Evaluation of the photo stabilising efficiency of clear coatings comprising organic UV absorbers and mineral UV screeners on wood surfaces     

Boris Forsthuber  Christian Schaller  Gerhard Grüll 《Wood Science and Technology》2013,47(2):281-297

A study of the surface discolouration of clear coated wood during artificial and outdoor weathering and its prevention using clear coatings comprising organic UV absorbers (UVA) and mineral UV screeners was carried out. It was shown that the use of UVA and UV screeners in clear coatings was very effective in reducing photodegradation of the wood surface. Preliminary irradiation trials with Xenon arc light showed that the UV screener TiO₂ led to the least discolouration of the coated wood surface, closely followed by UVA of the hydroxyphenyl-s-triazine class (HPT). The artificial and outdoor weathering trials indicated that UVA of the HPT class stabilised the colour of the wood surface better than UVA of the 2-(2-hydroxyphenyl)-benzotriazole class (BTZ). Comparison of different artificial weathering methods indicated that Xenon arc light weathering showed the best match to the proceeding discolouration of the clear coated wood panels during outdoor weathering.  相似文献   

Response of Potato (Solanum tuberosum L.) Germplasm to Water Stress Under In Vitro Conditions     

Macarena Barra  José Correa  Erika Salazar  Boris Sagredo 《American Journal of Potato Research》2013,90(6):591-606

Chile is center of origin and diversity of potato (Solanum tuberosum L.). Potato yield is affected under water stress conditions, so development of varieties with better tolerance to this stress is desirable. In this study we determined the differential response of INIA-Chile potato germplasm to water stress under in vitro assays with polyethylene glycol. One-hundred-and-fourty-nine genotypes were evaluated. Polyethylene glycol 4.8 % w/v was able to distinguish genotype response by considering the morphological variables (plantlet height, leaf and root number) and fresh and dry weight. Through multivariate statistical analysis, and in comparison with their respective controls without treatment, genotypes were clustered with high (74 – 79 %), intermediate (29 – 94 %), low (29 – 57 %), and very low (4– 28 %) water stress tolerance. The high-tolerance-response cluster was mainly made up of Chilean potato landraces. These results highlight the importance of this germplasm in food security, which could be directly cultivated and/or be used as progenitors to produce new varieties with increased tolerance to water-deficit stress.  相似文献   

Silver containing sol-gel coatings on polyamide fabrics as antimicrobial finish-description of a technical application process for wash permanent antimicrobial effect     

Boris Mahltig  Torsten Textor 《Fibers and Polymers》2010,11(8):1152-1158

This paper reports on an antimicrobial finishing for polyamide with high washfastness. As antimicrobial agent modified silica sols containing silver components are used as coating agent and are applied to the polyamide fabric by using a semi-industrial procedure. The antimicrobial properties of coated polyamide fabrics are determined against the bacteria E. coli. Significant antimicrobial effects are observed even after 40 washing cycles. The amount of silver on the polyamide fabrics was measured by using ICP-OES. Besides this, samples are investigated by means of UV/Vis-spectroscopy and scanning electron microscopy. Furthermore textile properties as, e.g., air permeability and mechanical properties were measured. Due to high antimicrobial effect and the strong washfastness of this finishing, this reported method could be of high interest for industrial production processes.  相似文献   

Challenges of species distribution modeling belowground     

Boris Schröder 《植物养料与土壤学杂志》2008,171(3):325-337

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Evaluating CENTURY and Yasso soil carbon models for CO2 emissions and organic carbon stocks of boreal forest soil with Bayesian multi‐model inference     

Boris &#x;upek  Samuli Launiainen  Mikko Peltoniemi  Risto Sievnen  Jari Perttunen  Liisa Kulmala  Timo Penttil  Antti‐Jussi Lindroos  Shoji Hashimoto  Aleksi Lehtonen 《European Journal of Soil Science》2019,70(4):847-858

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Prevention and treatment of respiratory diseases in young cattle     

J Espinasse 《DTW. Deutsche tier?rztliche Wochenschrift》1987,94(5):240-247

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A new diarrhoeic syndrome with ataxia in young Charolais calves: clinical and microbiological studies.   总被引：1，自引：0，他引：1  

J Espinasse  H Navetat  M Contrepois  D Baroux  F Schelcher 《The Veterinary record》1991,128(18):422-425

A new diarrhoeic syndrome was examined clinically in 19 one to two-week old Charolais calves. It differs from other digestive disorders in calves of this age in the discrete diarrhoeic signs, the absence of dehydration and the presence of signs of ataxia. The microbiological study carried out for three consecutive years in 58 sick calves and nine healthy control calves demonstrated the special role of E coli possessing virulence markers from septicaemic strains (CS31A, Col V). The clinical signs could be the result of bacteraemia with subacute E coli endotoxaemia.  相似文献   

How much space does a seedling need?     

Boris Zeide 《Forest Ecology and Management》1985,11(3):225-229

A method is described to identify canopy trees which significantly affect regeneration at a given point, estimate the effect of these trees on the growth and survival of seedlings, and determine the maximum density of the canopy trees compatible with successful regeneration. All this information is obtained using point sampling done with several basal area factors from the same point. An example of the method's application is provided.  相似文献   

Ultrastructure of Archigetes sieboldi (Cestoda: Caryophyllidea): relationship between progenesis, development and evolution     

Poddubnaya LG  Mackiewicz JS  Kuperman BI 《Folia parasitologica》2003,50(4):275-292

Ultrastructural characteristics of progenetic and monoxenic Archigetes sieboldi Leuckart, 1878 from the oligochaete Limnodrilus hoffmeisteri Claparède are described. Our observations demonstrate that progenetic Archigetes sieboldi shares characteristics of both larval (progenetic) and adult stages. The primary larval characteristics are: the presence of a cercomer; a surface filamentous coat covering the whole worm; the presence of the penetration glands and the absence of tegumental ones; wide sarcoplasmic processes connecting the circular and longitudinal external tegumental muscles; the absence of the dense homogenous zone of the basal lamina beneath the epithelial cytoplasm of all reproductive organs and ducts; non-functional gonopores; and an orthogonal plan of nervous system with three pairs of longitudinal nerve trunks. The principle adult characteristics are: oogenesis, spermiogenesis and vitellogenesis that produce fertilized eggs; the uterine glands; a well-developed longitudinal tegumental muscle layer between tegumental cytons; and the presence of different microtriches. As a result of this progenetic development there has been a secondary reduction in the life cycle of A. sieboldi. It is postulated that a similar process of progenesis may have played a major role in the early evolution of the Caryophyllidea by first appearing in a plerocercoid stage of an ancestral strobilate cestode from fish.  相似文献   

Latitudinal gradients in body size and sexual size dimorphism in fleas: males drive Bergmann's pattern     

Boris R. KRASNOV  Elena N. SURKOVA  Georgy I. SHENBROT  Irina S. KHOKHLOVA 《Integrative zoology》2023,18(3):414-426

We tested for the effects of latitude and geographic range size (GRS) on body size, leg length, and sexual size dimorphism (SSD) across 103 species of fleas, taking into account phylogenetic between-species relationships. When the data on body size were combined for males and females, the positive correlation between body size and latitude, but not GRS, was revealed. When the analysis was restricted to one sex only, the effect of latitude appeared to be non-significant for females, whereas male body size increased with an increase in latitude. Intraspecific body size variation was not associated with either the latitude or the latitudinal span of the geographic range, independently of which data subset was analyzed. No evidence of association between size-independent tibia length and latitude was found for either females, males, or both sexes combined. The degree of SSD decreased with a decrease in latitude but was not affected by GRS. We conclude that macroecological patterns might be manifested differently in males and females. This should be kept in mind while searching for these patterns.  相似文献