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41.
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Sayed M. Riyadh Shojaa A. El‐Motairi Hany E. A. Ahmed Khaled D. Khalil EL‐Sayed E. Habib 《化学与生物多样性》2018,15(9)
2‐(1‐{4‐[(4‐Methylphenyl)sulfonamido]phenyl}ethylidene)thiosemicarbazide ( 3 ) was exploited as a starting material for the synthesis of two novel series of 5‐arylazo‐2‐hydrazonothiazoles 6a – 6j and 2‐hydrazono[1,3,4]thiadiazoles 10a – 10d , incorporating sulfonamide group, through its reactions with appropriate hydrazonoyl halides. The structures of the newly synthesized products were confirmed by spectral and elemental analyses. Also, the antimicrobial, anticancer, and DHFR inhibition potency for two series of thiazoles and [1,3,4]thiadiazoles were evaluated and explained by molecular docking studies and SAR analysis. 相似文献
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Hila Shamoon Shlomo Cain Uri Shanas Avi Bar-Massada Yariv Malihi Idan Shapira 《European Journal of Wildlife Research》2018,64(3):35
Recreation activities in developed landscapes may add additional stressors that affect wildlife spatial and temporal activity patterns. We assessed medium to large mammal species response to a tourist scenic route in an agro-ecological mosaic landscape of the Shikma region, Israel. We placed 60 camera traps in an agro-ecological matrix and recorded mammals during three seasons between 2015 and 2017. We used N-mixture models to estimate mammal activity in relation with proximity to the scenic route and additional anthropogenic related factors such as traffic volume and land use. Anthropogenic development and activities had negative effects on large, endangered species, and none or positive on smaller, commensal species. Our results suggest an expansion of human recreation activity may have adverse outcomes on apex predators, which can cause a chain reaction and lead to meso-predator release, ultimately affecting prey species. The results emphasize the need for land managers to be extra cautious when attempting to add additional stressors (i.e., recreation activity) to developed landscapes such as the study area. Such landscapes can function as healthy ecosystems and provide suitable habitats for wildlife given that land managers are aware and account for wildlife-limiting factors in future development plans. 相似文献
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Lamia Sakouhi Sondès Rahoui Marouane Ben Massoud Shintaro Munemasa Ezzeddine EL Ferjani Yoshiyuki Murata Abdelilah Chaoui 《Journal of Plant Growth Regulation》2016,35(4):1064-1073
Impact of exogenous calcium and ethylene glycol tetraacetic acid (EGTA) supplement on chickpea (Cicer arietinum L.) germinating seeds exposed to cadmium stress for 6 days was studied. Ca and EGTA late treatment (3 days) alleviated growth inhibition and decreased Cd accumulation as well as lipid peroxidation and protein carbonylation in both root and shoot cells. Exogenous effector application relieved Cd-induced cell death which was associated with a constant level of ATP, which was considered as an apoptotic-like process. Redox balance was examined through the study of the redox state of pyridine nucleotide couples NAD+/NADH and NADP+/NADPH as well as their related oxidative [NAD(P)H-oxidase] and dehydrogenase (glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malate dehydrogenase) enzyme activities. The present research illustrated an ameliorative effect of Ca and EGTA on growth of Cd-exposed chickpea seedlings that occurs through the protection of sensitive cell sites from Cd-induced oxidation, namely membrane lipids and proteins, rather than the improvement of recycling capabilities of the cellular reducing power. 相似文献
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Crown-gall tumor initiation by Agrobacterium tumefaciens (SMITHand TOWN.) CONN, strain B6, on Phaseolus vulgaris L. var. "Pinto"was found to be sensitive to the addition of various salts tothe freshly inoculated primary leaves. Calcium, magnesium, zincand ammonium sulfates, cobalt and nickel chlorides and potassiumnitrate increased the number of tumors on inoculated leavesby 100 to 200 percent. Maximal promotions were obtained at concentrationsof 107 to 105 M with all of these salts exceptpotassium nitrate which was most active at 102M. Sodium,potassium, calcium, magnesium and aluminum chlorides, and sodium,potassium and nickel sulfates had little or no effect on tumorinitiation. The combination of sodium sulfate with magnesiumchloride gave promotions comparable to those obtained with magnesiumsulfate, indicating that both the magnesium and sulfate ionswere necessary for the promotion obtained with this latter salt.Combining any two of the active salts at their optimum concentrationsfor promotion resulted in a reciprocal inhibition of the promotionobtained with either salt alone, suggesting these salts to beactive by different and potentially antagonistic mechanisms.The possible nature of these promotions is discussed, but theyremain too obscure to warrant a specific proposal for theirmode of action.
1Present adress: Department of Botany, University of Khartoum,Khartoum, Sudan. 相似文献
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Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
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This study demonstrates that Pleistophora schubergi Zwölfer, 1927, a microsporidium originally isolated from the midgut epithelium of Nygmia phaeorrhoea Don (Euproctis chrysorrhoea L.) and Porthetria dispar L., and subsequently reported in several other insects including the spruce budworm, Choristoneura fumiferana (the host used in this investigation), does not belong in the genus Pleistophora Gurley, 1893. Pleistophora schubergi lacks the major features that are characteristic of Pleistophora typicalis, the type species of this genus. A comparison of ultrastructural observations reported for the type species of the genus Pleistophora, P. typicalis, and our observations of P. schubergi revealed significant differences. A thick (0.5 μm) amorphous coat, derived from parasite secretions and deposited external to the parasite plasmalemma, surrounds all developmental stages in P. typicalis. Double membranes, derived from host rough endoplasmic reticulum cisternae encircle the parasite plasmalemma of all developmental stages in P. schubergi. The sporophorous vesicle encases the spores in P. typicalis, and originates from the parasite-secreted coat that is present around meronts. In P. schubergi, the host endoplasmic reticulum cisternae form the envelope that surrounds the meronts. Moreover, the sporophorous vesicle envelope in P. typicalis persists around groups of spores, while in P. schubergi this envelope breaks easily to release the spores in the host cytoplasm. By comparing the characteristics of the microsporidium found in the spruce budworm with those of the recently created polysporous genera that sporulate within a vesicle, we found that P. schubergi does belong in the new genus Endoreticulatus Brooks et al. 1988, and consequently rename it Endoreticulatus schubergi (Zwölfer, 1927) n. comb. 相似文献