A low-voltage wide-swing programmable-gain current amplifier

A CMOS low-voltage, wide-swing continuous-time current amplifier is presented. Exhibiting an open-loop architecture, the circuit is composed of transresistance and transconductance stages built upon triode-operating transistors. In addition to an extended dynamic range, the current gain can be programmed within good accuracy by a rapport involving only transistor geometries and tuning biases. Low temperature-drift on gain setting is then expected.In accordance with a 0.35 mum n-well CMOS fabrication process and a single 1.1 V-supply, a balanced current-amplifier is designed for a programmable gain-range of 6 - 34 dB and optimized with respect to dynamic range. Simulated results from PSPICE and Bsim3v3 models indicate, for a 100 muA(pp)-output current, a THD of 0.96 and 1.87% at 1 KHz and 100 KHz, respectively. Input noise is 120 pArootHz @ 10 Hz, with S/N = 63.2 dB @ 1%-THD. At maximum gain, total quiescent consumption is 334 muW. Measurements from a prototyped amplifier reveal a gain-interval of 4.8-33.1 dB and a maximum current swing of 120 muA(pp). The current-amplifier bandwidth is above 1 MHz.

A low-voltage programmable-gain CMOS amplifier with very-low temperature-drift

A new topology for a LVLP variable-gain CMOS amplifier is presented. Input- and load-stage are built around triode-transconductors so that voltage-gain is fully defined by a linear relationship involving only device-geometries and biases. Excellent gain-accuracy, temperature-insensitivity; and wide range of programmability, are thus achieved. Moreover, adaptative biasing improves the common-mode voltage stability upon gain-adjusting. As an example, a 0-40dB programmablegain audio-amplifier is designed. Its performance is supported by a range of simulations. For VDD=1.8V and 20dB-nominal gain, one has Av=19.97dB, f3db=770KHz and quiescent dissipation of 378μW. Over temperatures from -25°C to 125°C, the 0. ldB-bandwidth is 52KHz. Dynamic-range is optimized to 57.2dB and 42.6dB for gains of 20dB and 40dB, respectively. THD figures correspond to -60.6dB@Vout= 1Vpp and -79.7dB@Vout= 0.5 Vpp. A nearly constant bandwidth for different gains is also attained.

A low-voltage programmable-gain current-mode amplifier

A CMOS low-voltage, wide-band continuous-time current amplifier is presented. Based on an open-loop topology, the circuit is composed by transresistance and transconductance stages built around triode-operating transistors. In addition to an extended dynamic range, the amplifier gain can be programmed within good accuracy by the rapport between the aspect-ratio of such transistors and tuning biases Vxand Vy. A balanced current-amplifier according to a single I. IV-supply and a 0.35μm fabrication process is designed. Simulated results from PSPiCE and Bsm3v3 models indicate a programmable gain within the range 20-34dB and a minimum break-frequency of IMHz @CL=IpF. For a 200 μApp-level, THD is 0.8% and 0.9% at IKHz and 100KHz, respectively. Input noise is 405pA√Hz @20dB-gain, which gives a SNR of 66dB @1MHz-bandwidth. Maximum quiescent power consumption is 56μ W. © 2002 IEEE.

Genome-wide association study for feedlot average daily gain in Nellore cattle (Bos indicus)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Prediction of genomic-enabled breeding values and genome-wide association study for feedlot average daily weight gain in Nelore cattle

Pós-graduação em Genética e Melhoramento Animal - FCAV

Genome-wide association with residual body weight gain in Bos indicus cattle

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fractional order and dynamic simulation of a system involving an elastic wide plate

Numerous researchers have studied about nonlinear dynamics in several areas of science and engineering. However, in most cases, these concepts have been explored mainly from the standpoint of analytical and computational methods involving integer order calculus (IOC). In this paper we have examined the dynamic behavior of an elastic wide plate induced by two electromagnets of a point of view of the fractional order calculus (FOC). The primary focus of this study is on to help gain a better understanding of nonlinear dynamic in fractional order systems. © 2011 American Institute of Physics.

Genome-wide association study for birth weight in Nellore cattle points to previously described orthologous genes affecting human and bovine height

Background: Birth weight (BW) is an economically important trait in beef cattle, and is associated with growth- and stature-related traits and calving difficulty. One region of the cattle genome, located on Bos primigenius taurus chromosome 14 (BTA14), has been previously shown to be associated with stature by multiple independent studies, and contains orthologous genes affecting human height. A genome-wide association study (GWAS) for BW in Brazilian Nellore cattle (Bos primigenius indicus) was performed using estimated breeding values (EBVs) of 654 progeny-tested bulls genotyped for over 777,000 single nucleotide polymorphisms (SNPs).Results: The most significant SNP (rs133012258, PGC = 1.34 × 10-9), located at BTA14:25376827, explained 4.62% of the variance in BW EBVs. The surrounding 1 Mb region presented high identity with human, pig and mouse autosomes 8, 4 and 4, respectively, and contains the orthologous height genes PLAG1, CHCHD7, MOS, RPS20, LYN, RDHE2 (SDR16C5) and PENK. The region also overlapped 28 quantitative trait loci (QTLs) previously reported in literature by linkage mapping studies in cattle, including QTLs for birth weight, mature height, carcass weight, stature, pre-weaning average daily gain, calving ease, and gestation length.Conclusions: This study presents the first GWAS applying a high-density SNP panel to identify putative chromosome regions affecting birth weight in Nellore cattle. These results suggest that the QTLs on BTA14 associated with body size in taurine cattle (Bos primigenius taurus) also affect birth weight and size in zebu cattle (Bos primigenius indicus). © 2013 Utsunomiya et al.; licensee BioMed Central Ltd.

Genome-wide association analysis of feed intake and residual feed intake in Nellore cattle

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Wide localized solutions of the parity-time-symmetric nonautonomous nonlinear Schrodinger equation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)