimate bearing capacity is much reduced. The research investigated the behaviour of a low stiffness pile under axial load and compared this with a conventional high stiffness pile. The results demonstrated that the low stiffness pile exhibited marginally greater capacity at working load and a noticeably improved capacity at ultimate load

A study of an operative outcome of a basitrochanteric fractures of the hip treated by dynamic hip screw and enders nail with percutaneous canulated cancellous screw

Background: Basicervical or cervicotrochanteric fracture of the femur is considered stable variety of fracture pattern. Most common incidence is seen in elderly patient and in young patient with probably high energy trauma. Appropriate Osteosynthesis confers excellent outcome when reduction is optimally achieved.Methods: 86 basitrochanteric fractures had been treated with enders nail or dynamic hip screw (DHS) at our institute by a single surgeon. Implant selection was done purely based on plain radiograph, associated co-morbidities and fracture geometry. Patients had been followed up at 1 month, 3 month and 6 month.Results: In our study there were 86 patients out of which 63 patients (73.25%) were treated with enders nail and 23 patients (26.74%) were treated with DHS. Mean age of patients was 57 years. We noted minimum follow up of 8 months while maximum follow up of 4.5 years where as mean follow up duration is 18 months. We almost noted excellent to fair results in both groups.Conclusions: Most of the implants in basitrochanteric fractures worked on control collapse principle. Both DHS and enders nail with percutaneous cc screw follow this principle and when used with a proper technique, optimal reduction usually fetch the favourable outcomes with minimalistic approach

Optimization of cogging torque in interior permanent magnet synchronous motor using optimum magnet v-angle

Introduction. At present, the most important requirement in the field of electrical engineering is the better utilization of electrical power, due to its increasing demand and not-so-increasing availability. A permanent magnet synchronous motor (PMSM) is increasingly gaining popularity in various household and industrial applications because of its superior performance compared to conventional electrical motors. Purpose. PMSM is designed based on the selection of various design variables and optimized to fulfill the same. Being superiorly advantageous over other motors, PMSM has the major disadvantage of higher cogging torque. Higher cogging torque generates torque ripple in the PMSM motor leading to various problems like vibration, rotor stress, and noisy operation during starting and steady state. The designer should aim to reduce the cogging torque at the design stage itself for overall better performance. Methods. An interior rotor v-shaped web-type PMSM is designed and its performance analysis is carried out using finite element analysis (FEA). Magnet v-angle is optimized with the objective of cogging torque reduction. Performance comparison is carried out between the optimized motor and the initially designed motor with FEA. Novelty. Magnet v-angle analysis is performed on the same keeping all other parameters constant, to obtain minimum cogging torque. The proposed method is practically viable as it does not incur extra costs and manufacturing complexity. Practical value. It is observed that the magnet v-angle is an effective technique in the reduction of cogging torque. Cogging torque is reduced from 0.554 N×m to 0.452 N×m with the application of the magnet v-angle optimization technique.Вступ. В даний час найважливішою вимогою в галузі електротехніки є найкраще використання електроенергії через зростаючу потребу в ній і не настільки зростаючу доступність. Синхронний двигун з постійними магнітами (СДПМ) набуває все більшої популярності в різних побутових та промислових застосуваннях завдяки своїм чудовим характеристикам у порівнянні зі звичайними електродвигунами. Мета. СДПМ, спроєктований на основі вибору різних конструктивних змінних та оптимізований для їх виконання. Будучи чудовим у порівнянні з іншими двигунами, СДПМ має головний недолік: вищий крутний момент. Вищий крутний момент викликає пульсації крутного моменту в двигуні з постійними магнітами, що призводить до різних проблем, таких як вібрація, напруга ротора і шумна робота під час запуску і режиму. Проєктувальник повинен прагнути зменшити крутний момент зубчастого колеса на стадії проєктування для підвищення загальної продуктивності. Методи. Розроблено СДПМ з внутрішнім ротором v-подібної форми та стрижневого типу, та аналіз його характеристик виконаний з використанням аналізу методом скінченних елементів (FEA). Кут v-подібного магніту оптимізовано з метою зниження зубчастого моменту. Порівняння продуктивності здійснюється між оптимізованим двигуном та двигуном, спочатку спроєктованим за допомогою FEA. Новизна. Аналіз кута v-подібного магніту виконується таким же чином, зберігаючи решту всіх параметрів постійними, щоб отримати мінімальний зубчастий крутний момент. Запропонований спосіб практично життєздатний, оскільки не вимагає додаткових витрат та складності виготовлення. Практична цінність. Помічено, що v-подібний кут магніту є ефективним способом зниження зубчастого моменту. Зубчастий крутний момент зменшений з 0,554 Н×м до 0,452 Н×м за рахунок застосування методу оптимізації v-подібного кута магніту

Non-monotonic size dependence of the elastic modulus of nanocrystalline ZnO embedded in a nanocrystalline silver matrix

We present the first high pressure Raman study on nanocrystalline ZnO films with different average crystallite sizes. The problem of low Raman signals from nano sized particles was overcome by forming a nanocomposite of Ag and ZnO nanoparticles. The presence of the nanodispersed Ag particles leads to a substantial surface enhancement of the Raman signal from ZnO. We find that the elastic modulus of nanocrystalline ZnO shows a non-monotonic dependence on the crystallite size. We suggest that the non-monotonicity arises from an interplay between the elastic properties of the individual grains and the intergranular region.Comment: 10 pages, 6 figure

AN IN SILICO ANALYSIS OF FOLLICULIN AND FOLLICULIN INTERACTING PROTEINS RESPONSIBLE FOR SKIN TUMORS AND BIRT HOGG DUBÉ SYNDROME.

Birt–Hogg–Dube´ (BHD) syndrome is an inherited and autosomal disease characterized by skin and kidney tumors, as well as cystic lung disease, which results from mutation in BHD gene / FLCN gene. The product of FLCN gene is folliculin protein which has been implicated in numerous signalling pathways like mTOR, AMPK signalling, HIF signalling, TGF-β signalling and the JAK-STAT signalling pathway. From literature it was clear that there were two major consequences of mutated folliculin. First is hindrance in formation of FLCN, FNIP1 and FNIP2 complex, which ultimately interacts with TGF-β protein of TGF-β signalling pathway and inactivates tumor suppression function of that pathway. The other major consequence is activation of HIF1A. From HIF-reporter cell-based screening studies of a natural product-like chemical library it is suggested that KC7F2 is an inhibitor of HIF1A. Thus here we have focused on another inducible factor HIF2A interaction with KC7F2 to carry out insilico analysis. A previous study also suggests ability of TSA to reverse the biological and molecular defects of BHD cells but they have also suggested that further work will be needed to elucidate the nature of these effects. So we have carried out the work to study the nature of these effects and the mode of interaction between TSA and TGF-β protein. We found that TSA binds with TGF-β protein at same site where the non-mutated folliculin protein was binding and thus the TGF-β protein works normally, as a result anti-proliferation will takes place via p15 protein and ultimately the tumor suppression will takes place

Biomolecule surface patterning may enhance membrane association

Under dehydration conditions, amphipathic Late Embryogenesis Abundant (LEA) proteins fold spontaneously from a random conformation into alpha-helical structures and this transition is promoted by the presence of membranes. To gain insight into the thermodynamics of membrane association we model the resulting alpha-helical structures as infinite rigid cylinders patterned with hydrophobic and hydrophilic stripes oriented parallel to their axis. Statistical thermodynamic calculations using Single Chain Mean Field (SCMF) theory show that the relative thickness of the stripes controls the free energy of interaction of the alpha-helices with a phospholipid bilayer, as does the bilayer structure and the depth of the equilibrium penetration of the cylinders into the bilayer. The results may suggest the optimal thickness of the stripes to mimic the association of such protein with membranes.Comment: Published in ACS Nano http://pubs.acs.org/doi/pdf/10.1021/nn204736

Lentiviral Gene Transfer Corrects Immune Abnormalities in XIAP Deficiency

BACKGROUND: X-linked inhibitor of apoptosis protein (XIAP) deficiency is a severe immunodeficiency with clinical features including hemophagocytic lymphohistiocytosis (HLH) and inflammatory bowel disease (IBD) due to defective NOD2 responses. Management includes immunomodulatory therapies and hematopoietic stem cell transplant (HSCT). However, this cohort is particularly susceptible to the chemotherapeutic regimens and acutely affected by graft-vs-host disease (GvHD), driving poor long-term survival in transplanted patients. Autologous HSC gene therapy could offer an alternative treatment option and would abrogate the risks of alloreactivity. METHODS: Hematopoietic progenitor (Lin-ve) cells from XIAPy/- mice were transduced with a lentiviral vector encoding human XIAP cDNA before transplantation into irradiated XIAP y/- recipients. After 12 weeks animals were challenged with the dectin-1 ligand curdlan and recovery of innate immune function was evaluated though analysis of inflammatory cytokines, body weight, and splenomegaly. XIAP patient-derived CD14+ monocytes were transduced with the same vector and functional recovery was demonstrated using in vitro L18-MDP/NOD2 assays. RESULTS: In treated XIAPy/- mice, ~40% engraftment of gene-corrected Lin-ve cells led to significant recovery of weight loss, splenomegaly, and inflammatory cytokine responses to curdlan, comparable to wild-type mice. Serum IL-6, IL-10, MCP-1, and TNF were significantly reduced 2-h post-curdlan administration in non-corrected XIAPy/- mice compared to wild-type and gene-corrected animals. Appropriate reduction of inflammatory responses was observed in gene-corrected mice, whereas non-corrected mice developed an inflammatory profile 9 days post-curdlan challenge. In gene-corrected patient CD14+ monocytes, TNF responses were restored following NOD2 activation with L18-MDP. CONCLUSION: Gene correction of HSCs recovers XIAP-dependent immune defects and could offer a treatment option for patients with XIAP deficiency

Innovative Design Education in a Global Distance Learning Setting

A lot has been written about how much the world has changed since the advent of Globalization and that engineering education, in response to that needs to be addressed from a more holistic point of view. In this paper, we present an innovative approach to design education that represents a transformation from traditional in-class education to a globally distributed collaborative distance learning setting that mirrors real-world design experience

Educating Engineers for the Near Tomorrow

In this paper, we present an educational approach to facilitate Learning how to Learn, that is, to equip our students with competencies needed to become lifelong learners and succeed in the job market of the near tomorrow. Our approach is anchored in educational and instructional theory and closely tied to current professional practice. The approach is implemented in a graduate level engineering design course that is offered in a distributed collaborative distance learning setting

Evolving MRSA : high-level β-lactam resistance in Staphylococcus aureus is associated with RNA Polymerase alterations and fine tuning of gene expression

Most clinical MRSA (methicillin-resistant S. aureus) isolates exhibit low-level β-lactam resistance (oxacillin MIC 2–4 μg/ml) due to the acquisition of a novel penicillin binding protein (PBP2A), encoded by mecA. However, strains can evolve high-level resistance (oxacillin MIC ≥256 μg/ml) by an unknown mechanism. Here we have developed a robust system to explore the basis of the evolution of high-level resistance by inserting mecA into the chromosome of the methicillin-sensitive S. aureus SH1000. Low-level mecA-dependent oxacillin resistance was associated with increased expression of anaerobic respiratory and fermentative genes. High-level resistant derivatives had acquired mutations in either rpoB (RNA polymerase subunit β) or rpoC (RNA polymerase subunit β’) and these mutations were shown to be responsible for the observed resistance phenotype. Analysis of rpoB and rpoC mutants revealed decreased growth rates in the absence of antibiotic, and alterations to, transcription elongation. The rpoB and rpoC mutations resulted in decreased expression to parental levels, of anaerobic respiratory and fermentative genes and specific upregulation of 11 genes including mecA. There was however no direct correlation between resistance and the amount of PBP2A. A mutational analysis of the differentially expressed genes revealed that a member of the S. aureus Type VII secretion system is required for high level resistance. Interestingly, the genomes of two of the high level resistant evolved strains also contained missense mutations in this same locus. Finally, the set of genetically matched strains revealed that high level antibiotic resistance does not incur a significant fitness cost during pathogenesis. Our analysis demonstrates the complex interplay between antibiotic resistance mechanisms and core cell physiology, providing new insight into how such important resistance properties evolve