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Genetic diversity and differentiation follow secondary succession in a multi-species study on woody plants from subtropical China

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Journal of Plant Ecology 2017年第1期10卷 213-221页

作者： Christoph Z.hahn Stefan G.Michalski Markus Fischer Walter Durka Department of Community Ecology(BZF) Helmholtz Centre for Environmental Research—UFZTheodor-Lieser-Straße 4D-06120 HalleGermany Institute of Plant Sciences University of BernAltenbergrain 21CH-3013 BernSwitzerland German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Pl.5E04103 LeipzigGermany

Aims Species diversity and genetic diversity may be affected in parallel by similar environmental ***,genetic diversity may also be affected independently by habitat *** aim at disentangling relationships between genetic diversity,species diversity and habitat characteristics of woody species in subtropical *** We studied 11 dominant tree and shrub species in 27 plots in Gutianshan,China,and assessed their genetic diversity(A_(r))and population differentiation(F′_(ST))with microsatellite *** tested if Ar and population specific F′_(ST) were correlated to local species diversity and plot ***-model inference and model averaging were used to determine the relative importance of each ***,we tested for isolation-by-distance(IBD)and isolation-by-elevation by regressing pairwise F′_(ST) against pairwise spatial and elevational *** Findings Genetic diversity was not related to species diversity for any of the study ***,our results do not support joint effects of habitat characteristics on these two levels of ***,genetic diversity in two understory shrubs,Rhododendron simsii and Vaccinium carlesii,was affected by plot age with decreasing genetic diversity in successionally older *** differentiation increased with plot age in *** and Lithocarpus *** shows that succession can reduce genetic diversity within,and increase genetic diversity between ***,we found four cases of IBD and two cases of *** former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological *** patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.

关键词： Allelic richness population differentiation habitat characteristics gene flow species-genetic diversity correlation SGDC

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Smart Proactive Caching Scheme for Fast Authenticated Handoff in Wireless LAN

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Journal of Computer Science & Technology 2007年第3期22卷 476-480页

作者： Sin-Kyu Kim Jae-Woo Choi Dae-Hun Nyang Gene-Beck hahn Joo-Seok Song Electronics Telecommunications Research Institute Daejeon Korea Graduate School of Information Technology and Telecommunications Inha University IncheonKorea Mobile Communication Technology Research Lab LG Electronics AnyangKorea Department of Computer Science Yonsei University SeoulKorea

Handoff in IEEE 802.11 requires the repeated authentication and key exchange procedures, which will make the provision of seamless services in wireless LAN more difficult. To reduce the overhead, the proactive caching schemes have been proposed. However, they require too many control packets delivering the security context information to neighbor access points. Our contribution＇ is made in two-fold： one is a significant decrease in the number of control packets for proactive caching and the other is a superior cache replacement algorithm.

关键词： wireless local area network (LAN) security authentication simulation

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Lightweight in Automotive Components by Forming Technology

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Automotive Innovation 2020年第3期3卷 195-209页

作者： Stephan Rosenthal Fabian Maaß Mike Kamaliev Marlon hahn Soeren Gies A.Erman Tekkaya Institute of Forming Technology and Lightweight Components(IUL) TU Dortmund University44227 DortmundGermany

Lightweight design is one of the current key drivers to reduce the energy consumption of *** methodologies for lightweight components,strategies utilizing materials with favorable specific properties and hybrid materials are used to increase the performance of parts for automotive *** this paper,various forming processes to produce light parts are *** lightweight design is discussed,covering the manufacturing processes to produce hybrid components like fiber-metal,polymer-metal and metal-metal composites,which can be used in subsequent deep drawing or combined forming *** to increasing the specific strength and stiffness with thermomechanical forming processes as well as the in situ control of the microstructure of such components are *** lightweight design discusses possibilities to plastically form high-strength or high-performance materials like magnesium or titanium in sheet,profile and tube forming *** join those materials and/or dissimilar materials,new joining by forming technologies are *** economically produce lightweight parts with gears or functional elements,incremental sheet-bulk metal forming is *** an important part property,the damage evolution during the forming operations will be discussed to enable even lighter parts through a more reliable *** methods for predicting and tailoring the mechanical properties like strength and residual stresses will be *** possibilities of system lightweight design with forming technologies are presented.A combination of additive manufacturing and forming to produce highly complex parts with integrated functions will be *** integration of functions by a hot extrusion process for the manufacturing of shape memory alloys is *** in-depth understanding of the newly developed processes,methodologies and effects allows for a more accurate dimen-sioning of *** facilitates a reduction in th

关键词： Forming technology Lightweight design Energy efficiency Manufacturing processes

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Spatial heterogeneity of flesh-cell osmotic potential in sweet cherry affects partitioning of absorbed water

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Horticulture Research 2020年第1期7卷 2104-2113页

作者： Eckhard Grimm Daniel Pflugfelder Jan hahn Moritz Jonathan Schmidt Hendrik Dieckmann Moritz Knoche Institut für Gartenbauliche Produktionssysteme Leibniz Universität HannoverAbteilung ObstbauHerrenhäuser Straße 2D-30419 HannoverGermany Forschungszentrum Jülich IBG-2:PflanzenwissenschaftenWilhelm-Johnen-StraßeD-52428 JülichGermany Laser Zentrum Hannover e.V. Hollerithallee 8D-30419 HannoverGermany

A fleshy fruit is commonly assumed to resemble a thin-walled pressure vessel containing a homogenous carbohydrate *** sweet cherry(Prunus avium L.)as a model system,we investigate how local differences in cell water potential affect H2O and D2O(heavy water)*** partitioning of H2O and D2O was mapped nondestructively using magnetic resonance imaging(MRI).The change in size of mesocarp cells due to water movement was monitored by optical coherence tomography(OCT,non-destructive).Osmotic potential was mapped using microosmometry(destructive).Virtual sections through the fruit revealed that the H2O distribution followed a net pattern in the outer mesocarp and a radial pattern in the inner *** patterns align with the disposition of the vascular bundles.D2O uptake through the skin paralleled the acropetal gradient in cell osmotic potential gradient(from less negative to more negative).Cells in the vicinity of a vascular bundle were of more negative osmotic potential than cells more distant from a vascular *** revealed net H2O uptake was the result of some cells loosing volume and other cells increasing volume.H2O and D2O partitioning following uptake is non-uniform and related to the spatial heterogeneity in the osmotic potential of mesocarp cells.

关键词： potential Spatial bundle

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Intrahepatic cholangiocarcinoma: Introducing the preoperative prediction score based on preoperative imaging

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Hepatobiliary & Pancreatic Diseases International 2021年第3期20卷 262-270页

作者： Fabian Bartsch Felix hahn Lukas Müller Janine Baumgart Maria Hoppe-Lotichius Roman Kloeckner Hauke Lang Department of General Visceral and Transplant SurgeryUniversity Medical Center of the Johannes Gutenberg-University MainzLangenbeckst155131 MainzGermany Department of Diagnostic and Interventional Radiology University Medical Center of the Johannes Gutenberg-University MainzLangenbeckst155131 MainzGermany

Background: Intrahepatic cholangiocarcinoma(ICC) still has a poor long-term outcome, even after complete resection. We investigated different parameters gathered in preoperative imaging and analyzed their influence on resectability, recurrence, and survival. Methods: All patients who underwent exploration due to ICC between January 2008 and June 2018 were analyzed retrospectively. Kaplan-Meier model, log-rank test and Cox regression were used. Results: Out of 184 patients, 135(73.4%) underwent curative intended resection. Median overall survival(OS) was 22.2 months with a consecutive 1-, 3-and 5-year OS of 73%, 29%, and 17%. Median recurrencefree survival(RFS) was 9.3 months with a consecutive 1-, 3-and 5-year RFS of 36%, 15%, and 11%. Site of tumor, parenchymal localization, tumor configuration/dissemination, and estimated tumor volume had significant influence on resectability. Univariate analyses showed that site of tumor, tumor configuration/dissemination, number of nodules, and estimated tumor volume had predictive values for OS and RFS. Together with tumor size the preoperative prediction(POP) score was created showing significance for OS and RFS(all P<0.001). In multivariate analysis, POP score(HR=1.779;95% CI: 1.26 8-2.4 95;P=0.001), T stage(HR=1.255;95% CI: 1.040-1.514;P=0.018) and N stage(HR=1.334;95% CI: 1.081-1.645;P=0.007) were the independent predictors for OS. For RFS, POP score(HR=1.733;95% CI: 1.30 0-2.311;P<0.0 01) and M stage(HR=3.036;95% CI: 1.376-6.697;P=0.006) were the independent predictors. Conclusions: The POP score showed to have a highly significant influence on OS and RFS. The score is easy to assess through preoperative imaging. For patients in the high risk group at least staging laparoscopy or preoperative chemotherapy should be evaluated, because they showed equal outcome compared to the irresectable group.

关键词： Intrahepatic cholangiocarcinoma Cholangiocarcinoma Liver surgery Preoperative imaging Survival

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Bioinspired urease-powered micromotor as an active oral drug delivery carrier in stomach

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Bioactive Materials 2022年第3期7卷 54-62页

作者： Hyunsik Choi Sang Hoon Jeong Tae Yeon Kim Jeeyoon Yi Sei Kwang hahn Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)77 Cheongam-roNam-guPohangGyeongbuk37673South Korea

Self-propelling micro-and nano-motors(MNMs)have been extensively investigated as an emerging oral drug delivery carrier for gastrointestinal(GI)tract ***,the propulsion of current MNMs reported so far is mostly based on the redox reaction of metals(such as Zn and Mg)with severe propulsion gas generation,remaining non-degradable residue in the GI ***,we develop a bioinspired enzyme-powered biopolymer micromotor mimicking the mucin penetrating behavior of Helicobacter pylori in the *** converts urea to ammonia and the subsequent increase of pH induces local gel-sol transition of the mucin layer facilitating the penetration into the stomach tissue *** successful fabrication of micromotors is confirmed by high-resolution transmission electron microscopy,electron energy loss spectroscopy,dynamic light scattering analysis,zeta-potential *** acidic condition,the immobilized urease can efficiently converted urea to ammonia,comparable with that of neutral condition because of the increase of surrounding pH during *** administration into the stomach,the micromotors show enhanced penetration and prolonged retention in the stomach for 24 ***,histological analysis shows that the micromotors are cleared within 3 days without causing any toxicity in the GI *** enhanced penetration and retention of the micromotors as an active oral delivery carrier in the stomach would be successfully harnessed for the treatment of various GI tract diseases.

关键词： Micro-and nanomotors Polydopamine Urease Oral delivery Stomach diseases

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Hybrid integration of 2D materials for on-chip nonlinear photonics

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Light(Advanced Manufacturing) 2023年第3期4卷 311-333页

作者： Vincent Pelgrin Hoon hahn Yoon Eric Cassan Zhipei Sun QTF Centre of Excellence Department of Electronics and NanoengineeringAalto UniversityP.O.Box 13500FI-00076 AaltoFinland UniversitéParis-Saclay CNRSCentre de Nanosciences et de Nanotechnologies91120PalaiseauFrance

Interests surrounding the development of on-chip nonlinear optical devices have been consistently growing in the past decades due to the tremendous applications,such as quantum photonics,all-optical communications,optical computing,on-chip metrology,and *** efficient on-chip nonlinear optical devices to meet the requirements of those applications brings the need for new directions to improve the existing photonic *** research has directed the field of on-chip nonlinear optics toward the hybrid integration of two-dimensional layered materials(such as graphene,transition metal dichalcogenides,and black phosphorous)with various integrated *** combination of well-known photonic chip design platforms(e.g.,silicon,silicon nitride)and different two-dimensional layered materials has opened the road for more versatile and efficient structures and devices,which has the great potential to unlock numerous new *** review discusses the modeling and characterization of different hybrid photonic integration structures with two-dimensional materials,highlights the current state of the art examples,and presents an outlook for future prospects.

关键词： Integrated photonics 2D materials Nanophotonic Nonlinear optics Quantum computation All-optical computing Spectroscopy Broadband light sources

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Magnetic Properties of Nanostructured Fe_(40)Ni_(38)Mo_(4)B_(l8)

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Chinese Physics Letters 1999年第3期16卷 211-213页

作者： LI Jian-gong SU Zhi-bin WEI Fu-lin YANG Zheng Horst hahn WANG Tian-min GE Shi-hui Department of Materials Science Lanzhou UniversityLanzhou 730000 Applied Magnetism Laboratory of the Education Ministry Lanzhou UniversityLanzhou 730000 Department of Materials Science Darmstadt University of Technology64287 DarmstadtGermany School of Science Beijing University of Aeronautics and AstronauticsBeijing 100083 Department of Physics Lanzhou UniversityLanzhou 730000

Nanostructured Fe_(40)Ni_(38)Mo_(4)B_(l8) prepared by crystallization technique has a microstructure of nanometer-sized fcc(Fe,Ni)solid solution crystallites embedded in a nanometer-thick amorphous *** nanostructured Fe_(40)Ni_(38)Mo_(4)B_(l8) obtained at 740K has the optimal soft magnetic *** maximal magnetic softening can be understood by considering the combination of the zero anisotropy and the lowest saturation magnetostriction.

关键词： softening microstructure magnetic

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HoLEP does not affect the overall sexual function of BPH patients： a prospective study

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Asian Journal of Andrology 2014年第6期16卷 873-877页

作者： Sung Hart Kim Hyung-Kook Yang hahn-Ey Lee Jae-Seung Paick Seung-June Oh Department of Urology Prostate Cancer Center National Cancer Center Goyang Korea Department of Epidemiology and Statistics and Cancer Policy Branch of National Cancer Control Research Institute National Cancer Center Goyang Korea Department of Urology Seoul National University Hospital Seoul Korea.

We aimed to prospectively evaluate the influence of holmium laser enucleation of the prostate （HoLEP） on the overall postoperative sexual function of benign prostatic hyperplasia （BPH） patients with lower urinary tract symptoms （LUTS） and to explore the relationship between sexual function and LUTS. From January 2010 to December 2011, sixty sexually active consecutive patients with BPH who underwent HoLEP were prospectively enrolled in the study. All patients filled out the Male Sexual Health Questionnaire （MSHQ） for evaluation of their overall sexual function and the International Prostatic Symptom Score （IPSS） for pre- and post-operative 6 months evaluation of their voiding symptoms. The LUTS and sexual function changes were statistically analyzed. The preoperative and 6 months postoperative status of the patients was compared using uroflowmetry and IPSS questionnaires. The analysis revealed significant improvements following HoLEP. Among the sub-domains of the MSHQ, postoperative sexual function, including erection, ejaculation, sexual satisfaction, anxiety or sexual desire, did not significantly change after HoLEP （P 〉 0.05）, whereas satisfaction scores decreased slightly due to retrograde ejaculation in 38 patients （63.3%）. Sexual satisfaction improved significantly and was correlated with the improvements of all LUTS and the quality-of-life （QoL） domains in IPSS after surgery （QoL; relative risk [RR]： -0.293; total symptoms, RR： -0.411; P 〈 0.05）. The nocturia score was associated with the erectile function score （odds ratio 0.318, P = 0.029）. The change in ejaculatory scores did not show significant association with IPSS scores. HoLEP did not influence overall sexual function, including erectile function. In addition, sexual satisfaction improved in proportion with the improvement of LUTS.

关键词： benign prostatic hyperplasia ejaculation erectile dysfunction lasers prostatectomy sex disorders

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Activation and dramatically increased cytolytic activity of tumor specific T lymphocytes after radio-frequency ablation in patients with hepatocellular carcinoma and colorectal liver metastases

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World Journal of Gastroenterology 2006年第23期12卷 3716-3721页

作者： Johannes Hansler Thaddaus Till Wissniowski Detlef Schuppan Astrid Witte Thomas Bernatik Eckhart Georg hahn Deike Strobel Department of Medicine 1 Friedrich Alexander University Erlangen NurembergGermany Experimental Hepatology and Ontology Nikolaus Fiebiger Center Friedrich AlexanderUniversity Erlangen Nuremberg Germany Division of Gastroenterology Beth IsraelDeaconess Medical Center Harvard Medical School Boston MAUnited States

AIM： To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation （RFA）. METHODS： Six Patients with liver metastases of colorectal cancer and 6 with hepatocellular carcinoma （HCC） underwent RFA. Blood was sampled before, 4 and 8 wk after RFA. Test antigens were autologous liver and tumor lysate obtained from each patient by biopsy. Peripheral T cell activation was assessed by an interferon gamma （IFNγ） secretion assay and flow cytometry. T cells were double-stained for CD4/CD8 and IFNγ to detect cytotoxic T cells. The ratio of IFNγ positive and IFNγ negative T cells was determined as the stimulation index （SI）. To assess cytolytic activity, T cells were co-incubated with human CaCo colorectal cancer and HepG2 HCC cells and release of cytosolic adenylate kinase was measured by a luciferase assay. RESULTS： Before RFA SI was 0.021 （±0.006） for CD4^＋ and 0.022 （± 0.004） for CD8^＋T cells against nonmalignant liver tissue and 0.018 （± 0.005） for CD4^＋ and 0.021 （± 0.004） for CD8^＋ cells against autologous tumor tissue. Four weeks after RFA SI against tumor tissue increased to 0.109 （± 0.005） for CD4＋ and 0.11 （± 0.012） for CD8＋ T cells against HCC, and to 0.115 （± 0.031） for CD4^＋ and 0.15 （± 0.02） for CD8^＋ cells for colorectal metastases （P 〈 0.0001）. No increased SI was observed with nonmalignant tumor tissue at all time points. Before RFA cytolytic activity against the respect（ve cancer cells was low with 2.62 （± 0.37） relative luminescence units （RLU）, but rose more than 100 fold 4 and 8 wk after RFA. Spontaneous release was 〈 2% of maximum release in all experiments. CONCLUSION： Patients with primary and secondary tumors of the liver show a significant tumor-specific cytotoxic T-cell stimulation with a dramatically increased tumor specific cytolytic activity of CD8^＋ T cells after RFA.

关键词： CD4 CD8 Cytotoxic Immune response Immunology Immunotherapy Interferon gamma T cells NK Therapeutic vaccination

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