430 research outputs found

    Optimum Remedial Operation of Permanent Magnet Synchronous Motor

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    In critical systems, the reliability of the drive is very important. The faults are unwanted. The faults may be lead to loss of the human life and capital. This paper is addressed this problem and suggested two models to solve it. The first model doesn’t contain any special tools to improve the torque ripple and THD. The second model contains 2PI current controllers to improvement the performance at fault and remedial operation. One is for the torque and the other is for the flux. The first PI controller is feeding from the torque error between the reference and estimated torques to get new q-axis current component representing modifier current arises from uncertain things inside the machine and drive system such as temperature and parameters variations. This current will add to reference q-axis current to get robust new q-axis current to satisfy the drive requirement and solve the torque problem (ripple torque). With robust current, the total harmonic distortion is a decrease but doesn’t reach the best value so the other PI controller is used to adjust the THD. In this PI controller, the d-axis flux is compared to rotor permanent magnet flux to solve this problem arises from non-sinusoidal of the magnetic flux. The output of the PI controller is introduced to the reference d-axis current. The new d-axis current will reach the best value of THD. The simulation of the second controller is compared to the simulation of first controller to show if the second controller strong or weak. Matlab simulink is used to simulate the drive system.DOI:http://dx.doi.org/10.11591/ijece.v2i5.72

    SAPONINS, GLYCOSIDES AND FLAVONOIDS IN CELLS AND TISSUES OF BALANITES AEGYPTIACA CULTURED ON SOLID AND LIQUID CULTURE MEDIA

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    Objectives: The main objective of the present study is to obtain callus and cell suspension culture from Balanitesa egyptiaca sterile plantlets grown in vitro and to compare growth and the biosynthetic potential of saponins, flavonoids and glycosides by callus and cell suspension culture Balanitisa egyptiaca. Methods: Callus was induced from the mother plants on MS culture media supplemented with  2.0 mg/l  BA + 2.0 mg/l  2,4-D with and without agar gelling. Total saponins, glycosides and flavonoids were estimated in both types of cultures over a period extending from 1 to 5 weeks to compare the productivity of such secondary metabolites in callus and cell suspension cultures. Results: The results obtained indicated that both calli and cell suspension cultures were able to synthesize the target active ingredients and that cell suspension culture was superior to the callus culture in the biosynthesis and accumulation processes. By the end of the incubation period, the amount of total saponins in cell suspension culture reached up 51.97±0.26 dry biomass compared to 35.02 ±0.06 mg/g in callus culture. The amount of total flavonoids in cell suspension culture reached up 10.88±0.24 dry biomass compared to 6.40±0.02 mg/g in callus culture and of total glycosides reached up 6.11±0.25 dry biomass compared to 5.06 ±0.05 mg/g in callus culture. Conclusions: The results obtained in this study may indicate the promising role that plant cell culture will play in the future in phytopharmaceutical industry.                          Peer Review History: Received 16 July 2020; Revised 12 August; Accepted 26 August, Available online 15 September 2020 Academic Editor: Dr. Iman Muhammad Higazy, National Research Center, Egypt, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency.  Received file:                Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.5/10 Reviewer(s) detail: Dr. Gehan Fawzy Abdel Raoof Kandeel, Researcher at pharmacognosy Department, National Research Centre, Egypt, [email protected] Ahmad Najib, Department of Pharmacognosy-Phytochemystry Universitas Muslim Indonesia-Indonesia, [email protected] Similar Articles: PHYTOCHEMICAL ANALYSIS AND ANTIMICROBIAL ACTIVITY OF COLOCASIA ESCULENTA (TARO) MEDICINAL PLANT LEAVES USED IN FOLK MEDICINE FOR TREATMENT OF WOUNDS AND BURNS IN HUFASH DISTRICT AL MAHWEET GOVERNORATE–YEMEN PHYTOCHEMICAL SCREENING AND THIN LAYER CHROMATOGRAPHIC OF PRUNUS DULCIS (ALMOND) MEDICINAL PLANT LEAVES USED IN FOLK MEDICINE FOR TREATMENT OF WOUNDS AND BURNS IN HUFASH DISTRICT AL MAHWEET GOVERNORATE–YEME

    Exploiting the Synergy Between Gossiping and Structured Overlays

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    In this position paper we argue for exploiting the synergy between gossip-based algorithms and structured overlay networks (SON). These two strands of research have both aimed at building fault-tolerant, dynamic, self-managing, and large-scale distributed systems. Despite the common goals, the two areas have, however, been relatively isolated. We focus on three problem domains where there is an untapped potential of using gossiping combined with SONs. We argue for applying gossip-based membership for ring-based SONs---such as Chord and Bamboo---to make them handle partition mergers and loopy networks. We argue that small world SONs---such as Accordion and Mercury---are specifically well-suited for gossip-based membership management. The benefits would be better graph-theoretic properties. Finally, we argue that gossip-based algorithms could use the overlay constructed by SONs. For example, many unreliable broadcast algorithms for SONs could be augmented with anti-entropy protocols. Similarly, gossip-based aggregation could be used in SONs for network size estimation and load-balancing purposes

    Evaluation of energy dissipation in flexure for two stage concrete

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    Concrete is a multiphase material and the energy dissipation in concrete is considered as the index to measure the capability of its ingredients to resist cyclic loading during its service life. This paper presents the results from an investigation conducted on the behaviour of two stage concrete (TSC) subjected to constant and gradual cyclic loading. A total of 128 samples were cast and tested at 28 days of normal curing, using mixes having water/cement ratio (w/c) of 0.55, 0.65, 0.75 and 0.80 and sand/cement ratio (s/c) of 1, 1.25, 1.5 and 2.0. Empirical approach namely ratio of energy dissipation (Rn) has been used to assess the results. In general, the results are comparable either in constant or gradual cyclic loading system regardless of the variation in w/c and s/c. It seems, however, that the rate of energy dissipation was slightly higher in the samples subjected to gradual cyclic loading

    Literature-based discovery of diabetes- and ROS-related targets

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    Abstract Background Reactive oxygen species (ROS) are known mediators of cellular damage in multiple diseases including diabetic complications. Despite its importance, no comprehensive database is currently available for the genes associated with ROS. Methods We present ROS- and diabetes-related targets (genes/proteins) collected from the biomedical literature through a text mining technology. A web-based literature mining tool, SciMiner, was applied to 1,154 biomedical papers indexed with diabetes and ROS by PubMed to identify relevant targets. Over-represented targets in the ROS-diabetes literature were obtained through comparisons against randomly selected literature. The expression levels of nine genes, selected from the top ranked ROS-diabetes set, were measured in the dorsal root ganglia (DRG) of diabetic and non-diabetic DBA/2J mice in order to evaluate the biological relevance of literature-derived targets in the pathogenesis of diabetic neuropathy. Results SciMiner identified 1,026 ROS- and diabetes-related targets from the 1,154 biomedical papers (http://jdrf.neurology.med.umich.edu/ROSDiabetes/). Fifty-three targets were significantly over-represented in the ROS-diabetes literature compared to randomly selected literature. These over-represented targets included well-known members of the oxidative stress response including catalase, the NADPH oxidase family, and the superoxide dismutase family of proteins. Eight of the nine selected genes exhibited significant differential expression between diabetic and non-diabetic mice. For six genes, the direction of expression change in diabetes paralleled enhanced oxidative stress in the DRG. Conclusions Literature mining compiled ROS-diabetes related targets from the biomedical literature and led us to evaluate the biological relevance of selected targets in the pathogenesis of diabetic neuropathy.http://deepblue.lib.umich.edu/bitstream/2027.42/78315/1/1755-8794-3-49.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/2/1755-8794-3-49-S7.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/3/1755-8794-3-49-S10.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/4/1755-8794-3-49-S8.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/5/1755-8794-3-49-S3.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/6/1755-8794-3-49-S1.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/7/1755-8794-3-49-S4.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/8/1755-8794-3-49-S2.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/9/1755-8794-3-49-S12.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/10/1755-8794-3-49-S11.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/11/1755-8794-3-49-S9.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/12/1755-8794-3-49-S5.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/13/1755-8794-3-49-S6.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/14/1755-8794-3-49.pdfPeer Reviewe

    Screening of DUB activity and specificity by MALDI-TOF mass spectrometry

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    Deubiquitylases (DUBs) are key regulators of the ubiquitin system which cleave ubiquitin moieties from proteins and polyubiquitin chains. Several DUBs have been implicated in various diseases and are attractive drug targets. We have developed a sensitive and fast assay to quantify in vitro DUB enzyme activity using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Unlike other current assays, this method uses unmodified substrates, such as diubiquitin topoisomers. By analyzing 42 human DUBs against all diubiquitin topoisomers we provide an extensive characterization of DUB activity and specificity. Our results confirm the high specificity of many members of the OTU and JAMM DUB families and highlight that all USPs tested display low linkage selectivity. We also demonstrate that this assay can be deployed to assess the potency and specificity of DUB inhibitors by profiling 11 compounds against a panel of 32 DUBs

    Migraine aura: retracting particle-like waves in weakly susceptible cortex

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    Cortical spreading depression (SD) has been suggested to underlie migraine aura. Despite a precise match in speed, the spatio-temporal patterns of SD and aura symptoms on the cortical surface ordinarily differ in aspects of size and shape. We show that this mismatch is reconciled by utilizing that both pattern types bifurcate from an instability point of generic reaction-diffusion models. To classify these spatio-temporal pattern we suggest a susceptibility scale having the value [sigma]=1 at the instability point. We predict that human cortex is only weakly susceptible to SD ([sigma]<1), and support this prediction by directly matching visual aura symptoms with anatomical landmarks using fMRI retinotopic mapping. We discuss the increased dynamical repertoire of cortical tissue close to [sigma]=1, in particular, the resulting implications on migraine pharmacology that is hitherto tested in the regime ([sigma]>>1), and potentially silent aura occurring below a second bifurcation point at [sigma]=0 on the susceptible scale

    Low CD4 count plus coma predicts cryptococcal meningitis in Tanzania

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    <p>Abstract</p> <p>Background</p> <p>Largely due to the lack of diagnostic reagents, the prevalence and clinical presentation of cryptococcal meningitis in Tanzania is poorly understood. This in turn is limiting the impact of increased fluconazole availability.</p> <p>Methods</p> <p>We evaluated a cohort of 149 consecutive HIV-infected adult inpatients presenting with headache or altered mental status for clinical features, CD4 count, cryptococcal infection, and outcome. Cryptococcal meningitis was diagnosed via India ink and latex agglutination assay of CSF (<it>n </it>= 24 and 40 positive, respectively). Associations between cryptococcal meningitis and clinical features were evaluated by t-test. The sensitivity, specificity, and positive likelihood ratio of such features were determined.</p> <p>Results</p> <p>Cryptococcal meningitis was associated with confusion, social withdrawal, seizures, fever, tachycardia, meningismus, oral candidiasis, and low Glasgow coma scales and CD4 count. CD4 count < 100/μl provided the highest sensitivity for the diagnosis (93%), coma (Glasgow coma scale ≤ 8) provided the highest specificity (84%), and the combination provided the highest positive likelihood ratio (3.8). All cryptococcal meningitis patients were initiated on 800 milligrams of fluconazole daily and 50% survived to discharge, however no clinical or laboratory findings correlated with prognosis.</p> <p>Conclusion</p> <p>Cryptococcal meningitis is common among Tanzanian HIV inpatients presenting with headache or altered mental status. Purely clinical features are insensitive for establishing the diagnosis or prognosis. We advocate expanding laboratory capacity for cryptococcal antigen testing to maximize survival.</p

    Absence of Both IL-7 and IL-15 Severely Impairs the Development of CD8+ T Cell Response against Toxoplasma gondii

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    CD8+ T cells play an essential role in the protection against both acute as well as chronic Toxoplasma gondii infection. Although the role of IL-15 has been reported to be important for the development of long-term CD8+ T cell immunity against the pathogen, the simultaneous roles played by both IL-15 and related γ-chain family cytokine IL-7 in the generation of this response during acute phase of infection has not been described. We demonstrate that while lack of IL-7 or IL-15 alone has minimal impact on splenic CD8+ T cell maturation or effector function development during acute Toxoplasmosis, absence of both IL-7 and IL-15 only in the context of infection severely down-regulates the development of a potent CD8+ T cell response. This impairment is characterized by reduction in CD44 expression, IFN-γ production, proliferation and cytotoxicity. However, attenuated maturation and decreased effector functions in these mice are essentially downstream consequences of reduced number of antigen-specific CD8+ T cells. Interestingly, the absence of both cytokines did not impair initial CD8+ T cell generation but affected their survival and differentiation into memory phenotype IL-7Rαhi cells. Significantly lack of both cytokines severely affected expression of Bcl-2, an anti-apoptotic protein, but minimally affected proliferation. The overarching role played by these cytokines in eliciting a potent CD8+ T cell immunity against T. gondii infection is further evidenced by poor survival and high parasite burden in anti IL-7 treated IL-15−/− mice. These studies demonstrate that the two cytokines, IL-7 and IL-15, are exclusively important for the development of protective CD8+ T cell immune response against T. gondii. To the best of our knowledge this synergism between IL-7 and IL-15 in generating an optimal CD8+ T cell immunity against intracellular parasite or any other infectious disease model has not been previously reported
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