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1.
Jing Hu Wail M. Hassan Guorong Chen Yanlin Li Wenqiao Fan Wei Wang 《Ecological Entomology》2019,44(6):800-809
1. The Qilian Mountains represent one of the key livestock‐raising grasslands in China. The two main herbivore species raised in this area – yaks and sheep – are of critical economical value. Grasshoppers compete with these animals for available nutrients, creating multifaceted relationships between livestock, grasshoppers and plants. A clear understanding of such relationships is lacking and is urgently needed to guide conservation efforts. 2. This study aims to document the effects of yak and sheep grazing on grasshopper assemblages and to elucidate the underlying mechanisms of such effects. 3. It is shown here that yaks and sheep impact grasshopper assemblages differently. Grasshopper assemblages exhibited lower density, biodiversity, richness, and evenness of distribution in yak‐grazed pastures than in grazing‐free grasslands. Sheep‐grazed pastures exhibited a dramatically divergent picture, with elevated density, biodiversity and richness, and a slightly decreased evenness of distribution. Grasshoppers were generally larger in grazed pastures than in grazing‐free grasslands, especially in yak‐grazed plots. 4. The present study suggests that differences between yak and sheep pastures in plant assemblage structure and plant traits are probably the underlying forces driving the differences in grasshopper assemblage structure and grasshopper traits, respectively. 5. The study shows that the grasshopper habitat indicator species differ between yak and sheep pastures, raising the possibility that such indicators can be used to monitor grassland usage and degradation in the Qilian Mountains. 6. These results provide novel insights into the dynamic interactions of common domesticated herbivore species, grasshoppers and plants in Qilian Mountains, which augment current knowledge and may ultimately lead to better conservation practices. 相似文献
2.
Adnan Massadeh Ahmed Gharibeh Khaled Omari Idrees Al-Momani Ahmed Alomari Hiatham Tumah Wail Hayajneh 《Biological trace element research》2010,133(1):1-11
A total of 73 blood samples (56 from smokers and 17 from nonsmokers) were collected to determine the concentrations of selected
heavy metal in the whole blood of smokers and nonsmokers living in and around the city of Amman, Jordan. Analysis of heavy
metals in the whole blood samples of various groups took in consideration the number of cigarettes smoked per day. The analysis
of blood samples was carried out using inductively coupled plasma optical emission spectrometry. This study aimed to evaluate
the blood metal levels in smokers and nonsmokers and to assess the influence of smoking cigarettes on blood metal levels.
The results were compared with those from a control group. The results indicated that the average concentrations of cadmium
(Cd), lead (Pb), copper (Cu), zinc (Zn), and selenium (Se) were 0.0313, 0.344, 2.328, 3.214, and 0.332 mg/L, respectively.
Statistical analysis of results indicated that these average concentrations were significantly higher compared with the average
concentrations in nonsmokers (P < 0.05). Moreover, the correlations between blood metal and other blood metal levels in smokers, the correlations between
blood metal and other blood metal levels in nonsmokers, and the correlations between blood metal concentration in smokers
and its concentration in nonsmokers were calculated. The standard reference material (blood serum National Institute of Standards
and Technology 1598) and the quality control were used to validate the reliability of the method used for the estimation of
heavy metals in blood samples. Results revealed that there was an agreement between the certified values and the measured
values. 相似文献
3.
4.
Hashimi M. Wail Thornton Jon D. Downey James M. Cohen Michael V. 《Molecular and cellular biochemistry》1998,186(1-2):19-25
Exogenously administered adenosine agonist will protect myocardium against infarction during ischemia. However, long-term exposure to adenosine agonists is associated with loss of this protection. To determine why this protection is lost, isolated, perfused rabbit hearts were studied after administration of R(-)-N6-(2-phenylisopropyl)adenosine (PIA), 0.25 mg/h IP, for 3-4 days to intact animals. All hearts experienced 30 min of regional ischemia and 120 min of reperfusion. Control groups 1 and 2 were untreated. In group 1 this ischemia/reperfusion was the only intervention, whereas group 2 hearts were preconditioned with a cycle of 5 min global ischemia/10 min reperfusion preceding the 30 min regional ischemia. Groups 3-5 had been chronically exposed to PIA. Group 3 hearts had 1 preconditioning ischemia/reperfusion cycle before the prolonged ischemia. Group 4 received a 5 min infusion of 0.1 mol/L phenylephrine in lieu of global ischemia, whereas group 5 was instead treated with 1 mol/L carbachol. Infarct size averaged 32% of the risk zone in group 1, whereas ischemic preconditioning limited infarction to 8.2 in group 2. Prolonged exposure of group 3 hearts to PIA resulted in the inability of preconditioning with 5 min global ischemia to protect (28.7 ± 4.4% infarction). However, protection was restored by either phenylephrine, an agonist of 1-adrenergic receptors which couple to Gq and stimulate PKC, or carbachol, an agonist of M2-muscarinic receptors which couple instead to Gi as do adenosine A1 receptors (5.2 ± 1.7% and 9.2 ± 2.1% infarction, resp.). Therefore, cross tolerance to ischemic preconditioning develops after chronic PIA infusion. Since both the Gi and the PKC components of the preconditioning pathway were shown to be intact, tolerance must have been related to downregulation or desensitization of the A1 adenosine receptor. 相似文献
5.
Methods To Increase Fidelity of Repetitive Extragenic Palindromic PCR Fingerprint-Based Bacterial Source Tracking Efforts 总被引:3,自引:2,他引:1 下载免费PDF全文
The goal of the study was to determine which similarity coefficient and statistical method to use to produce the highest rate of correct assignment (RCA) in repetitive extragenic palindromic PCR-based bacterial source tracking. In addition, the use of standards for deciding whether to accept or reject source assignments was investigated. The use of curve-based coefficients Cosine Coefficient and Pearson's Product Moment Correlation yielded higher RCAs than the use of band-based coefficients Jaccard, Dice, Jeffrey's x, and Ochiai. When enterococcal and Escherichia coli isolates from known sources were used in a blind test, the use of maximum similarity produced consistently higher RCAs than the use of average similarity. We also found that the use of a similarity value threshold and/or a quality factor threshold (the ratio of the average fingerprint similarity within a source to the average similarity of this source's isolates to an unknown) to decide whether to accept source assignments of unknowns increases the reliability of source assignments. Applying a similarity value threshold improved the overall RCA (ORCA) by 15 to 27% when enterococcal fingerprints were used and 8 to 29% when E. coli fingerprints were used. Applying the quality factor threshold resulted in a 22 to 32% improvement in the ORCA, depending on the fingerprinting technique used. This increase in reliability was, however, achieved at the expense of decreased numbers of isolates that were assigned a source. 相似文献
6.
Wail M. Haroon Christine Pages Jean-Michel Vassal Abdalla M. Abdalla My-hanh Luong-Skovmand Michel Lecoq 《Biocontrol Science and Technology》2011,21(3):353-366
The in vitro compatibility of Metarhizium acridum strain IMI 330189 with different concentrations of Neem seed oil Azadirachta indica A. Juss. was investigated under laboratory conditions. Water, diesel and ground nut oil dilutions of M. acridum were inoculated into semi-synthetic culture medium with Neem oil and incubated for 10 days at 20, 28, and 34°C. Fungus vegetative growth and conidia production were estimated and compatibility calculated according to the in vitro classification model [T]. Field tests were also conducted during two successive years, where fourth instar nymphs of the Tree Locust, Anacridium melanorhodon melanorhodon, were sprayed with Metarhizium, Metarhizium/Neem mixture, Neem, or Malathion, on a plantation of Acacia senegal. Samples of the treated nymphs were taken 24 h after application, placed in cages and their mortality observed daily for 3 weeks. The compatibility test revealed that at 28°C, all Neem concentrations below 2% were compatible with M. acridum and concentrations of 2 and 2.5% were moderately toxic, while at 20°C, 1.0% Neem was not compatible with the fungus. In the field, Metarhizium+Neem resulted in 74 and 92% mortality during two successive years compared to 64 and 83% for Metarhizium alone. These findings clearly reveal that Neem concentration on the mixture could be increased to just under 1.0% Neem without negative impact on the fungus and that mixing Metarhizium with small quantities of Neem oil accelerates locust mortality and increases efficacy. 相似文献
7.
Othman Soufan Wail Ba-alawi Moataz Afeef Magbubah Essack Valentin Rodionov Panos Kalnis Vladimir B. Bajic 《PloS one》2015,10(12)
High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare. 相似文献
8.
BackgroundAutism is a neurodevelopmental disorder that displays significant heterogeneity. Comparison of subgroups within autism, and analyses of selected biomarkers as measure of the variation of the severity of autistic features such as cognitive dysfunction, social interaction impairment, and sensory abnormalities might help in understanding the pathophysiology of autism.ResultsWhile none of the studied markers correlated with CARS and SRS as measure of cognitive and social impairments, six markers significantly correlated with sensory profiles of autistic patients. Multiple regression analysis identifies a combination of PGES, mPGES-1, and PE as best predictors of the degree of sensory profile impairment. Library identification resulted in 100% correct assignments of both autistic and control participants based on either set 1 or 2 biomarkers together with a satisfactory rate of assignments in case of sensory profile impairment using different sets of biomarkers.ConclusionThe two selected sets of biomarkers were effective to separate autistic from healthy control subjects, demonstarting the possibility to accurately predict the severity of autism using the selected biomarkers. The effectiveness of the identified libraries lied in the fact that they were helpful in correctly assigning the study population as control or autistic patients and in classifying autistic patients with different degree of sensory profile impairment. 相似文献
9.
David Kamanda Ngugi Jochen Blom Intikhab Alam Mamoon Rashid Wail Ba-Alawi Guishan Zhang Tyas Hikmawan Yue Guan Andre Antunes Rania Siam Hamza El Dorry Vladimir Bajic Ulrich Stingl 《The ISME journal》2015,9(2):396-411
The bottom of the Red Sea harbors over 25 deep hypersaline anoxic basins that are geochemically distinct and characterized by vertical gradients of extreme physicochemical conditions. Because of strong changes in density, particulate and microbial debris get entrapped in the brine-seawater interface (BSI), resulting in increased dissolved organic carbon, reduced dissolved oxygen toward the brines and enhanced microbial activities in the BSI. These features coupled with the deep-sea prevalence of ammonia-oxidizing archaea (AOA) in the global ocean make the BSI a suitable environment for studying the osmotic adaptations and ecology of these important players in the marine nitrogen cycle. Using phylogenomic-based approaches, we show that the local archaeal community of five different BSI habitats (with up to 18.2% salinity) is composed mostly of a single, highly abundant Nitrosopumilus-like phylotype that is phylogenetically distinct from the bathypelagic thaumarchaea; ammonia-oxidizing bacteria were absent. The composite genome of this novel Nitrosopumilus-like subpopulation (RSA3) co-assembled from multiple single-cell amplified genomes (SAGs) from one such BSI habitat further revealed that it shares ∼54% of its predicted genomic inventory with sequenced Nitrosopumilus species. RSA3 also carries several, albeit variable gene sets that further illuminate the phylogenetic diversity and metabolic plasticity of this genus. Specifically, it encodes for a putative proline-glutamate ‘switch'' with a potential role in osmotolerance and indirect impact on carbon and energy flows. Metagenomic fragment recruitment analyses against the composite RSA3 genome, Nitrosopumilus maritimus, and SAGs of mesopelagic thaumarchaea also reiterate the divergence of the BSI genotypes from other AOA. 相似文献
10.
The globus pallidus (GP) receives dopaminergic afferents from the pars compacta of substantia nigra and several studies suggested that dopamine exerts its action in the GP through presynaptic D2 receptors (D2Rs). However, the impact of dopamine in GP on the pallido-subthalamic and pallido-nigral neurotransmission is not known. Here, we investigated the role of dopamine, through activation of D2Rs, in the modulation of GP neuronal activity and its impact on the electrical activity of subthalamic nucleus (STN) and substantia nigra reticulata (SNr) neurons. Extracellular recordings combined with local intracerebral microinjection of drugs were done in male Sprague-Dawley rats under urethane anesthesia. We showed that dopamine, when injected locally, increased the firing rate of the majority of neurons in the GP. This increase of the firing rate was mimicked by quinpirole, a D2R agonist, and prevented by sulpiride, a D2R antagonist. In parallel, the injection of dopamine, as well as quinpirole, in the GP reduced the firing rate of majority of STN and SNr neurons. However, neither dopamine nor quinpirole changed the tonic discharge pattern of GP, STN and SNr neurons. Our results are the first to demonstrate that dopamine through activation of D2Rs located in the GP plays an important role in the modulation of GP-STN and GP-SNr neurotransmission and consequently controls STN and SNr neuronal firing. Moreover, we provide evidence that dopamine modulate the firing rate but not the pattern of GP neurons, which in turn control the firing rate, but not the pattern of STN and SNr neurons. 相似文献