225 research outputs found

    Application of Numerical Newton-Raphson Method in Calculation of Emitter Water Discharge of Drip Irrigation System in “Mutis Cemerlang” Coffee Plantation

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    Based on the slope class, the shape of the area and the elevation of dry land in Nusa Tenggara, agricultural land in Noepesu Village is suitable for planting coffee plants with an agroforestry scheme. To overcome the problem of limited water, drip irrigation system technology can be applied. The use of drip irrigation as an agricultural technology in Noepesu village has been carried out by many farmer groups. Still, the installation process does not consider the pipe specifications (pipe length and pipe diameter) and the condition of agricultural land. This causes the service life of drip irrigation to be not long. If this continues, of course, it will increase system installation costs. To optimize service life, a hydraulics analysis method is needed for drip irrigation pipe network systems that take into account pipe specifications and agricultural land conditions.The hydraulics analysis of the drip irrigation network system determines the emitter’s water flow rate. The emitter flow rate forms a nonlinear equation known as the closed pipe equation. In the process of solving these equations, numerical methods can be used, specifically the Newton-Raphson method. This study focuses on applying the Newton-Raphson method to calculate the amount of water discharge from each emitter of the drip irrigation network system on the farmland of the Mutis Cemerlang Farmer Group in Noepesu Village. The drip irrigation system is designed with 250 nodes, 275 pipes, 26 loops, and 86 outlets divided into two sides, with the left side containing 84 outlets with one emitter and the right side containing 102 outlets with two emitters. The amount of water discharge for each emitter is 0,0008 ml/second≤Q≤2,6 ml/second for the left side and 0,001 ml/second≤Q≤1,1 ml/second for the right side, as determined by simulation calculations utilizing the Newton-Raphson method and Matlab software. The simulation results show that the amount of water discharge at each emitter is ideal in the first iteration because it has a discharge correction value (∆Q)≈0

    Human Sclera Maintains Common Characteristics with Cartilage throughout Evolution

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    BACKGROUND: The sclera maintains and protects the eye ball, which receives visual inputs. Although the sclera does not contribute significantly to visual perception, scleral diseases such as refractory scleritis, scleral perforation and pathological myopia are considered incurable or difficult to cure. The aim of this study is to identify characteristics of the human sclera as one of the connective tissues derived from the neural crest and mesoderm. METHODOLOGY/PRINCIPAL FINDINGS: We have demonstrated microarray data of cultured human infant scleral cells. Hierarchical clustering was performed to group scleral cells and other mesenchymal cells into subcategories. Hierarchical clustering analysis showed similarity between scleral cells and auricular cartilage-derived cells. Cultured micromasses of scleral cells exposed to TGF-betas and BMP2 produced an abundant matrix. The expression of cartilage-associated genes, such as Indian hedge hog, type X collagen, and MMP13, was up-regulated within 3 weeks in vitro. These results suggest that human 'sclera'-derived cells can be considered chondrocytes when cultured ex vivo. CONCLUSIONS/SIGNIFICANCE: Our present study shows a chondrogenic potential of human sclera. Interestingly, the sclera of certain vertebrates, such as birds and fish, is composed of hyaline cartilage. Although the human sclera is not a cartilaginous tissue, the human sclera maintains chondrogenic potential throughout evolution. In addition, our findings directly explain an enigma that the sclera and the joint cartilage are common targets of inflammatory cells in rheumatic arthritis. The present global gene expression database will contribute to the clarification of the pathogenesis of developmental diseases such as high myopia

    Curvature fluctuations and Lyapunov exponent at Melting

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    We calculate the maximal Lyapunov exponent in constant-energy molecular dynamics simulations at the melting transition for finite clusters of 6 to 13 particles (model rare-gas and metallic systems) as well as for bulk rare-gas solid. For clusters, the Lyapunov exponent generally varies linearly with the total energy, but the slope changes sharply at the melting transition. In the bulk system, melting corresponds to a jump in the Lyapunov exponent, and this corresponds to a singularity in the variance of the curvature of the potential energy surface. In these systems there are two mechanisms of chaos -- local instability and parametric instability. We calculate the contribution of the parametric instability towards the chaoticity of these systems using a recently proposed formalism. The contribution of parametric instability is a continuous function of energy in small clusters but not in the bulk where the melting corresponds to a decrease in this quantity. This implies that the melting in small clusters does not lead to enhanced local instability.Comment: Revtex with 7 PS figures. To appear in Phys Rev

    Big-Data-Driven Materials Science and its FAIR Data Infrastructure

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    This chapter addresses the forth paradigm of materials research -- big-data driven materials science. Its concepts and state-of-the-art are described, and its challenges and chances are discussed. For furthering the field, Open Data and an all-embracing sharing, an efficient data infrastructure, and the rich ecosystem of computer codes used in the community are of critical importance. For shaping this forth paradigm and contributing to the development or discovery of improved and novel materials, data must be what is now called FAIR -- Findable, Accessible, Interoperable and Re-purposable/Re-usable. This sets the stage for advances of methods from artificial intelligence that operate on large data sets to find trends and patterns that cannot be obtained from individual calculations and not even directly from high-throughput studies. Recent progress is reviewed and demonstrated, and the chapter is concluded by a forward-looking perspective, addressing important not yet solved challenges.Comment: submitted to the Handbook of Materials Modeling (eds. S. Yip and W. Andreoni), Springer 2018/201

    Defining Developmental Potency and Cell Lineage Trajectories by Expression Profiling of Differentiating Mouse Embryonic Stem Cells

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    Biologists rely on morphology, function and specific markers to define the differentiation status of cells. Transcript profiling has expanded the repertoire of these markers by providing the snapshot of cellular status that reflects the activity of all genes. However, such data have been used only to assess relative similarities and differences of these cells. Here we show that principal component analysis of global gene expression profiles map cells in multidimensional transcript profile space and the positions of differentiating cells progress in a stepwise manner along trajectories starting from undifferentiated embryonic stem (ES) cells located in the apex. We present three ‘cell lineage trajectories’, which represent the differentiation of ES cells into the first three lineages in mammalian development: primitive endoderm, trophoblast and primitive ectoderm/neural ectoderm. The positions of the cells along these trajectories seem to reflect the developmental potency of cells and can be used as a scale for the potential of cells. Indeed, we show that embryonic germ cells and induced pluripotent cells are mapped near the origin of the trajectories, whereas mouse embryo fibroblast and fibroblast cell lines are mapped near the far end of the trajectories. We suggest that this method can be used as the non-operational semi-quantitative definition of cell differentiation status and developmental potency. Furthermore, the global expression profiles of cell lineages provide a framework for the future study of in vitro and in vivo cell differentiation

    No hypoperfusion is produced in the epicardium during application of myocardial topical negative pressure in a porcine model

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    ABSTRACT: BACKGROUND: Topical negative pressure (TNP), commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in skeletal muscle. We have previously shown that a myocardial TNP of -50 mmHg significantly increases microvascular blood flow in the myocardium. When TPN is used in wound therapy (on skeletal and subcutaneous tissue) a zone of relative hypoperfusion is seen close to the wound edge. Hypoperfusion induced by TNP is thought to depend on tissue density, distance from the negative pressure source, and the amount negative pressure applied. When applying TNP to the myocardium, a significant, long-standing zone of hypoperfusion could theoretically cause ischemia, and negative effects on the myocardium. The current study was designed to elucidate whether hypoperfusion was produced during myocardial TNP. METHODS: Six pigs underwent median sternotomy. Laser Doppler probes were inserted horizontally into the heart muscle in the LAD area, at depths of approximately, 1-2 mm. The microvascular blood flow was measured before and after the application of a TNP. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium) and after 20 minutes of LAD occlusion (ischemic myocardium). RESULTS: A TNP of -50 mmHg induced a significant increase in microvascular blood flow in normal myocardium (**p = 0.01), while -125 mmHg did not significantly alter the microvascular blood flow. In ischemic myocardium a TNP of -50 mmHg induced a significant increase in microvascular blood flow (*p = 0.04), while -125 mmHg did not significantly alter the microvascular blood flow. CONCLUSION: No hypoperfusion could be observed in the epicardium in neither normal nor ischemic myocardium during myocardial TNP

    A compare between myocardial topical negative pressure levels of -25 mmHg and -50 mmHg in a porcine model

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    <p>Abstract</p> <p>Background</p> <p>Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blood flow in the underlying tissue. We have also shown that a myocardial TNP levels between -75 mmHg and -150 mmHg do not induce microvascular blood flow changes in the underlying myocardium. The present study was designed to elucidate the difference between -25 mmHg and -50 mmHg TNP on microvascular flow in normal and ischemic myocardium.</p> <p>Methods</p> <p>Six pigs underwent median sternotomy. The microvascular blood flow in the myocardium was recorded before and after the application of TNP using laser Doppler flowmetry. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium), and after 20 minutes of LAD occlusion (ischemic myocardium).</p> <p>Results</p> <p>A TNP of -25 mmHg significantly increased microvascular blood flow in both normal (from 263.3 ± 62.8 PU before, to 380.0 ± 80.6 PU after TNP application, * <it>p </it>= 0.03) and ischemic myocardium (from 58.8 ± 17.7 PU before, to 85.8 ± 20.9 PU after TNP application, * <it>p </it>= 0.04). A TNP of -50 mmHg also significantly increased microvascular blood flow in both normal (from 174.2 ± 20.8 PU before, to 240.0 ± 34.4 PU after TNP application, * <it>p </it>= 0.02) and ischemic myocardium (from 44.5 ± 14.0 PU before, to 106.2 ± 26.6 PU after TNP application, ** <it>p </it>= 0.01).</p> <p>Conclusion</p> <p>Topical negative pressure of -25 mmHg and -50 mmHg both induced a significant increase in microvascular blood flow in normal and in ischemic myocardium. The increase in microvascular blood flow was larger when using -25 mmHg on normal myocardium, and was larger when using -50 mmHg on ischemic myocardium; however these differences were not statistically significant.</p

    Reactions to Brexit in images : a multimodal content analysis of shared visual content on Flickr

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    In this article, the authors analyze citizens’ reactions to Brexit on social media after the referendum results by performing a content analysis of 5877 posts collected from the social media platform Flickr, written in English, German, French, Spanish or Italian. Their research aims to answer the three following questions: What multimodal practices are adopted by citizens when they react to societal events like Brexit? To what extent do these practices illustrate types of citizenship that are specific to social networks? Can we observe different reactions to Brexit according to the languages used by the citizens? The authors focus on the types of visual content the citizens used to react to Brexit, as well as on what types of social relations this content can particularly create between their authors and the other members of the Flick community. Their article also highlights to what extent these posts shared on Flickr show content that is in favour of, or against, Brexit

    Heritability in the Efficiency of Nonsense-Mediated mRNA Decay in Humans

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    BACKGROUND: In eukaryotes mRNA transcripts of protein-coding genes in which an intron has been retained in the coding region normally result in premature stop codons and are therefore degraded through the nonsense-mediated mRNA decay (NMD) pathway. There is evidence in the form of selective pressure for in-frame stop codons in introns and a depletion of length three introns that this is an important and conserved quality-control mechanism. Yet recent reports have revealed that the efficiency of NMD varies across tissues and between individuals, with important clinical consequences. PRINCIPAL FINDINGS: Using previously published Affymetrix exon microarray data from cell lines genotyped as part of the International HapMap project, we investigated whether there are heritable, inter-individual differences in the abundance of intron-containing transcripts, potentially reflecting differences in the efficiency of NMD. We identified intronic probesets using EST data and report evidence of heritability in the extent of intron expression in 56 HapMap trios. We also used a genome-wide association approach to identify genetic markers associated with intron expression. Among the top candidates was a SNP in the DCP1A gene, which forms part of the decapping complex, involved in NMD. CONCLUSIONS: While we caution that some of the apparent inter-individual difference in intron expression may be attributable to different handling or treatments of cell lines, we hypothesize that there is significant polymorphism in the process of NMD, resulting in heritable differences in the abundance of intronic mRNA. Part of this phenotype is likely to be due to a polymorphism in a decapping enzyme on human chromosome 3

    MAP4 Mechanism that Stabilizes Mitochondrial Permeability Transition in Hypoxia: Microtubule Enhancement and DYNLT1 Interaction with VDAC1

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    Mitochondrial membrane permeability has received considerable attention recently because of its key role in apoptosis and necrosis induced by physiological events such as hypoxia. The manner in which mitochondria interact with other molecules to regulate mitochondrial permeability and cell destiny remains elusive. Previously we verified that hypoxia-induced phosphorylation of microtubule-associated protein 4 (MAP4) could lead to microtubules (MTs) disruption. In this study, we established the hypoxic (1% O2) cell models of rat cardiomyocytes, H9c2 and HeLa cells to further test MAP4 function. We demonstrated that increase in the pool of MAP4 could promote the stabilization of MT networks by increasing the synthesis and polymerization of tubulin in hypoxia. Results showed MAP4 overexpression could enhance cell viability and ATP content under hypoxic conditions. Subsequently we employed a yeast two-hybrid system to tag a protein interacting with mitochondria, dynein light chain Tctex-type 1 (DYNLT1), by hVDAC1 bait. We confirmed that DYNLT1 had protein-protein interactions with voltage-dependent anion channel 1 (VDAC1) using co-immunoprecipitation; and immunofluorescence technique showed that DYNLT1 was closely associated with MTs and VDAC1. Furthermore, DYNLT1 interactions with MAP4 were explored using a knockdown technique. We thus propose two possible mechanisms triggered by MAP4: (1) stabilization of MT networks, (2) DYNLT1 modulation, which is connected with VDAC1, and inhibition of hypoxia-induced mitochondrial permeabilization
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