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Background: Early diagnosis and treatment of drug-resistant tuberculosis (TB) is crucial to halt the spread of drug resistance in the community. Aim: The aim of the study was to compare rapid diagnostic tests (GeneXpert and line probe assay, LPA) with conventional liquid culture for the diagnosis of drug-resistant TB and to assess the risk factors for it. Method: This cross-sectional study recruited 229 multidrug-resistant TB suspects who were sputum smear positive. They were evaluated by the rapid diagnostic tests and sensitivity, specificity, positive predictive value and negative predictive value were calculated for drug resistance detection as compared to liquid culture drug susceptibility testing. The risk factors for the development of drug resistance were also assessed and the P value of < 0.05 was considered significant. Results: In the final comparison, 193 samples were included. The sensitivity and specificity of GeneXpert for detection of drug resistance (rifampicin) was 100% (95% confidence interval, CI: 88.8–100%) and 99.4% (95% CI: 96.6–99.9%), respectively. Whereas sensitivity and specificity of LPA was 94.3% (95% CI: 80.8–99.3%) and 100% (95% CI: 97.7–100%), respectively. Only three discordant samples were observed. Defaulting to antitubercular therapy, contact with resistant TB, and disseminated disease were found to be significant risk factors for the development of drug-resistant TB with high statistical significance (P value < 0.05). Conclusion: Both rapid diagnostic tests have very high sensitivity and specificity for detection of drug resistance in sputum smear positive with the advantage of short turn-around time. Defaulting to antitubercular therapy, contact with resistant TB, and disseminated disease are significant risk factors for drug resistance.

Objective: The study was conducted to determine whether synthetic Disease-Modifying Anti Rheumatic Drugs (DMARDs) suppress the latency of Tuberculosis (TB) infection in Rheumatoid Arthritis (RA) patients along with other variables. Methods: This was done through Tuberculin Skin Test (TST) using purified protein derivative (PPD) in a cohort of RA patients. The TST was taken positive when induration post-PPD injection was ≥ 5mm and negative or anergic when it was Results: The prevalence of positive TST was 36%, while 64% presented a negative result. Negative TST was significantly associated with steroid usage (39.4%, 95% CI: 28.4%-51.4%). Anergic (TST negative) and non-anergic (TST positive) patients were separated into groups, and a new analysis was conducted with elaboration on DMARDs used. Conclusion: The use of steroids was associated with TST negativity, The same is not true with use of methotrexate or other DMARDs. Thus TST should be interpreted with caution, especially before starting biologicals.

A wind tunnel study was carried out to investigate the fluidelastic stability of a model heat exchanger tube array subjected to a uniform cross-flow of air and a concentrated jet flow of air down a tube lane. The latter experiments were intended to simulate the effects of a soot blower on the dynamic response of the tubes which had apparently been the cause of catastrophic tube failure in a heat exchanger. The experimental results showed that the model tube array experienced fluidelastic instability when subjected to a uniform cross-flow beyond a dimensionless pitch flow velocity of 24.4. For a mass damping parameter of 14.5, the Connors’ constant for this array is K = 6.4 which is over 2-1/2 times that of the conservative guideline of K = 2.4 recommended by the ASME boiler and pressure vessel code. These experiments established that the normal operating conditions of the heat exchanger should not lead to excessive tube vibration. It was shown that a continuously translating nozzle dispensing a jet of air at the tubes caused some static deflection of the tubes but no serious vibrations were observed that would be of concern from the standpoint of tube damage. However, when the nozzle was fixed at one location whereby the jet of air issued directly down a tube lane, fluidelastic instability occurred in the tubes in the first few rows, but some time was required for large amplitude vibrations to develop. It can be inferred that, for heat exchangers equipped with steam soot blowers, normal soot blower operation should not cause fluidelastic instability but that a parked soot blower can be expected to cause fatigue failure of the tube adjacent to the impinging jet in a relatively short period of time.Copyright © 2003 by ASME

The effects of salinity at 50 mm NaCl on floral characteristics, yield components, and biochemical and physiological attributes of the sensitive rice variety IR-28 were studied under controlled conditions to determine the causes of sterility in seed set under salinity stress. The results showed significant decreases in panicle weight, panicle length, primary branches/panicle, filled seeds/panicle, unfilled seeds/panicle, filled seeds/plant, unfilled seeds/plant, total seeds/panicle, total seed weight/panicle, 1000-seed weight and total seed weight/plant. The sodium content in different leaves and floral parts increased significantly. In contrast, the potassium content was decreased significantly in leaves and floral parts. A reduction in chlorophyll a and b was also noted in different parts of the leaves. Inhibition of transpiration and photosynthesis was observed in flag leaves at the grain-filling stage. Soluble carbohydrates in different leaves were reduced significantly in salinized plants but their content in different floral parts was increased, with the exception of primary and secondary branch spikelets. Under salinity stress, total protein concentration in flag, second and third leaves were higher than in control plants. The viability of rice pollen was reduced significantly in salinized plants. It was further observed that starch synthetase activity (alpha1-4-glucan glucosyle transferases) in developing rice grains was inhibited very significantly under salinity stress. From these results, it is inferred that sterility and significant reductions in seed set in rice were not merely due to reduction or inhibition of different biochemical constituents and physiological functions, but were mainly due to limitation of soluble carbohydrate translocation in primary and secondary spikelets, accumulation of more sodium and less potassium in all the floral parts, and highly significant inhibition of specific activity of starch synthetase in developing rice grains, thus resulting in failure of seed set.

A wind tunnel study was carried out to investigate the fluidelastic stability of a model heat exchanger tube array subjected to a uniform cross-flow of air and a concentrated jet flow of air down a tube lane. The latter experiments were intended to simulate the effects of a soot blower on the dynamic response of the tubes which had apparently been the cause of catastrophic tube failure in a heat exchanger. The experimental results showed that the model tube array experienced fluidelastic instability when subjected to a uniform cross-flow beyond a dimensionless pitch flow velocity of 24.4. For a mass damping parameter of 14.5, the Connors’ constant for this array is K = 6.4 which is over 2-1/2 times that of the conservative guideline of K = 2.4 recommended by the ASME boiler and pressure vessel code. These experiments established that the normal operating conditions of the heat exchanger should not lead to excessive tube vibration. It was shown that a continuously translating nozzle dispensing a jet of air at the tubes caused some static deflection of the tubes but no serious vibrations were observed that would be of concern from the standpoint of tube damage. However, when the nozzle was fixed at one location whereby the jet of air issued directly down a tube lane, fluidelastic instability occurred in the tubes in the first few rows, but some time was required for large amplitude vibrations to develop. It can be inferred that, for heat exchangers equipped with steam soot blowers, normal soot blower operation should not cause fluidelastic instability but that a parked soot blower can be expected to cause fatigue failure of the tube adjacent to the impinging jet in a relatively short period of time.