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As one of the main components of a high-precision time measurement system, the time-to-digital converter (TDC) is widely used in many scientific research fields. A two-stage high-precision and wide-range TDC application-specified integrated circuit (ASIC) based on a differential delay line using delay-locked loop (DLL) technology is presented. The TDC ASIC consists of a coarse measurement stage for expanding the measurement range and a fine measurement stage for high-precision measurement. The coarse stage is achieved by two binary counters with dual edges sampling to avoid the metastable state. The fine stage is achieved by a voltage-controlled delay line (VCDL). The VCDL utilizes differential delay cells to mitigate the susceptibility to the power supply noise and the substrate noise. A DLL is adopted to compensate for variations in process, voltage, and temperature (PVT). The TDC AISC has been fabricated in a 180-nm CMOS technology and tested. A dynamic measurement range of $6.55~\mu $ s and a time resolution of 200 ps are achieved with a reference clock of 312.5 MHz. Test results show that the precision is 65.6-ps root-mean-square (rms), and the differential nonlinearity is within -0.34–0.40 LSB.

Sarcopenia is characterized by progressive loss of muscle mass and function due to aging. DNA methylation has been identified to play important roles in the dysfunction of skeletal muscle. The aim of our present study was to explore the whole blood sample‐based methylation changes of skeletal muscle function‐related factors in patients with sarcopenia. The overall DNA methylation levels were analysed by using MethlTarget™ DNA Methylation Analysis platform in a discovery set consistent of 50 sarcopenic older adults (aged ≥65 years) and 50 age‐ and sex‐matched non‐sarcopenic individuals. The candidate differentially methylated regions (DMRs) were further validated by Methylation‐specific PCR (MSP) in another two independent larger sets and confirmed by pyrosequencing. Receiver operating characteristic (ROC) curve analysis was used to determine the optimum cut‐off levels of fibroblast growth factor 2 (FGF2)_30 methylation best predicting sarcopenia and area under the ROC curve (AUC) was measured. The correlation between candidate DMRs and the risk of sarcopenia was investigated by univariate analysis and multivariate logistic regression analysis. Among 1149 cytosine‐phosphate‐guanine (CpG) sites of 27 skeletal muscle function‐related secretary factors, 17 differentially methylated CpG sites and 7 differentially methylated regions (DMRs) were detected between patients with sarcopenia and control subjects in the discovery set. Further methylation‐specific PCR identified that methylation of fibroblast growth factor 2 (FGF2)_30 was lower in patients with sarcopenia and the level was decreased as the severity of sarcopenia increased, which was confirmed by pyrosequencing. Correlation analysis demonstrated that the methylation level of FGF2_30 was positively correlated to ASMI (r= 0.372, P< 0.001), grip strength (r= 0.334, P< 0.001), and gait speed (r= 0.411, P< 0.001). ROC curve analysis indicated that the optimal cut‐off value of FGF2_30 methylation level that predicted sarcopenia was 0.15 with a sensitivity of 84.6% and a specificity of 70.1% (AUC = 0.807, 95% CI = 0.756–0.858, P< 0.001). Multivariate logistic regression analyses showed that lower FGF2_30 methylation level (<0.15) was significantly associated with increased risk of sarcopenia even after adjustment for potential confounders including age, sex, and BMI (adjusted OR = 9.223, 95% CI: 6.614–12.861, P< 0.001). Our results suggest that lower FGF2_30 methylation is correlated with the risk and severity of sarcopenia in the older adults, indicating that FGF2 methylation serve as a surrogate biomarker for the screening and evaluation of sarcopenia.

This study was conducted to investigate the effects of dietary energy and protein dilution from age 8 to 14 d on growth performance, clinical blood parameters, carcass yield, and tibia parameters of broilers. Treatments were assigned in a completely randomized manner with factorial arrangement (4×4) including 4 levels of energy dilution and 4 levels of protein dilution. All birds were fed the same diet during the remaining period of time. The feeds were weighed every week, and the birds were weighed at 7, 14, and 42 d. At 14 d, blood samples were taken for clinical chemistry measurements, and 4 birds from each replicate were sacrificed to measure carcass yield and tibia parameters at 42 d. From 8 to 14 d, average daily feed intake (ADFI) of the 20% protein dilution group increased significantly compared with that of the 10% protein dilution group (P<0.05). The feed conversion ratio (FCR) of the group with 30% protein dilution and 15% energy dilution creased the most among all treatment groups. From 15 to 42 d, the ADFI and FCR of the 20% protein dilution group were greater than those of the 0 and 10% protein dilution groups (P<0.05), and the FCR of the 15% energy dilution group increased significantly (P<0.05). At 42 d, body weight (BW) of the 15% energy dilution group was less than that of the other groups (P<0.05). Significant interactions were observed in ADFI, FCR, and BW at 42 d of age between energy dilution and protein dilution (P<0.05). At 14 d, serum total protein levels of birds in the 20 and 30% protein dilution groups decreased significantly compared to that of the 10% protein dilution group (P<0.05). Blood urea nitrogen concentration of birds in the 20 and 30% protein dilution groups decreased significantly compared with those in 0 and 10% protein dilution groups (P<0.05). Triacylglycerol concentration of birds in the 20% protein and 10% energy dilution groups decreased significantly compared with that of the 0 dilution group (P<0.05). The carcass yields were unaffected by dilution of energy and protein (P>0.05). The bone breaking strength of the 15% energy dilution group decreased significantly compared with that of the 5% energy dilution group (P<0.05). This study suggested that dietary protein and energy reduced 10% from 8 to 14 d of age can not affect the growth performance and other indexes in broilers.

With the rapid development of scripting language, javascript has been widely used in the application and web development industry.One of the main disadvantages of javascript for developers of commercial applications is the ease by which customers and competitors can study, analyze, and reuse the source code . Therefore, this paper proposes a technique of javascript code obfuscation based on control flow tansformations. The experimental results prove that,its effective protect javascript source code.

In view of the increasingly serious software protection problem, the software protection technology based on code obfuscation is analyzed and researched, and a new software protection system, maze protection is designed and realized. With the principle of maze encryption, this program insert a large number of the complex judgments code between function entry and exit, which change the execution order, enhancing the ability of software protection. On this basis, Anti-debug techniques incorporated into the maze protection, which against the mainstream anti-debugger, increasing the advantage of high anti-reversing, tamper-proof and anti-cracking. Experimental analysis has proved that this maze protection technology was better than other virtual machine protection technologies.

Led die bonder used for bond lead frame and chip is one of the key equipment of led production line. The swing-arm is an important component of led die bonder and its dynamic characteristics will directly affect the piece accuracy. At present, the accuracy and efficiency of led die bonder are limited because of the vibration of the swing-arm. In solving this problem, a three-dimensional finite-element model for swing-arm is built to provide analytical frequencies and vibration modes. Then the modal distribution and vibration mode shapes for swing-arm are obtained after analyzing the modal by ansys10.0. Finally the dynamics effects of this structure by modal frequency and vibration mode are analyzed. The modal analysis of structural would provide the reference to dynamics analysis and structural optimization for swing-arm in practical use.

The objective of this study was to find the specific expressed genes in chicken sperm storage tubules. One hundred and fifty dual-purpose hens at 30 weeks of age were inseminated with 1 × 108spermatozoa on two consecutive days. Eggs were collected and set daily during the 24 days following the latter of two inseminations. Five hens with fertility below 60% were inseminated with fresh semen. Fifteen hens with fertility above 80% were divided into three groups. Fresh semen, frozen dead semen and 0.9% NaCl, respectively, were injected into the vagina of five hens in each group. RNA from the utero-vaginal junction (UVJ) of the hens was reverse transcribed and differentially displayed. Four bands of interest which were expressed in UVJ from hens inseminated with fresh semen or frozen semen but not from hens inseminated with saline were selected, re-amplified, cloned and sequenced. BLAST search showed that band A is similar to part of chromosome 3 (the homology is 9–8%) and the nearest gene to the fragment is 1,722 base pairs up-stream whose product is mitogen- activated kinase. Band B is similar to phosphatidyl inositol glycan anchor biosynthesis gene (PIGK) and the homology is 98%. PIGK is a subunit of glycosylphosphatidylinositol transamidase (GPI8). GPI-linked proteins participate in the release of membrane proteins. Band F is similar to a hypothetical protein gene and the homology is 9–7%. This hypothetical protein belongs to chicken neurexophilin. Band G is similar to fat3 and the homology is 97%. Neurexophilin and fat3 are proteins that function in the nervous system. Taken together these data indicate that hens may regulate sperm storage in UVJ through the nervous system and may release sperm from the UVJ through GPI8.

Abstract: This study was conducted to detect polymorphisms in intron 1 of porcinePOU1F1 (POU domain, class 1, transcription factor1, Pit1, renamed asPOU1F1) by comparative sequencing. Within the intron, 23 sites of variation were identified, including 16 single-nucleotide substitutions, 4 single-nucleotide indels, 2 short (3-bp and 17-bp), and one long (313-bp) indels. Several important regulatory motifs were found within the 313-bp indel byin silico analysis. The 313-bp indel was next genotyped in 11 Chinese native pig breeds and 4 western meat-type pig breeds. The appearance of genotypes varied between breeds: among Chinese native breeds, no AA and AB genotypes were found in Tibetan, Lingao, Min, Rongchang, and Songliao Black pigs, no AA genotype was found in Fenjing and Leping Spotted pigs, whereas in Pietrain and Landrace there were no BB genotypes, and all 19 Duroc pigs were AA homozygotes. The western meat-type pigs had high A allele frequencies and the Chinese pigs had more B alleles, except Jianquhai pigs. A positive association of the AA genotype with birth weight was observed in a commercial pig line. This paper demonstrated that the genetic variation in intron 1 of the pigPOU1F1 gene was high and these polymorphisms may provide useful makers for QTL analysis.

To examine whether or not the regulatory sequence of chicken ovalbumin gene can drive transgene expression specifically in hen oviduct, the authors constructed an oviduct-specific expression vector (pOV), containing 3.0 kilobases (kb) of the 5′-flanking sequence and 3.0 kb of the 3′-flanking sequence of the chicken ovalbumin gene. Jellyfish green fluorescence protein (EGFP) reporter gene and bacterial LacZ reporter gene were respectively inserted into the downstream of the 5′-regulatory region. The recombinants were named as pOVEGFP and pOVLacZ. Two transfer systems, in vitro and in vivo, were used to verify the function of the vector. In vitro, the plasmid DNA pOVEGFP and pEGFP-N1 were transfected respectively by the polyethyle-neimine procedure into the primary chicken oviduct epithelium (PCOE) and fibroblasts cells isolated from laying hens. In vivo, the recombinant vector pOVLacZ was injected into egg-laying hens via wing vein and the tissues were collected for RT-PCR analysis. The results showed that expression of pEGFP-N1 was achieved at low level in oviduct epithelial cells and at high level in fibroblasts, but that the recombinant vector was not expressed in both cells. RT-PCR analysis showed that the LacZ gene was transcribed in the oviduct, but not in the heart, liver, kidney and spleen of the injected hens. Accordingly, the β-galactosidase activity was only detected in the oviduct magnum (116.7 mU/ml) and eggs (16.47 mU/ml). These results indicated that the cloned regulation regions of chicken ovalbumin gene could drive exogenous gene expression specifically in the oviducts of hens. In vivo gene injection via wing vein may serve as a rapid production system of recombinant proteins in chicken eggs. In addition, the cultured primary oviduct cells from laying hens were not efficient temporary expression systems for analyzing the function of regulating elements of ovalbumin gene.