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1.
Proc Natl Acad Sci U S A ; 120(45): e2304179120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37903265

RESUMEN

The unexpected discovery of hot Jupiters challenged the classical theory of planet formation inspired by our solar system. Until now, the origin and evolution of hot Jupiters are still uncertain. Determining their age distribution and temporal evolution can provide more clues into the mechanism of their formation and subsequent evolution. Using a sample of 383 giant planets around Sun-like stars collected from the kinematic catalogs of the Planets Across Space and Time project, we find that hot Jupiters are preferentially hosted by relatively younger stars in the Galactic thin disk. We subsequently find that the frequency of hot Jupiters declines with age as [Formula: see text]. In contrast, the frequency of warm/cold Jupiters shows no significant dependence on age. Such a trend is expected from the tidal evolution of hot Jupiters' orbits, and our result offers supporting evidence using a large sample. We also perform a joint analysis on the planet frequencies in the stellar age-metallicity plane. The result suggests that the frequencies of hot Jupiters and warm/cold Jupiters, after removing the age dependence are both correlated with stellar metallicities as [Formula: see text] and [Formula: see text], respectively. Moreover, we show that the above correlations can explain the bulk of the discrepancy in hot Jupiter frequencies inferred from the transit and radial velocity (RV) surveys, given that RV targets tend to be more metal-rich and younger than transits.

2.
Nat Mater ; 23(4): 486-491, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38278983

RESUMEN

A hallmark of many unconventional superconductors is the presence of many-body interactions that give rise to broken-symmetry states intertwined with superconductivity. Recent resonant soft X-ray scattering experiments report commensurate 3a0 charge density wave order in infinite-layer nickelates, which has important implications regarding the universal interplay between charge order and superconductivity in both cuprates and nickelates. Here we present X-ray scattering and spectroscopy measurements on a series of NdNiO2+x samples, which reveal that the signatures of charge density wave order are absent in fully reduced, single-phase NdNiO2. The 3a0 superlattice peak instead originates from a partially reduced impurity phase where excess apical oxygens form ordered rows with three-unit-cell periodicity. The absence of any observable charge density wave order in NdNiO2 highlights a crucial difference between the phase diagrams of cuprate and nickelate superconductors.

3.
Stud Mycol ; 101: 121-243, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36059895

RESUMEN

Chaetomiaceae comprises phenotypically diverse species, which impact biotechnology, the indoor environment and human health. Recent studies showed that most of the traditionally defined genera in Chaetomiaceae are highly polyphyletic. Many of these morphology-based genera, such as Chaetomium, Thielavia and Humicola, have been redefined using multigene phylogenetic analysis combined with morphology; however, a comprehensive taxonomic overview of the family is lacking. In addition, the phylogenetic relationship of thermophilic Chaetomiaceae species with non-thermophilic taxa in the family is largely unclear due to limited taxon sampling in previous studies. In this study, we provide an up-to-date overview on the taxonomy and phylogeny of genera and species belonging to Chaetomiaceae, including an extensive taxon sampling of thermophiles. A multigene phylogenetic analysis based on the ITS (internal transcribed spacers 1 and 2 including the 5.8S nrDNA), LSU (D1/D2 domains of the 28S nrDNA), rpb2 (partial RNA polymerase II second largest subunit gene) and tub2 (ß-tubulin gene) sequences was performed on 345 strains representing Chaetomiaceae and 58 strains of other families in Sordariales. Divergence times based on the multi-gene phylogeny were estimated as aid to determine the genera in the family. Genera were delimited following the criteria that a genus must be a statistically well-supported monophyletic clade in both the multigene phylogeny and molecular dating analysis, fall within a divergence time of over 27 million years ago, and be supported by ecological preference or phenotypic traits. Based on the results of the phylogeny and molecular dating analyses, combined with morphological characters and temperature-growth characteristics, 50 genera and 275 species are accepted in Chaetomiaceae. Among them, six new genera, six new species, 45 new combinations and three new names are proposed. The results demonstrate that the thermophilic species fall into seven genera (Melanocarpus, Mycothermus, Remersonia, Thermocarpiscus gen. nov., Thermochaetoides gen. nov., Thermothelomyces and Thermothielavioides). These genera cluster in six separate lineages, suggesting that thermophiles independently evolved at least six times within the family. A list of accepted genera and species in Chaetomiaceae, together with information on their MycoBank numbers, living ex-type strains and GenBank accession numbers to ITS, LSU, rpb2 and tub2 sequences is provided. Furthermore, we provide suggestions how to describe and identify Chaetomiaceae species. Taxonomic novelties: new genera: Parvomelanocarpus X.Wei Wang & Houbraken, Pseudohumicola X.Wei Wang, P.J. Han, F.Y. Bai & Houbraken, Tengochaeta X.Wei Wang & Houbraken, Thermocarpiscus X.Wei Wang & Houbraken, Thermochaetoides X.Wei Wang & Houbraken, Xanthiomyces X.Wei Wang & Houbraken; New species: Botryotrichum geniculatum X.Wei Wang, P.J. Han & F.Y. Bai, Chaetomium subaffine Sergejeva ex X.Wei Wang & Houbraken, Humicola hirsuta X.Wei Wang, P.J. Han & F.Y. Bai, Subramaniula latifusispora X.Wei Wang, P.J. Han & F.Y. Bai, Tengochaeta nigropilosa X.Wei Wang & Houbraken, Trichocladium tomentosum X.Wei Wang, P.J. Han & F.Y. Bai; New combinations: Achaetomiella gracilis (Udagawa) Houbraken, X.Wei Wang, P.J. Han & F.Y. Bai, Allocanariomyces americanus (Cañete-Gibas et al.) Cañete-Gibas, Wiederhold, X.Wei Wang & Houbraken, Amesia dreyfussii (Arx) X.Wei Wang & Houbraken, Amesia raii (G. Malhotra & Mukerji) X.Wei Wang & Houbraken, Arcopilus macrostiolatus (Stchigel et al.) X.Wei Wang & Houbraken, Arcopilus megasporus (Sörgel ex Seth) X.Wei Wang & Houbraken, Arcopilus purpurascens (Udagawa & Y. Sugiy.) X.Wei Wang & Houbraken, Arxotrichum deceptivum (Malloch & Benny) X.Wei Wang & Houbraken, Arxotrichum gangligerum (L.M. Ames) X.Wei Wang & Houbraken, Arxotrichum officinarum (M. Raza & L. Cai) X.Wei Wang & Houbraken, Arxotrichum piluliferoides (Udagawa & Y. Horie) X.Wei Wang & Houbraken, Arxotrichum repens (Guarro & Figueras) X.Wei Wang & Houbraken, Arxotrichum sinense (K.T. Chen) X.Wei Wang & Houbraken, Botryotrichum inquinatum (Udagawa & S. Ueda) X.Wei Wang & Houbraken, Botryotrichum retardatum (A. Carter & R.S. Khan) X.Wei Wang & Houbraken, Botryotrichum trichorobustum (Seth) X.Wei Wang & Houbraken, Botryotrichum vitellinum (A. Carter) X.Wei Wang & Houbraken, Collariella anguipilia (L.M. Ames) X.Wei Wang & Houbraken, Collariella hexagonospora (A. Carter & Malloch) X.Wei Wang & Houbraken, Collariella pachypodioides (L.M. Ames) X.Wei Wang & Houbraken, Ovatospora amygdalispora (Udagawa & T. Muroi) X.Wei Wang & Houbraken, Ovatospora angularis (Yu Zhang & L. Cai) X.Wei Wang & Houbraken, Parachaetomium biporatum (Cano & Guarro) X.Wei Wang & Houbraken, Parachaetomium hispanicum (Guarro & Arx) X.Wei Wang & Houbraken, Parachaetomium inaequale (Pidopl. et al.) X.Wei Wang & Houbraken, Parachaetomium longiciliatum (Yu Zhang & L. Cai) X.Wei Wang & Houbraken, Parachaetomium mareoticum (Besada & Yusef) X.Wei Wang & Houbraken, Parachaetomium muelleri (Arx) X.Wei Wang & Houbraken, Parachaetomium multispirale (A. Carter et al.) X.Wei Wang & Houbraken, Parachaetomium perlucidum (Sergejeva) X.Wei Wang & Houbraken, Parachaetomium subspirilliferum (Sergejeva) X.Wei Wang & Houbraken, Parathielavia coactilis (Nicot) X.Wei Wang & Houbraken, Parvomelanocarpus tardus (X.Wei Wang & Samson) X.Wei Wang & Houbraken, Parvomelanocarpus thermophilus (Abdullah & Al-Bader) X.Wei Wang & Houbraken, Pseudohumicola atrobrunnea (X.Wei Wang et al.) X.Wei Wang, P.J. Han, F.Y. Bai & Houbraken, Pseudohumicola pulvericola (X.Wei Wang et al.) X.Wei Wang, P.J. Han, F.Y. Bai & Houbraken, Pseudohumicola semispiralis (Udagawa & Cain) X.Wei Wang, P.J. Han, F.Y. Bai & Houbraken, Pseudohumicola subspiralis (Chivers) X.Wei Wang, P.J. Han, F.Y. Bai & Houbraken, Staphylotrichum koreanum (Hyang B. Lee & T.T.T. Nguyen) X.Wei Wang & Houbraken, Staphylotrichum limonisporum (Z.F. Zhang & L. Cai) X.Wei Wang & Houbraken, Subramaniula lateralis (Yu Zhang & L. Cai) X.Wei Wang & Houbraken, Thermocarpiscus australiensis (Tansey & M.A. Jack) X.Wei Wang & Houbraken, Thermochaetoides dissita (Cooney & R. Emers.) X.Wei Wang & Houbraken, Thermochaetoides thermophila (La Touche) X.Wei Wang & Houbraken, Xanthiomyces spinosus (Chivers) X.Wei Wang & Houbraken; New names: Chaetomium neoglobosporum X.Wei Wang & Houbraken, Thermothelomyces fergusii X.Wei Wang & Houbraken, Thermothelomyces myriococcoides X.Wei Wang & Houbraken; Lecto- and / or epi-typifications (basionyms): Botryoderma rostratum Papendorf & H.P. Upadhyay, Botryotrichum piluliferum Sacc. & Marchal, Chaetomium carinthiacum Sörgel, Thielavia heterothallica Klopotek. Citation: Wang XW, Han PJ, Bai FY, Luo A, Bensch K, Meijer M, Kraak B, Han DY, Sun BD, Crous PW, Houbraken J (2022). Taxonomy, phylogeny and identification of Chaetomiaceae with emphasis on thermophilic species. Studies in Mycology 101: 121-243. doi: 10.3114/sim.2022.101.03.

4.
Zhonghua Zhong Liu Za Zhi ; 43(6): 638-645, 2021 Jun 23.
Artículo en Zh | MEDLINE | ID: mdl-34289555

RESUMEN

Objective: To clarify the function and molecular mechanisms of serpin family E member 2 (SERPINE2) in cellular migration and invasion of esophageal squamous cell carcinoma (ESCC). Methods: The expression of SERPINE2 in ESCC was analyzed by using online databases TCGA (http: //gepia.cancer-pku.cn/detail.php and http: //ualcan.path.uab. edu/index.html). The expressions of SERPINE2 mRNA in normal human esophageal epithelial cell line NE2, human ESCC cell lines KYSE30 and KYSE150 were detected by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). SERPINE2-konckdown or SERPINE2-overexpressed plasmid was transfected into KYSE30 cells, and the efficiencies of the knockdown and overexpression system were tested by qRT-PCR. The relationships of SERPINE2 and ESCC migration and invasion were determined by migration and invasion assays in vitro. The associations between SERPINE2 expression and ß-catenin as well as its target genes including c-Myc, cyclin D1 and CD44 were analyzed by immunofluorescence, qRT-PCR and western blot, respectively. Results: The expressions of SERPINE2 were significantly upregulated in both esophageal cancer (ESCA) and ESCC tissues compared to normal tissues by analyzing 182 and 95 cases, respectively (P<0.01). SERPINE2 is highly expressed in both KYSE30 and KYSE150 cells (P<0.05). The number of migrating and invading cells in control group were (212.66±24.11)/field and (136.00±14.42)/field, while were (88.33±9.71)/field and (77.00±9.53)/field in SERPINE2-knockdown 1 group, and (66.00±8.00)/field and (45.66±3.78)/field in SERPINE2-knockdown 2 group, respectively, and the differences were dramatically significant compared with the control group (P<0.01). The number of migrating and invading cells in control group were (250.00±30.00)/field and (203.33±15.27)/field, while were (383.33±35.11)/field and (246.66±25.16)/field in SERPINE2-overpressed group, and the differences were strikingly significant compared with the control group (P<0.01). The protein expression of ß-catenin was upregulated while phosphorylated ß-catenin protein expression was downregulated in SERPINE2-overexpressed KYSE30 cells when compared to control cells.The transcription activity of ß-catenin was significantly upregulated and the mRNA expressions of its target genes including c-Myc, cyclin D1 and CD44 were all increased. After treated with 25 µM iCRT14, the number of migrated cells in the control and SERPINE2-overpressed groups were (200.00±36.05)/field and (258.33±22.54)/field, and the number of invaded cells were (160.00±17.32)/field and (188.33±25.65)/field, respectively, the differences were dramatically significant compared with the group without iCRT14 treatment (P<0.01). Conclusion: SERPINE2 is significantly upregulated in ESCC cells and can promote cellular migration and invasion by activating ß-catenin, which may provide a potential therapeutic target for patients with ESCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de Cabeza y Cuello , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas de Esófago/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Invasividad Neoplásica , Piridinas , Pirroles , Serpina E2 , Tiazolidinedionas , beta Catenina/genética , beta Catenina/metabolismo
6.
Eur J Clin Microbiol Infect Dis ; 36(7): 1225-1230, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28265816

RESUMEN

This multicenter, double-blind, randomized, parallel-group, non-inferiority study compared the efficacy and safety of morinidazole with those of ornidazole in women with pelvic inflammatory disease. Women from 18 hospitals in China received a 14-day course of either intravenous morinidazole, 500 mg twice daily (n = 168), or intravenous ornidazole, 500 mg twice daily (n = 170). A total of 312 of 338 patients in the full analysis set (FAS) (92.3%) were included in the per protocol set (PPS) analyses, 61 (19.6%) of whom were included in the microbiologically valid (MBV) population. The clinical resolution rates in the PPS population at the test of cure (TOC, primary efficacy end point, 7-30 days post-therapy) visit were 96.86% (154/159) for morinidazole and 96.73% (148/153) for ornidazole (95% CI: -3.79% to 4.03%). The bacteriological success rates in the MBV population at the TOC visit were 100% (32/32) for morinidazole and 89.66% (26/29) for ornidazole (95% CI: -16.15% to 11.21%). Drug-related adverse events occurred less frequently with morinidazole (32.74%, 55/168) than with ornidazole (47.06%, 80/170) (p < 0.01). For women with pelvic inflammatory disease, twice-daily morinidazole for 14 days was clinically and bacteriologically as efficacious as twice-daily ornidazole for 14 days, while the former was associated with fewer drug-related adverse events than the latter.


Asunto(s)
Antiinfecciosos/administración & dosificación , Antiinfecciosos/efectos adversos , Nitroimidazoles/administración & dosificación , Nitroimidazoles/efectos adversos , Enfermedad Inflamatoria Pélvica/tratamiento farmacológico , Administración Intravenosa , Adolescente , Adulto , Anciano , China , Método Doble Ciego , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Persona de Mediana Edad , Ornidazol/administración & dosificación , Ornidazol/efectos adversos , Resultado del Tratamiento , Virosis , Adulto Joven
7.
Anaesthesia ; 71(6): 700-5, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26945818

RESUMEN

The aim of this study was to determine the minimum effective concentration of ropivacaine for ultrasound-guided supraclavicular brachial plexus block. Fifty-one patients undergoing arm surgery received double-injection ultrasound-guided supraclavicular block using ropivacaine 40 ml. The concentration of ropivacaine administered to each patient started at 0.225% and then depended on the response of the previous one, based on a biased coin design up-and-down sequential method. In case of failure, the ropivacaine concentration was increased by 0.025% w/v in the next subject. In the case of a successful block, the next patient was randomised to the same concentration or a concentration 0.025% w/v less. Success was defined as complete sensory blockade of the brachial plexus 30 min after the block together with pain-free surgery. The minimum effective ropivacaine concentration in 90% of subjects was 0.257% w/v (95% CI 0.241-0.280%).


Asunto(s)
Amidas/administración & dosificación , Anestésicos Locales/administración & dosificación , Bloqueo del Plexo Braquial/métodos , Ultrasonografía Intervencional , Amidas/farmacocinética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ropivacaína
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1521-5, 2016 May.
Artículo en Zh | MEDLINE | ID: mdl-30001056

RESUMEN

The redshift measurement of galaxy spectrum is a key issue in large astronomical spectral survey. Its goal is to extract the redshift from spectrum, which is caused the Doppler Effect. With the development of the extragalactic sky survey project, the distance (redshift) of the observed targets is becoming further. As a result, the magnitude of the observed objects becomes darker and the spectral quality becomes poorer. Therefore, how to effectively and accurately measure the redshift from these low quality spectra is becoming an important problem in the extragalactic survey. Considering the spectral features and the data character, a new definition of multi-resolution fusion distance for low quality spectra is proposed. In this paper, we put forward a redshift measuring method for low quality galaxy spectra. This method combines the spectral features with different resolutions. The template spectrum and the spectrum to measure are reduced to the resolution and then a distance is computed by combining the offset of the above two spectra in different wavelengths. Then, a fusion distance is weighted averaged from the distances with different resolutions. In this paper, the effect of signal-to-noise ratio (SNR) on the measuring accuracy of the proposed method is discussed. The measuring accuracy is larger than 90% when the SNR is larger than 5. A large number of experiments show that the method proposed in this paper is very efficient in measuring the redshift of the low-quality galaxy spectra and the measuring error has nothing to do with the redshift value. The proposed method can be applied in redshift measurement of galaxies for the large-scale survey data.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2275-8, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-30036008

RESUMEN

LAMOST-DR1 is the first data released by Guoshoujing telescop, which has the largest number of stellar spectra in the world at present. The data set provides the data source for searching for special and rare celestial objects like cataclysmic variable stars.Meanwhile, it requires more advanced astronomical data processing methods and techniques. A data mining method for cataclysmic variable spectra in massive spectra data is proposed in this paper. Different types of celestial spectra show obvious difference in the feature space constructed with Laplacian Eigenmap method. The parameters of artificial neural network are optimized with particle swarm optimization method and the total LAMOST-DR1 data is processed. 7 cataclysmic variable star spectra are found in the experiment including 2 dwarf nova, 2 nova like variables and a highly polarized AM Her type. The newly found spectra enrich the current cataclysmic variable spectra library. The experiment is the first attempt of searching for cataclysmic variable star spectra with Guoshoujing telescope data and the results show that our approach is feasible in LAMOST data. This method is also applicable for mining other special celestial objects in sky survey telescope data.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2651-4, 2016 Aug.
Artículo en Zh | MEDLINE | ID: mdl-30074723

RESUMEN

Celestial spectrum contains a great deal of astrophysical information. Through the analysis of spectra, people can get the physical information of celestial bodies, as well as their chemical composition and atmospheric parameters. With the implementation of LAMOST, SDSS telescopes and other large-scale surveys, massive spectral data will be produced, especially along with the formal operation of LAMOST, 2 000 to 4 000 spectral data will be generated each observation night. It requires more efficient processing technology to cope with such massive spectra. Automatic classification of stellar spectra is a basic content of spectral processing. The main purpose of this paper is to research the automatic classification of massive stellar spectra. The Lick index is a set of standard indices defined in astronomical spectra to describe the spectral intensity of spectral lines, which represent the physical characteristics of spectra. Lick index is a relatively wide spectral characteristics, each line index is named after the most prominent absorption line. In this paper, the Bayesian method is used to classify stellar spectra based on Lick line index, which divides stellar spectra to three subtypes: F, G, K. First of all, Lick line index of spectra is calculated as the characteristic vector of spectra, and then Bayesian method is used to classify these spectra. For massive spectra, the computation of Lick indices and the spectral classification using Bayesian decision method are implemented on Hadoop. With use of the high throughput and good fault tolerance of HDFS, combined with the advantages of MapReduce parallel programming model, the efficiency of analysis and processing for massive spectral data have been improved significantly. The main innovative contributions of this thesis are as follows. (1) Using Lick indices as the characteristic to classify stellar spectra based on Bayesian decision method. (2) Implementing parallel computation of Lick indices and parallel classification of stellar spectra using Bayesian based on Hadoop MapReduce distributed computing framework.

11.
BMC Complement Altern Med ; 15: 389, 2015 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-26508316

RESUMEN

BACKGROUND: Liver fibrosis is a feature in the majority of chronic liver diseases and oxidative stress is considered to be its main pathogenic mechanism. Antioxidants including vitamin E, are effective in preventing liver fibrogenesis. Several plant-drived antioxidants, such as silymarin, baicalin, beicalein, quercetin, apigenin, were shown to interfere with liver fibrogenesis. The antioxidans above are polyphenols, flavonoids or structurally related compounds which are the main chemical components of Pomegranate peels and seeds, and the antioxidant activity of Pomegranate peels and seeds have been verified. Here we investigated whether the extracts of pomegranate peels (EPP) and seeds (EPS) have preventive efficacy on liver fibrosis induced by carbon tetrachloride (CCl4) in rats and explored its possible mechanisms. METHODS: The animal model was established by injection with 50 % CCl4 subcutaneously in male wistar rats twice a week for four weeks. Meanwhile, EPP and EPS were administered orally every day for 4 weeks, respectively. The protective effects of EPP and EPS on biochemical metabolic parameters, liver function, oxidative markers, activities of antioxidant enzymes and liver fibrosis were determined in CCl4-induced liver toxicity in rats. RESULTS: Compared with the sham group, the liver function was worse in CCl4 group, manifested as increased levels of serum alanine aminotransferase, aspartate aminotransferase and total bilirubin. EPP and EPS treatment significantly ameliorated these effects of CCl4. EPP and EPS attenuated CCl4-induced increase in the levels of TGF-ß1, hydroxyproline, hyaluronic acid laminin and procollagen type III. They also restored the decreased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and inhibited the formation of lipid peroxidized products in rats treated with CCl4. CONCLUSION: The EPP and EPS have protective effects against liver fibrosis induced by CCl4, and its mechanisms might be associated with their antioxidant activity, the ability of decreasing the level of TGF-ß1 and inhibition of collagen synthesis.


Asunto(s)
Cirrosis Hepática/prevención & control , Hígado/efectos de los fármacos , Lythraceae/química , Extractos Vegetales/farmacología , Animales , Biomarcadores/metabolismo , Tetracloruro de Carbono , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Pruebas de Función Hepática , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Semillas/química , Bazo/metabolismo
12.
Clin Exp Obstet Gynecol ; 42(1): 104-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25864293

RESUMEN

PURPOSE: To investigate the cause and preventative measures of late postpartum hemorrhage resulted from placental and fetal membrane residuals. MATERIALS AND METHODS: Retrospective analysis on 161 cases of late postpartum hemorrhage resulting from residuals of placenta and fetal membrane from 2002 to 2012. RESULTS: Among the 161 cases, there were 148 cases of vaginal delivery and 13 cases of cesarean section delivery. One hundred twenty-one cases (4.77%) of placental and fetal membrane residuals were present in 2,535 cases of pregnant women with history of abortion; 40 cases (2.01%) of placental and fetal membrane residuals were found in 1,989 cases of pregnant women without history of abortion. CONCLUSION: Placental and fetal membrane residuals are the major cause of late postpartum hemorrhage. Repeated abortion will increase the incidence of late postpartum hemorrhage resulting from placental and fetal membrane residuals.


Asunto(s)
Parto Obstétrico/efectos adversos , Membranas Extraembrionarias , Hemostasis Quirúrgica/métodos , Placenta , Hemorragia Posoperatoria , Hemorragia Posparto , Aborto Inducido/efectos adversos , Adulto , Antibacterianos/uso terapéutico , Volumen Sanguíneo , Cesárea/efectos adversos , China , Dilatación y Legrado Uterino/métodos , Membranas Extraembrionarias/patología , Membranas Extraembrionarias/cirugía , Femenino , Fluidoterapia/métodos , Humanos , Placenta/patología , Placenta/cirugía , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/fisiopatología , Hemorragia Posoperatoria/terapia , Hemorragia Posparto/etiología , Hemorragia Posparto/fisiopatología , Hemorragia Posparto/terapia , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3524-8, 2015 Dec.
Artículo en Zh | MEDLINE | ID: mdl-26964243

RESUMEN

Distance metric is an important issue for the spectroscopic survey data processing, which defines a calculation method of the distance between two different spectra. Based on this, the classification, clustering, parameter measurement and outlier data mining of spectral data can be carried out. Therefore, the distance measurement method has some effect on the performance of the classification, clustering, parameter measurement and outlier data mining. With the development of large-scale stellar spectral sky surveys, how to define more efficient distance metric on stellar spectra has become a very important issue in the spectral data processing. Based on this problem and fully considering of the characteristics and data features of the stellar spectra, a new distance measurement method of stellar spectra named Residual Distribution Distance is proposed. While using this method to measure the distance, the two spectra are firstly scaled and then the standard deviation of the residual is used the distance. Different from the traditional distance metric calculation methods of stellar spectra, when used to calculate the distance between stellar spectra, this method normalize the two spectra to the same scale, and then calculate the residual corresponding to the same wavelength, and the standard error of the residual spectrum is used as the distance measure. The distance measurement method can be used for stellar classification, clustering and stellar atmospheric physical parameters measurement and so on. This paper takes stellar subcategory classification as an example to test the distance measure method. The results show that the distance defined by the proposed method is more effective to describe the gap between different types of spectra in the classification than other methods, which can be well applied in other related applications. At the same time, this paper also studies the effect of the signal to noise ratio (SNR) on the performance of the proposed method. The result show that the distance is affected by the SNR. The smaller the signal-to-noise ratio is, the greater impact is on the distance; While SNR is larger than 10, the signal-to-noise ratio has little effect on the performance for the classification.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3204-8, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26978937

RESUMEN

We have collected massive stellar spectral data in recent years, which leads to the research on the automatic measurement of stellar atmospheric physical parameters (effective temperature Teff, surface gravity log g and metallic abundance [Fe/ H]) become an important issue. To study the automatic measurement of these three parameters has important significance for some scientific problems, such as the evolution of the universe and so on. But the research of this problem is not very widely, some of the current methods are not able to estimate the values of the stellar atmospheric physical parameters completely and accurately. So in this paper, an automatic method to predict stellar atmospheric parameters based on mass estimation was presented, which can achieve the prediction of stellar effective temperature Teff, surface gravity log g and metallic abundance [Fe/H]. This method has small amount of computation and fast training speed. The main idea of this method is that firstly it need us to build some mass distributions, secondly the original spectral data was mapped into the mass space and then to predict the stellar parameter with the support vector regression (SVR) in the mass space. we choose the stellar spectral data from the United States SDSS-DR8 for the training and testing. We also compared the predicted results of this method with the SSPP and achieve higher accuracy. The predicted results are more stable and the experimental results show that the method is feasible and can predict the stellar atmospheric physical parameters effectively.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2650-3, 2015 Sep.
Artículo en Zh | MEDLINE | ID: mdl-26669184

RESUMEN

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. A set of samples are resampled from the set of all and then a network model is trained. The network can be used to predict the stellar metallicity from low-resolution spsectra. The experiment shows that the proposed method can accurately and effectively measure the [Fe/H] from the stellar spectra.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 834-40, 2015 Mar.
Artículo en Zh | MEDLINE | ID: mdl-26117907

RESUMEN

There are many valuable rare and unusual objects in spectra dataset of Sloan Digital Sky Survey (SDSS) Data Release eight (DR8), such as special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on, so it is extremely significant to search for rare and unusual celestial objects from massive spectra dataset. A novel algorithm based on Kernel dense estimation and K-nearest neighborhoods (KNN) has been presented, and applied to search for rare and unusual celestial objects from 546 383 stellar spectra of SDSS DR8. Their densities are estimated using Gaussian kernel density estimation, the top 5 000 spectra in descend order by their densities are selected as rare objects, and the top 300 000 spectra in ascend order by their densities are selected as normal objects. Then, KNN were used to classify the rest objects, and simultaneously K nearest neighbors of the 5 000 rare spectra are also selected as rare objects. As a result, there are totally 21 193 spectra selected as initial rare spectra, which include error spectra caused by deletion, redden, bad calibration, spectra consisting of different physically irrelevant components, planetary nebulas, QSOs, special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on. By cross identification with SIMBAD, NED, ADS and major literature, it is found that three DZ white dwarfs, one WDMS, two CVs with company of G-type star, three CVs candidates, six DC white dwarfs, one DC white dwarf candidate and one BL Lacertae (BL lac) candidate are our new findings. We also have found one special DA white dwarf with emission lines of Ca II triple and Mg I, and one unknown object whose spectrum looks like a late M star with emission lines and its image looks like a galaxy or nebula.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1099-102, 2015 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-26197609

RESUMEN

The focal ratio degradation (FRD) of optical fiber is one of major sources causing light loss in multi-fiber astronomical instruments. Meanwhile, the sky subtraction is crucial to multi-fiber spectra reduction, especially for the objects which are as faint as the sky background, not to mention for those even fainter ones. To improve the accuracy of sky subtraction, it is necessary to normalize the throughput among object fibers and sky sampling fibers. The rotation and twist during mounting and rotating could change the FRD of individual fibers, which means the variation of the transmission throughput among fibers. We investigate such throughput variation among LAMOST fibers and its correlation with the intensity of sky emission lines on all wavelength coverage in this paper. On the basis of this work, we present an approach to correcting the varied fiber throughput by measuring the intensity of the sky emission lines as the secondary throughput correction. This approach has been applied to LAMOST 2D Pipeline.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1103-6, 2015 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-26197610

RESUMEN

In the present paper, a local mean-based K-nearest centroid neighbor (LMKNCN) technique is used for the classification of stars, galaxies and quasars (QSOS). The main idea of LMKNCN is that it depends on the principle of the nearest centroid neighborhood(NCN), and selects K centroid neighbors of each class as training samples and then classifies a query pattern into the class with the distance of the local centroid mean vector to the samples . In this paper, KNN, KNCN and LMKNCN were experimentally compared with these three different kinds of spectra data which are from the United States SDSS-DR8. Among these three methods, the rate of correct classification of the LMKNCN algorithm is higher than the other two algorithms or comparable and the average rate of correct classification is higher than the other two algorithms, especially for the identification of quasars. Experiment shows that the results in this work have important significance for studying galaxies, stars and quasars spectra classification.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(1): 258-62, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-25993860

RESUMEN

Supernova (SN) is called the "standard candles" in the cosmology, the probability of outbreak in the galaxy is very low and is a kind of special, rare astronomical objects. Only in a large number of galaxies, we have a chance to find the supernova. The supernova which is in the midst of explosion will illuminate the entire galaxy, so the spectra of galaxies we obtained have obvious features of supernova. But the number of supernova have been found is very small relative to the large number of astronomical objects. The time computation that search the supernova be the key to weather the follow-up observations, therefore it needs to look for an efficient method. The time complexity of the density-based outlier detecting algorithm (LOF) is not ideal, which effects its application in large datasets. Through the improvement of LOF algorithm, a new algorithm that reduces the searching range of supernova candidates in a flood of spectra of galaxies is introduced and named SKLOF. Firstly, the spectra datasets are pruned and we can get rid of most objects are impossible to be the outliers. Secondly, we use the improved LOF algorithm to calculate the local outlier factors (LOF) of the spectra datasets remained and all LOFs are arranged in descending order. Finally, we can get the smaller searching range of the supernova candidates for the subsequent identification. The experimental results show that the algorithm is very effective, not only improved in accuracy, but also reduce the operation time compared with LOF algorithm with the guarantee of the accuracy of detection.

20.
Clin Exp Immunol ; 175(2): 316-22, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24666024

RESUMEN

Appendicitis followed by appendectomy (AA) at a young age protects against inflammatory bowel disease (IBD). We wanted to characterize the role of the T helper type 17 (Th17) system involved in this protective effect. AA was performed on 5-week-old male BALB/c mice and distal-colon samples were harvested. Mice with two laparotomies each served as sham-sham (SS) controls. RNA was extracted from four individual colonic samples per group (AA and SS groups) and each sample microarray-analysed and reverse transcription-polymerase chain reaction (RT-PCR)-validated. Gene-set enrichment analysis (GSEA) showed that the Th17 recruitment factor gene CCL20 was significantly suppressed at both 3 days post-AA and 28 days post-AA. Although Th17 cell development differentiation factor genes TGF-ß2 and TGF-ß3 were significantly up-regulated 3 days post-AA, GSEA 28 days post-AA showed that AA down-regulated 29 gene-sets associated with TGF-ß1, TGF-ß2 and TGF-ß3 in contrast to none up-regulated with any of these genes. GSEA showed substantial down-regulation of gene-sets associated with Th17 lymphocyte recruitment, differentiation, activation and cytokine expression in the AA group 28 days post-AA. We conclude that Th17-system cytokines are kept under control by AA via down-regulation of proinflammatory CCL20, a rapid down-regulation of pro-Th17 cell differentiation genes TGF-ß2 and TGF-ß3, suppression of RORC-associated gene-sets, increased protective STAT1 expression and suppression of 81 'pro-Th17' system gene-sets. AA suppresses the Th17 pathway leading to colitis amelioration. Further characterization of Th17-associated genes and biological pathways will assist in the development of better therapeutic approaches in IBD management.


Asunto(s)
Apendicectomía , Apendicitis/cirugía , Colitis/prevención & control , Células Th17/metabolismo , Animales , Apendicitis/inmunología , Apendicitis/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Quimiocina CCL20/metabolismo , Colitis/cirugía , Colon/inmunología , Regulación hacia Abajo , Expresión Génica , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Factor de Transcripción STAT1/metabolismo , Células Th17/inmunología , Factor de Crecimiento Transformador beta2/metabolismo , Factor de Crecimiento Transformador beta3/metabolismo , Regulación hacia Arriba
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