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Modelling stratified forest attributes using optical/LiDAR features in a central European landscape

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International Journal of Digital Earth 2012年第2期5卷 106-132页

作者： Hooman Latifi Arne Nothdurft Christoph Straub Barbara koch Department of Remote Sensing and Landscape Information Systems University of FreiburgTennenbacherstraßeFreiburgGermany Department of Biometry and Informatics Forest Research Institute Baden WurttembergWonnhaldestraßeFreiburgGermany

Improvements in the acquisition of three-dimensional(3D)information from the Airborne Laser Scanner(ALS)increase its applications for studying Earth’s *** use of ALS data in natural resource inventories is still in an experimental stage in central ***,a survey was completed in Germany,where plot-level features from LANDSAT Thematic Mapper and ALS data were *** automated process was developed for forest stratification using orthoimages.A genetic algorithm was applied for variable *** subsets of different sizes were employed for simultaneous predictions of structural forest attributes using the‘Random Forest’(RF)*** was assessed by leave-one-out cross-validations on bootstrap resample *** indicate that the stratification of forest notably improved the results of *** improvements were more obvious for the strata-related *** was enhanced as the number of selected variables ***,parsimonious models are still essentially required for practical *** RF errors were slightly greater than those from least squares regression,as the non-parametric methods do not share the same mix of error components as *** the combination of remote sensing and modelling,we conclude that our results are helpful for bridging the gap between regional earth observation and on-the-ground forest structure.

关键词： spatial prediction natural resource inventory ALS Digital Earth data fusion remote sensing

Plant Surfaces:Structures and Functions for Biomimetic Innovations

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Nano-Micro Letters 2017年第2期9卷 116-155页

作者： Wilhelm Barthlott Matthias Mail Bharat Bhushan Kerstin koch Nees Institute for Biodiversity of Plants Rheinische Friedrich-Wilhelms University of BonnVenusbergweg 2253115 BonnGermany Institute of Crop Science and Resource Conservation(INRES)–Horticultural Science Rheinische Friedrich-Wilhelms University of BonnAuf dem Hugel 653121 BonnGermany

An overview of plant surface structures and their evolution is presented. It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications. Within some 3.5 billion years biological species evolved highly complex multifunctional surfaces for interacting with their environments: some 10 million living prototypes(i.e., estimated number of existing plants and animals) for engineers. The complexity of the hierarchical structures and their functionality in biological organisms surpasses all abiotic natural surfaces: even superhydrophobicity is restricted in nature to living organisms and was probably a key evolutionary step with the invasion of terrestrial habitats some 350–450 million years ago in plants and insects. Special attention should be paid to the fact that global environmental change implies a dramatic loss of species and with it the biological role models. Plants, the dominating group of organisms on our planet, are sessile organisms with large multifunctional surfaces and thus exhibit particular intriguing *** and superhydrophobicity are focal points in this work. We estimate that superhydrophobic plant leaves(e.g., grasses) comprise in total an area of around 250 million km^2, which is about 50% of the total surface of our planet. A survey of structures and functions based on own examinations of almost 20,000 species is provided, for further references we refer to Barthlott et al.(Philos. Trans. R. Soc. A 374: 20160191, 1). A basic difference exists between aquatic nonvascular and land-living vascular plants; the latter exhibit a particular intriguing surface chemistry and architecture. The diversity of features is described in detail according to their hierarchical structural order. The first underlying and essential feature is the polymer cuticle superimposed by epicuticular wax and the curvature of single cells up to complex multicellular structures. A descriptive terminology for t

关键词： Bionics Superhydrophobicity Hierarchical structuring Lotus effect Salvinia effect Evolution

Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

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Journal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris koch Kenneth J.Reimer Environmental Sciences Group Royal Military College of Canada

Fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a major compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the major arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus Fungi HPLC-ICP-MS XAS imaging

Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation

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Asian Journal of Andrology 2012年第3期14卷 436-450,I0007页

作者： Teodora Ribarska Klaus-Marius Bastian Annemarie koch Wolfgang A Schulz Department of Urology Heinrich Heine University 40225 Duesseldorf Germany 1

Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 （EZH2） overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 （IGF2）. A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.

关键词： androgen signalling imprinted genes loss of imprinting PI3K signalling prostate cancer

DISPERSION RELATION AND LANDAU LEVELS OF INVERSION LAYER SUBBAND ON p-HgCdTe

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Science China Mathematics 1990年第10期33卷 1192-1200页

作者：褚君浩 R.SIZMANN F.koch National Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 PRC Physik-Department E-16 T. U. München D-8046 Garching F. R. Germany

Starting from Kane's model and taking into account the surface electron spin-orbit interaction, we have derived the dispersion relation and Landau levels of inversion layer subband on narrow-gap semiconductors. The capacitance-voltage spectroscopy, magnetoconductivity oscillations and cyclotron resonance spectroscopy for the p-Hg_(1-x)Cd_x Te MIS structure sample at temperature 4.2 K have been measured. From the experimental data, the subband parameters and spin-orbit coupling intensity, which are involved in the expressions of subband dispersion relation and Landau levels, have been determined. As a result, the inversion layer electron subband dispersion relation and Landau level fan chart for HgCdTe as well as the zero field spin splitting effect, the shifting and the crossing effect of Landau levels have been described quantitatively.

关键词： narrow-gap semiconductors HgCdTe 2-dimensional electron gas subband Landau level.

Evidence for maternal transmission of a putative endosymbiont in the digestive gland of Pomacea canaliculata(Architaenioglossa,Ampullariidae)

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BIOCELL 2017年第2期41卷 59-61页

作者： EDUARDO koch ISRAEL A.VEGA ALFREDO CASTRO-VAZQUEZ Departamento de Biología Universidad Nacional de CuyoFacultad de Ciencias Exactas y Naturales Instituto Argentino de Investigaciones de las Zonas Aridas(IADIZA-CCT-Mendoza) Instituto de Fisiología Universidad Nacional de CuyoFacultad de Ciencias Médicas IHEM Universidad Nacional de CuyoCONICET

The digestive gland of the apple snail Pomacea canaliculata lodges two types of pigmented corpuscles(identified as C and K corpuscles)which has been proposed as endosymbiont/*** corpuscular types are always present in the digestive gland of adult snails,they are released into the tubuloacinar lumen and are later expelled in the *** their part,hatchlings lack any C or K corpuscles in the digestive gland as well as in their feces,whereas C corpuscles appear in both the gland and feces within one week after ***,it is possible that the detritivorous hatchlings acquire the putative C-endosymbiont from feces in the sediments where they live,***‘lateral’or‘horizontal’*** possibility was put to test in an experiment in which we prevented any lateral transmission,by a 7-days aseptic culture,with no food,of aseptically obtained *** the end of the experiment,we observed that most juveniles had survived the culture period,and hence the digestive glands and feces of survivors were studied by light microscopy of resin embedded,toluidine blue-stained *** studied glands and fecal samples showed C *** is concluded that lateral transmission of the endosymbiont,if any,is not indispensable for the acquisition of the endosymbiont by hatchlings.

关键词： Pigmented corpuscles Ampullariidae Endosymbiosis Coevolution

Organization of future training in bariatric gastroenterology

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World Journal of Gastroenterology 2017年第35期23卷 6371-6378页

作者： Timothy R koch Timothy R Shope Christopher J Gostout Center for Advanced Laparoscopic General and Bariatric Surgery Med Star Washington Hospital Center and Georgetown University School of Medicine Division of Gastroenterology and Hepatology Mayo Clinic

A world-wide rise in the prevalence of obesity continues. This rise increases the occurrence of, risks of, and costs of treating obesity-related medical conditions. Diet and activity programs are largely inadequate for the long-term treatment of medically-complicated obesity. Physicians who deliver gastrointestinal care after completing traditional training programs, including gastroenterologists and general surgeons, are not uniformly trained in or familiar with available bariatric care. It is certain that gastrointestinal physicians will incorporate new endoscopic methods into their practice for the treatment of individuals with medically-complicated obesity, although the longterm impact of these endoscopic techniques remains under investigation. It is presently unclear whether gastrointestinal physicians will be able to provide or coordinate important allied services in bariatric surgery, endocrinology, nutrition, psychological evaluation and support, and social work. Obtaining longitudinal results examining the effectiveness of this ad hoc approach will likely be difficult, based on prior experience with other endoscopic measures, such as the adenoma detection rates from screening colonoscopy. As a longterm approach, development of a specific curriculum incorporating one year of subspecialty training in bariatrics to the present training of gastrointestinal fellows needs to be reconsidered. This approach should be facilitated by gastrointestinal trainees' prior residency training in subspecialties that provide care for individuals with medical complications of obesity, including endocrinology, cardiology, nephrology, and neurology. Such training could incorporate additional rotations with collaborating providers in bariatric surgery, nutrition, and psychiatry. Since such training would be provided in accredited programs, longitudinal studies could be developed to examine the potential impact on accepted measures of care, such as complication rates, outcomes, and

关键词： Obesity Bariatrics Bariatric surgery Intragastric balloon Endoscopic sleeve gastroplasty Nutrition Endoscopy Training

The German Transplant Certification

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Hepatobiliary Surgery and Nutrition 2024年第2期13卷 382-386页

作者： Björn Nashan Utz Settmacher Martina koch The Transplantation Center First Affiliated HospitalSchool of Life Sciences and Medical CenterUniversity of Sciences&Technology of ChinaHefeiChina Department of General Visceral and Vascular SurgeryJena University HospitalJenaGermany General Visceraland Transplantation SurgeryUniversity Medical CenterMainzGermany

Since the inception of solid organ transplantation through the 50s and 60s of the 20th century,transplantation has evolved into a major driver not only in the field of surgery,but immunology,pharmacology,pathology,internal medicine,providing new techniques and concepts to provide services for patients,that had been doomed to succumb to their acute or chronic *** surgeons not only developed surgical techniques but were drivers in the development of immunosuppression as well as the inclusion of other specialties into multidisciplinary teams.

关键词： Education in transplantation board certification interdisciplinary curriculum German Transplant Certification

Current and future impact of clinical gastrointestinal research on patient care in diabetes mellitus

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World Journal of Diabetes 2018年第11期9卷 180-189页

作者： Timothy R koch Timothy R Shope Michael Camilleri Center for Advanced Laparoscopic General and Bariatric Surgery MedStar Washington Hospital Center and Georgetown University School of Medicine Division of Gastroenterology and Hepatology Mayo Clinic

The worldwide rise in the prevalence of obesity supports the need for an increased interaction between ongoing clinical research in the allied fields of gastrointestinal medicine/surgery and diabetes mellitus. There have been a number of clinically-relevant advances in diabetes, obesity, and metabolic syndrome emanating from gastroenterological research. Gastric emptying is a significant factor in the development of upper gastrointestinal symptoms. However, it is not the only mechanism whereby such symptoms occur in patients with diabetes. Disorders of intrinsic pacing are involved in the control of stomach motility in patients with gastroparesis; on the other hand, there is limited impact of glycemic control on gastric emptying in patients with established diabetic gastroparesis. Upper gastrointestinal functions related to emptying and satiations are significantly associated with weight gain in obesity. Medications used in the treatment of diabetes or metabolic syndrome, particularly those related to pancreatic hormones and incretins affect upper gastrointestinal tract function and reduce hyperglycemia and facilitate weight loss. The degree of gastric emptying delay is significantly correlated with the weight loss in response to liraglutide, a glucagonlike peptide-1 analog. Network meta-analysis shows that liraglutide is one of the two most efficacious medical treatments of obesity, the other being the combination treatment phentermine-topiramate. Interventional therapies for the joint management of obesity and diabetes mellitus include newer endoscopic procedures, which require long-term follow-up and bariatric surgical procedure for which long-term follow up shows advantages for individuals with diabetes. Newer bariatric procedures are presently undergoing clinical evaluation. On the horizon, combination therapies, in part directed at gastrointestinal functions, appear promising for these indications. Ongoing and future gastroenterological research when translate

关键词： Obesity Gastric emptying Diabetes mellitus Gastric bypass Bariatric surgery Weight loss