54 research outputs found

    Is the outcrop topology of dolerite dikes of the Precambrian Singhbhum Craton fractal?

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    In the Precambrian Singhbhum Craton of eastern India, newer dolerite dikes occur profusely with varying outcrop lengths. We have analysed the nature of their length-size and orientation distributions in relation to the theory of fractals. Two orientational sets of dikes (NW-SE and NE-SW) are present. Both the sets show strongly non-power-law size distributions, as reflected in non-linear variations in logarithmic space. We analyzed thousands of data, revealing that polynomial functions with a degree of 3 to 4 are the best representatives of the non-linear variations. Orientation analysis shows that the degree of dispersions from the mean trend tends to decrease with increasing dike length. The length-size distributions were studied by simulating fractures in physical models. Experimental fractures also show a non-power-law distribution, which grossly conforms to those of the dolerite dikes. This type of complex size distributions results from the combined effects of nucleation, propagation and coalescence of fractures

    Activity controls fragility: A Random First Order Transition Theory for an active glass

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    How does nonequilibrium activity modify the approach to a glass? This is an important question, since many experiments reveal the near-glassy nature of the cell interior, remodelled by activity. However, different simulations of dense assemblies of active particles, parametrised by a self-propulsion force, f0f_0, and persistence time, τp\tau_p, appear to make contradictory predictions about the influence of activity on characteristic features of glass, such as fragility. This calls for a broad conceptual framework to understand active glasses; here we extend the Random First-Order Transition (RFOT) theory to a dense assembly of self-propelled particles. We compute the active contribution to the configurational entropy using an effective medium approach - that of a single particle in a caging-potential. This simple active extension of RFOT provides excellent quantitative fits to existing simulation results. We find that whereas f0f_0 always inhibits glassiness, the effect of τp\tau_p is more subtle and depends on the microscopic details of activity. In doing so, the theory automatically resolves the apparent contradiction between the simulation models. The theory also makes several testable predictions, which we verify by both existing and new simulation data, and should be viewed as a step towards a more rigorous analytical treatment of active glass

    GUEST EDITORIAL

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    Nanoelectronic devices of various kinds of are essential for VLSI circuits. The struggle to follow Moore’s law is becoming increasingly difficult and complex, requiring multitudinous novel approaches in order to continue decreasing dimensions of the devices which are already firmly established in the nano-world. As an example, the most advanced state of the art VLSI’s (microprocessors) currently can contain more than 50 billion transistors per chip. As far as the actual physical dimensions are concerned, in 2021 the IBM company announced their 2 nm chip.The efforts behind such achievements are enormous. This special issue on advanced planar nanoelectronics investigates some points of interest related to the physics of such devices, as well as their simulation, thus giving its contribution to the existing trends in this rapidly evolving and constantly expanding field

    Effects of clomiphene citrate on seminal parameters in idiopathic oligospermia: a single blinded prospective randomized controlled trial

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    Background: About 15% married couples face problem of infertility of which male factor is implicated in 20% of them. In about 30% infertile men no causative factor is found and the condition is termed “Idiopathic”. They are often treated by empirical medications or Assisted Reproductive Technologies (ART) although success in few; our present study is carried on effects of clomephene citrate on seminal parameters in idiopathic oligospermia.Methods: This single blinded prospective randomized controlled trial was conducted at the infertility clinic with 200 idiopathic oligospermic men (sperm count 2 years is more in group C than group p (4.3±3.06 versus 4.1±2.57). The semen volume, spermatozoa count, sperm motility and not normal form are all increased after three months of treatment in group C as are biochemical parameters like total testosterone and serum FSH, LH and as also pregnancy rate (22% versus 4%).Conclusions: This study showed clomiphene citrate treatment protocol is inexpensive, relatively safe and easy to administer and improves semen volume, sperm count and sperm motility but not sperm morphology by increasing serum testosterone, FSH and LH in male and resulting in improved pregnancy rate in female partners

    Exploitation of IAA Producing PGPR on mustard (Brassica nigra L.) seedling growth under cadmium stress condition in comparison with exogenous IAA application

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    Soil pollution by cadmium (Cd) is a global threat for plants and animals. Exogenous auxin application reduces the Cd stress on plants. Moreover, IAA production by rhizospheric bacteria can play a key role in plant growth and development by promoting cell division, cell elongation, cell differentiation, flowering and lateral root formation. The present study was to evaluate the efficiency of IAA producing, Cd tolerant plant growth promoting rhizobacteria for plant (Brassica nigra L.) growth under Cd stressed condition comparing with the external synthetic auxin application. Lysinibacillus varians and Pseudomonas putida were isolated previously as IAA producing PGPR and selected in this study for their exploitation in plant growth development under Cd stressed condition. The impact of external synthetic IAA application significantly increased the plant growth under Cd amended soil. Whereas, PGPR inoculation also showed significant (p<0.05) elevation in germination percentage, root and shoot length, chlorophyll content and other growth parameters of Cd stressed Brassica plants which were comparative to synthetic IAA application. So, these selected PGPRs (L. varians and P. putida) can be used as biofertilizer which ameliorate the adverse effect of cadmium

    Pre-clinical risk assessment and therapeutic potential of antitumor lipopeptide ‘Iturin A’ in an in vivo and in vitro model

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    Lipopeptides are versatile bio-active weapons having antifungal, antibacterial, antimycoplasma and anticancer properties. In this study, the therapeutic potential and safety assessment of a lipopeptide molecule ‘Iturin A’ were evaluated. Iturin A was found to inhibit in vivo tumor growth in a sarcoma 180 mouse xenograft model. The antitumor efficacy of Iturin A was correlated with increased DNA fragmentation and modulation of CD-31, Ki-67, P-Akt, P-MAPK, apoptotic and anti-apoptotic proteins. Further, safety assessment was carried out in Sprague Dawley rats by 28 days repeated dose (28 days) toxicity and a bio-distribution study. In the toxicity study, Iturin A (10, 20 and 50 mg per kg per day) was administered to the animals for 28 days. Another group was kept for another 14 days without drug exposure after 28 days of treatment to access the reversibility of the toxicity. At the end of the treatment, body weight, food and water intake, organ weight, motility, hematology, serum biochemistry and histopathology of the major organs were evaluated. The bio-distribution of Iturin A was also performed in plasma as well as in different major organs by a well-developed and validated administration of Iturin A radiolabeled with 99mTc. The in vitro cytotoxic effect of Iturin A was also evaluated in BRL-3A rat liver cells. In the treated groups, various toxicities were found in the liver and spleen. However, these adverse effects were transient and reversible after discontinuation of Iturin A treatment. In conclusion, this pre-clinical study offered a preliminary investigation regarding the efficacy and safety assessment of Iturin A
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