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Direct Measurement of CO_2 Retention in Arable Soils with pH Above 6.5 During Barometric Process Separation Incubation

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Pedosphere 2018年第5期28卷 726-738页

作者： Hannah CONRADS joachim INGWERSEN JU Xiaotang Thilo STRECK Institute of Soil Science and Land Evaluation Biogeophysics SectionUniversity of Hohenheim College of Agricultural Resources and Environmental Sciences China Agricultural University

The barometric process separation(BaPS)technique is a well-established incubation method to simultaneously measure gross nitrification and respiration rates in *** application,however,is still critical in soils with pH above ***,a substantial part of microbial CO_2 production is retained in soil solution(CO_2,aq)due to shifts in the carbonate *** may lead to substantial errors in gas balance ***,utilization of the BaPS technique is only reliable if the critical term is adequately *** present an easy,inexpensive,and direct method,the sterilization-CO_2-injection(SCI)method,to measure CO_2 retention during soil *** soil was incubated in the BaPS system,and defined volumes of CO_2 were injected to stepwise increase CO_2partial pressure(p CO_2)inside the chamber and to analyse the physicochemical equilibration *** exemplary agricultural soils from Northeast China and Southwest Germany were used for method establishment,presenting pH values between 4.4 and 7.6 and carbonate contents between 0% and 3.9%.We observed that in soils with pH>6.5,70%–90% of the injected CO_2 was taken up by the soil until the equilibrium inside the chamber was *** expected,in soils with low pH(<6.5),measured CO_2 retention was ***_2 retention patterns were sensitive to incubation temperature with tri-fold dissolution capacity at 5~?C compared to 25?C,but insensitive to variations in soil water *** resulting soil-specific relationship between p CO_2 and CO_2,aq concentration allowed the quantification of CO_2,aq concentration as a function of headspace p CO_2.

关键词：孵化期间土壤分离气压 pH 测量 BaPS 孵化方法

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Review of History and Recent Development of Organic Farming Worldwide

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Agricultural Sciences in China 2006年第3期5卷 169-178页

作者： MA Shi-ming joachim Sauerborn Institute for Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Centre for Agriculture in the Tropics ＆ Subtropics University of Hohenheim Stuttgart 70593 Germany

The history of the organic farming worldwide was reviewed in this paper. The development of the organic farming worldwide had gone through three stages, emergence, expansion, and growth. The contributors and their thoughts during the different development stages of the organic farming were briefly introduced. And the development status of the organic farming worldwide was reviewed from the aspects of land area under organic management, land area under organic management in percentage of total agricultural area, and world markets for organic products. Besides, the main existing problems for the further development of the world＇s organic farming, as well as the development status, problems and strategies of the Chinese organic farming were discussed.

关键词： organic farming organic product review of history development status

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Biosynthesis of Monoterpenoid Indole AlkaloidAjmaline Catalyzed by Novel Reductases

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Chemical Research in Chinese Universities 2006年第2期22卷 267-269页

作者： Gerald von Schumann joachim Stckigt Department of Pharmaceutical Biology Institute of Pharmacy Johannes Gutenberg University Staudinger Weg 5 D-55099 Mainz Germany

Introduction One of the major root alkaloids of the Indian medicinal plant Rauvolfia serpenlina Benth. ex Kurz is named ajmaline. The enzymatic biosynthesis of this alkaloid has been studied for a long time by our group As a result, a biosynthetic pathway has been established, in which about 10 enzymes participate, several of them belonging to the group of NADPH-dependent reductases. Started with the biosynthetic precursors tryptamine and secologanin,

关键词： Biosynthesis Alkaloid Reductase Ajmaline

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On Unitary N-Dilations for Tuples of Circulant Contractions and von Neumann’s Inequality

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American Journal of Computational Mathematics 2023年第4期13卷 594-606页

作者： joachim Moussounda Mouanda Edwige Josette Maleka Koubemba Djagwa Dehainsala Mathematics Department Blessington Christian University Nkayi Republic of the Congo Mathematics Department N’Djamena University N’Djamena Tchad

We introduce the spectral mapping factorization of tuples of circulant matrices and its matrix version. We prove that every tuple of circulant contractions has a unitary N-dilation. We show that von Neumann’s inequality holds for tuples of circulant contractions. We construct completely contractive homomorphisms over the algebra of complex polynomials defined on .

关键词： Dilations Polynomials Matrices

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Latent HIV-1 TAR Regulates 7SK-responsive P-TEFb Target Genes and Targets Cellular Immune Responses in the Absence of Tat

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Genomics, Proteomics & Bioinformatics 2017年第5期15卷 313-323页

作者： Sebastian Eilebrecht Bernd-joachim Benecke Arndt G. Benecke CNRS UMR8246 Université Pierre et Marie Curie Paris 75005 France ACSIOMA GmbH Technologiezentrum Ruhr Bochum 44799 Germany Center for Innate Immunity and Immune Disease University of Washington School of Medicine Seattle WA 98195 USA

The transactivating response element （TAR） structure of the nascent HIV-1 transcript is critically involved in the recruitment of inactive positive transcription elongation factor b （P-TEFb） to the promoter proximal paused RNA polymerase II. The viral transactivator Tat is responsible for subsequent P-TEFb activation in order to start efficient viral transcription elongation. In the absence of the viral transactivator of transcription （Tat）, e.g., during latency or in early stages of HIV tran- scription, TAR mediates an interaction of P-TEFb with its inhibitor hexamethylene bis-aeetamide- inducible protein 1 （HEXIM1）, keeping P-TEFb in its inactive form. In this study, we address the function of HIV-1 TAR in the absence of Tat by analyzing consequences of HIV-1 TAR overexpres- sion on host cellular gene expression. An RNA chimera consisting of Epstein-Barr virus-expressed RNA 2 （EBER2） and HIV-1 TAR was developed to assure robust overexpression of TAR in HEK293 cells. The overexpression results in differential expression of more than 800 human genes. A significant proportion of these genes is involved in the suppression of cellular immune responses, including a significant set of 7SK-responsive P-TEFb target genes. Our findings identify a novel role for HIV-1 TAR in the absence of Tat, involving the interference with host cellular immune responses by targeting 7SK RNA-mediated gene expression and P-TEFb inactivation.

关键词： HIV-1 Latency TAR 7SK RNA Cellular immunity

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Assessing Possibilities and Limitations for Biomarker Analyses on Outcrop Samples:A Case Study on Carbonates of the Shibantan Member (Ediacaran Period, Dengying Formation, South China)

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Acta Geologica Sinica(English Edition) 2014年第6期88卷 1696-1704页

作者： Jan-Peter DUDA Volker THIEL joachim REITNER Martin BLUMENBERG Geoscience Centre Geobiology Group Georg-August-University GttingenGoldschmidtstr.337077 Gttingen Germany Federal Institute for Geosciences and Natural Resources (BGR) Stilleweg 2 30655 Hannover Germany

The Shibantan Member（Dengying Formation, South China） represents one of only two carbonate settings with Ediacara-type organisms and offers a rare opportunity to study the biogeochemistry of these ecosystems. To evaluate possibilities and limitations for future biomarker studies on fossil-bearing outcrop samples of the Shibantan Member, we analysed the spatial distribution of hydrocarbons in extractable organic matter（i.e. bitumen） on a millimetre scale. Our study demonstrates that the sample and most likely also other rocks from the same setting are contaminated with petroleum-derived compounds that bear the potential for erroneous interpretations in palaeo-reconstructions. The contamination was revealed by distribution patterns and amounts of extractable n-alkanes and acyclic isoprenoids. The contamination is linked to the external weathering surfaces but also to cracks within the rock, and the extent most likely depends on concentration gradients between these contamination sources. Here we show that contamination can successfully be distinguished from syngenetic signals obtained from non-extractable organic matter（i.e. kerogen） using catalytic hydropyrolysis（Hy Py）. However, we observed that decalcification is necessary to achieve sufficient yields of kerogen-bound hydrocarbons and to avoid artificial alteration of the biomarker signals due to matrix effects.

关键词： Ediacaran biomarkers contamination syngeneity slice-experiments catalytic hydropyrolysis(HyPy)

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Selected Recent Applications of Sparse Grids

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 47-77页

作者： Benjamin Peherstorfer Christoph Kowitz Dirk Pfluger Hans-joachim Bungartz Scientific Computing Group Dept.of Computer ScienceBoltzmannstr.385748 GarchingGermany Institutefor Advanced Study Technische UniversitätMünchenLichtenbergstr.2a85748 GarchingGermany Institute for Parallel and Distributed Systems University of StuttgartUni-versitätsstr.3870569 StuttgartGermany

Sparse grids have become a versatile tool for a vast range of applications reaching from interpolation and numerical quadrature to data-driven problems and uncertainty *** review four selected real-world applications of sparse grids:financial product pricing with the Black-Scholes model,interactive explo-ration of simulation data with sparse-grid-based surrogate models,analysis of simu-lation data through sparse grid data mining methods,and stability investigations of plasma turbulence simulations.

关键词： Sparse grids hierarchical decomposition adaptivity combination technique

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Treatment of biliary tract cancer with NVP-AEW541:Mechanisms of action and resistance

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World Journal of Gastroenterology 2010年第2期16卷 156-166页

作者： Samuel Wolf Jana Lorenz joachim Mssner Marcus Wiedmann Department of Internal MedicineⅡ University of Leipzig Department of Internal MedicineⅠ St. Mary's Hospital

AIM:To investigate in vitro treatment with NVPAEW541,a small molecule inhibitor of insulin-like growth factor-1 receptor(IGF-1R),in biliary tract cancer (BTC),since this disease is associated with a poor prognosis due to wide resistance to chemotherapeutic agents and ***:Cell growth inhibition by NVP-AEW541 was studied in vitro in 7 human BTC cell lines by automated cell *** addition,the anti-tumoral mechanism of NVP-AEW541 was studied by Western blotting,cell cycle analysis and reverse transcription-polymerase chain reaction(RT-PCR).Anti-tumoral drug effect in combination with gemcitabine,5-fluorouracil(5-FU)and Polo-like kinase 1 inhibitor BI2536 was also studied. RESULTS:In vitro treatment with NVP-AEW541 suppressed growth in all human BTC cell lines,however response was lower in gallbladder *** withNVP-AEW541 was associated with dephosphorylation of IGF-1R and *** contrast,phosphorylation of p42/p44 and Stat3 and expression of Bcl-xL were inconsistently *** addition,treated cells showed cell cycle arrest at the G1/S-checkpoint and an increase in sub-G1 ***,IGF-1R and its ligands IGF-1 and IGF-2 were co-expressed in RT-PCR,suggesting an autocrine loop of tumor cell *** with gemcitabine,NVP-AEW541 exerted synergistic effects, particularly at low concentrations,while effects of combination with 5-FU or BI 2536 were only additive. CONCLUSION:Our findings suggest that NVP-AEW541 is active against BTC in vitro and potentiates the efficacy of gemcitabine.

关键词： Tyrosine kinase inhibitor Cholangiocarcinoma Gemcitabine NVP-AEW541

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Modified Helicobacter test using a new test meal and a 13C-urea breath test in Helicobacter pylori positive and negative dyspepsia patients on proton pump inhibitors

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World Journal of Gastroenterology 2017年第32期23卷 5954-5961页

作者： Bojan Tepes Peter Malfertheiner joachim Labenz Sitke Aygen AM DC Rogaska Prvomajska 29 A3250 Rogaska SlatinaSlovenia Universitatsklinikum Magdeburg A.o.R Klinik für Gastroenterologie Hepatologie und Infektiologie39120 MagdeburgGermany Department of Internal Medicine and Gastroenterology Diakonie KlinikumJung-Stilling Hospital Institut für Biomedizinische Analytik und NMR-Imaging GmbH(INFAI)

AIM To determine the sensitivity and specificity of the ^(13)C-urea breath test(UBT) in patients taking proton pump inhibitors(PPIs), using a new test meal Refex. METHODS One hundred and fourteen consecutive patients with dyspepsia, 53 Helicobacter pylori(H. pylori) positive, 49 H. pylori negative, were included in the study. The patients were then given esomeprazole 40 mg for 29 consecutive days, and the ^(13)C-UBT with the new test meal was performed the next morning. RESULTS The sensitivity of the ^(13)C-UBT with a cut off 2.5‰ was92.45%(95%CI: 81.79%-97.91%) by per-protocol(PP) analysis and 78.13 %(95%CI: 66.03%-87.49%) by intention-to-treat(ITT) analysis. The specificity of the ^(13)C-UBT test was 96.00 % in the ITT population(95%CI: 86.29%-99.51%) and 97.96% in the PP population(95%CI: 89.15%-99.95%).CONCLUSION The new test meal based ^(13)C-UBT is highly accurate in patients on PPIs and can be used in those unable to stop their PPI treatment.

关键词： Urea breath test new test meal Proton pump inhibitors Prospective randomized clinical trial Helicobacter pylori

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Computer animations of color markings revealthe function of visual threat signals inNeolamprologus pulcher

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Current Zoology 2017年第1期63卷 45-54页

作者： Valentina BALZARINI Michael TABORSKY Fabienne VILLA joachim G. FROMMEN Institute of Ecology and Evolution Behavioral Ecology Division University of Bern Wohlenstrasse 50a 3032Hinterkappelen Switzerland

Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent＇s state or motivation. Communication of aggressive propensity is particularly importantin group-living animals with a stable dominance hierarchy, as the outcome of aggressive inter-actions determines the social rank of group members. Neolamprologus pulcher is a cooperativelybreeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical blackstripes on the operculum that vary naturally in shape and darkness. During frontal threat displaysthese patterns are actively exposed to the opponent, suggesting a signaling function. To investi-gate the role of operculum stripes during contests we manipulated their darkness in computeranimated pictures of the fish. We recorded the responses in behavior and stripe darkness of testsubjects to which these animated pictures were presented. Individuals with initially darker stripeswere more aggressive against the animations and showed more operculum threat *** stripes of test subjects became darker after exposure to an animation exhibiting a paleoperculum than after exposure to a dark operculum animation, highlighting the role of the dark-ness of this color pattern in opponent assessment. We conclude that （i） the black stripes on theoperculum of N. pulcherare a reliable signal of aggression and dominance, （ii） these markings playan important role in opponent assessment, and （iii） 2D computer animations are well suited to elicitbiologically meaningful short-term aggressive responses in this widely used model system ofsocial evolution.

关键词： aggression, agonistic behavior, animated pictures, cichlid fish, communication, cooperation, social, threat display.

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