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In recent years, grapevine trunk diseases have gained growing attentions due to worldwide incidence of the disease. In a survey on fungal agents associated with grapevine trunk diseases in northern Iran, wood samples were collected from grapevines having the symptoms of declination. Isolation was made using routine plant pathology methods. A coelomycetous fungus with appendage-bearing conidia was recovered from symptomatic tissues. Based on morphological and cultural characteristics, the causal agent of the disease was identified as Truncatella angustata. The identity of the species was further confirmed by sequence data of internal transcribed spacer-rDNA region. A phylogeny inferred using sequence data obtained in this study, together with the sequences from GenBank, clustered our isolates together with T. angustata known from other host plant species. Pathogenicity tests performed on detached shoots of grapevines led to the same symptoms as observed in field conditions. This is first study on the pathogenicity of T. angustata on grapevine in Iran and first report on the occurrence of T. angustata on grapevine in Iran.  相似文献   
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Lut desert is situated in one of the extremely arid climatic zones of Iran and is one of the hottest deserts in our plant with the extreme fluctuation of temperature over a day. The main objective of this study is to characterize the diversity of the culturable actinomycetes and preliminary evaluation of their extracts as antimicrobial components on drug resistant pathogens. Twenty-four soil samples were collected, successively diluted and inoculated into the different culture media to support the growth of most culturable bacteria including actinomycetes. Phenotypic and molecular methods were used for accurate identification of recovered isolates particularly actinomycetes at the genus and species levels. The isolates were also evaluated for their inhibitory activities against drug resistant Acinetobacter baumannii, Enterococcus faecium, Klebsiella pneumoniae and Staphylococcus aureus. A total of 56 isolates recovered from the samples. Based on phenotypic tests, 41 isolates were identified as actinomycetes, amongst them 8 isolates were active against drug resistant pathogens. Our study revealed Lut desert, as one of the hottest deserts in the world, is the habitat to diverse taxa of bacteria particularly actinomycetes which have potential novel antimicrobial components.

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The study was conducted to investigate the effect of growth-promoting bacteria (Azotobacter vinelandii?=?A, Pantoea agglomerans?+?P. putida?=?P, combined A?+?P, control) on the germination, growth and nutrient uptake of Onobrychis sativa L. under drought stress (field capacity (FC), 0.7?FC, 0.4?FC). The results showed that the highest and lowest germination rate (GR) was related to the P and control treatments in FC level, respectively. The maximum root and shoot length at the FC level was related to the treatment A. In the A?+?P treatment, the maximum shoot dry weight was measured in 0.7?FC level. The lowest root dry weight was also related to the A?+?P treatment in the FC level. Bio-fertilizers had the maximum impact in increasing the nutrients uptake in 0.7?FC and FC levels. The fertilizers in 0.7?FC and FC levels increased the plant traits and played no significant role in mitigating the effects of drought stress.  相似文献   
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Leishmaniasis is a worldwide uncontrolled parasitic disease due to the lack of effective drug and vaccine. To speed up effective drug development, we need powerful methods to rapidly assess drug effectiveness against the intracellular form of Leishmania in high throughput assays. Reporter gene technology has proven to be an excellent tool for drug screening in vitro. The effects of reporter proteins on parasite infectivity should be identified both in vitro and in vivo. In this research, we initially compared the infectivity rate of recombinant Leishmania major expressing stably enhanced green fluorescent protein (EGFP) alone or EGFP-luciferase (EGFP-LUC) with the wild-type strain. Next, we evaluated the sensitivity of these parasites to amphotericin B (AmB) as a standard drug in 2 parasitic phases, promastigote and amastigote. This comparison was made by MTT and nitric oxide (NO) assay and by quantifying the specific signals derived from reporter genes like EGFP intensity and luciferase activity. To study the amastigote form, both B10R and THP-1 macrophage cell lines were infected in the stationary phase and were exposed to AmB at different time points. Our results clearly revealed that the 3 parasite lines had similar in vitro infectivity rates with comparable parasite-induced levels of NO following interferon-γ/lipopolysaccharide induction. Based on our results we proposed the more reporter gene, the faster and more sensitive evaluation of the drug efficiency.  相似文献   
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Background: COVID-19 is associated with higher mortality rates in patients with cancer. In this study, we aimed to evaluate the clinical outcomes, and laboratory and imaging data of patients with solid tumor infected with COVID-19 infection. Methods: This is a cross-sectional retrospective study performed in 2020-2022 on 85 patients with a previous diagnosis of solid tumors infected with COVID-19. We included all patients with tumors of solid organs that were diagnosed with COVID-19 infection and required hospitalization those patients previously hospitalized for treatments and were infected with COVID-19 during hospitalization. Demographic data of patients were collected using a checklist. We collected data regarding clinical outcome (discharge, hospitalization or death), duration of hospitalization, requiring ICU admission, duration of hospitalization divided by received drugs and type of tumor and mean survival time. Furthermore, we collected laboratory data from all patients. The radiologic characteristics of patients were also extracted from their data. Results: Breast cancer was the most common solid tumor (34.9%), followed by lung cancer (19.3%). The mortality rate was 24.1% (20 patients). The highest mortality rate in this study was for metastatic intestinal cancer to the lung (100%, one patient), followed by metastatic prostatic cancer to lung (50%, three patients). The highest hospitalization duration was for patients with glioblastoma multiform (GBM) (30 days). The mean survival time among patients with mortality was 19.15±1.80 days. The mean CT severity score of all patients was 27.53±22.90. Patient’s most common radiologic sign was air space consolidation (89.1%). The highest CT severity score was found in patients with stomach cancer (46.67±5.77). Conclusion: The mortality rate in this study was 24.1%. Based on the results of our study and previous research, special care should be provided to patients with solid tumors during the COVID-19 pandemic and in infected cases.  相似文献   
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Growth chamber and field experiments were carried out to determine the effects of extended photoperiod under low and freezing temperatures on bermudagrass turf dormancy at Bajgah, in the southern part of Iran. The experiment in the growth chamber was conducted with four temperature regimes (15, 7.5, 0 and -7.5°C) and three light durations (8, 12 and 16h) in a completely randomized design with four replications. The field study was conducted in two consecutive years (2008-2009) with three light durations (8, 12 and 16h) in months with natural short day length and arranged in a randomized complete blocks design with three replications. Results in both experiments showed that decreasing temperature and photoperiod decreased verdure fresh and dry weight, shoot height, tiller density, leaf area and chlorophyll and relative water contents (RWC). However, rooting depth and fresh weight of roots increased in the growth chamber. Decreasing the temperature and light duration increased electrolyte leakage and proline content. Reducing sugars increased with decreasing temperature and declined with lowering light duration in both shoots and roots. Starch content of both shoots and roots showed an adverse trend compared to reducing sugars; starch content increased in both shoots and roots in all treatments by shortening the photoperiod. Practically, the problem of bermudagrass turf's dormancy could be solved via increasing the photoperiod in months with short day lengths. This treatment would be efficient and useful for turfgrass managers to apply in landscapes and stadiums.  相似文献   
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The problem of constrained workflow scheduling on heterogeneous computing systems has been of major interest in the recent years. The user requirements are described by defining constraints on the workflow makespan and/or its execution cost. The uncertainty in the activity execution path and the dynamicity in the resource workload may cause some run-time changes of the makespan or cost. To prohibit run-time constraint violation, the system needs robust schedules. In this paper, probability of violation (POV) of constraints is proposed as a criterion for the schedule robustness. An ant colony system is then used to minimize an aggregation of violation of constraints and the POV. Simulation results on real world workflows show the effectiveness of the proposed method in finding feasible schedules. The results also indicate that the proposed method decreases the POV, as well as the expected penalty at run-time.  相似文献   
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