Nanoshearing - Collective carbon nanotube micromechanics

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Spatial-temporal evolution of the current filamentation instability

The spatial-temporal evolution of the purely transverse current filamentation instability is analyzed by deriving a single partial differential equation for the instability and obtaining the analytical solutions for the spatially and temporally growing current filament mode. When the beam front always encounters fresh plasma, our analysis shows that the instability grows spatially from the beam front to the back up to a certain critical beam length; then the instability acquires a purely temporal growth. This critical beam length increases linearly with time and in the non-relativistic regime it is proportional to the beam velocity. In the relativistic regime the critical length is inversely proportional to the cube of the beam Lorentz factor $\gamma_{0b}$. Thus, in the ultra-relativistic regime the instability immediately acquires a purely temporal growth all over the beam. The analytical results are in good agreement with multidimensional particle-in-cell simulations performed with OSIRIS. Relevance of current study to recent and future experiments on fireball beams is also addressed

Momentum space properties from coordinate space electron density

Electron density and electron momentum density, while independently tractable experimentally, bear no direct connection without going through the many-electron wave function. However, invoking a variant of the constrained-search formulation of density functional theory, we develop a general scheme (valid for arbitrary external potentials) yielding decent momentum space properties, starting exclusively from the coordinate space electron density. Numerical illustration of the scheme is provided for the closed-shell atomic systems He, Be and Ne and for $1s^1~2s^1$ singlet electronic excited state for Helium by calculating the Compton profiles and the $$ expectation values derived from given coordinate space electron densities.Comment: 4 pages, 1 figur

Magnetically assisted self-injection and radiation generation for plasma based acceleration

It is shown through analytical modeling and numerical simulations that external magnetic fields can relax the self-trapping thresholds in plasma based accelerators. In addition, the transverse location where self-trapping occurs can be selected by adequate choice of the spatial profile of the external magnetic field. We also find that magnetic-field assisted self-injection can lead to the emission of betatron radiation at well defined frequencies. This controlled injection technique could be explored using state-of-the-art magnetic fields in current/next generation plasma/laser wakefield accelerator experiments.Comment: 7 pages, 4 figures, accepted for publication in Plasma Physics and Controlled Fusio

Magnetic control of particle-injection in plasma based accelerators

The use of an external transverse magnetic field to trigger and to control electron self-injection in laser- and particle-beam driven wakefield accelerators is examined analytically and through full-scale particle-in-cell simulations. A magnetic field can relax the injection threshold and can be used to control main output beam features such as charge, energy, and transverse dynamics in the ion channel associated with the plasma blowout. It is shown that this mechanism could be studied using state-of-the-art magnetic fields in next generation plasma accelerator experiments.Comment: 10 pages, 3 figure

Higher order antibunching is not a rare phenomenon

Since the introduction of higher order nonclassical effects, higher order squeezing has been reported in a number of different physical systems but higher order antibunching is predicted only in three particular cases. In the present work, we have shown that the higher order antibunching is not a rare phenomenon rather it can be seen in many simple optical processes. To establish our claim, we have shown it in six wave mixing process, four wave mixing process and in second harmonic generation process.Comment: 6 pages, no figure, Latex 2

Prevalence of G6PD deficiency versus oxidizing drugs: a survey in the tertiary care hospital

Background: G6PD deficiency is distributed worldwide including India and is involved in accidental hemolysis and anemia by inadvertent use of oxidizing drugs. Awareness of community wise occurrence of G6PD deficiency can help in screening beforehand.Methods: On 150 community wise classified, non-anemic, non- hemolysed (in recent past) visitors of pathological laboratory attached to C U Shah Medical College, Surendranagar, Gujarat, Crayman’s hemoglobin colorimetric kit (item no 700540) was used to estimate normal or below normal status of G6PD.Results: 10 people (6.6% of population) were found deficient – 7 (4 male + 3 female) from Harijan community, 2 (1 male + 1 female) from Rabbari community and 1 (1 male + 0 female) from Lohana community.Conclusions: While applying oxidizing drugs in a person of Harijan community (prevalence 7 out of total 26, i.e. 27%), extra caution is required, esp. if a person otherwise vulnerable (e.g. alcoholic). For other less represented communities, larger stratified sampling is required

Global genetic variation of select opiate metabolism genes in self-reported healthy individuals

CYP2D6 is a key pharmacogene encoding an enzyme impacting poor, intermediate, extensive and ultrarapid phase I metabolism of many marketed drugs. The pharmacogenetics of opiate drug metabolism is particularly interesting due to the relatively high incidence of addiction and overdose. Recently, trans-acting opiate metabolism and analgesic response enzymes (UGT2B7, ABCB1, OPRM1 and COMT) have been incorporated into pharmacogenetic studies to generate more comprehensive metabolic profiles of patients. With use of massively parallel sequencing, it is possible to identify additional polymorphisms that fine tune, or redefine, previous pharmacogenetic findings, which typically rely on targeted approaches. The 1000 Genomes Project data were analyzed to describe population genetic variation and statistics for these five genes in self-reported healthy individuals in five global super- and 26 sub-populations. Findings on the variation of these genes in various populations expand baseline understanding of pharmacogenetically relevant polymorphisms for future studies of affected cohorts.Peer reviewe

Semi-Mechanized Harvesting Solutions for Cultivated Fodder Crops

In case of harvesting and threshing, the level of mechanization in India is 60-70 per cent for wheat and rice and less than five per cent for other crops (Mehta et al., 2014) that include fodder also. Herrmann et al.(2011) established that overall area capacities of machine decreased the by 4-24 per cent on taking finer chopping length of 4-6 mm compared to common chopping length of 8-10 mm in the ensiling chain of maize - establishing that finer work in ensiling commands less capacities and higher input costs. Since there is a strong correlation between effective field capacity and both crop yield and field area (Amiama et al., 2008), it is advisable to go for appropriate machine for fodder harvesting depending on the requirement of crop and field. Semi-automatic machines provide comparatively low cost workable solution in such conditions. In semi-mechanized harvesting of fodder, cutting of crop is done by machine and subsequent operations of collection, gathering, feeding to chaffing machines and feeding to animals are done manually. Such machines are discussed here

Study of Serum Lactate Dehydrogenase and Gamma-Glutamyl Transpeptidase in Breast Cancer Patients Receiving Chemotherapy.

Breast cancer (BC) is the most common type of cancer worldwide, being a major cause of morbidity in female. In Nepal it is the second most common type of cancer among females of perimenopausal age group. More than one quarter of the BC diagnosed in young Nepalese female, with familial history of breast cancer, early pregnancy, longer lactation and estrogen exposure and often with tumors showing aggressive biological behaviors. Anthracyclines (Doxorubicin) based treatment regime were reported to cause cardiotoxicity by increasing intramyocardial free radical production, lipid alterations and decreasing antioxidant level. Oxidative stress involving cellular reactive oxygen species (ROS) production is widely accepted mechanism but the molecular basis of chemotherapy induced organ toxicity remains highly controversial. An increased rate of metabolism and oxidative stress results rapid turnover of cancer cells that modulates the enzyme level in blood circulation. Serum LDH and GGT level correlates with tumor burden, metastatic character of BC and intensity of organtoxicity. The aim of our study is to evaluate the serum level of LDH and GGT in BC patients receiving chemotherapy and correlate these enzyme levels with different stages of BC. A total number of 150 subjects were included in the study, comprising 90 histopathologically confirmed 24 to 76 years aged patients of different breast cancer stages, receiving at least 3 cycles of 5-Fluorouracil, Adriamycin and Cyclophosphamide (FAC) chemotherapy. Sixty age- matched healthy women were enrolled as controls. Blood samples from each individual was collected after informed consent and analysed for serum LDH and GGT levels using standard biochemical methods. Data were analyzed using student's paired 't' test, Pearson correlation test and ANOVA. Serum LDH and GGT levels were significantly (p<0.001) increased in BC patients as compared to control group. When all 4 stages of BC were compared to control group, LDH and GGT showed steady and progressive increase in the activities of these enzymes from stage I-IV. The study concludes that serum LDH and GGT may be sensitive, specific and cost effective biomarkers in early diagnosis of breast cancer, assessing cancer prognosis and response to treatment