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51.
Bogan Mustafa Al Behcet Kul Seval Zengin Suat Oktay Murat Sabak Mustafa Gümüşboğa Hasan Bayram Hasan 《International journal of biometeorology》2021,65(10):1733-1739
International Journal of Biometeorology - Epidemiological studies have suggested an association between particulate air pollution, increased temperatures, and morbidity related to pregnancy... 相似文献
52.
Yufei Li Chenkun Yang Hasan Ahmad Mohamed Maher Chuanying Fang Jie Luo 《植物学报(英文版)》2021,63(1):210-227
Vitamins maintain growth and development in humans, animals, and plants. Because plants serve as essential producers of vitamins, increasing the vitamin contents in plants has become a goal of crop breeding worldwide. Here, we begin with a summary of the functions of vitamins. We then review the achievements to date in elucidating the molecular mechanisms underlying how vitamins are synthesized, transported, and regulated in plants. We also stress the exploration of variation in vitamins by the use of forward genetic approaches, such as quantitative trait locus mapping and genome-wide association studies. Overall, we conclude that exploring the diversity of vitamins could provide new insights into plant metabolism and crop breeding. 相似文献
53.
Sinem Helvacıoğlu Mohammad Charehsaz Etil Güzelmeriç Mehmet Ali Oçkun İrem Ayran Hasan Kırmızıbekmez Yüksel Kan Ahmet Aydın Erdem Yeşilada 《化学与生物多样性》2021,18(10):e2000936
The antioxidant and mutagenic/antimutagenic activities of the fixed oils from Nigella sativa (NSO) and Nigella damascena (NDO) seeds, obtained by cold press-extraction from the cultivar samples, were comparatively investigated for the first time. The antimutagenicity test was carried out using classical and modified Ames tests. The fatty acid composition of the fixed oils was characterized by gas chromatography–mass spectrometry (GC-MS) while the quantification of thymoquinone in the fixed oils was determined by UPC2. The main components of the NSO and NDO were found to be linoleic acid, oleic acid, and palmitic acid. The results of the Ames test confirmed the safety of NSO and NDO from the viewpoint of mutagenicity. The results of the three antioxidant test methods were correlated with each other, indicating NDO as having a superior antioxidant activity, when compared to the NSO. Both NSO and NDO exhibited a significant protective effect against the mutagenicity induced by aflatoxin B1 in Salmonella typhimurium TA98 and TA100 strains. When microsomal metabolism was terminated after metabolic activation of the mycotoxin, a significant increase in antimutagenic activity was observed, suggesting that the degradation of aflatoxin B1 epoxides by these oils may be a possible antimutagenic mechanism. It is worthy to note that this is the first study to assess the mutagenicity of NSO and NDO according to the OECD 471 guideline and to investigate antimutagenicity of NDO in comparison to NSO against aflatoxin. 相似文献
54.
Muhammad Arslan Khan Hasan Riaz Muhammad Raheel Qaiser Shakeel Ummara Waheed Nadeem Ahmed Muhammad Bashair Waqas Ashraf Hafiz Tassawar Abbas Maria Siddique Maria Khan Ambreen Naz Musarrat Shaheen Asif Mahmood Arif Habib Ali Muhammad Nasir Mohammad Javed Ansari Hamed A. Ghramh Khalid Ali Khan 《Saudi Journal of Biological Sciences》2021,28(1):1-9
Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions. 相似文献
55.
I. Hasan L. Keilig S. Reimann F. Heinemann 《Computer methods in biomechanics and biomedical engineering》2013,16(12):1113-1116
It is always recommended to use more implants for supporting a prosthesis in the immediate loading condition than in the classical two-stage treatment procedure. By means of the finite element (FE) method, the influence of the number of implants used in immediately loaded fixed partial prosthesis (FPP) on the load distribution was investigated, considering the abutment geometry. Two 3D FE models were studied employing four implants to support a FPP in the premaxilla. One model was designed with straight abutments and the other with 20°-angled abutments. The results concerning implant displacements, stresses and strains were compared with those of two implant-supported FPPs, obtained in a previous study. A noticeable reduction in the determined biomechanical bone loading was observed with the use of more implants in supporting an immediately loaded prosthesis. This study confirms that the use of additional numbers of implants in an immediately loaded prosthesis is highly recommended. 相似文献
56.
Hasan Demirci Leyi Wang Frank V. Murphy IV Eileen L. Murphy Jennifer F. Carr Scott C. Blanchard Gerwald Jogl Albert E. Dahlberg Steven T. Gregory 《RNA (New York, N.Y.)》2013,19(12):1791-1801
The ribosome decodes mRNA by monitoring the geometry of codon–anticodon base-pairing using a set of universally conserved 16S rRNA nucleotides within the conformationally dynamic decoding site. By applying single-molecule FRET and X-ray crystallography, we have determined that conditional-lethal, streptomycin-dependence mutations in ribosomal protein S12 interfere with tRNA selection by allowing conformational distortions of the decoding site that impair GTPase activation of EF-Tu during the tRNA selection process. Distortions in the decoding site are reversed by streptomycin or by a second-site suppressor mutation in 16S rRNA. These observations encourage a refinement of the current model for decoding, wherein ribosomal protein S12 and the decoding site collaborate to optimize codon recognition and substrate discrimination during the early stages of the tRNA selection process. 相似文献
57.
Suitability indices and habitat suitability index model of Caspian kutum (Rutilus frisii kutum) in the southern Caspian Sea 总被引:1,自引:0,他引:1
Ali Haghi Vayghan Hadi Poorbagher Hamid Taheri Shahraiyni Hasan Fazli Hasan Nasrollahzadeh Saravi 《Aquatic Ecology》2013,47(4):441-451
The relationship between species and habitat is important in ecosystem-based fisheries management. Habitat suitability index (HSI) modeling is a valuable tool in ecology and can be used to describe the relationship between fish abundance and ecological variables in order to estimate the suitability of specific habitats. In the present study, an HSI model was applied to determine suitable habitats for the Caspian kutum (Rutilus frisii kutum), an important commercial species in the southern Caspian Sea. An arithmetic mean model (AMM) was found to be the most appropriate model for describing the relationship between two of the environmental variables investigated (depth and benthos biomass). However, a geometric mean model explained the evident relationship when all four environmental variables were used (depth, benthos biomass, photosynthetically active radiation and sea surface temperature). The areas with an HSI > 0.5 had over 85 % of the total catch indicating the reliability of the prediction of the Caspian kutum habitat using the AMM. The present study showed that depth and substrate structure are the most important environmental variables for the Caspian kutum to select its habitats, and between remotely sensed data, chlorophyll a, photosynthetically active radiation and sea surface temperature are the most critical parameters for near real-time prediction of the Caspian kutum habitat. 相似文献
58.
Yan?Pu Trevor?Treasure Ronalds?Gonzalez Richard?A.?VendittiEmail author Hasan?Jameel 《Bioenergy Research》2013,6(3):1094-1103
Autohydrolysis is a hot water pretreatment to extract soluble components from wood that can be used prior to converting the woody residuals into paper, wood products, fuel, or other goods. In this study, mixed softwood chips were autohydrolyzed in hot water at 150, 160, 170, and 180 °C for 1 and 2 h residence times. The objective was to understand the tradeoff between the extraction of fermentable sugar and the residual solid total energy of combustion quantitatively. This process strategy will be referred to as “value prior to combustion”. High-performance liquid chromatography was used to determine chemical compositions (sugars and byproducts such as acetic acid, furfural, and hydroxymethylfurfural) of the extracted liquid and residuals; a bomb calorimeter was used to measure the heating value of original wood and solid residue. As the autohydrolysis temperature increased, material balances of the system indicated higher volatile byproducts loss. More hemicelluloses were solubilized by the hot water extraction process at higher temperatures and longer residence times, and a greater degree of sugar degradation was also observed. The maximum sugar yield was determined to occur at conditions of 170 °C for 2 h, during which 13 g of sugar was recovered from the extract out of 100 g of oven-dried wood. The heating value of the solid residues after extraction was greater than the original wood. The total energy content of the solid residual after extraction ranged from 85 to 98 % of the original energy content of the feed with higher temperatures reducing the total energy content. 相似文献
59.
60.
Insect flight is regulated by various sensory inputs and neuromodulatory circuits which function in synchrony to control and fine-tune the final behavioral outcome. The cellular and molecular bases of flight neuromodulatory circuits are not well defined. In Drosophila melanogaster, it is known that neuronal IP3 receptor mediated Ca2+ signaling and store-operated Ca2+ entry (SOCE) are required for air-puff stimulated adult flight. However, G-protein coupled receptors (GPCRs) that activate intracellular Ca2+ signaling in the context of flight are unknown in Drosophila. We performed a genetic RNAi screen to identify GPCRs that regulate flight by activating the IP3 receptor. Among the 108 GPCRs screened, we discovered 5 IP3/Ca2+ linked GPCRs that are necessary for maintenance of air-puff stimulated flight. Analysis of their temporal requirement established that while some GPCRs are required only during flight circuit development, others are required both in pupal development as well as during adult flight. Interestingly, our study identified the Pigment Dispersing Factor Receptor (PdfR) as a regulator of flight circuit development and as a modulator of acute flight. From the analysis of PdfR expressing neurons relevant for flight and its well-defined roles in other behavioral paradigms, we propose that PdfR signaling functions systemically to integrate multiple sensory inputs and modulate downstream motor behavior. 相似文献