Energy Controlled Edge Formation for Graphene Nano Ribbons

On the basis of first principles calculations, we report energy estimated to cut a graphene sheet into nanoribbons of armchair and zigzag configurations. Our calculations show that the energy required to cut a graphene sheet into zigzag configuration is higher than that of armchair configuration by an order of 0.174 eV. Thus, a control over the threshold energy might be helpful in designing an experiment for cutting a graphene sheet into smooth edged armchair or zigzag configurations

Edge Configurational Effect on Band Gaps in Graphene Nanoribbons

In this Letter, we put forward a resolution to the prolonged ambiguity in energy band gaps between theory and experiments of fabricated graphene nanoribbons (GNRs). Band structure calculations using density functional theory are performed on oxygen passivated GNRs supercells of customized edge configurations without disturbing the inherent sp2 hybridization of carbon atoms. Direct band gaps are observed for both zigzag and armchair GNRs, consistent with the experimental reports. In addition, band gap values of GNRs scattered about an average value curve for a given crystallographic orientation are correlated with their width on basis of the edge configurations elucidates the band gaps in fabricated GNRs. We conclude that edge configurations of GNRs significantly contribute to band gap formation in addition to its width for a given crystallographic orientation, and would play a crucial role in band gap engineering of GNRs for future research works on fabrication of nanoelectronic devices.Comment: 5 pages, 6 figure

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

Malaria in school-age children in Africa: an increasingly important challenge.

School-age children have attracted relatively little attention as a group in need of special measures to protect them against malaria. However, increasing success in lowering the level of malaria transmission in many previously highly endemic areas will result in children acquiring immunity to malaria later in life than has been the case in the past. Thus, it can be anticipated that in the coming years there will be an increase in the incidence of both uncomplicated and severe malaria in school-age children in many previously highly endemic areas. In this review, which focuses primarily on Africa, recent data on the prevalence of malaria parasitaemia and on the incidence of clinical malaria in African school-age children are presented and evidence that malaria adversely effects school performance is reviewed. Long-lasting insecticide treated bednets (LLIN) are an effective method of malaria control but several studies have shown that school-age children use LLINs less frequently than other population groups. Antimalarial drugs are being used in different ways to control malaria in school-age children including screening and treatment and intermittent preventive treatment. Some studies of chemoprevention in school-age children have shown reductions in anaemia and improved school performance but this has not been the case in all trials and more research is needed to identify the situations in which chemoprevention is likely to be most effective and, in these situations, which type of intervention should be used. In the longer term, malaria vaccines may have an important role in protecting this important section of the community from malaria. Regardless of the control approach selected, it is important this is incorporated into the overall programme of measures being undertaken to enhance the health of African school-age children

Evaluation of Anthelmintic Activity on Cestode Parasite Raillietina tetragona by Using Silver Nanoparticles of Cucurbita maxima Seeds and Punica granatum peel

A significant field of nanotechnology is the green synthesis of nanoparticles. In order to ascertain the effectiveness of synthesized silver nanoparticles (AgNps) against the parasite Raillietina tetragona, the current study focuses on the biosynthesis method of producing silver nanoparticles using biological compounds and evaluating their anthelmintic activities using aqueous and ethanolic extracts of Cucurbita maxima seeds and Punica granatum peel. Silver nanoparticles from 1 mM AgNO3 solution and the Soxhlet apparatus are used to prepare the ethanolic extract of P. granatum peel and C. maxima seeds through aqueous and ethanolic extract. The sample turning brown indicates that silver nanoparticles have been produced. The UV-vis spectrophotometer and Fourier transform infrared (FTIR) spectrophotometer are used to characterize these produced silver nanoparticles. Different concentrations of Aqueous, Ethanolic, silver nanoparticles extract of C. maxima seeds and P. granatum peel are 2.5 mgml-1, 5 mgml-1, and 10 mgml-1 were treated against cestode parasite R. tetragona. Albendazole is taken as standard and distilled water as control. A lower concentration, 2.5 mgml-1 shows a slow paralytic and death rate of cestode worms compared to those in the higher concentration 10 mgml-1. The study results showed that the death of the worms is dose-dependent manner. Results indicate that compared to the standard drug Albendazole, C. maxima seeds and P. granatum peel extracts are more effective Anthelmintic for chicken. After performing Anthelmintic activity on R. tetragona using both extracts time taken for the death of parasites in C. maxima seed extract is shorter than P. granatum peel. Based on the data observed, this study was concluded that C. maxima seed extract is more effective anthelmintic for chicken than P. granatum peel extract

A Novel Algorithm for AODV to Enhance the Efficiency and Performance of the MANET

Network security and performance are significant topics discussed in academic and Industrial research. Every application depends on the performance and efficiency of the network. Routing protocols and mechanisms play an essential role. AODV routing protocol is considered standard in many aspects, primarily due to the increasing efficiency requirements in various applications. There are different approaches in the literature trying to improve the performance. Some studies considered multiple parameters such as density and mobility of the data nodes. This research study evaluates the two critical parameters that contribute to the overall efficiency and performance of the network – throughput and route resilience. A new version of enhanced AODV is proposed in this paper that uses an iterative approach to check for each parameter and adjust the values accordingly until the required threshold level of efficiency is reached. The solution is explained in different categories pertaining to each network parameter. The proposed algorithm is simulated on a network tool, and the results show that the enhanced version of the routing protocol is promising and can be further extended to introduce new modes for higher efficiency and lower power consumption

Impact and Perception of Students towards Online Learning during COVID-19

Aim: This study aims to analyse the impact and perception of students towards online learning during Covid-19 and the constraints faced by the students. Study Design: Ex post facto research design. Place and Duration of the Study: the present study was conducted among UG,PG & PhD students of TNAU. The study was conducted during January and February month 2021. Methodology: 50 students were randomly selected and interviewed using a pre tested interview schedule to study the impact and perception of students towards online learning during Covid-19 and the constraints faced by them. Background of the Study: The concept of e-learning can be termed as a network enabled transfer of skills and knowledge, and the delivery of education is made to a large number of recipients at the same or different times. Though e- learning resources and online mode of learning was made available long back, it became popular and inevitable only after the storm created by the pandemic, courtesy COVID-19. It has persisted to force and push the students and teachers towards online learning environment for the past one year and continues to garner importance in the current scenario. Though Online-learning mode emerged as a better alternative to the classroom situation, it has its own pros and cons as perceived by the participating students and teachers. Since, it is becoming a more common method of instruction, it is important to assess its impact among the stakeholders and to assess the existing gaps. This impact study involving perception of the students regarding online learning can serve as a resource to identify the areas for improvement and betterment of learning situation