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A design method of BJTs for high-precision temperature-sensing is studied. The effects of non-idealities in the BJT on temperature-sensing accuracy are analyzed, and an accuracy evaluation formula containing the non-idealities is derived. We have proposed a novel parameter criteria of high-precision temperature-sensing BJT which constrains the influenced error of each non-ideality below ±0.1 °C using the variable-controlling procedure. The conversion approach from the proposed parameter criteria to electrical characteristics is also developed to guide the high-precision temperature-sensing BJT design. According to the proposed method, temperature-sensing BJTs are designed and fabricated. The test results showed that the temperature-sensing accuracy is within ±0.5 °C in temperature range of −55 °C to 125 °C, which meets the need for high-precision temperature sensing. [ABSTRACT FROM AUTHOR]

Avian pathogenic Escherichia coli (APEC) causes a variety of extraintestinal diseases known as colibacillosis and is responsible for significant economic losses in the poultry industry worldwide. Biofilm formation results in increased morbidity and persistent infections, and is the main reason for the difficult treatment of colibacillosis with antimicrobial agents. It is reported that the transcriptional regulator McbR regulates biofilm formation and mucoidy by repressing the expression of the periplasmic protein YbiM, and activates the transcription of the yciGFE operon by binding to the yciG promoter in E. coli K-12. However, whether McbR regulates biofilm formation and H2O2 stress response in APEC has been not reported. The present study showed that, in the clinical isolate APECX40, the deletion of mcbR increased biofilm formation by upregulating the transcription of the biofilm-associated genes bcsA, fliC, wcaF , and fimA. In addition, the deletion of mcbR decreased H2O2 stress response by downregulating the transcript levels of the stress-associated genes yciF and yciE. The electrophoretic mobility shift assays confirmed that McbR directly binds to the promoter regions of yciG and yciF. This study may provide new clues to understanding gene regulation in APEC. [ABSTRACT FROM AUTHOR]

Pancreatic intraepithelial neoplasia (PanIN) is the most common precursor lesion of pancreatic ductal adenocarcinoma (PDAC), which is a highly malignant tumor and lack of effective treatment. Although Xiao Chai Hu Tang (XCHT) has a good therapeutic effect on pancreatic cancer patients with advanced stage, the effect and mechanism of XCHT remains unclear in pancreatic tumorigenesis. To assess the therapeutic effects of XCHT on the malignant transformation from PanIN to PDAC and to reveal its mechanisms of pancreatic tumorigenesis. Syrian golden hamster were induced by N-Nitrosobis (2-oxopropyl) amine (BOP) to establish the pancreatic tumorigenesis model. The morphological changes of pancreatic tissue were observed by H&E and Masson staining; the Gene ontology (GO) analysis the transcriptional profiling changes; the mitochondrial ATP generation, mitochondrial redox status, mitochondrial DNA (mtDNA) N6-methyladenine (6mA) level and relative mtDNA genes expressions were examined. In addition, immunofluorescence detect the cell localization of 6mA in human pancreatic cancer PANC1 cell. Using the TCGA database, the prognostic effect of mtDNA 6mA demethylation ALKBH1 expression on pancreatic cancer patients was analyzed. We confirmed the mtDNA 6mA levels were gradually increased with the mitochondrial dysfunction in PanINs progression. XCHT showed the effect to inhibit the occurrence and development of pancreatic cancer in Syrian hamster pancreatic tumorigenesis model. In addition, the lack of ALKBH1 mediated mtDNA 6mA increase, mtDNA coded genes down-expression and abnormal redox status were rescued by XCHT. ALKBH1/mtDNA 6mA mediated mitochondrial dysfunction to induce the occurrence and progression of pancreatic cancer. XCHT can improve ALKBH1 expression and mtDNA 6mA level, regulate the oxidative stress and expression of mtDNA coded genes. This study investigated a new molecular mechanism of pancreatic tumorigenesis, and revealed the therapeutic efficacy of XCHT in pancreatic tumorigenesis for the first time. [Display omitted] [ABSTRACT FROM AUTHOR]

Extended-spectrum β-lactamase-positive Escherichia coli is an important causative agent of mastitis in dairy cows that results in reduced milk production and quality, and is responsible for severe economic losses in the dairy industry worldwide. The quorum sensing signaling molecule autoinducer 2 (AI-2) is produced by many species of gram-negative and gram-positive bacteria, and might be a universal language for intraspecies and interspecies communication. Our previous work confirmed that exogenous AI-2 increases the antibiotic resistance of extended-spectrum β-lactamase-positive E. coli to the β-lactam group of antibiotics by upregulating the expression of the TEM-type β-lactamase. In addition, this regulation relies on the function of the intracellular AI-2 receptor LsrR. In the present work, we reported that exogenous imidazole, a furan carbocyclic analog of AI-2, decreases the antibiotic resistance of a clinical E. coli strain to β-lactam antibiotics by inhibiting the function of AI-2. [ABSTRACT FROM AUTHOR]

• The Cuonadong Be-W-Sn skarn deposit in Tibet is newly discovered and belongs to a new type of deposits for exploration. • The hosting rocks were emplaced at 18 Ma and contains older xenolithic zircon grains with ages of 490 Ma and 711 Ma. • Strong water-rock interaction was favorable for the formation of scheelite. • Highly differentiated nature of magmas was necessary for the enrichment of Be and REEs. The Himalayan orogenic belt is characterized by widespread leucogranites, which are mostly peraluminous with less than 5% mafic minerals. Previous studies mainly focused on the petrological characteristic, genetic mechanism, magmatic evolution and tectonic significance of these leucogranites. However, recently, a skarn-type Be–W–Sn polymetallic deposit, which is spatially related to the Cuonadong leucogranites of the Himalayan leucogranites belt, was discovered. The orebodies occur in the inner and outer contact zones between the Cuonadong leucogranites and their surrounding marble. This study focuses on the the characteristics of the skarn mineral assemblages. The deposit shows a typical skarn mineral zonation, from inside to outside, including dark pyroxene-garnet skarn zone, red garnet zone, dark green amphibole-specularite zone, light-green vesuvianite-epidote ribbon, and vesuvianite-chlorite zone. Zircon U-Pb dating shows that the ore-related leucogranite was emplaced at ca. 18 Ma. Geochemically, the leucogranite has high SiO 2 , Al 2 O 3 , Na 2 O, K 2 O and low CaO contents belonging to peraluminous granite. The Cuonadong leucogranite is characterized by right-dipping chondrite-normalized REE patterns with distinct negative Eu anomalies. Importantly, all samples show Lanthanide tetrad effect on chondrite-normalized REE patterns, indicating significant melt-fluid interaction has occurred due to strong fractional crystallization. Additionally, the Cuonadong leucogranite is enriched in large ion lithophile elements (such as Rb) and relatively depleted in high field strength elements (such as Nb, Zr, Hf), suggesting a crustal source region. High F and B contents in the magma could have significantly increased the solubility of water in the magma, while the magmatic-hydrothermal solution enriched in F and B should have remarkably enhanced the metal-carrying capacity and increased the permeability of surrounding rocks, which in turn effectively facilitated water–rock reaction. [ABSTRACT FROM AUTHOR]

• Late Cretaceous intrusions in the Yidun Arc emplaced gradually from north to south. • The different types of deposits were probably controlled by the magma sources. • The Late Cretaceous granites were formed in a regional extensional setting. The Yidun Arc is an important tectonic unit and polymetallic metallogenic belt in the Sanjiang tectono-magmatic belt, in which many Cretaceous (138–75 Ma) granites and associated polymetallic deposits are distributed along a NW-trending belt. The Queershan, Cuomolong, Rongyicuo, and Genie granitic intrusions and the associated Sn–Pb–Zn–Ag polymetallic deposits are distributed in the Changtai and Xiangcheng Arcs, whereas the Xiuwacu, Relin, Hongshan, and Tongchanggou granitic intrusions and the associated Cu–Mo–W deposits are mainly distributed in the Geza Arc. This study presents new zircon U–Pb–Hf–O isotopic data for the Queershan, Cuomolong, Rongyicuo, Genie, Xiuwacu, and Tongchanggou granitic intrusions, combined with the structural analysis of the Xiuwacu granitic complex, to discuss the differences in the petrogenesis and metallogenesis of these granitic intrusions, as well as the geodynamic processes that controlled the formation of the Late Cretaceous intrusions and related deposits. Hf-O isotopic characteristics indicate that the highly fractionated granites (HFG) in the Changtai and Xiangcheng Arcs were mainly derived from the partial melting of metasedimentary crustal materials with a minor input from mantle components, while the I-type granites (IG) in the Geza Arc were predominantly derived from the partial melting of ancient lower crustal material. The spatial distributions of the different types of deposits in the Yidun Arc were probably controlled by the magma sources. Reduced magmas produced by the partial melting of the sedimentary crust in the Changtai and Xiangcheng Arcs are favorable for W, Sn, Pb, and Zn mineralization, whereas oxidized magmas produced by the partial melting of the lower crust in the Geza Arc are conducive to the enrichment of Cu, Au, and Mo. The geochronological data indicate that the emplacement ages of the Late Cretaceous granites in the Yidun Arc gradually decrease from north to south (ranging from 106 to 73 Ma), reflecting the southward lateral tectonic migration. The structural analysis of the Xiuwacu W–Mo deposit, in combination with previous studies, demonstrated that the Late Cretaceous granites in the Yidun Arc were likely formed in a regional extensional setting, which was probably related to the slab break-off of the Bangong–Nujiang oceanic slab or the subduction of the Yarlung Zangbo oceanic slab. [ABSTRACT FROM AUTHOR]

• Sulfur of the Larong W-Mo deposit is of magmatic origin. • In-situ trace elemental and Pb isotopic compositions indicate a crustal origin. • Fluid-rock interaction might be the key factor resulting in the W-Mo mineralization. • Three stages of W-polymetallic metallogenic events have been identified in the BNMB. The Late Cretaceous (ca. 92 Ma) Larong porphyry W-Mo deposit (39.44 Mt WO 3 @ 0.1541%), a newly discovered deposit in the easternmost Bangong-Nujiang metallogenic belt (BNMB), is located in eastern Tibet. The W-Mo mineralization occurs as veins and stock-works hosted in monzogranite porphyry, granodiorite porphyry and surrounding quartz schist, and can be divided into two main paragenetic stages: the W-mineralization stage (Stage I) consists of various K-feldspar-quartz-scheelite veins and the quartz-sulfide stage (Stage II) is dominated by molybdenite and pyrite, of which the latter can be further subdivided into three sub-stages. Here, we present LA-ICPMS in-situ trace elements and S-Pb isotopes of sulfides from the Larong deposit, in order to constrain the sources of ore-forming elements and the processes of mineralization. Our study shows that pyrite is rich in Co and As, molybdenite is rich in W, Pb and Bi, and chalcopyrite has high Sn contents. These results are consistent with the mineralization characteristics of the Larong deposit, where the main metallogenic elements are W and Mo, accompanied by Bi, Sn and Cu. Overall, sulfides from the Larong deposit have calculated δ34S VCDT values ranging from 0.25‰ to 6.37‰, suggesting a predominantly magmatic origin for sulfur. From Stage II-1, to Stage II-2, to Stage II-3, the average δ34S VCDT values of pyrite change from 0.33‰, to 1.88‰, to 5.34‰, showing a progressive and gradual change in redox and temperature conditions. Molybdenite has high Pb isotopic ratios (208Pb/204Pb = 39.356–39.908, 207Pb/204Pb = 15.747–15.928, 206Pb/204Pb = 18.843–20.120) but low Re contents, and pyrite has low Ni contents, implying that the ore-forming materials were mainly derived from the crust. We propose that the W-Mo mineralization is genetically related to the Late Cretaceous monzogranite porphyry, with the mineralization of W and Mo occurring as a result of decreases in temperature and oxygen fugacity of the ore-forming fluid exsolved from the magma. In combination with previous studies, our study led to the identification of three W-dominated polymetallic metallogenic events and mineralization potential of igneous rocks in the BNMB. [ABSTRACT FROM AUTHOR]

• The mineralization event at the Bengge gold deposit occurred during the Cretaceous. • The ore bodies are closely related to phyllic alteration and the Bengge deposit is an intrusion-related gold deposit. • Ore fluids with significant portion of magmatic waters were derived from deep unexposed intrusions during the Cretaceous. • A Cretaceous gold mineralization event occurred in the Zhongdian–Muli region. The Bengge gold deposit is one of a small number of deposits in the Zhongdian-Muli region, which is part of the southern segment of the Yidun Terrane in the eastern Tibetan Plateau. The deposit is hosted in a Late Triassic alkaline igneous complex comprising mainly biotite–pyroxene syenite and quartz syenite, emplaced into Triassic slate. These syenites show phyllic alteration with mineral association of quartz–sericite–pyrite–carbonate. The main gold mineralization occurs in fault zones as gold–sulfide–quartz veins, in altered syenite as telluride in veinlets, and as fissure-filling gold in disseminated pyrite. Four stages of veins are recognized: sheeted K-feldspar–quartz–magnetite veins (dikes) (stage I), quartz–carbonate–K-feldspar veins with sericite–quartz–pyrite alteration haloes (stage II), polymetallic sulfide–telluride–sericite–quartz veins with pervasive phyllic alteration (stage III), and quartz–carbonate–stibnite veins (stage Ⅳ). The stage II and III veins are closely related to gold mineralization. 40Ar/39Ar dating of hydrothermal sericites from the phyllic alteration zone, which are intergrown with gold-bearing pyrite and telluride, yielded an age of ~126 Ma, indicating the mineralization event occurred in the Cretaceous extensional setting. Raman spectroscopy and microthermometry study for fluid inclusions in quartz from stage II revealed heterogeneous trapping of low-salinity (0.14–6.63 wt% NaCl equivalent) and mesothermal (270–300 °C) CO 2 –H 2 O–NaCl ore-forming hydrothermal fluids. The calculated fluid-trapping pressures range mainly from 750 to 850 bar. δ18O values of quartz from the gold mineralization stage (stage II) vary between 15.21‰ and 19.35‰. The δ18O values for waters in equilibrium with quartz vary from 6.96‰ to 10.73‰, which are consistent with values for magmatic waters. We propose that the auriferous fluids were derived from an underlying intrusion during the Cretaceous. The geological characteristics, low salinity, and mesothermal CO 2 –H 2 O–NaCl fluids, and the magmatic source of the ore-forming fluids, all support the hypothesis that the Bengge deposit is an intrusion-related gold deposit. [ABSTRACT FROM AUTHOR]

Background and Aims Although preconditioning of sphingosine 1-phosphate (S1P) has been shown to protect myocytes from hypoxia reoxgenation injury in vitro , the role of S1P postconditioning on myocardial ischemia reperfusion injury (MIRI) in vivo and its related mechanism are unknown. The aim of this study was to investigate the protective role of sphingosine 1-phosphate (S1P) postconditioning in MIRI via its effects on mitochondrial signaling and Akt/Gsk3β phosphorylation. Methods Rats were subjected to MIRI, consisting of 30 min of ischemia followed by 120 min of reperfusion, with S1P administered at the beginning of the reperfusion. Myocardial infarct size and apoptotic index were measured by triphenyltetrazolium (TTC) and terminal deoxynucleotide transferase dUTP nick-end labeling (TUNEL) assays, respectively. Akt and Gsk3β phosphorylation, caspase-3 cleavage, and cytochrome c translocation were assessed by western blot. Mitochondrial permeability transition pore (MPTP) opening and mitochondrial membrane potential (MMP, ΔΨ) were also examined to determine overall mitochondrial function. Results S1P postconditioning significantly decreased myocardial infarct size and apoptosis, as well as enhanced Akt and Gsk3β phosphorylation, attenuated caspase-3 cleavage and cytosolic cytochrome c translocation, and inhibited MPTP opening, which subsequently preserved Δψ. Electron microscopy also confirmed that S1P helped maintain myocardial mitochondria integrity. Moreover, the protective effects of S1P treatment were blocked by cotreatment with a PI3K inhibitor, LY294002. Conclusions These results suggest that S1P postconditioning protects against MIRI by regulating mitochondrial signaling and Akt/Gsk3β phosphorylation. [ABSTRACT FROM AUTHOR]

Abstract: Principal component analysis (PCA) is frequently used in geosciences for information extraction. In many applications, masking PCA has been used to create subsets of samples or sub-areas to enhance the effect of the main objects of interest. In this paper we suggest how the representativeness of samples or pixels can be quantified using a fuzzy membership function based on fuzzy set theory. In this new method, the relative importance of pixels or samples can be taken into account using a multivariate statistical method such as PCA. A Fuzzy Masking PCA is proposed and implemented in GeoDAS GIS on the basis of a spatially weighted PCA (SWPCA). This paper introduces the mathematical treatment of the fuzzy masking PCA and follows a case study of identifying the locations of intrusive bodies from geochemical data in the Gejiu mineral district in Yunnan, China. Power-law functions based on the inverse distance from mapped felsic intrusions are applied as weighting functions in FMPCA. The results indicate that fuzzy mask PCA increases the signal-noise ratio of the component representing igneous intrusions and decreases the influence of sedimentary rocks. The areas delineated as potential areas for new intrusions (including buried intrusions) are valuable guides for Sn mineral prospecting. [Copyright &y& Elsevier]

Abstract: Corresponding lattice planes of 4:5 Si-to-SiC atomic matching structures are observed at the Si(111)/6H-SiC(001) interface. The periodical Si/SiC interface structure is further illustrated and characterized by an atomic model derived from experiment results. It is discovered that there is a minor lattice mismatch of 0.26% in the structure. Moreover, the atomic structure of the interface and its stability are energetically investigated by molecular dynamics simulations. The results demonstrate that the atomic relaxations caused by lattice mismatch are slight to the growth of a perfect crystalline Si film and the interfaces are quite stable with the formation energy of −22.452eV. [Copyright &y& Elsevier]