302 research outputs found

    Numerical calculation of particle collection efficiency in an electrostatic precipitator

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    The present numerical study involves the finding of the collection efficiency of an electrostatic precipitator (ESP) using a finite volume (ANUPRAVAHA) solver for the Navier–Stokes and continuity equations, along with the Poisson’s equation for electric potential and current continuity. The particle movement is simulated using a Lagrangian approach to predict the trajectory of single particles in a fluid as the result of various forces acting on the particle. The ESP model consists of three wires and three collecting plates of combined length of L placed one after another. The calculations are carried out for a wire-to-plate spacing H= 0.175 m, length of ESP L= 2.210 m and wire-to-wire spacing of 0.725 m with radius of wire R wire= 10 mm and inlet air-particle velocity of 1.2 m/s. Different electrical potentials (φ= 15–30 kV) are applied to the three discharge electrodes wires. It is seen that the particle collection efficiency of the ESP increases with increasing particle diameter, electrical potential and plate length for a given inlet velocity

    Agent-based homeostatic control for green energy in the smart grid

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    With dwindling non-renewable energy reserves and the adverse effects of climate change, the development of the smart electricity grid is seen as key to solving global energy security issues and to reducing carbon emissions. In this respect, there is a growing need to integrate renewable (or green) energy sources in the grid. However, the intermittency of these energy sources requires that demand must also be made more responsive to changes in supply, and a number of smart grid technologies are being developed, such as high-capacity batteries and smart meters for the home, to enable consumers to be more responsive to conditions on the grid in real-time. Traditional solutions based on these technologies, however, tend to ignore the fact that individual consumers will behave in such a way that best satisfies their own preferences to use or store energy (as opposed to that of the supplier or the grid operator). Hence, in practice, it is unclear how these solutions will cope with large numbers of consumers using their devices in this way. Against this background, in this paper, we develop novel control mechanisms based on the use of autonomous agents to better incorporate consumer preferences in managing demand. These agents, residing on consumers' smart meters, can both communicate with the grid and optimise their owner's energy consumption to satisfy their preferences. More specifically, we provide a novel control mechanism that models and controls a system comprising of a green energy supplier operating within the grid and a number of individual homes (each possibly owning a storage device). This control mechanism is based on the concept of homeostasis whereby control signals are sent to individual components of a system, based on their continuous feedback, in order to change their state so that the system may reach a stable equilibrium. Thus, we define a new carbon-based pricing mechanism for this green energy supplier that takes advantage of carbon-intensity signals available on the internet in order to provide real-time pricing. The pricing scheme is designed in such a way that it can be readily implemented using existing communication technologies and is easily understandable by consumers. Building upon this, we develop new control signals that the supplier can use to incentivise agents to shift demand (using their storage device) to times when green energy is available. Moreover, we show how these signals can be adapted according to changes in supply and to various degrees of penetration of storage in the system. We empirically evaluate our system and show that, when all homes are equipped with storage devices, the supplier can significantly reduce its reliance on other carbon-emitting power sources to cater for its own shortfalls. By so doing, the supplier reduces the carbon emission of the system by up to 25% while the consumer reduces its costs by up to 14.5%. Finally, we demonstrate that our homeostatic control mechanism is not sensitive to small prediction errors and the supplier is incentivised to accurately predict its green production to minimise costs

    Anti-inflammatory and analgesic activity of different fractions of Boswellia serrata

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    The study was designed to investigate the anti-inflammatory and analgesic effect of different fractions of Boswellia serrata. The effect of different fractions of Boswellia serrata were studied using carrageenan induced paw edema, acetic acid induced writhing response, formalin induced pain, hot plate and tail flick method for studying anti-inflammatory and analgesic activity, respectively. The different fractions of B. serrata, essential oil (10 ml/kg), gum (100 mg/kg, resin (100 mg/kg) oleo-resin (100 mg/kg) and oleo-gum-resin (100 mg/kg) significantly reduces carrageenan induced inflammation in rats and shows analgesic activity, as determined by acetic acid induced writhing response, formalin induced pain, hot plate and tail flick method. The different fractions of B. serrata showed prompt anti-inflammatory and analgesic activity due to the inhibition of 5-lipoxygenase enzyme.Keywords: Analgesic; Boswellia serrata; Inflammation; 5- lipoxygenase; Burseraceae

    To evaluate and compare the efficacy of alcoholic and aqueous extract of Lagenaria siceraria in high fat diet model in wistar rats

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    Background: Obesity is not only affecting the affluent society but also affecting developing countries like India. The incidence of obesity is rapidly increasing throughout the world. However, the current anti-obesity drugs have numerous limitations.Methods: The obesity was induced in male wistar rats by giving high-fat diet over 12 weeks. The variables assessed were body weight, abdominal girth, blood triglyceride level, liver weight and fat mass and histopathology of liver. Aqueous and alcoholic extracts of Lagenaria siceraria (200mg/kg and 400mg/kg Doses) were compared to orlistat (treatment control) and high-fat diet group (disease control) for different variables.Results: Alcoholic and aqueous extracts high dose (400mg/kg) of Lagenaria siceraria significantly reduced total body weight (p<0.05), abdominal girth (p <0.05) at week 10 and 12 compared to high fat diet group. Alcoholic extract (400mg/kg) significantly reduced total blood triglyceride level (p <0.05) and total liver weight (p <0.05) compared to high-fat diet group. None of the study drugs reduced % liver weight. Alcoholic extract high dose (p <0.05) has shown improvement in histopathological score. Both aqueous and alcoholic extracts have shown reduced fat mass compared to high-fat diet group.Conclusions: The alcoholic extract (400mg/kg) of Lagenaria siceraria alleviated high fat diet induced obesity and dyslipidemic changes in rats. The alcoholic extract of Lagenaria siceraria is having better anti-obesity potential than aqueous extract

    Paramagnetic GaN:Fe and ferromagnetic (Ga,Fe)N - relation between structural, electronic, and magnetic properties

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    We report on the metalorganic chemical vapor deposition (MOCVD) of GaN:Fe and (Ga,Fe)N layers on c-sapphire substrates and their thorough characterization via high-resolution x-ray diffraction (HRXRD), transmission electron microscopy (TEM), spatially-resolved energy dispersive X-ray spectroscopy (EDS), secondary-ion mass spectroscopy (SIMS), photoluminescence (PL), Hall-effect, electron-paramagnetic resonance (EPR), and magnetometry employing a superconducting quantum interference device (SQUID). A combination of TEM and EDS reveals the presence of coherent nanocrystals presumably FexN with the composition and lattice parameter imposed by the host. From both TEM and SIMS studies, it is stated that the density of nanocrystals and, thus the Fe concentration increases towards the surface. In layers with iron content x<0.4% the presence of ferromagnetic signatures, such as magnetization hysteresis and spontaneous magnetization, have been detected. We link the presence of ferromagnetic signatures to the formation of Fe-rich nanocrystals, as evidenced by TEM and EDS studies. This interpretation is supported by magnetization measurements after cooling in- and without an external magnetic field, pointing to superparamagnetic properties of the system. It is argued that the high temperature ferromagnetic response due to spinodal decomposition into regions with small and large concentration of the magnetic component is a generic property of diluted magnetic semiconductors and diluted magnetic oxides showing high apparent Curie temperature.Comment: 21 pages, 30 figures, submitted to Phys. Rev.

    Reversal of cell, circuit and seizure phenotypes in a mouse model of DNM1epileptic encephalopathy

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    Dynamin-1 is a large GTPase with an obligatory role in synaptic vesicle endocytosis at mammalian nerve terminals. Heterozygous missense mutations in the dynamin-1 gene (DNM1) cause a novel form of epileptic encephalopathy, with pathogenic mutations clustering within regions required for its essential GTPase activity. We reveal the most prevalent pathogenic DNM1 mutation, R237W, disrupts dynamin-1 enzyme activity and endocytosis when overexpressed in central neurons. To determine how this mutation impacted cell, circuit and behavioural function, we generated a mouse carrying the R237W mutation. Neurons from heterozygous mice display dysfunctional endocytosis, in addition to altered excitatory neurotransmission and seizure-like phenotypes. Importantly, these phenotypes are corrected at the cell, circuit and in vivo level by the drug, BMS-204352, which accelerates endocytosis. Here, we demonstrate a credible link between dysfunctional endocytosis and epileptic encephalopathy, and importantly reveal that synaptic vesicle recycling may be a viable therapeutic target for monogenic intractable epilepsies.<br/

    Present status and future prospects of Gir cow

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    Gir cattle in Saurashtra provide milk, manure and draught power. Animal genetic resources of native breeds are largely underutilized in India and indiscriminate crossbreeding has degraded large numbers of local breeds. This is also true with Gir cattle in its native breeding tract. (i) About two-third population is either graded Gir or Gir like and hence not pure Gir, (ii) only one-third population i.e. 7.6 lakh could be 95% towards pure Gir. Hence, it is difficult to obtain large number of pure Gir animals. Since 2003–04 to 2012– 13, contribution of Saurashtra to state total indigenous cattle milk yield is 60%. A 25 years data analysis on Gir cows at CBF revealed average lactation yield as 2029 litre in 321 days lactation length and 1843.8 litre milk yield in 300 days. Production performance of Gir cows in three districts:(1) Junagadh (2) Rajkot and (3) Bhavnagar showed that average test day milk yield in Gir cows over a lactation were 7.99±0.05 litre/d for Junagadh, 6.43±0.03 litre/d for Rajkot and 6.71±0.04 litre /d for Bhavnagar district, projected values for 300-days milk yield being was 2397, 1929, and 2013 litre for the three districts respectively. Average AFC in Gir cattle of the station herd was 1527.7±14.1 days (51 mth) whereas survey study in Junagadh, Rajkot and Bhavnagar districts indicated AFC in field Gir cows as 45, 49, and 46 month, respectively. Parity had a significant effect on total lactation milk yield in Gir cows at CBF. Highest total lactation yield was observed in 2nd lactation (2132±123.4 litre) while lowest was observed in 10th lactation (1456.8±219.1 litre). Milk production traits LY and 300-d LY exhibited 10 to 13 % genetic variability in the herd. This suggests that to increase variability in the herd, genetic material from outside herd needs to be introduced

    Knowledge distillation for quality estimation

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    Quality Estimation (QE) is the task of automatically predicting Machine Translation quality in the absence of reference translations, making it applicable in real-time settings, such as translating online social media conversations. Recent success in QE stems from the use of multilingual pre-trained representations, where very large models lead to impressive results. However, the inference time, disk and memory requirements of such models do not allow for wide usage in the real world. Models trained on distilled pre-trained representations remain prohibitively large for many usage scenarios. We instead propose to directly transfer knowledge from a strong QE teacher model to a much smaller model with a different, shallower architecture. We show that this approach, in combination with data augmentation, leads to light-weight QE models that perform competitively with distilled pre-trained representations with 8x fewer parameters

    Surfactant protein D inhibits HIV-1 infection of target cells via interference with gp120-CD4 interaction and modulates pro-inflammatory cytokine production

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    © 2014 Pandit et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Surfactant Protein SP-D, a member of the collectin family, is a pattern recognition protein, secreted by mucosal epithelial cells and has an important role in innate immunity against various pathogens. In this study, we confirm that native human SP-D and a recombinant fragment of human SP-D (rhSP-D) bind to gp120 of HIV-1 and significantly inhibit viral replication in vitro in a calcium and dose-dependent manner. We show, for the first time, that SP-D and rhSP-D act as potent inhibitors of HIV-1 entry in to target cells and block the interaction between CD4 and gp120 in a dose-dependent manner. The rhSP-D-mediated inhibition of viral replication was examined using three clinical isolates of HIV-1 and three target cells: Jurkat T cells, U937 monocytic cells and PBMCs. HIV-1 induced cytokine storm in the three target cells was significantly suppressed by rhSP-D. Phosphorylation of key kinases p38, Erk1/2 and AKT, which contribute to HIV-1 induced immune activation, was significantly reduced in vitro in the presence of rhSP-D. Notably, anti-HIV-1 activity of rhSP-D was retained in the presence of biological fluids such as cervico-vaginal lavage and seminal plasma. Our study illustrates the multi-faceted role of human SPD against HIV-1 and potential of rhSP-D for immunotherapy to inhibit viral entry and immune activation in acute HIV infection. © 2014 Pandit et al.The work (Project no. 2011-16850) was supported by Medical Innovation Fund of Indian Council of Medical Research, New Delhi, India (www.icmr.nic.in/)
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