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91.
Arsenic contamination of ground water has become a serious problem all over the world. Large number of people from Uttar Pradesh, Bihar and West Bengal of India are suffering due to consumption of arsenic contaminated drinking water. Study was carried out on 30 individuals residing in Ballia District, UP where the maximum concentration of arsenic was observed around 0.37 ppm in drinking water. Blood samples were collected from them to find out the problem related with arsenic. Cytogenetic study of the blood samples indicates that out of 30, two persons developed Klinefelter syndrome.  相似文献   
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Addressing the need for suicide prevention on campus, I CARE training, developed and facilitated by counseling center clinicians, trains students, staff, and faculty to provide support to students experiencing distress or mental health problems. We assessed its impact using a mixed-methods approach. Quantitative analyses demonstrated significant increases in knowledge of intervention skills and readiness to intervene from pretraining to posttraining. Knowledge and readiness remained significantly higher than preworkshop for the entire follow-up evaluation period, extending 15 months posttraining. Qualitative analyses revealed the value of experiential activities and emotional processing in increasing participants’ comfort and preparedness to intervene in challenging situations.  相似文献   
94.
INTRODUCTION The physics of plastic deformation and crack propagation at atomic level is complex but is essential for the development of new materials. This requires an understanding of the atomic level phenomena associated with the plastic deformation. In this con- text, emission of electromagnetic radiation (EMR) during plastic deformation and crack propagation in metals and alloys, and generation of transient mag- netic fields during crack initiation in ferromagnetic materials are rep…  相似文献   
95.
INTRODUCTION The particle swarm optimization (PSO) method is a member of the broad category of swarm intelli- gence techniques for finding optimized solutions. The PSO algorithm is based on the social behavior of animals such as flocking of birds and schooling of fish, etc. PSO has its origin in simulation for visual- izing the synchronized choreography of bird flock by incorporating concepts such as nearest-neighbor ve- locity matching and acceleration by distance (Par- sopoulos and V…  相似文献   
96.
Shivam Kumar 《Resonance》2007,12(10):18-29
In the first part of this article, we had introduced the notion of quadratic reciprocity and dwelt briefly on its history, which goes back all the way to the work of Fermat. Then we discussed the Law of Quadratic Reciprocity (‘QRL’), which Gauss named Theorema Aureum. Following this, we gave a not too well known proof of the QRL, due to G Rousseau. Now we give two more proofs of the QRL, drawing respectively from ideas in linear algebra and field extensions; they too are not very well known. Shivam Kumar graduated from Indian Statistical Institute, Bangalore and is joining the London School of Economics for MSc in applicable mathematics. His interest lies in expanding the existing applied paradigm of mathematics from stock market to unchartered subjects such as sociometrics.  相似文献   
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Traditionally the kinetics of a chemical reaction has been studied as a set of coupled ordinary differential equations. The law of mass action, a tried and tested principle for reactions involving macroscopic quantities of reactants, gives rise to deterministic equations in which the variables are species concentrations. In recent years, though, as smaller and smaller systems – such as an individual biological cell, say – can be studied quantitatively, the importance of molecular discreteness in chemical reactions has increasingly been realized. This is particularly true when the system is far from the ‘thermodynamic limit’ when the numbers of all reacting molecular species involved are several orders of magnitude smaller than Avogadro’s number. In such situations, each reaction has to be treated as a probabilistic ‘event’ that occurs by chance when the appropriate reactants collide. Explicitly accounting for such processes has led to the development of sophisticated statistical methods for simulation of chemical reactions, particularly those occurring at the cellular and sub-cellular level. In this article, we describe this approach, the so-called stochastic simulation algorithm, and discuss applications to study the dynamics of model regulatory networks.  相似文献   
99.
Ongoing curriculum change in higher education is essential to enhance student learning and better prepare them for the job‐market. However, research shows that faculty are reluctant to implement such changes because students generally react adversely thereby negating any potential benefits, and moreover, sanction faculty through lower evaluations and future enrollment. Yet, understanding of the effect of curriculum changes on students’ course and instructor perceptions is limited. In this article we attempt to fill this gap. Drawing on two empirical findings—students’ motivation to attend college becoming increasingly extrinsic since the 1960s and their inability to recognize, ex ante, the value‐added by a curriculum change—and the norm life‐cycle theory, we argue that any effort‐increasing or grade‐threatening change is viewed as non‐normative and will lead to an adverse student reaction. However, this adverse reaction will dissipate over time once a critical mass of students is convinced of the merits of the new curriculum. We find support for our hypotheses by analyzing change in student perceptions following curriculum changes at a U.S. University. In addition, we also find that once the adverse reaction dissipates, students’ perceptions of the new curriculum become more positive than the old curriculum, only to be reversed once the revised curriculum is accepted as the new norm.  相似文献   
100.
In Part I, the nature of scalars and vectors was discussed for the Newtonian world. However, in the relativistic world, physical quantities follow Lorentz transformations. This change of transformation from Galilean to Lorentz results in interesting distinctions in their properties: mass and time are no longer scalars, time and space become intertwined, etc. This part discusses the nature of scalars and vectors in the relativistic world.  相似文献   
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