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Annual-perennial plant relationships and species selection for desert restoration

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Journal of Arid Land 2013年第3期5卷 298-309页

作者： s.ott r abella stanley D sMITH Department of Environmental and Occupational Health University of Nevada Las VegasLas VegasNevada 89154-3064USA school of Life sciences University of Nevada Las VegasLas VegasNevada 89154-4004USA

Exotic plant invasion is a growing concern in the conservation and management of indigenous arid land ecosystems. By creating areas of ameliorated microclimates and fertile soil below their canopies, perennial plants might influence exotic annual plant invasions. We conducted a quantitative literature review of studies that compared exotic annual plant abundance among native perennial plant species and interspace （open areas） microsites in North America＇s Mojave Desert, where exotic plant invasion has corresponded with increasing extent of wildfire and broad-scale ecosystem transformation. Ten studies compared exotic annual plant abundance between inter- spaces and below a total of 36 native perennial species. These studies revealed that：（1） With few exceptions, most native perennial species supported a greater abundance of exotic annuals than interspaces, indicating overall facilitation of exotic species by native perennials. （2） Exotic species abundance varied by orders of magnitude among native perennial species, with some perennial species harboring amounts of exotics similar to interspaces. （3） Distributions of dominant exotic species varied, where Bromus rubens displayed a greater affinity for below-perennial microsites than did schismus spp. and Erodium cicutarium that often were most abundant in interspaces. results suggest that the degree of facilitation of exotic plants warrants consideration when selecting native perennial species for revegetation and restoration projects.

关键词： Bromus rubens exotic fertile island invasive nurse plant positive plant interaction schismus

Observing the stages of bystander intervention in virtual reality simulation

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World Journal of Emergency Medicine 2019年第3期10卷 145-151页

作者： David G. Buckler Alfredo Almodovar Jr Paul snobelen Benjamin s. abella Audrey Blewer Marion Leary Center for resuscitation science University of Pennsylvania Philadelphia PA 19104 USA Peel regional Paramedic service 1600 Bovaird Dr. E Brampton ON L6R 3S8 Canada Department of Community & Family Medicine Duke University Medical Center DUMC 2914 Durham NC 27710 USA school of Nursing University of Pennsylvania 418 Guardian Drive Philadelphia PA 19104 USA

BACKGrOUND: Understanding bystander reactions to an emergency is an important component of effective training. Four stages of bystander intervention (BI) have been previously described: noticing the situation as a problem, interpreting when it is appropriate to intervene, recognizing personal responsibility to intervene, and knowing how to intervene. Using virtual reality (Vr) to simulate emergencies such as sudden cardiac arrest (sCA) can be used to study these stages. METHODs: In a secondary analysis of an observational cohort study, we analyzed bystander self-effi cacy for stages of BI before and after simulated sCA. Each subject participated in a singleplayer, immersive, Vr sCA scenario. subjects interacted with simulated bystanders through voice commands (“call 911”,“get an AED”). Actions taken in scenario, like performing CPr, were documented. scenario BI actions were compared based on dichotomized comfort/discomfort. rEsULTs: From June 2016 to June 2017, 119 subjects participated. Average age was 37±14 years, 44% were female and 46% reported CPr training within 2 years. During the scenario, 98%“noticed the event” and “interpreted it as a problem”, 78%“took responsibility”, and 54%“possessed the necessary skills”. self-effi cacy increased from pre- to post-scenario: noticing the event increased from 80% to 96%;interpreting as a problem increased from 86% to 97%;taking responsibility increased from 56% to 93%;possessing necessary skills increased from 47% to 63%(PsION: self-efficacy to respond to an sCA event increased pre- to post-scenario. Bystanders who reported feeling comfortable “taking responsibility to intervene” during an emergency were more likely to take action during a simulated emergency.

关键词： Virtual reality Bystander intervention Emergency preparedness

Vitamin D deficiency in cirrhosis relates to liver dysfunction rather than aetiology

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World Journal of Gastroenterology 2011年第7期17卷 922-925页

作者： Mikkel Malham sΦren Peter JΦrgensen Peter ott JΦrgen Agnholt Hendrik Vilstrup Mette Borre Jens F Dahlerup Department of Medicine V (Hepatology and Gastroenterology) Aarhus University Hospital

AIM: To examine the vitamin D status in patients with alcoholic cirrhosis compared to those with primary biliary cirrhosis. METHODs: Our retrospective case series comprised 89 patients with alcoholic cirrhosis and 34 patients with primary biliary cirrhosis who visited our outpatient clinic in 2005 and underwent a serum vitamin D status assessment. rEsULTs: Among the patients with alcoholic cirrhosis, 85% had serum vitamin D levels below 50 nmol/L and 55% had levels below 25 nmol/L, as compared to 60% and 16% of the patients with primary biliary cirrhosis, respectively (P roups, serum vitamin D levels decreased with increasing liver disease severity, as determined by the Child-Pugh score. CONCLUsION: Vitamin D deficiency in cirrhosis relates to liver dysfunction rather than aetiology, with lower levels of vitamin D in alcoholic cirrhosis than in primary biliary cirrhosis.

关键词： Alcoholic liver cirrhosis Child-Pugh score Primary biliary cirrhosis Vitamin D deficiency

A micromechanical model for efective conductivity in granular electrode structures

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Acta Mechanica sinica 2013年第5期29卷 682-698页

作者： Julia ott Benjamin Vlker Yixiang Gan robert M.Mc Meeking Marc Kamlah Institute of Applied Materials Karlsruhe Institute of Technology76131 Karlsruhe Germany Department of Mechanical Engineering University of CaliforniaSanta BarbaraCA 93106 USA school of Civil Engineering The University of SydneyNSW 2006 Australia Materials Department University of CaliforniaSanta BarbaraCA 93106 USA school of Engineering University of AberdeenKing’s CollegeAberdeenAB24 3UE Scotland UK INM-Leibniz Institute for New Materials Campus D22 66123 Saarbrücken Germany

Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （sOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both sOFC and LIB are modeled as a binary mixture of electronic and ionic conducting particles to estimate effective transport properties. Particle packings of 10000 spherical, binary sized and randomly positioned particles are created numerically and densified considering the different manufacturing processes in sOFC and LIB： the sintering of sOFC electrodes is approximated geometrically, whereas the calendering process and volume change due to intercalation in LIB are modeled physically by a discrete el- ement approach. A combination of a tracking algorithm and a resistor network approach is developed to predict the con- nectivity and effective conductivity for the various densified structures. For sOFC, a systematic study of the influence of morphology on connectivity and conductivity is performed on a large number of assemblies with different compositions and particle size ratios between 1 and 10. In comparison to percolation theory, an enlarged percolation area is found, es- pecially for large size ratios. It is shown that in contrast to former studies the percolation threshold correlates to varying coordination numbers. The effective conductivity shows not only an increase with volume fraction as expected but also with size ratio. For LIB, a general increase of conductivity during the intercalation process was observed in correlation with increasing contact forces. The positive influence of cal- endering on the percolation threshold and the effective conductivity of carbon black is shown. The anisotropy caused by the calendering process does not influence the carbon black phase.

关键词： Granular electrode structures Effective conductivity - Percolation

smoking increases the risk of extraintestinal manifestations in Crohn's disease

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World Journal of Gastroenterology 2014年第34期20卷 12269-12276页

作者： Claudia ott Angela Takses Florian Obermeier Elisabeth schnoy Martina Müller Department of Internal Medicine I University of Regensburg93042 RegensburgGermany

AIM:To demonstrate a high prevalence of extraintestinal manifestations(EIMs)in a prospective populationbased cohort of inflammatory bowel disease(IBD)patients at first diagnosis as well as during the early course of the ***:EIMs are common in patients with *** on the frequency of EIMs have mostly been assessed in patients from tertiary centers;however,data about the prevalence of EIMs at first diagnosis as well as factors influencing their incidence during the early course of disease from prospective population-based cohorts are *** present data of patients of our population-based"Oberpfalz cohort"(Bavaria,Germany)from first diagnosis(up to 3 mo after first diagnosis)as well as during the early course of the *** risk factors were assessed by calculating the relative risk(rr)as well as using logistic regression ***:In total,data of 257 newly diagnosed patients with IBD were evaluated[161 Crohn’s disease(CD),96 ulcerative colitis(UC)].Median duration of follow-up was 50 mo after first *** 63.4%of all patients(n=163),an EIM was diagnosed at any point during the observation *** first diagnosis,patients with CD had a significantly increased risk of an EIM[n=69(42.9%)]compared with UC patients[n=21(21.9%);Prr=1.96;95%CI:1.30-2.98].Active smoking increased the risk of CD patients developing an EIM during the early course of the disease,but notably not of UC patients(P=0.046;rr=1.96;95%CI:1.01-3.79).In addition,using logistic regression analysis,the need for IBD-related surgery and a young age at first diagnosis were identified as risk factors for the development of an EIM in CD *** association with EIMs was found for the factors sex,localization of the disease and positive family history of *** contrast,no key factors which increased the risk of development of an EIM could be identified in UC ***:We found a high prevalence of EIM in this cohort at first diagnosis and during th

关键词： Extraintestinal manifestations Crohn's disease Ulcerative colitis smoking surgery Age at onset

The association of layperson characteristics with the quality of simulated cardiopulmonary resuscitation performance

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World Journal of Emergency Medicine 2017年第1期8卷 12-18页

作者： Marion Leary David G.BucMer Daniel J.Ikeda Daiane A.saraiva robert A.Berg Vinay M.Nadkarni Audrey L.Blewer Benjamin s.abella Center for resuscitation science and Department of Emergency Medicine Department of Emergency MedicinePerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA school of Nursing University of PennsylvaniaPhiladelphiaPennsylvaniaUSA Children's Hospital of Philadelphia PhiladelphiaPennsylvaniaUSA

BACKGrOUND: Few studies have examined the association of layperson characteristics with cardiopulmonary resuscitation(CPr) provision. Previous studies suggested provider characteristics, including age and gender, were associated with CPr quality, particularly chest compression(CC) depth. We sought to determine the association of subject characteristics, including age and gender with layperson CPr quality during an unannounced simulated CPr event. We hypothesized shallower CC depth in females, and older-aged ***: As part of a larger multicenter randomized controlled trial of CPr training for cardiac patients' caregivers, CPr skills were assessed 6 months after training. We analyzed associations between subject characteristics and CC rate, CC depth and no-? ow time. Each variable was analyzed independently; signi? cant predictors determined via univariate analysis were assessed in a multivariate regression ***: A total of 521 laypersons completed a 6-month CPr skills assessment and were included in the analysis. Mean age was 51.8±13.7 years, 75% were female, 57% were Caucasian. Overall, mean CC rate was 88.5±25.0 per minute, CC depth was 50.9±2.0 mm, and mean no-flow time was 15.9±2.7 sec/min. CC depth decreased signi? cantly in subjects >62 years(Psubjects performed deeper CCs than female subjects(47.5±1.7 vs. 41.9±0.6, PsION: We found that layperson age >62 years and female gender are associated with shallower CC depth.

关键词： Cardiac arrest Cardiopulmonary resuscitation Bystander CPr quality Layperson Demographics

A GmNINa-mir172c-NNC1 regulatory Network Coordinates the Nodulation and Autoregulation of Nodulation Pathways in soybean

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Molecular Plant 2019年第9期12卷 1211-1226页

作者： Lixiang Wang Zhengxi sun Chao su Yongliang Wang Qiqi Yan Jiahuan Chen Thomas.ott Xia Li state Key Laboratory of Agricultural Microbiology College of Plant Science and TechnologyHuazhong Agricultural UniversityNo.1 Shizishan RoadHongshan DistrictWuhanHubei 430070P.R.China College of Biological science and Engineering Panzhihua UniversityNo.10 Airport RoadEastern DistrictPanzhihuaSichuanChina University of Freiburg.Faculty of Biology.University of Freiburg Schdnz丨estrasse 179104 Freiburg.Germany CIBss-Centre for Integrative Biological signalling studies University of Freiburg79104 FreiburgGermany

symbiotic root nodules are root lateral organs of plants in which nitrogen-fixing bacteria(rhizobia)convert atmospheric nitrogen to *** formation and number of nodules in legumes are precisely controlled by a rhizobia-induced signal cascade and host-controlled autoregulation of nodulation(AON).However,how these pathways are integrated and their underlying mechanisms are ***,we report that microrNA172c(mir172c)activates soybean(Glycine max)r hizobia-induced CLE1(GmrICI)and GmrIC2 by removing the transcriptional repression of these genes by Nodule Number Control 1(NNC1),leading to the activation of the AON ***1 interacts with GmNINa,the soybean ortholog of Lotus NODULE INCEPTION(NIN),and hampers its transcriptional activation o i G m rICI and ***,GmNINa acts as a transcriptional activator of ***,NNC1 can transcriptionally repress mir172c expression,adding a negative feedback loop into the NNC1 regulatory ***,GmNINa interacts with NNC1 and can relieve the NNC1-mediated repression of mir172c ***,the GmNINa-mir172c-NNC1 network is a master switch that coordinately regulates and optimizes NF and AON signaling,supporting the balance between nodulation and AON in soybean.

关键词： nodule number autoregulation of nodulation mir172c-NNC1 negative feedback loop nodule inception

sildenafil does not influence hepatic venous pressure gradient in patients with cirrhosis

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World Journal of Gastroenterology 2008年第40期14卷 6208-6212页

作者： Jens.otto Clemmesen Annamaria Giraldi Peter ott Kim Dalhoff Bent Adel Hansen Fin stolze Larsen Department of Hepatology RigshospitaletUniversity Hospital of Copenhagen Clinical Pharmacology RigshospitaletUniversity Hospital of Copenhagen

AIM： To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient （HVPG） in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liver disease. However, the effect of phosphodiesterase type-5 inhibitors on splanchnic blood flow and portal hypertension remains essentially unknown. METHODs： Ten patients with biopsy proven cirrhosis （five females/five males, mean age 54：1：8 years） and an HVPG above 12 mmHg were studied after informed consent. Measurement of splanchnic blood flow and the HVPG during liver vein catheterization were done before and 80 min after oral administration of 50 mg sildenafil. Blood flow was estimated by use of indocyanine green clearance technique and Fick＇s principle, with correction for non-steady state. rEsULTs： The plasma concentration of sildenafil was 222 ± 136 ng/mL 80 min after administration. Mean arterial blood pressure decreased from 77 ±7 mmHg to 66 ± 12 mmHg, P = 0.003, while the splanchnicblood flow and oxygen consumption remained unchanged at 1.14 ± 0.71 L/min and 2.3 ± 0.6 mmol/ min, respectively. Also the HVPG remained unchanged （18 ± 2 mmHg vs 16 ± 2 mmHg） with individual changes ranging from -8 mmHg to ±2 mmHg. In seven patients, HVPG decreased and in three it increased. CONCLUsION： In spite of arterial blood pressure decreases 80 min after administration of the phosphodiesterase type-5 inhibitor sildenafil, the present study could not demonstrate any clinical relevant influence on splanichnic blood flow, oxygen consumption or the HVPG.

关键词： Cirrhosis sildenafil Portal hypertension Portal hemodynamics Hepatic blood flow Erectile dysfunction Hepatic venous pressure gradient

reduced Vector Helmholtz Wave Equation Analysis on the Wave-Number side

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Journal of Electromagnetic Analysis and Applications 2019年第9期11卷 161-172页

作者： randy ott retired researcher Albuquerque NM USA

The resolvent helps solve a PDE defined on all of wave-number space, . Almost all electromagnetic scattering problems have been solved on the spatial side and use the spatial Green’s function approach. This work is motivated by solving an EM problem on the Fourier side in order to relate the resolvent and the Green’s function. Methods used include Matrix Theory, Fourier Transforms, and Green’s function. A closed form of the resolvent is derived for the electromagnetic Helmholtz reduced vector wave equation, with Dirichlet boundary conditions. The resolvent is then used to derive expressions for the solution of the EM wave equation and provide sobolev estimates for the solution.

关键词： Helmholtz em Vector Wave Equation Closed form of resolvent sobolev Estimates for solution