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In this paper, a new high-temperature superconducting (HTS)-based microwave radiometer with an improved sensitivity is presented. The cryogenic receiver front end consists of an HTS filter and a cryogenic low noise amplifier (LNA). The cryogenic receiver front end shows an ultra-low noise figure and can suppress radio frequency interference (RFI) effectively. The proposed HTS filter works at a center frequency of 1.4135 GHz with a bandwidth of 25 MHz. The measured mid-band insertion loss, side band steepness, and out-of-band attenuation of the HTS filter are 0.14 dB, 35 dB/MHz, and 80 dB, respectively. The noise figure of the cryogenic LNA is about 0.27 dB at a temperature of 77 K. Compared with other total power radiometers, the proposed radiometer has a lower receiver noise temperature, which can improve the sensitivity with a short integration time of the satellite-based salinity meter. In addition, since the bandwidth of the salinity meter is fixed and the integration time of satellite-based equipment is limited, such a low receiver noise temperature can increase the flexibility of future satellite payload configuration program. [ABSTRACT FROM AUTHOR]

Summary: Sustainable agricultural management practices improve soil processes, prevent soil erosion and consequently enhance crop productivity. The integrated agricultural practice (IP) developed in northeast China, by altering row spacing of planting, adopting no‐tillage and returning all crop residues, showed great benefit in sustaining crop yield. However, its effect on the soil microbiome remains largely elusive. This study evaluated the effect of 12‐year integrated agricultural practice on the structure and activity of the soil microbial community at different soil depths in China's Mollisols zone. The experiment consisted of integrated agricultural practice and conventional practice (CP) treatments in a split‐plot arrangement. The soil microbial community was characterized by MiSeq sequencing. The results showed that agricultural practices affected 12 phyla, 24 classes, 32 orders and 75 families in the bacterial community and one phyla, four classes, 12 orders and 18 families in the fungal community. Integrated agricultural practice resulted in greater bacterial richness and diversity, and increased the relative abundances of Actinobacteria, Gemmatimonadetes, Verrucomicrobia and Ascomycota, but reduced Bacteroidetes, Firmicutes and Basidiomycota in the dominant bacterial and fungal phyla. These findings suggested that integrated agricultural practice modified the soil physiochemical properties and consequently altered microbial community structure and diversity, which in turn affected soil microbial biomass and enzyme activities. These changes under integrated agricultural practice could have contributed to the enhanced crop yield, suggesting that IP is a sustainable agricultural practice. Highlights: How does soil microbial community change in the IP and CP soils? IP affected the soil microbial community and activity. Bacterial and fungal community structure correlated significantly with soil physiochemical properties. IP is a promising sustainable agricultural practice. [ABSTRACT FROM AUTHOR]

Superconducting microwave resonators are reliable circuits widely used for detection and as test devices for material research. A reliable determination of their external and internal quality factors is crucial for many modern applications, which either require fast measurements or operate in the single photon regime with small signal to noise ratios. Here, we use the circle fit technique with diameter correction and provide a step by step guide for implementing an algorithm for robust fitting and calibration of complex resonator scattering data in the presence of noise. The speedup and robustness of the analysis are achieved by employing an algebraic rather than an iterative fit technique for the resonance circle. [ABSTRACT FROM AUTHOR]

Nonlinear inductance of intrinsic Josephson junction arrays in Tl-2212 thin films has been investigated. Misaligned Tl-2212 thin films were fabricated on 20° vicinal LaA1O3 substrates and then patterned into long bridges by standard photolithography and wet chemical etching. Each bridge forms a large array of intrinsic Josephson junctions. We have measured the Josephson inductance of the bridges in the zero-DC-voltage state at 77 K and show that its dependence on the critical current is in a good agreement with theory. Also, we have numerically studied the nonlinearity of the Josephson inductance and present dependence of the distortion factor on the bias and AC signal currents. Based on the obtained results, we have designed a 10-pole narrow-band lumped-element filter with the tunable center frequency in the range from 1900 MHz to 1960 MHz. Simulations show that the filter has good selectivity. [ABSTRACT FROM AUTHOR]

The article reports that lead magnesium niobate-lead titanate (PMN-PT) has been widely investigated for its excellent dielectric and piezoelectric properties, which makes it an ideal material for applications in multiplayer ceramic capacitors, piezoelectric transducers and solid-state actuators. The pure perovskite PMN-PT powders can be obtained at the temperature of 750 degrees by the rutile precursor method. The phase formation and stability were measured by a simultaneous thermogravimetric analysis and differential thermal analysis.

Objective: To evaluate the value of p16 INK4a detected by p16 INK4a immunostaining as a new generation of cervical cytology for primary screening and secondary screening in population-based cervical cancer screening, and in improving cytological diagnosis. Methods: Between 2016 and 2018, 5 747 non-pregnant women aged 25-65 years with sexual history were recruited and underwent cervical cancer screening via high-risk (HR)-HPV/liquid-based cytological test (LCT) test in Shenzhen and surrounding areas. All slides were immuno-stained using p16 INK4a technology, among them, 902 cases were offered p16 INK4a detection during primary screening, and the remaining 4 845 cases were called-back by the virtue of abnormal HR-HPV and LCT results for p16 INK4a staining. Participants with complete LCT examination, HR-HPV test, p16 INK4a staining and histopathological examination results were included in this study. The performance of p16 INK4a in primary and secondary screening, and in assisting cytology to detect high grade squamous intraepithelial lesion [HSIL, including cervical intraepithelial neoplasia (CIN) Ⅱ or Ⅲ] or worse [HSIL (CIN Ⅱ) + or HSIL (CIN Ⅲ) + ] were analyzed. Results: (1) One-thousand and ninety-seven cases with complete data of p16 INK4a and histology were included. Pathological diagnosis: 995 cases of normal cervix, 37 cases of low grade squamous intraepithelial lesion (LSIL), 64 cases of HSIL and one case of cervical cancer were found. Among them, 65 cases of HSIL (CIN Ⅱ) + and 34 cases of HSIL (CIN Ⅲ) + were detected. The positive rate of p16 INK4a in HSIL (CIN Ⅱ) + was higher than that in CINⅠ or normal pathology (89.2% vs 10.2%; P <0.01). (2) p16 INK4a as primary screening for HSIL (CIN Ⅱ) + or HSIL (CIN Ⅲ) + was equally sensitive to primary HR-HPV screening (89.2% vs 95.4%, 94.1% vs 94.1%; P >0.05), but more specific than HR-HPV screening (89.8% vs 82.5%, 87.7% vs 80.2%; P <0.05). p16 INK4a was equally sensitive and similarly specific to cytology (≥LSIL; P >0.05). (3) The specificity of LCT adjunctive p16 INK4a for detecting HSIL (CIN Ⅱ) + or HSIL (CIN Ⅲ) + were higher than that of LCT alone or adjunctive HR-HPV ( P <0.01), while the sensitivity were similar ( P >0.05). (4) p16 INK4a staining as secondary screening: p16 INK4a was significantly more specific (94.1% vs 89.7%, 91.9% vs 87.4%; P <0.01) and comparably sensitive (84.6% vs 90.8%, 88.2% vs 91.2%; P >0.05) to cytology for triaging primary HR-HPV screening. HPV 16/18 to colposcopy and triage other HR-HPV with p16 INK4a was equally sensitive (88.2% vs 94.1%; P =0.500) and more specific (88.3% vs 83.0%; P <0.01) than HPV 16/18 to colposcopy and triage other HR-HPV with LCT≥ atypical squamous cells of undetermined significance (ASCUS), and the referral rate decreased (14.0% vs 19.4%; P =0.005). Conclusions: For primary screening, p16 INK4a is equally specific to cytology and equally sensitive to HR-HPV screening. p16 INK4a alone could be an efficient triage after primary HR-HPV screening. In addition, p16 INK4a immunostaining could be used as an ancillary tool to cervical cytological diagnosis, and improves its accuracy in cervical cancer screening.

Chemokines have been shown to play a critical role in tumor development and progression. However, little is known about the function and molecular mechanisms of CXCR6 in multiple malignancies. In the present study, we aimed to investigate the role of CXCR6 in human hepatocellular carcinoma (HCC). The expression of CXCR6 was examined by immunohistochemical assay using a tissue microarray procedure. A loss-of-function experiment was performed to explore the effects of lentivirus-mediated CXCR6 shRNA (shCXCR6) on cell proliferation and invasive potential by MTT and Transwell assays in HCC cell line (SMMC-7721). It was found that the expression of CXCR6 protein was significantly increased in HCC tissues compared with that in adjacent non-cancerous tissues (ANCT) (63.04&#x0025; vs 36.96&#x0025;, P=0.019), and correlated with the lymph-vascular space invasion in HCC patients (P=0.038). Knockdown of CXCR6 repressed cell proliferation and invasion of HCC cells followed by the down-regulation of vascular endothelial growth factor (VEGF). Taken together, our findings show that high expression of CXCR6 is positively associated with distant invasion of HCC patients, and blockade of CXCR6 signaling suppresses the growth and invasion of HCC cells through inhibition of the VEGF expression, suggesting that CXCR6 may represent a promising therapeutic target for the treatment of HCC.

Qinchuan is a red or yellow draft and beef breed in China. In order to identify a predictor of carcass traits on the basis of associations between carcass traits and gene polymorphism, variation in the bovine chemerin gene was investigated using PCR-single-strand conformational polymorphism and DNA sequencing. An SNP of A868G located in exon 2 of the Bos taurus chemerin gene was detected in 716 samples of six breeds (Jiaxian red, Luxi, Nan yang, Qinchuan, Simmental and Luxi crossbred steers, and Xia'nan), all in China, and three genotypes (AA, AG and GG) were found. Based on the χ(2) test, the AA/AG/GG genotype frequencies of all six breeds were found to be in Hardy-Weinberg equilibrium. A possible association of A868G with some carcass traits was investigated in 106 Qinchuan cattle. Animals with the AG genotype were found to have significantly lower mean loin eye area and meat tenderness compared to those with the AA and GG genotypes. However, there was no significant association between any individual haplotype and backfat thickness, water holding capacity or marbling score. We suggest that A868G could be used as a molecular marker in marker-assisted selection for carcass traits.

CCAAT/enhancer-binding protein alpha (C/EBPα) is an essential transcriptional factor regulating the differentiation of adipocytes. We report a novel single nucleotide polymorphism (C271A) of the C/EBPα gene in six indigenous Chinese cattle breeds using PCR-SSCP and DNA sequencing methods. Allele frequencies were investigated and evaluated by the χ(2) test in 817 individuals; all populations were found to be in Hardy-Weinberg equilibrium. Gene heterozygosity, effective allele numbers and polymorphism information content of the C/EBPα locus varied from 0.50 to 0.54, 1.84 to 1.99 and 0.35 to 0.37, respectively. We also evaluated a potential association of the C/EBPα SNP with ultrasound traits in 555 individuals; individuals of the AA genotype had greater ultrasound backfat thickness than did genotype CC (0.36 versus 0.34 cm, P < 0.01); genotypes AA and CA had higher ultrasound marbling scores than did genotype CC (3.53, 3.52 versus 3.37, P < 0.05). Analysis based on meat quality data in another 204 Qinchuan cattle showed that animals with genotype AA had bigger loin eye areas than did genotype CA (87.10 versus 79.08 cm(2), P < 0.05). These results indicate that the C271A SNP of the C/EBPα gene could be used as a molecular marker for selecting beef cattle with superior carcass traits.