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关键词： Zoology   Veterinary Medicine/Veterinary Science  

关键词： Bacillus subtilis   Biochar   Defense mechanism   Gene expression   Induced resistance   INDUCED SYSTEMIC RESISTANCE   FUSARIUM-OXYSPORUM   SALICYLIC-ACID   JASMONIC ACID   LIPID-PEROXIDATION   COMPOST AMENDMENTS   GROWTH   SOIL   INDUCTION   BIOCONTROL  

摘要： This study was aimed to elucidate the biochar induced resistance pathways in association with beneficial plant growth promoting rhizobacteria (PGPR) in the tomato (Solanum lycopersicum) - Alternaria solani pathosystem. To examine the impact of biochar on plant defense mechanisms at the molecular level, tomato plants were grown in two different biochars (wood and green waste biochar; 3 and 6% application level of each) both with and without Bacillus subtilis, (PGPR). Although, the reduction in disease index and disease incidence was significant in wood biochar amended soil but the resistant plant response against early blight was only recorded in the 6% green waste biochar amended treatment. Biochar application has induced the expression of defense associated genes including jasmonic acid related PI2, TomloxD, salicylic acid related PR1a, PR2 and ethylene responsive Pti4. Green waste biochar (6%) was more efficient in eliciting the expression level of TomloxD, PI2, PR1a and PR2 in tomatoes challenged by A. solani, while PGPR inoculation has enhanced the PR2 expression levels in comparison to tomatoes grown in wood biochar amended soil substrate. Moreover, phenolics, catalase and peroxidase production levels of plants grown in green waste biochar alone as well as in the presence of B. subtilis, contributed significantly in moderating infection induced damages. In conclusion, tomatoes response to invading A. solani was dependent on the type of biochar, while protection against early blight was better at higher application rate of biochar i.e. 6%. Different biochar types also differ with their ability to elicit the defense gene expression/signaling pathways. Our study revealed that biochar and PGPR induced protection against early blight of tomatoes involves both induced systemic resistance (ISR) and systemic acquired resistance (SAR) mechanisms.

关键词： Anisohydric   isohydric behavior   Antioxidant   Drought resistance   Endogenous hormone   Leaf morphology   Photosynthetic response   Plantation species   CLIMATE-CHANGE IMPACTS   NORWAY SPRUCE   PHOTOSYNTHETIC RESPONSE   HYDRAULIC CONDUCTANCE   STRESS RESPONSES   ABSCISIC-ACID   LEAF SIZE   GROWTH   WATER   MORTALITY  

摘要： The frequency and severity of drought are expected to increase due to climate change; therefore, selection of tree species for afforestation should consider drought resistance of the species for maximum survival and conservation of natural habitats. In this study, three soil moisture regimes: control (100% precipitation), mild drought (40% reduction in precipitation), and severe drought (80% reduction in precipitation) were applied to six gymnosperm and five angiosperm species for two consecutive years. We quantified the drought resistance index based on the root collar diameter and assessed the correlation between species drought resistance and other morphological, physiological, and biochemical traits by regression analysis. The prolonged drought stress altered the morphological, physiological, and biochemical traits, but the responses were species-specific. The species with high drought resistance had high leaf mass per area (LMA), photosynthetic rate (Pn), and midday leaf water potential (psi MD), and low carbon isotopic discrimination (513C), flavonoid and polyphenol content, superoxide dismutase and DPPH radical scavenging activity. The highly drought-resistant species had a relatively less decrease in leaf size, Pn, and predawn leaf water potential (psi PD), and less increase in 513C, abscisic acid and sucrose content, and LMA compared to the control. The interannual variation in drought resistance (delta Rd) was positively correlated with the species hydroscopic slope (isohydric and anisohydric). Korean pine was highly resistant, sawtooth oak, hinoki cypress, East Asian white birch, East Asian ash, and mono maple were highly susceptible, and Korean red pine, Japanese larch, Sargent cherry, needle fir, and black pine were moderate in drought resistance under long-term drought. These findings will help species selection for afforestation programs and es-tablishment of sustainable forests, especially of drought-tolerant species, under increased frequency and in

关键词： Time scale analysis   Characteristic times   Modeling-based design   Microscale-based technology   PROCESS INTENSIFICATION   METHODOLOGY   KINETICS  

摘要： Time-Scale Analysis and Characteristic Times are suggested as a novel and useful tool in the analysis of the performance of microscale-based reactors, unit operations, and plant flow-sheet diagrams embodying microscale-based chemical processes. Transport phenomena, reaction kinetics, and phase contacting in microstructured architecture can be easily represented by unique time constants, tau(i)[s]. These Characteristic Times are estimated from first principles and are controlled by a user to support a meaningful chemical process analysis and provide insight or suggestions for successful design choices. While the origin of Characteristic Times in microscale-based processes is rooted in fundamentals of molecular transport and reaction kinetics, the evolution of Characteristic Time definitions could be easily found in detailed mathematical models of microscale-based reaction processes and operations. The user defined scaling parameters contribute to the flexibility of Time Scale Analysis implementation. This work uses a microscale-based solid catalyzed reaction process to demonstrate the concept of Time Scale Analysis and systematically define Characteristic Times and their origin. Lastly, varying forms of Time Scale Analysis have been implemented to evaluate specific phenomena or aspects of processes but have yet to encompass the full unit operation or process within the analysis. Part I and Part II of this work develop a comprehensive Time Scale Analysis for unit operations and a (bio)chemical process flowsheet (Part II only). (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Biofloc system   Red tilapia   Bio-chemical enzymes   Carcass quality   Inland saline ground water   LITOPENAEUS-VANNAMEI BOONE   IMPROVED FARMED TILAPIA   PROXIMATE COMPOSITION   ENZYME-ACTIVITIES   IMMUNE-RESPONSE   POND WATER   TECHNOLOGY   ANTIOXIDANT   PERFORMANCE   AQUACULTURE  

摘要： Biofloc based aquaculture is important in waste recycling in intensive aquaculture and is a promising avenue for inland saline aquaculture. In the present study, growth, biochemical and carcass quality of red tilapia reared in inland saline waters of different salinities based on biofloc technology was estimated during 90 days culture period. Fifteen experimental tanks (500 L each) were filled with inland saline ground water to represent 5 biofloc treatments with variable salinities such as T1 (5 ppt), T2 (10 ppt), T3 (15 ppt), T4 (20 ppt) and control (0 ppt) in triplicates. Red tilapia fry with average body weight of 13.78 +/- 0.62 g were stocked at the rate of 150 no.m -3 in each biofloc unit. The units maintained at higher salinity (20 ppt) obtained significantly better (P < 0.05) growth performances in terms of percentage weight gain (329.89 +/- 13.41), specific growth rate (1.65 +/- 0.05), protein efficiency ratio (1.18 +/- 0.07) and feed conversion ratio (0.93 +/- 0.06). Biochemical properties such as serum glucose (118.49 +/- 3.73 mg dL-1), serum total protein (4.23 +/- 0.04 mg dL-1), total serum albumin (2.08 +/- 0.03 mg dL-1), and total serum globulin (2.16 +/- 0.04 mg dL-1) contents were the highest in T4 (20 ppt), whereas activities of enzymes, superoxide dismutase and catalase were the highest in control (0 ppt). Treatment T4 (20 ppt) had shown the highest survival rate (95.56 +/- 1.28), carcass quality like firmness (121.45 +/- 1.91), and whiteness (49.52 +/- 0.79) and in addition, overall sensory attributes were also the highest in T4 (20 ppt). Consequently, the findings of the current investigation have shown that growth efficiency, survival, biochemical indices and carcass quality of red tilapia had improved when reared in higher salinity using inland saline groundwater.

关键词： Heavy metals  

摘要： Macroalgal biosorption has shown promise for the removal of metal ions from wastewaters, whose presence can pose a threat to the aquatic environment. There is a wealth of literature published on macroalgal biosorption, the common thread being that the biosorbent material was collected from the field, under undefined conditions. These studies offer little insight into the impact of prior cultivation or biomass production practices upon the biosorbent material, its adsorptive physico-chemical properties and its subsequent capacity for metal removal. The present study sought to investigate the influence of changes in macroalgal cultivation, specifically nutrient regime, upon biomass properties and the resultant adsorption performance. The macroalga Cladophora parriaudii was cultivated under six different nutrient regimes; 2:1 and 12:1 N:P molar ratios, with nitrogen supplied either as ammonium (NH4+), nitrate (NO3−), or urea (CO(NH2)2). These nutrient regimes were designed to produce biomass of varying biochemical and cell surface profiles. After cultivation, the biomass was rinsed, dried, biochemically analysed and then used for the removal of four individual metals from solution. Metal removal varied considerably between treatments and across initial metal concentrations, with removal values of 46–85%, 9–80%, 8–71%, and 49–94% achieved for Al, Cu, Mn, and Pb, respectively, with initial metal concentrations varying between 0 and 150 mg L−1. The observed variation in metal removal can only be attributed to differences in biochemistry and cell surface properties of the biosorbent induced by nutrient regime, as all other variables were constant. This study demonstrates that prior cultivation conditions influence the biochemistry of a biosorbent material, namely macroalgae Cladophora parriaudii, which has an impact upon metal removal. This aspect should be given due consideration for future biosorption research and when reviewing already published literature. © 2021

关键词： 生化检验指标   糖尿病诊断   临床价值  

摘要： 目的:分析在临床诊断糖尿病患者时应用生物化学检验指标的作用.方法:选取我院2019年8月至2020年8月的糖尿病患者100例,按照随机数字表示法分为实验组(n=50)和常规组(n=50),两组分别开展生物化学检验、常规尿液检验,对临床检出率进行观察比较.结果:与常规组相比,实验组的临床总检出率明显提高(P<0.05).结论:在临床诊断糖尿病患者时,应用生物化学检验具有较高的临床检出率,值得推广使用.

关键词： Substrate biodegradability assessment   Biochemical sulfide potential assay   Sulfidogenesis   Inoculum-to-substrate ratio   Waste activated sludge   WASTE ACTIVATED-SLUDGE   EXTRACELLULAR POLYMERIC SUBSTANCES   NITROUS-ACID PRETREATMENT   METHANE PRODUCTION   CO-DIGESTION   SULFATE REDUCTION   SUBSTRATE RATIO   WATER TREATMENT   SEWAGE-SLUDGE   FOOD WASTE  

摘要： The anaerobic biodegradability assessment (biodegradation extent and kinetics) of organic wastes is critical for optimum design and evaluating treatment efficiencies for anaerobic treatment technologies. The biochemical sulfide potential (BSP) assay has previously demonstrated the advantages of its time efficiency and measurement accuracy for biologically assessing substrate degradability, while its application is limited by undefined operational parameters. In this study, the BSP assay was further optimized through a systematic investigation of a critical parameter, inoculum-to-substrate ratio (ISR), and the applicable kinetic model to unravel the potential use of BSP assays for anaerobic waste treatment. Under two series of experimental scenarios, the common ISR ranges of 0.5-4.0 (based on the traditional BMP assay) and extreme ISRs (as low as 0.1) were studied, in which the advantage of a BSP assay on extreme ISRs was highlighted. Meanwhile, the underlying cause and mechanism for biodegradability discrepancies under different ISRs (0.1-6.0) were further investigated. The extracellular polymeric substance (EPS) characterization of residual organics and the two-substrate first-order hydrolysis model analyses revealed that the hydrolysis process of slowly-biodegradable organics fraction was hindered under improper ISR conditions. Furthermore, the Cone model was evaluated as more appropriate for biodegradation kinetics analysis in BSP assays among the five common kinetic models (i.e., Exponential, Fitzhugh, Cone, Transference, and modified Gompertz models). Overall, the results provide fundamental guidance on designing consistent BSP assays and put a step forward in standardizing the BSP assay for anaerobic biodegradability assessments. (c) 2021 Elsevier Ltd. All rights reserved.

关键词： Pomegranate peels   Silver nanoparticles   Haemato-biochemical variables   Oxidative stress   Innate immunity   OXIDATIVE STRESS BIOMARKERS   OREOCHROMIS-NILOTICUS   GROWTH-PERFORMANCE   AFRICAN CATFISH   RAINBOW-TROUT   BLOOD-GLUCOSE   COMMON CARP   TOXICITY   FISH   BIOACCUMULATION  

摘要： The present study investigated the adverse effects of silver nanoparticles (AgNPs) on haemato-biochemical, oxidant/antioxidant, and immunological responses of Nile tilapia (Oreochromis niloticus) as well as the beneficial roles of pomegranate (Punica granatum) peel (PP) powder to mitigate these effects. Fish (29.6-31.5 g) were fed on diets supplemented with PP at levels of 0.0% (control), 3%, and 5% and exposed to sub-lethal levels of AgNPs (0.0 and 2.0 mg/L) for six weeks. The results showed that AgNPs exposure alone significantly suppressed the fish growth and elevated stress biomarkers (blood glucose and cortisol), induced liver damage (alanine and aspartate aminotransferases), and renal failure (creatinine and uric acid). Additionally, AgNPs exposure significantly decreased serum immune parameters (lysozyme activity, respiratory burst activity, and total immunoglobulin) and affected hepatic and renal oxidant/antioxidant biomarkers (superoxide dismutase, catalase, malondialdehyde, and reduced glutathione). Dietary supplementation of PP powder alone reduced the fish performance but markedly enhanced antioxidant and immunological activities. Additionally, dietary PP powder significantly mitigated AgNPs-induced effects, attenuating hepato-renal damage, oxidative stress, and immunity biomarkers. In conclusion, AgNPs adversely affected the performance of Nile tilapia; however, dietary supplementation of 5% PP powder effectively mitigated the oxidative stress and immune suppression resulted from AgNPs exposure.