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Harvesting of forest products and implications for Afrotemperate bird communities in a montane forest of the Eastern cape, South Africa

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Forest Ecosystems 2019年第4期6卷 352-366页

作者： Jessica Leaver johann c.carstens Michael I.cherry Department of Botany and Zoology Stellenbosch University

Background: Harvesting of forest products is a widespread driver of disturbance in developing nations, where policies are increasingly aimed at managing natural forests for sustainable use. There is thus need for research aimed at understanding the impact of resource use on forest habitats and concomitant effects on *** forests in the Eastern cape, South Africa are harvested informally for poles and medicinal bark and occur along elevational gradients of 800–1600 m above sea level. Patterns of spatial diversity and human disturbance are expected to be affected by elevation. Furthermore, species’ responses to disturbance are expected to vary depending on their level of habitat specialisation. Understanding harvest impacts on forest biodiversity thus requires disentangling the separate effects of elevation and disturbance, and considering forest-specialist and forest-generalist species separately. This study comprises two components. First, harvest activities, resultant harvestmediated habitat heterogeneity, and avifaunal species richness, composition and beta-diversity were compared across two elevational zones in a harvested forest. Second, the role of harvest-mediated habitat heterogeneity in driving patterns of avifaunal diversity were assessed, while controlling for elevation, and considering forest-specialist and forest-generalist species ***: Harvest rates were higher, and activities more varied in the lower elevation zone, with significant impacts of harvesting on habitat features resulting in higher harvest-mediated habitat heterogeneity at lower ***-mediated increases in habitat heterogeneity positively affected forest-generalist species richness, while forest-specialist richness was negatively affected. While species composition of both groups differed across elevational zones, variation in harvest-mediated habitat heterogeneity did not fully account for this, suggesting that factors other than disturbance

关键词： Human disturbance Habitat heterogeneity Habitat modification Beta-diversity Elevation Generalist species Forest-specialist species

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超细粉掺合料专用聚羧酸减水剂的制备及性能研究

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新型建筑材料 2024年第1期51卷 49-53,64页

作者：谢瑞兴于奂泽岳光亮唐樱燕彭立刚于彭 johann Plank 山东众森新材料有限公司山东济南250000 北京王府学校北京102209 山东众森科技股份有限公司山东济南250000 德国慕尼黑工业大学德国慕尼黑80539

为解决超细粉掺合料在混凝土应用中出现的黏度大、流速时间长、易抓底、收缩大的问题,通过合成原料的选择以及调整合成工艺,合成了超细掺合料专用聚羧酸减水剂ZS-cX。结果表明,采用EPEG单体、合成起始温度15℃、滴加反应时间60 min,MAP... 详细信息

为解决超细粉掺合料在混凝土应用中出现的黏度大、流速时间长、易抓底、收缩大的问题,通过合成原料的选择以及调整合成工艺,合成了超细掺合料专用聚羧酸减水剂ZS-cX。结果表明,采用EPEG单体、合成起始温度15℃、滴加反应时间60 min,MAP用量为单体质量的0.6%时,制备的减水剂性能最佳。与市售减水剂相比,净浆流动度、混凝土坍落度和扩展度增大,倒筒排空时间更短,达到5 s,Zeta电位绝对值大,而且混凝土60 d电通量小于1000 c、收缩率降低30%以上。

关键词：超细粉掺合料聚羧酸减水剂合成混凝土性能

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On the structure in the ΛN cross section at the ∑N threshold

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chinese Physics c 2021年第9期45卷 157-166页

作者： johann Haidenbauer Uf-G.MeiBner Institute for Advanced Simulation Institut fur Kemphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Helmholtz-Institut fiir Strahlen-und Kemphysik and Bethe center for Theoretical Physics Universitat Bonn53115 BonnGermany Tbilisi State University 0186 TbilisiGeorgia

The complexity of threshold phenomena is exemplified on a prominent and long-known case-the structure in theΛp cross section(invariant mass spectrum)at the opening of the∑N *** mass splitting between the∑baryons together with the angular momentum coupling in the^(3)S_(1)-^(3)D_(1)partial wave imply that,in principle,up to six channels are *** hyperon-nucleon potentials that provide an excellent description of the available low-energy Λp and∑N scattering data,the shape of the resulting Λp cross section is discussed and the poles near the ∑N threshold are *** for a strangeness S=-1 dibaryon is provided,in the form of a(unstable)∑N bound state in the vicinity of the ∑N *** for level shifts and widths of ∑^(-)p atomic states are given.

关键词： hyperon-nucleon interaction dibaryon threshold effects

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Neutron-antineutron oscillations in the deuteron studied with NN and ■N interactions based on chiral effective field theory

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chinese Physics c 2020年第3期44卷 28-32页

作者： johann Haidenbauer Ulf-G.Meiβner Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany Helmholtz-Institut für Strahlen-und Kernphysik and Bethe center for Theoretical Physics Universität Bonn53115 BonnGermany Tbilisi State University 0186 TbilisiGeorgia

Neutron-antineutron(n−n)oscillations in the deuteron are ***,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and *** reasons for the difference are discussed.

关键词： neutron-antineutron oscillations chiral effective field theory NN interaction antinucleon-nucleon interaction

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The phylogeny of francolins(Francolinus, Dendroperdix, Peliperdix and Scleroptila) and spurfowls(Pternistis) based on chick plumage(Galliformes: Phasianidae)

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Avian Research 2018年第1期9卷 1-18页

作者： johann H.van Niekerk Tshifhiwa G.Mandiwana-Neudani Department of Environmental Sciences College of Agriculture and Environmental ScienceUniversity of South Africa Department of Biodiversity University of Limpopo

Background: This paper describes the chick plumage of spurfowl(Pternistis) and francolin(Francolinus, Dendroperdix Peliperdix and Scleroptila) chicks, tests its significance for phylogenetic relationships and also explores the patterns of character evolution in the francolin and spurfowl *** regarded as monophyletic, the two evolutionar?ily distant clades are now divided into five *** considered were whether chick plumage supports the dichotomy between spurfowls and francolins and what role habitat matching ***: The study was based mainly on photographs of chick skins from the American Museum of Natural History and the Natural History Museum at *** plumage characters were selected for comparative scoring, summa?rised in a *** characters were subsequently analysed phylogenetically and their evolution was traced on the existing molecular phylogeny using a parsimony ***: Based on chick plumage the phylogeny of species groups among francolins and spurfowls, was largely unresolved possibly ascribed to a high degree of symplesiomorphy inherent among the *** possibly could have resulted in a high degree of polytomy particularly among the spurfowls and ***, the ancestral state reconstructions revealed high prevalence of symplesiomorphic states and reversals which do not help in the classification of *** the differences are described that separate some African francolins from spurfowls, other francolins(in Asia and Africa) share remarkably similar characteristics with *** dark dorsal plumage is probably advantageous for avoiding detection by predators in forests, while facial stripes optimise the breaking of body shapes in dense grass cover(as in Scleroptila spp.) and semi?striped faces are advantageous for stationary camouflage under tree and bush cover(as in Pternistis spp.).conclusions: Although symplesiomorphy is a hereditary explanation for downy c

关键词： Spurfowl Francolin Phasianidae chick plumage Phylogeny Ancestral state reconstruction Habitat

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Tumor–stromal cross-talk modulating the therapeutic response in pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 461-472页

作者： christopher c.M.Neumann Ellen von Horschelmann Anja Reutzel-Selke Elisabeth Seidel Igor Maximilian Sauer johann Pratschke Marcus Bahra Rosa Bianca Schmuck Department of Surgery Campus Charité Mitte Campus Virchow-KlinikumExperimental SurgeryCharité-Universitatsmedizin BerlinBerlinGermany Berlin Institute of Health Department of SurgeryCampus CharitéMitte and Campus Virchow-KlinikumAugustenburger Platz 113353 BerlinGermany

Background: Pancreatic ductal adenocarcinoma(PDAc) is a highly malignant solid tumor with a dismal prognosis. The stroma component makes up to 90% of the tumor mass and is thought to be one of the main reasons for the tumor’s high chemoresistance. cancer associated fibroblasts(cAFs) have previously been identified to be the key stromal players. This is the first time we provide detailed in vitro experiments investigating tumor–stromal interactions when exposed to three well-known chemotherapeutic agents. Methods: Monocultures, indirect and direct co-cultures of two PDAc cell lines(AsPc and Panc-1) and six primary patients derived cAFs were treated with gemcitabine, nab-paclitaxel and the γ-secretaseinhibitor(GSI) DAPT. The cell viability of each component was measured with XTT. Finally, IL-6 concentrations of the supernatants were analyzed. Results: On the contrary to PDAc cell lines, cAF monocultures hardly responded to any treatment which suggested that stroma(cAFs) itself is more resistant to standard chemo-treatments than the epithelial cancer cells. Moreover, only a weak chemotherapeutic response was observed in direct co-cultures of cancer cells with cAFs. A change in the morphology of direct co-cultures was accompanied with the chemoresistance. cAFs were observed to build cage-like structures around agglomerates of tumor cells. High levels of IL-6 were also associated with a reduced response to therapy. Indirect co-cultures make the tumor–stromal interaction more complex. conclusions: cAFs are highly chemoresistant. Direct cell–cell contact and high levels of IL-6 correlate with a high chemoresistance.

关键词： Pancreatic cancer Tumor microenvironment cancer associated fibroblasts cancer–stroma co-culture Atroma targeted therapy

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“Autoinflammatory psoriasis”-genetics and biology of pustular psoriasis

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cellular & Molecular Immunology 2021年第2期18卷 307-317页

作者： Ranjitha Uppala Lam c.Tsoi Paul W.Harms Bo Wang Allison c.Billi Emanual Maverakis J.Michelle Kahlenberg Nicole L.Ward johann E.Gudjonsson Graduate Program in Immunology University of MichiganAnn ArborMIUSA Department of Dermatology University of MichiganAnn ArborMIUSA Department of Pathology University of MichiganAnn ArborMIUSA Department of Dermatology University of CaliforniaDavisSacramentoCAUSA Division of Rheumatology Department of Internal MedicineUniversity of MichiganAnn ArborMIUSA A.Alfred Taubman Medical Research Institute Ann ArborMIUSA Departments of Nutrition and Dermatology Case Western Reserve UniversityClevelandOHUSA

Psoriasis is a chronic inflammatory skin condition that has a fairly wide range of clinical *** psoriasis,which is the most common manifestation of psoriasis,is located on one end of the spectrum,dominated by adaptive immune responses,whereas the rarer pustular psoriasis lies on the opposite end,dominated by innate and autoinflammatory immune *** recent years,genetic studies have identified six genetic variants that predispose to pustular psoriasis,and these have highlighted the role of IL-36 cytokines as central to pustular psoriasis *** this review,we discuss the presentation and clinical subtypes of pustular psoriasis,contribution of genetic predisposing variants,critical role of the IL-36 family of cytokines in disease pathophysiology,and treatment perspectives for pustular *** further outline the application of appropriate mouse models for the study of pustular psoriasis and address the outstanding questions and issues related to our understanding of the mechanisms involved in pustular psoriasis.

关键词： Pustular psoriasis Genetics IL-36 Autoinflammation clinical features Histology

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Increased chemical reactivity of single-walled carbon nanotubes on oxide substrates： In situ imaging and effect of electron and laser irradiations

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Nano Research 2016年第2期9卷 517-529页

作者： Hasan-al Mehedi johann Ravaux Khadija Yazda Thierry Michel Said Tahir Michael Odorico Renaud Podor Vincent Jourdain Laboratoire charles coulomb (L2c) UMR 5221 CNRS-Universite de Montpellier 34095 Mon tpellier France Institut de chimie Separative de Marcoule UMR 5257 CEA-CNRS-UM2-ENSCM Site de Marcoule Bat 426 BP 17171 30207 Bagnols sur Ceze cedex France

We studied the oxygen etching of individual single-walled carbon nanotubes on silicon oxide substrates using atomic force microscopy and high-temperature environmental scanning electron microscopy. Our in situ observations show that carbon nanotubes are not progressively etched from their ends, as frequently assumed, but disappear segment by segment. Atomic force microscopy, before and after oxidation, reveals that the oxidation of carbon nanotubes on substrates proceeds through a local cutting that is followed by a rapid etching of the disconnected nanotube segment. Unexpectedly, semiconducting nanotubes appear more reactive under these conditions than metallic ones. We also show that exposure to electron and laser beams locally increases the chemical reactivity of carbon nanotubes on such substrates. These results are rationalized by considering the effect of substrate-trapped charges on the nanotube density of states close to the Fermi level, which is impacted by the substrate type and the exposure to electron and laser beams.

关键词： single-walled carbon nanotubes environmental scanning electron microscopy oxidative etching substrate-trapped charges electron and laser irradiations

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Reappraisal of glucocorticoids in castrate-resistant prostate cancer

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Asian Journal of Andrology 2014年第5期16卷 666-666页

作者： Oliver Sartor christopher c Parker johann de Bono Department of Urology and Medicine Tulane MedicalSchool Tulane New Orleans Louisiana USA Department of Urology The Royal Marsden NHSFoundation Trust Sutton UK

Recent reports and discussions of .preclinical prostate cancer models have emphasized the possibility that enzalutamide resistance may be mediated by glucocorticoid receptors （GR）.In both in vitro and xenograft animal studies, it is possible to show that the GR is up-regulated in prostate cancer cell lines and that dexamethasone reverses enzalutamide induced growth inhibition. In these model systems, GR agonists can induce a subset of androgen receptor target genes including prostate-specific antigen. These investigators also report a correlation between GR expression in patient-derived prostate cancer specimens and clinical response to enzalutamide. The authors discuss the possibility that these findings have important clinical relevance. We note that the current clinical evidence for GR mediating drug resistance or disease progression in patients with castrate-resistant prostate cancer （cRPc） is very limited at best.

关键词： Reappraisal glucocorticoids castrate-resistant

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Performances of local poultry breed fed black soldier fly larvae reared on horse manure

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Animal Nutrition 2018年第1期4卷 73-78页

作者： Nassim Moula Marie-Louise Scippo caroline Douny Guy Degand Edwin Dawans Jean-Francois cabaraux Jean-Luc Hornick Rudy c.Medigo Pascal Leroy Frederic Francis johann Detilleux Fundamental and Applied Research for Animal&Health Animal Production DepartmentFaculty of Veterinary MedicineUniversity of Liege Fundamental and Applied Research for Animal&Health Food Science DepartmentFaculty of Veterinary MedicineUniversity of Liege Functional and Evolutionary Entomology Gembloux Agro-Bio TechUniversity of Liege

In poultry,feed based on maggots,like larvae of black soldier fly(Hermetia illucens) is an attractive option to substitute current ingredients which are expensive and often in direct or indirect competition with human *** information is currently available on the utility of these larvae in poultry feed,so goals of this study were to determine whether larvae could be reared on horse manure under traditional farming conditions and to evaluate the growth performances of a local poultry fed these larvae and the fatty acids profiles of their *** freezing and thawing,larvae were introduced in the feed of Ardennaise chickens between 30 and 80 days of *** in the control group received a commercial standard feed,while those in the treatment group received the same commercial feed in which 8% was substituted with whole fresh larvae corresponding to 2% on a dry matter *** ± standard errors of larval length and weight were 20.67 ± 2.21 mm and 0.14 ± 0.02 g,*** larval percentages of dry matter and of substances extractable in diethyl ether were 24.6% and 23.1%,*** fatty acids profiles were predominantly composed of lauric acid(28.1%) and palmitic acid(22.0%).Least squares means of weekly weights of chicken,adjusted for the effects of sex,replication and initial weights,were significantly higher(P control *** other measurements were not statistically different between larvae-fed and control chicken,including fatty acid profiles,protein content and w6/w3 ratio.

关键词： Insect farming chicken Local breed Growth performance Meat quality Fatty acid profile

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