1,008 research outputs found

    Thermal Analysis of Vertical Heated Cylindrical Surface Employing V - Shape Fin Surfaces

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    Natural convection is an important and economical mode of heat transfer .It is used in many of the engineering applications such as cooling of electronic components, cooling of Printed circuit boards, HVAC & R, I.C. engines fins, radiators of automobiles etc. Some of these heat sinks are cylindrical in shape. The heat that is produced in such system that conducts through the walls surfaces is need to be continuously dissipated to the surrounding atmosphere to keep the system in steady state condition. More quantities of heat have to be dissipated from small area as heat transfer by convection between a surface and the fluid surroundings. It can be improved by attaching fins or by use of some form of extended surfaces. V shape fin geometries have been selected for cooling such cylindrical surfaces or heat sinks. Initially the dimensions for the vertical cylinder with array of v shape fins have been obtained. Computational analysis of array of v shape fins over vertical heated cylinder have been studied by using Ansys software. The results reveal that the 60-degree V-shaped fins exhibit the highest natural convection heat transfer coefficient, owing to their streamlined flow-promoting characteristics. These V-shaped fins act as flow turbulators, causing minimal air obstruction and, consequently, enhancing heat dissipation. The computational findings are further validated by comparing them with analytical results, affirming the effectiveness of this approach in improving heat transfer from cylindrical surfaces. This research contributes to the understanding and optimization of natural convection heat transfer in cylindrical systems utilizing V-shaped fins, demonstrating its potential for enhancing thermal performance in various engineering application

    Self-generated magnetic flux in YBa2_2Cu3_3O7−x_{7-x} grain boundaries

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    Grain boundaries in YBa2_2Cu3_3O7−x_{7-x} superconducting films are considered as Josephson junctions with a critical current density jc(x)j_c(x) alternating along the junction. A self-generated magnetic flux is treated both analytically and numerically for an almost periodic distribution of jc(x)j_c(x). We obtained a magnetic flux-pattern similar to the one which was recently observed experimentally.Comment: 7 pages, 3 figure

    Standardization of organic manure application in pomegranate (Punica granatum) orchards grown in semi-arid regions

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    An experiment was conducted at ICAR - National Research Centre on Pomegranate during 2011-12 and 2012-13 on pomegranate (Punica granatum L) cv. Bhagwa plants. The experiment comprises of application of raw and well decomposed farmyard manure in the form of slurry (liquid form, manures mixed with water in 1:10 ratio and kept for 10 to 15 days with intermittent stirring) as a sole or in combination with micronutrients and/or various microbial inoculants. It was compared with normally practiced method of organic manure application in the soil. The results revealed that application of farmyard manure in slurry form decreased electrical conductivity (0.94 to 0.72 dS/m) and increased organic carbon content (0.55 to 1.45 %) in the soil. Combined application of FYM in the form of slurry along with micronutrients and microbial inoculants significantly increased available N (339.7 kg/ha) and P (34.8 kg/ha) and micronutrients content in the soil. Substantially increased plant height (20.8%), plant spread (22.8 %) and produced maximum number of fruits (39.0/ plant). Population of soil microbes, viz. Aspergillus niger, Pseudomonas fluorescence and potash solubilising organisms were significantly highest with the combined application of FYM in slurry form and microbial inoculants. While, Azotobacter population was more in raw FYM slurry along with microbial inoculants. It is recommended that on light textured soils, farmyard manures should be applied in the form of slurry. It reaches in the active root zone of the plants along with percolating water

    Functional characterization of enhancer activity during a long terminal repeat\u27s evolution

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    Many transposable elements (TEs) contain transcription factor binding sites and are implicated as potential regulatory elements. However, TEs are rarely functionally tested for regulatory activity, which in turn limits our understanding of how TE regulatory activity has evolved. We systematically tested the human LTR18A subfamily for regulatory activity using massively parallel reporter assay (MPRA) and found AP-1- and CEBP-related binding motifs as drivers of enhancer activity. Functional analysis of evolutionarily reconstructed ancestral sequences revealed that LTR18A elements have generally lost regulatory activity over time through sequence changes, with the largest effects occurring owing to mutations in the AP-1 and CEBP motifs. We observed that the two motifs are conserved at higher rates than expected based on neutral evolution. Finally, we identified LTR18A elements as potential enhancers in the human genome, primarily in epithelial cells. Together, our results provide a model for the origin, evolution, and co-option of TE-derived regulatory elements

    Throughput analysis of full-duplex communication cognitive radio network

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    In this paper we deal with the throughput of full-duplex cognitive communication radio which exploits unused band of primary user (PU) network. Classical cognitive radio uses half-duplex communication spectrum sensing to perform spectrum sensing and data transmission at different time intervals. It’s well-established fact that in half-duplex communication cognitive radio spectrum sensing time increases at low SNR which gives rise to lesser data transmission time for secondary user (SU) and hence results in less throughput for SU. It’s useful idea to do spectrum sensing and data transmission at the same time with two different antennas co-located on the SU transceiver. This shall not only guarantee high probability of detection of PU but also increased data transmission which means more throughput for SU. However, simultaneous sensing and data transmission has inherent problem of self-interference. One of the possible solution is to use polarisation discrimination in which sensing and data transmission antennas must use different polarisation. This is feasible if there is prior information about the polarisation of the signals emitted by the PUs. It shall be of special interest to assess throughput using analytical expressions for probability of detection PD, probability of false alarm PFA at various values of SNR for time-slotted cognitive radio which uses half-duplex spectrum sensing and non-time-slotted cognitive radio which uses full-duplex communication cognitive radio

    Artificial Intelligence and Endo-Histo-OMICs: New Dimensions of Precision Endoscopy and Histology in Inflammatory Bowel Disease

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    Integrating artificial intelligence into inflammatory bowel disease (IBD) has the potential to revolutionise clinical practice and research. Artificial intelligence harnesses advanced algorithms to deliver accurate assessments of IBD endoscopy and histology, offering precise evaluations of disease activity, standardised scoring, and outcome prediction. Furthermore, artificial intelligence offers the potential for a holistic endo-histo-omics approach by interlacing and harmonising endoscopy, histology, and omics data towards precision medicine. The emerging applications of artificial intelligence could pave the way for personalised medicine in IBD, offering patient stratification for the most beneficial therapy with minimal risk. Although artificial intelligence holds promise, challenges remain, including data quality, standardisation, reproducibility, scarcity of randomised controlled trials, clinical implementation, ethical concerns, legal liability, and regulatory issues. The development of standardised guidelines and interdisciplinary collaboration, including policy makers and regulatory agencies, is crucial for addressing these challenges and advancing artificial intelligence in IBD clinical practice and trials

    Twin boundaries in d-wave superconductors

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    Twin boundaries in orthorhombic d-wave superconductors are investigated numerically using the Bogoliubov-deGennes formalism within the context of an extended Hubbard model. The twin boundaries are represented by tetragonal regions of variable width, with a reduced chemical potential. For sufficiently large twin boundary width and change in chemical potential, an induced s-wave component may break time-reversal symmetry at a low temperature. This temperature, and the magnitude of the complex component, are found to depend strongly on electron density. The results are compared with recent tunneling measurements.Comment: ReVTeX, 4 pages, 4 postscript figure

    Josephson tunneling in high-TcT_c superconductors

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    This article describes the Josephson tunneling from time-reversal symmetry-breaking states and compares it with that from time-reversal invariant states for both twinned and untwinned crystals and for both cc-axis and basal-plane currents, in a model for orthorhombic YBCO. A macroscopic invariance group describing the superconducting state of a twinned crystal is introduced and shown to provide a useful framework for the discussion of the results for twinned crystals. In addition, a ring geometry, which allows ss-wave and dx2−y2d_{x^2-y^2}-wave superconductivity in a tetragonal superconductor to be distinguished on the basis of symmetry arguments only, is proposed and analyzed. Finally, an appendix gives details of the experimental Josephson tunneling evidence for a superconducting state of orthorhombic ux2+vy2ux^2+vy^2 symmetry in YBCO.Comment: Latex File, 18 pages, 6 Postscript figures, submitted to Phys. Rev.

    On the selection and design of proteins and peptide derivatives for the production of photoluminescent, red-emitting gold quantum clusters

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    Novel pathways of the synthesis of photoluminescent gold quantum clusters (AuQCs) using biomolecules as reactants provide biocompatible products for biological imaging techniques. In order to rationalize the rules for the preparation of red-emitting AuQCs in aqueous phase using proteins or peptides, the role of different organic structural units was investigated. Three systems were studied: proteins, peptides, and amino acid mixtures, respectively. We have found that cysteine and tyrosine are indispensable residues. The SH/S-S ratio in a single molecule is not a critical factor in the synthesis, but on the other hand, the stoichiometry of cysteine residues and the gold precursor is crucial. These observations indicate the importance of proper chemical behavior of all species in a wide size range extending from the atomic distances (in the AuI-S semi ring) to nanometer distances covering the larger sizes of proteins assuring the hierarchical structure of the whole self-assembled system
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