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关键词： 翻转课堂教学   思维导图   教学效果  

摘要： 通过“课前观看视频或者微课或者资料等”翻转课堂模式,完成知识的传递及课上交流讨论的辅导探究,来实现学生的知识内化,推动传统课堂教学的革新和完善。本文结合作者以往的教学经验,提出基于思维导图的方式进一步提升翻转课堂的教学效果,为增强高校基础专业课的教学效果提供一定参考案例。

关键词： Ammonium   n-caproate   Lactate   Chain elongation   Food waste   HEXANOIC ACID PRODUCTION   CLOSTRIDIUM-KLUYVERI   MEGASPHAERA-ELSDENII   ANAEROBIC-DIGESTION   INHIBITION   NITROGEN   PH   NITRIFICATION   FERMENTATION   TEMPERATURE  

摘要： Ammonium accumulation is inevitable during the fermentation of food waste (FW), challenging the application of chain elongation process upgrading FW into the high-value biochemical n-caproate, which is a medium chain carboxylate. This study is the first to investigate ammonium inhibition of lactate-driven chain elongation process. The short-term exposure of a Clostridium IV-dominated chain elongating reactor microbiome at an ammonium concentration of 1-4 g L-1 linearly decreased n-caproate production by 25-80%. High levels of ammonium (>= 5 g L-1) could cause failure of chain elongation, shifting the product from n-caproate to propionate. The involved mechanisms revealed that ammonium reshaped the microbial community from Clostridium IV domination to Clostridium IV and Propionibacterium co-domination (based on 16S rRNA sequencing) and reduced the activities of key enzymes involved in the reversed beta-oxidization pathway. We propose an effective strategy from our study, which is the first one to do in our knowledge, to upgrade raw MT without dilution to n-caproate: lowering the ammonium accumulation to 1.0 g L-1 at the setup phase for adaptation and prolonging the hydraulic retention time (10 days) during the operation phase for the colonization of chain-elongation bacteria. These findings lay a foundation for the implementation of the LCE process on FW, providing an alternative way to alleviate the global MW crisis. (C) 2021 Published by Elsevier Ltd.

关键词： Scalding duration   Brine-type cheese   Chemical composition   Texture   Microstructure   VOLATILE COMPOUNDS   MILK PASTEURIZATION   FULL-FAT   TEMPERATURE   PROTEOLYSIS   ACID   STARTER   CHYMOSIN   MALATYA  

摘要： The effects of curd scalding duration on chemical, biochemical, color, textural, microstructural and sensorial characteristics of a brine-type cheese were examined. The cheeses that were characterized by the scalding of curd in hot whey (60 degrees C) and brining in whey were manufactured from raw cows' milk and the curds were scalded for 10, 20 or 30 min. Regardless of cheese ripening time, increased scalding duration resulted in decreased moisture, titratable acidity, lactic acid, ethanol, whitening index and h degrees values. The images obtained by scanning electron microscopy of the cheeses were clearly different each other. At the end of ripening, cheeses from curds scalded for up to 20 min had the highest water-soluble nitrogen, 2-phenylethyl acetate, acetic acid, chewiness, gumminess and hardness levels, and overall acceptability scores. In conclusion, scalding of curd in whey up to 20 min at 60 degrees C gave satisfactory results in terms of quality parameters of the present cheeses.

关键词： Antioxidant capacity   Glomus mosseae   Leaf elements   Plant growth-promoting rhizobacteria   Polyunsaturated fatty acid   Vermicompost   ARBUSCULAR MYCORRHIZAL FUNGI   PROMOTING RHIZOBACTERIA PGPR   PLANT-GROWTH   ANTIOXIDANT ACTIVITY   PHENOLIC-COMPOUNDS   L.   YIELD   VERMICOMPOST   PHOSPHORUS   QUALITY  

摘要： Appropriate soil conditions as a cultural practice are the basis of medicinal plant production. The experiment was carried out to investigate the effect of NPK, vermicompost (VC), Pseudomonas fluorescens (PF), Azotobacter chroococcum (AC), Azospirillum brasilense (AB), Glomus mosseae (AMF) on plant weight, antioxidant capacity and fatty acid (FA) profile of seed oil, and leaf nutrients of black cumin (Nigella sativa Linn) in 2018 and 2019. The results showed that dry weight in plants treated with VC (24.9 g and 28.8 g) or in AMF-inoculated plants (23.4 g and 27.8 g) was significantly higher compared with other treatments in 2018 and 2019, respectively. The highest (1.34 mg gallic acid (GA) g-1 oil) total phenolic content (TPC) and DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activity (86.8 %) was observed in plants treated with VC, and followed by AMF. The main fatty acid component was linoleic acid (51.92?55.46 %), followed by oleic acid (22.6?24.5 %) and palmitic acid (13.24?16.27 %). The saturated fatty acid (SFA) under NPK application (23.39 % and 24.21 % in 2018 and 2019) was higher than other experimental treatments. Monounsaturated fatty acid (MUFA) concentration in plants inoculated with AMF (25.15 % and 25.41 % in 2018 and 2019, respectively) or supplied with AB and PF was greater. The seed oil of black cumin contained the significant level of polyunsaturated fatty acid (PUFA), which its highest content was obtained at in plants treated with VC as 55.74 % and 55.79 % in 2018 and 2019, respectively. Sustainable agricultural practices are required to increase ecofriendly performance, by using soil micro-organisms, conserving the natural resource base for improved medicinal plant cultivation.

关键词： Zirconia   Laser patterning   Surface functionalization   Peptides   Osteointegration   LOW-TEMPERATURE DEGRADATION   ALUMINA TOUGHENED ZIRCONIA   OSTEOGENIC DIFFERENTIATION   SURFACE-TOPOGRAPHY   TITANIUM SURFACE   CELL ALIGNMENT   GRAIN-SIZE   IN-VITRO   IMPLANTS   TISSUE  

摘要： A dual approach employing peptidic biofunctionalization and laser micro-patterns on dental zirconia was explored, with the aim of providing a flexible tool to improve tissue integration of restorations. Direct laser interference patterning with a femtosecond Ti:Sapphire laser was employed, and two periodic grooved patterns were produced with a periodicity of 3 and 10 mu m. A platform containing the cell-adhesive RGD and the osteogenic DWIVA peptides was used to functionalize the grooved surfaces. Topography and surface damage were characterized by confocal laser scanning (CLSM), scanning electron and scanning transmission electron microscopy techniques. The surface patterns exhibited a high homogeneity and subsurface damage was found in the form of nano-cracks and nano-pores, at the bottom of the valleys. Accelerated tests in water steam were carried out to assess hydrothermal degradation resistance, which slightly decreased after the laser treatment. Interestingly, the detrimental effects of the laser modification were reverted by a post-laser thermal treatment. The attachment of the molecule was verified trough fluorescence CLSM and X-ray photoelectron spectroscopy. Finally, the biological properties of the surfaces were studied in human mesenchymal stem cells. Cell adhesion, morphology, migration and differentiation were investigated. Cells on grooved surfaces displayed an elongated morphology and aligned along the patterns. On these surfaces, migration was greatly enhanced along the grooves, but also highly restricted in the perpendicular direction as compared to flat specimens. After biofunctionalization, cell number and cell area increased and well-developed cell cytoskeletons were observed. However, no effects on cell migration were found for the peptidic platform. Although some osteogenic potential was found in specimens grooved with a periodicity of 10 mu m, the largest effects were observed from the biomolecule, which favored upregulation of several genes

关键词： Photonic crystal fiber (PCF)   Biosensor   Wavelength sensitivity (WS)   Amplitude sensitivity (AS)   Figure of merits (FOM)   PHOTONIC CRYSTAL FIBER   MICROSTRUCTURED-OPTICAL-FIBER   REFRACTIVE-INDEX SENSOR   BIREFRINGENT   LIQUID   BIOSENSOR  

摘要： We present a simple, unique, and highly sensitive surface plasmon resonance (SPR)-based photonic crystal fiber (PCF) biosensor. Besides having very high sensitivity, our proposed sensor is also fabrication friendly. The finite element method (FEM) of COMSOL 5.3a was utilized to devise the sensor's structure and analyze the impact of changing geometric parameters on this biosensor's overall performance. Gold (Au) or AZO (aluminum-doped zinc oxide) can be utilized to create excitation between the two modes (core and plasmonic). We have tried to vary different parameters of the PCF, and we observed in simulation results a very high amplitude sensitivity (AS) of 4358.09 RIU-1, maximum wavelength sensitivity (WS) of 21,000 nm/RIU (refractive index unit), a high figure of merits (FOM) of 729 with a sensor resolution of 4.76 x 10(-6) RIU and 2.29 x 10(-6) RIU for wavelength, and amplitude respectively when gold was utilized as the plasmonic material. Replacing gold by AZO resulted in the corresponding values of 3908 RIU-1, 1700 nm/RIU, 792, 5.88 x 10(-5) RIU, and 2.56 x 10(-6) RIU. Analyte refractive index (RI) ranges between 1.33-1.42 for gold and 1.31-1.39 for AZO. We believe the high performance of our proposed SPR based PCF biosensor in terms of sensitivity will bring a promising advancement in the field of unknown analyte detection and biological organic chemicals.

关键词： monocot chimeric jacalin   lectin   OsJAC1   dirigent domain   melting point   carbohydrate-binding   GLUCOSIDASE-AGGREGATING FACTOR   DIRIGENT PROTEIN   PLANT-LECTINS   CRYSTAL-STRUCTURE   BINDING   DOMAIN   OVEREXPRESSION   RECOGNITION   SPECIFICITY   HOMOLOG  

摘要： The monocot chimeric jacalin OsJAC1 from Oryza sativa consists of a dirigent and a jacalin-related lectin domain. The corresponding gene is expressed in response to different abiotic and biotic stimuli. However, there is a lack of knowledge about the basic function of the individual domains and their contribution to the physiological role of the entire protein. In this study, we have established a heterologous expression in Escherichia coli with high yields for the full-length protein OsJAC1 as well as its individual domains. Our findings showed that the secondary structure of both domains is dominated by beta-strand elements. Under reducing conditions, the native protein displayed clearly visible transition points of thermal unfolding at 59 and 85 degrees C, which could be attributed to the lectin and the dirigent domain, respectively. Our study identified a single carbohydrate-binding site for each domain with different specificities towards mannose and glucose (jacalin domain), and galactose moieties (dirigent domain), respectively. The recognition of different carbohydrates might explain the ability of OsJAC1 to respond to different abiotic and biotic factors. This is the first report of specific carbohydrate-binding activity of a DIR domain, shedding new light on its function in the context of this monocot chimeric jacalin.

关键词： Almond   In vitro   Micrografting   Micropropagation   Rootstock   ANTIOXIDANT SYSTEM   SCION   STRESS   GROWTH   RESPONSES   NACL   TOLERANCE   PROLINE   L.  

摘要： Grafted fruit trees are made up of two parts, the scion and the rootstock. The rootstocks affect the growth and physiological and biochemical treats of scion. The use of grafting technique in vitro produces healthy plants and allows careful study of rootstock and scion interactions. The objective of this research was to achieve a successful protocol for micrografting of the late-flowering Sahand cultivar on two wild almond rootstocks (Badam Kohi and Arjan) and also to determine the best rootstock for mentioned cultivar. In this regard, a factorial experiment was conducted to investigate the effect of rootstock type, culture medium (MD1 = MS, MD2 = MS +0.49 mu M IBA + 2.2 mu M BA, MD3 = MS + 2.46 mu M IBA + 0.44 mu M BA) and supporting system (paper bridge and perlite) on micrografting success of 'Sahand' scion. The results showed that in micrograft combination of 'Sahand'/Badam kohi, the highest grafting success (100%) and scion length (27.8 mm) were achieved on the MD2 medium with perlite. The Arjan rootstock increased electrolyte leakage and decreased total chlorophyll of the scion in compare to Badam Kohi rootstock. In the grafted combinations, the highest amount of superoxide dismutase, peroxidase and catalase activities were recorded in 'Sahand' on the Badam Kohi rootstock which were significantly higher than in the same scion on Arjan rootstock. It can be concluded that Badam Kohi is more suitable than Arjan as a rootstock for Sahand cultivar. Key message In vitro wedge micrografting was successfully established for Sahand cultivar on wild almond rootstocks using IBA and BA combinations in culture media. Badam Kohi rootstock supported 'Sahand' scion by induced more antioxidant enzymes than Arjan rootstock.

关键词： Coastal waters   Environmental toxicology   Risk assessment   Warfarin   Dexamethasone   Imidazole   Invertebrates   Gene expression   Antioxidant enzymes   PERSONAL CARE PRODUCTS   PREGNANE-X-RECEPTOR   EXPRESSION IN-VIVO   GENE-EXPRESSION   WASTE-WATER   NUCLEAR RECEPTORS   CHINA IMPACTS   IMIDAZOLE 2-HYDROXYBENZOATE   ANTICOAGULANT RODENTICIDES   SYNTHETIC GLUCOCORTICOIDS  

摘要： Pharmaceuticals represent a group of emerging contaminants. The short-term effect (3 and 7 days) of warfarin (1 and 10 mg L-1), dexamethasone (0.392 and 3.92 mg L-1) and imidazole (0.013 and 0.13 mg L-1) exposure was evaluated on mussels (Mytilus galloprovincialis). Total antioxidant status, glutathione reductase, glutathione peroxidase (GPx) and superoxide dismutase enzyme activities, and the expression of genes involved in the xenobiotic response (ATP binding cassette subfamily B member 1 (abcb1) and several nuclear receptor family J (nr1j) isoforms), were evaluated. All nr1j isoforms are suggested to be the xenobiotic receptor orthologs of the NR1I family. All drugs increased GPx activity and altered the expression of particular nr1j isoforms. Dexamethasone exposure also decreased abcb1 expression. These findings raised some concerns regarding the release of these pharmaceuticals into the aquatic environment. Thus, further studies might be needed to perform an accurate environmental risk assessment of these 3 poorly studied drugs.

关键词： Klenow fragment   DNA exonuclease   DNA endonuclease   Manganese   Pre-steady-state kinetics   Deinococcus radiodurans   STRAND DISPLACEMENT SYNTHESIS   ESCHERICHIA-COLI   TARGETED MUTAGENESIS   EXONUCLEASE ACTIVITY   FLAP ENDONUCLEASE-1   HYDROGEN-PEROXIDE   REPLICATION   DAMAGE   REPAIR   MUTANTS  

摘要： Deinococcus radiodurans survives extraordinary doses of ionizing radiation and desiccation that cause numerous DNA strand breaks. D. radiodurans DNA polymerase A (DrPolA) is essential for reassembling the shattered genome, while its biochemical property has not been fully demonstrated. In this study, we systematically examined the enzymatic activities of DrPolA and characterized its unique features. DrPolA contains an N-terminal nuclease domain (DrPolA-NTD) and a C-terminal Klenow fragment (KlenDr). Compared with the Klenow fragment of E. coli Pol I, KlenDr shows higher fidelity despite the lacking of 5 '-3 ' exonuclease proofreading activity and prefers double-strand DNA rather than Primer-Template substrates. Apart from the well-annotated 5 '-3 ' exonuclease and flap endonuclease activities, DrPolA-NTD displays approximately 140-fold higher gap endonuclease activity than its homolog in E. coli and Human FEN1. Its 5 '-3 ' exonuclease activity on ssDNA, gap endonuclease, and Holliday junction cleavage activities are greatly enhanced by Mn2+. The DrPolA-NTD deficient strain shows increased sensitivity to UV and gamma-ray radiation. Collectively, our results reveal distinct biochemical characteristics of DrPolA during DNA degradation and re-synthesis, which provide new insight into the outstanding DNA repair capacity of D. radiodurans. (C) 2021 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.