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  1. Article ; Online: Characterization of submicron particles during biomass burning and coal combustion periods in Beijing, China.

    Zhang, J K / Cheng, M T / Ji, D S / Liu, Z R / Hu, B / Sun, Y / Wang, Y S

    The Science of the total environment

    2016  Volume 562, Page(s) 812–821

    Abstract: An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the ... ...

    Abstract An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the biomass burning period (October 1 to 27; BBP) and the coal combustion period (December 10 to 31; CCP) in Beijing in 2014. The average PM1 mass concentrations during the BBP and CCP were 82.3 and 37.5μgm(-3), respectively. Nitrate, ammonium and other pollutants emitted by the burning processes, especially coal combustion, increased significantly in association with increased pollution levels. Positive matrix factorization (PMF) was applied to a unified high-resolution mass spectra database of organic species with NO(+) and NO2(+) ions to discover the relationships between organic and inorganic species. One inorganic factor was identified in both periods, and another five and four distinct organic factors were identified in the BBP and CCP, respectively. Secondary organic aerosols (SOAs) accounted for 55% of the total organic aerosols (OAs) during the BBP, which is higher than the proportion during the CCP (oxygenated OA, 40%). The organic nitrate and inorganic nitrate were first successfully separated through the PMF analysis based on the HR-ToF-AMS observations in Beijing, and organic nitrate components accounted for 21% and 18% of the total nitrate mass during the BBP and CCP, respectively. Although the PM1 mass concentration during the CCP was much lower than in the BBP, the average concentration of polycyclic aromatic hydrocarbons (PAHs) during the CCP (107.3±171.6ngm(-3)) was ~5 times higher than that in the BBP (21.9±21.7ngm(-3)).
    Language English
    Publishing date 2016-08-15
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 121506-1
    ISSN 1879-1026 ; 0048-9697
    ISSN (online) 1879-1026
    ISSN 0048-9697
    DOI 10.1016/j.scitotenv.2016.04.015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Characterization of submicron particles during biomass burning and coal combustion periods in Beijing, China

    Zhang, J.K / Cheng, M.T / Ji, D.S / Liu, Z.R / Hu, B / Sun, Y / Wang, Y.S

    Science of the total environment. 2016 Aug. 15, v. 562

    2016  

    Abstract: An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the ... ...

    Abstract An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the biomass burning period (October 1 to 27; BBP) and the coal combustion period (December 10 to 31; CCP) in Beijing in 2014. The average PM1 mass concentrations during the BBP and CCP were 82.3 and 37.5μgm−3, respectively. Nitrate, ammonium and other pollutants emitted by the burning processes, especially coal combustion, increased significantly in association with increased pollution levels. Positive matrix factorization (PMF) was applied to a unified high-resolution mass spectra database of organic species with NO+ and NO2+ ions to discover the relationships between organic and inorganic species. One inorganic factor was identified in both periods, and another five and four distinct organic factors were identified in the BBP and CCP, respectively. Secondary organic aerosols (SOAs) accounted for 55% of the total organic aerosols (OAs) during the BBP, which is higher than the proportion during the CCP (oxygenated OA, 40%). The organic nitrate and inorganic nitrate were first successfully separated through the PMF analysis based on the HR-ToF-AMS observations in Beijing, and organic nitrate components accounted for 21% and 18% of the total nitrate mass during the BBP and CCP, respectively. Although the PM1 mass concentration during the CCP was much lower than in the BBP, the average concentration of polycyclic aromatic hydrocarbons (PAHs) during the CCP (107.3±171.6ngm−3) was ~5 times higher than that in the BBP (21.9±21.7ngm−3).
    Keywords aerosols ; biomass ; burning ; coal ; combustion ; databases ; ions ; nitrates ; particulates ; pollutants ; polycyclic aromatic hydrocarbons ; spectrometers ; China
    Language English
    Dates of publication 2016-0815
    Size p. 812-821.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 121506-1
    ISSN 1879-1026 ; 0048-9697
    ISSN (online) 1879-1026
    ISSN 0048-9697
    DOI 10.1016/j.scitotenv.2016.04.015
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Isolation and characterization of multipotent stem cells from human cruciate ligaments.

    Cheng, M-T / Yang, H-W / Chen, T-H / Lee, O K-S

    Cell proliferation

    2009  Volume 42, Issue 4, Page(s) 448–460

    Abstract: Objectives: Mesenchymal stem cells have great potential for tissue regeneration, and these cells can be harvested from a variety of tissues; however, up to now it has not been clear whether stem cells could be isolated from cruciate ligaments of the ... ...

    Abstract Objectives: Mesenchymal stem cells have great potential for tissue regeneration, and these cells can be harvested from a variety of tissues; however, up to now it has not been clear whether stem cells could be isolated from cruciate ligaments of the knee joint. The aim of our study was to isolate and characterize stem cells from both anterior and posterior cruciate ligaments (ACL and PCL) of humans.
    Materials and methods: Cruciate ligaments were obtained from patients receiving total knee arthroplasty for advanced osteoarthritis and plastic-adherent cells were serially passaged. In vitro chondrogenic, osteogenic and adipogenic abilities of the cells were evaluated by reverse transcriptase-polymerase chain reaction and histological study. Karyotyping and surface immunophenotyping of the cells were performed.
    Results: It was found that a population of ligament-derived cells could be expanded and subcultured extensively. These cells were able to differentiate into osteoblasts, chondrocytes and adipocytes under appropriate inductions. Their phenotypic characteristics were similar to those of bone marrow mesenchymal stem cells. Karyotyping was normal after serial passage.
    Conclusions: In summary, our study demonstrates that human multipotent stem cells can be isolated and expanded from human ACL and PCL, which are easily obtained from patients following total knee or cruciate ligament reconstructive surgery. Self-renewal and mesodermal differentiation potential of these cells make them a viable alternative source for use in regenerative medicine.
    MeSH term(s) Adipogenesis ; Aged ; Anterior Cruciate Ligament/cytology ; Cell Culture Techniques ; Cell Differentiation ; Cell Proliferation ; Cell Separation ; Chondrogenesis ; Female ; Gene Expression ; Humans ; Karyotyping ; Knee Joint/cytology ; Male ; Mesenchymal Stem Cells/cytology ; Mesenchymal Stem Cells/immunology ; Middle Aged ; Multipotent Stem Cells/cytology ; Multipotent Stem Cells/immunology ; Osteogenesis ; Phenotype ; Posterior Cruciate Ligament/cytology ; Synovial Membrane/cytology
    Language English
    Publishing date 2009-05-29
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1064202-x
    ISSN 1365-2184 ; 0008-8730 ; 0960-7722
    ISSN (online) 1365-2184
    ISSN 0008-8730 ; 0960-7722
    DOI 10.1111/j.1365-2184.2009.00611.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Successful treatment of mesenteric vasculitis caused by Henoch-Schönlein purpura with methylprednisolone pulse therapy.

    Wang, L / Huang, F-C / Ko, S-F / Cheng, M-T

    Clinical rheumatology

    2003  Volume 22, Issue 2, Page(s) 140–142

    Abstract: Although mesenteric vasculitis due to Henoch-Schönlein purpura (HSP) is relatively uncommon, it is the most life-threatening manifestation associated with high mortality. We describe a 15-year-old boy with HSP who had massive gastrointestinal bleeding ... ...

    Abstract Although mesenteric vasculitis due to Henoch-Schönlein purpura (HSP) is relatively uncommon, it is the most life-threatening manifestation associated with high mortality. We describe a 15-year-old boy with HSP who had massive gastrointestinal bleeding and ileus but delayed onset of the purpuric rash. Abdominal ultrasonography revealed thickening of both small and large intestinal walls, and CT found prominent mesenteric vessels with comb sign and double wall of the bowel. These findings were consistent with mesenteric vasculitis and bowel ischaemia. The ischaemic intestine recovered after methylprednisolone pulse therapy and surgical intervention was avoided. Our report suggests that corticosteroid pulse therapy may help controlling HSP with massive gastrointestinal haemorrhage and ischaemic bowel due to widespread mesenteric vasculitis.
    MeSH term(s) Adolescent ; Anti-Inflammatory Agents/administration & dosage ; Exanthema/etiology ; Gastrointestinal Hemorrhage/etiology ; Humans ; Intestines/blood supply ; Ischemia/etiology ; Male ; Mesenteric Arteries ; Methylprednisolone/administration & dosage ; Pulse Therapy, Drug ; Purpura, Schoenlein-Henoch/complications ; Purpura, Schoenlein-Henoch/diagnosis ; Purpura, Schoenlein-Henoch/drug therapy ; Treatment Outcome ; Vasculitis/drug therapy ; Vasculitis/etiology
    Chemical Substances Anti-Inflammatory Agents ; Methylprednisolone (X4W7ZR7023)
    Language English
    Publishing date 2003-05
    Publishing country Germany
    Document type Case Reports ; Journal Article
    ZDB-ID 604755-5
    ISSN 0770-3198
    ISSN 0770-3198
    DOI 10.1007/s10067-002-0676-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Coherent control of a V-type three-level system in a single quantum dot.

    Wang, Q Q / Muller, A / Cheng, M T / Zhou, H J / Bianucci, P / Shih, C K

    Physical review letters

    2005  Volume 95, Issue 18, Page(s) 187404

    Abstract: In a semiconductor quantum dot, the IIx and IIy transitions to the polarization eigenstates, |x> and |y>, naturally form a three-level V-type system. Using low-temperature polarized photoluminescence spectroscopy, we have investigated the exciton ... ...

    Abstract In a semiconductor quantum dot, the IIx and IIy transitions to the polarization eigenstates, |x> and |y>, naturally form a three-level V-type system. Using low-temperature polarized photoluminescence spectroscopy, we have investigated the exciton dynamics arising under strong laser excitation. We also explicitly solved the density matrix equations for comparison with the experimental data. The polarization of the exciting field controls the coupling between the otherwise orthogonal states. In particular, when the system is initialized into \Y>, a polarization-tailored pulse can swap the population into |x>, and vice versa, effectively operating on the exciton spin.
    Language English
    Publishing date 2005-10-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.95.187404
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Characteristics of aerosols collected in central Taiwan during an Asian dust event in spring 2000.

    Cheng, M T / Lin, Y C / Chio, C P / Wang, C F / Kuo, C Y

    Chemosphere

    2005  Volume 61, Issue 10, Page(s) 1439–1450

    Abstract: Aerosol samples for PM(2.5) and PM(2.5-10) were collected at four locations in central Taiwan from 26 to 31 March 2000, a period that experienced exceedingly high PM levels from 29 to 30 March due to the passage of an Asian dust storm. The samples were ... ...

    Abstract Aerosol samples for PM(2.5) and PM(2.5-10) were collected at four locations in central Taiwan from 26 to 31 March 2000, a period that experienced exceedingly high PM levels from 29 to 30 March due to the passage of an Asian dust storm. The samples were analyzed for mass, metallic elements, ions, and carbon. The purpose of this paper is to investigate the influence of the dust storm on the characteristics of local ambient particulate matter. The results indicate that the concentrations of the crustal elements Ca, Mg, Al, Fe and the sea salt species Na+ and Cl- in PM(2.5-10) during the dust episode exceed the mean concentrations in the non-dust period by factors of 3.1, 2.9, 2.6, 2.2, 2.3 and 2.1 respectively. Enrichment factors of Ca, Fe, and Mg in PM(2.5-10) during the dust event are close to unity, indicating that these elements are from soil. Reconstruction of aerosol compositions revealed that soil of coarse particulates elevated approximately 50% in the dust event. It is noted that during the dust event, the ratio of Mg/Al in PM(2.5-10) ranged from 0.21 to 0.25 while that of Ca/Al ranged from 0.6 to 0.9, levels more constant than those obtained in non-dust period.
    MeSH term(s) Aerosols/analysis ; Aerosols/chemistry ; Air Movements ; Air Pollutants/analysis ; Aluminum/analysis ; Calcium/analysis ; Chlorides/analysis ; Dust ; Environmental Monitoring/methods ; Iron/analysis ; Magnesium/analysis ; Oceans and Seas ; Particle Size ; Salts/chemistry ; Sodium/analysis ; Taiwan
    Chemical Substances Aerosols ; Air Pollutants ; Chlorides ; Dust ; Salts ; Sodium (9NEZ333N27) ; Aluminum (CPD4NFA903) ; Iron (E1UOL152H7) ; Magnesium (I38ZP9992A) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2005-12
    Publishing country England
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 120089-6
    ISSN 1879-1298 ; 0045-6535 ; 0366-7111
    ISSN (online) 1879-1298
    ISSN 0045-6535 ; 0366-7111
    DOI 10.1016/j.chemosphere.2005.04.120
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: A simple means of making the differential diagnosis of ureterouterine and vesicouterine fistula.

    Sheen, J H / Lin, C T / Jou, Y C / Cheng, M T

    The Journal of urology

    1998  Volume 160, Issue 4, Page(s) 1420–1421

    MeSH term(s) Adult ; Cesarean Section/adverse effects ; Diagnosis, Differential ; Female ; Fistula/diagnostic imaging ; Fistula/etiology ; Humans ; Radiography ; Ureteral Diseases/diagnostic imaging ; Ureteral Diseases/etiology ; Urinary Bladder Fistula/diagnostic imaging ; Urinary Bladder Fistula/etiology ; Urinary Fistula/diagnostic imaging ; Urinary Fistula/etiology ; Uterine Diseases/diagnostic imaging ; Uterine Diseases/etiology
    Language English
    Publishing date 1998-10
    Publishing country United States
    Document type Case Reports ; Journal Article
    ZDB-ID 3176-8
    ISSN 1527-3792 ; 0022-5347
    ISSN (online) 1527-3792
    ISSN 0022-5347
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Rabi oscillation damped by exciton leakage and Auger capture in quantum dots.

    Zhou, H J / Liu, S D / Cheng, M T / Wang, Q Q / Li, Y Y / Xue, Q K

    Optics letters

    2005  Volume 30, Issue 23, Page(s) 3213–3215

    Abstract: The decoherence of Rabi oscillation (RO) caused by biexciton, population leakage to the wetting layer (WL), and Auger capture in semiconductor quantum dots is theoretically analyzed with multilevel optical Bloch equations. The corresponding effects on ... ...

    Abstract The decoherence of Rabi oscillation (RO) caused by biexciton, population leakage to the wetting layer (WL), and Auger capture in semiconductor quantum dots is theoretically analyzed with multilevel optical Bloch equations. The corresponding effects on the quality factor of RO are also discussed. We have found that the biexciton effect is relatively trifling, as the pulse duration is longer than 5 ps. The population leakage to the WL leads to a decrease of the RO average even though the damping rate is similar to that observed in the experiment. Auger capture in quantum dots results in RO damping that is consistent with the experimental data, which implies that Auger capture is an important decoherence process in quantum dots.
    Language English
    Publishing date 2005-03-10
    Publishing country United States
    Document type Journal Article
    ISSN 0146-9592
    ISSN 0146-9592
    DOI 10.1364/ol.30.003213
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: In vivo protective effect of protocatechuic acid on tert-butyl hydroperoxide-induced rat hepatotoxicity

    Liu, C.L / Wang, J.M / Chu, C.Y / Cheng, M.T / Tseng, T.H

    Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association. May 2002. v. 40 (5)

    2002  

    Keywords Hibiscus sabdariffa ; protocatechuic acid ; medicinal properties ; toxicity ; liver ; oxidants ; histopathology ; tyrosine ; phosphorylation ; enzyme activity ; lipoxygenase ; xanthine oxidase ; rats
    Language English
    Dates of publication 2002-05
    Size p. 635-641.
    Document type Article
    ZDB-ID 782617-5
    ISSN 1873-6351 ; 0278-6915
    ISSN (online) 1873-6351
    ISSN 0278-6915
    Database NAL-Catalogue (AGRICOLA)

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  10. Article: Hibiscus protocatechuic acid inhibits lipopolysaccharide-induced rat hepatic damage.

    Lin, W-L / Hsieh, Y-J / Chou, F-P / Wang, C-J / Cheng, M-T / Tseng, T-H

    Archives of toxicology

    2003  Volume 77, Issue 1, Page(s) 42–47

    Abstract: Hibiscus protocatechuic acid (PCA), a phenolic compound found in the dried flowers of Hibiscus sabdariffa L. (Malvaceae), was demonstrated to have an antioxidant effect in vitro and in vivo, and an antitumor property in our previous study. In the present ...

    Abstract Hibiscus protocatechuic acid (PCA), a phenolic compound found in the dried flowers of Hibiscus sabdariffa L. (Malvaceae), was demonstrated to have an antioxidant effect in vitro and in vivo, and an antitumor property in our previous study. In the present study, we used lipopolysaccharide (LPS, an endotoxin) to induce rat liver inducible nitric oxide synthase (iNOS), and found that pretreatment with PCA decreased the liver iNOS and the serum total nitrite induced by LPS. Our investigation showed that pretreatment of rats with PCA (0.2 and 0.5 mmol/kg dosed by gavage) for 5 days significantly decreased the serum levels of the hepatic enzyme markers alanine- and aspartate aminotransferase (ALT, alanine aminotransferase; AST, aspartate aminotransferase) induced by the 6-h treatment with LPS (i.p.; 5 mg/kg). Histopathological evaluation of the rat livers revealed that PCA reduced the incidence of liver lesions induced by LPS, including neutrophil infiltration, congestion, and liver cell swelling induced by LPS in rats. We conclude that PCA, an antioxidant, presents an inhibitory potential on iNOS and hepatic damage induced by LPS.
    MeSH term(s) Administration, Oral ; Alanine Transaminase/blood ; Animals ; Anticarcinogenic Agents/administration & dosage ; Anticarcinogenic Agents/therapeutic use ; Antioxidants/administration & dosage ; Antioxidants/therapeutic use ; Aspartate Aminotransferases/blood ; Chemical and Drug Induced Liver Injury/blood ; Chemical and Drug Induced Liver Injury/pathology ; Chemical and Drug Induced Liver Injury/prevention & control ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; Escherichia coli/immunology ; Hibiscus/chemistry ; Hydroxybenzoates/administration & dosage ; Hydroxybenzoates/therapeutic use ; Lipopolysaccharides/pharmacology ; Liver/drug effects ; Liver/enzymology ; Liver/pathology ; Male ; Nitric Oxide Synthase/antagonists & inhibitors ; Nitric Oxide Synthase/biosynthesis ; Nitric Oxide Synthase Type II ; Rats ; Rats, Sprague-Dawley
    Chemical Substances Anticarcinogenic Agents ; Antioxidants ; Drugs, Chinese Herbal ; Hydroxybenzoates ; Lipopolysaccharides ; protocatechuic acid (36R5QJ8L4B) ; Nitric Oxide Synthase (EC 1.14.13.39) ; Nitric Oxide Synthase Type II (EC 1.14.13.39) ; Nos2 protein, rat (EC 1.14.13.39) ; Aspartate Aminotransferases (EC 2.6.1.1) ; Alanine Transaminase (EC 2.6.1.2)
    Language English
    Publishing date 2003-01
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 124992-7
    ISSN 1432-0738 ; 0340-5761
    ISSN (online) 1432-0738
    ISSN 0340-5761
    DOI 10.1007/s00204-002-0404-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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