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51.
Abeera Naureen Muhammad Saqib Faqeer Muhammad Rehan Ahmad Ghulam Muhammad Muhammad Nadeem Asi Muhammad Hammad Hussain Laeeq Akbar Lodhi Muhammad Sarwar Khan Francois M. Thibault 《Journal of Equine Veterinary Science》2010
Minimum inhibitory concentrations (MICs) of 20 antimicrobial agents for 41 isolates of Burkholderia mallei from natural outbreaks of equine glanders were determined by agar dilution. All isolates were intrinsically resistant to ampicillin (MIC90 ≥128). Resistance to other antimicrobials was as follows: 95.1% to amoxicillin and cephradine, 85.4% to cefuroxime and norfloxacin, 68.3% to ceftizoxime and ceftriaxone, 61.1% to ceftiofur, 58.5% to oxytetracycline, 41.5% to ciprofloxacin, 58.5% to roxithromycin, 17.1% cefotaxime, and 12.2% clarithromycin. Overall resistance patterns revealed that 17% of isolates were simultaneously resistant to amoxicillin, cephradine, cefuroxime, ceftizoxime, ceftriaxone and norfloxacin. None of the isolates were resistant to amoxicillin-clavulanic acid, doxycycline, chloramphenicol, gentamicin or trimethoprim-sulphadiazine. Mode MICs for these antimicrobials were 2, 1, 8, 4 and 1 μg/ml, respectively. A majority of the isolates (∼ 94%) were susceptible to both enrofloxacin and ofloxacin. These data provide an updated perspective on susceptibility profiles of current strains of B. mallei in an endemic area. 相似文献
52.
When performing molecular dynamics simulations for a system with constrained (fixed) atoms, traditional isobaric algorithms (e.g., NPT simulation) often cannot be used. In addition, the calculation of the internal pressure of a system with fixed atoms may be highly inaccurate due to the nonphysical nature of the atomic constraints and difficulties in accurately defining the volume occupied by the unconstrained atoms in the system. The inability to properly set and control pressure can result in substantial problems for the accurate simulation of condensed-phase systems if the behavior of the system (e.g., peptide/protein adsorption) is sensitive to pressure. To address this issue, the authors have developed an approach to accurately determine the internal pressure for a system with constrained atoms. As the first step in this method, a periodically extendable portion of the mobile phase of the constrained system (e.g., the solvent atoms) is used to create a separate unconstrained system for which the pressure can be accurately calculated. This model system is then used to create a pressure calibration plot for an intensive local effective virial parameter for a small volume cross section or "slab" of the system. Using this calibration plot, the pressure of the constrained system can then be determined by calculating the virial parameter for a similarly sized slab of mobile atoms. In this article, the authors present the development of this method and demonstrate its application using the CHARMM molecular simulation program to characterize the adsorption behavior of a peptide in explicit water on a hydrophobic surface whose lattice spacing is maintained with atomic constraints. The free energy of adsorption for this system is shown to be dramatically influenced by pressure, thus emphasizing the importance of properly maintaining the pressure of the system for the accurate simulation of protein-surface interactions. 相似文献
53.
Rafiq Ahmad Mahmood-ul- Hassan Ghanan B. Akhtar Sadia Saeed Sabaz A. Khan Muhammad Kausar Nawaz Shah Nadeem Khan 《Plant Breeding》2020,139(5):988-995
Onion is one of the major vegetable crops in terms of production as well as consumption. In the current research, available onion genetic stock was evaluated to identify male-sterile lines and produce high-yielding F1 hybrids for future breeding programmes. A mitochondrial DNA-based marker was mapped and correlated with phenotypic traits to isolate male-sterile plants. Based on the floral and pollen structure, nine putative male-sterile lines were identified. On the other hand, for nuclear marker identification at Ms locus, two sets of primers were used, one for Ms dominant allele and another for sterile and maintainer plants. Results revealed that 70% of open pollinated varieties (OPVs) possess plants with sterile cytoplasm coupled with genetic sterility at Ms locus, called sterile “A” line. Approximately 20% of plants in some genotypes were identified with normal (N) cytoplasm having recessive fertility gene at Ms locus, called maintainer “B” line. Based on the present findings, “A”, “B” and “R” (restorer line), future F1 hybrid seed production systems in onion is discussed. 相似文献
54.
Muhammad Hamayun Sumera Afzal Khan Abdul Latif Khan Nadeem Ahmad Yasmin Nawaz Hasan Sher In-Jung Lee 《Scientia Horticulturae》2011
Gibberellins production by soil fungi received little attention, although substantial work has been carried out on other growth promoting aspects of soil borne fungi. We investigated gibberellins production and growth promoting capacity of a novel fungal strain of Neosartorya, which was isolated from the roots of Chinese cabbage (Bassica rapa L. ssp. pekinensis). Fungal culture filtrates (CF) obtained from pure cultures of 16 endophytic fungi were bioassayed on Waito-C, in order to investigate plant growth promoting capacity of these fungi. The fungal isolate CC-8 induced maximum shoot length of Waito-C (13.0 cm) as compared to control treatments. In a separate experiment, the CF of fungus CC-8 significantly promoted plant length and biomass of Chinese cabbage. The fungal CF also increased endogenous bioactive GA1 and GA4 contents of Chinese cabbage. Gibberellin analysis of CF of CC-8 showed presence of both physiologically active and non active gibberellins in higher concentrations (GA1, 1.42 ng/ml; GA3, 5.93 ng/ml; GA4, 11.36 ng/ml; GA7, 3.25 ng/ml; GA9, 0.79 ng/ml; GA15, 1.18 ng/ml). The culture filtrate of CC-8 produced higher amounts of GA3, GA4, GA7 and GA9 than wild type Fusarium fujikuroi, a well known gibberellins producing fungus. The fungal isolate CC-8 was later identified as a new strain of Neosartorya species on the basis of traditional and advance molecular techniques. 相似文献
55.
Muhammad Nadeem Asghar Muhammad Kaleem Ullah Muhammad Mohsin Hafeez 《Irrigation and Drainage Systems》2008,22(3-4):239-252
Stream salinity management is of prime importance for ensuring environmental sustainability of rivers, streams, lakes and other water bodies. Saline groundwater inflows are the main cause of deteriorating quality of stream flows; especially during periods of low flows. The Murray-Darling Basin is a good example for reducing groundwater recharge from irrigated agricultural areas with successful implementation of land and water management plans (LWMPs). In most cases, these plans help minimize the influence of saline groundwater flows on the stream salinity, as a preventive measure. As a remedial measure, this paper introduces a simple but an innovative approach for regulating saline groundwater inflows to natural streams in irrigated agricultural areas. The approach uses the flap gate with an automatic lowering and raising mechanism. During low stream flow, this gate is kept in a raised position. Depending upon the upstream inflows, the ponding situation will develop hydraulic gradient away from the stream; groundwater inflows to the creek will become minimal. During high stream flows, the gate is kept in a lower position to let the diluted water flows through the stream uninterrupted. To install, operate and manage such gates on multiple sites along the stream(s), the individual control panels can be joined into a central control station via telemetric link up. This approach, which holds a key for successfully regulating groundwater induced salinity to natural streams, should be considered in conjunction with other LWMPs to improve stream salinity in an irrigated agricultural area. 相似文献
56.
Arshad Mehmood Abbasi Munir H. Shah Xinbo Guo Nadeem Khan 《International Journal of Fruit Science》2016,16(2):113-134
Ethnomedicinal uses, chemical composition (major nutrients, essential/toxic metals, phytochemical constituents), and antioxidant properties of the fruits of five Morus species (M. alba, M. laevigata, M. macroura, M. nigra, and M. serrata) were evaluated in this study. Standard methodology was used for the analysis of the nutrients, major/trace metals, phytochemicals, and antioxidant potential of the fruits. Highest average contents of the proteins (13.1%), fats (12.4%), fibers (8.02%), and carbohydrates (80.5%) were found in M. macroura, M. laevigata, M. nigra, and M. serrata, respectively. Among the metals, highest concentration in the fruits was shown by K (1080–1230 mg/kg), followed by Mg (84.4–207 mg/kg), Ca (54.8–146 mg/kg), Fe (13.6–59.0 mg/kg), Na (5.43–14.8 mg/kg), and Zn (2.15–5.57 mg/kg). The phytochemicals and antioxidant activities were measured in the water and acetone extracts of the fruits. Relatively higher total phenolics (85.6 mg GAE/100 g, FW), flavonoids (85.8 mg RE/100 g, FW), flavonols (99.8 mg RE/100 g, FW), and ascorbic acid (4.12 mg AAE/100 g, FW) contents were found in M. nigra, which also revealed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition (93.8%). Considerably higher OH radical and H2O2 scavenging activities were observed in M. macroura and M. alba, respectively. Comparatively higher ferrous ions chelating activity (37.8%) was noted in M. serrata, which also showed highest value for phosphomolybdenum assay (183 µM AAE/100 g, FW). Highest ferric ion reducing antioxidant power (69.9 µM GAE/100 g, FW) was found in M. leavigata. The Morus fruits were a good source of the nutrients, minerals, and phyotchemicals along with superior antioxidant potential. Health risk assessment showed no significant non-carcinogenic or carcinogenic health risk associated with the consumption of these fruits. 相似文献
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58.
Shoaib Akhtar Gu-cheng LI Raza Ullah Adnan Nazir Muhammad Amjed Iqbal Muhammad Haseeb Raza Nadeem Iqbal Muhammad Faisal 《农业科学学报》2018,17(6):1454-1462
Hybrid maize farmers have to face diverse kinds of climate, biological, price and financial risks. Farmers' risk perceptions and risk attitudes are essential elements influencing farm operations and management decisions. However, this important issue has been overlooked in the contemporary studies and therefore there is a dearth of literature on this important issue. The present research is therefore, an attempt to fill this gap. This study aims to quantify hybrid maize farmers' perceptions of disastrous risks, their attitudes towards risk and to explore the impacts of various farm and farm household factors on farmers' risk attitudes and risk perceptions. The present study is conducted in four hybrid maize growing districts of Punjab Province, Pakistan, using cross-sectional data of 400 hybrid maize farmers. Risk matrix and equally likely certainty equivalent (ELCE) method are used to rank farmers' perceptions of four catastrophic risk sources including climate, biological, price and financial risks and to investigate farmers' risk aversion attitudes, respectively. Furthermore, probit regression is used to analyze the determinants affecting farmers' risk attitudes and risk perceptions. The results of the study showed that majority of farmers are risk averse in nature and perceive price, biological and climate to be potential sources of risks to their farm enterprise. In addition, analysis divulges that distance from farm to main market, off-farm income, location dummies for Sahiwal and Okara, age, maize farming experience, access to extension agent, significantly (either negatively or positively) influence farmers' risk attitudes and risk perceptions. The study delivers valuable insights for farmers, agricultural insurance sector, extension services researchers and agricultural policy makers about the local understanding of risks to hybrid maize crop in developing countries, like Pakistan, and have implications for research on farmers' adaptation to exposed risks. 相似文献
59.
Phosphorous (P) and zinc (Zn) are plant nutrients that interact with each other in soil–plant systems. Such interactions may cause deficiency of one of the nutrients interacting with each other if interactions are antagonistic. In the present trial, a field experiment was conducted to investigate the interactive effect of Zn (0 and 16 kg ha?1) and P (0 and 60 kg ha?1) on growth, yield and grain Zn concentration of two maize (Zea mays L.) genotypes, i.e., Neelam (local) and DK‐6142 (hybrid). Growth and yield of both maize genotypes were increased by the application of Zn and P treatments compared with control, but Zn+P was more effective than their sole application. When compared to control, combined application of Zn+P increased grain Zn and P concentrations by 52% and 32%, respectively, averaged for the two genotypes. Single application of P decreased grain Zn concentration by 10% over control. Application of P and Zn particularly in combination decreased the grain [phytate] : [Zn] ratio and increased the estimated human Zn bioavailability in grains based on a trivariate model of Zn absorption in both maize genotypes. Conclusively, combined Zn+P application appeared more suitable for enhancing grain yield and agronomic Zn biofortification in maize grains. However, Zn fertilization aiming at increasing grain yield and grain Zn concentration should consider the genotypic variations and P rate. 相似文献
60.
Mazhar Abbas Raziya Nadeem Muhammad Nadeem Zafar Mamoona Arshad 《Water, air, and soil pollution》2008,191(1-4):139-148
The present study explained the effect of pretreatments on the biosorption of Cr (III) and Cr (VI) by Cassia fistula biomass from aqueous solutions. For this purpose Cassia fistula biomass was pretreated physically by heating, autoclaving, boiling and chemically with sodium hydroxide, formaldehyde, gluteraldehyde, acetic acid, hydrogen peroxide, commercial laundry detergent, orthophosphoric, sulphuric acid, nitric acid, and hydrochloric acid. The adsorption capacity of biomass for Cr (III) and Cr (VI) was found to be significantly improved by the treatments of gluteraldehyde (95.41 and 96.21 mg/g) and benzene (85.71 and 90.81 mg/g) respectively. The adsorption capacity was found to depend on pH, initial metal concentration, dose, size, kinetics, and temperature. Maximum adsorption of both the Cr (III) and Cr (VI) was observed at pH 5 and 2. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The kinetic studies showed that the sorption rates could be described better by a second order expression than by a more commonly applied Lagergren equation. 相似文献