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Therapeutic Properties of Trichopus zeylanicus Subsp. travancoricus, a Rare, Endangered Medicinal Plant in South India: A Review

Trichopus zeylanicus subsp. travancoricus, belonging to the family Trichopodaceae, is a small herbaceous plant exclusively present in Western Ghats of South India. The indigenous tribal community in Western Ghats traditionally use this plant for getting instant energy to combat fatigue. Recent pharmacological studies have revealed that besides its antifatigue property, this plant possess many medicinal properties such as anti-oxidant, anti-inflammatory, anti-stress, immunomodulatory, antidiabetic, aphrodisiac, antihyperlipidemic, antitumor, antiulcer, antimicrobial and hepatoprotective activity. This article comprehensively review the results of pharmacological studies so far done in this plant and emphasizes perspectives that warrant future research to explore its full pharmacological potential

Implementation of a modified wireless sensor network MAC protocol for critical environments

A Wireless Sensor Network (WSN) is a network of many nodes. These nodes are equipped with sensors which communicate wirelessly using techniques for radio frequency transmission. This network helps to measure and record the physical environment variables and to forward these results to a central location known as a sink. As WSN nodes are only supplied by a battery, the primary challenge is to reduce the energy consumption. The MAC layer is responsible for the establishment of a reliable and efficient communication link between WSN nodes and is responsible for energy waste. The newly proposed MAC protocol in this paper uses an improved variant of CSMA which implements weak signal detection (WSD). This technique enables dividing collisions from weak signals and takes appropriate decisions to reduce energy consumption. The CSMA/WSD protocol is presented as a flowchart and implemented in OMNeT++ by using the MiXiM framework structure. Implementation tests are performed to prove the validity of the implemented protocol in different scenarios. Different simulation scenarios show that this protocol offers a higher throughput, a smaller mean backoff time, and less average delay in critical environments

Open Source Software Use in Indian Libraries: A Survey.

The term “Open Source” is a trending topic at present among LIS professionals in India. Open Source applications in libraries progressed as a matter of serious discussion among the library professionals. Stakeholders of Indian Library sector now a day’s realize the advantages of embracing Open Source softwares. This Paper attempts to find out the usage of Open Source software in Indian Libraries. It is found that there is a positive attitude from the part of library professionals towards the acceptance of Open Source softwares.The study also underscores the necessity of orientation Programmes for making Professionals more familiar for adoption of Open Source software in libraries

Voronoi diagram based simulation and experimental validation of austenite in C22 and C35 steels

This paper examines the ability of power Voronoi diagram assisted simulation in microstructure modeling during heat treatment. A model is developed for predicting fraction of austenite evolved during continuous heating of steel to austenite range, by integrating geometrical features of power Voronoi diagram and classical nucleation theory. From the simulation results, it is possible to predict the transformed fraction. The simulation results are validated using experiments conducted on two varieties of steels. The maximum error obtained is 2.08%. Thus, power Voronoi assisted simulation can be considered as an effective tool in modeling microstructure evolution during austenitization

Open Source Software Use in Indian Libraries: A Survey.

The term “Open Source” is a trending topic at present among LIS professionals in India. Open Source applications in libraries progressed as a matter of serious discussion among the library professionals. Stakeholders of Indian Library sector now a day’s realize the advantages of embracing Open Source softwares. This Paper attempts to find out the usage of Open Source software in Indian Libraries. It is found that there is a positive attitude from the part of library professionals towards the acceptance of Open Source softwares.The study also underscores the necessity of orientation Programmes for making Professionals more familiar for adoption of Open Source software in libraries

Single-molecule photochemical reactions of Auger-ionized quantum dots

Photoinduced electron transfer in donor-acceptor systems composed of quantum dots (QDs) and electron donors or acceptors is a subject of considerable recent research interest due to the potential applications of such systems in both solar energy harvesting and degradation of organic pollutants. Herein, we employed single-molecule imaging and spectroscopy techniques for the detection of photochemical reactions between 1,4-diaminobutane (DAB) and CdSe/ZnS single QDs. We investigated the reactions by analyzing photoluminescence (PL) intensity and lifetime of QDs at ensemble and single-molecule levels. While DAB was applied to single QDs tethered on a cover slip or QDs dispersed in a solution, PL intensity of QD continuously decreased with a concomitant increase in the PL lifetime. Interestingly, these changes in the PL properties of QD were predominant under high-intensity photoactivation. We hypothesize that the above changes in the PL properties surface due to the transfer of an electron from DAB to Auger-ionized QD followed by elimination of a proton from DAB and the formation of a QD-DAB adduct. Thus, a continuous decrease in the PL intensity of QDs under high-intensity photoactivation is attributed to continuous photochemical reactions of DAB with single QDs and the formation of QD-(DAB)n adducts. We believe that detection and analysis of such photochemical reactions of single QDs with amines will be of considerable broad interest due to the significant impact of photoinduced electron transfer reactions in energy management and environmental remediation

Multiple evolutionary trajectories have led to the emergence of races in <em>Fusarium oxysporum</em> f. sp. <em>lycopersici</em>

Race 1 isolates of Fusarium oxysporum f. sp. lycopersici (FOL) are characterized by the presence of AVR1 in their genomes. The product of this gene, Avr1, triggers resistance in tomato cultivars carrying resistance gene I. In FOL race 2 and race 3 isolates, AVR1 is absent, and hence they are virulent on tomato cultivars carrying I. In this study, we analyzed an approximately 100-kb genomic fragment containing the AVR1 locus of FOL race 1 isolate 004 (FOL004) and compared it to the sequenced genome of FOL race 2 isolate 4287 (FOL4287). A genomic fragment of 31 kb containing AVR1 was found to be missing in FOL4287. Further analysis suggests that race 2 evolved from race 1 by deletion of this 31-kb fragment due to a recombination event between two transposable elements bordering the fragment. A worldwide collection of 71 FOL isolates representing races 1, 2, and 3, all known vegetative compatibility groups (VCGs), and five continents was subjected to PCR analysis of the AVR1 locus, including the two bordering transposable elements. Based on phylogenetic analysis using the EF1-α gene, five evolutionary lineages for FOL that correlate well with VCGs were identified. More importantly, we show that FOL races evolved in a stepwise manner within each VCG by the loss of function of avirulence genes in a number of alternative ways. IMPORTANCE Plant-pathogenic microorganisms frequently mutate to overcome disease resistance genes that have been introduced in crops. For the fungus Fusarium oxysporum f. sp. lycopersici, the causal agent of Fusarium wilt in tomato, we have identified the nature of the mutations that have led to the overcoming of the I and I-2 resistance genes in all five known clonal lineages, which include a newly discovered lineage. Five different deletion events, at least several of which are caused by recombination between transposable elements, have led to loss of AVR1 and overcoming of I. Two new events affecting AVR2 that led to overcoming of I-2 have been identified. We propose a reconstruction of the evolution of races in FOL, in which the same mutations in AVR2 and AVR3 have occurred in different lineages and the FOL pathogenicity chromosome has been transferred to new lineages several times