Discovery of an Enormous Ly<i>α</i>Nebula in a Massive Galaxy Overdensity at<i>z</i>= 2.3

Cai, Zheng,Fan, Xiaohui,Yang, Yujin,Bian, Fuyan,Prochaska, J. Xavier,Zabludoff, Ann,McGreer, Ian,Zheng, Zhen-Ya,Green, Richard,Cantalupo, Sebastiano,Frye, Brenda,Hamden, Erika,Jiang, Linhua,Kashikawa, American Astronomical Society 2017 The Astrophysical journal Vol.837 No.1

<P>Enormous Ly alpha nebulae (ELANe), unique tracers of galaxy density peaks, are predicted to lie at the nodes and intersections of cosmic filamentary structures. Previous successful searches for ELANe have focused on wide-field narrowband surveys or have targeted known sources such as ultraluminous quasi-stellar objects (QSOs) or radio galaxies. Utilizing groups of coherently strong Ly alpha absorptions, we have developed a new method to identify high-redshift galaxy overdensities and have identified an extremely massive overdensity, BOSS1441, at z = 2-3. In its density peak, we discover an ELAN that is associated with a relatively faint continuum. To date, this object has the highest diffuse Ly alpha nebular luminosity of L-nebula = 5.1 +/- 0.1 x 10(44) erg s(-1). Above the 2 sigma surface brightness limit of SBLy alpha = 4.8 x 10(-18) erg s(-1) cm(-2) arcsec(-2), this nebula has an end-to-end spatial extent of 442 kpc. This radio-quiet source also has extended C IV lambda 1549 and He II lambda 1640 emission on greater than or similar to 30 kpc scales. Note that the Ly alpha, He II, and C IV emissions all have double-peaked line profiles. Each velocity component has an FWHM of approximate to 700-1000 km s(-1). We argue that this Lya nebula could be powered by shocks due to an active galactic nucleus-driven outflow or photoionization by a strongly obscured source.</P>

Mapping the Most Massive Overdensities through Hydrogen (MAMMOTH). II. Discovery of the Extremely Massive Overdensity BOSS1441 at<i>z</i>= 2.32

Cai, Zheng,Fan, Xiaohui,Bian, Fuyan,Zabludoff, Ann,Yang, Yujin,Prochaska, J. Xavier,McGreer, Ian,Zheng, Zhen-Ya,Kashikawa, Nobunari,Wang, Ran,Frye, Brenda,Green, Richard,Jiang, Linhua American Astronomical Society 2017 The Astrophysical journal Vol.839 No.2

<P>Cosmological simulations suggest a strong correlation between high optical-depth Lya absorbers, which arise from the intergalactic medium, and 3D mass overdensities on scales of 10-30 h(-1) comoving Mpc. By examining the absorption spectra of similar to 80,000 QSO sight lines over a volume of 0.1 Gpc(3) in the Sloan Digital Sky Survey III (SDSS-III), we have identified an extreme overdensity, BOSS1441, which contains a rare group of strong Lya absorbers at z = 2.32 +/- 0.02. This absorber group is associated with six QSOs at the same redshift on a 30 comoving Mpc scale. Using Mayall/MOSAIC narrowband and broadband imaging, we detect Lya emitters (LAEs) down to 0.7 x L-Ly alpha ' * a and reveal a large-scale structure of LAEs in this field. Our follow-up LBT observations have spectroscopically confirmed 20 galaxies in the density peak. We show that BOSS1441 has an LAE overdensity of 10.8 +/- 2.6 on a 15 comoving Mpc scale, which could collapse to a massive cluster with M greater than or similar to 10(15) M-circle dot at z similar to 0. This overdensity is among the most massive large-scale structures at z similar to 2 discovered to date.</P>

A Nine-level ANPC/H-Bridge Inverter for Open-Winding Motor Drive System

Xiaohui Xu,Kui Wang,Nianzhou Liu,Zedong Zheng,Yongdong Li 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

In order to increase the output power and voltage levels, a nine-level ANPC/H-Bridge inverter for high power medium voltage motor drive applications is presented in this paper. Each phase of this inverter consists of two fivelevel ANPC bridges and all the phases are powered by a common DC-link, which is very suitable for ship integrated electric propulsion with open-winding multi-phase motors. A hybrid modulation method is adopted to control this inverter. The series connected or high-voltage switches in all the fivelevel ANPC bridges are operated at fundamental frequency and the other switches are controlled with PS-PWM, which is easy to implement and can achieve the natural voltage balance of the neutral-point potential and flying capacitor voltages. A capacitor voltage balancing method based on this hybrid modulation method is also proposed. Simulation and experimental results are presented to verify the validity of this method.

Inactivation of epithelial sodium ion channel molecules serves as effective diagnostic biomarkers in clear cell renal cell carcinoma

Zheng Qian,Wang Yifang,Zhao Ran,Han Peipei,Zhao Jun,Li Limei,Zhou Xiaohui,Li Ping,Mo Yingxi,Pan Xinli,Luo Wenqi,Zhou Xiaoying 한국유전학회 2023 Genes & Genomics Vol.45 No.7

Background Non-voltage-gated sodium channel, also known as the epithelial sodium channel (ENaC), formed by heteromeric complexes consisting of SCNN1A, SCNN1B, and SCNN1G, is responsible for maintaining sodium ion and body fluid homeostasis in epithelial cells. However, no systematic study of SCNN1 family members has been conducted in renal clear cell carcinoma (ccRCC) to date. Objective To investigate the abnormal expression of SCNN1 family in ccRCC and its potential correlation with clinical parameters. Methods The transcription and protein expression levels of SCNN1 family members in ccRCC were analyzed based on the TCGA database, and were confirmed by quantitative RT-PCR and immunohistochemical staining assays, respectively. The area under curve (AUC) was used to evaluate the diagnostic value of SCNN1 family members for ccRCC patients. Results The mRNA and protein expression of SCNN1 family members was significantly downregulated in ccRCC compared with normal kidney tissues, which might be due to DNA hypermethylation in the promoter region. It is worth noting that the AUC of SCNN1A, SCNN1B, and SCNN1G were 0.965, 0.979, and 0.988 based on the TCGA database (p < 0.0001), respectively. The diagnostic value was even higher when combing these three members together (AUC = 0.997, p < 0.0001). Intriguingly, the mRNA level of SCNN1A was significantly lower in females compared with males, while SCNN1B and SCNN1G were increased with the progression of ccRCC and remarkably associated with a worse outcome for patients. Conclusion The aberrantly decrease of SCNN1 family members might serve as valuable biomarkers for the diagnosis of ccRCC.

An improved kernel principal component analysis based on sparse representation for face recognition

( Wei Huang ),( Xiaohui Wang ),( Yinghui Zhu ),( Gengzhong Zheng ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.6

Representation based classification, kernel method and sparse representation have received much attention in the field of face recognition. In this paper, we proposed an improved kernel principal component analysis method based on sparse representation to improve the accuracy and robustness for face recognition. First, the distances between the test sample and all training samples in kernel space are estimated based on collaborative representation. Second, S training samples with the smallest distances are selected, and Kernel Principal Component Analysis (KPCA) is used to extract the features that are exploited for classification. The proposed method implements the sparse representation under ℓ₂ regularization and performs feature extraction twice to improve the robustness. Also, we investigate the relationship between the accuracy and the sparseness coefficient, the relationship between the accuracy and the dimensionality respectively. The comparative experiments are conducted on the ORL, the GT and the UMIST face database. The experimental results show that the proposed method is more effective and robust than several state-of-the-art methods including Sparse Representation based Classification (SRC), Collaborative Representation based Classification (CRC), KCRC and Two Phase Test samples Sparse Representation (TPTSR).

AN ULTRA-LUMINOUS QUASAR AT <i>z</i> = 5.363 WITH A TEN BILLION SOLAR MASS BLACK HOLE AND A METAL-RICH DLA AT <i>z</i> ∼ 5

Wang, Feige,Wu, Xue-Bing,Fan, Xiaohui,Yang, Jinyi,Cai, Zheng,Yi, Weimin,Zuo, Wenwen,Wang, Ran,McGreer, Ian D.,Ho, Luis C.,Kim, Minjin,Yang, Qian,Bian, Fuyan,Jiang, Linhua IOP Publishing 2015 ASTROPHYSICAL JOURNAL LETTERS - Vol.807 No.1

<P>We report the discovery of an ultra-luminous quasar J030642.51+185315.8 (hereafter J0306+1853) at redshift 5.363, which hosts a supermassive black hole with M-BH = (1.07 +/- 0.27) x 10(10) M-circle dot. With an absolute magnitude M-1450 = -28.92 and a bolometric luminosity L-bol similar to 3.4 x 10(14) L-circle dot, J0306+1853 is one of the most luminous objects in the early universe. It is not likely to be a beamed source based on its small flux variability, low radio loudness, and normal broad emission lines. In addition, a z = 4.986 damped Ly alpha system (DLA) with [M/H] = -1.3 +/- 0.1, among the most metal-rich DLAs at z greater than or similar to 5, is detected in the absorption spectrum of this quasar. This ultra-luminous quasar puts strong constraints on the bright end of the quasar luminosity function and massive end of the black hole mass function. It will provide a unique laboratory for the study of BH growth and the co-evolution between a BH and the host galaxy with multi-wavelength follow-up observations. The future high-resolution spectra will give more insight into the DLA and other absorption systems along the line of sight of J0306+1853.</P>

Diffusion mechanism of deep shale gas and its carbon isotope fractionation: a combined simulated and mathematical analysis

Yu Zou,Guojian Wang,Cheng Tao,Rui Zhou,Shangqing Zhang,Dongna Liu,Xiaohui Lin,Xuying Zheng 한국지질과학협의회 2023 Geosciences Journal Vol.27 No.3

Unlike the release pressure process in shale gas exploitation, in this study, the concentration diffusion process is deeply discussed under constant temperature-pressure conditions, which aims to evaluate the preservation conditions of shale gas reservoirs in combination with isotopic fractionation characteristics. The isobaric diffusion experiment emphasized that decreasing pressure can lead to enhanced diffusion and isotope fractionation. The established mathematical model not only confirms the results of the simulating experiment, but also suggests that the contributions of Fick, Knudsen and surface diffusion to the migration of methane (including 12CH4 and 13CH4) vary in the geological evolution of shale reservoirs, which are mainly controlled by the pore system and gas pressure. Based on the analysis of specific samples of Longmaxi shale (r = 11.7 nm) and Niutitang shale (r = 1.3 nm), we propose that: 1) high pressure condition (> 20 MPa) can significantly limit Knudsen diffusion, which is the reason for reducing the total diffusion coefficient (DTotal) and isotope fractionation, while low pressure (< 10 MPa) and small pore radius (ca. 1 nm) can strengthen the fractionation; 2) pore connectivity and heterogeneity can lead to an order of magnitude change in DTotal, while the influence of temperature is relatively small. According to the mathematical model, it can be expected that enhanced dissipation intensity and isotope fractionation of shale gas may occur in the process of basin uplift and pressure relief, which can potentially be used for the evaluation of reservoir preservation.

Bidirectional two-sample mendelian randomization analysis identifies causal associations between age at menarche and sarcopenia-related traits

Fan Wei,Gu Peng,Pu Bin,Yue Dan,Xin Qiao,Zheng XiaoHui,Zeng ZhanPeng,Fan Shaoyong 한국유전학회 2023 Genes & Genomics Vol.45 No.8

Background Observational studies have shown that the age of menarche is associated with sarcopenia, but confounding factors make the causal relationship difficult to infer. Objective Therefore, we conducted a bidirectional two-sample Mendelian randomized (MR) analysis to evaluate the potential causal relationship between age at menarche and sarcopenia-related traits (hand grip strength, lean mass, walking pace). Methods We obtained the latest aggregate statistics from the Genome-wide association studies (GWAS) database on the age of menarche of 182,416 participants from ReproGen, the appendicular lean mass of 244,730 participants from EMBL’s European Bioinformatics Institute, the left-hand grip strength of 401,026 participants, the right-hand grip strength of 461,089 participants and the usual walking pace of 459,915 participants from the UK Biobank. The inverse variance weighting (IVW) method and other MR methods were used to evaluate the bidirectional causal relationship between the age of menarche and sarcopenia. Results The forward MR results showed that the age of menarche predicted by the gene was positively correlated with left-hand grip strength (IVWβ=0.041, P = 2.00 × 10−10), right-hand grip strength (IVWβ=0.053, P = 1.97 × 10−18), appendicular lean mass (IVWβ=0.012, P = 4.38 × 10−13) and usual walking pace (IVWβ=0.033, P = 1.62 × 10−8).In the reverse MR analysis, we also found that the usual walking pace was positively correlated with the age of menarche predicted by genes (IVWβ=0.532, P = 1.65 × 10−4). Still, there was no causal relationship between grip strength and appendicular lean mass and the age at menarche. Conclusion Our results show that earlier menarche will increase the risk of sarcopenia. In addition, people with higher muscle function tend to have menarche later. These findings may provide a reference for prevention strategies and interventions for menarche in advance and sarcopenia.

Liquid Chromatography Quadrupole Time-Of-Flight Tandem Mass Spectrometry for Selective Determination of Usnic Acid and Application in Pharmacokinetic Study

Fang, Minfeng,Wang, Hui,Wu, Yang,Wang, Qilin,Zhao, Xinfeng,Zheng, Xiaohui,Wang, Shixiang,Zhao, Guifang Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.6

A rapid and sensitive method for determining usnic acid of Lethariella cladonioides in rat was established using high performance liquid chromatography (HPLC) quadrupole time-of-flight (QTOF) tandem mass (MS/MS). Rat plasma was pretreated by mixture of acetonitrile and chloroform to precipitate plasma proteins. Chromatographic separation was achieved on a column ($50{\times}2.1$ mm, $5{\mu}m$) with a mobile phase consisting of water (containing $5{\times}10^{-3}$ M ammonium formate, pH was adjusted to 3.0 with formic acid) and acetonitrile (20:80, v/v) at a flow rate of 0.3 mL/min. A tandem mass spectrometric detection with an electrospray ionization (ESI) interface was conducted via collision induced dissociation (CID) under negative ionization mode. The MS/MS transitions monitored were m/z 343.0448 ${\rightarrow}$ m/z 313.2017 for usnic acid and m/z 153.1024 ${\rightarrow}$ m/z 136.2136 for protocatechuic acid (internal standard). The linear range was calculated to be 2.0-160.0 ng/mL with a detection limit of 3.0 pg/mL. The inter- and intra-day accuracy and precision were within ${\pm}7.0%$. Pharmacokinetic study showed that the apartment of usnic acid in vivo confirmed to be a two compartment open model. The method was fully valid and will probably be an alternative for pharmacokinetic study of usnic acid.

Hepatitis B Virus Core Protein Mediates the Upregulation of C5α Receptor 1 via NF-κB Pathway to Facilitate the Growth and Migration of Hepatoma Cells

Fanyun Kong,Yukai Tao,Dongchen Yuan,Ning Zhang,Qi Li,Tong Yu,Xiaoying Yang,Delong Kong,Xiaohui Ding,Xiangye Liu,Hongjuan You,Kuiyang Zheng,Renxian Tang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.2

Purpose C5α receptor 1 (C5ΑR1) is associated with the development of various human cancers. However, whether it is involved in the development of hepatitis B virus (HBV)–related hepatocellular carcinoma (HCC) is poorly understood. We explored the expression, biological role, and associated mechanisms of C5AR1 in HBV-related hepatoma cells. Materials and Methods The expression of C5ΑR1 mediated by HBV and HBV core protein (HBc) was detected in hepatoma cells. The function of nuclear factor кB (NF-κB) pathway in HBc-induced C5AR1 expression was assessed. The roles of C5ΑR1 in the activation of intracellular signal pathways, the upregulation of inflammatory cytokines, and the growth and migration of hepatoma cells mediated by HBc, were investigated. The effect of C5α in the development of HCC mediated by C5AR1 was also measured. Results C5ΑR1 expression was increased in HBV-positive hepatoma cells. Dependent on HBc, HBV enhanced the expression of C5ΑR1 at the mRNA and protein levels. Besides, HBc could promote C5ΑR1 expression via the NF-κB pathway. Based on the C5ΑR1, HBc facilitated the activation of JNK and ERK pathways and the expression and secretion of interleukin-6 in hepatoma cells. Furthermore, C5ΑR1 was responsible for enhancing the growth and migration of hepatoma cells mediated by HBc. Except these, C5α could promote the malignant development of HBc-positive HCC via C5AR1. Conclusion We provide new insight into the mechanisms of hepatocarcinogenesis mediated by HBc. C5ΑR1 has a significant role in the functional abnormality of hepatoma cells mediated by HBc, and might be utilized as a potential therapeutic target for HBV-related HCC.