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Survival of industries has become more critical in the present global competitive business environment unless they produce their projected production levels. The accomplishment of this can be possible only by maintaining the men and machinery in an efficient and effective manner. Hence, it is more essential to estimate the performance of utilized equipment for reaching/achieving future goals. The present study focuses on the estimation of underground mining machinery such as the load–haul–dump machine performance characteristics using ‘Isograph Reliability Workbench 13.0’ software. The allocation of best-fit/goodness-of-fit distribution was made by utilizing the Kolmogorov–Smirnov test (K–S) test. The parameters were recorded based on the best-fitted results using the maximum likelihood estimate test. Further, a feed-forward-back-propagation artificial neural network (ANN) tool has been used to develop the models of reliability, availability and preventive maintenance time intervals. The number of neurons was selected with the Levenberg–Marquardt learning algorithm in the hidden layer as the optimal value. The output responses were predicted corresponding to the optimal values. Further, an attempt has been made to validate the computed results with ANN predicted responses. The recommendations are suggested to the industry based on the results for the improvement of system performance.

The present research focuses on the timing of wing–wing interaction that benefits the aerodynamic force of a dragonfly in hovering flight at Reynolds number 1350. A 3-D numerical simulation method, called the system coupling, was utilised by implementing a two-way coupling between the transient structural and flow analysis. We further explore the aerodynamic forces produced at different phase angles on the forewing and hindwing during the hovering flight condition of a dragonfly. A pair of dragonfly wings is simulated to obtain the force generated during flapping at a 60° inclination stroke plane angle with respect to the horizontal. The hovering flight is simulated by varying the phase angle and the inter-distance between the two wings. We observe a significant enhancement in the lift (16%) of the hindwing when it flaps in-phase with the forewing and closer to the forewing, maintaining an inter-wing distance of 1.2 cm (where cm is the mean chord length). However, for the same condition, the lift of the hindwing reduces by 9% when the wings are out of phase/counterstroke flapping. These benefits and drawbacks are dependent on the timing of the interactions between the forewing and hindwing. The time of interaction of wake capture, wing–wing interaction, dipole structure and development of root vortex are examined by 2-D vorticity of the flow field and isosurface of the 3-D model dragonfly. From the isosurface, we found that the root vortex elicited at the root of the hindwing in counter-flapping creates an obstacle for the shedding of wake vortices, which results in reduction of vertical lift during the upstroke of flapping. Hence, at the supination stage, a dragonfly uses a high rotation angle for the hovering flight mode. It is observed that the system coupling method was found to be more efficient and exhibited better performance. The present numerical methodology shows a very close match to the previously reported results.

The effect of trifluoperazine (TFP), a calmodulin antagonist, was investigated on in vitro ATP levels of human derived Mycobacterium leprae. M. lepraewere obtained from biopsies from multi‐bacillary forms of leprosy and were incubated in a modified Dubos medium system which supports limited in vitro synthesis of M. leprae. This incubation was carried out in the absence and presence of different concentrations of trifluoperazine. Samples for estimation of bacillary ATP levels were taken at day 0 and at 14 days of incubation. TFP inhibited ATP levels in M. lepraeand this inhibitory effect was marginal at 2.5 μg ml−1(35% inhibition), highly significant at 5 μg ml−1(87% inhibition) and almost total at 10 μg ml−1(98.5% inhibition). This compound appears to have potential as an anti‐leprotic drug and also as a broad spectrum anti‐mycobacterial agent in view of its anti‐tubercular activity reported earlier.

We have recently demonstrated that the calmodulin antagonist trifluoperazine has antitubercular activity in vitro against Mycobacterium tuberculosis H37Rv susceptible and resistant to isoniazid. It is shown that trifluoperazine at a concentration of 50 μ g ml−1 when added to the cells along with the labelled precursors inhibited the incorporation of [14C]acetate into lipids (63%) and uptake of [14C]glycine (74%) and [3H]thymidine (52%) bu whole cells of M. tuberculosis H37Rv by 6 h of exposure. After 48 h, the inhibition was 87%, 97% and 74%, respectively. However, when the drug was added to cells taking up and metabolizing the labelled precursors at a later point (3 h for [14C]acetate and [3H]thymidine and 12 h for [14C]glycine) it inhibited completely the uptake of all the precursors, at least up to 24 h. The onset of inhibitory action was very rapid, i.e. 3 h. It is suggested that trifluoperazine has multiple sites of action and acts probably by affecting the synthesis of lipids, proteins and DNA.

When Mycobacterium smegmatis TMC1546 was grown at different concentrations of glucose supplemented to a synthetic medium already containing 2% v/v glycerol, the following changes were observed. Amount of calmodulin-like protein (CAMLP), total and individual phospholipids (PLs) namely phosphatidylethanolamine, cardiolipin, phosphatidylglycerol and phosphatidylinositol mannosides and total lipids and growth increased up to 5% w/v but decreased at higher concentrations of glucose (7.5% w/v and above). Cyclic AMP content of the whole cells decreased continuously with increase in glucose concentration in the medium. Incorporation of 32Pi into total phospholipids was inhibited by two calmodulin antagonists trifluoperazine and phenothiazine (50% at 40 μM) and the calcium-specific chelator ethylene glycol bis (β-aminoethyl ether) N,N,N′,N′-tetraacetate (EGTA) 35% at 2 mM. Total lipids, CAMLP and growth of this organism are also modulated in a similar way in response to the glucose concentration in the growth medium. Taking these observations together it is suggested that CAMLP has some effect on the metabolism of PLs.