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Facial Skin Rejuvenation with High Frequency Ultrasound: Multicentre Study of Dual-Frequency Ultrasound

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Journal of Cosmetics, Dermatological Sciences and Applications 2012年第2期2卷 68-73页

作者： dirk meyer-Rogge Frank Rosken Peter Holzschuh Bruno D’hont Ilja Kruglikov Derma-Clinic KarlsruheGermany Die Astheten MunichGermany Optima Clinic KarlsruheGermany Skinline Clinic Sint-Pieters-LeeuwBelgium Wellcomet GmbH KarlsruheGermany

According to modern theories, the process of skin ageing may be connected with local up-regulation of matrix metalloproteinases (MMP) and down-regulation of heat shock proteins (HSP) in the skin. In this pragmatic, non-randomised, multicentre study we investigated the skin rejuvenation effect of dual-frequency ultrasound, with frequencies of 3 and 10 MHz, which has the ability to modulate both MMPs and HSPs. It was shown that such waves can significantly improve different visual appearances of ageing skin. This safe, non-invasive method yields results that are not as marked as those shown by injecting of fillers, but can be successfully used by subjects with a broad spectrum of visual skin ageing problems, which have to be treated simultaneously.

关键词： Skin Rejuvenation Dual-Frequency Ultrasound Matrix Metalloproteinases Heat Shock Proteins

Extreme biomimetic approach for developing novel chitin-GeO2 nanocomposites with photoluminescent properties

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Nano Research 2015年第7期8卷 2288-2301页

作者： Marcin Wysokowski Mykhailo Motylenko Jan Beyer Anna Makarova Hartmut Stocker Juliane Walter Roberta Galli Sabine Kaiser Denis Vyalikh Vasilii V. Bazhenov laroslav Petrenko Allison L Stelling Serguei L. Molodtsovs Dawid Stawski Krzysztof J.Kurzydfowski Enrico Langer Mikhail V Tsurkan Teofil Jesionowski Johannes Heitmann dirk C. meyer Hermann Ehrlich Institute of Chemical Technology and Engineering Poznan University of Technology 60965 Poznan Poland Institute of Materials Science TU Bergakademie Freiberg 09599 Freiberg Germany Institute of Applied Physics TU Bergakademie Freiberg 09599 Freiberg Germany Institute of Solid State Physics Dresden University of Technology 01069 Dresden Germany Institute of Experimental Physics TU Bergakademie Freiberg 09599 Freiberg Germany Faculty of Medicine Carl Gustav Carus Department of Anaesthesiology and Intensive Care Medicine Clinical Sensoring and Monitoring TU Dresden 01069 Dresden Germany epartment of Physics St. Petersburg State University 198504 St. Petersburg Russia Department of Mechanical Engineering and Materials Science Duke University 27708 Durham NC USA European X-Ray Free-Electron Laser Facility (XFEL) GmbH 22761 Hamburg Germany ITMO University 197101 St. Petersburg Russia Department of Commodity and Material Sciences and Textile Metrology Technical University of Lodz 90924 LSdz Poland Materials Design Group Faculty of Materials Science and Engineering Warsaw University of Technology PL-02507 Warsaw Poland Institute of Semiconductors and Microsystems TU Dresden 01062 Dresden Germany Leibniz Institute of Polymer Research Max Bergmann Centre for Biomaterials 01062 Dresden Germany

This work presents an extreme biomimetics route for the creation of nano- structured biocomposites utilizing a chitinous template of poriferan origin. The specific thermal stability of the nanostructured chitinous template allowed for the formation under hydrothermal conditions of a novel germanium oxide- chitin composite with a defined nanoscale structure. Using a variety of analytical techniques （FTIR, Raman, energy dispersive X-ray （EDX）, near-edge X-ray absorption fine structure （NEXAFS）, and photoluminescence （PL） spectroscopy, EDS-mapping, selected area for the electron diffraction pattern （SAEDP）, and transmission electron microscopy （TEM））, we showed that this bioorganic scaffold induces the growth of GeO2 nanocrystals with a narrow （150-300 nm） size distri- bution and predominantly hexagonal phase, demonstrating the chitin template＇s control over the crystal morphology. The formed GeO2-chitin composite showed several specific physical properties, such as a striking enhancement in photo- luminescence exceeding values previously reported in GeOR-based biomaterials. These data demonstrate the potential of extreme biomimetics for developing new-generation nanostructured materials.

关键词： extreme biomimetics, chitin-GeO2 photoluminescence, near-edge X-ray absorption fine structure (NEXAFS) spectroscopy

Mitogenomic phylogeny of the Asian colobine genus Trachypithecus with special focus on Trachypithecus phayrei(Blyth, 1847) and description of a new species

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Zoological Research 2020年第6期41卷 656-669页

作者： Christian Roos Kristofer MHelgen Roberto Portela Miguez Naw May Lay Thant Ngwe Lwin Aung Ko Lin Aung Lin Khin Mar Yi Paing Soe Zin Mar Hein Margaret Nyein Nyein Myint Tanvir Ahmed Dilip Chetry Melina Urh EGrace Veatch Neil Duncan Pepijn Kamminga Marcus AHChua Lu Yao Christian Matauschek dirk meyer Zhi-Jin Liu Ming Li Tilo Nadler Peng-Fei Fan Le Khac Quyet Michael Hofreiter Dietmar Zinner Frank Momberg Primate Genetics Laboratory German Primate CenterLeibniz Institute for Primate ResearchGoettingen 37077Germany Gene Bank of Primates German Primate CenterLeibniz Institute for Primate ResearchGoettingen 37077Germany Chances for Nature(CfN) Goettingen 37073Germany Australian Museum Research Institute Australian MuseumSydneyNew South Wales 2010Australia Natural History Museum London SW7 BDUK Wildlife Conservation Society(WCS)-Myanmar Program Yangon 11041Myanmar Fauna&Flora International(FFI)-Myanmar Programme Yangon 11201Myanmar Popa Mountain Park Nature and Wildlife Conservation DivisionForest DepartmentPopa 05242Myanmar World Wide Fund for Nature(WWF)-Myanmar Yangon 11191Myanmar Department of Zoology Jagannath UniversityDhaka 1100Bangladesh Primate Research and Conservation Division AaranyakGuwahatiAssam 781028India Department of Anthropology Emory UniversityAtlantaGA 30322USA Department of Anthropology Yale UniversityNew HavenCT 06511USA Department of Mammalogy American Museum of Natural HistoryNew YorkNY 10024USA Naturalis Biodiversity Center Leiden 2333 CRThe Netherlands Lee Kong Chian Natural History Museum National University of SingaporeSingapore 117377Singapore Department of Environmental Science and Policy George Mason UniversityFairfaxVA 22030USA Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China Cuc Phuong Commune Nho Quan DistrictNinh Binh ProvinceVietnam School of Life Sciences Sun Yat-Sen UniversityGuangzhouGuangdong 510275China Center for Biodiversity Conservation and Endangered Species Ho-Chi-Minh CityVietnam Institute for Biochemistry and Biology University of PotsdamPotsdam 14476Germany Cognitive Ethology Laboratory German Primate CenterLeibniz Institute for Primate ResearchGoettingen 37077Germany Leibniz Science Campus Primate Cognition Goettingen 37077Germany De

Trachypithecus,which currently contains 20 species divided into four groups,is the most speciose and geographically dispersed genus among Asian *** several morphological and molecular studies,however,its evolutionary history and phylogeography remain poorly ***’s langur(Trachypithecus phayrei) is one of the most widespread members of the genus,but details on its actual distribution and intraspecific taxonomy are limited and ***,to elucidate the evolutionary history of Trachypithecus and to clarify the intraspecific taxonomy and distribution of ***,we sequenced 41 mitochondrial genomes from georeferenced fecal samples and museum specimens,including two *** analyses revealed a robustly supported phylogeny of Trachypithecus,suggesting that the *** group branched first,followed by the *** group,and the *** and *** groups most *** four species groups diverged from each other 4.5-3.1 million years ago(Ma),while speciation events within these groups occurred much more recently(1.6-0.3 Ma).Within ***,we found three clades that diverged 1.0-0.9 Ma,indicating the existence of three rather than two *** the phylogenetic species concept and based on genetic,morphological,and ecological differences,we elevate the *** subspecies to species level,describe a new species from central Myanmar,and refine the distribution of the three ***,our study highlights the importance of museum specimens and provides new insights not only into the evolutionary history of *** but the entire Trachypithecus genus as well.

关键词： Colobinae Integrative zoology Mitochondrial genome Museum specimens New species

Multi-scale simulations of apatite-collagen composites： from molecules to materials

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Frontiers of Materials Science 2017年第1期11卷 1-12页

作者： dirk ZAHN Lehrstuhl for Theoretische Chemie/Computer Chemie Centrum Friedrich-Alexander Universitat Erlangen-Numberg Nagelsbachstraβe25 91052 Erlangen Germany

We review scale-bridging simulation studies for the exploration of atomic- to-meso scale processes that account for the unique structure and mechanic properties of apatite-protein composites. As the atomic structure and composition of such complex biocomposites only partially is known, the first part （i） of our modelling studies is dedicated to realistic crystal nucleation scenarios of inorganic-organic composites. Starting from the association of single ions, recent insights range from the mechanisms of motif formation, ripening reactions and the self-organization of nanocrystals, including their interplay with growth-controlling molecular moieties. On this basis, （ii） reliable building rules for unprejudiced scale-up models can be derived to model bulk materials. This is exemplified for （enamel-like） apatite-protein composites, encompassing up to 106 atom models to provide a realistic account of the 10 nm length scale, whilst model coarsening is used to reach pm length scales. On this basis, a series of deformation and fracture simulation studies were performed and helped to rationalize biocomposite hardness, plasticity, toughness, self-healing and fracture mechanisms. Complementing experimental work, these modelling studies provide particularly detailed insights into the relation of hierarchical composite structure and favorable mechanical properties.

关键词： biocomposites deformation fracture molecular simulation

Structural pavement assessment in Germany

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 183-191页

作者： Lutz PINKOFSKY dirk JANSEN Bundesanstalt fur Straflenwesen (Federal Highway Research Institute) BASt Bruederstrasse 53 51427 Bergisch Gladbach Germany

The aging structure as well as the considerable increase of heavy-traffic load on Germany＇s motorways and trunk roads encourages the use of innovative, sound and reliable methods for the structural assessment on network level as well as on project level. Essential elements for this are data, which allow a reliable assessment. For a holistic approach to structural pavement assessment performance orientated measurements will be necessary. In combination with functional parameters as well as write-down models, strategically motivated decision making processes will be useful combined with technically motivated decision processes. For the application at the network level, the available methods for performance orientated measurements are still challenging, as they are based either on testing drill-cores or on non- traffic speed methods. In recent years significant innovation steps have been made to bring traffic speed bearing capacity measurements and methods for evaluating pavement structures on the road. The paper summarizes the actual assessment procedures in Germany as well as the ongoing work on the development and implementation of new methods and techniques.

关键词： pavement assessment Germany structure system

The role of phosphorus in the metabolism of arsenate by a freshwater green alga, Chlorella vulgaris

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Journal of Environmental Sciences 2016年第11期28卷 169-178页

作者： Josh Baker dirk Wallschlager Trent University Environmental and Life Sciences Graduate Program 1600 West Bank Dr Peterborough ON K9L 0G2 Canada School of the Environment Department of Chemistry and Water Quality Centre Trent University 1600 West Bank Dr Peterborough ONK9L 0G2 Canada

A freshwater microalga, Chlorella vulgaris, was grown in the presence of varying phosphate concentrations（〈 10–500 μg/L P） and environmentally realistic concentrations of arsenate（As（Ⅴ））（5–50 μg/L As）. Arsenic speciation in the culture medium and total cellular arsenic were measured using AEC-ICP-MS and ICP-DRC-MS, respectively, to determine arsenic biotransformation and uptake in the various phosphorus scenarios. At high phosphate concentration in the culture medium, 〉 100 μg/L P, the uptake and biotransformation of As（Ⅴ） was minimal and dimethylarsonate（DMAs（Ⅴ）） was the dominant metabolite excreted by C. vulgaris, albeit at relatively low concentrations. At common environmental P concentrations, 0–50 μg/L P, the uptake and biotransformation of As（Ⅴ） increased. At these higher As-uptake levels, arsenite（As（Ⅲ）） was the predominant metabolite excreted from the cell. The concentrations of As（Ⅲ） in these low P conditions were much higher than the concentrations of methylated arsenicals observed at the various P concentrations studied. The switchover threshold between the（small） methylation and（large） reduction of As（Ⅴ） occurred around a cellular As concentration of 1 fg/cell. The observed nearly quantitative conversion of As（Ⅴ） to As（Ⅲ） under low phosphate conditions indicates the importance of As（Ⅴ） bio-reduction at common freshwater P concentrations. These findings on the influence of phosphorus on arsenic uptake, accumulation and excretion are discussed in relation to previously published research. The impact that the two scenarios of As（Ⅴ） metabolism, As（Ⅲ） excretion at high As（Ⅴ）-uptake and methylarsenical excretion at low As（Ⅴ）-uptake, have on freshwater arsenic speciation is discussed.

关键词： Arsenic Speciation Phosphorus Freshwater algae Toxicity Biotransformation

Numerical modelling of a turbulent bluff-body flow with Reynolds stress turbulent models

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Progress in Natural Science:Materials International 2005年第5期15卷 458-462页

作者： dirk ROEKAERTS CJ2628 Delft Delft University of Technology Department of Applied Physics The Netherlands

Numerical modelling of a turbulent bluff-body flow has been performed using differential Reynolds stress models (DRSMs). To clarify the applicability of the existing DRSMs in this complex flow, several typical DRSMs, including LRR-IP model, JM model, SSG model, as well as a modified LRR-IP model, have been validated and evaluated. The performance difference between various DRSMs is quite significant. Most of the above mentioned DRSMs cannot provide overall satisfactory predictions for this challenging test case. Motivated by the deficiency of the existing approaches, a new modification of LRR-IP model has been proposed. A very significant improvement of the prediction of flow field is obtained.

关键词： bluff-body flow differential Reynolds stress models turbulent model.

Phosphorus release from vivianite and hydroxyapatite by organic and inorganic compounds

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Pedosphere 2020年第2期30卷 190-200页

作者： Stella GYPSER dirk FREESE Brandenburg University of Technology Cottbus-Senftenberg Faculty of EnvironmentProcess EngineeringBiotechnology and ChemistryDepartment of Soil Protection and RecultivationKonrad-Wachsmann-Allee 6Cottbus 03046Germany

Based on recent mining rates and the exhaustion of global phosphorus(P)reserves,there is a need to mobilize P already stored in soils,and its recovery from secondary resources such as Ca-and Fe-phosphates is *** Ca-phosphate hydroxyapatite forms a good fertilizer source,while vivianite is formed in waterlogged soils and *** sludge treatment,the formation of vivianite has been identified,being mainly ***-term P release from both hydroxyapatite and vivianite was studied using different inorganic(CaCl2 and CaSO4)and organic(citric and humic acid)reagents during batch *** CaCl2 and CaSO4 represent the soil solution,while citric and humic acids as organic constituents affect P availability in the rhizosphere and during the process of ***,the flow-through reactor(FTR)technique with an infinite sink was used to study the long-term P release *** cumulative P release was higher by organic acids than by inorganic *** cumulative P release rates were higher in the FTR with CaCl2 as compared to the batch *** infinite sink application caused a continuously high concentration gradient between the solid and liquid phases,leading to higher desorption rates as compared to the batch *** predominant amount of the total P released over time was available for a short *** inorganic anion exchange occurred at easily available binding sites,organic acids affected the more heavily available binding sites,which could be embedded within the mineral *** results showed that organic compounds,especially citric acid,play a superior role as compared to the inorganic constituents of the soil solution during the recovery of already stored P from the tertiary phosphates vivianite and hydroxyapatite.

关键词： anion exchange batch technique citric acid flow-through reactor humic acid ligand exchange phosphate phosphorus recovery

Utilization of fly ash from coal-fired power plants in China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 681-687页

作者： Eva SELIC Jan-dirk HERBELL Waste Management Engineering Department of Mechanical Engineering University of Duisburg-Essen Duisburg 47057 Germany

The rapidly increasing demand for energy in China leads to the construction of new power plants all over the country. Coal, as the main fuel resource of those power plants, results in increasing problems with the disposal of solid residues from combustion and off gas cleaning. This investigation describes chances for the utilization of fly ash from coal-fired power plants in China. After briefly comparing the situation in China and Germany, the status of aluminum recycling from fly ash and the ad- vantages for using fly ash in concrete products are introduced. Chemical and physical analyses of Chinese fly ash samples, e.g., X-ray diffraction (XRD), ICP (Inductive Coupled Plasma) and particle size analysis, water requirement, etc. are presented. Rea- sonable amounts of aluminum were detected in the samples under investigation, but for recovery only sophisticated procedures are available up to now. Therefore, simpler techniques are suggested for the first steps in the utilization of Chinese fly ash.

关键词： Fly ash utilization Aluminum recycling Concrete Chemical and physical analyses