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1.
Inorg Chem ; 58(22): 15344-15353, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31697488

RESUMO

Internal polarized electric field is found to be an effective and available strategy to separate photogenerated electron-hole pairs. By this method, the efficiency of photocatalytic reactions can be obviously enhanced. Here, the layered compound of BiOIO3 with spontaneous polarization was synthesized by a simple hydrothermal method. Taking another bismuth compound BiOI as a counterpart, which has a similar layered structure, the spontaneous polarization effects of BiOIO3 were analyzed and confirmed. The photocatalytic activity of BiOIO3 and BiOI were evaluated by the degradation of methyl orange. Methyl orange was almost completely photocatalytically decomposed by BiOIO3 and BiOI in 40 and 90 min, respectively. The separation and transfer behaviors of photogenerated electron-hole pairs were investigated by a series of photoelectrochemical characterizations. It is further proved the separation and transmission efficiency of BiOIO3 are higher than those of BiOI. According to the results of density of theory calculations, the internal polarized electric field in BiOIO3 is ascribed to the spatial asymmetry of the IO3 group, which is estimated to ∼1.5 × 1010 V/m. Under the action of this internal polarized electric field, the photogenerated electrons and holes would transfer along opposite directions, i.e., photogenerated electrons and holes respectively gather at the Bi/I side and O side. Additionally, superoxide radicals (•O2-) and holes (h+) are produced during the degradation process, which are responsible for the high visible-light photocatalytic activity. Finally, the cyclic degradation test proves that its photocatalytic performance has long-term stability. Therefore, BiOIO3 polar material can be used as one of the alternative materials for efficient photocatalytic reaction.

2.
Zhonghua Er Ke Za Zhi ; 48(7): 492-6, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21055084

RESUMO

OBJECTIVE: To introduce the Ages and Stages Questionnaire (ASQ) to China, we created ASQ-Chinese (ASQ-C) and carried out studies of its norm and the psychometrical properties in Shanghai children aged 3-66 months in collaboration with the author of the ASQ with the permissions from the publisher. METHOD: The 19 ASQ intervals were translated into Chinese, to make the ASQ-C culturally relevant, and back translated into English. The project used a stratified cluster sampling method and recruited children aged 3 - 66 months with respect to demographic characteristics that were representative of Shanghai census data, and excluded the children whose mother tongue was not Chinese and/or diagnosed with disabilities by the authoritative hospitals in Shanghai. Parents/caregivers of the 8472 children either independently completed the age-appropriate ASQ-Cs or completed with help from the researchers for the normative samples. Among them, professionals completed the age-appropriate ASQ-C again for 519 children within six days after the parents/caregivers completed the ASQ-C for inter-rater reliability. In terms of test-retest reliability, 651 parents completed another age-appropriate questionnaires within a 10- to 23-day interval. For concurrent validity, BSIDII were administered with 255 children from 6, 12, 18, 24, and 30-month ASQ-C age intervals. The cutoffs of the ASQ-C and the BSIDII were all set at the two standard deviations below the means. The statistical analysis was carried out using SPSS 13.0. RESULT: The ASQ-Cs were independently completed by 85.25% of the parents/caregivers; the percentage of gender, family income and region of residence were similar to the Shanghai population census conducted in the recent years. Two standard deviations below the means were used as the cutoff scores of the ASQ-Cs across the age intervals. In terms of internal consistency of the ASQ-C, Cronbach standardized alpha was 0.77. The Pearson correlation coefficient between the ASQ-C total scores of the two testers was 0.84 (P < 0.0001). The Pearson correlation coefficient between the ASQ-C total scores of the two tests was 0.82 (P < 0.0001). The percentage of the agreement between the ASQ-C and the BSID II was 84.31%, the sensitivity of ASQ-C was 85.00%, and the specificity of ASQ-C was 84.26%. CONCLUSION: It is practicable that the ASQ-C can be completed by the parents/caregivers of Shanghai children. ASQ-C has solid psychometric properties and is worthy of further research and introduction to China.


Assuntos
Modelos Psicológicos , Psicometria/estatística & dados numéricos , Inquéritos e Questionários , Fatores Etários , Desenvolvimento Infantil , Pré-Escolar , China , Humanos , Lactente
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 44(4): 334-8, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20654147

RESUMO

OBJECTIVE: To assess thyroid disruption induced by sodium pentachlorophenol (PCP) using Organization for Economic Co-operation and Development (OECD) recommended TG 407 method. METHODS: A total of 30 specific pathogen free (SPF) SD adult male and female rats were randomly divided into 3 groups, and treated with water, 0.33 and 30 mg x kg(-1)x d(-1) of PCP-Na by oral gavage for consecutive 28 days, respectively. After final treatment, histological changes of thyroid were observed by hematoxylin-eosin stain, and the levels of thyroid hormones (total thyroxine (TT(4)), free thyroxine (FT(4)), total triiodothyronine (TT(3)), and free triiodothyronine (FT(3))) were determined by radioimmunoassay. The expression levels of thyroid receptors (TRalpha and TRbeta) mRNA and deiodinases (DioI, DioII and DioIII) mRNA in liver were analyzed by RT-PCR. RESULTS: In high dose group, liver weight coefficient of male and female rats were (4.82 +/- 0.42)% and (4.99 +/- 0.17)%, increased by 36.2% (t = 7.338, P < 0.01) and 41.8% (t = 8.955, P < 0.01), compared to control group ((3.54 +/- 0.14)%, (3.52 +/- 0.19)%), respectively, while the significant changes of kidney or thyroid weight were not observed. In high dose group, the levels of TT(4) and FT(4) in serum of male rats were (64.95 +/- 7.16) nmol/L and (8.16 +/- 2.29) pmol/L, and decreased by 26.6% (t = -3.999, P < 0.01) and 42.3% (t = -4.112, P < 0.01) compared to control group ((88.48 +/- 6.99) nmol/L, (14.13 +/- 1.68) pmol/L). In the same group, FT(4) in serum of female rats was (4.94 +/- 0.89) pmol/L, decreased by 55.5% (t = -3.380, P = 0.012) compared to control group ((11.10 +/- 3.40) pmol/L) and TT(3) and FT(3) in serum of female rats were (1.92 +/- 0.24) nmol/L and (3.05 +/- 0.79) pmol/L, increased by 74.5% (t = 5.263, P < 0.01) and 55.6% (t = 3.495, P < 0.01) compared to control group ((1.10 +/- 0.23) nmol/L, (1.96 +/- 0.32) pmol/L), respectively. PCP-Na didn't affect the expression levels of TRalpha, TRbeta, DioIII mRNA in high dose group, while DioII expression of male rats (0.209 +/- 0.017) down-regulated by 79.2% (t = -5.426, P < 0.01) compared to control group (1.006 +/- 0.137), and DioI expression of female rats (1.844 +/- 0.189) up-regulated by 66.6% (t = 4.359, P < 0.01) compared to control group (1.005 +/- 0.083), indicating DioI and DioII poss different sensitivity to adverse effects induced by PCP-Na between male and female rats. The histopathological results showed that PCP-Na could give rise to hyperplasia of the follicular epithelium cells, and the depletion of colloid. There were no significant changes in serum THs levels and expression of TRalpha, TRbeta, DioI-IIImRNA in low dose group. However, sporadic lymphocytic infiltration, follicles amplification in part and slightly increased in thickness of follicular cells were observed in this group. CONCLUSION: PCP is a kind of thyroid disrupting chemical.


Assuntos
Fígado/patologia , Pentaclorofenol/toxicidade , Glândula Tireoide/efeitos dos fármacos , Animais , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Hormônios Tireóideos/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
4.
Zhonghua Er Ke Za Zhi ; 48(11): 824-8, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21215025

RESUMO

OBJECTIVE: To study the validity and accuracy of differing cutoff scores of the Ages and Stages Questionnaires-Chinese (ASQ-C) for screening infants and toddlers in comparison with the gold standard, Bayley Scale of Infant Development, Second Edition (BSID II). METHOD: The 269 samples were enrolled from the normative children, aged 3 - 31 months, of the ASQ-C in Shanghai. The age-appropriate ASQ-Cs were completed by parents/caregivers and the BSIDIIwas administered by professionals. The cutoff scores of -2 standard deviation (s), -1.5 s, and -s for the ASQ-C were examined against BSID II with the cutoff scores set at -2 s as the standard of developmental delay, -s as the standard of suspected developmental delay and developmental delay respectively. Agreement between the classifications of the ASQ-C (i.e., typical, suspected, delay) was compared with the classification of the BSID II (typical, suspected, delay), sensitivity, specificity, Youden Index and area under ROC curve of ASQ-C were examined. The statistical analysis was carried out using SPSS 13.0. RESULT: When the cutoff score for BSID II was -2 s, the -2 s cutoff score for ASQ-C exhibited the following properties: the highest agreement of 83.64%, the sensitivity and specificity both above 80% being respectively 88.46% and 83.13%, the highest Youden Index of 0.72 and the largest area of 0.86 under ROC curve. The -1.5 s cutoff score for ASQ-C showed the following properties: 71.75% agreement, 100% sensitivity, 68.72% specificity, Youden Index = 0.69, the area under ROC curve = 0.84. The -s cutoff score for ASQ-C showed the following properties: the lowest agreement of 55.02%, 100% sensitivity, the lowest specificity of 50.21%, the lowest Youden Index of 0.50, and the smallest area of 0.75 under ROC curve. When the cutoff score for BSID II was set at -s, the -2 s for ASQ-C showed the following properties: the highest agreement of 85.87%, the lowest sensitivity of 68.57%, the highest specificity of 91.96%, Youden Index = 0.61, the smallest area = 0.77 under ROC curve. The -1.5 s for ASQ-C showed the following properties: the agreement of 80.67%, the sensitivity and specificity both above 70% being respectively 85.71% and 78.89%, the highest Youden Index of 0.65, the largest area of 0.82 under ROC. The -s cutoff score for ASQ-C showed the following properties: the lowest agreement of 68.40%, the highest sensitivity of 94.29%, the lowest specificity of 59.30%, the lowest Youden Index of 0.54, and the area under ROC curve = 0.80. When the cutoff score for BSID II was -1 to 2 s, the identifying percentages of the -2 s, -1.5 s and -s for the ASQ-C were 56.82%, 77.27% and 90.91%, respectively. CONCLUSION: For developmental delay identification, the -2 s cutoff score for ASQ-C produces the most robust validity and highest accuracy; for the identification of suspected developmental delay and developmental delay, the -1.5 s cutoff score for ASQ-C has the highest screening accuracy with appropriate sensitivity and specificity; for identifying the suspected developmental delay, the -s cutoff score for ASQ-C has the highest percentage of the identification. It is necessary to add 1 - 2 s to the ASQ-C's cutoff scores as the standard for screening suspected developmental delays.


Assuntos
Desenvolvimento Infantil , Programas de Rastreamento , Inquéritos e Questionários/normas , Pré-Escolar , Humanos , Lactente , Padrões de Referência , Sensibilidade e Especificidade
5.
Wei Sheng Yan Jiu ; 35(6): 703-5, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17290746

RESUMO

OBJECTIVE: To study the effects of grape seed proanthocyanidins extracts(GSPE) and its mechanism on early renal lesions of diabetic rats. METHODS: Diabetic rats induced by alloxan were given GSPE intragastrically for 6 weeks, then the antioxidative indexes and NO content, NOS activity in kidney and serum were measured, and the renal function indexes were tested as well. RESULTS: Compared with the diabetic group, the urinary protein/24h, levels of blood urea nitrogen(BUN)and serum creatinine(SCr), creatinine clearance rate(CCr) and the ratio of kidney weight/body weight were decreased, the SOD activity in kidney was raised while MDA content was fall in the GSPE group(high dose), and the differences were all significant. The NO content in the kidney and NOS activity in kidney and serum decreased in the GSPE (low dose)group, and there was significant difference when compared with diabetic group( P <0.05) . CONCLUSION: GSPE has the effect in protecting kidney of diabetic rats, the mechanism might be related with its action in increasing the renal antioxidative ability,decreasing the content of NO and the activity of NOS in kidney and serum.


Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Proantocianidinas/farmacologia , Vitis/química , Animais , Diabetes Mellitus Experimental/metabolismo , Rim/metabolismo , Testes de Função Renal , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Sementes/química
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