Radiation and non-​Darcy effects on convection in porous media

Combined conduction , convection and radiation heat transfer in a gray fluid-​satd. sparsely packed porous medium is analyzed for the case of marginal convection by using linear stability anal. The effects of boundaries and inertia that are absent in the usual Darcy model are considered. The Milne-​Eddington approxn. is employed to det. the solns. valid for transparent and opaque media that absorb and emit thermal radiation. The nature of the bounding surfaces and radiation affect the crit. Rayleigh and wave nos. The mechanism for suppressing or augmenting convection is discussed. The results obtained by using the Galerkin technique are compared with the existing results of the Darcy model and of nonradiating systems, and agreement is found

Effect of radiative transfer on the onset of convection in a porous medium

The effect of radiative transfer on thermal convection of a thin fluid-saturated densely packed porous layer bounded by stress-free radiating horizontal planes heated from below is studied using linear theory. The coefficients of absorption, emission and scattering are computed from packed bed properties using a two-flux model. The Milne-Eddington approximation is employed to determine approximate solutions valid for optically thin (transparent) and optically thick (opaque) gray media which absorb and emit thermal radiation. The effect of radiation parameters on the cell size and on the onset of convection are studied in detail using the Galerkin approximation. It is shown that the effect of radiation is to inhibit the onset of convection in a porous medium. The physical explanation for this is given, taking into account the increase in thermal conductivity due to the combined effects of the porosity of the medium and radiation

Emerging small scale trap fishery for whelk, (Babylonia spirata) in Malpe, Southern Karnataka

Babylonia spirata is a commercially important edible gastropod found inhabiting the coastal waters with sandy bottom. Commonly known as whelks, they are landed as by-catch in shrimp trawlers in Kerala and Tamilnadu.There is an emerging fishery for whelks along the Malpe coast (13° 21’ N and 74°42’5” E) with the increase in export demand. Specially designed whelk traps are operated from traditional fishing crafts to collect whelks since January 2005

Phytochemical Screening and Antimicrobial Activity of the Plant Extracts of Mimosa pudica L. Against Selected Microbes

Mimosa pudica L. is a creeping annual or perennial herb. It has been identified as Lajjalu in Ayurveda and has been found to have antiasthmatic, aphrodisiac, analgesic and antidepressant. In the present study the active phytocomponents of Mimosa pudica were revealed using phytochemical analysis. The antimicrobial activity of Mimosa was studied using well diffusion method. The activity was tested against Aspergillus fumigatus, Citrobacter divergens and Klebsiella pneumonia at different concentrations of 50, 100 and 200μg/disc and the results have been illustrated

Cystic swellings of scrotum: Management

The cystic swellings of scrotum are one among the commonest clinical entities faced by a surgeon in day to day practice and a cause of concern to the patient more with his fertility. Presenting with varied etiology they can represent a wide range of medical issues. Gold standard for the management of such cystic swellings of scrotum continues to be surgical extirpation of the lesion. Objective: To identify the cause, mode of presentation, various modalities of treatment and outcome of these with their complications. Method: A total of 170 cases of cystic swellings of scrotum fulfilling the methodology criteria were subjected to the preformatted study. Diagnosis was mostly by clinical examination and supported by ultrasonography. All cases were treated surgically with the appropriate surgical procedure. Results: Maximum patients were in the age group of 31-50 years and presented with scrotal swelling (59%) and more commonly affecting the right side. The commonest cause for cystic swelling of the scrotum was primary vaginal hydrocele (55%). Surgical procedure using Lords Plication was found to be simple, effective and associated with minimum post operative complications; the other conventional techniques like Partial/sub-total excision of sac, everson of sac were associated with more complications like haematoma, scrotal edema and infection. Majority of patients were discharged on 7th Post-operative day. Conclusion: The present study, primary vaginal hydrocele was the commonest cystic swelling of scrotum and treated surgically showed good results. Lord’s procedure was associated with the less post-operative complications, minimal tissue handling and good haemostatic control

Scope for light assisted fishing in Southeastern Arabian Sea

Scope for light assisted fishing in Southeastern Arabian Se

IMPACT OF ACTIVE LEARNING STRATEGIES TO ENHANCE STUDENT PERFORMANCE

This study is an attempt to discuss the impact of active learning strategies to enhance student performance. Education is an integral part of every human being. It moulds him to be a good citizen, who is really an asset of the country. The wealth of a nation depends on the education of its citizensâ€. Teachers have a noble role in imparting knowledge to the innumerable members in a society. Ever wonder why students pay their tuition and fees, purchase expensive textbooks, rearrange their work schedules and personal lives to enroll in classes, attend classes for short or long periods of time and then suddenly drop the class or simply stop attending? This perplexing question probably has festered in the minds of many college professors those of us who are committed to imparting wisdom, knowledge, and understanding to help shape the minds of our students. Certainly a multitude of reasons could account for the sudden disappearance of our students, who seemingly are plucked away one at a time.  The school teachers, to capture the minds, evoke the interest, and enhance the motivation of those students; obviously there are many answers to this timeless question.  One answer, however, lies in the content of this paper employing active learning strategies in the classroom

Development of bivalve farming as a source of income generation for women’s self-help groups in coastal India

The existing technologies of mussel and oyster farming were converted into an income-generating activity for coastal fishers, particularly for women’s self-help groups. As a result of a concerted approach, coupled with novel extension techniques, commercial mussel and oyster farming became established in the States of India, Kerala and susequently in Karnataka. Production in 2009 was over 20 000 tonnes making India one of the top ten bivalve farming countries in Asia. Innovations in these bivalve farming technologies simplified them, which resulted in an increase in profitability and made them attractive to farmers. During this process, the entire gamut of bivalve farming operations such as site identification, seed and spatfall calendars, remote setting, mechanization in seeding and harvesting, quality and depuration protocols, ready-to-eat and ready-to-cook products, organic farming protocols and environmental impact assessments were worked out. The success in commercializing the technologies was mainly a result of a unique synergy that was actively pursued and developed by technology developers, promoters, and credit advancers. This development scenario can serve as a role model for other states and developing nations where a similar hydrological, social, and market environment exists

Variability in open pollinated seedlings of black pepper (Piper nigrum L.)

Highly heterogeneous variances were observed for plant height, leaf number, leaf width, internode len gth and stem girth in open pollinated seedlings of three black pepper (Piper nigrum) cultivars. Collection 1344 had maximum range and coeffici ent of variation for all the characters followed by Panniyur-1 and a Karimunda Selection KS-27. Eighteen di stinct morphological variants were also recorded in the progeny of Coll. 1344. In some of the progenies, the initial variation sustained wi th growth for most of the morphological features. No such morphological variants were observed in the progenies ofPanniyur-1 and KS-27. The reason for this behaviour of the cultivar is di scussed. &nbsp

Variability in open pollinated seedlings of black pepper (Piper nigrum L.)

Highly heterogeneous variances were observed for plant height, leaf number, leaf width, internode len gth and stem girth in open pollinated seedlings of three black pepper (Piper nigrum) cultivars. Collection 1344 had maximum range and coeffici ent of variation for all the characters followed by Panniyur-1 and a Karimunda Selection KS-27. Eighteen di stinct morphological variants were also recorded in the progeny of Coll. 1344. In some of the progenies, the initial variation sustained wi th growth for most of the morphological features. No such morphological variants were observed in the progenies ofPanniyur-1 and KS-27. The reason for this behaviour of the cultivar is di scussed. &nbsp