Publications by authors named "Xiang-ru Li"

Kombucha, a fermented tea prepared with a symbiotic culture of bacteria and yeast (SCOBY), offers a unique and unpredictable home-brewed fermentation process. Therefore, the need for a controlled kombucha fermentation process has become evident, which requiring a thorough understanding of the microbial composition and its relationship with the metabolites produced. In this study, we investigated the dynamics of microbial communities and metabolites over a 12-day fermentation period of a conventional kombucha-making process.

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Autophagy regulates cell survival (or cell death in several cases), whereas apoptosis regulates cell death. However, the relationship between autophagy and apoptosis and the regulative mechanism is unclear. We report that steroid hormone 20-hydroxyecdysone (20E) promotes switching from autophagy to apoptosis by increasing intracellular calcium levels in the midgut of the lepidopteran insect Helicoverpa armigera.

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The transcriptional co-activator Yki (Yorkie), a member of the Hippo pathway, regulates cell proliferation or apoptosis, depending on its nuclear or cytoplasmic location. However, the upstream factors regulating the subcellular localization of Yki are unclear. We found that the steroid hormone 20-hydroxyecdysone (20E) induces phosphorylation of Yki, causing it to remain in the cytoplasm, where it promotes apoptosis in the midgut of the lepidopteran insect Helicoverpa armigera Yki is expressed in various tissues, with an increase in the epidermis and midgut during early metamorphic molting.

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This paper presents a method to estimate stellar metallicity based on BP neural network and Ca line index. This method trains a BP ANN model from SDSS/SEGUE stellar spectra and parameters provided by SSPP. The values of Teff and the line index of Ca lines are the input of network while the [Fe/H] values are the oputput of the network.

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Purpose: To analyze the changes in epithelial cells, and observe the expression of Bcl-2, Bax and apoptosis in oral lichen planus.

Methods: Thirty five OLP patients and 10 healthy volunteers were enrolled in this study. Immunohistochemical S-ABC was used to detect Bcl-2 and Bax expression in OLP group and control group.

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It is a key task to estimate the atmospheric parameters from the observed stellar spectra in exploring the nature of stars and universe. With our Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST) which begun its formal Sky Survey in September 2012, we are obtaining a mass of stellar spectra in an unprecedented speed. It has brought a new opportunity and a challenge for the research of galaxies.

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The steroid hormone 20-hydroxyecdysone (20E) plays a critical role in insect development, particularly in larval molting and larval-pupal transition. Studies have indicated that 20E transmits its signal via a G protein-coupled receptor (GPCR)-mediated non-genomic pathway before a genomic pathway is initiated. However, the mechanism by which a 20E signal is desensitized remains unclear.

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The authors propose a novel method of feature extraction for stellar spectra parameterization. The basic procedures are: First, stellar spectra are decomposed by multi-scale Harr wavelet and the coefficients with high-frequency are rejected. Secondly, the optimal features are detected by the lasso algorithm.

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The nuclear receptor-mediated genomic pathways of the animal steroid hormones are well known. However, the cell membrane receptor-mediated nongenomic pathways of the animal steroid hormones are little understood. In this study, we report the participation of a G-protein alpha q (Gαq)(1) subunit in the 20E nongenomic pathway in the cell membrane and regulating gene expression during molting and metamorphosis in a lepidopteran insect, Helicoverpa armigera.

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The steroid hormone 20-hydroxyecdysone (20E) initiates insect molting and metamorphosis. By contrast, juvenile hormone (JH) prevents metamorphosis. However, the mechanism by which JH inhibits metamorphosis remains unclear.

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A novel scheme SVR(Haar) is proposed in the present work for automatically estimating the physical parameters of stellar spectra. The observed spectrum is disturbed usually by noise which is caused by the universe radiation, the atmosphere and observation equipment. Furthermore, the noise usually is the component of the spectrum with higher frequency.

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Background: Heat shock protein 90 (Hsp90) interacts with steroid hormone receptors, signaling kinases, and various transcription factors. However, the mechanism by which Hsp90 interacts with different proteins in various pathways remains unclear.

Methods: Western blot was used to study Hsp90 expression profile in Helicoverpa armigera (Lepidoptera).

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The present paper researches the automatic measurement of the physical parameters ofthe stellar spectra. It is an important problem of the automatic processing of mass spectral data in the large-scale survey plan. The basic steps of the program in this article are: at first, the stellar spectra are decomposed by multi-scale Harr wavelet.

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Purpose: To investigate the expression and relationship of substance P(SP) and vascular endothelial growth factor (VEGF) in human dental pulp under the normal and pathological conditions, so as to study their role in pulp microcirculation. METHONDS: Ten teeth extracted for orthodontic or impacted reason were chosen as normal group. Twenty-nine traumatic teeth from the same age group needing root canal therapy were divided to initial-stage trauma group, early-stage inflammation group, later-stage inflammation group.

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Purpose: To study the distribution of stress of simulating teeth with wedge-shaped defects in the cervical region.

Methods: The models of anisotropic enamel of the mandibular first premolar and the opposite maxillary first premolar crown were created. A defect was introduced into the model of mandibular premolar in the buccal cervical region along the enamelo-dentinal junction.

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[Efficient computation of spectral flux normalization].

Guang Pu Xue Yu Guang Pu Fen Xi

January 2012

Flux normalization is a key procedure in spectral data mining, and is important for the efficiency and accuracy of automatic processing of massive astronomical spectral data, information extraction and sharing. Since the usual implementation of flux normalizing methods is inefficient, the present work focuses on the algorithm designing of spectral flux normalization. Firstly, the authors investigated the limit efficiency characteristics of the available flux normalization methods, introduced four efficient flux normalizing algorithms, and studied their time complexity and space complexity.

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The present focuses on the celestial spectra feature extraction problem, which is a key procedure in automatic spectra classification. By extracting features, the authors can reduce redundancy, alleviate noise influence, and improve accuracy and efficiency in spectra classification. The authors introduced a novel feature analysis framework STP (space transformation and partition), which focuses on four essential components in feature extraction: decompose and reorganize spectrum components, reorganize, alleviate noise influence and eliminate redundancy.

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With the wide application of high-quality CCD in celestial spectrum imagery and the implementation of many large sky survey programs (e. g., Sloan Digital Sky Survey (SDSS), Two-degree-Field Galaxy Redshift Survey (2dF), Spectroscopic Survey Telescope (SST), Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) program and Large Synoptic Survey Telescope (LSST) program, etc.

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Purpose: To evaluate the clinical effects of flowable composite as a liner in treatment of wedge-shaped defects.

Methods: Three hundred and sixty teeth from 85 patients with wedge-shaped defects were studied. The self-control design was used in this study.

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With recent technological advances in wide field survey astronomy and implementation of several large-scale astronomical survey proposals (e. g. SDSS, 2dF and LAMOST), celestial spectra are becoming very abundant and rich.

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Objective: To investigate the efficacy and possible action mechanism of Qianlie Beixi Capsule in the treatment of unliquefiable semen.

Methods: A total of 240 patients with unliquefiable semen were randomly divided into a treatment group (n = 180), treated with Qianlie Beixi Capsule, and a control group (n = 60), given compound tablets of zinc and protein. The treatment lasted two courses of 45 days each, and the seminal changes were observed and recorded.

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Aim: To investigate the apoptotic mechanism of pseudolaric acid B (PAB) in human breast cancer MCF-7 cells.

Methods: 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide analysis and morphological changes were applied to detect apoptosis. The percentage of apoptotic and necrotic cells were calculated by the lactate dehydrogenase activity-based cytotoxicity assay, and the protein expression was examined by Western blot analysis.

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With the recent technological advances in wide field survey astronomy and the implementation of several large scale astronomical survey proposals, celestial spectra are becoming very rich and the study of automated processing methods is attracting more and more attention. In the present work, the authors pointed out that it is necessary to investigate supervised feature extraction by analyzing the characteristics of the spectra classification research in literature and the limitations of unsupervised feature extraction methods. And the authors studied supervised feature extraction based on Fisher discriminant analysis (FDA) and its application in galaxy spectra classification.

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Celestial spectra should be preprocessed before automated classification to eliminate the disturbance of noise, observa-tion environment, and flux aberrance. In the present work, the authors studied the spectrum flux standardization problem. By analyzing the disturbing factors and their characteristics, the authors put forward a theoretical model for spectra flux, and corre-spondingly give several flux standardizing methods.

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The LAMOST project, the world's largest sky survey project being implemented in China, is expected to obtain 10(5) quasar spectra. The main objective of the present article is to explore methods that can be used to estimate the redshifts of quasar spectra from LAMOST. Firstly, the features of the broad emission lines are extracted from the quasar spectra to overcome the disadvantage of low signal-to-noise ratio.

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