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Risk excess measures induced by hemi-metrics

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Probability, Uncertainty and Quantitative Risk 2018年第1期3卷 175-209页

作者： Olivier P.Faugeras Ludger Ruschendorf Toulouse School of Economics-Universite Toulouse 1 Capitole Manufacture des Tabacs21 All´ee´de Brienne31000 ToulouseFrance Abteilung fur Mathematische Stochastik Albert-Ludwigs University of FreiburgEckerstrasse 1¨D-79104 FreiburgGermany

The main aim of this paper is to introduce the notion of risk excess measure,to analyze its properties,and to describe some basic construction *** compare the risk excess of one distribution Q w.r.t.a given risk distribution P,we apply the concept of hemi-metrics on the space of probability *** view of risk comparison has a natural basis in the extension of orderings and hemi-metrics on the underlying space to the level of probability *** examples of these kind of extensions are induced by mass transportation and by function class induced *** view towards measuring risk excess adds to the usually considered method to compare risks of Q and P by the valuesρ(Q),ρ(P)of a risk measureρ.We argue that the differenceρ(Q)−ρ(P)neglects relevant aspects of the risk excess which are adequately described by the new notion of risk excess *** derive various concrete classes of risk excess measures and discuss corresponding ordering and measure extension properties.

关键词： Risk measure Mass transportation Hemi-metric Stochastic order

A flexible protruding microelectrode array for neural interfacing in bioelectronic medicine

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Microsystems & Nanoengineering 2022年第6期8卷 165-179页

作者： Helen Steins Michael Mierzejewski Lisa Brauns Angelika Stumpf Alina Kohler Gerhard Heusel Andrea Corna Thoralf Herrmann Peter d.Jones Günther Zeck Rene von Metzen Thomas Stieglitz NMI Natural and Medical Sciences Institute at the University of Tübingen ReutlingenGermany Laboratory for Biomedical Microtechnology Department of Microsystems EngineeringUniversity of FreiburgFreiburgGermany Institute of Biomedical Electronics TU WienViennaAustria Bernstein Center freiburg University of FreiburgFreiburgGermany BrainLinks-BrainTools University of FreiburgFreiburgGermany

Recording neural signals from delicate autonomic nerves is a challenging task that requires the development of a lowinvasive neural interface with highly selective,micrometer-sized *** paper reports on the development of a three-dimensional(3d)protruding thin-film microelectrode array(MEA),which is intended to be used for recording low-amplitude neural signals from pelvic nervous structures by penetrating the nerves transversely to reduce the distance to the *** gold pillars(O 20 or 50μm,~60μm height)were fabricated on a micromachined polyimide substrate in an electroplating *** sidewalls were insulated with parylene C,and their tips were optionally modified by wet etching and/or the application of a titanium nitride(TiN)*** microelectrodes modified by these combined techniques exhibited low impedances(~7 kΩ at 1 kHz for ∅ 50μm microelectrode with the exposed surface area of~5000μm^(2))and low intrinsic noise *** functionalities were evaluated in an ex vivo pilot study with mouse retinae,in which spontaneous neuronal spikes were recorded with amplitudes of up to 66μ*** novel process strategy for fabricating flexible,3d neural interfaces with low-impedance microelectrodes has the potential to selectively record neural signals from not only delicate structures such as retinal cells but also autonomic nerves with improved signal quality to study neural circuits and develop stimulation strategies in bioelectronic medicine,e.g.,for the control of vital digestive functions.

关键词： neural microelectrode electronic

Stochastic equations for a self-regulating gene

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International Journal of Biomathematics 2017年第4期10卷 1-29页

作者： Martin Jansen University Medical Center freiburg Institute of Clinical Chemistry and Laboratory Medicine Hugstetter Str. 55 D-79106 Freiburg Germany

Expression of cellular genes is regulated by binding of transcription factors to their promoter, either activating or inhibiting transcription of a gene. Particularly interesting is the case when the expressed protein regulates its own transcription. In this paper, the features of this self-regulating process are investigated. In the presented model here, the gene can be in two states. Either a protein is bound to its promoter or not. The steady state distributions of protein during and just before switching from one state to the next state are analyzed. Moreover, a powerful numerical method based on the corresponding master equation to compute the protein distribution in the steady state is presented and compared to an already-existing method. Additionally the special case of self-regulation, in which protein can only be produced, if one of these proteins is bound to the promoter region, is analyzed. Furthermore, a self-regulating gene is compared to a similar gene, which also has two states and produces the same amount of proteins but is not regulated by its protein-product.

关键词： Gene expression chemical reaction network activated gene gene regulatorynetworks master equation.

SURFACE　INTEGRAL　OF　THREE－dIMENSIONAL　VELOCITY　FIELd　FOR　SQUARE　BAR　dRAWING　THROUGH　CONICAL　dIE

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中国有色金属学会会刊：英文版 1996年第3期6卷 131-135页

作者： Zhao, dW Guo, CW Liu, XH Fang, YK NORTHEASTERN UNIV ROLLING TECHNOL & TANDEM ROLLING AUTOMAT NATL KEY SHENYANG 110006 PEOPLES R CHINA UNIV freiburg INST ANGEW MATH D-7800 FREIBURG GERMANY

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关键词： square bar drawing three dimensional velocity field surface integral

Hepatitis B virus-induced oncogenesis

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World Journal of Gastroenterology 2007年第1期13卷 74-81页

作者： Joachim Lupberger Eberhard Hildt department of Internal Medicine II Hugstetter Str. 55 D-79106 Freiburg Germany

Hepatocellular carcinoma (HCC) is one of the most com- mon cancers in the world with an annual incidence of more than 500 000 in the year 2000. Its incidence is rising in many countries. Recently, it has been estimated that about 53% of HCC cases in the world are related to hepatitis B virus (HBV). The epidemiological association of HBV with HCC is well established. In recent studies, it was revealed that HBsAg carriers have a 25-37 times increased risk of developing HCC as compared to non-infected people. At present, HBV-associated carcinogenesis can be seen as a multi-factorial process that includes both direct and indirect mechanisms that might act synergistically. The integration of HBV dNA into the host genome occurs at early steps of clonal tumor expansion. The integration has been shown in a number of cases to affect a variety of cancer- related genes and to exert insertional mutagenesis. The permanent liver inflammation, induced by the immune response, resulting in a degeneration and regeneration process confers to the accumulation of critical mutations in the host genome. In addition to this, the regulatory proteins HBx and the PreS2 activators that can be encoded by the integrate exert a tumor promoter-like function resulting in positive selection of cells producing a functional regulatory protein. Gene expression profiling and proteomic techniques may help to characterize the molecular mechanisms driving HBV-associated carcino- genesis, and thus potentially identify new strategies in diagnosis and therapy.

关键词： Hepatitis B virus Hepatocellular carcinoma Regulatory proteins Signal transduction

Extracellular matrices for gastrointestinal surgery:Ex vivo testing and current applications

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World Journal of Gastroenterology 2010年第32期16卷 4031-4038页

作者： Jens Hoeppner Goran Marjanovic Peter Helwig Ulrich Theodor Hopt Tobias Keck department of General and Visceral Surgery University of FreiburgFreiburg 79106Germany department of Orthopedics and Traumatology University of FreiburgFreiburg 79106Germany

AIM:To assess the effects of bile and pancreatic juice on structural and mechanical resistance of extracellular matrices(ECMs) in ***:Small-intestinal submucosa(SIS),porcine dermal matrix(PdM),porcine pericardial matrix(PPM) and bovine pericardial matrix(BPM) were incubated in human bile and pancreatic juice in *** were examined by macroscopic observation,scanning electron microscopy(SEM) and testing of mechanical ***:PdM dissolved within 4 d after exposure to bile or pancreatic ***,PPM and PdM retained their integrity for > 60 d when incubated in either digestive *** effect of bile was found to be far more detrimental to mechanical stability than pancreatic juice in all tested *** SIS,the loss of mechanical stability after incubation in either of the digestive secretions was less distinct than in PPM and BPM [mFmax 4.01/14.27 N(SIS) vs 2.08/5.23 N(PPM) vs 1.48/7.89 N(BPM)].In SIS,the extent of structural damage revealed by SEM was more evident in bile than in pancreatic *** PPM and BPM,structural damage was comparable in both ***:PdM is less suitable for support of gastrointestinal *** SIS,PPM and BPM should also be evaluated experimentally for gastrointestinal indications.

关键词： Extracellular matrix Intestinal regeneration Ex-vivo testing Gastrointestinal surgery Gastrointestinal fistula Bioscaffolding

Growth and form of Quercus robur and Fraxinus excelsior respond distinctly different to initial growing space: results from 24-year-old Nelder experiments

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Journal of Forestry Research 2013年第1期24卷 1-14页

作者： Christian Kuehne Patrick Pyttel Edgar Kublin Jürgen Bauhus Institute of Silviculture University of FreiburgD-79085 Freiburg i.Br.Germany. Faculty of Forests and Forestry University of Applied Sciences Wei- henstephan-TriesdorfHans-Carl-von-Carlowitz-Platz 3D-85354 FreisingGermany department of Biometry and Informatics Forest Research Station Baden-WürttembergPostfach 708D-79007 FreiburgGermany

Initial growing space is of critical importance to growth and quality development of individual trees. We investigated how mortality, growth （diameter at breast height, total height）, natural pruning （height to first dead and first live branch and branchiness） and stem and crown form of 24-year-old pedunculate oak （Quercus robur [L.]） and European ash （Fraxinus excelsior [L.]） were affected by initial spacing. data were recorded from two replicate single-species Nelder wheels located in southern Germany with eight initial stocking regimes varying from 1,020 to 30,780 seedlings·ha？1. Mortality substantially decreased with increasing initial growing space but significantly differed among the two species, averaging 59% and 15% for oak and ash plots, respectively. In contrast to oak, the low self-thinning rate found in the ash plots over the investigated study period resulted in a high number of smaller intermediate or suppressed trees, eventually retarding individual tree as well as overall stand development. As a result, oak gained greater stem dimensions throughout all initial spacing regimes and the average height of ash significantly increased with initial growing space. The survival of lower crown class ashes also appeared to accelerate self-pruning dynamics. In comparison to oak, we observed less dead and live primary branches as well as a smaller number of epicormic shoots along the first 6 m of the lower stem of dominant and co-dominant ashes in all spacing regimes. Whereas stem form of both species was hardly affected by initial growing space, the percentage of brushy crowns significantly increased with initial spacing in oak and ash. Our findings suggest that initial stockings of ca. 12,000 seedlings per hectare in oak and 2,500 seedlings per hectare in ash will guarantee a sufficient number of at least 300 potential crop trees per hectare in pure oak and ash plantations at the end of the self-thinning phase, respectively. If the problem of epicormic shoots a

关键词： spacing trial stocking self-thinning intraspecific competition qualification spatially explicit modelling generalized additive model

Impact of Elevated PCO2 on Mass Flow of Reduced Nitrogen in Trees

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Journal of Integrative Plant Biology 2006年第12期48卷 1385-1390页

作者： Xi-Ping Liu College of Life Sciences of Northwest Sci-Tech University of Agriculture and Forestry 712100 Yangling China Institute of Forest Botany and Tree Physiology University of Freiburg D-79110 Freiburg Germany

To analyze the effects of elevated carbon dioxide concentration （PCO2） on the mass flow of reduced nitro- gen （N） in the phloem and xylem of trees, juvenile beech （Fagus sylvatica L.） and spruce （Picea abies （L.） Karst.） were grown in phytotrons and exposed to ambient and elevated PCO2 （plus 687.5 mg/m^3 CO2） for three growing seasons. Elevated PCO2 significantly decreased the mass flow of N from the shoot to roots of beech by significantly reducing the concentration of soluble amino compounds in the phloem, even if the area of conductive phloem of cross-sectional bark tissue was significantly increased, because of less callus deposition in the sieve elements. In spruce, the downward mass flow of reduced N also tended to be decreased, similar to that in beech. Resembling findings in the phloem, N mass flow from roots to shoot in both tree species was significantly diminished owing to significantly reduced concentrations of amino compounds in the xylem and a lower transpiration rate. Therefore, the mass flow of reduced N between shoots and roots of trees was mainly governed by the concentrations of soluble amino compounds in the phloem and xylem in relation to the loading of reduced N in both long-distance transport pathways.

关键词： beech elevated PCO2 nitrogen mass flow phloem spruce xylem.

Recuperation of severe tumoral calcinosis in a dialysis patient: A case report

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World Journal of Clinical Cases 2019年第23期7卷 4004-4010页

作者： Lukas Westermann Lisa K Isbell Marie K Breitenfeldt Frederic Arnold Elvira Rothele Johanna Schneider Eugen Widmeier department of Medicine IV Medical CenterUniversity of FreiburgFaculty of MedicineUniversity of FreiburgFreiburg 79106Germany department of Medicine I Medical CenterUniversity of FreiburgFaculty of MedicineUniversity of FreiburgFreiburg 79106Germany dialysis Center freiburg Freiburg 79100Germany

BACKGROUNd One of the common late sequela in patients with end-stage renal disease(ESRd)is the calcium phosphate disorder leading to chronic hypercalcemia and hyperphosphatemia causing the precipitation of calcium salt in soft *** calcinosis is an extremely rare clinical manifestation of cyst-like soft tissue deposits in different periarticular regions in patients with ESRd and is characterized by extensive calcium salt containing space-consuming painful *** treatment of ESRd patients with tumoral calcinosis manifestation involves an increase in or switching of renal replacement therapy regimes and the adjustment of oral medication with the goal of improved hypercalcemia and *** SUMMARY We describe a 40-year-old woman with ESRd secondary to IgA-nephritis and severe bilateral manifestation of tumoral calcinosis associated with hypercalcemia,hyperphosphatemia and tertiary *** patient was on continuous ambulatory peritoneal dialysis and treatment with vitamin d *** switching her to a daily hemodialysis schedule and adjusting the medical treatment,the patient experienced a significant dissolution of her soft tissue calcifications within a couple of *** remission was achieved 11 mo after the initial *** Reduced patient compliance and subsequent insufficiency of dialysis regime quality contribute to the aggravation of calcium phosphate disorder in a patient with ESRd leading to the manifestation of tumoral ***,the improvement of the treatment strategy and reinforcement of patient compliance enabled complete remission of this rare disease entity.

关键词： End-stage renal disease Renal replacement therapy-dialysis Hyperparathyroidism Hypercalcemia Hyperphosphatemia Tumoral calcinosis Case report