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101.
102.
Samples of airborne particulate matter (PM2.5) were collected at a site in Lahore, Pakistan from November 2005 to January 2006. A total of 129 samples were collected using an Andersen Reference Ambient Air Sampler 2.5-400 sampler and analyzed for major ions, trace metals, and organic and elemental carbon concentrations. The data set was then analyzed by positive matrix factorization (PMF) to identify the possible sources of the atmospheric PM collected in this urban area. Six factors reproduced the PM2.5 sample compositions with meaningful physical interpretation of the resolved factors. The sources included secondary PM, diesel emissions, biomass burning, coal combustion, two-stroke vehicle exhaust, and industrial sources. Diesel and two-stroke vehicles contributed about 36%, biomass burning about 15%, and coal combustion sources around 13% of the PM2.5 mass. Nearly two thirds of the PM2.5 mass is carbonaceous material. Secondary particles contributed about 30% of PM2.5 mass. The conditional probability function (CPF) was then used to help identify likely locations of the sources present in this area. CPF analysis point to the east and northeast, which are directions of urban and industrial areas located across the border near Amritsar, India as the most probable source for high PM2.5 concentration from diesel and two-stroke vehicles exhaust in Lahore. Analysis of those days within three different ranges of PM2.5 concentration shows that most of the measured high PM2.5 mass concentrations were driven by diesel and two-stroke vehicle emissions including the associated primary sulfate. The use of the potential source contribution function (PSCF) to find the source locations of regionally transported particles is inapplicable in situations when high PM2.5 concentrations are dominated by local sources and local meteorology.  相似文献   
103.
The primary objective of this study was to assess the expression profile and levels of toll-like receptor (TLR) mRNAs in the spleen, lung, mediastinal lymph node (MLN), jejunum, rectum, skin and peripheral blood mononuclear cells (PBMC) of Toda and Murrah buffalos. Spleen and PBMC had increased expression of TLR mRNAs 2, 4, 5, 6, 8, 9 and 10; lung had increased expression of TLR mRNAs 2, 4, 5, 6 and 8, MLN TLR mRNA 6, 9, 10 and decrease in TLR 3 and 7 mRNAs in skin. No significant differences were observed in the expression levels of any of the TLR mRNA in jejunum and rectum. Toda buffaloes showed significantly higher expression levels of TLR 9 mRNA in MLN, TLR mRNAs 1, 5, 6, 9 and 10 in skin and TLR mRNAs 2, 4, 7 and 9 in PBMC than Murrah buffaloes living in the vicinity. Toda and Murrah buffaloes were inoculated with TLR5 (flagellin) and TLR9 (CpG ODN) ligands in vivo and expression levels of the respective TLRs analyzed 12h later. Following CpG inoculation, Toda buffaloes had significantly higher levels of TLR 9 mRNA expression but not in Murrah. However, flagellin induction did not increase TLR 5 mRNA expression in both these breeds. Histological sections of the skin were made and infiltrating cell clusters were graded and quantified. Following CpG inoculation, Toda buffaloes showed higher numbers of infiltrating grade 1 and grade 3 cell clusters while Murrah showed lower numbers of infiltrating grade 1 cells as compared to mock-inoculated skin sections. Flagellin treatment revealed no significant differences in infiltrating cell clusters in both the breeds. The results have shown differential expression of TLR mRNAs in various tissues between two divergent buffalo breeds with the highest difference in TLR expression profile seen in the skin, the largest portal of entry of pathogens, of Toda.  相似文献   
104.
DEEPER ROOTING 1 (DRO1) of rice controls the gravitropic response of root growth angle. In order to clarify the effects of DRO1 on root growth angle and root length density under different soil resistance to penetration, and to quantify the relationship between root growth angle and root length density, we assessed the root growth of Dro1-NIL (a near-isogenic line homozygous for the Kinandang Patong allele of DRO1 in the IR64 background) under upland Andosol field conditions in Japan in 2013 and 2014. The trial included three levels of soil compaction (none, moderate, and hard). Root length density at a depth of 30 to 60 cm was largest in Kinandang Patong, followed by Dro1-NIL, and was least in IR64 in both years and in all compaction treatments. Root length density at this depth decreased with hard compaction (to 70% of control) and increased with moderate compaction (to 135%). The number of roots with a deep angle (i.e. 45° to 90° from the horizontal) measured by the basket method was similar at maximum tillering and maturity stages, and its value as a proportion of the total number of roots was strongly correlated with the root length density at 30 to 60 cm in both years, which demonstrates the importance of a deep root angle for the development of deep roots. Dro1-NIL had a higher proportion of deep roots than IR64, but the difference was small under hard compaction, with a significant genotype × compaction interaction.  相似文献   
105.
The pharmacokinetic–pharmacodynamic (PK/PD) modeling of enrofloxacin data using mutant prevention concentration (MPC) of enrofloxacin was conducted in febrile buffalo calves to optimize dosage regimen and to prevent the emergence of antimicrobial resistance. The serum peak concentration (Cmax), terminal half‐life (t1/2K10), apparent volume of distribution (Vd(area)/F), and mean residence time (MRT) of enrofloxacin were 1.40 ± 0.27 μg/mL, 7.96 ± 0.86 h, 7.74 ± 1.26 L/kg, and 11.57 ± 1.01 h, respectively, following drug administration at dosage 12 mg/kg by intramuscular route. The minimum inhibitory concentration (MIC), minimum bactericidal concentration, and MPC of enrofloxacin against Pasteurella multocida were 0.055, 0.060, and 1.45 μg/mL, respectively. Modeling of ex vivo growth inhibition data to the sigmoid Emax equation provided AUC24 h/MIC values to produce effects of bacteriostatic (33 h), bactericidal (39 h), and bacterial eradication (41 h). The estimated daily dosage of enrofloxacin in febrile buffalo calves was 3.5 and 8.4 mg/kg against P. multocida/pathogens having MIC90 ≤0.125 and 0.30 μg/mL, respectively, based on the determined AUC24 h / MIC values by modeling PK/PD data. The lipopolysaccharide‐induced fever had no direct effect on the antibacterial activity of the enrofloxacin and alterations in PK of the drug, and its metabolite will be beneficial for its use to treat infectious diseases caused by sensitive pathogens in buffalo species. In addition, in vitro MPC data in conjunction with in vivo PK data indicated that clinically it would be easier to eradicate less susceptible strains of P. multocida in diseased calves.  相似文献   
106.
Journal of Plant Diseases and Protection - The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a polyphagous lepidopteran pest that is native to tropical and sub-tropical America has...  相似文献   
107.
Abstract

A field experiment was conducted at Research Farm of ICAR-Directorate of Groundnut Research, Junagadh for consecutive three summer seasons of 2013, 2014, and 2015 with the objectives of identifying optimum plant density and nutrient doses under check basin irrigation and drip fertigation for higher productivity and net returns. The treatments were; three plant densities viz., 3,33,333 plants/ha (100% of recommended plant density; P1); 4,16,666 plants/ha (125% of recommended plant density; P2), and 4,99,999 plants/ha (150% of recommended plant density;P3) in main plots, and three nutrient doses viz., 18.75–37.5–22.5 NPK kg ha?1 (75% of recommended nutrient dose; F1), 25-50-30 NPK kg ha?1 (100% of recommended nutrient dose; F2), and 31.25–62.5–37.5 NPK kg ha?1 (125% of recommended nutrient dose; F3) in sub-plots, and replicated thrice. The same sets of treatments were tested under both check basin irrigation and drip fertigation. The data were analyzed using split plot design. Pod yield, haulm yield, and net returns were significantly higher with P3 as compared to P1 under check basin irrigation but only haulm yield was found significantly higher with P3 under drip fertigation. Under check basin irrigation, NH4–N, NO3–N, and available P and K in soil were found in the order P1?>?P2?>?P3 (p?<?0.05) while in case of drip fertigation, differences were significant only for available K which was significantly higher in P1 over both P2 and P3. Under check basin irrigation, F2 i.e., application of 100 percent of recommended nutrient doses, being at par with F3, significantly improved pod yield, haulm yield and net returns over that with F1 however, differences were not significant under drip fertigation. NH4–N, NO3–N and available P and K in soil under both the irrigation systems were in the order F3?>?F2?>?F1 (p?<?0.05).  相似文献   
108.
The 3-O-fatty acid ester derivatives (C(12)-C(18)) of two pentacyclic triterpenic acids, ursolic acid and oleanolic acid, were synthesized under mild esterification conditions in excellent yields (80-85%) and screened for their antifeedant activity, together with the parent acids, against the agricultural pest tobacco caterpillar larvae (Spodoptera litura F) in a no-choice laboratory study. The Urs-12-ene-28-carboxy-3beta-octadecanoate and olean-12-ene-28-carboxy-3beta-hexadecanoate were found to exhibit exceptionally potent antifeedant activities at 50 microg/cm(2) concentration, even after 48 h.  相似文献   
109.
A recent dispersal of modern humans out of Africa is now widely accepted, but the routes taken across Eurasia are still disputed. We show that mitochondrial DNA variation in isolated "relict" populations in southeast Asia supports the view that there was only a single dispersal from Africa, most likely via a southern coastal route, through India and onward into southeast Asia and Australasia. There was an early offshoot, leading ultimately to the settlement of the Near East and Europe, but the main dispersal from India to Australia approximately 65,000 years ago was rapid, most likely taking only a few thousand years.  相似文献   
110.
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