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991.
Mei‐Hong Yang Hong‐Xia Liu Jin‐Long Liu Xiao‐Yuan Jing Jin‐Tong Zhang Li‐Hua Fan Shi‐Fei Wang 《Entomologia Experimentalis et Applicata》2015,154(3):199-205
Extracts of the female sex pheromone gland of the carpenterworm moth, Holcocerus vicarius (Walker) (Lepidoptera: Cossidae), a pest of Ulmus pumila L. (Ulmaceae), were found to contain Z7‐tetradecenyl acetate (Z7‐14Ac), E3‐tetradecenyl acetate (E3‐14Ac), (Z3,E5)‐tetradecenyl acetate (Z3,E5‐14Ac), and Z7‐tetradecenyl alcohol (Z7‐14OH) by coupled gas chromatographic‐electroantennographic detection (GC‐EAD) and coupled gas chromatography‐mass spectrometry (GC‐MS). Field trapping studies with impregnated rubber septa indicated that Z7‐14Ac was essential for attraction of males of H. vicarius. However, the most attractive blend contained Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH in a 50:22:17:10 ratio. Our results demonstrated that a blend of Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH represented the sex pheromone of H. vicarius. The optimized four‐component lure blend may be useful for monitoring H. vicarius infestations and mating disruption. 相似文献
992.
Do Insectivorous Birds use Volatile Organic Compounds from Plants as Olfactory Foraging Cues? Three Experimental Tests 下载免费PDF全文
Tuuli‐Marjaana Koski Toni Laaksonen Elina Mäntylä Suvi Ruuskanen Tao Li Patricia Sarai Girón‐Calva Liisa Huttunen James D. Blande Jarmo K. Holopainen Tero Klemola 《Ethology : formerly Zeitschrift fur Tierpsychologie》2015,121(12):1131-1144
Some insectivorous birds orient towards insect‐defoliated trees even when they do not see the foliar damage or the herbivores. There are, however, only a few studies that have examined the mechanisms behind this foraging behaviour. Previous studies suggest that birds can use olfactory foraging cues (e.g. volatile organic compounds (VOCs) emitted by defoliated plants), indirect visual cues or a combination of the two sensory cues. VOCs from insect‐defoliated plants are known to attract natural enemies of herbivores, and researchers have hypothesized that VOCs could also act as olfactory foraging cues for birds. We conducted three experiments across a range of spatial scales to test this hypothesis. In each experiment, birds were presented with olfactory cues and their behavioural responses or foraging outcomes were observed. In the first experiment, two different VOC blends, designed to simulate the volatile emissions of mountain birch (Betula pubescens ssp. czerepanovii) after defoliation by autumnal moth (Epirrita autumnata) larvae, were used in behavioural experiments in aviaries with pied flycatchers (Ficedula hypoleuca). The second experiment was a field‐based trial of bird foraging efficiency; the same VOC blends were applied to mountain birches, silver birches (B. pendula) and European white birches (B. pubescens) with plasticine larvae attached to the trees to serve as artificial prey for birds and provide a means to monitor predation rate. In the third experiment, the attractiveness of silver birch saplings defoliated by autumnal moth larvae versus intact controls was tested with great tits (Parus major) and blue tits (Cyanistes caeruleus) in an aviary. Birds did not orient towards either artificial or real trees with VOC supplements or towards herbivore‐damaged saplings when these saplings and undamaged alternatives were hidden from view. These findings do not support the hypothesis that olfactory foraging cues are necessary in the attraction of birds to herbivore‐damaged trees. 相似文献
993.
Drastic Layer‐Number‐Dependent Activity Enhancement in Photocatalytic H2 Evolution over nMoS2/CdS (n ≥ 1) Under Visible Light 下载免费PDF全文
Kun Chang Mu Li Tao Wang Shuxin Ouyang Peng Li Lequan Liu Jinhua Ye 《Liver Transplantation》2015,5(10)
Exploiting noble‐metal‐free cocatalysts is of huge interest for photocatalytic water splitting using solar energy. As an efficient cocatalyst in photocatalysis, MoS2 is shown promise as a low‐cost alternative to Pt for hydrogen evolution. Here we report a systematical study on controlled synthesis of MoS2 with layer number ranging from ≈1 to 112 and their activities for photocatalytic H2 evolution over commercial CdS. A drastic increase in photocatalytic H2 evolution is observed with decreasing MoS2 layer number. Particularly for the single‐layer (SL) MoS2, the SL‐MoS2/CdS sample reaches a high H2 generation rate of ≈2.01 × 10?3m h?1 in Na2S–Na2SO3 solutions and ≈2.59 × 10?3m h?1 in lactic acid solutions, corresponding to an apparent quantum efficiency of 30.2% and 38.4% at 420 nm, respectively. In addition to the more exposed edges and unsaturated active S atoms, valence band–XPS and Mott–Schottky plots analysis indicate that the SL MoS2 has the more negative conduction band energy level than the H+/H2 potential, facilitating the hydrogen reduction. 相似文献
994.
995.
Is Yield Increase Sufficient to Achieve Food Security in China? 总被引:3,自引:0,他引:3
Increasing demand for food, driven by unprecedented population growth and increasing consumption, will keep challenging food security in China. Although cereal yields have substantially improved during the last three decades, whether it will keep thriving to meet the increasing demand is not known yet. Thus, an integrated analysis on the trends of crop yield and cultivated area is essential to better understand current state of food security in China, especially on county scale. So far, yield stagnation has extensively dominated the main cereal-growing areas across China. Rice yield is facing the most severe stagnation that 53.9% counties tracked in the study have stagnated significantly, followed by maize (42.4%) and wheat (41.9%). As another important element for production sustainability, but often neglected is the planted area patterns. It has been further demonstrated that the loss in productive arable land for rice and wheat have dramatically increased the pressure on achieving food security. Not only a great deal of the planted areas have stagnated since 1980, but also collapsed. 48.4% and 54.4% of rice- and wheat-growing counties have lost their cropland areas to varying degrees. Besides, 27.6% and 35.8% of them have retrograded below the level of the 1980s. The combined influence (both loss in yield and area) has determined the crop sustainable production in China to be pessimistic for rice and wheat, and consequently no surprise to find that more than half of counties rank a lower level of production sustainability. Therefore, given the potential yield increase in wheat and maize, as well as substantial area loss of rice and wheat, the possible targeted adaptation measures for both yield and cropping area is required at county scale. Moreover, policies on food trade, alongside advocation of low calorie diets, reducing food loss and waste can help to enhance food security. 相似文献
996.
Zhiyong Yang Yushun Zhang Liming Dong Chong Yang Shanmiao Gou Tao Yin Heshui Wu Chunyou Wang 《PloS one》2015,10(5)
ObjectiveFew data are available on the potential role of inflammatory mediators and T lymphocytes in persistent organ failure (POF) in acute pancreatitis (AP). We conducted a retrospective study to characterize their role in the progression of POF in AP.MethodsA total of 69 AP patients presented within 24 hours from symptom onset developing organ failure (OF) on admission were included in our study. There were 39 patients suffering from POF and 30 from transient OF (TOF). On the 1st, 3rd and 7th days after admission, blood samples were collected for biochemical concentration monitoring including serum IL-1β, IL-6, TNF-α and high-sensitivity C-reactive protein (hs-CRP). The proportions of peripheral CD4+ and CD8+ T lymphocytes were assessed based on flow cytometry simultaneously.ResultsPatients with POF showed a significantly higher value of IL-1β and hs-CRP on day 7 compared with the group of TOF (P < 0.05). Proportions of CD4+ T cells on days 1, 3, 7 and CD4+ / CD8+ ratio on day 1 were statistically lower in the group of POF patients (P < 0.05). A CD4+ T cell proportion of 30.34% on day 1 predicted POF with an area under the curve (AUC) of 0.798, a sensitivity with 61.54% and specificity with 90.00%, respectively.ConclusionsThe reduction of peripheral blood CD4+ T lymphocytes is associated with POF in AP, and may act as a potential predictor. 相似文献
997.
Phenylephrine enhances glutamate release in the medial prefrontal cortex through interaction with N‐type Ca2+ channels and release machinery 下载免费PDF全文
Fei Luo Si‐hai Li Hua Tang Wei‐ke Deng Yu Zhang Ying Liu 《Journal of neurochemistry》2015,132(1):38-50
α1‐adrenoceptors (α1‐ARs) stimulation has been found to enhance excitatory processes in many brain regions. A recent study in our laboratory showed that α1‐ARs stimulation enhances glutamatergic transmission via both pre‐ and post‐synaptic mechanisms in layer V/VI pyramidal cells of the rat medial prefrontal cortex (mPFC). However, a number of pre‐synaptic mechanisms may contribute to α1‐ARs‐induced enhancement of glutamate release. In this study, we blocked the possible post‐synaptic action mediated by α1‐ARs to investigate how α1‐ARs activation regulates pre‐synaptic glutamate release in layer V/VI pyramidal neurons of mPFC. We found that the α1‐ARs agonist phenylephrine (Phe) induced a significant enhancement of glutamatergic transmission. The Phe‐induced potentiation was mediated by enhancing pre‐synaptic glutamate release probability and increasing the number of release vesicles via a protein kinase C‐dependent pathway. The mechanisms of Phe‐induced potentiation included interaction with both glutamate release machinery and N‐type Ca2+ channels, probably via a pre‐synaptic Gq/phospholipase C/protein kinase C pathway. Our results may provide a cellular and molecular mechanism that helps explain α1‐ARs‐mediated influence on PFC cognitive functions.
998.
999.
Diabetic nephropathy (DN) is a major diabetic complication. However, the initiating molecular events triggering DN are unknown. In this study we focused on microRNA-451 (miR-451), which is downregulated during early DN. We found that miR-451 negatively regulated the expression of Ywhaz through Ywhaz 3'UTR and that Ywhaz was required for the miR-451-mediated downregulation of p38 MAPK signalling. Moreover, over-expression of miR-451 inhibits glomerular mesangial cell proliferation in vitro and in vivo. These findings suggest that the growth-inhibitory effect of miR-451 may be explained in part by miR-451-induced suppression of Ywhaz and p38 MAPK signalling, providing evidence for the potential role of miR-451 in early DN. 相似文献
1000.
Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) were considered two alternative pathways of dissimilatory nitrate reduction. In this study, we firstly reported that both denitrification and DNRA occurred in Pseudomonas alcaliphila strain MBR with an electrode as the sole electron donor in a double chamber bio‐electrochemical system (BES). The initial concentration of nitrate appeared as a factor determining the type of nitrate reduction with electrode as the sole electron donor at the same potential (?500 mV). As the initial concentration of nitrate increased, the fraction of nitrate reduced through denitrification also increased. While nitrite (1.38 ± 0.04 mM) was used as electron acceptor instead of nitrate, the electrons recovery via DNRA and denitrification were 43.06 ± 1.02% and 50.51 ± 1.37%, respectively. The electrochemical activities and surface topography of the working electrode catalyzed by strain MBR were evaluated by cyclic voltammetry and scanning electron microscopy. The results suggested that cells of strain MBR were adhered to the electrode, playing the role of electron transfer media for nitrate and nitrite reduction. Thus, for the first time, the results that DNRA and denitrification occurred simultaneously were confirmed by powering the strain with electricity. The study further expanded the range of metabolic reactions and had potential value for the recognization of dissimilatory nitrate reduction in various ecosystems. Biotechnol. Bioeng. 2012; 109: 2904–2910. © 2012 Wiley Periodicals, Inc. 相似文献