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991.
Adam J. Bates Jon P. Sadler Glyn Everett Dave Grundy Norman Lowe George Davis David Baker Malcolm Bridge Jon Clifton Roger Freestone David Gardner Chris Gibson Robin Hemming Stephen Howarth Steve Orridge Mark Shaw Tom Tams Heather Young 《Entomologia Experimentalis et Applicata》2013,146(3):386-397
Done well, citizen science projects can gather datasets of a size and scope far larger than would be possible using professional researchers. This study uses data gathered in Britain by the Garden Moth Scheme (GMS). Participants run garden light traps for at least 26 weeks a year and complete garden questionnaires detailing garden habitat and nearby landscape features. We used data exploration and generalised linear modelling (GLM) to investigate whether the data can be used to generate reliable research findings, testing the effect of moth light trap type on moth catch. Robinson traps, then Skinner traps, then Heath traps were found to catch the highest abundance and diversity of moths. Mercury vapour bulbs, then blended light bulbs, then actinic bulbs collected the highest abundance and diversity of moths. The GMS dataset can be used to generate useful and reliable research findings, and can be used in the future to investigate temporal and spatial trends in moth assemblage. Under international law, the use of mercury vapour bulbs will be phased out in coming years, leading to changes in the way moth assemblages are sampled. Information on the relative efficacy of different bulb types will aid the analysis of long‐term moth datasets after these changes. 相似文献
992.
Susan Winch Danielle Fortin David R. S. Lean Michael Parsons 《Geomicrobiology journal》2013,30(2):112-129
Large quantities of Hg remain in tailings dumps from historical Nova Scotian gold mines. Depth profiles of total Hg (HgT) and methylmercury (MeHg) were compared with geochemical and microbiological variables, to identify factors influencing MeHg levels in tailings. HgT and MeHg were highly variable in tailings (0.2–73.5 μ mol kg? 1 and < dl-56.4 nmol kg? 1, respectively), and were influenced by a complex set of in situ factors. Elevated MeHg was linked with > 5 μ mol kg?1 HgT, organic matter, hydrology, abundance and activity of sulfate reducing bacteria, and demethylation processes. Methylmercury levels in tailings from a wet, bog-like site appeared to undergo seasonal fluctuations, with higher concentrations measured in September and October, and lower concentrations in May. Evaluations of amalgamation tailings should examine MeHg and HgT transport out of low-lying, saturated tailings dumps after snowmelt and major rainfall events, and should take into account the possibility of seasonal variation in MeHg levels in northern regions. 相似文献
993.
Background and Aims
Ontogenetic patterns of odour emissions and heating associated with plant reproductive structures may have profound effects on insect behaviour, and consequently on pollination. In some cycads, notably Macrozamia, temporal changes in emission of specific odour compounds and temperature have been interpreted as a ‘push–pull’ interaction in which pollinators are either attracted or repelled according to the concentration of the emitted volatiles. To establish which mechanisms occur in the large Encephalartos cycad clade, the temporal patterns of volatile emissions, heating and pollinator activity of cones of Encephalartos villosus in the Eastern Cape (EC) and KwaZulu Natal (KZN) of South Africa were investigated.Methods and Key Results
Gas chromatography–mass spectrometry (GC-MS) analyses of Encephalartos villosus cone volatiles showed that emissions, dominated by eucalyptol and 2-isopropyl-3-methoxypyrazine in EC populations and (3E)-1,3-octadiene and (3E,5Z)-1,3,5-octatriene in the KZN populations, varied across developmental stages but did not vary significantly on a daily cycle. Heating in male cones was higher at dehiscence than during pre- and post-dehiscence, and reached a maximum at about 1830 h when temperatures were between 7·0 and 12·0 °C above ambient. Daily heating of female cones was less pronounced and reached a maximum at about 1345 h when it was on average between 0·9 and 3·0 °C above ambient. Insect abundance on male cones was higher at dehiscence than at the other stages and significantly higher in the afternoon than in the morning and evening.Conclusions
There are pronounced developmental changes in volatile emissions and heating in E. villosus cones, as well as strong daily changes in thermogenesis. Daily patterns of volatile emissions and pollinator abundance in E. villosus are different from those observed in some Macrozamia cycads and not consistent with the push–pull pattern as periods of peak odour emission do not coincide with mass exodus of insects from male cones. 相似文献994.
Hulya Azakli Candan Gurses Muzaffer Arikan Aydın Aydoseli Yavuz Aras Altay Sencer Aysen Gokyigit Bilge Bilgic Duran Ustek 《Gene》2013
Introduction
Hippocampal sclerosis is the most common lesion in patients with mesial temporal lobe epilepsy. Recently, there has been growing evidence on the involvement of mitochondria also in sporadic forms of epilepsy. In addition, it has been increasingly argued that mitochondrial dysfunction has an important role in epileptogenesis and seizure generation in temporal lobe epilepsy. Although mtDNA polymorphisms have been identified as potential risk factors for neurological diseases, the link between homoplasmy and heteroplasmy within tissues is not clear. We investigated whether mitochondrial DNA (mtDNA) polymorphisms are involved in a case report of a patient with mesial temporal lobe epilepsy-hippocampal sclerosis (MTLE-HS).Design
We report the whole genome mtDNA deep sequencing results and clinical features of a 36-year-old woman with MTLE-HS. We used pyrosequencing technology to sequence a whole mitochondrial genome isolated from six different regions of her brain and blood. To assess the possible role of mitochondrial DNA variations in affected tissues, we compared all specimens from different regions of the hippocampus and blood.Results
In total, 35 homoplasmic and 18 heteroplasmic variations have been detected in 6 different regions of the hippocampus and in blood samples. While the samples did not display any difference in homoplasmic variations, it has been shown that hippocampus regions contain more heteroplasmic variations than blood. The number of heteroplasmic variations was highest in the CA2 region of the brain and accumulated in ND2, ND4 and ND5 genes. Also, dentate and subiculum regions of the hippocampus had similar heteroplasmic variation profiles.Discussion
We present a new rare example of parallel mutation at 16223 position. Our case suggests that defects in mitochondrial function might be underlying the pathogenesis of seizures in temporal lobe epilepsy. 相似文献995.
Yoshiki Katoh Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(7):1537-1541
Polynucleotides could be synthesized from nucleoside diphosphates by microorganisms belonging to genera Pseudotnonas, Serratia, Xatuhonwnas, Proteus, Aerobacter, Bacillus, and Brevibacterium. These strains were rich in polynucleotide phosphorylase easily extractable from cells and poor in both nuclease and nucleoside-diphosphate-degrading enzymes. Polynucleotide phosphorylase was effectively extracted from the bacterial cells, that had been once soaked in saturated saline solution, with hypotonic solution. Synthesis of polynucleotides was observed not only when the substrates were incubated with polynucleotide phosphorylase preparation isolated from the bacterial cells, but also when the substrates were added directly to the bacterial cultures. 相似文献
996.
Kurt J. Irgolic 《Chemical Speciation and Bioavailability》2013,25(2):45-46
AbstractThe stability constants of binary complexes of 2,4-dichlorophenoxyacetic acid (2,4-D), (4-chloro-2-methylphenoxy)acetic acid (2,4-MCPA) and (4-chloro-2-methylphenoxy) propionic acid (2,4-MCPP) with Hg(II), Pb(II) have been calculated at 298 K and at ionic strength μ = 0.1 (NaNO3). Potentiometric measurements display two hydroxide complexes for Hg(II): HgH?1A and HgH?2A2 whereas for Pb(II) we observe the formation of three species PbH?1A, PbH?1A2 and PbH?2A2. With regard to the successive complexes, no other system represents this type of complexes under our experimental conditions. The order of capacity of complexation compared to metal for the three ligands is Hg(II)4Pb(II). Finally, the study in solution has been completed by a quantum examination of the structures of the complex of Hg(II) by the AM1 method. 相似文献
997.
Mingzhang Gao Min Wang Kathy D. Miller Qi-Huang Zheng 《Bioorganic & medicinal chemistry letters》2013,23(15):4342-4346
(Z)-2-((1H-Indazol-3-yl)methylene)-6-methoxy-7-(piperazin-1-ylmethyl)benzofuran-3(2H)-one is a potent and selective proviral integration site in moloney murine leukemia virus kinase 1 (PIM1) inhibitor with an IC50 value of 3 nM. (Z)-2-((1H-Indazol-3-yl)methylene)-6-[11C]methoxy-7-(piperazin-1-ylmethyl)benzofuran-3(2H)-one, a new potential PET probe for imaging of the enzyme PIM1, was first designed and synthesized in 20–30% decay corrected radiochemical yield and 370–740 GBq/μmol specific activity at end of bombardment (EOB). The synthetic strategy was to prepare a carbon-11-labeled Boc-protected intermediate followed by a quick acidic de-protection. 相似文献
998.
Field emission scanning electron microscopy (FESEM) preparation techniques have been successfully adapted for visualization of the internal and external ultrastructure of Mougeotia filaments and protoplasts. FESEM of the innermost layer of cell wall in Mougeotia filaments revealed that microfibrils are deposited parallel to each other in an interconnected mesh and are oriented perpendicular to the direction of elongation. For the first time, the surface of protoplasts at different stages of regeneration has been observed using FESEM. Nascent microfibril deposition occurs between 1 and 2 h after isolation and arrangement of these microfibrils is random for at least 8 h. Observation of the inner surface of the plasma membrane in burst protoplasts showed that microtubules are not strongly attached for at least 3 h after protoplast isolation. 相似文献
999.
干湿交替频率对不同土壤CO2和N2O释放的影响 总被引:4,自引:0,他引:4
干旱、半干旱和地中海气候区,乃至一些湿润地区,由干湿交替引起的土壤碳、氮的短暂脉冲式释放很大程度上决定着长时间尺度温室气体释放的总量,是土壤碳、氮温室气体释放的关键过程.选择我国降雨梯度下的森林、农田、草地和荒漠生态系统,采集土样进行实验室统一控制条件下的多重干湿交替循环,对比探讨不同生态系统土壤干湿交替频率对CO2和N2O释放的影响模式.结果表明:(1)干湿交替能够显著的激发土壤中CO2和N2O的释放,森林、农田、草地和荒漠土壤CO2和N2O释放速率对干湿交替的响应模式基本一致,其响应强度与土壤本底中碳和氮的含量有关;(2)在一定培养时间内,随着干湿交替频率的增加,土壤再湿润阶段CO2释放速率降低,但是,气体释放的总量较之于恒湿对照组有所增加.(3)不同土壤N2O的释放总量对于湿交替频率的响应模式表现出很大的差异,其中农田和荒漠土壤响应模式类似. 相似文献
1000.
土壤氧气可获得性对双季稻田温室气体排放通量的影响 总被引:5,自引:0,他引:5
为探讨土壤氧气可获得性(SOA)对双季稻田温室气体排放的影响,利用静态箱气相色谱法对多种管理措施影响下稻田温室气体排放通量和土壤氧化还原电位(Eh)、pH值及田间淹水深度(H)等3种SOA因子进行了观测。结果表明,甲烷(CH4)排放最集中的Eh值、pH值和H范围分别为-100-0mV、5 < pH < 6和1-5cm,3个范围内分别观测到48.8%、61.1%和77.0%的CH4排放,其中H对CH4排放影响最明显,单独由其就可解释37.8%的CH4排放通量(P < 0.0001)。对于氧化亚氮(N2O),观测到较多的负通量,其纯排放最密集的3种SOA因子的范围分别是:0-100mV、5 < pH < 6和1-5cm,而200-300mV是其排放的临界Eh范围,高于此范围N2O排放极少。厌氧的反硝化过程是双季稻田N2O产生的主导过程。可为水稻田温室气体排放机理研究提供基础数据。 相似文献