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The composition and diversity of natural regeneration of tree species in gaps under different intensities of forest disturbance

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Journal of Forestry research 2021年第5期32卷 1843-1853页

作者： Maame Esi hammond radek Pokorný Daniel Okae-Anti Augustine Gyedu Irene Otwuwa Obeng Department of Silviculture Faculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 361300 BrnoCzech Republic Department of Soil Science School of AgricultureUniversity of Cape CoastP.M.BCape CoastGhana Forestry Services Division(FSD) P.M.BKumasiGhana 4 Madina-AccraGhana

The positive ecological interaction between gap formation and natural regeneration has been examined but little resear.h.has been carried out on the effects of gaps on natural regeneration in forests under different intensities of *** study evaluates the composition,diversity,regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed,intermittently disturbed,and disturbed forest *** Tano Forest reserve in Ghana was the study area and three gaps each were selected in the three forest site *** circular subsampling areas of 1 m2 were delineated at 2 m spacing along nor.h.south,east,and west transects within individual *** on natural regenerationheight were *** results show that the intensity of disturbance was disproportional to gap *** diversity differed significantly between undisturbed and disturbed sites and,also between intermittently disturbed and disturbed sites for Simpson’s(1-D),Equitability(J),and Berger-Parker(B-P)***,there was no significant difference among forest sites for Shannon diversity(h)and Margalef richness(MI)*** species composition on the sites *** density on the disturbed site was significantly higher than on the two other *** abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent *** species giving way to shade tolerant species is a natural process,thus make them worst variant in gap regeneration.

关键词： Disturbed Intermittently disturbed Undisturbed Forest sites Gap regeneration

Cadmium isotope fractionation reveals genetic variation in Cd uptake and translocation by Theobroma cacao and role of natural resistanceassociated macrophage protein 5 and heavy metal ATPase-family transporters

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horticulture research 2020年第1期7卷 2006-2016页

作者： rebekah E.T.Moore Ihsan Ullah Vinicius hde Oliveira Samantha J.hammond Stanislav Strekopytov Mark Tibbett Jim M.Dunwell Mark r.h.ämper Department of Ear.h.Science and Engineering Imperial CollegeLondon SW72BPUK School of Agriculture Policy and DevelopmentUniversity of ReadingReading RG66BZUK School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton Keynes MK76AAUK Imaging and Analysis Centre The Natural History MuseumLondon SW75BDUK Present address:Department of Plant Biology Institute of BiologyUniversity of CampinasCampinasSao Paulo 13083-970Brazil Present address:National Measurement Laboratory LGCQueen’s RoadTeddington TW110LYUK

In response to new European Union regulations,studies are underway to mitigate accumulation of toxic cadmium(Cd)in cacao(Theobroma cacao,Tc).This study advances such resear.h.with Cd isotope analyses of 19 genetically diverse cacao clones and yeast transformed to express cacao natural resistance-associated macrophage protein(NrAMP5)and heavy metal ATPases(hMAs).The plants were enriched in light Cd isotopes relative to the hydroponic solution withΔ^(114/110)Cd_(tot-sol)=−0.22±0.08‰.Leaves show a systematic enrichment of isotopically heavy Cd relative to total plants,in accord with closed-system isotope fractionation ofΔ^(114/110)C_(dseq-mob)=−0.13‰,by sequestering isotopically light Cd in roots/stems and mobilisation of remaining Cd to *** findings demonstrate that(i)transfer of Cd between roots and leaves is primarily unidirectional;(ii)different clones utilise similar pathways for Cd sequestration,which differ from those of other studied plants;(iii)clones differ in their efficiency of Cd *** yeast that expresses TcNrAMP5(*** natural resistance-associated macrophage gene)had isotopically lighter Cd than did *** suggests that NrAMP5 transporters constitute an important pathway for uptake of Cd by *** isotope signatures of transgenic yeast expressing hMA-family proteins suggest that they may contribute to Cd *** data are the first to record isotope fractionation induced by transporter proteins in vivo.

关键词： roots transformed signature

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英国保险/解除保险系统的发展

探测与控制学报 1989年第4期17卷 15-18页

作者： h.hammond 张卫

本文扼要介绍皇家军备研究和发展局与英国工业部门目前共同在电子保险/解除保险系统领域所进行的研究工作。

关键词：解除保险研究和发展工业部门样机模型传爆序列失效概率研究工作战斗部点火电路设计方案

The genetics of radiocaesium accumulation in plants

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The genetics of radiocaesium accumulation in plants

regulation of resource Partitioning Coordinates Nitrogen and rhizobia responses and Autoregulation of Modulation in Medicago tmncatula

The First International Workshop on Plant Ionomics

作者： P.J. White h.C. Bowen M.r. Broadley C.r. hampton J.P. hammond K.A. Payne Warwick hrI University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey University of Warwick Wellesbourne Warwick CV35 9EF UKKey

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Molecular Plant 2019年第6期12卷 833-846页

作者： Beatriz Lagunas Mingkee Achom roxanna Bonyadi-Pour Alonso J.Pardal Bethany L.richmond Chrysi Sergaki Saul Vazquez Patrick Schafer Sascha Ott John hammond Miriam L.Gifford School of Life Sciences University of Warwick Coventry CV4 7AL UK Department of Computer Science University of Warwick Coventry CV4 7AL UK Gateway Building Sutton Bonington Campus University of Nottingham Sutton Bonington LE12 5RD UK School of Agriculture Policy and Development University of Reading Reading RG6 6AH UK Southern Cross Plant Science Southern Cross University Lismore NSW 2480 Australia

Understanding how plants respond to nitrogen in their environment is crucial for determining how they use it and how the nitrogen use affects other processes related to plant growth and development. Under nitrogen limitation the activity and affinity of uptake systems is increased in roots, and lateral root formation is regulated in order to adapt to low nitrogen levels and scavenge from the soil. Plants in the legume family can form associations with rhizobial nitrogen-fixing bacteria, and this association is tightly regulated by nitrogen levels. The effect of nitrogen on nodulation has been extensively investigated, but the effects of nodulation on plant nitrogen responses remain largely unclear. In this study, we integrated molecular and phenotypic data in the legume Medicago truncatula and determined that genes controlling nitrogen influx are differently expressed depending on whether plants are mock or rhizobia inoculated. We found that a functional autoregulation of nodulation pathway is required for roots to perceive, take up, and mobilize nitrogen as well as for normal root development. Our results together revealed that autoregulation of nodulation, root development, and the location of nitrogen are processes balanced by the whole plant system as part of a resource-partitioning mechanism.

关键词： Nitrogen transport Medicago root system ar.h.tecture transcriptomics autoregulation of nodulation rhizobia

The next detectors for gravitational wave astronomy

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Science China(Physics,Mechanics & Astronomy) 2015年第12期58卷 91-124页

作者： BLAIr David JU Li ZhAO ChunNong WEN LinQing MIAO haiXing CAI rongGen GAO Jiangrui LIN XueChun LIU Dong WU Ling-An ZhU Zonghong hammond Giles PAIK ho Jung FAFONE Viviana rOCChI Alessio BLAIr Carl MA YiQiu QIN JiaYi PAGE Michael School of Physics The University of Western Australia School of Physics and Astronomy University of Birmingham State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences The School of Physics & Electronic Engineering Shanxi University Laboratory of All-Solid-State Light Sources Institute of Semiconductors Chinese Academy of Science State Key Laboratroy of Modern Optical Instrumentation Department of Optical Engineering Zhejiang University Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Gravitational Wave and Cosmology Laboratory Department of Astronomy Beijing Normal University School of Physics and Astronomy SUPA University of Glasgow Department of Physics University of Maryland College Park University of rome Tor Vergata INFN roma Tor Vergata

This paper focuses on the next detectors for gravitational wave astronomy which will be required after the current ground based detectors have completed their initial observations, and probably achieved the first direct detection of gravitational waves. The next detectors will need to have greater sensitivity, while also enabling the world array of detectors to have improved angular resolution to allow localisation of signal sources. Sect. 1 of this paper begins by reviewing proposals for the next ground based detectors,and presents an analysis of the sensitivity of an 8 km armlength detector, which is proposed as a safe and cost-effective means to attain a 4-fold improvement in sensitivity. The scientific benefits of creating a pair of such detectors in China and Australia is emphasised. Sect. 2 of this paper discusses the high performance suspension systems for test masses that will be an essential component for future detectors, while sect. 3 discusses solutions to the problem of Newtonian noise which arise from fluctuations in gravity gradient forces acting on test masses. Such gravitational perturbations cannot be shielded, and set limits to low frequency sensitivity unless measured and suppressed. Sects. 4 and 5 address critical operational technologies that will be ongoing issues in future detectors. Sect. 4 addresses the design of thermal compensation systems needed in all high optical power interferometers operating at room temperature. Parametric instability control is addressed in sect. 5. Only recently proven to occur in Advanced LIGO, parametric instability phenomenon brings both risks and opportunities for future detectors. The path to future enhancements of detectors will come from quantum measurement technologies. Sect. 6 focuses on the use of optomechanical devices for obtaining enhanced sensitivity, while sect. 7 reviews a range of quantum measurement options.

关键词： future gravitational wave detectors opto-mechanics quantum limit

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与思想家交谈

Spectroscopic studies of fuel recycling and impurity behaviors in the divertor region of Wendelstein 7-X

2016年

作者：（美）寒哲（L.James hammond）

本书引导您进入哲学、文学、伦理、宗教、心理学等领域，向您介绍各领域的经典作家及其思想。主要内容包括:哲学与生活、僵死而空洞的当代哲学、哲学的生命力所在、“是什么”和“应该是什么”等。

ISBN: (数字)9787515407005

ISBN: (纸本)9787515407005

关键词：通俗读物哲学思想世界

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Plasma Science and Technology 2019年第10期21卷 17-27页

作者： Yanling WEI Erhui WANG Yunfeng LIANG Southwestern Institute of Physics Forschungszentrum Jülich Gmbh Institut für Energie-und Klimaforschung—PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC) Max Planck Institute for Plasma Physics Australian National University

The first divertor operation phase (OP1.2a) was carried out on Wendelstein 7-X in the second half of 2017. Fuel recycling and impurity behaviors in the divertor region were investigated by employing a newly built ultraviolet–visible–near infrared overview spectroscopy system. The characteristic spectral lines of the working gases (hydrogen and helium), intrinsic impurities (carbon, oxygen and iron), and seeded impurities (neon and nitrogen) were identified and analyzed. The divertor electron temperature and density were measured using he I (667.8, 706.5, and 728.1 nm) line intensity ratios. The hα(656.3 nm), he I (587.6 nm), C II (514.5 nm), and O I (777.2 nm) emissions were investigated over a wide range of operating conditions. The results showed that fuel and impurity emissions in the divertor region exhibit a strong dependence on magnetic topology and plasma conditions. The levels of hα, he I, C II, and O I emissions are all reduced moving from the standard configuration to the high mirror configuration, and even fur.h.r reduced for the high iota configuration, which is associated with decreasing connection length in these island divertor configurations. The h/he influx ratio shows that the plasma is a mixture of helium and hydrogen. The neutral and impurity influxes from the divertor target tend to increase with increasing divertor electron temperature.

关键词： spectroscopy diagnostic fuel recycling impurity

发作后血氨水平作为惊厥性癫痫发作的生物标志物:一项前瞻性研究

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癫痫杂志 2017年第4期3卷 348-353页

作者： Albadareen r Gronseth G Landazuri P he J hammond N Uysal U 吴梦倩慕洁

有报道指出全面性惊厥性癫痫发作(Generalized convulsive seizures,GCS)后出现短暂性高血氨症(Transient hyperammonemia,ThA),没有足够的证据证实与癫痫的关系。文章的目的是确定发作后ThA是否可以区分不同类型的发作,如使用视频脑电... 详细信息

有报道指出全面性惊厥性癫痫发作(Generalized convulsive seizures,GCS)后出现短暂性高血氨症(Transient hyperammonemia,ThA),没有足够的证据证实与癫痫的关系。文章的目的是确定发作后ThA是否可以区分不同类型的发作,如使用视频脑电图(VEEG)监测确认脑电变化。在前瞻性队列中,筛选了所有进入癫痫监测单元并同意接受研究的成年患者(>18岁)。血氨的基础值以及在发作(所有患者)的60 min内、发作后24 h(只要有可能)的血氨水平均被检测。根据VEEG,将患者进行分组,分别为GCS、心因性惊厥性非痫性发作(Psychogenic nonepileptic seizures with convulsions,PNES-C)或局灶性癫痫发作(Focal seizures,FS)。使用描述性统计和参数/非参数方法分析数据。纳入患者78例,13例为GCS、8例为FS、9例为PNES-C。这些组在性别(P=0.04)和血氨基础值(P=0.02)方面是不同的,但年龄无差异。三组之间发作后血氨水平较血氨基础值的变化差异有统计学意义(P=0.004)。区分GCS与其他组差异的发作后血氨水平rOC曲线下面积为0.88[95%CI(0.69,0.96)],表明检测血氨水平是一种很好的用来区分GCS与其他发作的试验。血氨水平≥80μmol/L可以准确为80%的患者分类(灵敏度53.9%,特异性100%)。VEEG监测为ThA与GCS癫痫发作之间的关联提供了客观证据,并为今后关于确定发作后血氨水平作为GCS的廉价诊断试验作用的研究奠定了基础。

关键词：发作后高氨血症血氨惊厥性癫痫发作非痫性发作灵敏度和特异性