络合型含铁材料对砷胁迫下水稻生理生化特性及砷累积的影响

土壤重金属与农产品质量息息相关.本研究通过设置砷胁迫条件下水稻种植盆栽试验,分析络合型含铁材料不同施用时期和不同施用量对水稻SPAD值、抗氧化酶(SOD、POD、CAT)活性以及水稻砷吸收、累积的影响.结果表明,砷胁迫对水稻SOD、POD、CAT活性有着不同程度的抑制作用,添加络合型含铁材料可以降低水稻MDA含量,缓解砷对水稻光合作用和SOD、POD、CAT活性的抑制;同时能减少水稻对土壤砷的吸收和累积.与移栽前添加络合型含铁材料相比,选择水稻孕穗期前添加络合型含铁材料,水稻砷吸收的抑制效果较好;水稻植株地上部砷含量与络合型含铁材料的添加浓度呈显著负相关,孕穗期前添加0.2 g·kg-1络合型含铁材料对水稻植株砷的吸收抑制效果最好,水稻植株地上部砷含量降低59.22%.     

脂肪来源干细胞治疗心肌梗死的现状及策略

急性心肌梗死是最常见的心血管疾病之一,由于冠状动脉供血不全导致心肌细胞大量坏死、生存微环境恶化,近期可发生心肌细胞机械-电生理功能紊乱,远期可导致心力衰竭。目前的临床治疗方法虽能在一定程度上改善心功能,减轻心室重塑,但由于心肌细胞再生能力有限,心脏功能难以完全恢复正常。近年来,脂肪来源干细胞移植治疗急性心肌梗死受到广泛关注,但由于移植后细胞的存留和存活率普遍较低,总体治疗效果并不理想。本文对目前脂肪来源干细胞治疗急性心肌梗死的现况及提高其疗效的途径和方法作一综述。     

黄酒酿造原料及生产工艺研究现状与展望

黄酒的质量取决于酿造原料、酒曲、加工工艺以及酿造环境,不同的酿造原料、酒曲、加工工艺和环境能赋予黄酒不同的品质与风味。本文在检索文献、比较分析新旧版黄酒国标的基础上,介绍了南北地区黄酒酿造原料的差异以及新型功能性黄酒原辅料研发现状,综述了浸米、蒸饭与发酵三个工艺关键环节的最新研究进展,旨在为黄酒技术的创新,功能性、饮料性、国际性黄酒新产品开发提供借鉴及参考。     

First report of the apparent metabolisable energy value of black soldier fly larvae fat used in broiler chicken diets

In the available literature, there are limited data about the energetic value of insect-derived products. In particular, insect fat cannot be used in practical broiler nutrition due to the lack of precise apparent metabolisable energy (AME) value. Therefore, the present study aimed to investigate the AME and apparent metabolisable energy corrected to zero nitrogen balance (AME_N) levels of Hermetia illucens larvae fat for broiler chickens of various ages. A total of 400 1-day-old male Ross 308 chicks were randomly allotted to four dietary groups (10 replicate pens per treatment; 10 birds per pen). The following treatments were applied: HI0 – basal diet without dietary fat inclusion, HI03 – basal diet enriched with 30 g/kg H. illucens larvae fat, HI06 – basal diet enriched with 60 g/kg H. illucens larvae fat, and HI09 – basal diet enriched with 90 g/kg H. illucens larvae fat. Broilers had ad libitum access to mash form feed and water. Excreta samples were collected on d 14, d 28, and d 35. To determine the AME and AME_N values of H. illucens larvae fat, the simple linear regression method was used. The results show that the AME and AME_N values of H. illucens larvae fat for broiler chickens are 9 049 kcal/kg (37.86 MJ/kg) and 9 019 kcal/kg (37.74 MJ/kg), respectively. Additionally, because the birds’ age significantly (P < 0.001) affected the AME and AME_N levels, the implementation of H. illucens larvae fat to broiler diets should be considered in each nutritional period using the recommended regression model AME = 2 559.758 + 62.989 × fat inclusion (%) + 7.405 × day of age and AME_N = 2 543.2663 + 62.8649 × fat inclusion (%) + 7.3777 × day of age. The present data emphasised that the H. illucens larvae fat metabolisable energy is similar to that of soybean oil.     

Eco-efficiency of urban material metabolism: a case study in Shenzhen, China

The keys of studying urban sustainable development are material metabolism flux and efficiency. Metabolism flux of urban materials can only reflect the metabolism velocity, while its eco-efficiency can determine the metabolism capacity to support socio-economic development. The general model and the measure model of the eco-efficiency were set up, based on the source recycle (decreasing the consumption of crude resources) and the terminal recycle (decreasing the discharge of pollutants) of production and life. These models were employed to study material metabolism flux and efficiency in Shenzhen, China. Results showed that water, energy and waste metabolism fluxes have increased since 1998 with constant socio-economic development, and their eco-efficiencies have also increased rapidly. When GDP rose by 2.7 times, the metabolism fluxes of urban water and electricity rose by 1.5 and 3.0 times, respectively. When the added value of industry rose by 3.7 times, the metabolism fluxes of industrial water, electricity, energy and waste rose by 1.9, 3.5, 2.7 and 2.0 times, respectively. When population rose by 1.5 times, the metabolism fluxes of residential water and electricity rose by 1.8 and 1.7 times, respectively. During the period, the resource efficiency, environmental efficiency and eco-efficiency rose by 1.8, 3.7 and 2.3 times, respectively. Whereas the efficiency of material metabolism has been improved in Shenzhen, the scarcity of material resources has become more and more serious. Therefore, it is necessary to further improve the efficiency of material metabolism. The keys of improving the eco-efficiency of urban material metabolism are the increasing of resource and environmental efficiencies, and the establishing of the recycling chain of re-utilization of waste resources.     

A hybrid boronate affinity probe for the selective detection of cis-diol containing compounds in tea beverages

UiO-66-NH₂ nanocomposite was post-modified with 4-mercaptophenylboronic acid (MPBA) by the method of in situ hybridization reaction. The hybrid boronate affinity material UiO-NH₂@P (TEPIC-co-MPBA) was characterized by scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. The material was applied as fluorescent probe for the detection of cis-diol containing compounds based on the boronate affinity mechanism, and exhibited high specific selectively. The proposed method exhibited good linearity for the detection of catechol in the range of 0.50 to 8.00 μg ml⁻¹. The detection limit was 0.13 μg ml⁻¹. The tactic was successfully applied to analyze the total polyphenols in tea beverages for catechol, and relative recovery was in 98.86–106.00%. Therefore, this work provided a promising strategy for the recognition of cis-diol containing compounds.     

顺磁物质对土壤低场核磁共振信号特征及含水量测定的影响

核磁共振(NMR)技术由于具有高效快速、不破坏土壤结构且对人体无害等优点,逐渐被应用到土壤学相关领域研究中。然而,土壤中顺磁物质的存在对核磁共振信号特征的影响仍不明确。本研究旨在揭示顺磁物质对不同类型土壤低场核磁共振(LF-NMR)信号特征和土壤含水量测定的影响。结果表明:土壤水的LF-NMR信号量最高可达150左右,土壤矿物、有机质和微生物等固相物质的LF-NMR信号量基本不超过0.3,相对可以忽略。质地和顺磁物质对土壤水的LF-NMR信号量测量有更大影响。LF-NMR仪器存在弛豫时间监测盲区,信号量损失主要是由于顺磁物质加速了水中氢质子的弛豫过程,导致小孔隙中水分反馈的极快的LF-NMR信号不能被监测设备捕获。对于顺磁物质含量较少的壤性潮土(1.2%)和黏壤性黑土(1.3%),LF-NMR信号量损失不大,其与土壤含水量呈线性关系;但对于黏粒含量(45.3%)和顺磁物质含量(4.0%)较高的黏性红壤,测定中会损失一部分LF-NMR信号量,监测到的LF-NMR信号量与土壤含水量不再呈线性关系。此外,外源添加顺磁物质(3.0 g·L^-1的MnCl₂溶液)也会降低黑土和红壤中可被监测的LF-NMR信号量,黑土和红壤的信号量最大损失率分别为41.0%和46.7%,极大地改变其与土壤含水量之间的定量关系。因此,在利用LF-NMR测量富含顺磁物质(>1.3%)或有外源顺磁物质进入的黏性土壤的含水量时,应先通过校正降低顺磁物质等对LF-NMR信号量的影响。研究结果对利用低场核磁共振技术准确分析土壤水分分布及土壤孔隙结构具有重要意义。     

社会经济代谢研究:内涵、发现和展望

社会经济代谢是指由于人类活动导致的物质和能量在社会经济系统内部和边界上的迁移和转换。社会经济代谢研究已经成为产业生态学的核心领域。本文结合典型案例介绍了社会经济代谢研究的内涵和基本步骤,总结了社会经济代谢研究的主要发现:提供了追踪物质在社会经济系统的来源、去向和流动路径的方法与模型;揭示了物质材料及其社会经济代谢过程对现代化生产和生活方式的支撑作用;阐明了人类活动驱动与物质代谢相关的生态环境问题的机制;提供了评估资源利用效率、资源供需趋势和城市矿产开发潜力的模型与基础数据。最后指出了社会经济代谢研究的发展方向:增加研究对象并深化对每种对象的研究精度;拓展或细化研究系统的时空边界;引入并融合新的数据来源和研究方法;将社会经济代谢中的物质流对接到与其相关的生态环境影响;建立可共享、可拓展、可累积的数据平台。     

雷公藤提取物中主要物质基础及其抗肿瘤活性研究北大核心CSCD

为进一步阐明雷公藤中的主要物质基础,并评价其抗肿瘤活性。该研究采用柱层析、HPLC等技术,对雷公藤提取物进行研究。结果表明:(1)从雷公藤95%乙醇提取物中分离得到12个化合物,根据理化性质及波谱数据鉴定各化合物的结构分别为α,β-amyrenone(1)、3β-acetoxyolean-12-en-28-oic acid(2)、antriptolactone(3)、ω-hydroxypropioquaiacone(4)、3-(4-hydroxy-3-methoxyphenyl)-propenal(5)、3-methoxy-4-hydroxy phenylethanol(6)、vanillin(7)、3,4,5-三甲氧基苯酚(8)、对羟基苯甲酸(9)、对羟基苯甲醛(10)、vanillyl alcohol(11)、2,6-dimethxy-1,4-benzoquinone(12)。其中,化合物1、2、5、12为首次在该属植物中分离得到。(2)采用噻唑蓝(MTT)法对12个化合物进行抗SH-SY5Y细胞株、K562细胞株和Hel细胞株3种肿瘤细胞系细胞增殖活性的筛选,并对活性较好的化合物12进行Hoechst荧光染色和促凋亡作用的检测发现,化合物2、3、5、12具有一定的抗肿瘤活性,其中化合物12的抗肿瘤活性最为显著(SH-SY5Y细胞、Hel细胞、K562细胞的IC_(50)值分别为35.6、14.3、28.8μmol·L^(-1))。该研究结果进一步丰富了雷公藤的化学成分,发现了1个具有明显抗肿瘤活性的单体物质,为雷公藤的进一步开发提供了科学依据。     

Construction and structure studies of DNA-bipyridine complexes as versatile scaffolds for site-specific incorporation of metal ions into DNA

The facile construction of metal–DNA complexes using ‘Click’ reactions is reported here. A series of 2′-propargyl-modified DNA oligonucleotides were initially synthesized as structure scaffolds and were then modified through ‘Click’ reaction to incorporate a bipyridine ligand equipped with an azido group. These metal chelating ligands can be placed in the DNA context in site-specific fashion to provide versatile templates for binding various metal ions, which are exchangeable using a simple EDTA washing-and-filtration step. The constructed metal–DNA complexes were found to be thermally stable. Their structures were explored by solving a crystal structure of a propargyl-modified DNA duplex and installing the bipyridine ligands by molecular modeling and simulation. These metal–DNA complexes could have wide applications as novel organometallic catalysts, artificial ribonucleases, and potential metal delivery systems.