208 research outputs found

    An Analysis of LoRa Low Power Technology and its Applications

    Get PDF
    The number of Internet of Things (IoT) devices has exponentially increased in the last decade. With the increase in these devices, there is a necessity to effectively connect and control these devices remotely. Cellular technologies cannot handle this demand since they are not cost effective and easy to deploy. This is where LoRa technology comes handy. LoRa is long-range, low-power, low cost technology that supports internet of things applications. LoRa has many advantages in terms of capacity, mobility, battery lifetime and cost. It uses the unlicensed 915MHz ISM band and can be easily deployed. This research is focused on setting up a LoRa base-station to observe the functionality, reliability and limitations of the LoRa protocol. As a first step, the MultiTech gateway and node was set up and the IBM Watson (IBM BlueMix) IOT platform was used to transmit and receive messages. Information like temperature, pressure, accelerometer reading and location in terms of latitude and longitude could be sent to the MultiTech Conduit (gateway/concentrator) by simply sending a message from the mDot end device. Different sensors can be incorporated into the current setup and the functionality of the node can be enhanced by using Node-Red platform that allows programming the devices in use. Future work will involve setting up a base station using the OpenChirp infrastructure with LoRaBug (node) and the OpenChirp Gateway

    Quantifying the benefits of SPECint distant parallelism in simultaneous multithreading architectures

    Get PDF
    We exploit the existence of distant parallelism that future compilers could detect and characterise its performance under simultaneous multithreading architectures. By distant parallelism we mean parallelism that cannot be captured by the processor instruction window and that can produce threads suitable for parallel execution in a multithreaded processor. We show that distant parallelism can make feasible wider issue processors by providing more instructions from the distant threads, thus better exploiting the resources from the processor in the case of speeding up single integer applications. We also investigate the necessity of out-of-order processors in the presence of multiple threads of the same program. It is important to notice at this point that the benefits described are totally orthogonal to any other architectural techniques targeting a single thread.Peer ReviewedPostprint (published version

    ENGINEERED IN VITRO BREAST CANCER MODELS SHOW PHENOTYPIC DIFFERENTIATION CHARACTERISTICS OF EARLY VS. LATE-STAGE DISEASE

    Get PDF
    Cancer drug discovery and development is challenged by poor prediction of drug responses in in vitro disease models. Results from clinical trials suggest that just 5% of drugs tested are successful in patients. Currently used disease models such as two-dimensional (2D) cell monolayers and in vivo animal models fail to recapitulate the human tumor microenvironment. Further, disease progression from the non-invasive to metastatic stage needs models that can recapitulate each stage. Hence, there is an unmet need to develop three-dimensional (3D) models that capture natural tumor progression for better understanding of disease biology as well as screening of drug regimens acting on different disease stages. In this work, we have characterized 3D breast microtumors ranging from 150 to 600 μm diameters using non-invasive T47D cells with precise control over physicochemical microenvironmental factors. In this study, we test the hypothesis that the size-controlled microtumors will exhibit differential biochemical features and drug response arising from unique molecular signatures created by variable tumor microenvironments. To test this hypothesis, we studied the physicochemical features such as hypoxia, reactive oxygen species, metabolic activity, and cell cycle status. Additionally, the expression of key regulators of growth/proliferation pathways in breast cancer progression such as estrogen receptor alpha (ER-α) and growth factor receptor/s was studied and efficacy of clinically used inhibitors such as 4-hydroxytamoxifen (4-OHT) was evaluated. The results indicated that large T47D microtumors (600 μm) exhibited traits of clinically advanced tumors such as collective cell migration, mesenchymal marker upregulation, loss of ER-α and endocrine resistance in contrast to the small microtumors (150 μm). Thus, the engineered in vitro models could successfully recapitulate phenotypic differentiation characteristics of early vs. late disease stage in the same non-invasive T47D cells just by precisely controlling the microtumor size, which further regulated the tumor microenvironmental factors. The large microtumors (600 μm) were found to resemble features of advanced stage breast cancer whereas the small microtumors (150 μm) recapitulated features of early stage breast cancer. Hence, such disease stage-specific microtumor models could help in the evaluation of crucial mechanisms in breast tumor progression correlated to tumor size and in the screening of therapeutic candidate/s

    Structure based de novo design of IspD inhibitors as anti-tubercular agents

    Get PDF
    Tuberculosis is one of the leading contagious diseases, caused by Mycobacterium tuberculosis. Despite improvements in anti-tubercular agents, it remains one of the most prevalent infectious diseases worldwide, responsible for a total of 1.6 million deaths annually. The emergence of multidrug resistant strains highlighted the need of discovering novel drug targets for the development of anti-tubercular agents. 2-C-methyl-D-erythritol-4-phosphate cytidyltransferase (IspD) is an enzyme involved in MEP pathway for isoprenoid biosynthesis, which is considered an attractive target for the discovery of novel antibiotics for its essentiality in bacteria and absence in mammals. In the present study, we have employed structure based drug design approach to develop novel and potent inhibitors for IspD receptor. To explore binding affinity and hydrogen bond interaction between the ligand and active site of IspD receptor, docking studies were performed. ADMET and synthetic accessibility filters were used to screen designed molecules. Finally, ten compounds were selected and subsequently submitted for the synthesis and in vitro studies as IspD inhibitors

    Sensitivity of Indian summer monsoon simulation to physical parameterization schemes in the WRF model

    Get PDF
    A set of 17 experiments, using various combinations of physical parameterization schemes in the Weather Research and Forecasting (WRF) model, were carried out to choose a combination suitable for simulating the Indian summer monsoon. The model experiments, forced with the ERA-Interim reanalysis data, were at 30 km horizontal resolution. The WRF model experiments were initialized on 1 May of each year and integrated until 30 September to cover the entire monsoon season for the years 1982 to 2013. The results indicate that the simulated Indian summer monsoon precipitation and 2 m air temperature are sensitive to the physical parameterization schemes in the WRF model and that choosing the correct combination of physical parameterization schemes is essential for simulating the Indian summer monsoon realistically. Our analysis shows that a model setup with the Kain-Fritsch cumulus scheme, a radiation package with the Dudhia shortwave and Rapid Radiative Transfer Model longwave schemes, the Yonsei State University planetary boundary layer scheme, the WRF Single-Moment 3-class microphysics scheme, the revised MM5 Monin-Obukhov surface layer scheme, and the Unified Noah land surface model is suitable for simulating the precipitation realistically. The model setup with a combination of these physical parameterization schemes was found to have smaller biases and root mean square errors in the simulated precipitation, along with a realistic simulation of intraseasonal and interannual variability of precipitation. The results of this study will be useful to researchers and forecasters using the WRF model to improve the Indian summer monsoon simulations/forecasts over the Indian region

    Molecular Rationale behind the Differential Substrate Specificity of Bacterial RND Multi-Drug Transporters

    Get PDF
    Resistance-Nodulation-cell Division (RND) transporters AcrB and AcrD of Escherichia coli expel a wide range of substrates out of the cell in conjunction with AcrA and TolC, contributing to the onset of bacterial multidrug resistance. Despite sharing an overall sequence identity of ~66% (similarity ~80%), these RND transporters feature distinct substrate specificity patterns whose underlying basis remains elusive. We performed exhaustive comparative analyses of the putative substrate binding pockets considering crystal structures, homology models and conformations extracted from multi-copy μs-long molecular dynamics simulations of both AcrB and AcrD. The impact of physicochemical and topographical properties (volume, shape, lipophilicity, electrostatic potential, hydration and distribution of multi-functional sites) within the pockets on their substrate specificities was quantitatively assessed. Differences in the lipophilic and electrostatic potentials among the pockets were identified. In particular, the deep pocket of AcrB showed the largest lipophilicity convincingly pointing out its possible role as a lipophilicity-based selectivity filter. Furthermore, we identified dynamic features (not inferable from sequence analysis or static structures) such as different flexibilities of specific protein loops that could potentially influence the substrate recognition and transport profile. Our findings can be valuable for drawing structure (dynamics)-activity relationship to be employed in drug design

    Recent Advances in Plasmonic Photocatalysis Based on TiO2 and Noble Metal Nanoparticles for Energy Conversion, Environmental Remediation, and Organic Synthesis

    Get PDF
    Plasmonic photocatalysis has emerged as a prominent and growing field. It enables the efficient use of sunlight as an abundant and renewable energy source to drive a myriad of chemical reactions. For instance, plasmonic photocatalysis in materials comprising TiO2 and plasmonic nanoparticles (NPs) enables effective charge carrier separation and the tuning of optical response to longer wavelength regions (visible and near infrared). In fact, TiO2-based materials and plasmonic effects are at the forefront of heterogeneous photocatalysis, having applications in energy conversion, production of liquid fuels, wastewater treatment, nitrogen fixation, and organic synthesis. This review aims to comprehensively summarize the fundamentals and to provide the guidelines for future work in the field of TiO2-based plasmonic photocatalysis comprising the above-mentioned applications. The concepts and state-of-the-art description of important parameters including the formation of Schottky junctions, hot electron generation and transfer, near field electromagnetic enhancement, plasmon resonance energy transfer, scattering, and photothermal heating effects have been covered in this review. Synthetic approaches and the effect of various physicochemical parameters in plasmon-mediated TiO2-based materials on performances are discussed. It is envisioned that this review may inspire and provide insights into the rational development of the next generation of TiO2-based plasmonic photocatalysts with target performances and enhanced selectivities.Peer reviewe

    Potential of Pandanus odoratissimus as a CNS depressant in Swiss albino mice

    Get PDF
    In this study, several neuropharmacological effects of methanolic leaf extract of Pandanus odoratissimus (PO) (family; Pandanaceae) were studied in albino mice using various experimental models. The effect of PO on the CNS was studied by using different neuropharmacological paradigms including spontaneous motor activity, rota-rod performance and potentiation of Pentobarbital sodium sleeping time in albino mice. Preliminary phytochemical evaluation and acute toxicity studies were also carried out where LD50 >;2000 mg/kg was considered non-toxic through acute exposure in rats by the oral route. The methanolic leaf extract (50,100 and 200 mg/kg i. p.) produced a reduction in spontaneous motor activity, motor coordination and prolonged Pentobarbital sodium sleeping time. Preliminary qualitative chemical studies indicated the presence of steroids, saponins, terpinoids, glycosides, tannins, flavonoids and phenolics in the extract. These observations suggest that the leaf of Pandanus odoratissimus contains some active principles which possess potential CNS-depressant actionEstudaram-se alguns efeitos neurofarmacológicos do extrato metanólico de Pandanus odoratissimus (PO) (família Pandanaceae) em camundongos albinos, usando vários modelos experimentais. O efeito do PO no SNC foi estudado por meio de diferentes paradigmas neurofarmacológicos, como atividade motora espontânea, desempenho na haste rotatória e a potenciação do tempo de sono em camundongos albinos pelo pentobarbital sódico. A avaliação fitoquímica preliminar e os estudos de toxicidade aguda foram realizados e a DL50 >;2000 mg/kg é considerada não tóxica, por meio da exposição aguda, por via oral, em ratos. O extrato metanólico de folha (50,100 e 200 mg/kg i. p.) produziu redução da atividade motora espontânea, da coordenação motora e tempo prolongado de sono pelo pentobarbital sódico. Estudos químicos qualitativos preliminares indicaram a presença de esteróide, saponinas, terpenóides, glicosídios, taninos, flavonóides e fenólicos no extrato. As observações sugerem que a folha de Pandanus odoratissimus contém alguns princípios ativos com atividade potencial como depressores do SNC
    corecore