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Special Pattern (special + pattern)
Selected AbstractsInvolvement of Phytophthora species in white oak (Quercus alba) decline in southern OhioFOREST PATHOLOGY, Issue 5 2010Y. Balci Summary This study was initiated to investigate the possible role of Phytophthora species in white oak decline (Quercus alba) in southern Ohio at Scioto Trail State Forest. Surveys demonstrated the presence of four species of Phytophthora including one novel species. By far, the most common species was P. cinnamomi; P. citricola and P. cambivora were isolated infrequently. In few instances, P. cinnamomi was isolated from fine roots and necroses on larger roots. No special pattern of incidence was found, but P. cinnamomi was more commonly isolated from greater Integrated Moisture Index values suggesting moist lower bottomlands favour this Phytophthora species. When tree crown condition was examined relative to the presence of Phytophthora, no significant association was found. However, roots of declining P. cinnamomi -infested trees had 2.5 times less fine roots than non-infested and healthy trees, which was significantly different. The population densities of P. cinnamomi from declining trees were significantly greater than from healthy trees, suggesting increased pathogen activity that has the potential to cause dieback and decline and possibly the cause of a reduced fine root amount found on declining trees. [source] Frost formation on a bionic super-hydrophobic surface under natural convection conditionsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2008Yunjun Gou Abstract A bionic super-hydrophobic surface has a multiple micro-nano-binary structure (MNBS) similar to the lotus leaf surface microstructure. This kind of surface has a contact angle of water greater than 150° and a roll angle smaller than 5°. In this paper, the frost deposition phenomena on a bionic super-hydrophobic surface were observed. The surface has many micro bumps and its contact angle is 162°. The formation of water droplets, the droplet freezing process, the formation of initial frost crystals and the frost layer structure on a cold bionic super-hydrophobic surface under natural convection conditions were closely observed. The frost layer structure formed on the super-hydrophobic surface shows remarkable differences to that on a plain copper surface: the structure is weaker, looser, thin, and easily removed and most importantly, it is of a very special pattern, a pattern similar to a chrysanthemum, a frost layer structure that has not been reported before to the best of the present authors knowledge. The experimental results also show that a super-hydrophobic surface has a strong ability to restrain frost growth. The frost deposition on this bionic surface was delayed 55 minutes when compared with a plain copper surface under the conditions of a cold plate temperature of ,10.1°C, air temperature of 18.4°C, and relative humidity of 40%. A theoretical analysis was also presented to explain the observed phenomena. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(7): 412,420, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20216 [source] Cutaneous melanoma in Swedish women: Occupational risks by anatomic site,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2005Beatriz Pérez-Gómez MD Abstract Background Few occupational studies have addressed melanoma in women. Accordingly, our aim was to identify occupations with higher risk of cutaneous melanoma, overall and by site, in Swedish female workers. Methods All gainfully employed Swedish women were followed-up from 1971 to 1989, using Death/Cancer Registers. Occupational risk ratios adjusted for age, period, town size, and geographic zone were computed for each site. Risk patterns for different sites were then compared. Results High risks were observed among educators, bank tellers, dental nurses, librarians/archivists/curators, horticultural workers, and hatmakers/milliners. Telephone operators and textile workers had increased risk, mainly in the leg. Other occupation-specific site excesses were also found. Upper-limb risks were correlated with head/neck and thorax, though these two sites were not associated. Legs registered a special pattern, with a moderate correlation with upper limbs or thorax, and no correlation with head/neck. Conclusions Some occupations with possible exposure to arsenic/mercury displayed increased risk. The generalized excess risk among hatmakers/milliners warrants further attention. The weak correlation between legs and other sites suggests site specificity in melanoma risk factors. Am. J. Ind. Med. 2005. © 2005 Wiley-Liss, Inc. [source] Eigenvalues of factorable matrices with form IV symmetryINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 6 2005A. Kaveh Abstract The methods developed for eigensolution of matrices with special patterns (Commun. Numer. Methods Engng 2003; 19: 125; 2004; 20: 133) is extended to another canonical form defined as the symmetry of Form IV. Efficient methods are presented for evaluating the eigenvalues for this form of matrices. The graph representation of this type of symmetry is also included in this study. The process of development is accompanied by some illustrative examples. Copyright © 2005 John Wiley & Sons, Ltd. [source] Eigensolution of symmetric frames using graph factorizationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 12 2004A. Kaveh Abstract In this paper, decomposition of matrices of special patterns to submatrices of smaller dimensions is briefly described. The graph models of frame structures with different symmetries are decomposed and appropriate processes are designed for their healing in order to form the corresponding factors. The eigenvalues and eigenvectors of the entire structure are then obtained by evaluating those of its factors. The methods developed in this article, simplifies the calculation of the natural frequencies and natural modes of the planar frames with different types of symmetry. Copyright © 2004 John Wiley & Sons, Ltd. [source] Non-randomness in the species,area relationship: testing the underlying mechanismsOIKOS, Issue 4 2007Simone Fattorini The species,area relationship (SAR) is one of the best documented patterns in ecology. However, interrelations between the SAR and species distributions are largely unexplored. This research was aimed (1) to assess if the SAR for a group of sedentary insects is associated to a random or non-random distribution of species across islands in a land-bridge archipelago, and (2) to investigate possible factors responsible for the non-randomness. Communities of tenebrionid beetles on the Aegean Islands (Greece) were studied as a case of a relict fauna. Three aspects of non-randomness were analysed: (1) non-random variation of species richness in the SAR, (2) degree of nestedness and (3) presence of special patterns of co-occurrence. Species co-occurrence and nestedness analyses indicated that historical aspects, as opposed to interspecific competition or distance-mediated colonization events, have moulded these species distributions. [source] | |||||||||||||