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Human-driven topographic effects on the distribution of forest in a flat, lowland agricultural region

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Journal of Geographical Sciences 2014年第1期24卷 76-92页

作者： Mette v. ODGAARD Peder K. BOCHER Tommy DALGAARD Jesper E. MOESLUND jens-Christian SvENNING Department of Agroecology Aarhus University Blichers AIIe 20 DK-8830 Tjele Denmark Ecoinformatics & Biodiversity Group Department of Bioscience Aarhus University Ny Munkegade 114DK-8000 Aarhus C Denmark Department of Computer Science Aarhus University Abogade 34 DK-8200 Aarhus N Denmark

Complex topography buffers forests against deforestation in mountainous regions. However, it is unknown if terrain also shapes forest distribution in lowlands where human impacts are likely to be less constrained by terrain. In such regions, if important at all, to- pographic effects will depend on cultural-historical factors and thus be human-driven （an- thropogenic） rather than natural, except in regions where the general climate or extreme soils limit the occurrence of forests. We used spatial regression modeling to assess the extent to which topographic factors explain forest distribution （presence-absence at a 48x48 m resolu- tion） in a lowland agricultural region （Denmark, 43,075 km2） at regional and landscape scales （whole study area and 10x10 km grid cells, respectively）, how landscape-scale for- est-topography relationships vary geographically, and which potential drivers （topographic heterogeneity, forest cover, clay content, coastal/inland location） determine this geographic heterogeneity. Given a moist temperate climate and non-extreme soils all landscapes in Denmark would naturally be largely forest covered, and any topographic relationships will be totally or primarily human-driven. At regional scale, topographic predictors explained only 5% of the distribution of forest. In contrast, the explanatory power of topography varied from 0%-61% at landscape scale, with clear geographic patterning. Explanatory power of topog- raphy at landscape scale was moderately dependent on the potential drivers, with topog- raphic control being strongest in areas with high topographic heterogeneity and little forest cover. However, these conditioning effects were themselves geographically variable. Our findings show that topography by shaping human land-use can affect forest distribution even in flat, lowland regions, but especially via localized, geographically variable effects.

关键词： Europe forest cover geographically weighted regression human impact landscape development topography vegetation distribution.

Liver cirrhosis and arterial hypertension

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World Journal of Gastroenterology 2006年第5期12卷 678-685页

作者： jens H Henriksen Soren Moller Department of Clinical Physiology 239University of CopenhagenH:S Hvidovre HospitalCopenhagenDenmark

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems （renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin）, and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin generelated peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective （although relative） counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension （essential, secondary） may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.

关键词： Arterial compliance Central vascular filling Chyperdynamic circulation Kidney function, Nitric oxide Blood pressure regulation Renin-angiotensin-aldosterone system Sympathetic nervous system vasodilatation vasoconstriction

Copper-Catalyzed Carbonylative Synthesis of β-Boryl Amides via Boroamidation of Alkenes

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CCS Chemistry 2021年第4期3卷 2643-2654页

作者： Fu-Peng Wu jens Holz Yang Yuan Xiao-Feng Wu Leibniz-Institut für Katalyse e.v.an der Universität Rostock Rostock 18059 Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023

β-Boryl amide is a class of high value intermediates in organic *** this work,a copper-catalyzed carbonylative boroamidation of olefins toward the synthesize ofβ-boryl amides has been *** new chemical bonds were constructed in this transformation.A wide range ofβ-boryl amides were produced in excellent regioselectivity and good to excellent *** gas can be successfully transformed under the same standard conditions as ***,with the use of a chiral ligand,the first example of enantioselective carbonylative boroamidation of alkenes was *** addition,Piposulfan and Pipobroman,antineoplastic medicines,were prepared by this methodology in a straightforward manner.

关键词： carbonylative boroamidation copper catalyst enantioselective olefins

Treatment of hepatitis C virus infection

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World Journal of Gastroenterology 2007年第13期13卷 1897-1905页

作者： Kilian Weigand Wolfgang Stremmel jens Encke University of Heidelberg Department of Gastroenterology and Hepatology Im Neuenheimer Feld 410 Heidelberg 69120 Germany

Acute and chronic hepatitis C virus (HCv) infection remains a serious health problem worldwide, however, there has been advancement in the treatment of HCv infection due to standard treatment using pegylated interferon and ribavirin. The literature indicates that therapy for HCv is becoming more individualized. In addition to considering genotype and viral RNA levels before treatment, achievement of an early virologic response (EvR) and a rapid virologic response (RvR) is now possible during therapy. Moreover, problem patients, such as non-responders, relapsers, HIv or HBv co- infected patients, patients with liver cirrhosis, and pre- or post-liver transplantation patients are an increasing fraction of the patients requiring treatment. This article reviews the literature regarding standard treatments and problem patients with acute and chronic HCv infection. It also includes discussion on contraindications and side effects of treatment with interferon and ribavirin, as well as new drug development.

关键词： Hepatitis C virus Acute and chronic HCvinfection Treatment Pegylated interferon Ribavirin Sustained virologic response Non-responders Relapsers

Obeticholic acid for severe bile acid diarrhea with intestinal failure:A case report and review of the literature

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World Journal of Gastroenterology 2018年第21期24卷 2320-2326页

作者： Christian Lodberg Hvas Peter Ott Peter Paine Simon Lal Soren Peter Jorgensen jens Frederik Dahlerup Department of Hepatology and Gastroenterology Aarhus University HospitalAarhus C 8000Denmark Department of Gastroenterology Salford Royal NHS Foundation TrustSalfordManchester M6 8HDUnited Kingdom

Bile acid diarrhea results from excessive amounts of bile acids entering the colon due to hepatic overexcretion of bile acids or bile acid malabsorption in the terminal ileum. The main therapies include bile acid sequestrants, such as colestyramine and colesevelam, which may be given in combination with the opioid receptor agonist loperamide. Some patients are refractory to conventional treatments. We report the use of the farnesoid X receptor agonist obeticholic acid in a patient with refractory bile acid diarrhea and subsequent intestinal failure. A 32-year-old woman with quiescent colonic Crohn's disease and a normal terminal ileum had been diagnosed with severe bile acid malabsorption and complained of watery diarrhea and fatigue. The diarrhea resulted in hypokalemia and sodium depletion that made her dependent on twice weekly intravenous fluid and electrolyte infusions. Conventional therapies with colestyramine, colesevelam, and loperamide had no effect. Second-line antisecretory therapies with pantoprazole, liraglutide, and octreotide also failed. Third-line treatment with obeticholic acid reduced the number of stools from an average of 13 to an average of 7 per 24h and improved the patient's quality of life. The fluid and electrolyte balances normalized. The effect was sustained during follow-up for 6 mo with treatment at a daily dosage of 25 mg. The diarrhea worsened shortly after cessation of obeticholic acid. This case report supports the initial report that obeticholic acid may reduce bile acid production and improve symptoms in patients with bile acid diarrhea.

关键词： Bile acid malabsorption Diarrhea Farnesoid X-activated receptor Crohn’s disease

A Compact Dual-Band Quasi-Elliptic Filter Employing Meander-Line-and CRLH-Based SIW Triplets

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Electromagnetic Science 2024年第3期2卷 79-85页

作者： Yilong Zhu Yuandan Dong Lin Gu Deisy Formiga Mamedes jens Bornemann School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Department of Electrical and Computer Engineering University of VictoriaVictoriaBC V8W 2Y2Canada

A compact dual-band quasi-elliptic filter with high selectivity is developed and investigated in this *** employs two hybrid-structure substrate integrated waveguide(SIW)triplets,which show completely inverse transfer responses under the same conditions of inductive cross *** first meander-line-based triplet is able to produce a transmission zero(TZ)above the *** the second SIW triplet,which is composed by a composite right/left-handed(CRLH)resonator,creates a TZ below the *** utilizing these features,a dual-band quasi-elliptic filter based on SIW dual-mode resonances(TE101 and TE201),whose operating frequencies are allocated at 8 GHz and 10 GHz,is designed for *** design process,principles,and experiments are carefully described in this *** measured and simulated results are in good agreement,indicating excellent electrical performance with low loss,compact device size and high *** most notable point is that a dual-band quasi-elliptic filter on SIW platforms is obtained with all inductive couplings for the first time,which shows a unique benefit in eliminating negative-coupling structures while permitting miniaturization for SIW dual-band filter design.

关键词： Dual-band quasi-elliptic filter High selectivity Compact size Meander-line and CRLH resonators Substrate integrated waveguide

Parallel arrays of Schottky barrier nanowire field effect transistors： Nanoscopic effects for macroscopic current output

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Nano Research 2013年第6期6卷 381-388页

作者： Sebastian Pregl Walter M. Weber Daijiro Nozaki jens Kunstmann Larysa Baraban Joerg Opitz Thomas Mikolajick Gianaurelio Cuniberti Institute for Materials Science and Max Bergmann Center of Biomaterials TU Dresden Dresden 01062 Germany NaMLab GmbH Dresden 01187 Germany Fraunhofer Institute IZFP Dresden Dresden 01109 Germany Institute for Semiconductors and Microsystems Technology TU Dresden Dresden 01187 Germany Division of IT Convergence Engineering POSTECH Pohang Korea

We present novel Schottky barrier field effect transistors consisting of a parallel array of bottom-up grown silicon nanowires that are able to deliver high current outputs. Axial silicidation of the nanowires is used to create defined Schottky junctions leading to on/off current ratios of up to 106. The device concept leverages the unique transport properties of nanoscale junctions to boost device performance for macroscopic applications. Using parallel arrays, on-currents of over 500 gA at a source-drain voltage of 0.5 v can be achieved. The transconductance is thus increased significantly while maintaining the transfer characteristics of single nanowire devices. By incorporating several hundred nanowires into the parallel arra36 the yield of functioning transistors is dramatically increased and device- to-device variability is reduced compared to single devices. This new nanowire- based platform provides sufficient current output to be employed as a transducer for biosensors or a driving stage for organic light-emitting diodes （LEDs）, while the bottom-up nature of the fabrication procedure means it can provide building blocks for novel printable electronic devices.

关键词： silicon nanowire effective Schottky barrier lowering parallel arra^electric field enhancement output current amplification

A cis-Regulatory Sequence Acts as a Repressor in the Arabidopsis thaliana Sporophyte but as an Activator in Pollen

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Molecular Plant 2017年第5期10卷 775-778页

作者： Robert D. Hoffmann Lene I. Olsen Jeppe O. Husum Jesper S. Nicolet jens F.B. Thøfner Anders P. Wätjen Chukwuebuka v. Ezike Michael Palmgren Department of Plant and Environmental Sciences Center for Membrane Pumps in Cells and Disease - PUMPKIN Danish National Research Foundation University of Copenhagen 1871 Frederiksberg C Denmark

Dear Editor, Flowering plants undergo a life cycle in which the diploid sporo- phyte constitutes the predominant generation, and the haploid male and female gametophytes are reduced to only a few but highly specialized cells （McCormick, 1993）. To achieve expression restricted to certain cell types, genes are not only actively expressed in these cells, they might also be repressed elsewhere. Here, we report that deleting an 88-base-pair （bp） promoter sequence of the pollen-specific gene ACA7 redirects its expression to the sporophyte.

关键词： Flowering plants life cycle diploid sporophyte constitutes

Perforated midgut diverticulitis:Revisited

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World Journal of Gastroenterology 2012年第34期18卷 4714-4720页

作者： Milan Spasojevic jens Marius Naesgaard Dejan Ignjatovic Department of Gastrointestinal Surgery Vestfold Hospital3103 TonsbergNorway Department of Digestive Surgery Akershus University HospitalUniversity of Oslo1478 LorenskogNorway

AIM:To study and provide data on the evolution of medical procedures and outcomes of patients suffering from perforated midgut diverticulitis. METHODS:Three data sources were used:the Medline and Google search engines were searched for case reports on one or more patients treated for perforated midgut diverticulitis (Meckel's diverticulitis excluded) that were published after 1995. The inclusion criterion was sufficient individual patient data in the article. Both indexed and non-indexed journals were used. Patients treated for perforated midgut diverticulitis at vestfold Hospital were included in this group. Data on symptoms, laboratory and radiology results, treatment modalities, surgical access, procedures, complications and outcomes were collected. The Norwegian patient registry was searched to find patients operated upon for midgut diverticulitis from 1999 to 2007. The data collected were age, sex, mode of access, surgical procedure performed and number of patients per year. Historical controls were retrieved from an article published in 1995 containing pertinent individual patient data. Statistical analysis was done with SPSS ***:GroupⅠ:106 patients (48 men) were found. Mean age was 72.2 ± 13.1 years (mean ± SD). Age or sex had no impact on outcomes (P = 0.057 and P = 0.771, respectively). Preoperative assessment was plain radiography in 53.3% or computed tomography (CT) in 76.1%. Correct diagnosis was made in 77.1% with CT, 5.6% without (P = 0.001). Duration of symptoms before hospitalization was 3.6 d (range:1-35 d), but longer duration was not associated with poor outcome (P = 0.748). Eighty-six point eight percent of patients underwent surgery, 92.4% of these through open access where 90.1% had bowel resection. Complications occurred in 19.2% of patients and 16.3% underwent reoperation. Distance from perforation to Treitz ligament was 41.7 ± 28.1 cm. At surgery, no peritonitis was found in 29.7% of patients, local peritonitis in 47.5%, and dif

关键词： Intestinal Small bowel Jejunum Ileum Perforation Diverticulitis Conservative treatment