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关键词： 基础生物化学   混合学习   线下学习   教学效果分析  

摘要： 采用对比实验将混合学习和单纯线下学习在基础生物化学中的效果进行了量化分析。结果显示,所有班级的混合学习组相比线下学习组的测试成绩均有所提高;其中,混合学习组B1a-B4a平均成绩在63.7~74.6之间,线下学习组C1a-C4a平均成绩在55.9~58.3之间,组间差异显著(P<0.05)。混合学习组对理解型和应用型试题的得分明显高于线下学习组;混合学习组对自身学习效果的主观评价也更高。这些研究结果为基础生物化学教学方式方法改革提供了理论参考。

关键词： 气相色谱—串联质谱法   食品分析   应用发展  

摘要： 气相色谱—串联质谱法不仅有气相色谱法的高分离性能,而且能准确鉴定各种化合物的结构,广泛用于石化、环境、中药、食品和农药残留等领域,尤其是在易衍生或挥发性化合物的分析中。因此,本文首先概述GC-MS的原理,然后分析该技术在食品和中药中的应用。

关键词： Biochemical   Gene expression   Plant-Pest interaction   Solanaceae   ACTIVATED PROTEIN-KINASE   SOLANUM-LYCOPERSICON L.   SALICYLIC-ACID   LEPIDOPTERA-GELECHIIDAE   PLANT DEFENSE   AMINO-ACIDS   HELICOVERPA-ARMIGERA   DISEASE RESISTANCE   BRASSICA-OLERACEA   COTTON BOLLWORM  

摘要： Tomato is more prone to Tuta absoluta invasion and damages as compared to other host plants but the mechanism behind this preference has not been elucidated. Here, two contrasting host preference plants, tomato and eggplant, were used to investigate biochemical and transcriptomic modifications induced by T. absoluta infestation. Biochemical analysis at 0-72 h post T. absoluta infestation revealed significantly reduced concentrations of amino acid, fructose, sucrose, jasmonic acid, salicylic acid, and total phenols in tomato compared to eggplant, mainly at 48 h post T. absoluta infestation. Transcriptome analysis showed higher transcript changes in infested eggplant than tomato. Signaling genes had significant contributions to mediate plant immunity against T. absoluta, specifically genes associated with salicylic acid in eggplant. Genes from PR1b1, NPR1, NPR3, MAPKs, and ANP1 families play important roles to mitigate T. absoluta infestation. Our results will facilitate the development of control strategies against T. absoluta for sustainable tomato production.

关键词： Environment   general   Environmental Chemistry   Ecotoxicology   Environmental Health   Atmospheric Protection/Air Quality Control/Air Pollution   Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution  

摘要： A correction to this paper has been published: https://***/10.1007/s11356-021-14285-8

关键词： Hsp110   Hsp70   Molecular chaperones   Protein folding   Protein homeostasis   NUCLEOTIDE EXCHANGE FACTORS   YEAST HSP110   HSP70 CHAPERONES   SUBSTRATE-BINDING   CRYSTAL-STRUCTURE   CELL-GROWTH   SSE1   FAMILY   PROTEINS   DISTINCT  

摘要： Hsp110s are unique and essential molecular chaperones in the eukaryotic cytosol. They play important roles in maintaining cellular protein homeostasis. Candida albicans is the most prevalent yeast opportunistic pathogen that causes fungal infections in humans. As the only Hsp110 in Candida albicans, Msi3 is essential for the growth and infection of Candida albicans. In this study, we have expressed and purified Msi3 in nucleotide-free state and carried out biochemical analyses. Sse1 is the major Hsp110 in budding yeast S. cerevisiae and the best characterized Hsp110. Msi3 can substitute Sse1 in complementing the temperature-sensitive phenotype of S. cerevisiae carrying a deletion of SSE1 gene although Msi3 shares only 63.4% sequence identity with Sse1. Consistent with this functional similarity, the purified Msi3 protein shares many similar biochemical activities with Sse1 including binding ATP with high affinity, changing conformation upon ATP binding, stimulating the nucleotide-exchange for Hsp70, preventing protein aggregation, and assisting Hsp70 in refolding denatured luciferase. These biochemical characterizations suggested that Msi3 can be used as a model for studying the molecular mechanisms of Hsp110s.

关键词： X-ray   CT-Scan   Biochemical study   Hematology study   Radiation dose   Radiographers  

摘要： The effects of annual exposure radiation doses on the some biochemical {alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), and uric acid (UAC)} and hematological parameters (white blood cells (WBCs), red blood cells (RBCs), and plate count (PLT)) of radiographer's blood samples from some Erbil Hospitals have been investigated. Biochemical and hematological tests have been done for both of the radiographers performing X-ray and CT-scans (cases) and the unexposed operators (control). Results of the biochemical and hematological tests proved a significant association between the levels of radiation exposure (effective dose) concerning radiographers of X-ray and CT-scan and the rate of radiation leakage (P < 0.01). Maximum and minimum average leakage radiation doses for the radiographers were found in the Hawler Education hospital (HEH) (3.84 +/- 0.03 mSv/year) and CMC hospital (CMCH) (0.28 +/- 0.02 mSv/year), respectively. High and low biochemical and hematological effects were found in the HEH and CMCH, respectively. Most of the radiographers (regarding the time of exposure) at risk of exposure to X-ray and CT-scan radiation exposure and the levels are exceeding the standard guidelines. Therefore, immediate radiation protection measures need to be initiated to the employees (technicians, attendants, and maintenance staff) at the X-ray and CT-scan departments.

关键词： Metal   Metabolomics   Mytilidae   Deep-sea   Antioxidant enzymes   Physiological stress   Environment monitor   Toxicology   DIFFERENT PURIFICATION PROCEDURES   ALKALINE-PHOSPHATASE ACTIVITY   CENTRAL-NERVOUS-SYSTEM   HYDROTHERMAL VENT   MYTILUS-GALLOPROVINCIALIS   OXIDATIVE STRESS   ANTIOXIDANT RESPONSES   LIPID-PEROXIDATION   IMMUNE-RESPONSES   METAL POLLUTION  

摘要： Greater interest in commercial deep-sea mining has been accompanied by mounting environmental concerns, including metal contamination resulting from mining activities. However, little is known about the toxic effects of metal exposure on deep-sea life. Given its ability to accumulate metals from the surrounding environment, its wide distribution at both vents and seeps, and its high abundance, the deep-sea mussel Bathymodiolus platifrons could serve as an ideal model to investigate the toxicological responses of deep-sea organisms to metal exposure. Here, we evaluated metal accumulation, traditional metal-related biomarkers, namely acid phosphatase (ACP), alkaline phosphatase (AKP), superoxide dismutase, catalase, reduced glutathione, metallothioneins, and malondialdehyde, as well as metabolic profiles in the gills of B. platifrons after a 7-day exposure to copper (100 mu g/L), cadmium (500 mu g/L), or copper-plus-cadmium treatments (100 mu g/L Cu and 500 mu g/L Cd). Metal exposure concentrations selected in this study can be found in deep-sea hydrothermal environments. Metal exposure resulted in significant metal accumulation in the gills of the mussel, indicating that B. platifrons has promise for use as an indicator of deep-sea metal pollution levels. Traditional biomarkers (AKP, ACP, and measured antioxidants) revealed cellular injury and oxidative stress in mussels following metal exposure. Metabolic responses in the three treatment groups indicated that metal exposure perturbed osmoregulation, energy metabolism, and nucleotide metabolism in mussels, in a response marked by differentially altered levels of amino acids, hypotaurine, betaine, succinate, glucose 6-phosphate, fructose 6-phosphate, guanosine, guanosine 5 '-monophosphate, and inosine. Nevertheless, several uniquely altered metabolites were found in each treatment exposure group, suggesting dissimilar modes of toxicity between the two metal types. In the Cd-exposed group, the monosaccharide D-allose,

关键词： Fruit ripening   Mango fruit puree   Rheology   FTIR spectroscopy   Particle size  

摘要： This study proposed to investigate the impact of ripening on the physical properties of mango purees. An extensive study of the particle size and rheological properties of mango purees and their dispersed phase was performed using particle size measurements, small deformation rheology, and an innovative technology combining simultaneous rheometry and in situ FTIR spectroscopy. The results revealed a sharp decrease in the solid-like behavior of mango purees, as well as in the energy of cohesion of their dispersed phase during the first 10 days of ripening, leading to a weakening of their gel-structure. The size of suspended insoluble solids in the purees continued to decrease until 15 days of ripening. According to the spectral fingerprints, it was possible to identify some changes in the purees' sugar content occurring upon the physical changes during ripening. The highest sucrose and lowest fructose contents were observed in purees obtained during the first 10 days of ripening, in comparison with the following days. Based on the twin physical and spectral fingerprints, purees obtained from the early days of ripening (<10 days) could be distinguished from other purees.

关键词： Silver nanoparticles   Biosorption   Metal toxicity   Bioremediation   Oreochromis niloticus   CARP CYPRINUS-CARPIO   TITANIUM-DIOXIDE NANOPARTICLES   OXIDATIVE STRESS   PHOSPHATASE-ACTIVITY   NILE TILAPIA   TOXICITY   WATER   RESPONSES   METAL   ASSAY  

摘要： Silver nanoparticles (Ag NPs) have wide medical and industrial applications; therefore, their release into aquatic environments is a problematic issue. The present study aims to evaluate the removal efficiency of Ag NPs from water using orange peel (OP) and banana peel (BP) to moderate their toxicity on Oreochromis niloticus. Fish were divided into 4 groups: control group (dechlorinated tap water), Ag NPs (4 mg/L) exposed group, Ag NPs (4 mg/L) + OP (40 mg/L) group, and Ag NPs (4 mg/L) + BP (40 mg/L) group for 24 h, 48 h, and 96 h. The adsorptive ability of both peels was confirmed by scanning electron microscope and energy-dispersive X-ray spectroscopy after the exposure processes. The biochemical results revealed a gradual elevation in plasma glucose, total proteins, globulin, liver enzymes (AST, ALT, and ALP), creatinine, and uric acid after Ag NPs exposure, while albumin and total lipid concentrations were significantly decreased. The recorded antioxidant biomarkers in gills, and liver tissues after Ag NPs exposure showed severe oxidative damages (maximally after 96 h) as indicated by marked elevations in thiobarbituric acid reactive substances, glutathione peroxidase, catalase, and superoxide dismutase values, and decreased glutathione reduced content. All studied parameters restored more or less to that of control groups after OP and BP water treatment. The adsorbent abilities of both peels could reduce Ag NPs bioavailability and moderate their toxicological impacts.