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921.
Pepper G. Glass 《Ethnic and racial studies》2017,40(14):2520-2538
While researchers frequently link the construction of racial meanings with the construction of spatial meanings, studies of race have paid little attention to how other forms of space making affect racial divisions. This study, based on interviews collected while residents of Ogden, Utah travelled around their city, explores how collective attachments to place intersect with racialized divisions of it. Residents saw their community as divided into good (white) and bad (people of colour) areas. Yet, they also united as residents to defend the city against negative assessments. These multiple and shifting understandings, simultaneously dividing and uniting the city, suggest that other forms of spatial meaning making can challenge racialized definitions of space. 相似文献
922.
The amino terminus of bovine rhodopsin is blocked and has the sequence x-Met-Asn(CHO)-Gly-Thr-Glu-Gly-Pro-Asn-Phe-Tyr-Val-Pro-Phe-Ser-Asn(CHO)-Lys-Thr-Gly-Val-Val-Arg, where CHO represents sites of carbohydrate attachment. The carboxyl-terminal sequence of rhodopsin is Val-Ser-Lys-Thr-Glu-Thr-Ser-Gln-Val-Ala-Pro-Ala. Upon short-term digestion of rod outer segment (ROS) membranes with thermolysin, opsin (~ 35,000 daltons) is converted to a membrane-bound fragment O′ (~ 30,500 daltons) and 2 peptides containing 12 amino acids are released from the carboxyl terminus of rhodopsin into the supernatant. Upon long-term digestion of ROS with thermolysin, opsin and O′ are replaced by the membrane-bound fragments F1 (~25,000 daltons), and F2 (~9,500 daltons). When 32P-ROS are digested, F2 carries the 32P. Both O′ and F1 contain the amino-terminal glycopeptide. 相似文献
923.
Dr. Benita Plesch 《Cell and tissue research》1976,171(3):389-396
The attachment of the body of the snail Lymnaea stagnalis to the shell was studied by histochemistry and light and electron microscopy. Muscles of the body wall insert into the connective tissue by way of long thin projections of sarcolemma. The muscle cells end under the basement membrane of a specialised area of the epidermis, the adhesive epithelium. The cells of this epithelium are filled with microfilaments and possess characteristic knob-like microvilli. The epithelium is attached to the shell by way of an adhesive substance containing proteins and mucopolysaccharides.This research was made possible by a grant from the Netherlands Organization for Pure Research (Z.W.O.) 相似文献
924.
Cellular functions are always performed by protein complexes. At present, many approaches have been proposed to identify protein complexes from protein–protein interaction (PPI) networks. Some approaches focus on detecting local dense subgraphs in PPI networks which are regarded as protein‐complex cores, then identify protein complexes by including local neighbors. However, from gene expression profiles at different time points or tissues it is known that proteins are dynamic. Therefore, identifying dynamic protein complexes should become very important and meaningful. In this study, a novel core‐attachment–based method named CO‐DPC to detect dynamic protein complexes is presented. First, CO‐DPC selects active proteins according to gene expression profiles and the 3‐sigma principle, and constructs dynamic PPI networks based on the co‐expression principle and PPI networks. Second, CO‐DPC detects local dense subgraphs as the cores of protein complexes and then attach close neighbors of these cores to form protein complexes. In order to evaluate the method, the method and the existing algorithms are applied to yeast PPI networks. The experimental results show that CO‐DPC performs much better than the existing methods. In addition, the identified dynamic protein complexes can match very well and thus become more meaningful for future biological study. 相似文献
925.
Hayden A Homer 《Cell cycle (Georgetown, Tex.)》2014,13(8):1222-1223
926.
927.
《Cell Stem Cell》2021,28(9):1625-1640.e6
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928.
The pretarsal arolium serves as an attachment device in many groups of insects, enabling them to walk efficiently on smooth surfaces, where claws alone do not provide sufficient foothold. The arolia of representatives of all major lineages of Auchenorrhyncha are described and illustrated, mainly using scanning electron microscopy and histology. Glands inside the lumen of the arolia are described for the first time in this group. It is shown that the morphology of arolia within Auchenorrhyncha differs considerably. Some of them are even distinctly bilobed. The cuticle of the contact zone is thickened and formed of branching chitinous rods. In some cases, two layers of rods oriented in different directions were found. An extended definition of “arolium” is proposed. J. Morphol. 275:1217–1225, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
929.
《Anthrozo?s》2013,26(3):249-261
ABSTRACTA 35-item questionnaire (DAQ: Dog Attachment Questionnaire) involving 5-point Likert responses to items designed to measure aspects of attachment to a pet/companion animal dog was constructed. The content was derived from theoretical treatments of adult human attachment, used in a broad sense as equivalent to an affectional bond. Items based on four groupings were modified for a pet dog. Two samples of dog owners (n = 112 and 306, respectively) were used to investigate the factor structure of the questionnaire, using first exploratory and then confirmatory factor analysis (CFA). The questionnaire showed high overall internal consistency, it indicated a high level of attachment to the pets, and factor analysis indicated a four-factor solution, which was replicated using CFA in Sample 2. Three of these factors produced reliable subscales, indicating (1) degree of closeness with the pet; (2) caring and protecting the pet, and companionship; (3) as a secure base and a source of emotional comfort and well-being. In sample 2, Total DAQ scores were positively related to a single-item pictorial measure of attachment to the dog, and were higher for women than men but not associated with age or duration of ownership. 相似文献
930.
This work reports on a simple, robust and scientifically sound method to develop surfaces able to reduce microbial attachment and biofilm development, with possible applications in medicine, dentistry, food processing, or water treatment. Anodic surfaces with cylindrical nanopores 15 to 100 nm in diameter were manufactured and incubated with Escherichia coli ATCC 25922 and Listeria innocua. Surfaces with 15 and 25 nm pore diameters significantly repressed attachment and biofilm formation. Surface–bacteria interaction forces calculated using the extended Derjaguin Landau Verwey-Overbeek (XDLVO) theory indicate that reduction in attachment and biofilm formation is due to a synergy between electrostatic repulsion and surface effective free energy. An attachment study using E. coli K12 strains unable to express appendages also suggests that the small-pore surfaces may inhibit flagella-dependent attachment. These results can have immediate, far-reaching implications and commercial applications, with substantial benefits for human health and life. 相似文献