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A Generalized Discrete Morse-Floer Theory

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Communications in Mathematics and Statistics 2019年第3期7卷 225-252页

作者： jürgen jost Sylvia Yaptieu Max Planck Institute for Mathematics in the Sciences Inselstrasse 2204103 LeipzigGermany Santa Fe Institute for the Sciences of Complexity Santa FeNM 87501USA

Forman has developed a version of discrete Morse theory that can be understood in terms of arrow patterns on a(simplicial,polyhedral or cellular)complex without closed orbits,where each cell may either have no arrows,receive a single arrow from one of its facets,or conversely,send a single arrow into a cell of which it is a *** following arrows,one can then construct a natural Floer-type boundary ***,we develop such a construction for arrow patterns where each cell may support several outgoing or incoming arrows(but not both),again in the absence of closed *** main technical achievement is the construction of a boundary operator that squares to 0 and therefore recovers the homology of the underlying complex.

关键词： CW complex Boundary operator Floer theory Poincarépolynomial Betti number Discrete Morsetheory Discrete Morse-Floertheory Conleytheory

Molecular elements of pheromone detection in the female moth, Hefiothis virescens

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Insect Science 2018年第3期25卷 389-400页

作者： Monika Zielonka Heinz Breer jürgen Krieger Institute of Physiology University of Hohenheim Stuttgart Germany Department of Animal Physiology Institute of BiologylZoology Martin Luther University Halle-Wittenberg Halle (Saale) Germany

Pheromones play pivotal roles in the reproductive behavior of moths, most prominently for the mate finding of male moths. Accordingly, the molecular basis for the detection of female-released pheromones by male moths has been studied in great detail. In contrast, little is known about how females can detect pheromone components released by themselves or by conspecifics. In this study, we assessed the antenna of female Helio- this virescens for elements of pheromone detection. In accordance with previous findings that female antennae respond to the sex pheromone component （Z）-9-tetradecenal, we identified olfactory sensory neurons that express its cognate receptor, the receptor type HR6. All HR6 cells coexpressed the ＂sensory neuron membrane protein 1＂（SNMP1） and were associated with supporting cells expressing the pheromone-binding proteins PBP1 and PBP2. These features are reminiscent to male antennae and point to congruent mechanisms for pheromone detection in the two sexes. Further analysis of the SNMP1- expressing cells revealed a higher number in females compared to males. Moreover, in females, the SNMP 1 neurons were arranged in clusters, which project their dendrites into a common sensillum, whereas in males there were only solitary SNMPl-neurons and only 1 per sensillum. Not all SNMP1 positive cells in female antennae expressed HR6 but instead the putative pheromone receptors HR11 and HR18, respectively. Neurons express- ing 1 of the 3 receptor types were assigned to different sensilla. Together the data indicate that on the antenna of females, sensory neurons in a subset of sensilla trichodea are equipped with molecular elements, which render them responsive to pheromones.

关键词： female insect moth olfaction pheromone detection

Decomposition dynamics of coarse woody debris of three important central European tree species

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Forest Ecosystems 2015年第4期2卷 339-352页

作者： Steffen Herrmann Tiemo Kahl jürgen Bauhus Institute of Forest Sciences Faculty of Environment and Natural ResourcesUniversity of Freiburg Swiss Federal Research Institute WSL

Background： Coarse woody debris （CWD） is an important element of forest structure that needs to be considered when managing forests for biodiversity, carbon storage or bioenergy. To manage it effectively dynamics of CWD decomposition should be known. Methods： Using a chronosequence approach, we assessed the decomposition rates of downed CWD of Fagus sylvatica, Picea obies and Pinus sylvestfis, which was sampled from three different years of tree fall and three different initial diameter classes （〉10 - ≤20 cm, 〉20 - ≤40 cm, 〉40 cm）. Samples originating from wind throws in 1999 were collected along a temperature and precipitation gradient. Based on the decay class and associated wood densities, log volumes were converted into CWD mass and C content. Log fragmentation was assessed over one year for log segments of intermediate diameters （〉20 - 40 cm） after 8 and 18 years of decomposition. Results： Significantly higher decomposition constants （k） were found in logs of F. sylvotica （0.054 year^-1） than in P. abies （0.033 year^-1） and P. sylvestris （0.032 year^-1）. However, mass loss of P. sylvestris occurred mainly in sapwood and hence k for the whole wood may be overestimated. Decomposition rates generally decreased with increasing log diameter class except for smaller dimensions in P. obies. About 74 % of the variation in mass remaining could be explained by decomposition time （27 %）, tree species （11%）, diameter （17 %）, the interactive effects between tree species and diameter （4 %） as well as between decomposition time and tree species （3 %） and a random factor （site and tree; 9.5 %）, whereas temperature explained only 2 %. Wood fragmentation may play a more important role than previously thought. Here, between 14 % and 30 % of the decomposition rates （for the first 18 years） were attributable to this process. Carbon （C） density （mgC· cm ^-3）, which was initially highest for F. sylvatico, followed by P. sylvestris and P. obies, decreased with increasing decay stage t

关键词： Dead wood Carbon Decay rate Beech Spruce Pine

Long-term monitoring of PCDD/PCDF and other unintentionally produced POPs-Concepts and case studies from Europe

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Science China Chemistry 2010年第5期53卷 1017-1024页

作者： REINMANN jürgen WEBER Roland HAAG Roland Environnement S.A Deutschland Benzstrasse 1161352 Bad HomburgGermany POPs Environmental Consulting Ulmenstraβe 373035 GppingenGermany TüV Süd Industrie Service GmbH Grabenwiesenstraβe 473072 DonzdorfGermany

During the start-up and unstable combustion periods,even the state-of-the-art incinerators emit polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/PCDF) in stack gases at concentrations that are up to 1000 times higher than normal operation. Therefore,incinerators and other sources with variation of PCDD/PCDF release into air cannot be reliably monitored by the conventional short-term sampling that covers only 0.1%to 0.2%of the yearly operating time.A more comprehensive monitoring regime is *** paper describes different applications of continuous PCDD/PCDF sampling in some European *** cases demonstrate that flexible regimes for continuous sampling can be crafted and applied by governments or regional/local *** regimes range from a countrywide,continuous requirement for selected facility types(e.g.,waste incinerators) to a facility-specific regime that applies,for example,to new facilities for a defined time period until the facility has demonstrated continuous compliance with regulatory limits. Countries implementing the Stockholm Convention are suggested to evaluate in their Best available technology/Best environmental practice(BAT/BEP) activities the usefulness of long-term sampling by,for example,designating institutes related to the environmental ministry or regional authorities to supervise long-term sampling regimes at relevant facilities in their country/areas,beginning with priority sources(e.g.,facilities used for destruction of persistent organic pollutants(POPs) or hazardous waste processing) . This paper presents and discusses the results of the AMESA long-term monitoring system having demonstrated that in addition to PCDD/PCDF all other unintentionally produced POPs listed in the Stockholm Convention could be supervised.

关键词： PCDD/PCDF PCB continuous sampling unintentionally produced POPs Stockholm Convention BAT/BEP

Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany

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Forest Ecosystems 2019年第3期6卷 249-260页

作者： Felix Storch Gerald Kadler jürgen Bauhus Chair of Silviculture University of FreiburgD-79085 FreiburgGermany Department of Biometry Forest Research Institute of Baden-WürttembergD-79100 FreiburgGermany

Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002-2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%-90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity.

关键词： Large-scale inventory Structural diversity index Harvesting intensity Changes in structural diversity

Tracing the failing heart: dual genetic fate mapping for target identification

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Signal Transduction and Targeted Therapy 2023年第9期8卷 3880-3882页

作者： Yaw Asare Christian Stoppe jürgen Bernhagen Institute for Stroke and Dementia Research(ISD) Klinikum der Universität München(KUM)Ludwig-Maximilian-University(LMU)81377 MunichGermany Department of Anesthesiology Intensive CareEmergency and Pain MedicineUniversity Hospital Würzburg97080 WürzburgGermany Department of Cardiac Anesthesiology and Intensive Care Medicine German Heart Center CharitéBerlin13353 BerlinGermany Munich Cluster for Systems Neurology 81377 MunichGermany Munich Heart Alliance 80802 MunichGermany

In a recent study published in Nature Genetics,1 Han and colleagues employed a dual genetic lineage tracing approach in combination with a model of heart failure(HF)to identify a key sub-population of endocardium-derived fibroblasts,which gives rise to excessive myofibroblast formation in a Wnt pathway-mediated manner and contributes to cardiac fibrosis.1 The identified fibroblast sub-population and Wnt signaling pathway could be novel targets for the therapy of *** in risk management and cardiovascular inter-vention have significantly reduced age-specific cardiovascular disease-related *** contrast,the rate of HF-related hospitalisations has increased over the past decades and HF is a disease with highest social and economic cost in industrialized *** is defined as impairment of the heart’s blood pumping function and its severity is assessed based on ejection *** often occurs after myocardial infarction(MI),with infarct size and quality of ventricular remodeling after MI influencing ventricular *** of HF also include hypertension,atrial fibrillation,and cardiomyopathies(Fig.1).Especially elderly patients with recurrent MI and comorbidities are increasingly presenting with signs of HF.

关键词： cardiovascular ventricular mortality

Stand dynamics of the drought-affected floodplain forests of Araguaia River,Brazilian Amazon

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Forest Ecosystems 2017年第3期4卷 201-210页

作者： jürgen Homeier Dariusz Kurzatkowski Christoph Leuschner Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen

Background： The floodplain forests of Araguaia River, a clear-water river in the southeastern Amazon（Tocantins State, Brazil）, are characterized by seasonal flooding up to 3.5 m height, low nutrient levels in the water, and seasonal drought periods of 4–5 ***： We studied the forest dynamics（tree diameter growth, tree mortality and recruitment） of this unique forest ecosystem over a 5-year period by repeated censuses in 12 permanent plots established along a flooding ***： The cumulative basal area in the plots increased by 0.84（±0.45） m^2·ha^-1·yr^-1（mean ±SD） in the annual y-flooded（AF） plots in lower terrain and by 0.69（±1.00） m^2·ha^-1·yr^-1 in the higher non-annual y flooded（NAF） plots, corresponding to an aboveground biomass increase of 0.81（±0.57） and 0.69（±1.58） Mg·ha^-1·yr^-1 in the AF and NAF plots, indicating a recent carbon sink in the biomass. Mean diameter growth rate was 1.8（±0.44） mm·yr^-1 in the AF and 2.0（±0.56） mm·yr^-1 in the NAF plots（corresponding to a coarse wood production of 1.53（±1.29） and 2.02（±0.52） Mg·ha^-1·yr^-1）,indicating no flooding effect on radial growth. Mean mortality rates in the 5-year period were 1.9（±0.37）·yr^-1 in the AF plots and 1.8（±0.87）%·yr^-1 in the NAF plots with no differences along the flooding gradient. Highest mortalities were registered in the AF plots for the 10–20 cm dbh class（2.4%·yr^-1）, likely as a consequence of flooding,and in the NAF plots for the 40–50 cm dbh class（3.0%·yr^-1）, probably mainly caused by ENSO-related ***： We conclude that these drought-affected tropical floodplain forests have a lower standing biomass and aboveground productivity than central Amazonian floodplain forests in more humid climates, and the imprint of the flooding gradient on stand dynamics is relatively weak, which may result from the lower flooding height and the interaction of flooding with low nutrient supply and periodic drought.

关键词： Amazon Diameter growth Dry season Flooding regime Mortality rate Productivity Tree recruitment

Prevention of gob ignitions and explosions in longwall mining using dynamic seals

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International journal of Mining Science and Technology 2017年第6期27卷 999-1003页

作者： Brune jürgen F. Saki Saqib A. Department of Mining Engineering Colorado School of Mines CO 80401 USA Aldea Services LLC Frederick MD 21704 USA

Most, if not all longwall gob areas accumulate explosive methane-air mixtures that pose a deadly hazard to miners. Numerous mine explosions have originated from explosive gas zones(EGZs) in the longwall gob. Since 2010, researchers at the Colorado School of Mines(CSM) have studied EGZ formation in longwall gobs under two long-term research projects funded by the National Institute for Occupational Safety and Health. Researchers used computational fluid dynamics along with in-mine measurements. For the first time, they demonstrated that EGZs form along the fringe areas between the methane-rich atmospheres and the fresh air ventilated areas along the working face and present an explosion and fire hazard to mine workers. In this study, researchers found that, for progressively sealed gobs, a targeted injection of nitrogen from the headgate and tailgate, along with a back return ventilation arrangement, will create a dynamic seal of nitrogen that effectively separates the methane zone from the face air and eliminates the EGZs to prevent explosions. Using this form of nitrogen injection to create dynamic seals should be a consideration for all longwall operators.

关键词： Mine explosions Face ignitions Coal mining Longwall mining Methane

Harnessing naturally occurring mutations for T-cell therapy:a potential new avenue to enhance treatment efficacy

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1799-1801页

作者： Michael Hiltensperger jürgen Ruland Kilian Schober Mikrobiologisches Institut-Klinische Mikrobiologie Immunologie und HygieneFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Institute of Clinical Chemistry and Pathobiochemistry School of MedicineTechnical University of MunichMunichGermany TranslaTUM Center for Translational Cancer ResearchTechnical University of MunichMunichGermany German Cancer Consortium(DKTK) HeidelbergGermany German Center for Infection Research(DZIF) partner site MunichMunichGermany FAU Profile Center Immunomedicine Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

In a recent study published in Nature,Garcia et *** a sophisticated approach to identify fitness-enhancing mutations for T cells that was inspired by cancer evolution.1 The identified CARD11-PIK3R3 gene fusion enhanced tumor rejection and persistence of engineered T cells in multiple tumor models and might have the potential to improve efficacy of adoptive T-cell therapies in cancer patients.

关键词： cancer potential