Estimates for the pressure and thermal distortions of coating dies for use in design and simulation

A coating die is used for distributing liquid in order to apply a uniform film on a solid surface. The fluid flowing through the die cavity can exert a pressure of up to 500,000 Pascal on the die body. This liquid pressure can distort the die and lead to a non-uniform slot opening, which in turn causes non-uniformity in the coating thickness. Distortion of the die can also occur during non-isothermal operation of the die; this is an undesired consequence of delivering liquids at a different temperature than the die itself. The distortions undergone by the die both due to liquid pressure and non-isothermal conditions should be within the manufacturing tolerances for the slot heights in order to maintain uniformity in the coating. The deformation exhibited by a coating die due to pressure loadings is modeled both two-dimensionally and three-dimensionally. A two-dimensional model has lower computational load and is preferred for die design. For the two-dimensional analysis of a coating die, the finite element method is used to determine the deflections due to pressure loadings with a focus on slot heights. A model of low computational load is also developed based on beam theory, and its results are compared with those of the two-dimensional finite element analyses predictions. The beam model is incorporated in a die design and simulation program in which flow and slot deformations are coupled. Two-dimensional finite element analyses due to non-isothermal conditions are also performed on the coating die to give an estimate of the die deflection due to temperature variations within the die. A three-dimensional coating die with varying inner cavity area is modeled and analyzed to check its predictions with those of the two-dimensional finite element analyses and beam theory results. In the literature reviewed, flow distribution is fully coupled to die deformation only for extrusion dies. Extrusion dies are used for extruding melted polymers of very high viscosity. Therefore, the deflections are much larger for extrusion dies than for coating dies. Mechanical adjustments can be used to manage the large deflections in the case of extrusion dies whereas coating dies have to be designed for small deflections comparable to manufacturing tolerances. This is the first time where a coupled analysis has been done for a coating die. This research provides the slot deflections for a coating die subjected to pressure loadings that vary throughout the die length. The model of flow distribution coupled with die distortion incurs low computational load and is intended for use in design and simulation programs. Die design guidelines are developed based on examination of the die dimensions and flow parameters having the greatest effect on slot deflections

Benign cystic peritoneal mesothelioma

A well-defined but rare entity of Benign Cystic Peritoneal Mesothelioma (BCPM) is reported. The aetiology of this neoplasm remains obscure. The presenting features make a precise preoperative diagnosis difficult but information provided by computed tomography and cytology may help. A firm diagnosis can only come from an electronic microscopy or immunohistological examination of the tumour. Diagnostic accuracy and diligent follow up are essential because, although the tumour is considered benign, it does tend towards local recurrence

Antifungal Efficacy of Sodium Hypochlorite and Four Intracanal Medicaments: An in vitro Evaluation

Objective: To evaluate the effect of 2.5% sodium hypochlorite and four intracanal medications on Candida albicans harvested inside root canals. Materials and methods: The contaminated canals were irrigated with sterile saline and then treated as follows: filled with (1) calcium hydroxide and saline, (2) calcium hydroxide and 2% chlorhexidine gluconate, (3) zinc oxide and 2% chlorhexidine gluconate, (4) amphotericin B powder and distilled water, (5) irrigation with 2.5% sodium hypochlorite with no medication and (6) no intracanal medication. Canal access and apex were sealed with cavit and the roots were stored in an incubator at 37 ± 1°C for 14 days. The canals were reinstrumented and irrigated with saline. Sterile paper points were used to transfer the root canal contents to test tubes containing saline. Part of the suspension was harvested on Sabouraud dextrose agar with chloramphenicol and incubated at 37 ± 1°C for 48 hours. Results: Group 5 was effective in 90% of the samples and least effective was group 1 (50% effective). Conclusion: Within the limitations of this study, long-term intracanal medication was important to eliminate microorganisms especially Candida albicans present inside root canal.&nbsp

Influence of regular exercise on cardiac autonomic activity in. healthy young women during the normal menstrual cycle

ABSTRACT Regular physical exercise leads to considerable changes demonstrated in the increase of health related fitness. Heart rate variability is a measure of autonomic nervous system function. Gonadotropin hormones affect autonomic nervous system function. Regular exercise is thought to modulate the sympathovagal control of the heart leading to an enhancement of the vegetative control of the heart. The present study aims to describe the heart rate variability and assesses its association with regular exercise and menstrual cycle in healthy young women in frequency domain method in different phases of menstrual cycle. A total of 54 female students were selected. The selected students were divided into two groups namely Group I consisted of subjects doing regular physical exercise for 30 minute each day and Group II consisted of individuals who were non exercisers the ECG recording were taken during the 3 phases of menstrual cycle. The analog ECG signal were conveyed through an A/D converter to PC and were analyzed .The frequency domain analysis was done in which the LF, HF and LF/HF components were studied. Results showed that a significant increase in the LF/HF ratio in the luteal phase of menstrual cycle in the non exercisers group when compared to other phases of the menstrual cycle (P<0.001) . Regular exercisers had more parasympathetic activity than non exercisers. Detection of sympatho vagal inbalance at an early age based on regular exercising with necessary life style modification could decrease the incidence of cardiovascular diseases as age advances

OCCLUSION IN IMPLANT-AT A GLANCE

Objectives: Occlusion is a critical and very important component for the clinical success and longevity of dental implants. This review article focuses on the various aspects of implant protective occlusion. Our scientific literature regarding implant occlusion, particularly in implant-supported fixed dental prostheses remains controversial.Materials and methods: A search strategy was performed in MEDLINE/PubMed, Scopus and Google Scholar with keywords – ‘implants’ and ‘occlusion’, ‘implants’ and ‘fixed prosthesis, ‘implants’ and ‘fixed dental prostheses’, ‘implants’ and ‘partial edentulism’, ‘implants’ and ‘complications’, ‘implants’ and ‘failures’, ‘implants’ and ‘cantilever’, ‘implants’ and ‘occlusal load’.Results: 135 articles were retrieved. After hand search a total of 290 articles were identified. Ultimately, 30 articles were selected and summarized and discussed as they met the selection criteria.Conclusion: Most of the available clinical data are controversial. Implant-protected occlusion can be accomplished by decreasing the width of the occlusal table and improving the direction of force. By doing these things, we can minimize overload on bone-implant interfaces and implant prostheses, to maintain an implant load within the physiological limits of individualized occlusion, and ultimately provide long-term stability of implants and implant prostheses. Current clinical practices rely heavily on principles extracted from the natural dentition or removable dental prostheses on complete edentulous patients and on expert opinions

Clinico-epidemiological profile of malaria: Analysis from a primary health centre in Karnataka, Southern India

Malaria continues to be a major public health problem in India and worldwide. The present study was based on records from a primary health centre in Karnataka. Morbidity patterns and important features of malaria transmission specific to Udupi district were investigated. The incidence of malaria and various morbidity patterns during 2010 and 2011 were compared and analyzed. Factors such as rapid urbanization, increased construction activities and influx of migratory workers were highlighted as the leading causes for the advent of malaria in the area. Recommendations have been provided for implementation in the near future

COLORECTAL CANCER AND ITS RISK FACTORS AMONG PATIENTS ATTENDING A TERTIARY CARE HOSPITAL IN SOUTHERN KARNATAKA, INDIA

Objective: To determine the association between certain socio-demographic and life style factors with colorectal cancer.Methods: This case-control study was conducted using a pre-designed questionnaire among 100 incident colorectal cancer patients and 200 unmatched controls attending a tertiary care hospital in southern Karnataka. Cases and the controls were interviewed and details regarding their socio-demographic factors were collected. Information on lifestyle factors such as dietary habits, physical activity levels and substance use were documented. They were also assessed for presence of existing co-morbidities and family history of colorectal and other cancers. Multivariable logistic regression was performed to determine the association between various risk factors and colorectal cancer.Results: In the present hospital based study, mean age of the participants was less than 55 years. Sixty three percent of the cases and 54.5% of the controls were males. On multivariable analysis age ≥50years (OR=1.87; 95%CI=1.02-3.45), low physical activity (OR=5.66; 95%CI=3.10-10.34) and low frequency of fruits consumption (OR=4.10; 95%CI=2.21-7.50) and hypertension (OR= 4.65; 95% CI=1.32-16.44) showed a positive association with colorectal cancer.Conclusion: Promoting healthy dietary practices and physical activity among the middle aged population appears to be significant in the context of colorectal cancer prevention in the Indian subcontinent.Keywords: Colorectal cancer, Case–control, Risk factors, Lifestyle, Comorbidities

Evaluation of Preclinical Task Based Learning program in Medical Education [version 1; peer review: 1 approved, 2 approved with reservations]

The conventional curriculum in preclinical medical education has a need for early clinical exposure programs that help in correlation of basic science data with clinical skills. This is helpful to develop clinical reasoning skills, problem-solving abilities, team work, communication skills and overall attitudes and behaviour relevant for a healthcare provider. Preclinical task based learning (TskBL) is an active learning strategy in which the focus for the first year medical student is a real task done by a doctor. In this strategy the student-doctors undergo a standardized patient encounter and discuss the learning issues related to the task in the first year of medical school. The current study is focussed on the student perception of the effectiveness of task based learning module.The TskBL was conducted among first year medical students for nine topics that are commonly encountered in the clinics. After TskBL was planned and implemented the evaluation of the modules was done using focus group discussions. The students highlighted the importance of standardized patients in the TskBL strategy in providing early clinical exposure in preclinical medical education. They reported its usefulness gaining essential knowledge, skills and attitudes for medical learning. They reported positive outcomes of module design and processes and activities in TskBL. Based on the negative aspects of the modules, future improvement was suggested in improving the usefulness of standardized patient encounter. This study showed the novice learners’ outlook of the potency of TskBL for several other topics of clinical relevance to provide early clinical exposure in medical schools