Seasonal variations in Secondary Production of the Mandovi-Zuari Estuarine System of Goa

7-9Mean rates of secondary production in the Mandovi, Zuari and Cumbarjua canal, Goa, India were 16.9, 35.9 and 32.4 mg C/m2/day respectively. The general hydrographic conditions of the Zuari were responsible for the higher secondary production. In general, the saline period was more productive (12.9 mg dry wt/m3/day) compared to the low saline period (11 mg dry wt/m3/day). The average secondary production in the estuarine system was 21.4 mg dry wt/m3/day or 1078 tonnes carbon/yr. The coefficient of energy transfer from primary to secondary level was 6.6%. Theoretical estimate of fish biomass in this estuarine system was 1007 tonnes/yr

Molecular analysis of isoniazid-resistant clinical isolates of Mycobacterium tuberculosis from India

The presence of mutations in specific regions of katG, inhA, oxyR–ahpC and kasA associated with isoniazid (INH)-resistant clinical isolates of Mycobacterium tuberculosis from India were analysed by DNA sequencing. Point mutations in the katG gene at codon 315 and a mutation at codon 138 were detected in 64.3% (45/70) and 4% (1/25) of isolates, respectively. Polymorphisms at codon 463 of the katG gene were found both in resistant and sensitive isolates. Mutation at the inhA and oxyR–ahpC promoter regions occurred in 11.4% (8/70) and 35.0% (14/40) of the isolates, respectively. No mutation was found to occur in kasA and inhA structural gene regions. Of the 70 resistant isolates studied, 55 (78.6%) showed mutation in the regions sequenced. This is the first comprehensive molecular analysis of INH resistance in India, which suggests that point mutation rather than deletion and insertion is the major cause of INH resistance

Welding

Friction welding method is one of the most simple, economical and highly productive methods in joining similar and dissimilar metals. It is widely used in the automotive, aircraft and aerospace industrial applications. For many applications it is often necessary to join aluminium (6061) to make finished part. In this project the main aim is to weld the small thickness of aluminum (6061) plates for that friction welding machine used is of higher cost. Here the aim is reduce the cost of friction welding machine with simple parts like three phase A.C induction motor, bush, frame stand, friction tool, universal vice, vertical moving bed, horizontal moving bed, etc. The result expected would be of same strength as that of old friction welding machine. It is very easy and at same time production time is very much reduced. This machine is best suitable for mass production

A Sub-Region Based Space Vector Modulation Scheme for Dual 2-Level Inverter System

This paper deals the implementation of 3-level output voltage using dual 2-level inverter with control of sub-region based Space Vector Modulation (SR-SVM). Switching loss and voltage stress are the most important issues in multilevel inverters, for keep away from these problems dual inverter system executed. Using this proposed system, the conventional 3-level inverter voltage vectors and switching vectors can be located. In neutral point clamped multilevel inverter, it carries more load current fluctuations due to the DC link capacitors and it requires large capacitors. Based on the sub-region SVM used to control IGBT switches placed in the dual inverter system. The proposed system improves the output voltage with reduced harmonic content with improved dc voltage utilisation. The simulation and hardware results are verified using matlab/simulink and dsPIC microcontroller

Reprinted Article “Factors Associated with Early Failure of Arteriovenous Fistulae for Haemodialysis Access”

AbstractThe radiocephalic arteriovenous fistula remains the method of choice for haemodialysis access. In order to assess their suitability for fistula formation, the radial arteries and cephalic veins were examined preoperatively by ultrasound colour flow scanner in conjunction with a pulse-generated run-off system. Intraoperative blood flow was measured after construction of the fistulae. Post-operative follow-up was performed at various intervals to monitor the development of the fistulae. Radial artery and cephalic vein diameter less than 1.6 mm was associated with early fistula failure. The intraoperative fistula blood flow did not correlate with the outcome of the operation probably due to vessel spasm from manipulation. However, blood flow velocities measured non-invasively 1 day after the operation were significantly lower in fistulae that failed early compared with those that were adequate for haemodialysis. Most of the increase in fistula diameter and blood flow occur within the first 2 weeks of surgery

The edge chromatic number of ΓI(R)

For a commutative ring R and an ideal I of R, the ideal-based zero-divisor graph is the undirected graph ΓI(R) with vertices {x∈R−I:xy∈I for some y∈R−I}, where distinct vertices x and y are adjacent if and only if xy∈I. In this paper, we discuss the nature of the edges of ΓI(R). We also find the edge chromatic number for the graph ΓI(R)

Association of conversion & cure with initial smear grading among new smear positive pulmonary tuberculosis patients treated with Category I regimen

Background & objective: Early diagnosis of tuberculosis (TB) is important for initiating treatment to gain cure. The present investigation was undertaken to study the association of conversion and cure with initial smear grading among pulmonary tuberculosis (TB) patients registered in a directly observed treatment – short course (DOTS) programme in Tiruvallur district, south India. Methods: All new smear positive cases registered from May, 1999 to December, 2002 were analysed for conversion and cure related to initial smear grading. Results: Of the 1463 patients, 1206(82.4%) were converted at the end of the intensive phase and 1109 (75.8%) were declared ‘cured’ after the completion of treatment. The cure rate decreased as the initial smear grading increased and the decrease in trend was statistically significant (P=0.01). Similarly, a significant decrease in conversion rate was also observed with increase in initial smear grading (P<0.001). In multivariate analysis, lower cure rate was significantly associated with patient’s age (AOR=1.5, 95% CI=1.1-2.1), alcoholism (AOR=1.7, 95% CI 1.2- 2.4) and conversion at the end of intensive phase (AOR=3.5, 95% CI= 2.6-4.8). Interpretation & conclusion: Cure and conversion rates were linearly associated with initial smear grading. High default and death rates were responsible for low cure and conversion. The proportion of patients who required extension of treatment and those who had an unfavourable treatment outcome were significantly higher among patients with a 3+ initial smear grading. This reiterates the need to pay more attention in motivating these patients to return to regular treatment and sustained commitment in the control of tuberculosis. There is a need to extend the treatment for one more month in the intensive phase of treatment

Influence of drug susceptibility on treatment outcome and susceptibility profile of 'failures' to category II regimen

Objective: To assess the influence of drug resistance on treatment outcome among patients treated with Category-II regimen and document drug susceptibility pattern of “Failures” to this regimen. Design: A retrospective analysis of patients registered from May 1999 through December 2004. Results: Treatment success was 42% among 572 patients and was similar among patients with fully susceptible or resistant but non-MDR organisms (41% of 254 and 40% of 128 patients, respectively). Among 49 MDR-TB patients, 27% had successful treatment outcome. The failure rates among patients with fully susceptible, resistant but non-MDR and MDR bacilli, were 6%, 12% and 27% respectively. Default was significantly higher among males (53% vs. 34%: p<0.01) smokers (57% vs. 36%: p <0.001), alcoholics (58% vs. 39%: p <0.001) and patients with higher initial smear grading (2+ or 3+, 56% vs. scanty or 1+, 44%: p <0.01). DST results were available for 60% (31 of 52) of failures and 10 had MDR-TB. Conclusion: The low success rate to the re-treatment regimen was mainly due to non-compliance. Failure was observed among 9% of patients and MDR-TB was 32% among Category II failures. The currently recommended Category II regimen appears to be adequate for majority of re-treatment cases

Writing Skill of Engineering students of Government and Self-financing Colleges: A Comparative Study

This study compares and analyses the writing performance of engineering students studying in government and Self-financing colleges in Tuticorin district. The subjects of the study comprised of 75 randomly selected first year students from three engineering colleges located in Tuticorin district. The elicitation instrument used for the present study was essay writing and the subjects were asked to write an essay on “Advantages and Disadvantages of using mobile phone.” Descriptive method was adopted for collecting data. The errors were identified and classified into ten categorizations like verb tense, subject-verb agreement, prepositions, conditional sentences, singular/plural form, sentence fragment, word order, spelling, capitalization and double negatives. The results showed that the engineering students made seven most common errors in verb tense, subject-verb agreement, prepositions, conditional sentences, singular/plural form, sentence fragment and word order due to lack of understanding, poor acquisition of grammar rules, intra-lingual errors and interference of the learners’ mother tongue