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11.
Harold J. Egoscue 《西北部美国博物学家》2011,36(4)
Collections from several scattered western localities have (1) extended the ranges in Nevada of two sagebrush vole fleas, Oropsylla bacchi johnsoni and Megabothris clantoni prince , (2) provided a second record for Utah of the rarely collected flea, Delotelis telegoni , and (3) included additional examples of unusual and seldom reported host-flea relationships for the area. 相似文献
12.
We evaluated distribution, habitat use, spawning, and species associations of the endangered humpback chub ( Gila cypha ) in the Yampa and Green rivers, Dinosaur National Monument, from 1986 to 1989. Adult and juvenile humpback chub were captured in high-gradient reaches of Yampa and Whirlpool canyons where they were rare ( n = 133, G. robusta ) were widely distributed in eddies, pools, runs, and riffles. Humpback chub ( n = 39) and roundtail chub ( n = 242) in reproductive condition were sympatric in eddy habitats during the 5-6 week period following highest spring runoff. River temperatures at this time averaged about 20 C. Nonnative channel catfish ( Ictalurus punctatus ) were abundant in eddies yielding humpback and roundtail chubs, suggesting a potential for negative interactions between the native and introduced fishes. 相似文献
13.
Harold J. Cook Nicholas H. Steneck Arthur J. Vander Gordon L. Kane 《Annals of science》2013,70(3):323-351
Two overriding considerations shaped the development of early research on the biological effects of microwave radiation—possible medical application (diathermy) and uncertainty about the hazards of exposure to radar. Reports in the late 1940s and early 1950s of hazards resulting from microwave exposure led to the near abandonment of medical research related to microwave diathermy at the same time that military and industrial concern over hazards grew, culminating in the massive research effort known as ‘the Tri-Service program’ (1957–1960). Both the early focus on medical application and the later search for hazards played important roles in dictating how this field of research developed as a science. 相似文献
14.
Harold Issadore Sharlin Stephen G. Brush Harold L. Burstyn Sandra Herbert Michael S. Mahoney Nathan Sivin 《Annals of science》2013,70(1):55-70
A great deal is known about the technical issues surrounding the introduction of Hugo De Vries's mutation theory and the subsequent development of the modern genetical theory of natural selection. But so far little has been done to relate these events to the wider issues of the time. This article suggests that extra-scientific factors played a significant role, and substantiates this by comparing De Vries's respect for the original Darwinian spirit with Thomas Hunt Morgan's use of the mutation theory as part of an attack on the whole philosophy of Darwinism. In particular, it is argued that Morgan's attitude was dictated by his moral objections to the picture of a world dominated by struggle. 相似文献
15.
Harold J. Egoscue 《西北部美国博物学家》2011,41(3)
Three specimens of Microdipodops megacephalus nasutus were captured in the Wassuk Mountains of western Mineral County, Nevada, which provide a second place of occurrence for the subspecies and a new altitudinal record of 2455 m for the genus. This is the first time this species has been found in the pinyon-juniper belt. 相似文献
16.
Harold J. Egoscue 《西北部美国博物学家》2011,37(1)
The sagebrush vole flea ( Megabothris clantoni princei Hubbard) is reported from Utah for the first time, based on collections made in Tooele County. Distribution of the flea Megabothris abantis in the Bonneville Basin is limited to the Oquirrh Mountains, where its presence appears to be determined by the occurrence of the western jumping mouse. 相似文献
17.
A study was made of the soil mites from under different vegetative types near a coal - burning power plant in the Yampa Valley near Hayden, Colorado. The following new species of oribatids were found: Zygoribatula apletosa n.sp., Multoribates haydeni n.sp., Paraphauloppia cordylinosa n.sp., Passalozetes moniles n.sp. 相似文献
18.
Van Fraassen, like Popper before him, assumes that confirmation and disconfirmation relations are logical relations and thus hold only among abstract items. This raises a problem about how experience, for Popper, and observables, for van Fraassen, enter into epistemic evaluations. Each philosopher offers a drastic proposal: Popper holds that basic statements are accepted by convention; van Fraassen introduces his “pragmatic tautology.” Another alternative is to reject the claim that all evaluative relations are logical relations. Ayer proposed this option in responding to Popper, as did Sosa in a different context. I argue that this option should be pursued and propose a line of research that the option suggests. 相似文献
19.
Infantile-onset symptomatic epilepsy syndrome caused by a homozygous loss-of-function mutation of GM3 synthase 总被引:8,自引:0,他引:8
Simpson MA Cross H Proukakis C Priestman DA Neville DC Reinkensmeier G Wang H Wiznitzer M Gurtz K Verganelaki A Pryde A Patton MA Dwek RA Butters TD Platt FM Crosby AH 《Nature genetics》2004,36(11):1225-1229
We identified an autosomal recessive infantile-onset symptomatic epilepsy syndrome associated with developmental stagnation and blindness. Assuming a founder effect in a large Old Order Amish pedigree, we carried out a genome-wide screen for linkage and identified a single region of homozygosity on chromosome 2p12-p11.2 spanning 5.1 cM (maximum lod score of 6.84). We sequenced genes in the region and identified a nonsense mutation in SIAT9, which is predicted to result in the premature termination of the GM3 synthase enzyme (also called lactosylceramide alpha-2,3 sialyltransferase). GM3 synthase is a member of the sialyltransferase family and catalyzes the initial step in the biosynthesis of most complex gangliosides from lactosylceramide. Biochemical analysis of plasma glycosphingolipids confirmed that affected individuals lack GM3 synthase activity, as marked by a complete lack of GM3 ganglioside and its biosynthetic derivatives and an increase in lactosylceramide and its alternative derivatives. Although the relationship between defects in ganglioside catabolism and a range of lysosomal storage diseases is well documented, this is the first report, to our knowledge, of a disruption of ganglioside biosynthesis associated with human disease. 相似文献
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