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Abstract: Body measurement traits, influenced by genes and environmental factors, play numerous important roles in the value assessment of productivity and economy. In this study, we investigated the association between genetic polymorphisms of the zinc finger and BTB domain containing 38 gene (ZBTB38) and body measurement traits in native Chinese cattle. Using direct DNA sequencing in 423 individuals of 8 different cattle subpopulations, 9 novel polymorphisms were identified for genotyping within 647bp region of exon 1 of ZBTB38. Linkage disequilibrium and association analysis revealed that two coding exon polymorphisms (2323 G>A and 2325 C>T polymorphisms), missense mutations valine GTC(T) to isoleucine ATC(T), were associated with body length (BL), withers height (WH) and rump length (RL). Furthermore, the analysis of 2323 G>A and 2325 C>T SNP markers shows that there are significant effects on the BL (P=0.0488), WH (P=0.0044) and RL (P=0.0314) in the total population. These results clearly suggest that the ZBTB38 gene is among the target genes for body measurement traits in bovine breeding, and provide data for establishment of an animal model using cattle to study big animal body type. [Copyright &y& Elsevier]

This paper proposes the dynamically controllable current reference (DCCR) technique for a wide input range, transient enhancement current-feedback low dropout regulator (WTELDO) to achieve transient enhancement. Combined with a transient enhanced current mirror (TE-CM) adopting an enhanced active resistance network, this technique which is designed based on dynamic bias improves the slewing rate of the power transistor gate but also increases the loop bandwidth. Finally, this WTELDO can reduce the minimum input voltage due to the current-feedback technique and improve the transient response under the condition of maintaining low quiescent current. This designed WTELDO was fabricated in SMIC 0. 18 μ m CMOS process. The input voltage range is 0.8–2.2 V. The output voltage is 0.64 V. The maximum load current is 50 mA and the static current consumption is about 26 μ A. Its maximum current efficiency is up to 99.948%. The test results show that the overshoot is 117.5 mV and the undershoot is 167.5 mV when the load current is switched between 0 mA and 50 mA within 300 ns under a 100 pF load capacitor. [ABSTRACT FROM AUTHOR]

Although TRPC6 expression is shown to be significantly elevated in a rat model diabetic nephropathy (DN), its expression and role in human DN are unclear. We thus explored the role of TRPC6 in the pathophysiology of tubular epithelial cell injury following DN. HK-2 cells were cultured in a high-glucose medium to induce a DN cell model. Ad-TRPC6 and TRP6 siRNA were transfected to overexpress and knock down TRPC6. We found that TRPC6 expression was significantly upregulated in DN tissues and cells. TRPC6 siRNA inhibited cell proliferation and promoted cell apoptosis in HK-2 cells treated with high glucose, whereas Ad-TRPC6 showed the opposite effect. Furthermore, Ad-TRPC6 significantly promoted release of IL-8 and IL-6. Subsequent experiments demonstrated that the signaling pathway of nuclear factor of activated T cells (NFAT) was activated by Ad-TRPC6 and deactivated by TRPC6 siRNA. The NFAT signaling inhibitor, FK-506, eliminated the effect of TRPC6 on HK-2 cells. These results suggest that TRPC6 was upregulated in DN and could promote cell proliferation and inflammation by inhibiting the NFAT signaling pathway in tubular epithelial cells. [ABSTRACT FROM AUTHOR]

Abstract: Ultrasound technology was used to measure live animal meat traits instead of true carcass meat traits for beef production and cattle breeding by an increasing number of institutions. In this study, we analyzed the association between genetic polymorphisms of proopiomelanocortin (POMC) and ultrasound measurement traits in Chinese cattle. Using direct DNA sequencing in 322 individuals of 7 different cattle subpopulation, 7 SNPs were identified for genotyping within 790bp region of intron 2 and exon 3 of POMC. 6586 T>G in intron 2 and 6769 C>T and 7216 C>T in exon 3 were significantly associated with ultrasound backfat thickness (UBF) (P <0.05) and ultrasound loin muscle area (ULMA) (P <0.01) in the total population; 6694 C>T, 6706 T>C, 6796 C>T and 6810 C>T in exon 3 were significantly associated with ULMA (P <0.0001) in the total population. These results clearly suggest that these SNPs of POMC be benefit for selection of individuals with good quality meat in Chinese cattle breeding program. Following validation in other populations and breeds, these markers could be incorporated into breeding programs to increase the rate of improvement in carcass and meat quality traits. [Copyright &y& Elsevier]

This paper presents a low power fast transient low-dropout regulator (LDO) employing a Super Class-AB operational transconductance amplifier (OTA). The proposed structure not only achieve large charging/discharging current at the gate of power transistor but also a gain factor, which not only shows excellent transient performance but also ensures enough line/load regulation. Without adding addition circuit structure, the proposed LDO demonstrates a comprehensive improvement, including enhanced line/load regulation and transient performance, when compared with conventional counterpart, implemented in 0.18 μ m CMOS technology, the proposed LDO shows a transient voltage variation of 53 mV at Vout for a load step of 10 μ A -200 mA and possesses a line/load regulation of 1.25 mV/V and 100 μ V /mA respectively. [ABSTRACT FROM AUTHOR]

This paper presents a low-power second-order sigma-delta modulator (SDM) for micro-electromechanical systems (MEMS) digital geophones (DGPs). The proposed SDM optimizes the performance of the first stage integrator and uses an adaptive class-AB current recycling operational transconductance amplifier (OTA) to improve the current efficiency. In addition, gain-enhancing circuits are applied in the OTA to increase the DC gain, and the chopper technique is used in the first stage integrator to reduce the flicker noise. The proposed SDM was implemented in the SMIC 0.18 μ m CMOS technology and occupies an area of 0.82 mm2. The simulation results reveal the signal-to-noise ratio (SNR) was 76.46 dB and the effective number of bit (ENOB) was 12.4 bits. Measurements show that the SNR was 57.5 dB and the ENOB was 9.26 bits with a sampling rate of 256 kHz, an oversampling ratio 128, and a signal bandwidth of 1 kHz. The proposed SDM has a supply voltage of 1.8 V and a power consumption of 193.5 μ W, which is suitable for the low-power MEMS DGPs applications. [ABSTRACT FROM AUTHOR]