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211.
Remote-sensing reflectance (R(rs)), which is defined as the ratio of water-leaving radiance (L(w)) to downwelling irradiance just above the surface (E(d)(0?)), varies with both water constituents (including bottom properties of optically-shallow waters) and angular geometry. L(w) is commonly measured in the field or by satellite sensors at convenient angles, while E(d)(0?) can be measured in the field or estimated based on atmospheric properties. To isolate the variations of R(rs) (or L(w)) resulting from a change of water constituents, the angular effects of R(rs) (or L(w)) need to be removed. This is also a necessity for the calibration and validation of satellite ocean color measurements. To reach this objective, for optically-deep waters where bottom contribution is negligible, we present a system centered on water's inherent optical properties (IOPs). It can be used to derive IOPs from angular Rrs and offers an alternative to the system centered on the concentration of chlorophyll. This system is applicable to oceanic and coastal waters as well as to multiband and hyperspectral sensors. This IOP-centered system is applied to both numerically simulated data and in situ measurements to test and evaluate its performance. The good results obtained suggest that the system can be applied to angular R(rs) to retrieve IOPs and to remove the angular variation of R(rs). 相似文献
212.
Eric Daniel Głowacki Gundula Voss Lucia Leonat Mihai Irimia-Vladu Siegfried Bauer Niyazi Serdar Sariciftci 《Israel journal of chemistry》2012,52(6):540-551
We describe the history of indigo dye and its derivative Tyrian purple, from their roles in the ancient world to recent research showing the semiconducting properties of indigoids. Indigoids are natural dyes that have been produced for centuries, and indigo is currently the most produced dye worldwide. Herein we review the history of these materials, their chemistry and physical properties, and their semiconducting characteristics in the solid state. Due to hydrogen bonding and π-stacking, indigo and Tyrian purple form highly-ordered crystalline thin films. Such films have been used to fabricate high-performance organic field-effect transistors with ambipolar charge transport, as well as complementary-like circuits. Mobility values were found to be in the range of 10−2–0.4 cm2/Vs. With performance on par with the best available organic semiconductors, indigoids demonstrate the potential of sustainable electronics based on biodegradable and biocompatible materials. 相似文献
213.
Wolfgang Brameshuber Univ.-Prof. Dr.-Ing. Rebecca Mott Dipl.-Ing. Josef Hegger Prof. Dr.-Ing. Stefan Voss Dipl.-Ing. Thomas Gries Prof. Dr.-Ing. Dipl.-Wirt. Ing. Marijan Barlé Dipl.-Ing. Stefan Böhm Prof. Dr.-Ing. Prof. h. c. Ilko Hartung Dipl.-Ing. 《Beton- und Stahlbetonbau》2008,103(2):64-72
Serial Batch Production of Building Members Made of Textile Reinforced Concrete Within a research project production techniques were investigated to produce building members made of textile reinforced concrete in a batch production. Laminating, casting, spraying and spinning techniques have been evaluated as well as a combination of these methods. In the beginning the main focus was the production and manufacturing technique with the adjustment of fine grained concrete and fabrics to the respective production technique and the development and choice of distance holders. In order to investigate the manufacturing technique specimens were comprehensively produced by means of selected production techniques. This contains the choice of an adequate production technique, the design of the selected building members, the production of the utilised fabrics as well as the production and testing of the building members. This procedure was carried out for the production of elements of an integrated formwork and spun concrete tubes. 相似文献
214.
Passive cooling of existing office buildings – proposal of a typology Passive cooling techniques use natural heat sinks (e. g. night air, ground) to dissipate excess heat while using storage effects in the building structure to modulate heat gains. Since most of the available heat sinks have a limited capacity a very low cooling load is a precondition. To assure a successful refurbishment of an office building with passive cooling techniques the question has to be discussed how suitable the buildings preconditions are. The paper discusses the building‐related and the non building‐related factors and establishes a typology. This typology allows identifying and classifying buildings according to their suitability for passive cooling. A “decision matrix” finally combines building‐related and non building‐related parameters and shows the buildings potential for passive cooling at an early stage of planning. 相似文献
215.
Gene therapy is one of the most rapidly evolving areas in medicine. Radiologists should have an understanding of basic techniques used to identify and clone a gene and insert it into a vector capable of directing expression in mammalian tissues. DNA delivery systems include retroviral vectors (RNA viruses), adenoviral vectors (DNA viruses), and cationic liposomes, along with strategies that involve ultrasound-directed gene transfer, computed tomography-guided gene transfer, and transcatheter gene delivery, in particular via the hepatic artery. Genes being evaluated in preclinical and clinical trials include oncogenes, antioncogenes (tumor suppressor genes), suicide genes, conventional antimetabolites, antiangiogenesis factors, secreted immunostimulatory cytokines such as interleukins and interferons, and immunomodulatory cell surface proteins, including foreign HLA proteins and costimulatory molecules. A foundation in molecular biology is needed for the practicing radiologist interested in but unfamiliar with current gene therapy terminology and experimental strategies. Such a foundation will encourage the dissemination of basic biologic, diagnostic imaging, and interventional oncoradiologic developments and should facilitate integration of the radiologist into the gene therapy team. 相似文献
216.
E Tolnay C Kuhnen T Wiethege JE K?nig B Voss KM Müller 《Canadian Metallurgical Quarterly》1998,124(6):291-296
The product of the p16/INK4a/CDKN2/MTS1 tumor-suppressor gene acts as a negative cell cycle regulator by inhibiting G1 cyclin-dependent kinases that phosphorylate the retinoblastoma protein. p16 is inactivated in a wide range of human malignancies, including familial melanoma. However, its expression and function in sporadic melanoma has not been extensively investigated. We studied p16 expression in 62 archival melanomas and 30 archival nevi and lentigines by immunohistochemistry. Eighteen of 26 (69%) superficial spreading melanomas, 17 of 28 (61%) nodular melanomas, all of three lentigo maligna melanomas, and all of five melanoma metastases were found to harbor less than 10% p16-positive tumor cells. In contrast, only six of 24 (25%) nevi had less than 10% positive cells. No correlation between tumor thickness and loss of p16 expression was found. Using DNA from micro-dissected tumor and matched normal tissues, five of seven (71%) p16-negative melanoma cases had 9p21 loss of heterozygosity (LOH), and one of these 9p21 LOH cases had promoter region hypermethylation of the remaining p16 allele. These data demonstrate that partial or complete loss of p16 expression is prevalent in sporadic melanoma and is frequently associated with 9p21 LOH. 相似文献
217.
S Jacobsen J Petersen S Ullman P Junker A Voss JM Rasmussen U Tarp LH Poulsen G van Overeem Hansen B Skaarup TM Hansen J P?denphant P Halberg 《Canadian Metallurgical Quarterly》1998,17(6):468-477
A Danish multicentre study was undertaken of the manifestations, infections, thrombotic events, survival and predictive factors of survival in 513 Danish patients with systemic lupus erythematosus (SLE) according to the 1982 classification criteria of the American College of Rheumatology. The mean duration of follow-up was 8.2 years from diagnosis and 12.8 years from first symptom. This paper describes the most common clinical and laboratory manifestations and their relationship to sex and age at the time of onset and diagnosis. Cluster analysis revealed three clinically defined clusters at the time of disease onset. Cluster 1 (57% of patients) consisted of relatively elderly patients without nephropathy or malar rash, but with a high prevalence of discoid lesions. Cluster 2 (18%) consisted of patients with nephropathy, a third of whom also developed serositis and lymphopenia. The patients of the third cluster (25%) all had malar rash and half were photosensitive. Follow-up showed that the patients of cluster 2 developed azotaemia, large proteinuria, arterial hypertension and myositis significantly more often than did the rest of the patients, but the mortality was not increased. The risk of developing renal end-stage disease was highest in men with early-onset disease. 相似文献
218.
FF Tu RL Goldenberg T Tamura M Drews SJ Zucker HF Voss 《Canadian Metallurgical Quarterly》1998,92(3):446-449
We investigated whether the src-family tyrosine kinase Lyn is involved in the generation of interferon alpha (IFN alpha) signals in haemopoietic cells. In vitro kinase assays using IFN alpha-sensitive cells of B-cell origin demonstrated the presence of IFN alpha-dependent kinase activity in anti-Lyn immunoprecipitates. Further studies demonstrated that Lyn associates via its src homology 2 (SH2) domain with the Janus family tyrosine kinase Tyk-2. This interaction was IFN alpha-dependent and involved direct binding of the SH2 domain of Lyn to the IFN alpha-activated form of Tyk-2. Thus, during binding of IFN alpha to its receptor in malignant haemopoietic cells, Lyn is engaged in an IFN alpha-signalling pathway, probably downstream of Tyk-2. 相似文献
219.