158 research outputs found

    Estimation of the sea surface drag coefficient based on wave data

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    The sea surface drag coefficient, an important parameter for the energy transfer process in wave prediction model, is generally expressed by a linear function of wind speed. However, it seems inadequate to apply these equations for strong wind conditions because these equations were deduced from the observational or the\ud experimental data under wind speed of lower than 25m/s at fastest. To solve this problem, a wave prediction model ADWAM which includes a data assimilation method seems effective. For the purpose of clarifying the appropriate values of the sea surface drag coefficient in high wind speed, the ADWAM was modified to estimate the sea surface drag coefficients as its control variables of the model. In this study, the sea surface drag coefficient was deduced from the actual wave observation data. As a results, the sea surface drag coefficient, unknown parameter, was confirmed to\ud be modified from arbitrary initial value to an appropriate value. Also, it was confirmed that the sea surface drag coefficient under stormy condition can be estimated based on the wave data observed outside the storm if the waves propagated from the storm were observed

    Dietary ether lipid incorporation into tissue plasmalogens of humans and rodents

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    Chronic feeding of 1‐O‐octadecyl‐sn‐glycerol (batyl alcohol) to patients suffering from congenital deficiency in tissue ether glycerolipids showed an increase in the plasmalogens content of their erythrocytes. However, nothing is known about the ether lipid content of other tissues in these patients. Feeding 1‐O‐heptadecyl‐sn‐glycerol to young rats showed that this uncommon ether lipid was incorporated to a high extent into the plasmalogens of all tissues except brain. Comparative studies with other precursors, such as 3‐O‐heptadecyl‐sn‐glycerol, heptadecanol and heptadecanoic acid, indicated a stereospecific incorporation of the dietary 1‐O‐alkyl‐sn‐glycerols into tissue plasmalogens without cleavage of the ether bond. Dietary ether lipids were also shown to be transferred from mothers to suckling rats, but not from pregnant rats to fetuses. The implication of these results to possible dietary ether lipid therapy for patients suffering from peroxisomal disorders is discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141558/1/lipd0401.pd

    Oral ether lipid therapy in patients with peroxisomal disorders

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42493/1/10545_2005_Article_BF01811415.pd

    Phospholipid Scramblase 1 Potentiates The Antiviral Activity of Interferon

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    Phospholipid scramblase 1 (PLSCR1) is an interferon (IFN)- and growth factor-inducible, calcium-binding protein that either inserts into the plasma membrane or binds DNA in the nucleus depending on its state of palmyitoylation. In certain hematopoietic cells, PLSCR1 is required for normal maturation and terminal differentiation from progenitor cells as regulated by select growth factors, where it promotes recruitment and activation of Src kinases. PLSCR1 is a substrate of Src (and Abl) kinases, and transcription of the PLSCR1 gene is regulated by the same growth factor receptor pathways in which PLSCR1 potentiates afferent signaling. The marked transcriptional upregulation of PLSCR1 by IFNs led us to explore whether PLSCR1 plays an analogous role in cellular responses to IFN, with specific focus on antiviral activities. Accordingly, human cells in which PLSCR1 expression was decreased with short interfering RNA were rendered relatively insensitive to the antiviral activity of IFNs, resulting in higher titers of vesicular stomatitis virus (VSV) and encephalomyocarditis virus. Similarly, VSV replicated to higher titers in mouse PLSCR1βˆ’/βˆ’ embryonic fibroblasts than in identical cells transduced to express PLSCR1. PLSCR1 inhibited accumulation of primary VSV transcripts, similar to the effects of IFN against VSV. The antiviral effect of PLSCR1 correlated with increased expression of a subset of IFN-stimulated genes (ISGs), including ISG15, ISG54, p56, and guanylate binding proteins. Our results suggest that PLSCR1, which is itself an ISG-encoded protein, provides a mechanism for amplifying and enhancing the IFN response through increased expression of a select subset of potent antiviral genes

    Zellweger syndrome: Diagnostic assays, syndrome delineation, and potential therapy

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    Patients with the cerebrohepatorenal syndrome of Zellweger lack peroxisomes and certain peroxisomal enzymes such as dihydroxyacetone phosphate acyltransferase in their tissues. Deficiency of this enzyme, which is necessary for glycerol ether lipid synthesis, provides a biochemical method for recognizing patients with subtle manifestations of Zellweger syndrome and suggests the utility of exogenous ether lipid precursors as a therapeutic strategy for these children. We describe the results of glycerol ether lipid supplementation to two children, one with classic Zellweger syndrome and 9% of control fibroblast dihydroxyacetone phosphate acyltransferase activity, and one with mild facial manifestations, wide sutures, hypotonia, developmental delay, hepatomegaly, peripheral retinal pigmentation, and 50% of control fibroblast dihydroxyacetone phosphate acyltransferase activity. An increase in erythrocyte plasmalogen levels following therapy was clearly demonstrated in the milder patient, and neither patient showed evidence of toxicity. Evaluation of therapy by comparison to the usual clinical course of Zellweger syndrome was not helpful because of the variability and incomplete documentation of 90 previously reported cases. The literature survey did provide criteria for classic Zellweger syndrome, which include hypotonia with or without deformation of limbs, large fontanels and split sutures, prominent forehead, flattened facial profile with hypoplastic supraorbital ridges, anteverted nares, highly arched palate, cryptorchidism or labial hypoplasia, hepatomegaly or elevated liver enzymes, peripheral pigmentation of the retina, renal cortical cysts, and characteristic neuropathology involving decreased myelinization, abnormal neuronal migration, and sudanophilic macrophages. Less severe patients, as exemplified by our case 2 and others from the literature, will not have all the classic features and can be recognized only by a growing panel of biochemical indicators. Our patient studies illustrate the complexity of designing comprehensive therapy for Zellweger-like conditions, suggest other diseases that may involve peroxisomal alterations, and emphasize the need for multicenter, collaborative studies to evaluate biochemical heterogeneity and therapy of peroxisomal disorders.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38241/1/1320240109_ftp.pd

    Building Scalable Cyber-Physical-Social Networking Infrastructure Using IoT and Low Power Sensors

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    Wireless Sensors are an important component to develop the Internet of Things (IoT) Sensing infrastructure. There are enormous numbers of sensors connected with each other to form a network (well known as wireless sensor networks) to complete IoT Infrastructure. These deployed wireless sensors are with limited energy and processing capabilities. IoT infrastructure becomes a key factor to building cyber-physical-social networking infrastructure, where all these sensing devices transmit data towards the cloud data center. Data routing towards cloud data center using such low power sensor is still a challenging task. In order to prolong the lifetime of the IoT sensing infrastructure and building scalable cyber infrastructure, there is the requirement of sensing optimization and energy efficient data routing. Towards addressing these issues of IoT sensing, this paper proposes a novel rendezvous data routing protocol for low power sensors. The proposed method divides the sensing area into a number of clusters to lessen the energy consumption with data accumulation and aggregation. As a result, there will be less amount of data stream to the network. Another major reason to select cluster-based data routing is to reduce the control overhead. Finally, the simulation of the proposed method is done in the Castalia simulator to observe the performance. It has been concluded that the proposed method is energy efficient and it prolongs the networks lifetime for scalable IoT infrastructure

    Defining Global Gene Expression Changes of the Hypothalamic-Pituitary-Gonadal Axis in Female sGnRH-Antisense Transgenic Common Carp (Cyprinus carpio)

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    BACKGROUND: The hypothalamic-pituitary-gonadal (HPG) axis is critical in the development and regulation of reproduction in fish. The inhibition of neuropeptide gonadotropin-releasing hormone (GnRH) expression may diminish or severely hamper gonadal development due to it being the key regulator of the axis, and then provide a model for the comprehensive study of the expression patterns of genes with respect to the fish reproductive system. METHODOLOGY/PRINCIPAL FINDINGS: In a previous study we injected 342 fertilized eggs from the common carp (Cyprinus carpio) with a gene construct that expressed antisense sGnRH. Four years later, we found a total of 38 transgenic fish with abnormal or missing gonads. From this group we selected the 12 sterile females with abnormal ovaries in which we combined suppression subtractive hybridization (SSH) and cDNA microarray analysis to define changes in gene expression of the HPG axis in the present study. As a result, nine, 28, and 212 genes were separately identified as being differentially expressed in hypothalamus, pituitary, and ovary, of which 87 genes were novel. The number of down- and up-regulated genes was five and four (hypothalamus), 16 and 12 (pituitary), 119 and 93 (ovary), respectively. Functional analyses showed that these genes involved in several biological processes, such as biosynthesis, organogenesis, metabolism pathways, immune systems, transport links, and apoptosis. Within these categories, significant genes for neuropeptides, gonadotropins, metabolic, oogenesis and inflammatory factors were identified. CONCLUSIONS/SIGNIFICANCE: This study indicated the progressive scaling-up effect of hypothalamic sGnRH antisense on the pituitary and ovary receptors of female carp and provided comprehensive data with respect to global changes in gene expression throughout the HPG signaling pathway, contributing towards improving our understanding of the molecular mechanisms and regulative pathways in the reproductive system of teleost fish

    Different Effect of Proteasome Inhibition on Vesicular Stomatitis Virus and Poliovirus Replication

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    Proteasome activity is an important part of viral replication. In this study, we examined the effect of proteasome inhibitors on the replication of vesicular stomatitis virus (VSV) and poliovirus. We found that the proteasome inhibitors significantly suppressed VSV protein synthesis, virus accumulation, and protected infected cells from toxic effect of VSV replication. In contrast, poliovirus replication was delayed, but not diminished in the presence of the proteasome inhibitors MG132 and Bortezomib. We also found that inhibition of proteasomes stimulated stress-related processes, such as accumulation of chaperone hsp70, phosphorylation of eIF2Ξ±, and overall inhibition of translation. VSV replication was sensitive to this stress with significant decline in replication process. Poliovirus growth was less sensitive with only delay in replication. Inhibition of proteasome activity suppressed cellular and VSV protein synthesis, but did not reduce poliovirus protein synthesis. Protein kinase GCN2 supported the ability of proteasome inhibitors to attenuate general translation and to suppress VSV replication. We propose that different mechanisms of translational initiation by VSV and poliovirus determine their sensitivity to stress induced by the inhibition of proteasomes. To our knowledge, this is the first study that connects the effect of stress induced by proteasome inhibition with the efficiency of viral infection
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