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seasonal biostabilization and erosion behavior of fluvial biofilms under different hydrodynamic and light conditions

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International j.urnal of sediment Research 2015年第04期30卷 273-284页

作者： Moritz thom Holger schmidt sabine U.Gerbersdorf silke Wieprecht Institute for Modelling Hydraulic and Environmental systems Department of Hydraulic Engineering and Water Resources ManagementUniversity of Stuttgart

Biofilm growth may considerably influence the erodibility of river bed sediments and is,thus,an important morphological *** extent to which the sediment is stabilized depends on many environmental conditions and even though it is well accepted that these conditions are responsible for the variance of results obtained from field studies,little is known about their impact on *** this article,the results from five long-term(4-8 weeks) experiments are presented,investigating the impact of hydrodynamics and light intensity on biostabilization in different *** are cultivated in a sophisticated setup of six identical straight flumes by circulating natural river water over glass beads with diameters between 0.1 and 0.2 *** the course of the experiments biofilm samples are eroded regularly to determine the critical shear stress and to learn more about the erosional behavior of biostabilized *** results indicate a large variance of biostabilization between seasons with the highest values in spring and the lowest in late ***,this is explained by the differences in biofilm growth and composition resulting in mechanically diverse responses to the increased bed shear *** bed shear stress during cultivation delayed biofilm growth possibly due to reduced net attachment and growth of formerly advected microbes on the sediment ***,no substantial biostabilization effect is detected in experiments where biofilms are cultivated in *** focus in this article is the analysis of the mechanical behavior observed during erosion of the biofilms,that is shown to be an important aspect for the understanding of freshwater biostabilization caused by young growing biofilms.

关键词： Biofilm Critical bed shear stress Erosion mechanisms Environmental conditions seasonal variations

Le reflet de la sagesse chinoise

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今日中国（法文版） 2022年第8期60卷 34-36页

作者： LARs ULRIK thom Beij.ng Postcards

Eliza scidmore,une j.urnaliste du National Geographie,avait visité Beij.ng en *** n'avait pas tari d’éloges sur 20 pages pour présenter Beij.ng sous tous les *** que j.ai trouvé curieux,c'est que nulle part ell... 详细信息

关键词： let j.urnal pour

Dual-functional porous and cisplatin-loaded polymethylmethacrylate cement for reconstruction of load-bearing bone defect kills bone tumor cells

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Bioactive Materials 2022年第9期7卷 120-130页

作者： Zhule Wang Liebert Parreiras Nogueira Håvard j.stein Haugen Ingrid CM.Van Der Geest Patricia Caetano de Almeida Rodrigues Dennis j.nssen thom Bitter j.roen j.j.P.van den Beucken sander CG.Leeuwenburgh Radboud University Medical Center Department of Dentistry-Regenerative BiomaterialsRadboud Institute for Molecular Life SciencesNijmegenthe Netherlands University of Oslo Department of BiomaterialsInstitute of Clinical DentistryFaculty of DentistryOsloNorway Radboud University Medical Center Department of OrthopedicsRadboud Institute for Health SciencesNijmegenthe Netherlands

Malignant bone tumors are usually treated by resection of tumor tissue followed by filling of the bone defect with bone graft ***(PMMA)cement is the most commonly used bone substitute in clinical orthopedics in view of its ***,the dense nature of PMMA renders this biomaterial unsuitable for local delivery of chemotherapeutic drugs to limit the recurrence of bone ***,we introduce porosity into PMMA cement by adding carboxymethylcellulose(CMC)to facilitate such local delivery of chemotherapeutic drugs,while retaining sufficient mechanical properties for bone reconstruction in load-bearing *** results show that the mechanical strength of PMMA-based cements gradually decreases with increasing CMC *** incorporation of≥3%CMC,the PMMA-based cements released up to 18%of the loaded cisplatin,in contrast to cements containing lower amounts of CMC which only released less than 2%of the cisplatin over 28 *** release of cisplatin efficiently killed osteosarcoma cells in vitro and the fraction of dead cells increased to 91.3%at day 7,which confirms the retained chemotherapeutic activity of released cisplatin from these PMMA-based ***,tibias filled with PMMA-based cements containing up to 3%of CMC exhibit comparable compressive strengths as compared to intact *** conclusion,we demonstrate that PMMA cements can be rendered therapeutically active by introducing porosity using CMC to allow for release of cisplatin without compromising mechanical properties beyond critical *** such,these data suggest that our dual-functional PMMA-based cements represent a viable treatment option for filling bone defects after bone tumor resection in load-bearing sites.

关键词： Porous polymethylmethacrylate cement Bone tumor treatment Local drug delivery Chemotherapeutic drug Ex vivo biomechanical assessment

Improving cover and management factor (C-factor) estimation using remote sensing approaches for tropical regions

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International soil and Water Conservation Research 2019年第4期7卷 325-334页

作者： André Almagro Thais Caregnatto thomé Carina Barbosa Colman Rodrigo Bahia Pereira j.sé Marcato j.nior Dulce Buchala Bicca Rodrigues Paulo Tarso sanches Oliveira Federal University of Mato Grosso do sul CxP 549 Campo Grande MS 79070-900 Brazil

The Revised Universal soil Loss Equation (RUsLE)'s cover and management factor (C-factor) is one of the most difficult factors to obtain,mainly because long-term monitoring soil erosion plots under natural rainfall are ***,remote sensing approaches have been used as an alternative for obtaining this ***,there is a lack of studies comparing values of this factor computed from remote sensing approaches with measured *** this study,we compare two widely used remote sensing approaches (CrA and CVK) to estimate the C-factor based on the Normalized Difference Vegetation Index (NDVI) with the literature (CLIT) and field experimental data..We also investigated the influence of C-factor methods on the prediction of soil loss and sediment yield (sY) using measured data in the Guariroba basin,Central-West *** obtained mean C-factor values of 0.032,0.023 and 0.137 for CLIT,CrA and CVK,*** found an average annual soil loss of 2.20 tha-1 yr-1,2.02 t ha-1 yr-1 and 10.07 tha-1 yr-1 and sY values of 6875 tyr-1,6468 tyr-1 and 33,435 t yr1,for CLIT,CrA and CVK *** results indicated a significant improvement in soil loss and sY estimations by using the CrA approach developed for tropical regions,with a bias of 13% to the measured sY (5709tyr-1).We conclude that the CrA method present the most suitable alternative to compute soil loss and sY in tropical ***,this approach allows large-scale evaluation and temporal monitoring,therefore enhancing multi spatial and temporal assessment of soil erosion processes.

关键词： soil erosion RUsLE NDVI Landsat 8 Land use/land cover

Metastasis to Paranasal sinuses as the First Presenting sign of Renal Cell Carcinoma

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Open j.urnal of Urology 2012年第1期2卷 28-31页

作者： Gustavo Ruschi Bechara j.sé Anacleto Dutra Resende j.nior Hélio Assuncao Gouveia thom.s Accioly de souza Department of Urology Hospital Federal da Lagoa Rio de Janeiro Brazil

The clear cell carcinoma is a relatively rare tumor, represented approximately 85% by renal cell carcinoma (RCC), but has a characteristic of early metastatic, which sometimes spread to unusual places. Metastatic tumors in the paranasal sinuses are very rare. This case report a 65 years-old patient who presented sinusitis and epitaxis as a first sign of renal cell carcinoma with metastasis to the right maxillary sinus, which was opereted at Lagoa Hospital—Rj.and strengthen the inclusion of this disease in the differential diagnosis of sinus disease. The renal cell carcinoma is a relatively rare tumor, representing approximately 3% of malignant tumors. About a third of patients with renal cell carcinoma have metastasis at diagnosis. The sinuses are a rare location of metastasis. The maxillary sinuses and the paranasal sinuses are most commonly affected by metastatic tumors to the sinuses region. The most frequent primary tumor to metastasis to paranasal sinuses is the renal cell carcinoma. This report highlights the rarity of the case and the importance in the differential diagnosis of sinus disease.

关键词： Renal Cell Carcinoma Metastasis sinuses Epistaxis

Assessing adequacy of emergency provider documentation among interhospital transferred patients with acute aortic dissection

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World j.urnal of Emergency Medicine 2019年第2期10卷 94-100页

作者： Mark Rose Carina Newton Benchaa Boualam Nancy Bogne Adam Ketchum Umang shah j.rdan Mitchell safura Tanveer Tucker Lurie Walesia Robinson Rebecca Duncan stephen thom Quincy Khoi Tran Department of Emergency Medicine University of Maryland School of Medicine University of Maryland at College Park University of Maryland School of Medicine Program of Trauma The R Adams Cowley Shock Trauma Center University of Maryland School of Medicine

BACKGROUND: Acute aortic dissection(AoD) is a hypertensive emergency often requiring the transfer of patients to higher care hospitals; thus, clinical care documentation and compliance with the Emergency Medical Treatment and Active Labor Act(EMTALA) is crucial. The study assessed emergency providers(EP) documentation of clinical care and EMTALA compliance among interhospital transferred AoD ***: This retrospective study examined adult patients transferred directly from a referring emergency department(ED) to a quaternary academic center between j.nuary 1, 2011 and september 30, 2015. The primary outcome was the percentage of records with adequate documentation of clinical care(ADoCC). The secondary outcome was the percentage of records with adequate documentation of EMTALA compliance(ADoEMTALA). REsULTs: There were 563 electronically identified patients with 287 included in the final analysis. One hundred and five(36.6%) patients had ADoCC while 166(57.8%) patients had ADoEMTALA. Patients with inadequate documentation of EMTALA(IDoEMTALA) were associated with a higher likelihood of not meeting the American Heart Association(AHA) ED Departure sBP guideline(OR 1.8, 95% CI 1.03–3.2, P=0.04). Male gender, handwritten type of documentation, and transport by air were associated with an increased risk of inadequate documentation of clinical care(IDoCC), while receiving continuous infusion was associated with higher risk of ***: Documentation of clinical care and EMTALA compliance by Emergency Providers is poor. Inadequate EMTALA documentation was associated with a higher likelihood of patients not meeting the AHA ED Departure sBP guideline. Therefore, Emergency Providers should thoroughly document clinical care and EMTALA compliance among this critically ill group before transfer.

关键词： Acute aortic dissection EMTALA Interhospital transfer Documentation Compliance

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案例教学法——一种很有效的环境教育方式

环境教育 2001年第4期 22-23页

作者： thom j.McEvoy 美国佛蒙特大学自然资源学院

在教师进行有关环境知识的教学时，经常将学生作为听众，把知识记忆当成是目标，但这样做，很可能丧失了更富有教育意义的“思维过程”，这一过程的意义在于：教师可以有效地培养学生分析问题的方法、技能和态度，而这些宝贵的东西也正... 详细信息

在教师进行有关环境知识的教学时，经常将学生作为听众，把知识记忆当成是目标，但这样做，很可能丧失了更富有教育意义的“思维过程”，这一过程的意义在于：教师可以有效地培养学生分析问题的方法、技能和态度，而这些宝贵的东西也正是通过学生自己的参与实现的。下面介绍的案例教学法无疑为大家开启了一扇能有效促进学生学习角色转变和参与方法训练的新窗口。

关键词：案例教学法环境教育方式教学方法

No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes

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Forest Ecosystems 2024年第3期11卷 255-265页

作者： j.ayun Zou Yahuang Luo Rupert seidl Dominik thom j.e Liu Lisa Geres Tobias Richter Linj.ang Ye Wei Zheng Liangliang Ma j.e song Kun Xu Dezhu Li Lianming Gao sebastian seibold Ecosystem Dynamics and Forest Management Research Group School of Life SciencesTechnical University of MunichHans-Carl-von-Carlowitz-Platz 285354FreisingGermany state Key Laboratory of Plant Diversity and specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina Germplasm Bank of Wild species Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina Lij.ang Forest Biodiversity National Observation and Research station Kunming Institute of BotanyChinese Academy of SciencesLijiang674100China Berchtesgaden National Park Doktorberg 683471Germany Gund Institute for Environment University of Vermont617 Main StreetBurlingtonVT 1105405USA Faculty of Biological sciences Institute for EcologyEvolution and DiversityConservation BiologyGoethe University FrankfurtFrankfurt am MainGermany University of Chinese Academy of sciences Beijing10049China TUD Dresden University of Technology Forest ZoologyPienner Str.701737TharandtGermany

An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity *** stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable ***,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different *** study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical *** quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic *** elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across *** found no general pattern of BPRs across landscapes and *** were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical *** were largely congruent between taxonomic,functional and phylogenetic *** found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical *** temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific *** effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across *** study highlights the context-dependence of BPRs across elevation gradients and *** traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of ***,our findings highlight that potential trade-offs be

关键词： Biodiversity-ecosystem functioning Climate mitigation Elevation gradients Forest management Forest productivity Functional traits Nature conservation Phylogenetic diversity

Impacts of land use and land cover changes on hydrological processes and sediment yield determined using the sWAT model

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International j.urnal of sediment Research 2022年第1期37卷 54-69页

作者： Edivaldo Afonso de Oliveira serr?o Madson Tavares silva thom.s Rocha Ferreira Lorena Concei??o Paiva de Ataide Cleber Assis dos santos Aline Maria Meiguins de Lima Vicente de Paulo Rodrigues da silva Francisco de Assis salviano de sousa Denis j.sé Cardoso Gomes Academic Unit of Atmospheric sciences Federal University of Campina Grande Department of Physics Center for Natural and Exact Sciences Federal University of Santa Maria Institute of Technology Civil Engineering Graduate Program Federal University of Pará Earth system science Center National Institute of Space Research Institute of Geosciences Federal University of Pará

Land use and land cover (LULC) changes strongly affect local hydrology and sediment *** current study focused on a basin in the Brazilian Amazon and had the following three obj.ctives:(1) to perform an effective diagnosis of flow and sediment yield,(2) to evaluate the impacts of LULC changes over the last 40 years on the hydro-sedimentological variables,and (3) to investigate the impacts of the possible trends or breaking points in the flow,surface runoff,and sediment yield *** soil and Water Assessment Tool (sWAT) model validation showed that the simulated results were consistent with the data measured in the dynamic reproduction of flow ***,changes in LULC altered surface runoff,sediment yield,and flow according to the Mann-Kendall and Pettitt non-parametric *** was also observed that the sub-basins in which pastureland is predominant are more susceptible to increased surface runoff and sediment *** to trend and homogeneity tests,these sub-basins had break points in the time series of these *** the other hand,in the sub-basins whose land cover is predominantly forest,the time series is homogeneous and *** current study highlighted the impacts that 40 years of LULC changes in an Amazonian basin had on hydro-sedimentological variables,which,in turn,can play an important role in changing the hydrological cycle,consequently these changes can also impact diverse human activities in the region,such as agribusiness,livestock,energy production,food security,and public water ***,it is concluded that the sWAT model is a good estimator of hydro-sedimentological processes in Amazonian basins and can be used by decision makers in the management of water and environmental resources.

关键词： Hydrological modeling sediment yield Amazon basin sWAT model