Assessment of renal acidification capacity of stone formers by acid challenge test

Acid challenge test was carried out on 87 subjects (37 normal and 50 radiologically proven stone formers) to assess their renal acidification capacity. NS were given three doses viz. 75, 100 and 150 mg NH₄Cl/Kg body weight while the SF were tested with only 150 mg dose which was found to be an adequate dose. Ammonium chloride was given in gelatin capsules with breakfast and hourly urine samples were collected for next 7 hours. pH, creatinine, calcium, inorganic phosphorus, citrate, titrable acid and ammonium were analysed in all the samples. The incidence of renal tubular acidosis (RTA) in NS, tested with 75 mg and 100 mg/kg doses of ammonium chloride, was 50% and 10% respectively while it was nil and 24% respectively in NS and SF tested with 150mg/kg dose. Complete RTA was detected in one SF. No significant difference was observed in urinary profile of NS and SF except that the hourly titrable acid excretion was lower in later. A comparison between with and without RTA SF revealed that titrable acid and phosphate excretion decreased in RTA defect. Overall data indicate that (a) RTA was an etiologic factor in one fourth of the SF; (b) an oral acid challenge test is a good adjunct to detect this condition and (c) acid challenge increases calcium, phosphate and titrable acid excretion and decreases citrate.     

Circadian variation of human circulating cholesterol components on vegetarian and omnivorous diets in healthy Indians

Circadian periodicity of human circulating total (T), high-density lipoprotein (HDL) and low-density lipoprotein (LDL + VLDL; briefly LDL) cholesterol (C) was studied in 30 clinically healthy, diurnally active, norturnally resting young volunteers divided into two groups of 15 each (10 men; 5 women) taking vegetarian and non-vegetarian diets. A marked circadian variation in T-C, HDL-C and LDL-C was recorded in all volunteers irrespective of the diety habits. However, total mean values and the acrophase differed between the two groups. Lower MESOR of studied variables for the vegetarians and higher MESOR for the omnivores in both the sexes exhibited endogeneous rhythmic changes as well as lower values of cholesterol components in vegetarians as compared to omnivores. Fasting unmasks a presumably endogeneous change around a lower MESOR with a smaller circadian amplitude both of HDL and LDL cholecterol metabolism. The recognition that the human circulating cholesterol components oscillate physiologically, in the peripheral blood with a shift of acrophase according to a circadian rhtyhm in two dietry schedules may prove to be of significance in the clinical interpretation of the laboratory result under tropical conditions.     

Recent insights on biochemical and molecular basis for developing antihaemostatic agents: A review

The normal coagulation process is initiated by disruption and exposure of the subendothelial components of blood vessels. Platelets adhere to subendothelium-bound von Willebrand factor via glycoprotein (GP) Ib complex. This initial interaction per se and the release of platelet agonists transduce signals that leads to the rise in intracellular Ca2+ which induces shape change, prostaglandin synthesis, release of granular contents and conformational changes in platelet Gp IIb-IIIa. Gp IIb-IIIa in activated platelets binds fibrinogen and other adhesive proteins and mediates platelet cohesion the primary haemostatic plug. Furthermore, the activated platelets due to aggregation, result in the formation of fibrin (secondary hemostasis). Normally the haemostatic process plays a delicate balance between keeping the blood in the fluid state to maintain flow and rapidly forming an occluding plug following vessel injury. Thrombosis occurs because of alteration in this delicate balance. Arterial thrombosis occurs in the setting of previous vessel wall injury mostly because of atherosclerosis, while venous thrombosis occurs in areas of stasis. The recent advances in understanding of the haemostatic process have led to a better understanding of the mechanism of action of many antithrombotic drugs and identification of new targets for drug development. The molecular target of the ticlopidine has been identified. Large numbers of IIb-IIIa inhibitors have been developed. The mechanism of action of heparin has been defined at the molecular level. As a result, a synthetic pentasaccharide, based on antithrombin-binding domain of heparin, has been developed and tested successfully in clinical trials. New generation direct thrombin inhibitors are being developed. Factor Xa has a critical position at the convergence of intrinsic and extrinsic pathway. The clinical tolerability and the efficacy of low molecular weight heparins has established that inhibition of further thrombin generation, by blocking factor Xa alone can be an effective way of preventing thrombus growth without inactivating thrombin. A large number of specific factor Xa inhibitors are under development. Some of these are in preliminary clinical trials and appear to be promising. Future clinical trials will determine whether these new drugs will provide better risk-benefit ratio in treatment of thrombotic disorders. Similarly role of thrombolytics has been clearly established in many diseases including coronary artery disease.     

Developing a community of thinking: assessment of environmental education

This paper discusses an oral assessment intervention in environmental education at two tertiary institutions in South Africa. A qualitative study grounded in a social constructivist framework, the inquiry locates learning and assessment of environmental education based on practical activities and first‐hand experience within the framework of situated learning, and explores processes of constructing and assessing knowledge within the learner's community of practice. The paper focuses on how communities of practice can be used as a possible learning approach in environmental education to address the diversity and challenges of classrooms, and on the efficacy of oral assessments structured to encourage thinking through dialog in such settings.     

Joint routing and rate allocation for multiple video streams in ad-hoc wireless networks

INTRODUCTION Ad-hoc networks are attractive owing to their self-organizing nature and absence of a fixed infra- structure. They are particularly suited for communi- cation in disaster-affected areas, coordinating military operations, and sensing environmental conditions With the growing availability of supporting hardware and decreasing equipment cost, ad-hoc networking based applications are proliferating. Meshes of wire- less nodes are being deployed in cities and housing communities to…     

A Practical Introduction to Authoring for Computer-Assisted Instruction. Part 5: PHILVAS

Interactive videodisc technology is likely to have a significant impact upon many aspects of education and training. However, before this medium can be effectively utilized considerable attention must be given to overcoming the present problems associated with courseware authoring. Solutions to these problems are to be found in the provision of suitable courseware development aids. In particular, there is a requirement for a powerful and easy-to-use author language. This paper describes the approach used by the PHILVAS authoring system.     

Pedagogical issues in distance education

Head of the Distance Education Division, Central Institute of Educational Technology, National Council of Educational Research and Training, New Delhi. Previous founder director of the Open School of India. Member of numerous committees and commissions at national level, in particular, the National Task Force on Broadcasting for Education (1980/81) and the Commission for Teachers — I Task Force (1983/84). Author or co-author of five books, including Open School India,and numerous articles.     

Tolerant Inclusion: racialised experiences of Asian Australian pre‐service teachers

In this paper we examine the educational experiences of Asian Australian women enrolled in a Faculty of Education in an urban university. We argue that the everyday social relations of pre‐service teacher education are constituted by discourses of liberal tolerance which call for a celebration of difference and diversity. This celebratory discourse suppresses, and thereby denies, the unequal power relations between the Anglo‐Celtic majority and ethnic, racialised minority groups. Discourses of liberal tolerance position the Anglo‐Celtic majority to be either tolerant or intolerant of its ethnicised and racialised Other(s). However, social interactions cannot be simply analysed in terms of a binary logic of tolerance or intolerance of the Other. Social interactions between members of majority and minority groups are complex; inherently contradictory and ambivalent. In this paper we explore these complex dynamics in the everyday experiences of Asian Australian women enrolled in a teacher‐education course     

Educational practice in India and its foundations in Indian heritage: a synthesis of the East and West?

The paper examines education practice in India in terms of the division between indigenous cultures on the one hand, and the formal culture of learning and knowledge systems inherited from colonial times on the other. These ‘two Indias’ are still reflected in the modern educational system in India, seen in the vast differences between the formal school system, whose benefits reach only a minority of the population, and the millions of crafts-persons working in India's informal sector, many without education or training. The paper looks at reasons for these divisions within the culture and history of India's formal, non-formal and informal systems of education and training. The paper also throws light on the aspirations to unite these divided cultures of learning by looking at some of the writings of J.P. Naik, the famous educationist and secretary of the first Report of the Education Commission (1964–66) after India's independence. The analysis needs to be seen against the background of international educational thought which is improving the value, relevance and quality of non-formal and informal learning, as key pillars for building lifelong learning systems.