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The growing intensive aquaculture system around the world maintains a high stocking density, wherein it is essential to increase and sustain the optimum dissolved oxygen concentration (DO) through the provision of artificial aeration systems. The selection of an aerator is a crucial aspect of aquaculture operations. The selected aerator must be economically efficient and should be able to fulfill the requirement of oxygen supply in the pond water. The present study provides an extensive literature review on the importance of artificial aeration in aquaculture, the standard method of test for performance evaluation of an aerator, various aeration systems and their mechanisms, method to determine the numbers of aerator requirement, comparative studies of different type of aerators, and economic consideration in selection of aerators. In addition, a thorough analysis has been done to suggest the type of aerator that is economically viable and efficient for different pond volumes based on the performance data reported in the reviews. Therefore, this study may help the end-users (fish farmers) to select the best aerator based on their requirements.

In the present study, an improvised design over circular stepped cascade (CSC) and pooled circular stepped cascade (PCSC) aerator, named the perforated pooled circular stepped cascade (PPCSC) aerator, has been conceptualized and tested for its suitability as an aerator for small intensive aquaculture ponds. Based on dimensional analysis, dimensionless geometric parameters – ratio of width of consecutive steps (Wi/Wi+1) and ratio of perforation diameter to bottom-most radius (d/Rb) and dimensionless dynamic parameters – Froude (Fr) and Reynolds (Re) number were proposed. Initially, aeration experiments were conducted to optimize the geometric parameters, keeping the dynamic parameters constant. Keeping the optimized values of Wi/Wi+1 = 1.05 and d/Rb = 0.0027 as constants, aeration experiments were further conducted at different discharges (Q) and different bottommost radius (Rb) to study the characteristics of oxygen transfer and power consumption of PPCSC aerator at different dynamic conditions. Based on the optimized results, four prototype PPCSC aerators with Rb = 0.75 m, 0.90 m, 1.05 m and 1.20 m were fabricated for their aeration performances. The results showed that the standard aeration efficiency (SAE) values of the prototype PPCSC aerators based on brake power ranged between 3.36 and 4.98 kg O2/kWh, with the average being 4.45 ± 0.741 kg O2/kWh. This shows that the SAE of the PPCSC aerator is many more folds higher than that of the other available cascade aerators, viz., PCSC (SAE: 2.873 ± 0.342 kg O2/kWh) and CSC (2.470 ± 0.256 kg O2/kWh) aerators. The study clearly indicates that this PPCSC aerator may very well be used as pre-aeration or post-aeration units in water or wastewater treatment plants and small-scale intensive aquacultural ponds, replacing the other existing aerators.

Selection of aerator is a very important aspect in aquaculture operations. The selected aerator must be economically efficient and should be able to fulfil the requirement of oxygen supply in the pond water. In the present study, economic feasibility of nine different types of aerators, namely, perforated pooled circular stepped cascade (PPCSC), pooled circular stepped cascade (PCSC), circular stepped cascade (CSC), paddle wheel (PWA), spiral aerator (SA), propeller-aspirator-pump (PAA), submersible (SUBA), impeller aerator (IA) and air-jet aerator (AJA) was assessed based on capitalization method, a life cycle costing (LCC) approach. The results revealed that the PPCSC aerator can be considered as the most suitable aerator when dissolved oxygen (DO) content in the pond water is less than equal to 3 mg/L, and pond water volume (V) is less than 2100 m3. In other situations, mostly when pond water volume is more, IA proves to be the most suitable aerator, followed by PWA, PPCSC, and other available aerators. The sensitivity analysis conducted by using varying stocking density and capital cost also showed the same trend with regard to selection of aerators. This life cycle costing approach for selection of aerator can be implemented for any types of cultured species at any prevailing environmental conditions.

There are different admission tests around the world exclusively for admission to dental schools. NEET National Eligibility cum Entrance Test (NEET) is a multiple choice entrance exam in India for medical, dental as well as paramedical courses, including nursing, physical therapy, pharmacy, and occupational therapy. There is no exclusive test only for dental admissions. There is no scientific literature on NEET and its effects on students, parents as well as the teaching faculty. Though there are a lot of news articles and blogs about it. There is no evidence on how the staff of dental fraternity perceived this change in admissions of students to dental colleges. There has been significant controversy around this change in the admission process. The aim of this survey is to understand the perspective of the dental teaching faculty about NEET, the admission procedure, the difference in the quality of students and the type of the questions in the exam.

Aim: To evaluate oral health awareness among the general population.Background: According to WHO, the prevalence of periodontitis, dental caries, leukoplakia, OSMF are 86%, 68%, 0.59% and 0.55% respectively in India. Habits in Indian population like smoking and alcohol is also a cause for bad oral health at a prevalence of 15.02% and 8.78% respectively. Dental care can sometimes be a forgotten part of a healthy life style. While its importance is often underestimated, the need for regular dental care cannot be overstated. Oral health has been neglected for long in India. Materials and Methods: A total of 150 people in the age group 15-70 years were selected using random sampling technique. A self-administered structured questionnaire including 13multiple choice questions was given to them. The results were analyzed. Result: In the present study, questionnaire was distributed to 150 patients who were randomly selected in that only 101 participants were interested to take part in it. Only 37.62% of participants brushes twice daily, rest of them brushes only once a day. Cleansing method has been improved,82.17% uses tooth brush and paste to clean their teeth. About 13% of participants where aware about the interdental aids out of which 11% used floss and 2% used interdental brush, 70.39% participants uses tongue cleaner regularly and only 30%uses mouth wash. The results of this study suggest that oral health awareness and practices among the study population are improved when compared with the pervious studies but still there is lack of awareness thus need to be improved. Conclusion: The above-mentioned oral hygiene problems can be prevented by simply providing awareness, which is a more cost- effective alternative than expensive dental procedures. Dental professionals, Dental Marketing Agencies, and media too may join hands with the government to help in the prevention of oral health problems by improving knowledge, attitudes, behaviors, and practices toward oral hygiene among the general population.

A parametric evaluation of elliptical pin fin heat sinks was performed using a commercially available CFD software package. The investigation involved variation of fin length, fin height, fin gap width, and air velocity while holding the heat flux and fin geometry as constants. The effect of these variables on the thermal performance and airflow impedance characteristics of the heat sink was studied and an optimum heat sink design was selected for a given set of conditions. Additionally, an often-encountered user requirement of multiple heat sinks in a row was also studied with these variables. In line and staggered elliptical fins as well as plate or extruded fins were analyzed although the main focus of the evaluation was based upon in line elliptical fins.Copyright © 2003 by ASME