未来升温1.5℃与2.0℃背景下中国玉米产量变化趋势评估

基于ISI-MIP推荐的5个气候模式在4个RCP情景下的模拟结果,筛选21世纪末全球升温最接近1.5℃和2.0℃的气候数据,运用作物模型DSSAT,模拟升温1.5℃和2.0℃背景下中国玉米产量相对于基准时段1985-2006年的变化,揭示了1.5℃与2.0℃升温背景下中国玉米产量变化的空间分布。结果表明：升温2.0℃背景下玉米减产风险明显高于升温1.5℃,未来升温2.0℃背景下中国玉米减产面积比升温1.5℃背景下多6.2%,升温1.5℃和2.0℃背景下中国玉米平均减产幅度分别为3.7%和11.5%;从空间分布来看,升温1.5℃与2.0℃背景下未来中国玉米产量变化在区域分布上大致相似,但未来玉米增产和减产的面积和幅度不尽相同,在北方与西南玉米种植区都有一定的增产区域,其它区域大多以减产为主,其中西北部玉米种植区减幅最大;1.5℃升温背景下北方大部分地区气候条件对玉米生长有利,2.0℃升温背景下北方地区玉米减产也不明显,说明从近期到未来一段时间内,将全球升温控制在1.5℃以内,北方地区玉米仍具有一定增产潜力。     

Higher yield of cherry tomato grown in culture medium with microbially inoculated feather compost without fertilizer application

Arthrobacter ureafaciens K10, with multiple functions, such as feather degradation, phosphate solubilization, and IAA formation, and Streptomyces sp. CP3, with pitaya cladode‐degrading ability, were co‐inoculated in compost composed of pitaya‐pruning waste (PPW), spent mushroom waste (SMW), and duck feathers (DF) in order to produce a compost called Sapf‐M. Another compost, called Sapf, was manufactured via the same composting procedure but without inoculation. The two compost products were slightly acidic and had a bulk density less than 0.25 g cm^?3, a water‐holding capacity (WHC) greater than 85%, a C : N ratio of nearly 10, and a germination index higher than 85%. Higher IAA concentration, EC, phosphate‐solubilizing bacterial numbers, actinobacterial numbers, and water‐soluble nutrients, such as ammonium, magnesium, copper, manganese, and iron, were found in Sapf‐M compared to Sapf. Five different culture media were prepared: peat mixed with Sapf at a 2 : 1 volume ratio (P‐Sapf), peat mixed with Sapf‐M at a 2 : 1 volume ratio (P‐Sapf‐M), Sapf, Sapf‐M, and peat. Each of these was analyzed for its ability to produce cherry tomatoes without fertilization. Higher WHC and water‐soluble ammonium were found in P‐Sapf‐M than in P‐Sapf. Cherry tomato cultured in P‐Sapf‐M showed the highest fruit number and yielded 1.04 kg per plant. Fruit firmness, splitting rate, BER incidence, TSS/acidity, and nutrition were all analyzed. After eradication, the mineral concentrations of roots and culture media were also determined. The results of this study show that the bio‐inoculated Sapf‐M had longer‐lasting fertility and greater plant growth‐promoting abilities than the Sapf when used as the growing medium for cherry tomato production without further fertilization.     

Different central manifestations in response to electroacupuncture at analgesic and nonanalgesic acupoints in rats: a manganese-enhanced functional magnetic resonance imaging study

Acupuncture analgesia is an important issue in veterinary medicine. This study was designed to elucidate central modulation effects in response to electroacupuncture (EA) at different acupoints. Manganese-enhanced functional magnetic resonance imaging was performed in Sprague-Dawley rats after sham acupuncture, sham EA, or true EA at somatic acupoints. The acupoints were divided into 3 groups: group 1, analgesic acupoints commonly used for pain relief, such as Hegu (LI 4); group 2, nonanalgesic acupoints rarely used for analgesic effect, such as Neiguan (PC 6); and group 3, acupoints occasionally used for analgesia, such as Zusanli (ST 36). Image acquisition was performed on a 1.5-T superconductive clinical scanner with a circular polarized extremity coil. The results showed that there was no neural activation caused by EA at a true acupoint with shallow needling and no electric current (sham acupuncture). When EA at a true acupoint was applied with true needling but no electric current (sham EA), there was only a slight increase in brain activity at the hypothalamus; when EA was applied at a true acupoint with true needling and an electric current (true EA), the primary response at the hypothalamus was enhanced. Also, there was a tendency for the early activation of pain-modulation areas to be prominent after EA at analgesic acupoints as compared with nonanalgesic acupoints. In conclusion, understanding the linkage between peripheral acupoint stimulation and central neural pathways provides not only an evidence-based approach for veterinary acupuncture but also a useful guide for clinical applications of acupuncture.     

佛甲草中SOD提取条件的优化

对景天科植物佛甲草超氧化物歧化酶(SOD)的抽提缓冲液pH值,抽提时间,热处理的温度和时间进行正交实验,并对丙酮沉淀法和硫酸铵盐析法初步纯化SOD粗酶液进行了优化和比较。结果表明:抽提缓冲液的pH值为7.8,抽提时间为2 h,热处理温度为50℃,热处理时间为15 min时,得到佛甲草SOD的相对最大提取酶活力;饱和度为90%的硫酸铵盐析是初步纯化佛甲草SOD的最优条件,其纯化倍数为4.10,回收率为0.71,为进一步的层析以制备更纯佛甲草SOD提供了理论的条件。     

冻融损伤对再生混凝土耐久性及与钢筋粘结性能分析

制作掺入引气剂和未掺入引气剂的100%粗骨料取代率的再生混凝土RC1和RC2两组试件以及掺入引气剂和未掺入引气剂的普通混凝土NC1和NC2两组试件,并分别对经过不同次数冻融循环试件的抗压强度、质量损失率、动弹性模量损失率进行研究。结果表明,冻融后各组试件的抗压强度、质量损失率及动弹性模量损失率均降低,对于添加引气剂的NC1和RC1两组试件损失较小,其中RC1组试件在200次冻融后抗压强度损失接近40%,质量损失率达0.5%,动弹性模量损失率38.5%。100%取代率并加入引气剂的ZRC组试件冻融后进行中心拨出实验,发生劈裂破坏和钢筋拔出破坏2种形式。再生粗骨料混凝土与钢筋的极限粘结应力均随冻融次数的增加而降低,200次冻融后极限粘结应力下降33.5,荷载滑移曲线既有上升段也有下降段。