440 research outputs found
Myostatin dysfunction is associated with reduction in overload induced hypertrophy of soleus muscle in mice
Acknowledgements This project was also supported by Marie Curie International Reintegration Grant 249156 (A. Lionikas) and the grants VP1-3.1-SMM-01-V-02-003 (A. Kilikevicius) and MIP-067/2012 (T. Venckunas) from the Research Council of Lithuania as well as the grant from the Ministry of Higher Education of Saudi Arabia (Y. Alhind). We wish also to thank Mrs Indre Libnickiene for her excellent technical assistance provided during the project.Peer reviewedPostprin
Analytical Predictions for a Natural Spacing within Dyke Swarms
International audienceDykes often grow next to other dykes, evidenced by the widespread occurrence of dyke swarms that comprise many closely-spaced dykes. In giant dyke swarms, dykes are observed to maintain a finite spacing from their neighbors that is tens to hundreds of times smaller than their length. To date, mechanical models have not been able to clarify whether there exists an optimum, or natural spacing between the dykes. And yet, the existence of a natural spacing is at the heart of why dykes grow in swarms in the first place. Here we present and examine a mechanical model for the horizontal propagation of multiple, closely-spaced blade-like dykes in order to find energetically optimal dyke spacings associated with both constant pressure and constant influx magma sources. We show that the constant pressure source leads to an optimal spacing that is equal to the height of the blade-like dykes. We also show that the constant influx source leads to two candidates for an optimal spacing, one which is expected to be around 0.3 times the dyke height and the other which is expected to be around 2.5 times the dyke height. Comparison with measurements from dyke swarms in Iceland and Canada lend initial support to our predictions, and we conclude that dyke swarms are indeed expected to have a natural spacing between first generation dykes and that this spacing scales with, and is on the order of, the height of the blade-like dykes that comprise the swarm
Nosocomial Wound Infection amongst Post Operative Patients and their Antibiograms at Tertiary Care Hospital in India
Nosocomial infection constitutes a major public health problem worldwide. Increasing antibiotic resistance of pathogens associated with nosocomial infections also becomes a major therapeutic challenge for physicians. Thus, the aim of this study was to identify post operative bacterial infections in the patients developing surgical site infections at a tertiary University hospital in North India during July 2013 to Dec 2013.Methods: One hundred and ninety six swabs/pus specimens from various types of surgical sites suspected to be infected onclinical grounds were processed, by standard methods and antibiotic susceptibility testing of all the isolates was done by usingKirby Baur disc diffusion technique.Results: Of the one hundred and fifty-eight organisms isolated, the most common was Staphylococcus aureus (27.8 %), followedby Escherchia coli (24.05 %), Klebsiella pneumoniae (13.29 %), Pseudomonas aeruginosa (6.32%), Klebsiella oxytoca (5%),Enterococcus (5.6%) and other miscellaneous gram negative rods (9.4%) and Streptococcus pyogenes (1.30%). About 50% of theStaphylococcus aureus isolates were found to be methicillin resistant. In case of Escherichia coli, more than one-third of the isolates were found to be ESBL producers. The resistance to third generation cephalosporins and the quinolone ciprofloxacin was also quite high. Other isolates also showed a very high level of antibiotic resistance.Conclusion: In addition to the economic burden for antibiotic treatment, such infections for multi-resistant organisms are a serious threat to our surgical patients. To prevent these happenings, there is ar urgent need to adopt basic principles of asepsis and sterilization and to make judicious use of prophylactic and therapeutic antibiotics and determine current antimicrobial resistance to commonly prescribed drugs.Keywords: Wound infection; microorganisms; anti-microbial sensitivit
Experiments versus theory for the initiation and propagation of radial hydraulic fractures in low permeability materials
We compare numerical predictions of the initiation and propagation of radial fluid-driven fractures with laboratory experiments performed in different low permeability materials (PMMA, cement). In particular, we choose experiments where the time evolution of several quantities (fracture width, radius, wellbore pressure) were accurately measured and for which the material and injection parameters were known precisely. Via a dimensional analysis, we discuss in detail the different physical phenomena governing the initiation and early stage of growth of radial hydraulic fractures from a notched wellbore. The scaling analysis notably clarifies the occurence of different regimes of propagation depending on the injection rate, system compliance, material parameters, wellbore and initial notch sizes. In particular, the comparisons presented here provide a clear evidence of the difference between the wellbore pressure at which a fracture initiates and the maximum pressure recorded during a test (also known as the breakdown pressure). The scaling analysis identifies the dimensionless numbers governing the strong fluid-solid effects at the early stage of growth, which are responsible for the continuous increase of the wellbore pressure after the initiation of the fracture. Our analysis provides a simple way to quantify these early time effects for any given laboratory or field configuration. The good agreement between theoretical predictions and experiments also validates the current state of the art hydraulic fracture mechanics models, at least for the simple fracture geometry investigated here
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Shale Oil Value Enhancement Research. Quarterly Report, June 1 - August 31, 1993
All tasks are on schedule, or ahead of schedule. Particular progress has been made in identifying industrial entities, commodities and specialty products of target interest for shale oil-derived products. There is clearly a major emphasis worldwide on new chemicals and shale oil-derived structures are similar to many of these chemicals of interest. Details of the mathematical modeling, programming and algorithm development have progressed with excellent results. Considerable effort will be required to interface these with the output of the gc/ms but we are receiving excellent support from Hewlett Packard in this regard. The ability to concentrate particularly valuable compounds with reasonable projected cost processes continues to show promise. In one system, a single-stage extraction recovered 87% of the total nitrogen in an extract representing only 33% of the fraction. Special attention is being paid to both nitrogen types and oxygen types. The raffinates from the polar solvent extractions will be evaluated for their oil and wax contents. All of the start-up infrastructure is now in place. Subcontracts have been initiated and equipment and supplies have been procured. We are now planning a major push to reach some general findings by early in 1994. From these findings, we will be prepared to focus on experimental verification of process design needed for the second program phase
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Process/economic strategy for upgrading shale oil
A prime difficulty with the production of transportation fuels from Western US shale oil is the high heteroatom content, especially nitrogen. Nitrogen containing molecules are known to have high market value for non-fuel uses. Selective extraction of nitrogen-containing molecules from shale oil recovers these potentially valuable components while upgrading the remaining shale oil for refining to transportation fuels. A thermodynamically logical separation process sequence consisting of primarily distillation and liquid-liquid extraction has been shown effective in selective isolation of polar heteroatom-containing molecules. The polar fraction may be processed for the production of chemical intermediates and specialty chemicals of high value. Projected material balances show an overall product split of 80% refinery feed and 20% polar products. Based on product values and composition, a preliminary economic analysis yields 30% internal rate of return. A summary of the economic strategy, process results and promising products will be presented
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