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ITPK1 is an InsP_(6)/ADP phosphotransferase that controls phosphate signaling in Arabidopsis.

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Molecular Plant 2021年第11期14卷 1864-1880页

作者： Esther Riemer Danye Qiu Debabrata Laha Robert K.harmel Philipp Gaugler Verena Gaugler Michael Frei Mohammad-Reza hajirezaei Nargis Parvin Laha Lukas Krusenbaum Robin Schneider Adolfo Saiardi Dorothea Fiedler h.nning j.jessen Gabriel Schaaf Ricardo F.h.Giehl Department of Plant Nutrition Institute of Crop Science and Resource ConservationRheinische Friedrich-Wilhelms-Universitat Bonn53115 BonnGermany Department of Chemistry and Pharmacy and CIBSS-Centre for Integrative Biological Signalling Studies Albert-Ludwigs University Freiburg79104 FreiburgGermany Medical Research Council Laboratory for Molecular Cell Biology(MRC-LMCB) University College LondonLondon WC1E 6BTUK Department of Biochemistry Indian Institute of ScienceBengaluruKarnataka 560012India Leibniz-Forschungsinstitut fur Molekulare Pharmakologie 13125 BerlinGermany Department of Chemistry Humboldt Universitat zu Berlin12489 BerlinGermany Institute of Agronomy and Crop Physiology Justus-Liebig University Giessen35392 GiessenGermany Department of Physiology&Cell Biology Leibniz-lnstitute of Plant Genetics and Crop Plant Research06466 GaterslebenGermany

In plants, phosphate (Pi) homeostasis is regulated by the interaction of PhR transcription factors with stand-alone SPX proteins, which act as sensors for inositol pyrophosphates. here, we combined different methods to obtain a comprehensive picture of how inositol (pyro)phosphate metabolism is regulated by Pi and dependent on the inositol phosphate kinase ITPK1. We found that inositol pyrophosphates are more responsive to Pi than lower inositol phosphates, a response conserved across kingdoms. With CE-ESI-MS we could separate different InsP7 isomers in Arabidopsis and rice, and identify 4/6-InsP7 and a PP-InsP4 isomer hitherto not reported in plants. We found that the inositol pyrophosphates 1/3-InsP7, 5-InsP7 and InsP8 increase severalfold in shoots after Pi resupply and that tissue-specific accumulation of inositol pyrophosphates relies on ITPK1 activities and MRP5-dependent InsP6 compartmentalization. Notably, ITPK1 is critical for Pi-dependent 5-InsP7 and InsP8 synthesis in planta and its activity regulates Pi starvation responses in a PhR-dependent manner. Furthermore, we demonstrate that ITPK1-mediated conversion of InsP6 to 5-InsP7 requires high ATP concentrations and that Arabidopsis ITPK1 has an ADP phosphotransferase activity to dephosphorylate specifically 5-InsP7 under low ATP. Collectively, our study provides deeper insights into Pi-dependent changes in nutritional and energetic states with the synthesis of regulatory inositol pyrophosphates.

关键词： diphosphoinositol pentakisphosphate kinase inositol 1,3,4-trisphosphate 5/6-kinase 1 inositol phosphates inositol pyrophosphates phosphate homeostasis phosphate signaling

Male reproductive suppression： not a social affair

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Current Zoology 2017年第5期63卷 573-579页

作者： Z. Valentina ZlZZRI Andrea jessen joris M. KOENE Department of Ecological Science--Animal Ecology VU University Amsterdam De Boelelaan 1085 1081 HVAmsterdam The Netherlands

In the animal kingdom there are countless strategies via which males optimize their reproductivesuccess when faced with male-male competition. These male strategies typically fall into two maincategories： pre- and post-copulatory competition. Within these 2 categories, a set of behaviors,referred to as reproductive suppression, is known to cause inhibition of reproductive physiologyand/or reproductive behavior in an otherwise fertile individual. What becomes evident when con-sidering examples of reproductive suppression is that these strategies conventionally encompassreproductive interference strategies that occur between members of a hierarchical social ***, mechanisms aimed at impairing a competitor＇s reproductive output are also present innon-social animals. Yet, current thinking emphasizes the importance of sociality as the primarydriving force of reproductive suppression. Therefore, the question arises as to whether there is anactual difference between reproductive suppression strategies in social animals and equivalentpre-copulatory competition strategies in non-social animals. In this perspective paper we explore abroad taxonomic range of species whose individuals do not repeatedly interact with the same indi-viduals in networks and yet, depress the fitness of rivals. Examples like alteration of male repro-ductive physiology, female mimicry, rival spermatophore destruction, and cementing the rival＇sgenital region in non-social animals, highlight that male pre-copulatory reproductive suppressionand male pre-copulatory competition overlap. Finally, we highlight that a distinction between malereproductive interference in animals with and without a social hierarchy might obscure importantsimilarities and does not help to elucidate why different proximate mechanisms evolved. We there-fore emphasize that male reproductive suppression need not be restricted to social animals.

关键词： indirect sperm transfer, offensive strategies, male pre-copulatory competition, male reproductive suppression, repro-ductive strategies.

The molecular profile of nerve repair: humans mirror rodents

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Neural Regeneration Research 2021年第7期16卷 1440-1441页

作者： Matthew B.Wilcox Kristjan R.jessen Tom j.Quick james B.Phillips Peripheral Nerve Injury Research Unit Royal National Orthopaedic HospitalStanmoreUK Department of Pharmacology UCL School of PharmacyUniversity College LondonLondon WC1N 1AXUK UCL Centre for Nerve Engineering University College LondonLondonUK Department of Cell and Developmental Biology University College LondonLondonUK

Peripheral nerve injuries(PNI)are common following blunt or penetrating trauma and can lead to disability and chronic pain in affected individuals,with limited options available to promote regeneration and functional *** animal models,it is known that the regenerative capacity of the peripheral nervous system(PNS)is heavily dependent upon the remarkable ability of Schwann cells to undergo a phenotypic shift from a supportive/myelinating/maintaining phenotype to one that encourages neural regeneration.

关键词： injuries mirror neural

Vasectomy by epithelial curettage without suture or cautery： a pilot study in humans

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Asian journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： john K. Amory john W. jessen Charles Muller Richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

Curettage of the epithelium of the vas deferens might be a safe and effective method of male sterilization. We conducted a pilot study of vasectomy by epithelial curettage with a novel microcurette called the Vas-X in 12 normal men requesting elective sterilization. Seminal fluid analysis was obtained monthly after the procedure for 6 months. Pain was assessed by questionnaire. Three months after the procedure, all men attained sperm concentrations of less than 0.2 million sperm per mL, and seven were azoospermic. Post-procedural pain was minimal. Nine men ultimately achieved and maintained azoospermia; however, 4 to 6 months after the procedure, sperm concentrations increased in three of the 12 subjects, necessitating repeat vasectomy. Microscopic examination of the vas deferens from these failures revealed re-canalization. Vasectomy by epithelial curettage can result in effective sterilization; however, 1/4 of the subjects were not effectively sterilized by the procedure due to re-canalization of the vas deferens. Epithelial curettage will require further refinement to determine if it is a viable form of vasectomy.

关键词： male contraception male sterilization re-canalization spermatogenesis vas deferens vasectomy failure

EU-China Partenariat 2006: Tailor-made Opportunities for SMEs of EU and China

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China's Foreign Trade 2006年第9期000卷 16-17页

作者： Franz jessen Minister Counsellor

2006 EU-China Partenariat 2006, the large-scale business-to-business event which will link almost one thousand European and Chinese companies is indeed a highly appropriate way to further enhance the already excellent relations between the EU and China moreover as this is the very year that we are celebrating 30 years of EU-China diplomatic ties. Since the establishment of diplomatic relations in 1975, cooperation between the EU and China has continuously

关键词： 2006年中国欧盟中小企业商机对外经济

Quality assessment of graphene： Continuity, uniformity, and accuracy of mobility measurements

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Nano Research 2017年第10期10卷 3596-3605页

作者： David M. A. Mackenzie jonas D. Buron Patrick R. Whelan josé M. Carida Martin Bjergfelt Bironq Luo Abhay Shivayogimath Anne L. Smitshuysen joachim D. Thomsen Timothy j. Booth Lene Gammelgaard johanna Zultak Bjarke S. jessen Peter Boggild Dirch h. Petersen Department of Micro- and Nanotechnology Technical University of Denmark Orsteds Plads 345 B Kongens Lyngby 2800 Denmark Center for Nanostructured Graphene (CNG) Technical University of Denmark Kongens Lyngby 2800 Denmark

With the increasing availability of large-area graphene, the ability to rapidly and accurately assess the quality of the electrical properties has become critically important. For practical applications, spatial variability in carrier density and carrier mobility must be controlled and minimized. We present a simple framework for assessing the quality and homogeneity of large-area graphene devices. The field effect in both exfoliated graphene devices encapsulated in hexagonal boron nitride and chemical vapor-deposited （CVD） devices was measured in dual current-voltage configurations and used to derive a single, gate-dependent effective shape factor, t, for each device, β is a sensitive indicator of spatial homogeneity that can be obtained from samples of arbitrary shape. All 50 devices investigated in this study show a variation （up to tenfold） in β as a function of the gate bias. Finite element simulations suggest that spatial doping inhomogeneity, rather than mobility inhomogeneity, is the primary cause of the gate dependence of β, and that measurable variations of β can be caused by doping variations as small as 10^10 cm^-2. Our results suggest that local variations in the position of the Dirac point alter the current flow and thus the effective sample shape as a function of the gate bias. We also found that such variations lead to systematic errors in carrier mobility calculations, which can be revealed by inspecting the corresponding β factor.

关键词： chemical vapor-deposited (CVD) graphene doping inhomogeneity electrical measurements van der Pauw hBN-encapsulated graphene finite element simulations Raman mapping

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AXI排除隐藏的焊点缺陷

电子电路与贴装 2006年第6期 66-68页

作者： jeremy jessen

Lamniographic自动X射线检查（AXI）可以应用于焊点检测，包括对隐藏在面积阵列封装下面的焊点进行检测。AXI也能在生产期间发现大多数的焊接缺陷，因而非常适于分析面积阵列封装上的焊点。

关键词：焊点缺陷 AXI 隐藏焊点检测阵列封装 X射线检查焊接缺陷生产期

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为生产加速的移动式机器人

现代制造 2018年第31期 28-28,30页

作者： Anders jessen 不详

一家位于挪威的新型智能化工厂通过利用许多由系统集成商开发和生产的移动式机器人实现了高灵活性的智能化生产。这家工厂内,拥有自己工作站或者工作间的数十台工业机器人承担着不同生产加工中的不同工作步骤,在生产过程中为了实现现代... 详细信息

一家位于挪威的新型智能化工厂通过利用许多由系统集成商开发和生产的移动式机器人实现了高灵活性的智能化生产。这家工厂内,拥有自己工作站或者工作间的数十台工业机器人承担着不同生产加工中的不同工作步骤,在生产过程中为了实现现代化智能工厂对高效率、高安全性和舒适性的要求,作为系统集成商的Intek工程技术公司就必须将这些机器人工作间、工作站有机的联系到一起,构成一个整体系统。

关键词：移动式机器人智能化生产系统集成商工业机器人高灵活性生产加工智能工厂生产过程

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超强半导体

科技纵览 2021年第4期 36-42页

作者： Gmggh.jessen 不详

在本刊2002年5月刊中,已故的莱斯特·F.伊斯曼(Lester ***-man)和乌梅什.K.米什拉(Umesh ***)谈到了当时功率半导体界的一项大胆技术:氨化家(GaN)。对于强大耐用的射频放大器在当时新兴的宽带无线网络、雷达以及电网功率切换应用中的使... 详细信息

在本刊2002年5月刊中,已故的莱斯特·F.伊斯曼(Lester ***-man)和乌梅什.K.米什拉(Umesh ***)谈到了当时功率半导体界的一项大胆技术:氨化家(GaN)。对于强大耐用的射频放大器在当时新兴的宽带无线网络、雷达以及电网功率切换应用中的使用前景,他们表达了乐观的看法。他们称氮化嫁器件为“迄今为止最坚固耐用的晶体管”伊斯曼和米什拉是对的。氮化家的宽带隙(使束缚电子自由断裂并有助于传导的能量)和其他性质让我们能够利用这种材料承受高电场的能力,制造性能空前的器件。

关键词：功率半导体射频放大器宽带无线网络束缚电子高电场氮化嫁宽带隙伊斯曼