Analysis on GNSS receiver with the principles of signal and information

In the paper, principles of signal and information were introduced to the design of GNSS receiver. Analyze Antenna and radio frequency (RF) front-end with the perspective of transmission link, Understand the baseband processing though signal modulate and demodulate, design the navigation calculation utilized the information pick-up and disposal, and research the receiver system by the inherent connection between signal and information. New ways and means would be developed though these researches. © (2013) Trans Tech Publications, Switzerland

Molecular cloning and characterization of a novel expressed sequence tag (EST) associated with fecundity in goats

To screen the genes controlling the fecundity traits in goats, a DDRT-PCR technique was applied. We found a new EST which highly expressed in Chinese native prolific goat breed, Haimen goats. There exists a difference of EST expression level between the prolific and non-prolific goat breed, indicating EST might associate to fecundity in goats. A full-length cDNA with 2253 base pairs was obtained by the 3’- and 5’-RACE method based on the EST sequence encoding a protein segment of 201 amino acid residues. Tissue specific distribution and sequence analysis implicated the likely involvement of EST in the regulation of the hormones related to fecundity

Metal–Organic Framework Decorated Cuprous Oxide Nanowires for Long-lived Charges Applied in Selective Photocatalytic CO₂ Reduction to CH₄

Improving the stability of cuprous oxide (Cu2O) is imperative to its practical applications in artificial photosynthesis. In this work, Cu2O nanowires are encapsulated by metal–organic frameworks (MOFs) of Cu3(BTC)2 (BTC=1,3,5-benzene tricarboxylate) using a surfactant-free method. Such MOFs not only suppress the water vapor-induced corrosion of Cu2O but also facilitate charge separation and CO2 uptake, thus resulting in a nanocomposite representing 1.9 times improved activity and stability for selective photocatalytic CO2 reduction into CH4 under mild reaction conditions. Furthermore, direct transfer of photogenerated electrons from the conduction band of Cu2O to the LUMO level of non-excited Cu3(BTC)2 has been evidenced by time-resolved photoluminescence. This work proposes an effective strategy for CO2 conversion by a synergy of charge separation and CO2 adsorption, leading to the enhanced photocatalytic reaction when MOFs are integrated with metal oxide photocatalyst

MicroRNA-375 inhibits tumour growth and metastasis in oesophageal squamous cell carcinoma through repressing insulin-like growth factor 1 receptor

Background: To understand the involvement of micro- RNA (miRNA) in the development and progression of oesophageal squamous cell carcinoma (ESCC), miRNA profiles were compared between tumour and corresponding non-tumour tissues. Methods: miRCURY LNA array was used to generate miRNA expressing profile. Real-time quantitative PCR was applied to detectthe expression of miR-375 in ESCC samples and its correlation with insulin-like growth factor 1 receptor (IGF1R). Methylation-specific PCR was used to study the methylation status in the promoter region of miR-375. The tumour-suppressive effect of miR-375 was determined by both in-vitro and in-vivo assays. Results: The downregulation of miR-375 was frequently detected in primary ESCC, which was significantly correlated with advanced stage (p=0.003), distant metastasis (p<0.0001), poor overall survival (p=0.048) and disease-free survival (p=0.0006). Promoter methylation of miR-375 was detected in 26 of 45 (57.8%) ESCC specimens. Functional assays demonstrated that miR-375 could inhibit clonogenicity, cell motility, cell proliferation, tumour formation and metastasis in mice. Further study showed that miR-375 could interact with the 39-untranslated region of IGF1R and downregulate its expression. In clinical specimens, the expression of IGF1R was also negatively correlated with miR-375 expression (p=0.008). Conclusions: This study demonstrates that miR-375 has a strong tumour-suppressive effect through inhibiting the expression of IGF1R. The downregulation of miR-375, which is mainly caused by promoter methylation, is one of the molecular mechanisms involved in the development and progression of ESCC.published_or_final_versio

Broadband High-Efficiency Power Amplifier with Quasi-Elliptic Low-Pass Response

© 2013 IEEE. This paper presents a broadband high-efficiency harmonic-tuned power amplifier (PA) with quasi-elliptic low-pass responses. A combination of continuous Class-F-1 and extended continuous Class-F PA modes is employed to significantly expand the design space. A quasi-elliptic low-pass matching network is proposed, which can realize a broadband impedance matching in the predefined optimal impedance region desired by the combination of PA modes. Furthermore, two transmission zeros are generated near the passband, exhibiting high skirt selectivity and providing rapid impedance transition from the passband to the stopband. A wide stopband covering up to the third harmonic is achieved which shows good harmonic suppression. Design procedures of the proposed broadband PA are presented. To verify the proposed methodology, the broadband PA is fabricated and measured. The implemented PA achieves a bandwidth of 145.2% from 0.5 to 3.15 GHz. Over this frequency range, the drain efficiency is measured as 58-74.9% with the output power of greater than 39.03 dBm and a large signal gain ranging from 8.43 to 15.67 dB. A wide stopband is realized from 3.4 to 10 GHz, showing excellent quasi-elliptic low-pass responses. The measured adjacent leakage ratios (ACLRs) using a 20-MHz LTE signal with digital pre-distortion are below -45.06 dBc

Recent progress in organic-based radiative cooling materials: fabrication methods and thermal management properties

Organic-based materials capable of radiative cooling have attracted widespread interest in recent years due to their ease of engineering and good adaptability to different application scenarios. As a cooling material for walls, clothing, and electronic devices, these materials can reduce the energy consumption load of air conditioning, improve thermal comfort, and reduce carbon emissions. In this paper, an overview is given of the current fabrication strategies of organic-based radiative cooling materials, and of their properties. The methods and joint thermal management strategies including evaporative cooling, phase-change materials, fluorescence, and light-absorbing materials that have been demonstrated in conjunction with a radiative cooling function are also discussed. This review provides a comprehensive overview of organic-based radiative cooling, exemplifying the emerging application directions in this field and highlighting promising future research directions in the field

Autotaxin signaling facilitates β cell dedifferentiation and dysfunction induced by Sirtuin 3 deficiency

OBJECTIVE: β cell dedifferentiation may underlie the reversible reduction in pancreatic β cell mass and function in type 2 diabetes (T2D). We previously reported that β cell-specific Sirt3 knockout (Sirt3f/f;Cre/+) mice developed impaired glucose tolerance and glucose-stimulated insulin secretion after feeding with high fat diet (HFD). RNA sequencing showed that Sirt3-deficient islets had enhanced expression of Enpp2 (Autotaxin, or ATX), a secreted lysophospholipase which produces lysophosphatidic acid (LPA). Here, we hypothesized that activation of the ATX/LPA pathway contributed to pancreatic β cell dedifferentiation in Sirt3-deficient β cells. METHODS: We applied LPA, or lysophosphatidylcoline (LPC), the substrate of ATX for producing LPA, to MIN6 cell line and mouse islets with altered Sirt3 expression to investigate the effect of LPA on β cell dedifferentiation and its underlying mechanisms. To examine the pathological effects of ATX/LPA pathway, we injected the β cell selective adeno-associated virus (AAV-Atx-shRNA) or negative control AAV-scramble in Sirt3f/f and Sirt3f/f;Cre/+ mice followed by 6-week of HFD feeding. RESULTS: In Sirt3f/f;Cre/+ mouse islets and Sirt3 knockdown MIN6 cells, ATX upregulation led to increased LPC with increased production of LPA. The latter not only induced reversible dedifferentiation in MIN6 cells and mouse islets, but also reduced glucose-stimulated insulin secretion from islets. In MIN6 cells, LPA induced phosphorylation of JNK/p38 MAPK which was accompanied by β cell dedifferentiation. The latter was suppressed by inhibitors of LPA receptor, JNK, and p38 MAPK. Importantly, inhibiting ATX in vivo improved insulin secretion and reduced β cell dedifferentiation in HFD-fed Sirt3f/f;Cre/+ mice. CONCLUSIONS: Sirt3 prevents β cell dedifferentiation by inhibiting ATX expression and upregulation of LPA. These findings support a long-range signaling effect of Sirt3 which modulates the ATX-LPA pathway to reverse β cell dysfunction associated with glucolipotoxicity

Wnt2 secreted by tumour fibroblasts promotes tumour progression in oesophageal cancer by activation of the Wnt/β-catenin signalling pathway

Objectives: Interaction between neoplastic and stromal cells plays an important role in tumour progression. It was recently found that WNT2 was frequently overexpressed in fibroblasts isolated from tumour tissue tumour fibroblasts (TF) compared with fibroblasts from non-tumour tissue normal fibroblasts in oesophageal squamous cell carcinoma (OSCC). This study aimed to investigate the effect of TF-secreted Wnt2 in OSCC development via the tumour - stroma interaction. Methods: Quantitative PCR, western blotting, immunohistochemistry and immunofluorescence were used to study the expression pattern of Wnt2 and its effect on the Wnt/β-catenin pathway. A Wnt2-secreting system was established in Chinese hamster ovary cells and its conditioned medium was used to study the role of Wnt2 in cell proliferation and invasion. Results: Expression of Wnt2 could only be detected in TF but not in OSCC cancer cell lines. In OSCC tissues, Wnt2 (+) cells were mainly detected in the boundary between stroma and tumour tissue or scattered within tumour tissue. In this study, Wnt2-positive OSCC was defined when five or more Wnt2(+) cells were observed in 2003X microscopy field. Interestingly, Wnt2-positive OSCC (22/51 cases) was significantly associated with lymph node metastases (p=0.001), advanced TNM stage (p=0.001) and disease-specific survival (p<0.0001). Functional study demonstrated that secreted Wnt2 could promote oesophageal cancer cell growth by activating the Wnt/β-catenin signalling pathway and subsequently upregulated cyclin D1 and c-myc expression. Further study found that Wnt2 could enhance cell motility and invasiveness by inducing epithelial-mesenchymal transition. Conclusions: TF-secreted Wnt2 acts as a growth and invasion-promoting factor through activating the canonical Wnt/β-catenin signalling pathway in oesophageal cancer cells.published_or_final_versio

A Novel Strategy to Screen Bacillus Calmette-Guérin Protein Antigen Recognized by γδ TCR

BACKGROUND: Phosphoantigen was originally identified as the main γδ TCR-recognized antigen that could activate γδ T cells to promote immune protection against mycobacterial infection. However, new evidence shows that the γδ T cells activated by phosphoantigen can only provide partial immune protection against mycobacterial infection. In contrast, whole lysates of Mycobacterium could activate immune protection more potently, implying that other γδ TCR-recognized antigens that elicit protective immune responses. To date, only a few distinct mycobacterial antigens recognized by the γδ TCR have been characterized. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we established a new approach to screen epitopes or protein antigens recognized by the γδ TCR using Bacillus Calmette-Guérin- (BCG-) specific γ TCR transfected cells as probes to pan a 12-mer random-peptide phage-displayed library. Through binding assays and functional analysis, we identified a peptide (BP3) that not only binds to the BCG-specific γδ TCR but also effectively activates γδ T cells isolated from human subjects inoculated with BCG. Importantly, the γδ T cells activated by peptide BP3 had a cytotoxic effect on THP-1 cells infected with BCG. Moreover, the oxidative stress response regulatory protein (OXYS), a BCG protein that matches perfectly with peptide BP3 according to bioinformatics analysis, was confirmed as a ligand for the γδ TCR and was found to activate γδ T cells from human subjects inoculated with BCG. CONCLUSIONS/SIGNIFICANCE: In conclusion, our study provides a novel strategy to identify epitopes or protein antigens for the γδ TCR, and provides a potential means to screen mycobacterial vaccines or candidates for adjuvant

The wheat ω-gliadin genes: structure and EST analysis

A survey and analysis is made of all available ω-gliadin DNA sequences including ω-gliadin genes within a large genomic clone, previously reported gene sequences, and ESTs identified from the large wheat EST collection. A contiguous portion of the Gli-B3 locus is shown to contain two apparently active ω-gliadin genes, two pseudogenes, and four fragments of the 3′ portion of ω-gliadin sequences. Comparison of ω-gliadin sequences allows a phylogenetic picture of their relationships and genomes of origin. Results show three groupings of ω-gliadin active gene sequences assigned to each of the three hexaploid wheat genomes, and a fourth group thus far consisting of pseudogenes assigned to the A-genome. Analysis of ω-gliadin ESTs allows reconstruction of two full-length model sequences encoding the AREL- and ARQL-type proteins from the Gli-A3 and Gli-D3 loci, respectively. There is no DNA evidence of multiple active genes from these two loci. In contrast, ESTs allow identification of at least three to four distinct active genes at the Gli-B3 locus of some cultivars. Additional results include more information on the position of cysteines in some ω-gliadin genes and discussion of problems in studying the ω-gliadin gene family