31 research outputs found

    Exponentially Weighted Moving Averages of Counting Processes When the Time between Events Is Weibull Distributed

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    There are control charts for Poisson counts, zero-inflated Poisson counts, and over dispersed Poisson counts (negative binomial counts) but nothing on counting processes when the time between events (TBEs) is Weibull distributed. In our experience the in-control distribution for time between events is often Weibull distributed in applications. Counting processes are not Poisson distributed or negative binomial distributed when the time between events is Weibull distributed. This is a gap in the literature meaning that there is no help for practitioners when this is the case. This book chapter is designed to close this gap and provide an approach that could be helpful to those applying control charts in such cases

    Selective production of light olefins from methanol over desilicated highly siliceous ZSM-5 nanocatalysts

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    Highly siliceous ZSM-5 nanocatalysts can dehydrate methanol to a wide range of hydrocarbons. In this study, the development of hierarchical H-ZSM-5 nanocatalysts (Si/Al=200) were reported for the methanol-toolefins (MTO) reaction. The nanocatalysts were prepared through a hydrothermal technique and treated by NaOH desilication. The parent and desilicated nanocatalysts were characterized using FE-SEM, XRD, FTIR, NH3-TPD and N2 adsorption-desorption techniques. The mesoporosity increased five times without significant collapse of the crystalline framework as a result of the appropriate desilication of H-ZSM-5 nanocatalyst. For the nanocatalyst, a high surface area of 189.5 m2 g-1, mesopore volume of 0.35 cm3 g-1 and well-adjusted strong acidity of 0.16 mmol NH3 g-1 resulted in a high methanol conversion of 100%, high propylene selectivity of 43% and low light paraffins selectivity o

    Determination of the Effect of Co-cultivation on the Production and Root Exudation of Flavonoids in Four Legume Species Using LC–MS/MS Analysis

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    Flavonoids play a key role in the regulation of plant−plant and plant−microbe interactions, and factors determining their release have been investigated in most of the common forage legumes. However, little is known about the response of flavonoid production and release to co-cultivation with other crop species. This study investigated alterations in the concentration of flavonoids in plant tissues and root exudates in four legumes [alfalfa (Medicago sativa L.), black medic (Medicago polymorpha L.), crimson clover (Trifolium incarnatum L.), and subterranean clover (Trifolium subterraneum L.)] co-cultivated with durum wheat [ Triticum turgidum subsp. durum (Desf.) Husn.]. For this purpose, we carried out two experiments in a greenhouse, one with glass beads as growth media for root exudate extraction and one with soil as growth media for flavonoid detection in shoot and root biomass, using LC−MS/MS analysis. This study revealed that interspecific competition with wheat negatively affected legume growth and led to a significant reduction in shoot and root biomass compared with the same legume species grown in monoculture. In contrast, the concentration of flavonoids significantly increased both in legume biomass and in root exudates. Changes in flavonoid concentration involved daidzein, genistein, medicarpin, and formononetin, which have been found to be involved in legume nodulation and regulation of plant−plant interaction. We hypothesize that legumes responded to the co-cultivation with wheat by promoting nodulation and increasing exudation of allelopathic compounds, respectively, to compensate for the lack of nutrients caused by the presence of wheat in the cultivation system and to reduce the competitiveness of neighboring plants. Future studies should elucidate the bioactivity of flavonoid compounds in cereal-legume co-cultivation systems and their specific role in the nodulation process and inter-specific plant interactions such as potential effects on weeds

    The preventive effects of natural adjuvants, G2 and G2F on tracheal responsiveness and serum IL-4 and IFN-? (th1/th2 balance) in sensitized guinea pigs

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    OBJECTIVE: The effects of natural adjuvants on lung inflammation and tracheal responsiveness were examined in sensitized guinea pigs. METHODS: The responses of guinea pig tracheal chains and the serum levels of interleukin-4 and interferon-gamma were examined in control pigs and three other groups of guinea pigs: the sensitized group and two other sensitized groups treated with either adjuvant G2 or adjuvant G2F (n = 7 for each group). Sensitization of the animals was achieved by injection and inhalation of ovalbumin. RESULTS: The results showed that sensitized animals had increased tracheal responsiveness and increased serum levels of interleukin-4 and interferon-gamma compared to controls (

    Exosomes from Adipose Tissue-derived Mesenchymal Stem Cells Induce Regulatory T Cells in COVID‐19 Patients

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    An imbalance between regulatory T (Treg) and T-helper (Th)-17 cells has been implicated in the pathogenesis of coronavirus disease 2019 (COVID-19). Mesenchymal stem cells (MSCs) exert immunomodulatory properties through secreting exosomes. This study aimed to assess the effect of MSC-derived exosomes (MSC-Exo) on the differentiation of peripheral blood mononuclear cells (PBMCs) into  Tregs from patients with COVID-19. Exosomes were isolated from adipose tissue–derived MSCs. PBMCs were separated from the whole blood of COVID-19 patients (n=20). Treg frequency was assessed before and 48 hours after treatment of PBMCs with MSC-Exo using flow cytometry. Expression of FOXP3 and cytokine genes, and the concentration of cytokines associated with Tregs, were assessed before and after treatment with MSC-Exo. The frequency of CD4+CD25+CD127-  Tregs was significantly higher after treating PBMCs with MSC-Exo (6.695±2.528) compared to before treatment (4.981±2.068). The expressions of transforming growth factor (TGF)-ÎČ1, interleukin (IL)-10, and FOXP3 were significantly upregulated in MSC-Exo–treated PBMCs. The concentration of IL‐10 increased significantly after treatment (994.7±543.9 pg/mL) of PBMCs with MSC-Exo compared with before treatment (563.5±408.6 pg/mL). The concentration of TGF-ÎČ was significantly higher in the supernatant of PBMCs after treatment with MSC-Exo (477.0±391.1 pg/mL) than PBMCs before treatment (257.7±226.3 pg/mL). MSC-Exo has the potential to raise anti-inflammatory responses by induction of  Tregs, potentiating its therapeutic effects in COVID-19

    Effective Parameters on Increasing Filamentous Bacteria and Their Effects on Membrane Fouling in MBR

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    Over 90 percent of the wastewater treatment plants in Iran use activated sludge process. Due to increase in organic loading rates, most of these plants do not have appropriate performance. For upgrading these systems and decreasing production of the excess sludge, a UASB reactor can be used as pretreatment for decreasing the organic loading prior to the activated sludge system. Also for improving the effluent quality, a membrane can be replaced for secondary sedimentation tank, i.e. changing activated sludge to membrane bioreactor. In this study, the effect of significant changes in feed composition, due to the introduction of UASB reactor; have been investigated on the population of filamentous bacteria, COD and TS removal efficiency and membrane fouling. The results showed that the population of filamentous bacteria increased rapidly from 5 to 100 Count/”L. However, this increase does not have considerable effect on membrane fouling. With increasing MLSS concentration, the number of filamentous bacteria increased from 100 to 400Count/”L. As a result, the trans membrane pressure was raised from 1.5 to 3kpa and overall membrane resistance was increased against the effluent flux. For reducing the filamentous bacteria, a dose of 20 g Cl2 /Kg MLSS was added in few intervals for two days. It was also found the number of filamentous bacteria decreased from 400 to 100 after 5 days without decreasing the other microorganisms’ population significantly. The trans membrane pressure was also retained without any further increase

    Hydophilic polypropylene microporous membrane for using in a membrane bioreactor system and optimization of preparation conditions by response surface methodology

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    In this study, the response surface methodology (RSM) based on the central composite design (CCD) was used to optimize the preparation condition of polypropylene-grafted maleic anhydride (PP-g-MA) microporous membrane by thermally-induced phase separation (TIPS) method. A mixture of dibutyl phthalate (DBP) and dioctyl phthalate (DOP) was used as diluent. The effect of polymer composition and quenching bath temperature on the morphology and performance of the fabricated microporous membranes was investigated by using RSM. Analysis of variance (ANOVA) was used to determine which variables and interactions between variables had a significant effect on our responses. The ANOVA revealed that the bath temperature was the most significant variable associated with porosity and pure water flux responses and the polymer concentration was the most significant variable associated with tensile response. The obtained results also showed that with increasing the polymer concentration and decreasing the quenching bath temperature, the membrane porosity and pure water flux decreased, whereas the membrane tensile increased. The regression equations were reasonably validated and used to predict and optimize the performance of PP-g-MA membranes within the limits of the variables. Finally, the maximum responses (flux of 115.6 L/m2h, porosity of 62% and tensile of 1.6 MPa) were obtained under the following conditions: polymer concentration of 28.5 wt% and temperature of 329 K. Further, comparison of laboratory-made and commercial membranes in a membrane bioreactor (MBR) system showed that the rate of membrane fouling was decreased by 4.2 times

    Genetic Characterization of Fasciola Isolates from West Azerbaijan Province Iran Based on ITS1 and ITS2 Sequence of Ribosomal DNA

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    Background: Fascioliasis, caused by Fasciola hepatica and F. gigantica, has medical and economic importance in the world. Molecular approaches comparing tradi­tional methods using for identification and characterization of Fasciola spp. are precise and reliable. The aims of current study were molecular characterization of Fasciola spp. in West Azerbaijan Province, Iran and then comparative analysis of them using GenBank sequences. Methods: A total number of 580 isolates were collected from different hosts in five cities of West Azerbaijan Province, in 2014 from 90 slaughtered cattle (n=50) and sheep (n=40). After morphological identification and DNA extraction, de­signing specific primer were used to amplification of ITS1, 5.8s and ITS2 regions, 50 samples were conducted to sequence, randomly. Result: Using morphometric characters 99.14% and 0.86% of isolates identified as F. hepatica and F. gigantica, respectively. PCR amplification of 1081 bp fragment and sequencing result showed 100% similarity with F. hepatica in ITS1 (428 bp), 5.8s (158 bp), and ITS2 (366 bp) regions. Sequence comparison among current study sequences and GenBank data showed 98% identity with 11 nucleotide mismatches. However, in phylogenetic tree F. hepatica sequences of West Azerbai­jan Province, Iran, were in a close relationship with Iranian, Asian, and African isolates. Conclusions: Only F. hepatica species is distributed among sheep and cattle in West Azerbaijan Province Iran. However, 5 and 6 bp variation in ITS1 and ITS2 regions, respectively, is not enough to separate of Fasciola spp. Therefore, more studies are essential for designing new molecular markers to correct species iden­tification
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