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1.
Nature watch     
Deer are some of the commonest, most visible, and attractive mammals in many forests and grasslands of India. They display a fascinating variety in their antlers, social systems, herd-forming behaviour, and ecology. Unfortunately, several factors have brought some species to the brink of extinction today.  相似文献   
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Priti Shankar 《Resonance》1996,1(10):26-36
Linear algebraic codes are an elegant illustration of the power of Algebra. We introduce linear codes, and try to explain how the structure present in these codes permits easy implementation of encoding and decoding schemes.  相似文献   
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An accurate measurement of force and biomechanical energy that people can impart through kicking is useful for kick-related sports training. Existing methods are indirect measurements or focus on force and not on the total energy of the kick. A kick test rig was designed, constructed and instrumented to measure the force and displacement of a vertical target subjected to kicking. The kick energy was calculated from the recorded force and displacement histories. The methodology for measurement of kick force and energy was validated by an open stance front kick test by 52 volunteers. The results showed that 67% of the participants could achieve an average energy above 100 J. An increasing trend of kick energy with increasing body weight of participant was observed. The participant’s gender had a strong influence on the kick energy, while training in martial arts does not appear to be a significant parameter. A probability analysis showed that one in one hundred adults will be able to kick with energies exceeding 215 J.  相似文献   
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Authors report here a survey of medical student feedback on the effectiveness of two different anatomy curricula at Christian Medical College, Vellore, India. Undergraduate medical students seeking the Bachelor in Medicine and Bachelor in Surgery (M.B.B.S.) degrees were divided into two groups by the duration of their respective anatomy curriculum. Group 1 students had completed a longer, 18‐month curriculum whereas Group 2 counterparts followed a shorter, 12‐month curriculum. Students' responses to a questionnaire were studied. Analysis of feedback from Groups 1 and 2 contrasted the effectiveness of the two anatomy curricula. The coverage of gross anatomy was rated adequate or more than adequate by 98% of Group 1 and 91% of Group 2. A desire for greater emphasis on gross anatomy teaching was expressed by 24% of Group 1 and 50% of Group 2 (P = 0.000). Two‐thirds of all students felt that the one‐year program was not adequate, and 90% of Group 1 and 74% of Group 2 felt that clinically oriented anatomy teaching required more emphasis. Dissection was helpful or very helpful for 94% of Group 1 and 88% of Group 2. This study suggests that a better understanding of gross anatomy was gained from a course of longer duration (18 months with 915 contact hr vs. 12 months with 671 contact hr). Students who completed the longer anatomy course had greater appreciation of the need for clinically oriented anatomy teaching and dissection. Anat Sci Educ 2:179–183, 2009. © 2009 American Association of Anatomists.  相似文献   
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Nature watch     
In our previous article ‘On observing the night sky’1 we had introduced the reader to the stars and constellations and suggested how they may be observed. In this article we will provide a few technical details, which we had deliberately left out earlier and also introduce the reader to a number of the other remarkable objects that may be seen in the sky.  相似文献   
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Plant Growth Promoting Rhizobacteria   总被引:1,自引:0,他引:1  
Plant Growth Promoting Rhizobacteria (PGPR) are a group of bacteria that enhances plant growth and yield via various plant growth promoting substances as well as biofertilizers. Given the negative environmental impact of artificial fertilizers and their increasing costs, the use of beneficial soil microorganisms such as PGPR for sustainable and safe agriculture has increased globally during the last couple of decades. PGPR as biofertilizers are well recognized as efficient soil microbes for sustainable agriculture and hold great promise in the improvement of agriculture yields.  相似文献   
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In 1904, Prandtl proposed the concept of boundary layers that revolutionised the study of fluid mechanics. In this article we present the basic ideas of boundary layers and boundary-layer separation, a phenomenon that distinguishes streamlined from bluff bodies.  相似文献   
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Archimedes     
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Malondialdehyde (MDA) is widely used as oxidative stress biomarker in biomedical research. Plasma is stored in deep freezers generally till analysis. Effect of such storage on MDA values, which may be variable and prolong, was incidentally observed in the ongoing study which is to estimate oxidative stress with oral iron. Plasma from blood samples of pregnant women (20–30 years age) in third trimester of singleton pregnancy (n = 139), consuming oral iron tablets was stored at −20 °C with intention of MDA estimation, as soon as possible. However logistic problems led this storage for prolonged and variable period (1–708 days). When values of MDA estimated using “Ohkawa” 79 method and readings were plotted against time to check the temporal effect, it showed a hyperbolic curve. Standard deviation (SD) was lowest when samples were tested within 3 weeks time. The samples analyzed within 3 weeks had mean ± SD value of 31.59 ± 26.11 μmol/L, while 123.7 ± 93.97 and 366.5 ± 189.8 μmol/L for samples stored for 1–3 and 4 months to 1 year respectively. Mean ± SD were 539.9 ± 196.8 in the samples store for more than a year. Rate of change in values was also lowest (0.0433 μmol/L/day) in the samples tested within first 3 weeks, which rose to 1.2 μmol/L/day during 3 month’s storage. This rate peaked at storage of 120 days (1.87 μmol/L/day) and fell to 0.502 μmol/L/day in the second year of storage. It is concluded that at −20 °C, only 3 weeks of storage time should be considered valid for fairly acceptable stability in MDA values.  相似文献   
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