Nature and role of root exudates: Efficacy in bioremediation

Root exudate is one of the ways for plant communication to the neighboring plant and adjoining of microorganisms present in the rhizosphere of the root. The chemicals ingredients of the root exudates are specific to a particular plant species and also depend on the nearby biotic and abiotic environment. The chemical ingredient exuded by plant roots include amino acids, sugars, organic acids, vitamins, nucleotides, various other secondary metabolites and many other high molecular weight substances as primarily mucilage and some unidentified substances. Through the exudation of a wide variety of compounds, roots may regulate the soil microbial community in their immediate vicinity, cope with herbivores, encourage beneficial symbioses, change the chemical and physical properties of the soil and inhibit the growth of competing plant species. Root exudates mediate various positive and negative interactions like plant-plant and plant-microbe interactions. The present review has been undertaken to examine the possible role of root exudates on the removal of the polluted matter and nourishing the neighboring microorganisms present in the rhizosphere of the root.Key words: Rhizosphere, root exudates, bioremediation, rhizoremediation

Therapeutic effect of hydroethanolic extract of Trianthema portulacastrum L. against N-Nitroso-N-Methylurea-induced mammary tumors in Wistar rats

406-415This study evaluated the therapeutic action of hydroethanolic extract of Trianthema portulacastrum L. (TPE) on N-nitroso-N-methylurea (NMU)-induced mammary tumors in Wistar rats. A hydroethanolic was prepared and subjected to qualitative and quantitative phytochemical screening. After acclimatization, Wistar rats were divided into 4 groups of 6 rats each: Group A (vehicle control), Group B (TPE control), Group C (TPE treatment) and group D (NMU control). NMU (50 mg/kg body weight) was injected intraperitoneally at 50, 80 and 110 days of age. After the induction of palpable tumors, the rats were administered 200 mg/kg bw of TPE by oral gavage for 2 months. The treatment with TPE significantly (pin vivo therapeutic action of TPE extract on NMU-induced mammary tumors. TPE exhibited antitumor activity through its antiproliferative, antiangiogenic, pro-apoptotic, and estrogen receptor-modulatory properties

Short Communication: A qualitative assessment of food security in an internally displaced persons camp in Kenya

The 2007/08 post-election violence in Kenya resulted in the displacement of an estimated 600 000 people. Current published research suggests that many of these internally displaced persons (IDPs) continue to have issues accessing basic needs, including food and water, impacting morbidity and mortality. This study aimed to assess food security and access to cooking fuel and water within an internally displaced persons’ (IDP) camp in Kenya. It was designed as a descriptive, qualitative study involving semi-structured interviews with members of households residing in the IDP camp. Participants were recruited through respondent-driven sampling using a network of coupons. Semi-structured interviews were utilised to determine key issues associated with the attainment of food security, access to cooking fuel and water among resident IDPs, targeting male household heads. Interview structure was based on framework for assessment of food security provided by the International Federation of the Red Cross. Recorded interviews then underwent thematic analysis using NVivo 10 (QSR International, Melbourne, Victoria). A total of 15 semi-structured interviews were completed with men at the camp, aged between 18 and 53. Thematic analysis shows that key elicited concerns regarding food security included lack of capital for agriculture, lack of dietary diversity, seasonal insecurity and anxiety about the future. Access to water was limited to a single borehole located within the camp. Few reliable and safe sources could be identified for cooking fuel. Thus, internally displaced persons residing at this camp continue to experience significant food insecurity. Despite being allocated land for agriculture, they lack capital for investment in agriculture and access to local food markets. Access to water and cooking fuel is limited and a source of significant concern. Initiatives to improve food security delivered through government and non-government programs are necessary to minimise the significant impact of such food insecurity on mental health and disease profiles as reported in other IDP settings.Key words: Internally displaced persons, Kenya, Food security, Qualitative study, Nutritio

Library and Information Science Education in India: Growth, Development, Problems and Prospects

The purpose of the study is to explore the history and growth of the Indian LIS education system, its sustainability, and describe a critical review of recent UGC proposed Learning Outcomes-based Curriculum Framework (LOCF) syllabi. The formal LIS education which was started before independence with few universities currently witnessed a phenomenal growth of LIS departments/schools in the county. The structured questionnaire and survey methods were used to collect relevant data about availability of various courses and supplemented by searching websites and personal contacts. The findings of the study indicates that that 237 universities/colleges/ polytechnic institutes and professional associations found offering LIS education from six months certificate course to a doctoral research program. The survey revealed that at present B.A. (Hons.), B.Sc. (H), Dip. in LIS (3 years), CLIS, BLIS, MLIS, MLIS (two years integrated), PGDLAN, M. Phil., Ph.D., and D.Litt. courses are available in 31 states and UT of Indian universities/colleges in Library and Information Science. The study also finds that during the span of 20 years (2001-2020) 105 LIS departments came into existence primarily in private universities and colleges. The latest UGC proposed LOCF syllabi for BLIS also examined its acceptability and sustainability as a uniform model curriculum framework for the LIS departments in India, In addition, the study describes key issues, challenges and recommendations to enhance LIS education scenario

Bibliometric Study of Publications in Conference Proceedings of SRFLIS Summit during 2014-2019

The purpose of the study is to conduct bibliometric analysis of the research articles of SRFLIS Summit- International Conferences held during the year 2014-2019 and investigate the various dimensions of bibliometric study. The paper conducts bibliometric analysis of 220 articles which were published in the form of conference papers during the covered period. The study evaluates the various aspects of published conference articles of SRFLIS Summit. The study highlights the chronological distribution of papers, authorship pattern, geographical distribution, and affiliation of authors, citation pattern and length of articles. The results explore that the majority of the contributions by two authors. It is observed that a total of 2720 citations counted to the contributions and most cited documents are journal articles. The analysis of countries found that majority of contributions are from India and authors from New Delhi published maximum papers. The study evaluates the publication trends and has important implications for scholars and researcher

Designing Efficient Phase-Gradient Metasurfaces for Near-Field Meta-Steering Systems

We investigate the aptness of various $4^{th}$ order (90°) rotationally symmetric phase-transforming cells for the upper phase-gradient metasurface, which always receives an oblique incidence wave from the lower metasurface in a Near-Field Meta-Steering system. A comprehensive study on the behavior of various phase-transforming cells and corresponding supercells when a rotating oblique plane wave impinges on them is presented. First, we select the supercell with high transmission in the desired output Floquet modes, for both TE and TM input modes, when an oblique incidence wave is rotated. The selected supercell is then optimized using Floquet analysis in conjunction with particle swarm optimization (PSO). All the undesired modes are successfully suppressed below -32 dB in the optimized supercell, and the predicted broadside radiation pattern is free of spurious grating lobes. A Near-Field Meta-Steering system with an aperture diameter of $7.3\lambda _{0}$ (110mm @ 20 GHz) is presented. It has a pair of optimized phase-gradient metasurfaces and a dipole antenna array. A maximum peak directivity of 24.2 dB is achieved when the beam is in the broadside direction. The proposed steering system is capable of scanning a conical range with an apex angle of 126° when a 6 dB reduction in peak directivity is allowed. For a 3 dB variation in the peak directivity, the corresponding apex angle is 103°

Allostatic load as a predictor of grey matter volume and white matter integrity in old age: The Whitehall II MRI study

The allostatic load index quantifies the cumulative multisystem physiological response to chronic everyday stress, and includes cardiovascular, metabolic and inflammatory measures. Despite its central role in the stress response, research of the effect of allostatic load on the ageing brain has been limited. We investigated the relation of mid-life allostatic load index and multifactorial predictors of stroke (Framingham stroke risk) and diabetes (metabolic syndrome) with voxelwise structural grey and white matter brain integrity measures in the ageing Whitehall II cohort (N = 349, mean age = 69.6 (SD 5.2) years, N (male) = 281 (80.5%), mean follow-up before scan = 21.4 (SD 0.82) years). Higher levels of all three markers were significantly associated with lower grey matter density. Only higher Framingham stroke risk was significantly associated with lower white matter integrity (low fractional anisotropy and high mean diffusivity). Our findings provide some empirical support for the concept of allostatic load, linking the effect of everyday stress on the body with features of the ageing human brain

Controlling the Most Significant Grating Lobes in Two-Dimensional Beam-Steering Systems with Phase-Gradient Metasurfaces

© 2019 IEEE. High-directivity antenna systems that provide 2-D beam steering by rotating a pair of phase-gradient metasurfaces (PGMs) in the near field of a fixed-beam antenna, hereafter referred to as near-field meta-steering systems, are efficient, planar, simple, short, require less power to operate, and do not require antenna tilting. However, when steering the beam, such systems generate undesirable dominant grating lobes, which substantially limit their applications. Optimizing a pair of these metasurfaces to minimize the grating lobes using standard methods is nearly impossible due to their large electrical size and thousands of small features leading to high computational costs. This article addresses this challenge as follows. First, it presents a method to efficiently reduce the strength of 'offending' grating lobes by optimizing a supercell using Floquet analysis and multi-objective particle swarm optimization. Second, it investigates the effects of the transmission phase gradient of PGMs on radiation-pattern quality. It is shown that the number of dominant unwanted lobes in a 2-D beam-steering antenna system and their levels can be reduced substantially by increasing the transmission phase gradient of the two PGMs. This knowledge is then extended to 2-D beam-steering systems, where we demonstrate how to substantially reduce all grating lobes to a level below-20 dB for all beam directions, without applying any amplitude tapering to the aperture field. When steering the beam of two meta-steering systems with peak directivities of 30.5 and 31.4 dBi, within a conical volume with an apex angle of 96°, the variation in directivity is 2.4 and 3.2 dB, respectively. We also demonstrate that beam-steering systems with steeper gradient PGMs can steer the beam in a wider range of directions, require less mechanical rotation of metasurfaces to obtain a given scan range, and their beam steering is faster. The gap between the two metasurfaces in a near-field meta-steering system can be reduced to one-eighth of a wavelength with no significant effect on pattern quality

Low melt alloy blended polyalcohol as solid-solid phase change material for energy storage: an experimental study

Centre for Engineering Research and Development; UKIERI-DS