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Many public urban parks, but who profits from them? The example of Tabriz, Iran

Ecological Processes 2015年第1期4卷 72-86页

作者： jürgen Breuste Akbar Rahimi Research Group for Urban and Landscape Ecology Department of Geography and GeologyUniversity of SalzburgSalzburgAustria Department of Landscape Engineering University of TabrizBolvare 29 BahmanTabrizIran

Introduction:Public urban parks are accessible to everyone in a *** time people need to reach a public park influences the accessibility of the *** far away from home are less accessible because of time to spend to reach them than those in the *** green urban infrastructure aims to provide different types of parks(by size and structure)to all urban *** network of parks should allow all inhabitants to have access to parks within close proximity to their ***:This paper aims to investigate the accessibility of parks as related to the social status of the *** was investigated using the example of a clearly socially stratified city(Tabriz,Iran),in which a part of the urban society(by total number and social status)has better or worse access to urban *** example of urban parks shows which services are supplied on site and who the potential users are within an accessible *** services are qualified by structural park indicators and quantified by the quantity of these *** distances are calculated on the basis of the size of the *** distance circles around the parks indicate from where most of the users are coming,depending on park category.A quantification of population as related to potential users by social status in different distances to the parks shows the accessibility of parks for different quantities of inhabitants and different social *** classification of social status(high,middle,and low)was carried out by General Census of statistical center in 2005,informal settlement project data,statistical blocks data,land price in Tabriz municipality,and master and detailed plan ***:Many households do not enjoy government recommended levels of access to public green spaces in Tabriz,and the results highlight the social segregation in park distribution and their ***:The best parks are located in the high social status areas,and the acce

关键词： Ecological services Urban parks Social status Park accessibility

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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

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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

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 407-424页

作者： M.SAFI M.VAKILIFARD M.j.MAHMOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of Mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin j.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

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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

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Developing a new agenda for increased food and climate security

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 35-54页

作者： William j.DAVIES Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK

In many countries, political and environmental pressures are currently combining to generate a perfect storm of circumstances that is reducing food availability, increasing food costs and thereby reducing the availability of food to many. The UK is currently considering new national food and land management policies, and attention is also being given to legislation to address diet-related health issues. Many now argue for a revolution in UK farming practices to reduce their impact on the natural environment. The UK is not alone in facing these and other challenges. Both the contribution of agriculture to greenhouse gas(GHG) emissions and the effects of climate change on food production are issues receiving worldwide *** agricultural practices can result in greater C capture, reduced GHG emissions, enhanced soil quality and enhanced biodiversity. However, it is questioned if such farming systems will be productive enough to feed a growing population with the food required for social and health benefits. To fully exploit the impact of new plant science in farmer fields, it is imperative to effectively link science to farming practices and conduct a broader conversation around the food revolution with social scientists and with the general public.

关键词： Climate resilience food security human health planetary health regenerative agriculture

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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

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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

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The innate immune system in Parkinson's disease:a novel target promoting endogenous neuroregeneration

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Neural Regeneration Research 2015年第5期10卷 704-706页

作者： johannes CM Schlachetzki jürgen Winkler Department of Molecular Neurology Friedrich-AlexanderUniversity (FAU) Erlangen-Nürnberg University Hospital Erlangen

Parkinson＇s disease （PD） is a slowly progressing neuro- degenerative disorder clinically defined by key symptoms like bradykinesia, rigidity, resting tremor, and postural instability. Reduction of dopaminergic terminals in the caudate nucleus and putamen, i.e., the striatum, accom- panied by decreased striatal levels of dopamine, and most likely consecutive degeneration of dopaminergic neurons in the substantia nigra pars compacta （SNpc） are tightly linked to the onset of the motor symptoms. With the etiology of PD largely not yet well defined, there is accu- mulating evidence for increased immune activation in PD. The majority of studies favor a detrimental effect of microglia, the resident innate immune cells of the brain, on PD pathogenesis. In the presence of alpha-synuclein, inflammatory responses elicited by microglia may be initiated by pattern recognition receptors, e.g.,

关键词： SVZ GFAP PD

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