Metamorphism of cordierite gneisses from Eastern Ghat Granulite Terrain, Andhra Pradesh, South India

Cordierite-bearing metapelites of the Eastern Ghat granulite terrain occur in close association of Khondalites, quartzites, calc-silicate rocks and charnockites. Rocks occurring between Bobbili in the north and Guntur in the south of Andhra Pradesh are studied. The association of the mineral and textural relationships suggest the following metamorphic reactions: Garnet + sillimanite + quartz = cordierite, hypersthene + sillimanite + quartz = cordierite, sillimanite + spinel = cordierite + corundum, and biotite + quartz + sillimanite = cordierite + K=feldspar. Generally the minerals are not chemically zoned except garnet-biotite showing zoning when they come in close contact with one another. The potential thermometers are provided by the Fe-Mg distribution of coexisting biotite-garnet and cordierite-garnet. Conflicting interpretation of the P/T dependence of these reactions involving cordierite are due to H2O in the cordierite. The presence of alkali feldspar-quartz assemblage which is common in these gneisses will be constrained from melting only if H2O activity is less than 0.5. The piezometric array inferred is convex towards the temperature array, indicating a rapid and isothermal crustal uplift probably aided by thrust tectonics

Cross leg flaps: are they relevant in the present era?

Background: Injuries of lower limb due to road traffic accidents are challenging to reconstruct due to paucity of tissues and damage to vasculature. Recurrent trophic ulcers are also difficult to reconstruct due to stigmata of previous surgeries. When local and regional flaps are not available, free flaps become the best option. The success of free flap depends on the presence of healthy recipient vessels and microsurgical expertise. In cases where the free flaps have failed or when there is no available soft tissue for local flaps, cross leg flaps are a method of resurfacing and salvaging the limb.Methods: This Study was done from January 2013 to January 2016 in Rajiv Gandhi Government General Hospital, Chennai. 20 patients were included in the study and the flaps used were conventional cross leg and cross leg reverse superficial sural artery flap.Results: All flaps survived. There was one case of wound dehiscence managed by re-insetting, two cases with marginal necrosis which were managed conservatively. One case of partial loss which was managed by STSG and one case of sinus formation due to tuberculosis managed with ATT. Remaining flaps had no complications.Conclusions: Cross leg flaps are still relevant in the present era of microsurgery. They can be the primary choice of reconstruction or as a workhorse when free flaps have failed or other loco regional flaps are already exhausted. Immobilisation and two stage reconstruction are few disadvantages which when weighed against limb salvage are acceptable.

Thermodynamic Consistency of Plate and Shell Mathematical Models in the Context of Classical and Non-Classical Continuum Mechanics and a Thermodynamically Consistent New Thermoelastic Formulation

Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived using the conservation and balance laws of continuum mechanics in conjunction with the corresponding kinematic assumptions. This is referred to as thermodynamic consistency of the mathematical models. Thermodynamic consistency ensures thermodynamic equilibrium during the evolution of the deformation. When the mathematical models are thermodynamically consistent, the second law of thermodynamics facilitates consistent derivations of constitutive theories in the presence of dissipation and memory mechanisms. This is the main motivation for the work presented in this paper. In the currently used mathematical models for plates/shells based on the assumed kinematic relations, energy functional is constructed over the volume consisting of kinetic energy, strain energy and the potential energy of the loads. The Euler’s equations derived from the first variation of the energy functional for arbitrary length when set to zero yield the mathematical model(s) for the deforming plates/shells. Alternatively, principle of virtual work can also be used to derive the same mathematical model(s). For linear elastic reversible deformation physics with small deformation and small strain, these two approaches, based on energy functional and the principle of virtual work, yield the same mathematical models. These mathematical models hold for reversible mechanical deformation. In this paper, we examine whether the currently used plate/shell mathematical models with the corresponding kinematic assumptions can be derived using the conservation and balance laws of classical or non-classical continuum mechanics. The mathematical models based on Kirchhoff hypothesis (classical plate theory, CPT) and first order shear deformation theory (FSDT) that are representative of most mathematical models for plates/shells are investigated in this paper for their thermodynamic consistency. This is followed by the details of a general and higher order thermodynamically consistent plate/shell thermoelastic mathematical model that is free of a priori consideration of kinematic assumptions and remains valid for very thin as well as thick plates/shells with comprehensive nonlinear constitutive theories based on integrity. Model problem studies are presented for small deformation behavior of linear elastic plates in the absence of thermal effects and the results are compared with CPT and FSDT mathematical models

A study to analyse the presentation, treatment, Risk factors and outcome of patients with Obstructive and perforative colo –rectal Carcinoma

INTRODUCTION: Colo – rectal cancers ( CRC ) are the 3rd most cause of cancer death in developed countries. One third of the cancers are in rectum and two thirds are in the colon .Burden of the disease is similar in both men and women. Acute presentation of CRC Is more common. Can present as either Acute Intestinal obstruction, perforative peritonitis or both. Screening by colonoscopy helps in diagnosing and staging the cancer before complications develop. Prognosis is poor in patients presenting as complicated colo – rectal cancers. AIM OF THE STUDY : 1. To analyse the presentation , treatment and Outcome of patients with complicated colorectal Cancer (obstruction/perforation). 2.to evaluate the risk factors for morbidity and mortality. METHODOLOGY : Source of Data : Data was collected from the patients who got admitted in The Government Rajaji Hospital , Madurai from June 2012 to June 2014, with acute intestinal obstruction perforative peritonitis . The clinical study of obstructive and perforative colo-rectal carcinomas was conducted by selecting 30 patients, who got admitted in Government Rajaji Hospital , Madurai with Complicated Colo-Rectal Cancer presenting as acute intestinal obstruction and perforative peritonitis from June 2012 to June 2014. The institution where the study was conducted was well equipped to carry out all necessary investigations which helped in diagnosing and treating the cases. Inclusion Criteria: 1. Patients admitted with Acute Intestinal Obstruction or Perforative Peritonitis, and who also underwent surgery for the same problem and diagnosed as a case of Complicated Colo –Rectal Cancer were included in this study . Exclusion Criteria: • Patients without surgical management, • Familial polyposis, • Surgery done at an outside hospital, • Ulcerative colitis ,Crohn’s disease, • Patients with uncertain clinical diagnosis or insufficient clinical data. Mode of Selection : This study included all the patients admitted in general Surgery Wards of Government Rajaji Hospital, Madurai from June 2012 to June 2014 with acute intestinal obstrsuction and perforative peritonitis and also underwent surgical procedure for the same problem and were diagnosed be cases of Complicated Colo – Rectal Cancer. Information regarding age, sex, residence, significant Illness, physiologic status, risk factors, indications of surgery, tumour location, type of operation and tumour stage was recorded. All the data collected were retrospectively reviewed. SUMMARY: COLORECTAL CARCINOMA oocurs most commonly in males , when compared to females . COMPLICATED COLORECTAL CARCINOMA (CRC with obstruction and perforation ) is also found to be more common in males. Meat consumption , smoking and alcohol were found to be major risk factors associated with incidence of colo – rectal cancers . The incidence of obstruction and perforation in colorectal carcinoma is found to be more common in elder age group ( age > 60 years ).All the affected individuals are found to be mostly residing in rural areas. The common mode of presentation of complicated colo rectal cancers is found to be acute intestinal obstruction ( 80 % ). The most common site of location of the tumour is found to be sigmoid colon . Perforation is also very common in the site proximal to the tumour in sigmoid colon .Obstruction and perforation were found to be more common in left side colonic cancers .Sigmoid colon was also found to be the most common site for perforation . For colonic cancers presenting with obstructing and perforative peritonitis, Colostomy was found to be the most commonly performed procedure. Due to Unprepared bowel and poor general condition of patient , resection and anastomosis was not commonly performed .For obstructive cancers mostly resection and primary anastomosis was performed. Acute presentations of colo –rectal cancers were most commonly found in patients with advanced disease ( stage III & stage IV ).Comorbid illness like Diabetes ,Hypertension ,COPD and Renal problems were found to have influence on the outcome of patients with colo – rectal cancers. Most common major complications were found to be sepsis, muti organ failure and respiratory failure . Above given complications were major reasons for the moratility of the patients. Among the patients who underwent surgery ,few minor complications occurred, among which more common was abdominal wound infections and wound dehiscence. Complicated colo – rectal cancers presenting as acute obstruction or perforative peritonitis is most common in males.Perforative colo- rectal cancers are more common in females. - Common age group affected is > 6o years of age . - Most of the patients presenting as acute emergencies are from rural areas. - Complicated colo –rectal cancers are most commonly associated with smoking ,alcohol intake , meat consumption .These factors are found to be present in patients presenting with advanced disease with complications. - Complicated colo – rectal cancers most commonly present as acute intestinal obstruction. - Left colon , more commonly sigmoid colon is found be affected in both obstructive and perforative colo – rectal cancers . - Majority of the patients are found to have advanced tumour (STAGE III & STAGE IV) -Colostomy is the most commonly performed procedure . -Sepsis , renal and respiratory problems are the major complications responsible for morbidity and mortality

Characterisation and Response to Beneficiation of Ferruginous Chromite Ores

Sukinda-Nausahi belt of Orissa, represent about 90% of the Indian Chromite ore reserves. These ores are later-itic type in nature resulted by weathering of ultrabasic rocks, Metallurgical industries consume maximum chromite ores- around 50% followed by refractory and chemical indu-stries which consume about 35% and 15% respectively. The utility pattern of chromite in industries is varying greatly. The variation in the demand could be due to lim-ited market for medium and low grade chromite. Hence it is necessary to improve the chromium content for better util-isation and conservation of available resources

Design and Modeling of Tool Trajectory in C0 Continuity Concept by Importing the IGES Neutral File

A common task in geometric modeling is to interpolate a sequence of points or derivatives, sampled from a curve, with a parametric polynomial or spline curve. To do this the first step is to choose parameter values corresponding to the interpolation points. In a parametric environment, user can completely define a geometric feature with some parameters. This paper has an aim to generate a smooth tool trajectory spline for machining a workpiece. With the spline technique MATLAB program has been proposed for simulation of cutter contact points in the trajectory. The author has gone through C0 continuity concept and at last the simulated result has been shown by MATLAB program in its output. Keywords: Spline, Approximation technique, C++, IGES, MATLA