High harmonic generation from Bloch electrons in solids

We study the generation of high harmonic radiation by Bloch electrons in a model transparent solid driven by a strong mid-infrared laser field. We solve the single-electron time-dependent Schr\"odinger equation (TDSE) using a velocity-gauge method [New J. Phys. 15, 013006 (2013)] that is numerically stable as the laser intensity and number of energy bands are increased. The resulting harmonic spectrum exhibits a primary plateau due to the coupling of the valence band to the first conduction band, with a cutoff energy that scales linearly with field strength and laser wavelength. We also find a weaker second plateau due to coupling to higher-lying conduction bands, with a cutoff that is also approximately linear in the field strength. To facilitate the analysis of the time-frequency characteristics of the emitted harmonics, we also solve the TDSE in a time-dependent basis set, the Houston states [Phys. Rev. B 33, 5494 (1986)], which allows us to separate inter-band and intra-band contributions to the time-dependent current. We find that the inter-band and intra-band contributions display very different time-frequency characteristics. We show that solutions in these two bases are equivalent under an unitary transformation but that, unlike the velocity gauge method, the Houston state treatment is numerically unstable when more than a few low lying energy bands are used

Draft bills and research reports on: reducing judicial corruption and child labor in Nepal

These two draft bills and accompanying research report comprise the work of two teams of Nepali officials from Nepal's Ministry of Law and Justice who prepared them in the context of the Boston University School of Law Program on Legislative Drafting for Democratic Social Change. They attended that Program as part of a larger Ministry of Law and Justice Program, funded by the United Nations Development Program (UNDP), to strengthen Nepal's legal framework and the Rule of Law. Using the bills and reports as case studies, the four officials aimed to learn legislative theory, methodology and techniques. The Ministry had assigned them, on their return to Nepal, to play a significant role in institutionalizing an on-going learning process to strengthen Nepali drafters' capacity to prepare the effectively implementable legislation necessary to ensure good governance and development

Agro-morphological Diversity of High Altitude Bean Landraces in the Kailash Sacred Landscape of Nepal

Many varieties of bean are widely grown across diverse agro-ecological zones in Nepal. And opportunities exist for improving the crops and enhancing their resilience to various biotic and abiotic stressors. In this context, an experiment was conducted from June to October 2016 in Khar VDC of Darchula district to study the phenotypic traits of nine landraces of bean (Phaseolus vulgaris L.). The bean landraces were planted using randomized complete block design in three sites (Dhamidera, Dallekh and Sundamunda villages), with three replications in each site for their comparative analysis. The study considered the following phenotypic traits: days to emergence, days to 50% flowering, days to 90% pod maturity, number of nodes, pod length, pod width, number of pods, number of seeds per pod and weight and grain yield for 100 seeds. Kruskal-Wallis test showed significant differences in the landraces both within and among locations. KA-17-08-FB and KA-17-04-FB were late  flowering (63 and 65 days respectively) compared to other landraces whereas KA-17-07-FB flowered earliest (within 42 days). In all three sites, three landraces namely KA-17-07-FB, KA-17-04-FB and KA-17-06-FB were found to be relatively more resistant to pest and diseases than other landraces. Eight out of nine landraces in Dhamidera and Dallekh villages and seven out of nine in Sundamunda village produced seeds greater than 1.0 t/ha. Among the nine varieties KA-17-02-FB was the highest yielding variety, with an average yield of 3.8 t/ha. This study is useful for identifying suitable landraces for future promotion based on their maturity, grain yield, diseases resistance and other qualitative and quantitative characteristics

Assessing Migration and Remittance Status and Its Effect on Maize Production in Nepal

Outmigration has been considered a major issue in agricultural production of Nepal. The study aimed to assess migration and remittance status and its effect on maize production. Altogether 682, both migrated and non-migrated households were selected using proportionate random sampling from six representative districts covering four provinces and all ecological domains of Nepal. Primary data were collected through households' survey and focus group discussion using structured and pretested interview schedule. The results showed that 26 percent of households have at least one member living abroad for a job opportunity. Most of the migration was male-centric and Chitwan district ranked first among study districts on migration status. About 43 percent of households received more than two hundred thousand annually as remittance and mostly they used that money in household consumption followed by education and loan repayment. Around 54 percent of households agreed that they were using remittances in maize farming mainly for purchasing chemical fertilizer and improved seed. The use of remittance income in mechanization such as buying/using of corn sheller and power tiller was comparatively very less. The results showed insignificant maize productivity but the fallow land holdings of the migrated household were significantly higher than non-migrating households. The issue of migration and fallow land holdings in maize has become an emerging concern to development worker and policy makers. Therefore, the introduction of efficient maize production system along with value addition program that linked with market targeting youth manpower is an urgent need for effective utilization of fallow land. Moreover, such opportunity also provides an avenue to the productive investment of remittance

Analysis of Chlorophyll Content and Its Correlation with Yield Attributing Traits on Early Varieties of Maize (Zea Mays L.)

Chlorophyll has direct roles on photosynthesis and hence closely relates to capacity for photosynthesis, development and yield of crops. With object to explore the roles of chlorophyll content and its relation with other yield attributing traits a field research was conducted using fourteen early genotypes of maize in RCBD design with three replications. Observations were made for Soil Plant Analysis Development (SPAD) reading, ear weight, number of kernel row/ear, number of kernel/row, five hundred kernel weight and grain yield/hectare and these traits were analyzed using Analysis of Variance (ANOVA) and correlation coefficient analysis. SPAD reading showed a non-significant variation among the genotypes while it revealed significant correlation with no. of kernel/row, grain yield/hectare and highly significant correlation with no. of kernel row/ear and ear weight which are the most yield determinative traits. For the trait grain yield/ha followed by number of kernel row/ear genotype ARUN-1EV has been found comparatively superior to ARUN-2 (standard check). Grain Yield/hectare was highly heritable (>0.6) while no. of kernel / row, SPAD reading, ear weight, number of kernel row/ear were moderately heritable (0.3-0.6). Correlation analysis and ANOVA revealed ARUN-1EV, comparatively superior to ARUN-2 (standard check), had higher SPAD reading than mean SPAD reading with significant correlation with no. of kernel/row, no. of kernel row/ear, ear weight and grain yield/ha which are all yield determinative traits . This showed positive and significant effect of chlorophyll content in grain yield of the maize.Journal of Maize Research and Development (2015) 1(1):134-145DOI: http://dx.doi.org/10.5281/zenodo.3426