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71.
We report the first records of the western gray squirrel ( Sciurus griseus ) from Modoc County and eastern Lassen County in northeastern California. Specimens from Modoc County represent the first records of the species from the Great Basin geographic province. We conclude that these records represent a range expansion based upon previous fieldwork that did not report the species in the region. 相似文献
72.
Annual plant populations in norhtwestern New Mexico were found to be spatially and temporally highly variable. During favorable years annual plant species have patterns of dominance and diversity that are different from those of perennial species. Measurement of perennial plant diversity in plant communities is a poor predictor of productivity. Both perennial and annual components of plant communities should be considered in measurements of diversity and productivity. 相似文献
73.
Artemisia tridentata/Symphoricarpos oreophilus and Symphoricarpos oreophilus/Artemisia tridentata plant associations were studied in northeastern Nevada. A 60-stand reconnaissance followed by a detailed study of 37 stands differentiated five important habitat types using an association table approach. Data reduction with DECORANA and TWINSPAN also described five plant associations that were differentiated by species occurrence and geographical distribution. All stands were found at elevations between 2,200 and 3,100 m in areas where snow accumulates and is late to melt. Stands are found on 15 families of soils that are relatively deep, often skeletal, dark colored, and productive. The dominant perennial grasses included Agropyron spicatum, Agropyron trachycaulum, and Festuca idahoensis. 相似文献
74.
75.
Adriano Cavalleri Mariana F. Lindner Milton de S. Mendonça Jr 《Journal of Natural History》2016,50(21-22):1389-1410
The tribe Haplothripini includes a large diversity of Thysanoptera–Phlaeothripinae, comprising more than 550 species in about 35 genera. They are characterised by having a maxillary bridge in the head, prosternal basantra well developed and fore wings with a median constriction. Members of this group are present in all geographical regions, but are particularly poorly studied in Central and South America. In this study, we describe a new genus and species, Myrciathrips variabilis gen. et. sp. nov., and a new Haplothrips species; and propose two new combinations: Karnyothrips grassoi (De Santis), and Mirothrips vespicola (De Santis). A key to the nine Haplothripini genera now recognised from Central and South America is provided, together with an updated key to Haplothrips and Mirothrips species. A total of 45 species of Haplothripini are now recognised from Central and South America, and a list of these and their distributions is given. The genera Karnyothrips, Haplothrips and Leptothrips are the most commonly encountered, and some exotic species such as Androthrips ramachandrai and Dolichothrips indicus are now widespread in the Americas. 相似文献
76.
James T. Ziegenfuss Jr. Robert F. Munzenrider Joan Lartin-Drake 《Systemic Practice and Action Research》1998,11(6):575-597
Many health care organizations are currently engaged in changing the design of their health care services delivery system. The issues of cost containment, quality, and access are prominent. This paper reports on the impact of the implementation of a new organization design at one university hospital. The organization change effort (named HORIZONS) was a five year project funded in part by the Robert Wood Johnson Foundation and the Pew Charitable Trusts. In a changing health care environment, the project was undertaken with three goals in mind: (1) to maintain and enhance quality of patient care; (2) to improve the quality of working life; and (3) to accomplish this in a budget neutral manner. Initiated as a program to strengthen hospital nursing, the project became a patient-focused redesign effort encompassing both clinical and administrative affairs. The core ideas of the project approach included systems thinking, interactive planning and idealized design. This evaluation reports on the project's progress after six years. 相似文献
77.
C. van Duijn Jr 《Cellular and molecular life sciences : CMLS》1978,34(8):1102-1103
Summary Photosensitivity of bull spermatozoa increases with decreasing pH in the investigated range of pH 5.2–9.0. 相似文献
78.
Corey E. Roelke Jose A. Maldonado Blake W. Pope Thomas J. Firneno Jr Travis J. Laduc Toby J. Hibbitts 《Journal of Natural History》2018,52(13-16):1017-1027
ABSTRACTWe examined genetic relationships among individuals and populations of the species Holbrookia lacerata, the spot-tailed earless lizard, using whole mitochondrial genomes. Lizards were collected from south, central and west Texas. We found significant amounts of genetic structure among populations and evidence of two major reciprocally monophyletic groups of spot-tailed earless lizards in Texas. Holbrookia lacerata lacerata occurs on the Edwards Plateau and adjacent regions of West Texas north of the Balcones Escarpment, while Holbrookia lacerata subcaudalis occurs in South Texas and adjacent Mexico south of the Balcones Escarpment. These two recognised subspecies correspond to the two clades we discovered. Holbrookia l. lacerata occupies much of its historical range at sometimes high population densities, while populations of H. l. subcaudalis appear to be highly fragmented based on recent observations compared to their historical range. 相似文献
79.
Sanjay Kumar Bharti Irfan Khan Taraswi Banerjee Joshua A. Sommers Yuliang Wu Robert M. Brosh Jr. 《Cellular and molecular life sciences : CMLS》2014,71(14):2625-2639
In 2010, a new recessive cohesinopathy disorder, designated Warsaw breakage syndrome (WABS), was described. The individual with WABS displayed microcephaly, pre- and postnatal growth retardation, and abnormal skin pigmentation. Cytogenetic analysis revealed mitomycin C (MMC)-induced chromosomal breakage; however, an additional sister chromatid cohesion defect was also observed. WABS is genetically linked to bi-allelic mutations in the ChlR1/DDX11 gene which encodes a protein of the conserved family of Iron–Sulfur (Fe–S) cluster DNA helicases. Mutations in the budding yeast ortholog of ChlR1, known as Chl1, were known to cause sister chromatid cohesion defects, indicating a conserved function of the gene. In 2012, three affected siblings were identified with similar symptoms to the original WABS case, and found to have a homozygous mutation in the conserved Fe–S domain of ChlR1, confirming the genetic linkage. Significantly, the clinically relevant mutations perturbed ChlR1 DNA unwinding activity. In addition to its genetic importance in human disease, ChlR1 is implicated in papillomavirus genome maintenance and cancer. Although its precise functions in genome homeostasis are still not well understood, ongoing molecular studies of ChlR1 suggest the helicase plays a critically important role in cellular replication and/or DNA repair. 相似文献
80.
We record eight species of exotic fishes as established, reproducing populations in certain springs in Clark, Lincoln, and Nye counties. Nevada. These include an unidentified species of Hypostomus, Cyprinus carpio, Poecilia mexicana, Poecilia reticulata, a Xiphophorus hybrid, and Cichlasoma nigrofasciatum. Tilapia mariae, established in a spring near the Overton Arm of Lake Mead, and Tilapia zilli, established in a golf course pond in Pahrump Valley, are recorded for the first time from Nevada waters. Though populations of transplanted Gambusia affinis persist, other populations of Poecilia latipinna are apparently no longer extant. Cichlasoma severum, Notemigonus crysoleucas, Poecilia latipinna, and Carassius auratus were apparently eradicated from Rogers Spring in 1963. 相似文献