ABSTRACT To effectively develop and utilize high-quality Tianfu broilers, this study evaluated the morphological and structural characteristics of the immune organs of such broilers with different strains (HS1 and HS2) at different developmental stages and analyzed the distribution of mast cells by toluidine blue staining. Moreover, the localization and expression of immunoglobulin, complement C3, C4 and CD3 in immune organs were also detected. The results showed that although there was no significant difference in the development of immune organs in the HS1 and HS2, the number of lymphatic follicles and capsule thickness in the spleen and bursa of Fabricius in HS1 were greater than those in HS2. Additionally, the number of mast cells in the spleen of HS1 was greater at Day 1 and Day 21 and was significantly higher than that of HS2 (p<0.05); the number of mast cells in the bursa of Fabricius reached 9.17 on Day 7, which was significantly higher than that of HS2 (p<0.05). Moreover, the serum IgA and IgM levels in HS1 were higher than those in HS2 on Day 14 and 21 (p<0.05). In addition, the complement C3 content in HS1 was significantly or extremely significantly higher than that in HS2 on Days 1, 14 and 21 (p<0.01, p<0.05), respectively, but significantly lower than in HS2 on Day 7 (p<0.05). These results indicated that the disease resistance of the HS1 line was stronger than that of the HS2 line, which lays a foundation for future disease- resistance breeding of Tianfu broilers.

ABSTRACT Heparan sulfate proteoglycans (HSPGs) are present on the cell surface and in the extracellular matrix in all metazoans. HSPGs interact with growth factors and receptors through heparan sulfate (HS) chains. The sulfation pattern of heparan sulfate chains influences signaling events mediated by heparan sulfate proteoglycans located on the cell surface. SULF1 and SULF2 are two endo-sulfatases that can cleave specific 6-O-sulfate groups within the heparan chains. To determine their possible roles in tissues and satellite cells in vitro, their expression pattern was examined in tissues from 40-day-old chickens and in satellite cells from the breast muscles of 1-week-old and 2-week-old chickens using RT-PCR and immunocytochemistry analyses. The SULF1 and SULF2 transcripts were widely distributed in various tissues. Upon increasing culture times in chicken´s primary skeletal muscle satellite cells, SULF1 and SULF2 expression in 1-week-old chickens was significantly higher than in 2-week-old chickens, suggesting that sulfatases play a key role in satellite cell development. Therefore, our findings increase our knowledge of sulfatase expression diversity and provide a solid basis for further research concerning this molecular mechanism.

ABSTRACT There is increasing evidence that bone morphogenetic protein 6 (BMP6) plays critical roles in regulating various stages of ovarian follicle development in mammals. However, the mechanisms of regulation of BMP6 in the chicken ovary remain unclear. In this study, mRNA and protein expression level of BMP6 in chicken ovarian follicles at different development stages were determined by qRT-PCR and western blot separately. Different concentrations of BMP6 protein and FSH were added to the culture medium, and the effects to proliferation of granulose cells were detected, further effect on expression pattern of progesterone synthesis associated genes were also analyzed by qRT-PCR and Western blotting and the secretion of progesterone was detected by ELISA. The results showed that mRNA and protein expression level of BMP6 increased significantly in the follicle with the development of follicle (p<0.05) and reached a peak at F1 follicle. Adding concentration of 50ng/ml and 100ng/ml of BMP6 protein promoted significantly the proliferation of granulosa cells (p<0.05), as well as up-regulated the expression of Steroid hormone synthesis acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) genes in mRNA and protein level. Meanwhile, the secretion of progesterone was significantly higher in the group that added BMP6 and FSH separately than blank control group (p<0.05) and reached a peak in the group that both added BMP6 and FSH. Collectively, these findings highlight that BMP6 is associated with proliferation of follicular cells and the synthesis of progesterone, which indicated that it took an important role in the follicular development of chicken.

We propose a technique that enhances the bandwidth efficiency of the two transmit antenna differential space-time block code (DSTBC) by use of space-time block code (STBC) expansion and trellis coding. STBC expansion is realized by expanding the conventional Alamouti STBC using unitary matrix transformation. This is followed by trellis code-aided mapping of additional bits to space-time codes of the expanded set. Trellis code-aided mapping of additional bits enhances the bandwidth efficiency of the proposed DSTBC scheme. The proposed scheme sends more information bits in each transmitted space-time code than the conventional differential detection-aided DSTBC (CDD-DSTBC) scheme, and yet retains the same error performance. For each additional bit sent with the transmitted space-time codeword, the proposed scheme using 16QAM achieves a 12.5% increase in bandwidth efficiency, while the scheme using 64QAM realises an 8.3% increase. Simulation results demonstrate that the error performance of the proposed scheme tightly matches that of CDD-DSTBC with improvement in bandwidth efficiency. The bandwidth efficiency is enhanced at the expense of a moderate increase of the computational complexity at the receiver.

Multiple-input multiple-output (MIMO) systems have attracted a vast amount of interest, due to improvements offered in capacity and diversity. However, several challenges still remain. Single transmit antenna selection with modulation (STASM) is an important closed-loop variant of MIMO, and addresses several of its challenges, while achieving full-diversity. On this note, the average symbol error probability (ASEP) of STASM with M-ary quadrature amplitude modulation (M-QAM) and M-ary phase shift keying (M-PSK) is formulated and validates the Monte Carlo simulation results. The formulated ASEP expressions are relatively easy to evaluate. Euclidean distance-based antenna selection for spatial modulation (EDAS-SM) is an innovative closed-loop MIMO scheme that provides many advantages. However, since STASM achieves a full-diversity compared to EDAS-SM, there exists a cross-over point after which its error performance is superior to the latter. For multiple receive antennas, the cross-over point only occurs in the moderate-to-high signal-to-noise ratio region, which may be difficult to achieve in practice. Hence, an adaptive transmit mode switching system based on STASM and EDAS-SM as transmission candidates is proposed. A selection criterion for the transmission candidate is based on minimizing the instantaneous symbol error probability in every transmission interval. By switching between STASM and EDAS-SM, the proposed scheme minimizes the ASEP.

In this study, the authors propose two low-complexity near-maximum-likelihood (ML) detection algorithms for spatial modulation (SM) systems, employing the new multiple-ring star-M-ary quadrature amplitude modulation (MR-STAR-MQAM) constellation. The proposed detectors exploit the specific orientation of MR-STAR-MQAM, in order to avoid searching across all constellation points. As a result, the computational complexity is independent of both the constellation size and the number of rings presented in MR-STAR-MQAM. In addition, these detectors are generalized and can be applied to the entire star-MQAM family. The Monte Carlo simulation results demonstrate that the proposed detection algorithms achieve the same average bit error rate (ABER) as ML detection for SM but at a much lower computational complexity. For example, in a 4x4, 2R-STAR-16QAM aided SM system, the proposed optimal and sub-optimal detectors achieve an 88.8% and 90.5% reduction in computational complexity, respectively, compared to the ML detector. Furthermore, the simulation results are supported by a closed-form union-bound theoretical ABER expression.

Space shift keying (SSK) modulation is a special case of conventional spatial modulation (SM), where the amplitude and/or phase modulation symbols are eliminated from the transmission process so as to reduce complexity. However, high spectral efficiencies are difficult to achieve with SSK. At the same time, the spectral efficiency of SM can be further improved. On this note, to further enhance the spectral efficiencies of both SM and SSK, quadrature SM (QSM) and Bi-SSK modulations, respectively, were proposed. In coded channels, typically soft-output detection coupled with soft-input channel decoding yields significant signal-to-noise ratio (SNR) gain. Hence, in this paper, we propose soft-output maximum-likelihood detectors (SOMLD) for SSK, Bi-SSK and QSM modulated systems. Monte Carlo simulation results demonstrate that the error performances of the proposed SOMLD schemes closely match with that of their hard-decision maximum-likelihood detector counterparts in uncoded channels; while, significant SNR gains are yielded in coded channels.

A special case of conventional spatial modulation (SM) is demonstrated in space shift keying (SSK) modulation, where the amplitude and/or phase modulation symbols are eliminated from the transmission process so as to reduce system complexity. However, the spectral efficiencies of both schemes increase only logarithmically. Hence, large antenna arrays are required to achieve high spectral efficiencies. To reduce the transceiver overhead, while achieving improved spectral efficiencies in both SM and SSK, generalised SM (GSM) and generalised SSK (GSSK), respectively, were proposed. Typically, in coded channels, soft-output detection coupled with soft-input channel decoding yields significant signal-to-noise ratio (SNR) gain. Hence, in this paper, we propose soft-output maximum-likelihood (ML) detectors (SOMLDs) for the GSM and GSSK schemes, with an aim to further improve the error performance of the systems. Monte Carlo simulation results demonstrate that the error performance of the proposed SOMLD schemes closely match with that of their hard-decision ML detector counterparts in uncoded channels; while significant SNR gains are yielded in coded channels.

ABSTRACT BMP6, a member of the subfamilies of the morphogenetic proteins (BMPs), plays a crucial role in osteogenic and chondrocyte differentiation in vitro and stimulates chondrogenesis, making chondrocytes differen-tiate on their terminal stage. The objective of this study is to explore the relationship between polymorphism of BMP6 gene and slaughter traits in chicken respectively. We screened the exonic and intronic regions of BMP6 gene by DNA pool construction and amplified DNA fragment by PCR, and finally, we got nine SNPs. Association analysis revealed that BMP6 had no significant association among all slaughter traits in Yellow bantam chicken. However, BMP6 had a significant difference with femur weight, tibia weight, femur length (p<0.05), and was extremely significant with tibia length (p<0.01) in Avian chicken. Moreover, femur perimeter also had significant correlation with BMP6 in Avian chicken. These results provide useful information for further investigation on the function of chicken BMP6 gene.

The present study screened potential genes related to lung adenocarcinoma, with the aim of further understanding disease pathogenesis. The GSE2514 dataset including 20 lung adenocarcinoma and 19 adjacent normal tissue samples from 10 patients with lung adenocarcinoma aged 45-73 years was downloaded from Gene Expression Omnibus. Differentially expressed genes (DEGs) between the two groups were screened using the t-test. Potential gene functions were predicted using functional and pathway enrichment analysis, and protein-protein interaction (PPI) networks obtained from the STRING database were constructed with Cytoscape. Module analysis of PPI networks was performed through MCODE in Cytoscape. In total, 535 upregulated and 465 downregulated DEGs were identified. These included ATP5D, UQCRC2, UQCR11 and genes encoding nicotinamide adenine dinucleotide (NADH), which are mainly associated with mitochondrial ATP synthesis coupled electron transport, and which were enriched in the oxidative phosphorylation pathway. Other DEGs were associated with DNA replication (PRIM1, MCM3, and RNASEH2A), cell surface receptor-linked signal transduction and the enzyme-linked receptor protein signaling pathway (MAPK1, STAT3, RAF1, and JAK1), and regulation of the cytoskeleton and phosphatidylinositol signaling system (PIP5K1B, PIP5K1C, and PIP4K2B). Our findings suggest that DEGs encoding subunits of NADH, PRIM1, MCM3, MAPK1, STAT3, RAF1, and JAK1 might be associated with the development of lung adenocarcinoma.

We investigated the prognostic effects of high-flux hemodialysis (HFHD) and low-flux hemodialysis (LFHD) in patients with chronic kidney disease (CKD). Both an electronic and a manual search were performed based on our rigorous inclusion and exclusion criteria to retrieve high-quality, relevant clinical studies from various scientific literature databases. Comprehensive meta-analysis 2.0 (CMA 2.0) was used for the quantitative analysis. We initially retrieved 227 studies from the database search. Following a multi-step screening process, eight high-quality studies were selected for our meta-analysis. These eight studies included 4967 patients with CKD (2416 patients in the HFHD group, 2551 patients in the LFHD group). The results of our meta-analysis showed that the all-cause death rate in the HFHD group was significantly lower than that in the LFHD group (OR=0.704, 95%CI=0.533-0.929, P=0.013). Additionally, the cardiovascular death rate in the HFHD group was significantly lower than that in the LFHD group (OR=0.731, 95%CI=0.616-0.866, P<0.001). The results of this meta-analysis clearly showed that HFHD decreases all-cause death and cardiovascular death rates in patients with CKD and that HFHD can therefore be implemented as one of the first therapy choices for CKD.

ABSTRACTThis study aimed at examining the effect of overfeeding on the activity of the mTOR pathway in the liver and muscle tissues of Gang geese. Eighty healthy male Gang geese were reared under the same feeding conditions, and were divided at 14 weeks of age into a control group and an overfed group. All birds were slaughtered after three weeks of over feeding. Gene expression and protein content of several genes involved in the mTOR pathway were evaluated. The results showed that the gene expression of mTOR, raptor, and rictor, and the protein contents of mTOR and PI3K were higher in liver, breast muscle, and leg muscle of the overfed group than that of control group. However, the S6K expression level was clearly lower in the liver of the overfed group than that of control group, and there was no evident difference in both breast muscle and leg muscle between the control group and the overfed group. These results suggest that overfeeding induces the activity of raptor, rictor, and mTOR, and that mTOR signaling pathway was closely linked with PI3K pathway in the evaluated geese.

Recently, with numerous environmental problems being caused by chemical fertilizer overuse, agricultural practices are shifting toward the development of environmentally friendly N fertilizers. In this study, pot and field experiments were simultaneously conducted to investigate the effect of poly(y-glutamic acid) (γ-PGA) on the yield, N use efficiency, and soil microenvironment of wheat. Our study demonstrates a statistically significant increase in winter wheat, number of tillers, seed number per spike, yield, soil microbial biomass N (SMBN), and soil enzymes after γ-PGA application. The highest grain yield of 7435.69 ± 55.91 kg ha-1 was obtained after γ-PGA application in the field experiment, which was 7.17% higher than the urea control. The N recovery efficiency increased by 11.81%-14.00% and 11.30%-11.38% after the application of γ-PGA in pot and field experiments, respectively. More mineral nitrogen in soil was immobilized by the microbes after γ-PGA application at the early growth stage of wheat. The immobilized nitrogen was gradually released at the late growth stage. The results demonstrate that γ-PGA can be used as a fertilizer synergist.

Channel adaptive M-ary quadrature amplitude modulation (M-QAM) schemes have been developed to provide higher average link spectral efficiency by taking advantage of the time-varying nature of wireless fading channels. Much of the earlier work on such schemes uses the assumption that thresholds designed for additive white Gaussian noise (AWGN) channels can be directly applied to slowly varying block-fading channels. The thresholds are calculated with a commonly used approximation bit error rate (BER) expression in these schemes. The first aim of this paper was to investigate the accuracy of using this common BER expression in a fading channel. This was done by comparing the result of the average BER expression derived using the approximate expression with results of simulations over a Nakagami-m block-fading channel. The second aim was to show that the inaccuracy in the threshold values determined using the closed form approximation expression would lead to inappropriate operation of the adaptive M-QAM scheme in a fading channel. This was done by comparing expected theoretical values with the simulation results. Two alternative approximate BER expressions for M-QAM in AWGN were then presented and used to determine the average M-QAM of BER over a Nakagami-m fading channel. The comparison between the average BER expressions and the simulation showed a much closer match. More accurate thresholds for the adaptive M-QAM system were then determined using one of the two average BER expressions and the accuracy of these threshold points was then verified using simulation results.

Repeat-punctured turbo codes, an extension of the conventional turbo-coding scheme, has shown a significant increase in bit-error rate performance at moderate to high signal-to-noise ratios for short frame lengths. Superorthogonal convolutional turbo codes (SCTC) makes use of superorthogonal signals to improve the performance of the conventional turbo codes and a coding scheme that applies the repeat-punctured technique into SCTC has shown to perform better. We investigated two new low-rate coding schemes, repeat-punctured superorthogonal convolutional turbo codes (RPSCTC) and dual-repeat-punctured superorthogonal convolutional turbo codes (DRPSCTC), that make use of superorthogonal signaling, together with repetition and puncturing, to improve the performance of SCTC for reliable and effective communications. Simulation results in the additive white Gaussian noise (AWGN) channel and the frequency non-selective Rayleigh fading channel are presented together with analytical bounds of bit error probabilities, derived from transfer function bounding techniques. From the simulation results and the analytical bounds presented, it is evident that RPSCTC and DRPSCTC offer a more superior performance than SCTC in the AWGN channel, as well as in flat Rayleigh non-line-of-sight fading channels. The distance spectrum is also presented for the new schemes and accounts for the performance improvement rendered in simulations. It is important to note that the improved performance that SCTC, and consequently RPSCTC and DRPSCTC, exhibit is achieved at the expense of bandwidth expansion and complexity and would be ideal for power-limited satellite communication links or interference-limited systems.