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101.
An attempt is made to provide a tool for systematically analyzing variations of outdoor human energy budgets and skin temperatures as a result of different urban street canyon geometries and vegetative properties. To this end, three previously developed numerical models were combined. The interaction of the models and the derivation of the necessary human-urban view-factors is discussed. Some sample results are given for non-urban macadam and park plains, to be used later as standards in the comparison of the impact of urban morphology on human comfort.  相似文献   
102.
103.
Summary The method of estimating interactions proposed independently by Pimm and Schoener is studied using field data from the community of rodents which lives in the arid, rocky habitats of Israel. One important problem the method addresses is how to remove the effects of habitat heterogeneity on the estimate. We tried six different variations of the analysis scheme outlined by Crowell and Pimm, and found their results qualitatively inconsistent. This was especially true when we compared the results produced from separate habitat variables with those produced from the principal components of the habitat variation.Another problem, this one not previously addressed, is great variation in the average abundance of the different species. We discovered that the ratio of the average abundances of two species is the best predictor of the value of their coefficients of interaction. Common species appear to have weak influence on rare ones; rare ones appear to have strong influence on common ones. The statistical mechanism which produces this relationship is clear, indicating that the relationship is an artifact.  相似文献   
104.
Obesity and type 2 diabetes are associated with increased production of Galectin-3 (Gal-3), a protein that modulates inflammation and clearance of glucose adducts. We used Lean and Diet-induced Obese (DIO) WT and Gal-3 KO mice to investigate the role of Gal-3 in modulation of adiposity, glucose metabolism and inflammation. Deficiency of Gal-3 lead to age-dependent development of excess adiposity and systemic inflammation, as indicated by elevated production of acute-phase proteins, number of circulating pro-inflammatory Ly6Chigh monocytes and development of neutrophilia, microcytic anemia and thrombocytosis in 20-week-old Lean and DIO male Gal-3 KO mice. This was associated with impaired fasting glucose, heightened response to a glucose tolerance test and reduced adipose tissue expression of adiponectin, Gal-12, ATGL and PPARγ, in the presence of maintained insulin sensitivity and hepatic expression of gluconeogenic enzymes in 20-week-old Gal-3 KO mice compared to their diet-matched WT controls. Expression of PGC-1α and FGF-21 in the liver of Lean Gal-3 KO mice was comparable to that observed in DIO animals. Impaired fasting glucose and altered responsiveness to a glucose load preceded development of excess adiposity and systemic inflammation, as demonstrated in 12-week-old Gal-3 KO mice. Finally, a role for the microflora in mediating the fasting hyperglycemia, but not the excessive response to a glucose load, of 12-week-old Gal-3 KO mice was demonstrated by administration of antibiotics. In conclusion, Gal-3 is an important modulator of glucose metabolism, adiposity and inflammation.  相似文献   
105.
Reviews     
The Family Album. A film by Alan Berliner. 16mm, 55min, b/w. Distributed by Filmmakers Library, Inc.

Beyond Words—Images from America's Concentration Camps. By Deborah Gesensway and Mindy Roseman. 1987, 176 pages, illustrated. Ithaca: Cornell University Press. Price: cloth $24.95.

The Lau (Granada Television “Disappearing World” Series). A film by Leslie Woodhead, producer‐director; Jon Woods, camera; Ray French, sound; Kimball Horton, editor; David Wasson, researcher; and Pierre Maranda, anthropological consultant. 1987, video, color, 52 minutes. Dialogues: Lau. Subtitles: English. Narration: English. Distributed by Granada TV International, Suite 3468, 1221 Avenue of the Americas, New York, NY 10020, tele. 212–242–2363. Price: on application.

Men's Lives: The Surfmen and Baymen of the South Fork. By Peter Matthiessen. 1986, New York: Random House. Price: hardcover $29.95; softcover $7.95 (Vintage Press); limited edition $200 (University of Washington Press, Seattle).

In Her Own Time. A film by Lynne Littman with Barbara Myerhoff. 1986, 16mm, color, 60 minutes. Distributed by Direct Cinema, Ltd., P.O. Box 69589, Los Angeles, CA 90060, tele. 213–652–8000. Price: 16mm—purchase $895, rental $100; video—purchase $350, rental $50 (prices quoted are for educational institutions only).

The Miracle of Intervale Avenue. A film by Irving Rappaport, producer; Ken Howard, director; and Jack Kugelmaas, associate producer. 1983, 16mm, color, 65 minutes. Catalog #430. Distributed by Ergo Media, Inc., P.O. Box 2037, Teaneck, NJ 07666, tele. 201–692–0404.

Some Babies Die. A film by Martyn Landon Down. Australia, 16mm, color, 54 minutes. Distributed by The University of California Extension Media Center, 2176 Shattuck Avenue, Berkeley, CA 94704, tele. 415–642–1340. Price: 16mm—purchase $850, rental $60; video—purchase $450, rental $60.

El Sebou’: The Egyptian Birth Ritual. A film by Fadwa El Guindi; produced by El Nil Research Project; co‐sponsored by the Office of Folklife, Smithsonian Institution. 1986, 16mm, color, 27 minutes. Distributed by El Nil Research Project, 1157 Beverwil Drive, Los Angeles, CA 90035, tele. 213–553–5645. Price: 16mm—purchase $570, rental $70; video—purchase $370. Screenings: Society for Visual Anthropology (1987 Award for Excellence); 1987 Margaret Mead Film Festival; Royal Anthropological Institute (1988 Commendation).

The Making of El Sebou‘

Classified People. Yolande Zauberman, director; produced by OBSESSION/INA/CNC/ FR3‐TOULOUSE; Dewald Aukema, camera; Tony Bensusan, sound; Jean‐François Naudon, editor. 1987, 16mm, color, 53 minutes. Distributed by TELEMONDIS, 15, rue Mesnil, 75016, Paris, tele. 47–27–03–84, telex: 649 078 TELMOND. In U.S., distributed by Filmmaker's Library, 124 E. 40th Street, New York, NY 10016, tele. 212–355–6545. Price: 16mm—rental only $150; video (½″ or ¾″)—purchase $75, rental $75. Screenings: Festival of Women's Films at Créteil (Prix de Jury); Festival of Young Directors at Belfort (Prix de Publique); Bilan du Film Ethnographique 1988 (Prix Nanook/Grand Prix); 1988 Cinéma du Réel; 1987 Margaret Mead Film Festival; U.S. Public Television.

To Cross the Border: An interview with Filmmaker Yolande Zauberman, Paris, May 1988.  相似文献   
106.
The mouse genome consists of six functional actin genes of which the expression patterns are temporally and spatially regulated during development and in the adult organism. Deletion of beta-actin in mouse is lethal during embryonic development, although there is compensatory expression of other actin isoforms. This suggests different isoform specific functions and, more in particular, an important function for beta-actin during early mammalian development. We here report a role for beta-actin during neural crest ontogeny. Although beta-actin null neural crest cells show expression of neural crest markers, less cells delaminate and their migration arrests shortly after. These phenotypes were associated with elevated apoptosis levels in neural crest cells, whereas proliferation levels were unchanged. Specifically the pre-migratory neural crest cells displayed higher levels of apoptosis, suggesting increased apoptosis in the neural tube accounts for the decreased amount of migrating neural crest cells seen in the beta-actin null embryos. These cells additionally displayed a lack of membrane bound N-cadherin and dramatic decrease in cadherin-11 expression which was more pronounced in the pre-migratory neural crest population, potentially indicating linkage between the cadherin-11 expression and apoptosis. By inhibiting ROCK ex vivo, the knockout neural crest cells regained migratory capacity and cadherin-11 expression was upregulated. We conclude that the presence of beta-actin is vital for survival, specifically of pre-migratory neural crest cells, their proper emigration from the neural tube and their subsequent migration. Furthermore, the absence of beta-actin affects cadherin-11 and N-cadherin function, which could partly be alleviated by ROCK inhibition, situating the Rho-ROCK signaling in a feedback loop with cadherin-11.  相似文献   
107.
The presence of muscarinic receptors in sheep and rat pineals was detected by binding of [3H]quinuclidinyl benzilate ([3H]QNB), a potent and specific muscarinic antagonist. [3H]QNB binding to sheep pineal membrane resuspensions was saturable and reversible, with a rate constant for association at 37°C of 6×108M?1min?1 and a rate constant for dissociation of 1×10?2min?1. Kinetic and saturation experiments yielded an equilibrium dissociation constant of 13–18 pM and a concentration of binding sites equivalent to 1.1 pmol/g of original wet weight. This is only about 5% of the level of β-adrenergic receptors. Competition by a variety of cholinergic drugs confirmed the muscarinic nature of the binding sites. Experiments in rats failed to detect a significant decrease in pineal [3H]QNB binding following bilateral superior cervical ganglionectomy, suggesting that the binding sites are not localized exclusively on sympathetic terminals.  相似文献   
108.
109.
Two experiments are described which investigate the orientational consequences of flocking in homing pigeons Columba livia. Previous experiments have shown that homing pigeons placed inside a clear-sided release box for 5 min before release from a familiar site have enhanced ground homing speed compared with those placed in an opaque-sided box. It is assumed that previewing the surrounding landscape allows for faster homing since a bird denied this information must accumulate the knowledge on release. In experiment 1, using the same technique developed in these experiments but releasing the birds in pairs we showed that within familiar areas, homing pigeons can exploit a partner that has acquired more information, allowing them to home more quickly. In experiment 2 we attempted to test three potential strategies which may occur during homing flights. The results do not conclusively distinguish between these three mechanisms but suggest that orientation of the pairs of birds is most likely to have resulted from a compromise of individual tendencies, or from following the best homer, but not from following a ‘governing leader’. The consequence of these mechanisms is discussed.  相似文献   
110.
We examine the extent to which the assumptions underlying line transect sampling are satisfied in shipboard surveys of crabeater seals ( Lobodon carcinophaga ) hauled out on the Antarctic pack-ice. Measurement of the perpendicular distance of seal groups from the ship with an electronic inclinometer fitted to a rifle stock was unbiased. Crabeater seals showed little movement in response to the approaching ship. Movement away from the ship by seals close to the ship's track was partially responsible for a relative lack of sightings close to the transect-line, but otherwise had little effect on the sighting histogram. Minor deviations from the transect direction to avoid running over seals violated the assumption of uniform distribution of groups, and contributed to a relative lack in sightings close to (<40 m) the transect-line. We estimate that 5%-10% of seal groups close to the transect-line were not sighted by bridge observers prior to passing abeam of the ship, but most of these missed groups were likely to have been sighted some distance behind-abeam. Shipboard transects provided a biased sample of four environmental features known to be related to crabeater seal abundance because of logistical difficulties in the ship traversing along straight transects through thick ice. Calculation of transect length L from successive GPS locations was mildly sensitive to the frequency of locations. We provide analytical recommendations to reduce or eliminate the effect of assumption violation when present and hence minimize bias in abundance estimation.  相似文献   
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