UNUSUAL THERMAL TRANSPORT IN GRAPHENE / BORON NITRIDE SINGLE INTERFACE & SUPERLATTICE TUNED BY INTERFACIAL ROUGHNESS

Graphene combined with Boron Nitride is a superlattice that has a lot of potential in terms of tenability. There has been a lot of work that has gone into finding ways to tune the properties of this superlattice to improve its figure of merit. Interfacial roughness if strategically induced is thought to have the potential to increase the thermal conductivity without sacrificing any of the qualities of the superlattice. We perform equilibrium molecular dynamics via Green Kubo method on Graphene/Boron Nitride and study its thermal conductivity under the influence of various parameters that shape the superlattice and its properties. Green Kubo method involves generating the lattice structure and using a pair potential along with boundary conditions to implement equilibrium molecular dynamics. The simulation give us a heat current auto-correlation function (HCACF) which can be used to find the thermal conductivity of the system

A Diachronic Hypothesis about Imperfective unnu in Malayalam

Across languages, the imperfective is associated with three distinct readings－“event in progress”, “habitual or generic” and “continuous” with stative predicates. In Malayalam, the suffix unnu had been identified as the imperfective suffix in linguistic literature. However, it has been noted in subsequent studies that the “generic or habitual” reading with unnu is distinctly different from a typical generic reading and that such ‘typical generic’ readings are obtained by the modal um in Malayalam. This has also led to the claim that unnu is not an imperfective marker, but an iterative pluractional bundled with progressive aspect. This paper attempts to deal with this puzzle differently, arguing that unnu is a progressive marker in the process of becoming an imperfective in Malayalam. A description of the properties of unnu-sentences, contrasting them with sentences that use the progressive marker uka and sentences that use the modal/generic marker um, is attempted. The paper also explores the role of uND(ə), the existential copula, in obtaining habitual and episodic readings with unnu. This alternative account for unnu is shown to be supported by opinions of traditional grammarians in history as well as theories of grammaticalization in diachronic semantics. It is also hypothesized that this process is blocked or halted in Malayalam by a suffix devoted to generic constructions and previously unexplored in the literature

Micro-fabrication of bio-MEMS based force sensor to measure the force response of living cells

Understanding how a living cell behaves has become a very important topic in today’s research field. Hence, different sensors and testing devices have been designed to test the mechanical properties of these living cells. This thesis presents a method of micro-fabricating a bio-MEMS based force sensor which is used to measure the force response of living cells. Initially, the basic concepts of MEMS have been discussed and the different micro-fabrication techniques used to manufacture various MEMS devices have been described. There have been many MEMS based devices manufactured and employed for testing many nano-materials and bio-materials. Each of the MEMS based devices described in this thesis use a novel concept of testing the specimens. The different specimens tested are nano-tubes, nano-wires, thin film membranes and biological living cells. Hence, these different devices used for material testing and cell mechanics have been explained. The micro-fabrication techniques used to fabricate this force sensor has been described and the experiments preformed to successfully characterize each step in the fabrication have been explained. The fabrication of this force sensor is based on the facilities available at Michigan Technological University. There are some interesting and uncommon concepts in MEMS which have been observed during this fabrication. These concepts in MEMS which have been observed are shown in multiple SEM images

Deep soft-tissue leiomyoma of the forearm mimicking a primary bone tumor of the ulna

AbstractLeiomyomas of the soft tissues are rare in general, and extremely uncommon in the forearm. In general, leiomyomas are benign soft-tissue tumors that occur where smooth muscles are present. We present a case of soft-tissue leiomyoma of the forearm eroding the midshaft of the ulna, with emphasis on radiological diagnosis and histopathological correlation

Factors predicting survival after pancreaticoduodenectomy for periampullary carcinoma - A Retrospective analysis.

INTRODUCTION : Carcinoma of periampullary region accounts for 85% of pancreaticoduodenectomies at our institute. Tumours of ampulla of vater are relatively rare, with an crude incidence rate of 0.53 /1,00,000 population per year. Overall periampullary cancers account for 5 % of all gastrointestinal tract malignancies. A periampullary carcinoma – one arising in the region of ampulla of vater , may be from one of four potential origins- pancreas ,bile duct, the ampulla itself or periampullary duodenum. Surgical series of periampullary tumors have demonstrated that patients with ampullary tumors have a more favourable prognosis than those with pancreatic or bile duct tumors with median survivals of 30 to 50 months and 5-year survival rates between 30% and 50%. Lymph node metastasis and vascular invasion were found to be independent factors adversely influencing survival in an Indian study. Studies attempting to determine important factors affecting survival have been limited by several factors..Most contain small numbers of patients collected over many decades & many do not use multivariate analysis to identify independent prognostic factors. Furthermore , most studies do not assess preoperative factors such as age or biochemical variables. AIMS & OBJECTIVES : 1. To analyse factors influencing survival in a series of patients with periampullary tumours who underwent pancreaticoduodenectomy in a single tertiary referral unit . 2. To examine the results of resection & its impact on clinical outcomes on various typesof carcinomas including Ampullary carcinoma,distal Cholangiocarcinoma & Duodenal Carcinoma. MATERIALS AND METHODS : Pooled data from patients undergoing pancreaticoduodenectomy for periampullary carcinoma over a 13 year period from 1995 to 2008 was retrospectively evaluated and analysed. Included in this study were 69 consecutive cases of nonpancreatic periampullary carcinomas ,which during final histological examination proved to be ampullary, cholangial or duodenal origin. All patients had adenocarcinoma of periampullary region. All patients underwent evaluation and treatment at our institute between 1995 to 2008. Patients with benign pathologies, neuroendocrine tumours and carcinoma of head of pancreas who underwent pancreaticoduodenectomy were excluded from this study. All patients underwent thorough clinical examination. Routine hemogram, renal function test, liver function test, chest x ray, electrocardiogram were done for all patients. USG Abdomen & pelvis ,CT abdomen & pelvis were done as part of staging evaluation. ERCP and stenting were done in selected patients either done outside or at our institute. CONCLUSION : Preoperative bilirubin , nodal involvement and Lymphovascular invasion are important predictors of survival in those who undergo resection of non pancreatic periampullary carcinoma. Ampullary tumours have a good prognosis, as they are often resectable .The acceptable morbidity rate among resected patients , support an aggressive surgical approach to the management of ampullary tumours