University of Nevada, Reno

About: University of Nevada, Reno is a education organization based out in Reno, Nevada, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 13561 authors who have published 28217 publications receiving 882002 citations. The organization is also known as: University of Nevada & Nevada State University.

Glucose metabolism is altered in the adequately-nourished grand-offspring (F3 generation) of rats malnourished during gestation and perinatal life.

Abstract: To the Editor: A growing number of experimental animal studies have demonstrated the intergenerational effects of foetal/perinatal programming on birth weight, blood pressure and glucose metabolism. Potential explanations for these intergenerational effects include the following: (1) shared genetic attributes of parent and offspring; (2) adverse ‘extrinsic’ environmental conditions that persist across generations; and (3) adverse intrauterine environments that may be propagated across generations [1]. While a large number of animal studies have shown the effects of undernutrition during foetal/perinatal development on the glucose metabolism of exposed animals (F1) in adulthood [2], several studies have shown that glucose metabolism is also altered in the offspring (F2) of foetally malnourished F1 females, even when the F1 females have been well nourished since weaning [3, 4]. Here, we show, for the first time, that the glucose metabolism of the grandoffspring (F3) of female rats malnourished during development is also adversely affected. Sprague–Dawley rats consumed either a nutritionally adequate diet (20% protein; TD 91352; Harlan Teklad, Madison, WI, USA), or an isoenergetic, low-protein diet (8% protein; TD 93033; Harlan Teklad) from day 1 of pregnancy through lactation. Pups that were protein malnourished in utero consumed an adequate unrestricted diet post-weaning. The dams of control pups were adequately nourished throughout pregnancy and their offspring consumed an adequate unrestricted diet postweaning. To conserve animal resources, only one generation of control animals was bred. At ∼70 days of age, control and experimental animals were deprived of food overnight and subjected to an i.p. glucose tolerance test. Animals were killed under CO2 anaesthesia at 0, 30 and 120 min after glucose load (30% w/v; 2 g/kg body weight, i.p.). Blood was collected by cardiac puncture. Four female first-generation (F1) rats, whose mothers were proteinmalnourished both during pregnancy and while nursing, were randomly selected from the experimental group at ∼70 days of age. The selected F1 rats were mated with control breeder males and maintained on the adequate diet throughout gestation and lactation. Their offspring, the F2 generation, also consumed an adequate diet post-weaning. At ∼70 days of age, glucose tolerance tests were conducted on the F2 rats as described above. A final generation of animals (F3) was bred from control breeder males and four randomly selected F2 dams whose mothers (F1) had been protein-malnourished throughout pregnancy and lactation. F3 animals were maintained on the adequate diet and tested as described. This research was approved by the Institutional Animal Care and Use Committee (IACUC) at Arizona State University. Animals were maintained in accordance with the ‘Guide for the Care and Use of Laboratory Animals’ of the National Research Council (7th ed., 1996). As in previous reports [1, 2], the mean (±SEM) birthweight of F1 animals in our study (5.29±0.082 g) was significantly lower (p<0.05) than that of control animals D. C. Benyshek (*) Department of Anthropology, University of Nevada, Las Vegas, NV 89154-5003, USA e-mail: daniel.benyshek@unlv.edu Tel.: +1-702-8952070 Fax: +1-702-8954823

Contemporary tectonic deformation of the Basin and Range province, western United States: 10 years of observation with the Global Positioning System

Abstract: [1] We have estimated patterns and rates of crustal movement across 800 km of the Basin and Range at ∼39° north latitude with Global Positioning System surveys in 1992, 1996, 1998, and 2002. The total rate of motion tangent to the small circle around the Pacific-North America pole of rotation is 10.4 ± 1.0 mm/yr, and motion normal to this small circle is 3.9 ± 0.9 mm/yr compared to the east end of our network. On the Colorado Plateau the east end of our network moves by ∼1–2 mm/yr westerly with respect to North America. Transitions in strain rates delimit six major tectonic domains within the province. These deformation zones coincide with areas of modern seismicity and are, from east to west, (1) east-west extension in the Wasatch Fault zone, (2) low rate east-west extension centered near the Nevada-Utah border, (3) low rate east-west contraction between 114.7°W and 117.9°W, (4) extension normal to and strike-slip motion across the N10°E striking Central Nevada Seismic Zone, (5) right lateral simple shear oriented N13°W inside the Walker Lane Belt, and (6) shear plus extension near the Sierra Nevada frontal faults. Concentration of shear and dilatational deformation across the three westernmost zones suggests that the Walker Lane Belt lithosphere is rheologically weak. However, we show that linear gradients in viscosity and gravitational potential energy can also effectively concentrate deformation. In the Basin and Range, gradients in gravitational potential are spatially anticorrelated with dilatational strain rates, consistent with the presence of horizontal variations in viscosity of the lithosphere.

Initial results from the Mini-TES experiment in Gusev Crater from the Spirit Rover

Abstract: The Miniature Thermal Emission Spectrometer (Mini-TES) on Spirit has studied the mineralogy and thermophysical properties at Gusev crater. Undisturbed soil spectra show evidence for minor carbonates and bound water. Rocks are olivinerich basalts with varying degrees of dust and other coatings. Dark-toned soils observed on disturbed surfaces may be derived from rocks and have derived mineralogy (+/-5 to 10%) of 45% pyroxene (20% Ca-rich pyroxene and 25% pigeonite), 40% sodic to intermediate plagioclase, and 15% olivine (forsterite 45% +/-5 to 10). Two spectrally distinct coatings are observed on rocks, a possible indicator of the interaction of water, rock, and airfall dust. Diurnal temperature data indicate particle sizes from 40 to 80 microm in hollows to approximately 0.5 to 3 mm in soils.