Systematic Review of the Texas Pocket Gopher, \u3ci\u3eGeomys personatus\u3c/i\u3e (Mammalia: Rodentia)

The Texas pocket gopher (Geomys personarus), which occupies a range in southern Texas and extreme northeastern Tamaulipas, was examined for morphological variation. Univariate and multivariate analyses were used to determine age, secondary sexual, individual, and geographic variation. Significant differences were found among the three age classes and between the sexes for 12 of 13 cranial measurements. Males displayed higher individual variation than females. Distributions of the six previously recognized subspecies (fallax, fuscus, maritimus, megapotamus, personatus, and streckeri) were examined. An additional subspecies is recognized and described. Of the seven subspecies of G. personatus, fuscus and streckeri form a group distinct from other subspecies

Results of the Alcoa Foundation-Suriname Expeditions. II. Additional Records of Bats (Mammalia: Chiroptera) from Suriname

The occurrence of 14 species of bats previously unknown in Suriname are documented, making a total of 85 species of bats known to occur in the country. The new records include Pteronotus personatus, Chrotopterus auritus, Micronycteris daviesi, M. sylvestris, Phyllostomus latifolius, Choeroniscus godmani, C. intermedius, Lionycteris spurrelli, Mesophylla macconnelli, Vampyressa brocki, Vampyrops brachycephalus, Rhogeessa tumida, Molossops abrasus, and M. greenhalli. Additional information is provided on several species of bats already known to occur in Suriname, including Micronycteris minuta, M. nicefori, Phylloderma stenops, Tonatia bidens, T. brasiliense, T. carrikeri, Vampyrum spectrum, Anoura caudifer, Carollia brevicauda, Rhinophylla pumilio, Vampyressa bidens, and Lasiurus ega

Systematic Review of the Texas Pocket Gopher, \u3ci\u3eGeomys personatus\u3c/i\u3e (Mammalia: Rodentia)

The Texas pocket gopher (Geomys personarus), which occupies a range in southern Texas and extreme northeastern Tamaulipas, was examined for morphological variation. Univariate and multivariate analyses were used to determine age, secondary sexual, individual, and geographic variation. Significant differences were found among the three age classes and between the sexes for 12 of 13 cranial measurements. Males displayed higher individual variation than females. Distributions of the six previously recognized subspecies (fallax, fuscus, maritimus, megapotamus, personatus, and streckeri) were examined. An additional subspecies is recognized and described. Of the seven subspecies of G. personatus, fuscus and streckeri form a group distinct from other subspecies

Analytical and Experimental Studies of Thermal Noise in MOSFET\u27s

An analysis of the channel thermal noise in MOSFET\u27s, based on the one-dimensional charge sheet model, is presented. The analytical expression is valid in the strong, moderate, and weak inversion regions. The body effect on the device parameters relevant to the thermal noise is discussed. A measurement technique as well as experimental results of P- and N-MOSFET\u27s of a 1.2 µm radiation hard CMOS process are presented. The calculated channel thermal noise coefficient gamma as in id2/Δf=4kT γ gdo agrees well with experimental data for effective device channel length as short as 1.7µm

Karyology and Morphometrics of Three Species of \u3ci\u3eAkodon\u3c/i\u3e (Mammalia: Muridae) from Northwestern Argentina

Chromosomal and morphometric studies were conducted on a sample from an assemblage of Akodon spp. occurring in various patterns of sympatry from the provinces of Catamarca, Jujuy, Salta, and Tucumán, Argentina. Results showed three distinct morphometric groups based upon size. Size also varied with age, but there were no significant differences in measurements of males and females. The three morphometric groups have distinct karyotypes. Akodon caenosus Thomas is the smallest of the three, and has a karyotype of 2n = 34, FN = 40. A. boliviensis tucumanensis J. A. Allen is intermediate in size and has 2n = 40, FN = 40,41. Three variations in centromeric position of the X chromosomes and two autosome arm numbers were found. A. varius simulator Thomas is the largest in size, has a distinctive white chin-spot, and has 2n = 41,42 and FN = 42. Variation in diploid number is apparently due to centric fission or fusion

Karyology and Morphometrics of Three Species of \u3ci\u3eAkodon\u3c/i\u3e (Mammalia: Muridae) from Northwestern Argentina

Chromosomal and morphometric studies were conducted on a sample from an assemblage of Akodon spp. occurring in various patterns of sympatry from the provinces of Catamarca, Jujuy, Salta, and Tucumán, Argentina. Results showed three distinct morphometric groups based upon size. Size also varied with age, but there were no significant differences in measurements of males and females. The three morphometric groups have distinct karyotypes. Akodon caenosus Thomas is the smallest of the three, and has a karyotype of 2n = 34, FN = 40. A. boliviensis tucumanensis J. A. Allen is intermediate in size and has 2n = 40, FN = 40,41. Three variations in centromeric position of the X chromosomes and two autosome arm numbers were found. A. varius simulator Thomas is the largest in size, has a distinctive white chin-spot, and has 2n = 41,42 and FN = 42. Variation in diploid number is apparently due to centric fission or fusion

Noise Spectral Density Measurements of a Radiation Hardened CMOS Process in the Weak and Moderate Inversion

We have measured the noise of MOS transistors of the United Technology Microelectronics Center (UTMC) 1.2 µm radiation hardened CMOS P-well process from the weak to moderate inversion region. The noise power spectral densities of both NMOS and PMOS devices were measured from 1 KHz to 50 MHz. The bandwidth was chosen such that the important components of the spectral densities such as the white thermal noise and the l/f noise could be easily resolved and analyzed in detail. The effects of different device terminal DC biases and channel geometries on the noise are described