Aluminum Alloys Behavior during Forming

Industrial revolution toward weight reduction and fuel efficiency of the automotive and aerospace vehicles is the major concern to replace heavy metals with light weight metals without affecting much strength. For this, aluminum alloys are the major contributors to those industries. Moreover, aluminum alloys are majorly categorized as 1xxx, 2xxx, 3xxx, 4xxx, 5xxx, 6xxx, 7xxx, and 8xxx based on major alloying elements. Among all, 2xxx, 5xxx, 6xxx, and 7xxx are having majority of applications in the abovementioned industries. For manufacturing any engineering deformable components, forming characteristics are must. Forming behavior of aluminum alloys has been evaluated through different processes including deep drawing, stretching, incremental forming, bending, hydro forming etc., under different process conditions (cold, warm, and hot conditions) and process parameters. Each process has its own process feasibility to evaluate the formability without any forming defects in products. The present chapter discusses a few important processes and their parameter effect on the aluminum alloys through the experimentations and simulation works

TARBP2 -Mediated Post-Transcriptional Regulation of Gene Expression During Murine Embryonic Development and Spermatogenesis

Micro RNAs (miRNAs), which are ~22 nucleotide (nt) long RNA molecules and several RNA binding proteins (RBPs) engage in an RNA dependent post-transcriptional gene silencing process known as RNA interference (RNAi). In the canonical miRNA biogenesis pathway, an enzyme known as DICER cleaves the ~70nt pre-miRNA to a ~22nt long miRNA that is loaded into the RNAi effector mechanism, the RNA induced silencing complex (RISC). Several in vitro studies provide suggestive evidence that mammalian double stranded RNA binding proteins (dsRBPs), such as TARBP2, act as DICER cofactors in miRNA processing and RISC loading to promote RNAi activity. A screen attempting to identify translational regulators of the murine Protamine1 gene identified TARBP2 as a potential translation regulator. It is unknown if TARBP2 has a role in miRNA biogenesis in vivo, or if the translation regulation of Prm1 during murine spermatogenesis is dependent on TARBP2 mediated miRNA biogenesis. Murine embryos with a constitutive null allele of Tarbp2 and adult mice with a germ cell-specific loss of TARBP2 were generated to lead to understanding of the role of TARBP2 in miRNA biogenesis and TARBP2 mediated post-transcriptional gene regulation during spermatogenesis. Here, I describe that TARBP2 regulate biogenesis of a sub-set of miRNAs during murine embryonic development and spermatogenesis. Also, the role of TARBP2 dependent miRNAs in post-transcriptional regulation of gene expression during murine spermatogenesis will be discussed

A study of surgical management of distal femoral fractures in adults using locking compression plate

Background: The introduction of locking compression plates with option of locked screws has provided the means to increase the stability of fracture fixation.Methods: In this study, 30 distal femoral fractures were treated using the distal femoral locking compression plate. All fractures were fresh, closed and operated within 12 days. Follow up duration ranged from 6 to 18 months.Results: In this study, 20 patients were males and 10 were females. The 23 of the fractures (76.66%), were caused by road traffic accidents, 3 were due to accidental falls (10%), one was due to assault and 3 were due to fall from height.9 patients had associated injuries.  All patients were treated with open reduction and internal fixation using Locking Compression Plate. 6 to 9 holed plates were used. Out of 30 patients 2 went for delayed union and 3 went for non-union. Average knee flexion was 109o having knee range of motion more than 100 with 50% patients. Average knee extensor lag was 2.4 degrees with only 4 patients with lag more than 5. 2 patients developed 2 cm shortening. 4 patients had less than 5 degrees of malalignment. 2 patients had deep infection. Functional outcome was measured using NEER's scoring system and was done at the end of 5- 7 months (average of 6 months).  Excellent results- 17 (56.66%) good results-8 (26.66%) fair results-2 (6.66%) poor results-3 (10%).Conclusions: LCP condylar plate represents an evolutionary approach to the surgical management and is an important armamentarium in distal femur fracture fixation, especially when fracture is severely comminuted and in situations of osteoporosis.

Reasoning with BDI robots: from simulation to physical environment – implementations and limitations

In this paper an overview of the state of research into cognitive robots is given. This is driven by insights arising from research that has moved from simulation to physical robots over the course of a number of sub-projects. A number of major issues arising from seminal research in the area are explored. In particular in the context of advances in the field of robotics and a slowly developing model of cognition and behaviour that is being mapped onto robot colonies. The work presented is ongoing but major themes such as the veracity of data and information, and their effect on robot control architectures are explored. A small number of case studies are presented where the theoretical framework has been used to implement control of physical robots. The limitations of the current research and the wider field of behavioral and cognitive robots are explored

Morphometric evaluation of the kidney and its main renal artery

Background: With the increasing incidence of renal transplantations and advent of modern imaging techniques in the current era, the knowledge of renal artery variations in their position of origin from abdominal aorta, level of origin from the superior mesenteric artery, pattern of their division towards the renal hilum, and the additional branches from the renal arteries should be well known for preparing renovascular surgical and radiological interventions.Methods: Fifty specimens from 25 adult human embalmed cadavers were taken from the department of anatomy and were studied by dissection method. Morphometric data of the specimens dissected were recorded using vernier calipers.Results: Though morphometric analysis of both the kidneys was studied, it shows no significance from earlier studies. Accessory renal arteries were noted in 24% of cases with equal incidence on both sides. Within accessory, hilar type was most common (14%), followed by inferior polar in 12% and superior polar in 2% of specimens. Accessories in 28.5% specimens gave rise to gonadal arteries and 7.3% specimens to inferior phrenic artery.Conclusion: The results suggest that there are a large number of anatomical variations in the vascularisation of the kidney. The most common incidence is the occurrence of accessory renal arteries. It was rarely found that superior and inferior polar arteries originated from the renal artery. The renal artery diameter is a factor which should be considered as predicting the presence of additional renal arteries.  

Blast optimisation with In Situ rock mass characterization by seismic profiling at an opencast coal mine in India

Blast optimisation studies were conducted at an opencast coal mine in India for selection of a site specific explosive for different rock types. This seismic refraction survey technique was applied at sandstone benches of a coal mine for rock mass characterisation and blast optimisation by impedance matching of explosives. Field experiments were conducted on seismic profiling to characterise sandstone rock mass on the basis of P-wave velocity (Vp) measurements. The running benches were selected for the experimentation so as to cross check the results of the Vp with the exposed faces of the benches. The instrument used for seismic profiling contains 24 geophones of 14 Hz frequency. The mode of survey was the „refraction method‟ which could give the Vp profile up to 50-60 m depth and about 100 m stretch. The source of vibration generation was by hammering of specific Sledge hammer. The raw seismic data collected in the field was analysed by a software called ‟Seismic imager‟ for generating a Vp profile of the rock strata. The Vp profiles were determined for three benches of the mine, which include weak, medium and hard type of rock mass. The rock impedance was calculated based on the Vp determined by seismic profiling. This data was used for the selection of explosive with desired velocity of detonation and density, so as to match the impedance of the rock mass. The blast performance with the suitable explosives with impedance matching was obviously better than that of impedance mismatching. Trials were also conducted with heave energy-rich ANFO explosive with mismatched impedance properties and observed better results. The optimisation studies resulted in reduction of back break by 50-75% and reduction of mean fragment size by 15-47%. The paper stresses the need for conducting impedance matching exercise for all the blast sites for blast optimisation and productivity improvement

Self-incompatibility system of Oenothera organensis for the detection of genetic effects at low radiation doses.

The self-incompatibility system of Oenothera organensis is used to analyze the frequency of S locus mutations induced by low doses (2.5-20 rad) of fast neutrons and x-rays. Th principles and methods of the screening system for detection of low dose effects have been presented. The results show that low doses induced significantly higher frequencies of seeds and seedlings than those produced spontaneously. The analyses of part of the progenies derived from the control and treated series suggested that they were due to revertible mutations. A modified in vitro method of culturing pollinated cut styles has been developed for rapid screening of compatible pollen tubes