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关键词： Arsenic   Glutathione   Halophyte   Osmolytes   Phytochelatin   Phytoremediation   Salinity   Salvadora persica   Thiol metabolism   Tolerance index  

摘要： Heavy metal(loid)s contamination in soil is a major environmental concern that limits agricultural yield and threatens human health worldwide. Arsenic (As) is the most toxic non-essential metalloid found in soil which comes from various natural as well as human activities. S. persica is a facultative halophyte found abundantly in dry, semiarid and saline areas. In the present study, growth, mineral nutrient homeostasis, MDA content, phytochelatin levels, and ROS-scavenging attributes were examined in S. persica imposed to solitary treatments of salinity (250 mM and 750 mM NaCl), solitary treatments of arsenic (200 mu M and 600 mu M As), and combined treatments of As with 250 mM NaCl with an aim to elucidate salinity and As tolerance mechanisms. The results demonstrated that S. persica plants sustained under high levels of As (600 mu M As) as well as NaC1 (750 mM). The activity of superoxide dismutase, catalase, peroxidase, and glutathione reductase were either elevated or unaffected under salt or As stress. However, ascorbate peroxidase activity declined under both solitary and combination of As with NaCl. Furthermore, the cellular redox status measured in terms of reduced ascorbate/dehydroascorbate, and reduced glutathione/oxidized glutathione ratios also either increased or remained unaffected in seedlings treated with both solitary and combined treatments of As + NaCl. Significant accumulation of various oxidative stress indicators (H2O2 and O-2(center dot-)) were observed under high As stress condition. However, presence of salt with high As significantly reduced the levels of ROS. Furthermore, exogenous salt improved As tolerance index (Ti) under high As stress condition. The values of translocation factor (Tf) and As bioaccumulation factor (BF) were > 1 in all the treatments. From this study, it can be concluded that the facultative halophyte S. persica is a potential As accumulator and may find application for phytoextraction of arsenic-contaminated saline so

关键词： boron neutron capture therapy   cancer therapeutics   carbohydrates   drug delivery   glucose transporters   medicinal chemistry  

摘要： Boron neutron capture therapy ( BNCT) is a noninvasive binary therapeutic modality applicable to the treatment of cancers. While BNCT offers a tumor-targeting selectivity that is difficult to match by other means, the last obstacles preventing the full harness of this potential come in the form of the suboptimal boron delivery strategies presently used in the clinics. To address these challenges, we have developed delivery agents that target the glucose transporter GLUT1. Here, we present the chemical synthesis of a number of ortho-carboranylmethyl-substituted glucoconjugates and the biological assessment of all positional isomers. Altogether, the study provides protocols for the synthesis and structural characterization of such glucoconjugates and insights into their essential properties, for example, cytotoxicity, GLUT1-affinity, metabolism, and boron delivery capacity. In addition to solidifying the biochemical foundations of a successful GLUT1-targeting approach to BNCT, we identify the most promising modification sites in D-glucose, which are critical in order to further develop this strategy toward clinical use.

关键词： A/Ci curves   Gas exchange   Nursery management   Phosphorus partitioning   Sustainability  

摘要： Ornamental nursery producers grow a variety of plant taxa in soil-less substrates and rely on frequent water and nutrient applications to maximize plant growth and quality. This study was performed to understand the morpho-physiological basis of plant response to phosphorus (P) additions and to identify the optimum P concentration required for three common woody ornamental taxa: Hydrangea quercifolia 'Queen of Hearts', Cornus obliqua 'Powell Gardens' and Physocarpus opuhfolius 'Seward'. In a greenhouse experiment, all plants were watered with a complete nutrient solution that varied in P concentration (0, 0.7, 1.3, 2.5, 3.7, 6.5 mg L-1). Optimum P concentration for photosynthetic biochemistry was dependent on taxa and ranged between 2.5 and 3.7 mg L-1. For total dry biomass, the optimum P concentration was approximately 4.0 mg L-1 for all three taxa. Phosphorus concentration below 2.5 mg L-1 reduced leaf size and resulted in greater partitioning of biomass and P to root growth. Analysis of responses of photosynthesis to intercellular carbon dioxide concentration (A/Ci curves) indicated a continuous increase in photosynthetic parameters to increasing P concentration. Rate of rubisco for carboxylation (V-cmax), RuBP regeneration rate (J), and the rate of triose phosphate use (TPU) limited photosynthesis in P-deficient plants for all three taxa. Light-harvesting efficiency (Fv'/Fm') for all three taxa was less sensitive to P addition than photosynthetic biochemistry or plant growth. The optimal P concentrations identified in this study are lower than common recommendations and less than the amounts provided by typical commercial fertilizers. Thus, for these three taxa, application of P above 4 mg L-1 in combination with excess irrigation resulting in leachate could have negative environmental consequences without improving crop growth or physiology.

关键词： Broccoli   Brassica oleraceae L. var. italica   biomodulators   deficit-irrigation   growth   yield   shelf-life  

摘要： The present study was conducted to assess the effect of certain biomodulators (BMs) on growth, yield, and storability as well as on bioactive constituents either before or after storage of deficit-irrigated broccoli. The tested BMs were yeast extract (YE), moringa leaves extract (MLE), salicylic acid (SA) and humic acid (HA). Deficit irrigation (DI) was achieved by extending the duration between subsequent irrigations from five days (control) to either ten (IR10) or 15 days ORM. Results indicated that all applied BMs alleviated DI effects on growth and yield. Post-harvest decline in quality was delayed by DI as biomass loss percentage (BLP %) and post-harvest decay percentage (PHD %) were decreased. All applied BMs also preserved inflorescence quality during storage as BL% and PHD% were lower in BMs-treated plants compared with control. Chlorophylls, carotenoids, ascorbic acid, total phenols and total soluble carbohydrates in broccoli inflorescence were decreased in IR10 and IR15 plants whereas increased in BMs-treated plants. Anthocyanins content was not significantly affected in response to DI treatments and peroxidase activity was not significantly affected in response to either DI or BMs treatments. It was concluded that treatments with BMs could be a feasible approach to avoid yield losses in water-stressed broccoli and that treatments with BMs of deficit-irrigated plants maintain post-harvest quality of broccoli heads during storage.

关键词： Water deficit   Passion fruit   Gulupa   Gene expression   Stomatal conductance  

摘要： Water deficit stress is responsible for at least 40 % of crop losses worldwide, positioning itself as a strong threat to food security. Purple passion fruit (Passifiora edulis Sims f. edulis) is one of the most desirable exotic fruits on the world market mainly for its organoleptic properties. Information on the response to water deficit stress for purple passion fruit is scarce and in some cases contradictory. Therefore, the objective of the present work was to evaluate the morphological, physiological, biochemical and transcriptional response of purple passion fruit during water deficit and depict its strategy. The response of purple passion fruit plants to two water deficit treatments (T1 : 50 % of irrigation, T2: 0% of irrigation compared to control) was evaluated during 40 days of stress, measuring changes in physiological variables related to growth and water relations, as well as the content of metabolites related to stress and the expression of genes associated with drought stress. Results show that the plant prevents water loss, by stomata closure, modulation of growth and accumulation of proline and sugars, while promoting root growth, features associated with tolerance to water deficit. At the expression level, early transcriptional activation of PeDREB2A and PeRD21A were detected in plants under the most severe stress, while PeGO LS1 and PeAFL1 upregulation were observed in plants under milder stress. These results suggest that purple passion fruit plants display an isohydric behavior and evade water deficit stress as a response strategy, where loss of water is avoided.

关键词： Antioxidant enzyme   Growth   Flooding stress   PCA   Physiological   Spinacia oleracea L.  

摘要： Recently, flooding stress caused by nonuniform and excessive rainfall, which occurs in most regions of the world due to global climate change, has adversely affected plant growth and development. In many regions, spinach (Spinacia oleracea L.) is severely affected by flooding stress during the cultivation period. This study aimed to determine the effects of flooding stress on the morpho-physiological and biochemical properties of spinach in different harvest times. The changes in the morpho-physiological and biochemical parameters of spinach were determined at two levels of stress, including no stress and flooding stress, as well as five different harvesting times. The results demonstrate that while flooding stress reduced some growth parameters such as chlorophyll a, b and protein content, it caused statistically significant increases in proline, hydrogen peroxide (HO), malon-dialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activity. Principal Component Analysis (PCA) showed that first and second components explained 71.59 % and 73.50 % of variation under no stress and flooding stress conditions, respectively. Correlation and PCA analysis revealed that relative leaf water content (LWC), membrane damage, and chlorophyll a and b are important parameters as they are affected in response to flooding stress. Thus, the flooding stress occurring at harvest times negatively affected the growth and development of spinach and caused significant changes in the morpho-physiological and biochemical properties.

关键词： Age   in vitrofertilization   biochemical pregnancy loss   single embryo transfer  

摘要： Introduction As women age, the increasing rate of aneuploidy lead to an augmentation in the incidence of clinical miscarriages. It was anticipated that biochemical pregnancy rates would also rise with maternal age. However, no study has previously evaluated the effect of maternal age on biochemical pregnancy rates. Material and methods A retrospective cohort study of 2177 subjects who underwent single embryo transfer (SET) as part of a fresh or thawed IVF cycle were recruited from 2008 through 2012, resulting in 952 pregnancies. Data was stratified for age and compared using analysis of variance (continuous data) and chi-squared tests (categorical data). Results The likelihood of a clinical miscarriage increased with age (p < .001). Surprisingly, advancing age had no effect on the biochemical pregnancy loss rate (p = .72) (Age 21-30 y: 10.7%, Age 31-35 y:9.8%, Age 36-40y:11.5%, Age 41-42 y:13.6%). Conclusions Biochemical pregnancy loss rate did not increase as a function of age in women 21 to 42 years of age.

关键词： 逆向教学设计   深度课堂   核心素养   生物化学  

摘要： 以生物化学为例,首先对课堂教学中存在的“浅层教学”和“浅层学习”现象进行深刻反思,然后论述了深度课堂的价值意蕴和基本内涵,并提出了深度课堂构建的教学逻辑,即从学情分析、教学目标和教学评价三个方面进行逆向教学设计,在此基础上通过深度教学和深度学习两个维度来构建深度课堂,从而实现核心素养培育目标。最后对深度课堂构建进行了展望。

关键词： 慕课   应用型本科院校   食品化学实验   教学改革  

摘要： 在互联网技术不断普及应用下,推动"互联网+教育"是我国当前教育主流趋势,这在很大程度上改变了以往传统教育教学模式.而慕课作为其产物,将其运用到"食品化学实验"课程中,可以提升学生生实践能力,增强师生互动性,从而有效提升课程教育质量,促使学生更好的发展.本文首先阐述了慕课的概念,其次分析了当前应用型本科院校"食品化学实验"课程现状,并提出了慕课下的课程教学改革实践方法.

关键词： 金课   植物生物化学   农林类专业   高质量人才  

摘要： 植物生物化学是国内高等农林院校相关专业学生需要掌握的重要基础知识,对农林类专业人才的培养尤为重要.为顺应教育部提出的淘汰"水课"、打造"金课"的教学理念,本文紧扣"两性一度",围绕农林院校相关专业特点和学生的知识结构、学习方法、学习兴趣等,具有针对性的探讨分析植物生物化学一流课程建设途径与思路,力争将该课程建设成为一门"金课"并在国内进行推广,为培养符合新时代中国特色社会主义需求的创新型、高质量人才提供参考与借鉴.