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1.
Chin Med Sci J ; 38(3): 235-241, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37643872

RESUMEN

This data article presents data from the China Migrants Dynamic Survey (CMDS), a multi-wave, large-scale national cross-sectional survey of China's internal migrants from 2009 to 2018. The CMDS is an annual questionnaire survey conducted by the former National Health and Family Planning Commission (NHFPC) of the People's Republic of China. The respondents included in this survey are internal migrants over 15 years old. The sample was drawn from the China Migrant Population Information System, using multi-stage stratified sampling method and the probability proportional-to-size (PPS) cluster sampling strategy. Between 2009 and 2018, there were 1,527,650 internal migrants from 23 provinces, 5 autonomous regions and 4 municipalities participated in the surveys. The survey tools were a series of self-designed questionnaires with high inheritance and consistency designed and implemented by the NHFPC. The questionnaires mainly contain basic information of the respondents and their family members, migration status, healthcare or health behaviors, public health service utilization, social insurance, social integration, and family planning. The dataset is currently the most widely used survey data on China's internal migrants, offering information on migration patterns, healthcare and health behaviors, use of public health services, access to social security, social integration, and family planning, which are valuable for health planning, health decision-making, and health equity research.


Asunto(s)
Servicios de Planificación Familiar , Migrantes , Estados Unidos , Humanos , Adolescente , Estudios Transversales , China/epidemiología , Encuestas y Cuestionarios
2.
Int J Biol Macromol ; 212: 495-507, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35618090

RESUMEN

A new polysaccharide fraction HLP-1 (2.55 × 105 Da) was obtained from the fruiting bodies of Helvella leucopus. Structural characterization of HLP-1 was elucidated by infrared spectroscopy, monosaccharide composition analysis, methylation analysis, nuclear magnetic resonance spectroscopy, scanning electron microscopy and Congo red assay. HLP-1 was a mannan with a backbone of →6)-α-D-Manp(1 â†’ 4)- α-D-Manp(1 â†’6)-α-D-Manp(1 â†’ 3)-α-D-Manp(1 â†’ 4)-α-D-Manp(1 â†’ 3)-α-D-Manp(1→, which branched at the O-6 position and terminated with T-ß-D-Manp. Moreover, HLP-1 could significantly improve the proliferation and neutral red phagocytosis of RAW264.7. Besides, HLP-1 could stimulate the production of nitric oxide (NO), ROS, tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6). HLP-1 induced macrophage activation via NF-κB signal pathway. These findings indicated that HLP-1 was a potential immune enhancement agent applied in functional foods.


Asunto(s)
Ascomicetos , Mananos , Animales , Ascomicetos/metabolismo , Interleucina-6/metabolismo , Activación de Macrófagos , Mananos/química , Mananos/farmacología , Ratones , Polisacáridos/química , Células RAW 264.7
3.
Front Immunol ; 12: 697071, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34745088

RESUMEN

Background: High mobility group box 1 (HMGB1) causes microvascular endothelial cell barrier dysfunction during acute lung injury (ALI) in sepsis, but the mechanisms have not been well understood. We studied the roles of RAGE and Rho kinase 1 (ROCK1) in HMGB1-induced human pulmonary endothelial barrier disruption. Methods: In the present study, the recombinant human high mobility group box 1 (rhHMGB1) was used to stimulate human pulmonary microvascular endothelial cells (HPMECs). The endothelial cell (EC) barrier permeability was examined by detecting FITC-dextran flux. CCK-8 assay was used to detect cell viability under rhHMGB1 treatments. The expression of related molecules involved in RhoA/ROCK1 pathway, phosphorylation of myosin light chain (MLC), F-actin, VE-cadherin and ZO-1 of different treated groups were measured by pull-down assay, western blot and immunofluorescence. Furthermore, we studied the effects of Rho kinase inhibitor (Y-27632), ROCK1/2 siRNA, RAGE-specific blocker (FPS-ZM1) and RAGE siRNA on endothelial barrier properties to elucidate the related mechanisms. Results: In the present study, we demonstrated that rhHMGB1 induced EC barrier hyperpermeability in a dose-dependent and time-dependent manner by measuring FITC-dextran flux, a reflection of the loss of EC barrier integrity. Moreover, rhHMGB1 induced a dose-dependent and time-dependent increases in paracellular gap formation accompanied by the development of stress fiber rearrangement and disruption of VE-cadherin and ZO-1, a phenotypic change related to increased endothelial contractility and endothelial barrier permeability. Using inhibitors and siRNAs directed against RAGE and ROCK1/2, we systematically determined that RAGE mediated the rhHMGB1-induced stress fiber reorganization via RhoA/ROCK1 signaling activation and the subsequent MLC phosphorylation in ECs. Conclusion: HMGB1 is capable of disrupting the endothelial barrier integrity. This study demonstrates that HMGB1 activates RhoA/ROCK1 pathway via RAGE, which phosphorylates MLC inducing stress fiber formation at short time, and HMGB1/RAGE reduces AJ/TJ expression at long term independently of RhoA/ROCK1 signaling pathway.


Asunto(s)
Permeabilidad Capilar/fisiología , Células Endoteliales/metabolismo , Proteína HMGB1/fisiología , Receptor para Productos Finales de Glicación Avanzada/fisiología , Quinasas Asociadas a rho/fisiología , Células Cultivadas , Humanos , Cadenas Ligeras de Miosina/fisiología , Transducción de Señal/fisiología
4.
Trials ; 22(1): 719, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34666815

RESUMEN

BACKGROUND: Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, diarrhea or constipation, and changes in defecation patterns. No organic disease is found to explain these symptoms by routine clinical examination. This study aims to investigate the efficacy and safety of acupuncture therapy for IBS patients compared with those of conventional treatments. We also aim to identify the optimal acupoint combination recommended for IBS and to clarify the clinical advantage of the "multiacupoint co-effect and synergistic effect." METHODS AND ANALYSIS: A total of 204 eligible patients who meet the Rome IV criteria for IBS will be randomly stratified into acupuncture group A, acupuncture group B, or the control group in a 1:1:1 ratio with a central web-based randomization system. The prespecified acupoints used in the control group will include bilateral Tianshu (ST25), Shangjuxu (ST37), Neiguan (PC6), and Zusanli (ST36). The prespecified acupoints used in experimental group A will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Neiguan (PC6). The prespecified acupoints used in experimental group B will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Zusanli (ST36). Each patient will receive 12 acupuncture treatments over 4 weeks and will be followed up for 4 weeks. The primary outcome is the IBS-Symptom Severity Scale (IBS-SSS) score. The secondary outcomes include the Bristol Stool Form Scale (BSFS), Work and Social Adjustment Score (WSAS), IBS-Quality of Life (IBS-QOL), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS) scores. Both the primary outcome and the secondary outcome measures will be collected at baseline, at 2 and 4 weeks during the intervention, and at 6 weeks and 8 weeks after the intervention. ETHICS AND DISSEMINATION: The entire project has been approved by the ethics committee of the Beijing University of Chinese Medicine (2020BZYLL0903). DISCUSSION: This is a multicenter randomized controlled trial for IBS in China. The findings may shed light on the efficacy of acupuncture as an alternative to conventional IBS treatment. The results of the trial will be disseminated in peer-reviewed publications. TRIAL REGISTRATION: Chinese Clinical Trials Register ChiCTR2000041215 . First registered on 12 December 2020. http://www.chictr.org.cn/ .


Asunto(s)
Terapia por Acupuntura , Síndrome del Colon Irritable , Puntos de Acupuntura , Terapia por Acupuntura/efectos adversos , Diarrea , Humanos , Síndrome del Colon Irritable/diagnóstico , Síndrome del Colon Irritable/terapia , Estudios Multicéntricos como Asunto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
5.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4287-4292, 2021 Aug.
Artículo en Chino | MEDLINE | ID: mdl-34467743

RESUMEN

The formulation of expert consensus on clinical application of Chinese patent medicines, in means of exploring the effective combination of experience and evidence to form a research method in line with the characteristics of Chinese patent medicines, is an important transitional stage for clinical researches on Chinese patent medicines. Pre-searching is a new step in the formulation of expert consensus on clinical application of Chinese patent medicines. Before steps of interview and investigation on clinical application, pre-searching is conducted to collect publications and literature on certain variety and similar Chinese patent medicines; the publications on related medical classics and formulas of this variety; the recommendation condition of this variety in clinical practice guidelines and expert consensus; and the medication regimens recommended in disease-specific guidelines. Pre-searching is designed to know about the advantages of certain variety of Chinese patent medicine as well as its potential problems recorded in the literature, which is helpful to find out the clinical positioning of Chinese patent medicines, develop reasonable clinical questions and provide ideas for formal literature searching. However, it is not the direct basis for developing clinical questions. Moreover, interviews and investigations are still needed to further clarify the clinical positioning of Chinese patent medicines and develop reasonable questions. This paper took expert consensus on clinical application of Yanshen Jianwei Capsules as an example to introduce the pre-searching process and methods used during formulation of expert consensus on clinical application of Chinese patent medicines, and to further discuss the role of pre-searching to facilitate the formulation of clinical questions on selection of participants, interventions, controls and outcomes.


Asunto(s)
Medicamentos Herbarios Chinos , Medicamentos sin Prescripción , Cápsulas , China , Consenso , Humanos , Medicina Tradicional China
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117675, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31670047

RESUMEN

By modifying the 10-butyl-2-methoxy-10H-phenothiazine-3-carbaldehyde with malonontrile group, a new fluorescent sensor PBM for selective detection of hydrazine in ratiometric mode has been developed. Probe PBM owned the advantages of quick response (10 min), remarkable Stokes shift (168 nm for PBM, 161 nm for PBM-NH2), excellent selectivity, high sensitivity (detection limit of 63.2 nM was obtained from in vitro experiment), profound ratiometric change (82-fold) and low cytotoxicity in response to hydrazine. Additionally, it could be utilized to monitor hydrazine in gas state with various concentrations through vivid color changes and imaged hydrazine in living MCF-7 cells with excellent performance.


Asunto(s)
Colorantes Fluorescentes/química , Hidrazinas/química , Imagenología Tridimensional , Fenómenos Ópticos , Fenotiazinas/química , Supervivencia Celular , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Factores de Tiempo
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(3): 362-366, 2019 May.
Artículo en Chino | MEDLINE | ID: mdl-31631604

RESUMEN

OBJECTIVE: To determine the association between daily particulate matter 2.5 (PM 2.5) mass and emergency calls for help with respiratory diseases. METHODS: Semi-parametric generalized additive model was established to determine the association between daily PM 2.5 and emergency calls for help with respiratory diseases in 2017 in Chengdu, after adjustments for time trend and variations in the days of the week and weather conditions. RESULTS: In 2017, a total of 9 309 emergency calls for help with respiratory diseases were recorded in Chengdu: on average 26 calls a day. Over the year, Chengdu reported a mean PM 2.5 mass concentration of 53.6 µg/m 3, an average temperature of 16.6 ℃, and an average relative humidity of 81.2%. The single pollutant model with lag time effect showed that a 10 µg/m 3 increase in PM 2.5 was associated with an increase of 1.26% (95% confidence interval ( CI) 0.56%-1.97%) emergency calls for help with respiratory diseases. The exposure-response was almost in a direct line. The dual pollutant model found that O 3 8-hour sliding average (O 3-8 h) enhanced the effect of PM 2.5 on emergency calls for help with respiratory diseases. CONCLUSION: Outdoor PM 2.5 is a significant predictor of emergency calls for help with respiratory diseases in Chengdu.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Servicios Médicos de Urgencia/estadística & datos numéricos , Material Particulado/efectos adversos , Enfermedades Respiratorias/epidemiología , China , Humanos , Temperatura
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(1): 124-129, 2017 Jan 20.
Artículo en Chino | MEDLINE | ID: mdl-28109112

RESUMEN

OBJECTIVE: To investigate performance of a biotinylated imaging probe 3a for targeted imaging of breast cancer cells. METHODS: Ultraviolet absorption spectrum and fluorescence spectrum were employed to analyze the spectral characteristics of 3a. The fluorescence spectrums of 3a treated with different concentrations of glutathione (GSH) were obtained to determine the sensibility of 3a to GSH. Flow cytometry was used to determine the cellular uptake of 3a by MCF-7 cells, MDA-MB-231 cells and Hs 578Bst cells in the presence or absence of biotin, and the imaging performance of 3a in the 3 cell lines was assessed under an inverted fluorescent microscope. The toxicity of 3a to the cells was evaluated using MTT method. RESULTS: 3a showed the strongest absorption peak at 510 nm, and its fluorescence emission signal was the strongest at 544 nm. As the concentration of GSH increased (0-6 mmol/L), 3a exhibited an increasing fluorescence signal at 544 nm. The cellular uptake of 3a was markedly higher in MDA-MB-231 cells and MCF-7 cells than in Hs 578Bst cells. The imaging studies showed that 3a had a good breast cancer cell-targeting property and produced clear images under fluorescent microscope. MTT assay demonstrated no obvious toxicity of 3a in Hs 578Bst cells even at the concentration of 20 µmol/L, but MCF-7 cells and MDA-MB-231 cells exposed to 2-20 µmol/L 3a showed a lowered cell viability. CONCLUSION: 3a is capable of targeted imaging of breast cancer cells mediated by biotin. 3a at the concentration of 2-20 µmol/L has minimal cytotoxicity to normal breast cells but can lower the viability of breast cancer cells.


Asunto(s)
Biotina/análogos & derivados , Biotina/farmacocinética , Neoplasias de la Mama/metabolismo , Glutatión/metabolismo , Xantonas/farmacocinética , Biotinilación , Neoplasias de la Mama/diagnóstico por imagen , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Microscopía Fluorescente , Espectrometría de Fluorescencia/métodos , Rayos Ultravioleta
9.
Sci Rep ; 6: 25595, 2016 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-27157290

RESUMEN

A series of three remarkable complexes [PMo12O40]@[Cu6O(TZI)3(H2O)9]4·OH·31H2O (H3TZI = 5-tetrazolylisophthalic acid; denoted as HLJU-1, HLJU = Heilongjiang University), [SiMo12O40]@[Cu6O(TZI)3(H2O)9]4·32H2O (denoted as HLJU-2), and [PW12O40]@[Cu6O(TZI)3(H2O)6]4·OH·31H2O (denoted as HLJU-3) have been isolated by using simple one-step solvothermal reaction of copper chloride, 5-tetrazolylisophthalic acid (H3TZI), and various Keggin-type polyoxometalates (POMs), respectively. Crystal analysis of HLJU 1-3 reveals that Keggin-type polyoxoanions have been fitted snuggly in the cages of rht-MOF-1 (MOF: metal-organic framework) with large cell volume in a range of 87968-88800 Å(3) and large pore volume of about 68%. HLJU 1-3 exhibit unique catalytic selectivity and reactivity in the oxidation of alkylbenzene with environmental benign oxidant under mild condition in aqueous phase as well as the uptake capacity towards organic pollutants in aqueous solution.

10.
Dalton Trans ; 45(4): 1657-67, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26693646

RESUMEN

To investigate the influence of POM species, temperature and counterions on the structures of POM-MOFs containing Cu-tda second building units (SBUs), six new complexes with various dimensionalities, e.g. three dimensional (3D) [Cu(H2tda)(H2O)2]4[SiW12O40]·12H2O (), two dimensional (2D) [Cu2(H2tda)2(H2O)3]·[Cu(H2tda)(H2O)2]·[PMo12O40]·5H2O (), H-bond 2D [Cu(H2tda)(H2O)2]3·[PMo12O40]·[Cu(Htda)(H2O)3]·8H2O (), one dimensional (1D) [Cu2(H2tda)2(H2O)4]2·[Cu2(tda)2(H2O)4]·[HPW12O40]·5H2O (), 1D [Cu2(H2tda)2(H2O)4][SiW12O40]·(TMA)2·3H2O (), and zero dimensional (0D) [Cu(H2tda)(H2O)3][SiW12O40]·(TMA)3·H2O (), were isolated depending on the reaction conditions. It is observed that the POM species, temperature and counterions exhibit an essential effect on the structures, which results in the formation of various dimensional POM-MOF complexes . In addition, photocatalytic degradation of RhB by complexes , and under UV irradiation was also investigated.

11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(8): 929-932, 2016 08.
Artículo en Chino | MEDLINE | ID: mdl-30640986

RESUMEN

Objective To observe distribution laws and features of syndrome types of Chinese medicine (CM) in hyperlipidemia patients of Han, Uyghur, Kazakh nationalities in Xinjiang Uyghur Auton- omous Region. Methods Using cluster random sampling, 1 410 hyperlipidemia patients (18 -70 years old ) were recruited from Urumqi, Turpan, Altay, Ili, Aksu, Hetian in Xinjiang Uyghur Autonomous Re- gion. The general condition, susceptible factors, classification of blood lipids, complications, syndromes of CM, tongue figure, etc. clinical data were investigated using self-formulated Epidemiological Investiga- tion Questionnaire on Susceptible Factors in Different Nationalities of Hyperlipemia Patients in Xinjiang (abbreviated as Questionnaire thereafter). Factor analysis and cluster analysis were performed. Results Cronbach's coefficient for the 54 syndrome items in Questionnaire was 0.891, Kaiser-Meyer-Olkin (KMO) 0. 897, Sig <0.05 in Bartlett's sphericity test. Seventeen common factors were obtained using principal component analysis (PCA). Totally 54 common symptoms of hyperlipidemia were screened, which were then divided into 17 groups with 1 -6 symptoms in each group. F4 (soreness and weakness of waist and knees, sour pain in joints and muscles, body numbness, heavy body sensation, cold limbs), F5 (frequent and clear nocturia, dysuria,-dribble of urine, frequent urination at night), F10 (thirsty, no desire for water, tastelessness, hydroadipsia) , F12 (a white complexion with puffiness, hid- ing fever, hypoactive sexual desire) , and F17 (enuresis) were merged as Shen yang deficiency (SYD) ; F2 (fatigue, drowsiness, depression, spiritlessness, fatigue and disinclination to talk) and F15 (poor ap- petite) were merged as Pi-qi deficiency (PQD) ; F3 (dry mouth and dry pharynx, thirsty, propensity for water, bitter mouth, greasy mouth, stingy mouth, irritability and upset) and F16 (dark red tongue proper, greasy tongue fur) were merged as damp-heat trapped in Pi (DHTP). Results of cluster analysis showed that Pi-Shen deficiency (PSD) was most often seen in hyperlipidemia, and main syndrome types were sequenced from high to low as Pi-Shen deficiency type (46. 2%, 652/1 410) , blockage of cardiac vessels type ( 31. 1% , 438/1 410 ), phlegm and blood stasis internal resistance type ( 13. 3% , 187/1 410), Pi-deficiency induced damp abundance type (8. 3%, 123/1 410), Gan-Shen yin deficiency type (0. 7%, 10/1 410). Conclusions Deficiency syndrome was dominant in hyperlipidemia patients of Xinjiang Uyghur Autonomous Region. Phlegm turbidity, damp heat, and etc. were often complicated. The complex situation was manifested to be involved in multiple organs, qi-blood-fluid mixed disease.


Asunto(s)
Hiperlipidemias , Medicina Tradicional China , Adolescente , Adulto , Anciano , China , Humanos , Hiperlipidemias/diagnóstico , Hiperlipidemias/terapia , Persona de Mediana Edad , Síndrome , Deficiencia Yang , Deficiencia Yin , Adulto Joven
12.
Chem Asian J ; 11(4): 555-60, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26663517

RESUMEN

A series of five l-di-p-toluoyl-tartaric acid (l-DTTA) lanthanide coordination polymers, namely {[Ln4 K(4) L6 (H2O)x ]⋅yH2 O}n , [Ln=Dy (1), x=24, y=12; Ln=Ho (2), x=23, y=12; Ln=Er (3), x=24, y=12; Ln=Yb (4), x=24, y=11; Ln=Lu (5), x=24, y=12] have been isolated by simple reactions of H2L (H2 L= L-DTTA) with LnCl3 ⋅6 H2O at ambient temperature. X-ray crystallographic analysis reveals that complexes 1-5 feature two-dimensional (2D) network structures in which the Ln(3+) ions are bridged by carboxylate groups of ligands in two unique coordinated modes. Luminescent spectra demonstrate that complex 1 realizes single-component white-light emission, while complexes 2-4 exhibit a characteristic near-infrared (NIR) luminescence in the solid state at room temperature.

13.
Opt Lett ; 40(9): 1888-91, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25927740

RESUMEN

By exploiting the polymer/silica hybrid and the air trench waveguide structures, we demonstrate a new type of low-power consuming and high-speed thermal-optic (TO) switch. Such a design provides an effective means to shorten the switching time of the TO switches, as well as to reduce the power consumption at the same time. This TO switch operated with less than 150 µs of switching time via a polymer/silica hybrid waveguide structure. Meanwhile, the power consumption was reduced to be 3.4 mW by introducing the air trench structure.

14.
Dalton Trans ; 44(10): 4640-7, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25661972

RESUMEN

A series of L-di-2-thenoyltartaric acid lanthanide coordination polymers, namely, {[La2L3(CH3OH)6(H2O)]·CH3OH·H2O}n (1), {[Ln2L3(CH3OH)x(H2O)6−x]·aCH3OH·bH2O}n, [Ln = Eu (2), x = 2, a = 0.5, b = 0.25; Ln = Gd (3), x = 3, a = 1, b = 0; Ln = Tb (4), x = 2, a = 1, b = 0], {[(Eu0.037Tb0.963)2L3(CH3OH)2(H2O)4]·CH3OH·2.75H2O}n (5), {[(Eu0.051Tb0.406La0.543)2L3(CH3OH)2(H2O)4]·0.5CH3OH·2H2O}n (6), and {[(Eu0.068Tb0.363Gd0.569)2L3(CH3OH)3(H2O)3]·CH3OH·H2O}n (7), have been synthesized using facile reactions of H2L (H2L = L-di-2-thenoyltartaric acid) with LnCl3·6H2O under ambient temperature. X-ray crystallographic analysis reveals that complexes 1­4 are isostructural, featuring one-dimensional (1D) ladder-like chain structures, in which the Ln(3+) ions are bridged by the carboxylate groups of the ligands. The luminescent spectra in the solid state at room temperature reveal that complexes 2 and 4 exhibit the characteristic red and green luminescence of Eu(3+) and Tb(3+) ions, respectively, whereas complexes 1 and 3 display the blue emission of the ligand with a broad band centered at 422 nm. Notably, the mixed-lanthanide coordination polymers 5­7 exhibit color-tunable luminescence from yellow and white to blue upon variation of the excitation wavelength. It realizes color-tunable and white-light emission in 1D carboxylic acid mixed-lanthanide coordination polymers.

15.
Inorg Chem ; 54(1): 221-8, 2015 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-25495352

RESUMEN

A series of rigid hexadentate salen-type (H2L) ytterbium complexes, namely, [Yb2L3(CH3OH)]·3CH3CN (1), [Yb2LL'L″(CH3OH)(H2O)2](ClO4)2·CH3OH·H2O (2), [Yb2L(OAc)4(CH3OH)2]·2CH3OH (3), and {[Yb2L(OAc)4]·3H2O}n (4) (H2L = N,N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine, HL' = 2-(2'-hydroxy-3'-methyloxy-phenyl)benzimidazole and HL" = 3-methoxysalicylaldehyde) have been synthesized by reactions of H2L with multifarious Yb(3+) salts. X-ray crystallographic analyses demonstrate that complex 1 is of a triple-decker sandwich-type Yb2L3 structure with a ratio of H2L/Yb = 3:2, 2 and 3 possess the unique Yb2 core with a ratio of H2L/Yb = 2:2 and 1:2, respectively, 4 exhibits one dimensional coordination polymers in which the polymeric structures are formed by acetate (OAc(-)) groups. All complexes 1-4 exhibit near-IR luminescence, which can be rationalized on the basis of the disparate structural effects. The magnetic analysis unveils that all complexes 1-4 are of field-induced single-molecule magnet behavior with the energy barriers (Ueff/kB) of 14.5, 2.0, 9.5, and 2.4 K at 3 kOe direct current fields, respectively.

16.
Dalton Trans ; 44(4): 1948-54, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25492257

RESUMEN

Two polyoxometalate-based coordination polymers (POMCPs) constructed form Keggin POMs and Ag(+) with pyttz were synthesized: [Ag4(H2pyttz-I)(H2pyttz-II)(Hpyttz-II)][HSiW12O40]·4H2O (1) and [Ag4(H2pyttz-II)(Hpyttz-II)2][H2SiW12O40]·3H2O (2) (H2pyttz-I = 3-(pyrid-2-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl; H2pyttz-II = 3-(pyrid-4-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl). Both compounds have similar building units, similar stick-like units and similar 1D inorganic chains, but finally form the different motifs of tunnels (tunnel A in 1 and tunnel A&B in 2). By careful inspection of the structures of 1 and 2, it is believed that the isomerous pyttz molecules can precisely refine the structure of porous POMCPs without changing the underlying framework, which favors the study of the structure-activity relationship of POMCPs. Furthermore, the results of the photocatalytic activities show that compound 2 exhibits higher photocatalytic activity than that of compound 1, which is consistent with their structural characterization.


Asunto(s)
Complejos de Coordinación/química , Plata/química , Compuestos de Tungsteno/química , Catálisis , Complejos de Coordinación/efectos de la radiación , Estructura Molecular , Porosidad , Difracción de Polvo , Rodaminas/química , Plata/efectos de la radiación , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos de Tungsteno/efectos de la radiación , Rayos Ultravioleta , Contaminantes Químicos del Agua/química , Difracción de Rayos X
17.
Huan Jing Ke Xue ; 35(9): 3287-92, 2014 Sep.
Artículo en Chino | MEDLINE | ID: mdl-25518643

RESUMEN

Electrical low pressure impactor (ELPI) was used to online analyze the PM2.5 particle size and mass concentration distribution in the trapping field and ore tank of blast furnace iron-making plant. Results showed that the grain number concentration of PM2.5 in trapping field after dust removal was in the range of 10(5)-10(6)cm-3 , and the particle size was mainly below 0. 1 µm. While the grain number concentration of the PM2.5 in ore tank after dust removal was in the range of 10(4)-10(5) cm-3, the particle size was mainly below 1.0 µm, and the mass concentration distribution showed a single peak. The micro-morphology of PM2.5 monomer was mainly divided into two categories, spherical particles and irregular aggregates. Chemical composition analysis indicated that the concentrations of water soluble SO(2-)(4) , K+ , Ca2+ were higher than other ions in PM2.5, with the percentage of 10. 32% -28.55% , 10. 36% -12. 15% , 3.97% -15. 4% , respectively. The major elements was Fe, Si, Al, with 16. 8% -31. 62% , 2. 24% -8.76% , 1.24% -5. 89% of total mass, respectively; organic carbon and elementary carbon were 2. 7% -4. 6% and 0. 8% -1. 3% , respectively. The emission factors of PM2.5 in trapping field and in ore tank after dust removal were ranged from 0.045 to 0.085 kg t(-1) and 0.042 to 0.071 kg t-1, respectively.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Industria Procesadora y de Extracción , Hierro , Material Particulado/análisis , Carbono/análisis , Polvo/análisis , Tamaño de la Partícula , Agua
18.
Opt Express ; 22(9): 11119-28, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24921810

RESUMEN

In this paper, a low-power 1 × 2 polymeric thermo-optic switch operating at the polymer optical fiber low-loss window of 650 nm was studied. The characteristic parameters of the switch were carefully designed and simulated. The fabrication was done by using standard semiconductor fabrication techniques such as spin-coating, photolithography, and dry etching. The device was fabricated based on poly(methyl methacrylate) (PMMA)-based materials with the Mach-Zehnder interferometer (MZI) structure. The device shows an extinction ratio of over 23.4 dB at 650 nm with a very low-power consumption of 5.3 mW. The measured switching rise time and fall time are 464.4 and 448.0 µs, respectively.

19.
Dalton Trans ; 42(21): 7803-9, 2013 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-23558903

RESUMEN

A new hybrid compound, Na[Ag6(pyttz)2(H2O)][PMo12O40] (pyttz = 3-(pyrid-3-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), has been hydrothermally synthesized and structurally characterized by routine techniques. X-ray diffraction analysis reveals that the title compound is constructed by the 2D Ag-pyttz coordination polymer and 3D Ag-POM architecture with helix. A fascinating structural feature is the assembling fashion of the right- and left-helical chain, namely, the helical chains with different orientations are intertwined with each other forming intertwined double helical layers along the c-axis, and the identical left- or right-handed helical chains are fused together in a hand-by-hand mode generating another homological helical layer along the a-axis. As a result, these helical layers intersect each other obtaining an unprecedented 3D POM-Ag inorganic architecture. Note that the 3D framework with a helix constructed by POMs and metal ions has never been observed up to date. Additionally, its photocatalytic degradation of RhB was also investigated.


Asunto(s)
Compuestos Organometálicos/química , Plata/química , Compuestos de Tungsteno/química , Catálisis , Cristalografía por Rayos X , Modelos Moleculares , Compuestos Organometálicos/síntesis química , Fotólisis , Rodaminas/química , Triazoles/síntesis química , Triazoles/química , Compuestos de Tungsteno/síntesis química
20.
Asian Pac J Cancer Prev ; 14(1): 523-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23534787

RESUMEN

BACKGROUND: The possibility that electromagnetic fields (EMF) exposure may increase male breast cancer risk has been discussed for a long time. However, arguments have been presented that studies limited by poor quality could have led to statistically significant results by chance or bias. Moreover, data fo the last 10 years have not been systematically summarized. METHODS AND RESULTS: To confirm any possible association, a meta-analysis was performed by a systematic search strategy. Totals of 7 case-control and 11 cohort studies was identified and pooled ORs with 95% CIs were used as the principal outcome measures. Data from these studies were extracted with a standard meta-analysis procedure and grouped in relation to study design, cut-off point, exposure assessment method, adjustment and exposure model. A statistical significant increased risk of male breast cancer with EMF exposure was defined (pooled ORs = 1.32, 95% CI = 1.14 -1.52, P < 0.001), and subgroup analyses also showed similar results. CONCLUSIONS: This meta-analysis suggests that EMF exposure may be associated with the increase risk of male breast cancer despite the arguments raised.


Asunto(s)
Neoplasias de la Mama Masculina/etiología , Campos Electromagnéticos/efectos adversos , Exposición Profesional/efectos adversos , Estudios de Casos y Controles , Estudios de Cohortes , Intervalos de Confianza , Humanos , Masculino , Oportunidad Relativa
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