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Differential modulation of crown allometry and stem growth at gap edges in five European tree species by drought conditions

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Forest Ecosystems 2024年第5期11卷 618-631页

作者： Luke Bohnhorst Peter Biber Torben Hilmers Enno Uhl hans Pretzsch Chair of Forest Growth and Yield Science TUM School of Life SciencesTechnical University of MunichHans-Carl-von-Carlowitz-Platz 285354FreisingGermany Bavarian State Institute of Forestry Hans-Carl-von-Carlowitz-Platz 185354FreisingGermany

Background In Central Europe,forests are increasingly affected by various disturbances,resulting in an increasing gap formation in the *** order to support goal-oriented management,more knowledge is required about the acclimation of the crown and its effects on the basal area growth of trees at the edge of a *** This work compared trees'growth and crown structure at the edge of a transient gap,with a gap size of more than 80m^(2),with trees in the stand that were at least 30m away from the gap.A total of 249 European beeches(Fagus sylvatica L.),Norway spruces(Picea abies ***),Scots pines(Pinus sylvestris L.),oaks(Quercus spp.;Quercus petraea(Matt.)Liebl.,Quercus robur L.),and silver firs(Abies alba Mill.)were examined on long-term experimental plots in southern *** crown measures were developed and calculated using high-resolution terrestrial laser scanning(TLiDAr)to capture the three-dimensional crown *** responses to edge conditions were measured based on tree *** linear mixed models,we predict the basal area increment of edge trees relative to trees in the stand under wet and dry soil moisture conditions after the gap *** We identified i)species-specific acclimation of the crown of edge trees after the gap formation,ii)under wet soil moisture conditions a growth increase of 25%–45%for beech,pine,and oak edge trees and growth losses of 5%–60%for spruce and fir and iii)coniferous tree species benefited from the edge position regarding their basal area increment under dry soil moisture conditions and deciduous tree species grew regardless of the soil moisture conditions at the edge of a *** Gaps have a species-specific effect on the habitus and growth of edge trees and can have both positive and negative impacts on silviculture.

关键词： Canopy gaps Disturbance Growth TLiDAr Drought stress Crown structure Acclimation

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Surveillance colonoscopy practice in Lynch syndrome in the Netherlands:A nationwide survey

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World journal of Gastroenterology 2007年第34期13卷 4658-4659页

作者： jan j Koornstra hans FA Vasen Department of Gastroenterology and Hepatology University Medical Centre Groningen University of Groningen Groningen The Netherlands The Netherlands Foundation for the Detection of Hereditary Tumors Department of Gastroenterology Leiden University Medical Centre Leiden The Netherlands

Lynch syndrome, or hereditary nonpolyposis colorectal cancer (HNPCC), is the most common genetic disorder predisposing to colorectal cancer. As regular colonoscopic surveillance has been shown to reduce the incidence of colorectal cancer, this strategy is recommended worldwide. recently, several advances in colonoscopic techniques have improved detection rates of neoplasia in Lynch syndrome. In this nationwide survey, we evaluated current surveillance colonoscopy practices for Lynch syndrome in the Netherlands and the extent to which advanced techniques have been adopted in routine clinical practice.

关键词： Lynch syndrome Hereditary nonpolyposiscolorectal cancer Colonoscopy Surveillance Chromoendoscopy

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Voxel-based analyses of magnetization transfer imaging of the brain in hepatic encephalopathy

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World journal of Gastroenterology 2009年第41期15卷 5157-5164页

作者： Falk r Miese hans-jrg Wittsack Gerald Kircheis Arne Holstein Christian Mathys Ulrich Mdder Mathias Cohnen Institute of radiology University Hospital Düsseldorf MNR Clinic Moorenstrasse 5 Düsseldorf 40225 Germany Department of Internal Medicine Division of Gastroenterology Hepatology and Infectious Diseases University Hospital Düsseldorf Moorenstrasse 5 Düsseldorf 40225 Germany

AIM: To evaluate the spatial distribution of cerebral abnormalities in cirrhotic subjects with and without hepatic encephalopathy (HE) found with magnetization transfer imaging (MTI).METHODS: Nineteen cirrhotic patients graded from neurologically normal to HE grade 2 and 18 healthy control subjects underwent magnetic resonance imaging. They gave institutional-review-board-approved written consent. Magnetization transfer ratio (MTr) maps were generated from MTI. We tested for significant differences compared to the control group using statistical non-parametric mapping (SnPM) for a voxelbased ***: The MTr of grey and white matter was lower in subjects with more severe HE. Changes were found in patients with cirrhosis without neurological defi cits in the basal ganglia and bilateral white matter. The loss in magnetization transfer increased in severity and spatial extent in patients with overt HE. Patients with HE grade 2 showed an MTr decrease in white and grey matter: the maximum loss of magnetization transfer effect was located in the basal ganglia [SnPM (pseudo-)t = 17.98, P = 0.0001].CONCLUSION: The distribution of MTr changes in HE points to an early involvement of basal ganglia and white matter in HE.

关键词： Brain Hepatic encephalopathy Magnetic resonance imaging Uver cirrhosis Magnetization transfer imaging

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Biologic Waste： Consistent Performance with an Alternating Field

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journal of Environmental Science and Engineering(B) 2017年第12期6卷 589-592页

作者： hans-jürgen Huber Industry Sales Development Chemicals Siemens AG Karlsruhe 76187 Germany

Biomass plants often struggle to capture flow measurements reliably. High amounts of dry solids and fats complicate the measurement with an MID （Magnetic-Inductive） flowmeter and make it susceptible to faults. To overcome this impediment, the waste water treatment plant in Innsbruck, Austria, relies on electromagnetic pulsed AC （Alternating Current） flowmeters. Compared to pulsed DC （Direct Current） devices, AC devices are able to build up magnetic fields that are ten times stronger. Equipped with this capability, the Sitrans Transmag 2 is able to guarantee a constant and also high measuring accuracy, zero point stability and signal strength regardless of impurities in the medium or fluctuations in the magnetic field.

关键词： Biomass wastewater treatment process instrumentation flow measurement pulsed AC meter pulsed DC meter Transmag 2.

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CHALLENGES PrOVIDING MULTIPLE ECOSYSTEM BENEFITS FOr SUSTAINABLE MANAGED SYSTEMS

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Frontiers of Agricultural Science and Engineering 2022年第2期9卷 170-176页

作者： hans LAMBErS Wen-Feng CONG School of Biological Sciences and Institute of Agriculture University of Western Australia35 Stirling HighwayPerthWA 6009Australia College of resources and Environmental Sciences Key Laboratory of Plant-Soil InteractionsMinistry of EducationNational Observation and Research Station of Agriculture Green Development(QuzhouHebei)China Agricultural UniversityBeijing 100193China

Since humans started practicing agriculture at the expense of natural forests,8000 years ago,they have affected atmospheric CO_(2) *** impact on atmospheric CH_(4) started about 5000 years ago,as result of the cultivation of paddy rice.A challenge of modern agricultural practices is to reverse the impact cropping has had on greenhouse gas emissions and the global *** is an increasing demand for agriculture to provide food security as well as a range of other ecosystem *** on ecosystem management,different practices may involve trade-offs and synergies,and these must be considered to work toward desirable management *** toward food security should not only focus on agricultural management practices,but also on strategies to reduce food waste,more socially-just distribution of resources,changes in lifestyle including decarbonization of the economy,as well as reducing human population growth.

关键词： crop diversification ecosystem services food security sustainable cropping systems

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Electromagnetic Fields and Calcium Signaling by the Voltage Dependent Anion Channel

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Open journal of Veterinary Medicine 2021年第1期11卷 57-86页

作者： Volker Ullrich hans-jürgen Apell Department of Biology University of Konstanz Konstanz Germany

Electromagnetic fields (EMFs) can interact with biological tissues exerting positive as well as negative effects on cell viability, but the underlying sensing and signaling mechanisms are largely unknown. So far in excitable cells EMF exposure was postulated to cause Ca2+ influx through voltage-dependent Ca channels (VDCC) leading to cell activation and an antioxidant response. Upon further activation oxidative stress causing DNA damage or cell death may follow. Here we report collected evidence from literature that voltage dependent anion channels (VDAC) located not only in the outer microsomal membrane but also in the cytoplasmic membrane convert to Ca2+ conducting channels of varying capacities upon subtle changes of the applied EMF even in non-excitable cells like erythrocytes. Thus, VDAC can be targeted by external EMF in both types of membranes to release Carmal;">2+ into the cytosol. The role of frequency, pulse modulation or polarization remains to be investigated in suitable cellular models. VDACs are associated with several other proteins, among which the 18 kDa translocator (TSPO) is of specific interest since it was characterized as the central benzodiazepine receptor in neurons. Exhibiting structural similarities with magnetoreceptors we propose that TSPO could sense the magnetic component of the EMF and thus together with VDAC could trigger physiological as well as pathological cellular responses. Pulsed EMFs in the frequency range of the brain-wave communication network may explain psychic disturbances of electromagnetic hypersensitive persons. An important support is

关键词： Ca Signaling VDAC Benzodiazepine receptor Mechanistic Concept Pulsed EMFs Electromagnetic Hypersensitivity TSPO Erythrocytes NADH-Oxidase Apoptosis Magnetosensor Membrane Potential Oxidative Stress Brain Signaling Autism

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Comparison of Leptosphaeria biglobosa-induced and chemically induced systemic resistance to *** in Brassica napus

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Chinese Science Bulletin 2007年第8期52卷 1053-1062页

作者： LIU ShengYi LIU renHu Akinwunmi O. LATUNDE-DADA hans j. COOLS Simon j. FOSTEr HUANG Yongju Bruce D. L. FITT rothamsted research Harpenden Hertfordshire AL5 2JQ UK Key Lab of Genetic Improvement of Oil Crops Chinese Ministry0f Agriculture CAAS Oil Crops Research Institute Wuhan 430062 China Zhejiang Academy of Agricultural Sciences Hangzhou 310021 China

Brassica napus(***)seedlings pre-treated with ascospores of Leptosphaeria biglobosa or foliar sprays of either acibenzolar-S-methyl(ASM)or menadione sodium bisulphite(MSB)were chal- lenge inoculated with *** ascospores and assessed for phoma leaf spot development and tissue morphology and gene expression responses to *** of increase in phoma leaf spot area 8―21 d after challenge inoculation were significantly greater on water pre-treated plants than on plants pre-treated with ***,ASM or MSB on both pre-treated leaves(local effect)and younger leaves without pre-treatment(systemic effect).Ninety-six h after challenge inoculation,the invasive hyphae of *** were encircled by rings of necrotic mesophyll cells on leaves pre-treated with L. biglobosa,ASM or MSB but not those pre-treated with *** of transcript levels of genes commonly used as markers of the major defence signalling pathways(PDF1.2,Pr-1,NPr1,APX, CHB4)0–96 h after *** challenge inoculation showed expression patterns indicating prefer- ential activation of the jasmonate/ethylene pathway and involved induction of NPr1 locally and sys- temically in leaves of plants pre-treated with *** ascospores.

关键词：油菜黑胫病抗性黑胫病弱毒种诱导途径比较化学诱导

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Conception of a new 4-quadrant hydrogen compressed air energy storage power plant with an integrated electrolyzer

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Energy reviews 2024年第3期3卷 92-101页

作者： hans-Peter Beck Ann-Kathrin Klaas Christoph Klaas research Center Energy Storage Technologies Clausthal University of TechnologyAm Stollen 19A38640GoslarGermany Institute of Electrical Power Engineering and Energy Systems Clausthal University of TechnologyLeibnizstraße 2838678Clausthal-ZellerfeldGermany

A hydrogen compressed air energy storage power plant with an integrated electrolyzer is ideal for large-scale,long-term energy storage because of the emission-free operation and the possibility to offer multiple ancillary services on the German energy *** paper defines analyzes such a storage concept and conducts an extensive comparison with four additional storage concepts based on various *** results show that the combination of storing compressed air and hydrogen offers a higher efficiency than storing only hydrogen and lower specific investment costs than storing only compressed *** result is confirmed with analysis of the optimal sizing of each power plant component for simultaneous participation on multiple energy markets with a linear optimization dispatch *** hydrogen compressed air energy storage(HCAES)power plant can utilize more revenue possibilities than a hydrogen energy storage because of the higher round-trip efficiency and the combination of the air compressor and the integrated electrolyzer during charging *** integration of the electrolyzer,however,offers a couple of challenges itself because of the highly flexible operation mode.A new concept for the controllable 24-pulse diode-thyristor rectifier of the electrolyzer is presented,that uses mostly common components while offering little to no grid harmonics and a long *** flexible integrated electrolyzer allows for the 4-quadrant operation of the storage power plant.

关键词： Long-term energy storage Hydrogen energy storage Compressed air energy storage Mixed-integer linear programming Electrolyzer 24-Pulse thyristor rectifier

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Factors influencing the adoption of physical soil and water conservation practices in the Ethiopian highlands

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International Soil and Water Conservation research 2018年第1期6卷 23-30页

作者： Asnake Mekuriaw Andreas Heinimann Gete Zeleke hans Hurni Department of Geography and Environmental Studies Addis Ababa UniversityPO Box 1739Bahir DarEthiopia Center for Development and Environment University of BernSwitzerland Water and Land resource Center Addis AbabaEthiopia

Soil and Water Conservation (SWC) structures have been constructed on cultivated land for nearly 40 years to reduce soil loss and improve crop yields and people's livelihoods in the Ethiopian highlands. However, the success of this huge effort has been mixed, and the main constraints have not been investigated in detail. This study was undertaken to identify the factors determining the adoption of SWC structures in the Ethiopian Highlands. Case study areas were selected from high-potential and low-potential areas. Data were collected from 269 farmers using face-to-face interviews, and through focus group discussions, key informant interviews and field observations. Binary logistic regression model and descriptive statistics were used to analyze the data. The result showed that the majority (87%) of the farmers interviewed were using SWC structures. regionally, nearly all farmers in the low-potential areas and 56% of farmers in the high-potential areas constructed and were maintaining the structures properly. This disparity is due to the fact that in the low-potential areas there have been strong governmental involvement and technical and financial support, and hence the farmers there have a better understanding of the multiple uses of physical SWC structures than do farmers in the high-potential areas. In addition, off-farm activities and free grazing plays a substantial role. We can conclude that clear understanding of the benefits of SWC structures by farmers, active involvement and technical support from the government, and genuine participation of farmers in SWC practices were found to be main factors in the adoption of SWC measures.

关键词： SWC structures Ethiopian highlands High-potential area Low-potential area Adoption

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Climate change projections for the Middle EasteNorth Africa domain with COSMO-CLM at different spatial resolutions

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Advances in Climate Change research 2018年第1期9卷 66-80页

作者： Edoardo BUCCHIGNANI Paola MErCOGLIANO hans-ju¨rgen PANITZ Myriam MONTESArCHIO Euro Mediterranean Center on Climate Change(CMCC) Capua CE 81043Italy Italian Aerospace research Center(CIrA) Capua CE 81043Italy Institute of Meteorology and Climate research-Department Troposphere research(IMK-TrO) Karlsruhe Institute of Technology(KIT)Karlsruhe 76131Germany

In this study,projected changes in the future climate conditions for the Middle EasteNorth Africa domain over the 21st century have been *** simulations with the COSMO-CLM model have been conducted respectively,at a spatial resolution of 0.44 and 0.22,over the period 1979e2100,employing the IPCC rCP4.5 *** and boundary conditions have been derived by the global model *** main aim of the work is to provide regional climate projections for this area,widening the range of the data already available,yet with higher resolution,useful for many applications,especially as an input for the impact *** two different resolutions have been employed in order to quantify the differences due to the spatial scale effects,comparing the results also with the driving global *** projections show a significant warming expected over the whole area considered at the end of the 21st century,along with a reduction in precipitation,which is particularly evident over the western part of the *** projections depend on the horizontal resolution,suggesting the need for additional simulations at higher resolution,especially for a proper representation of extreme weather events.

关键词： COSMO-CLM Middle EasteNorth IPCC rCP4.5

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