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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 862-868, 2024 Jun 06.
Article in Zh | MEDLINE | ID: mdl-38955734

ABSTRACT

Objective: To investigate the genotype and epidemiological characteristics of human metapneumovirus (HMPV) among hospitalized cases with acute respiratory infections (ARI) in children in Changchun City, Jilin Province, China. Methods: From June 2019 to June 2023, throat swabs of ARI inpatients in Changchun Children's Hospital were collected, and their epidemiological and clinical information were also collected. Quantitative reverse transcription-PCR was used to identify HMPV-positive cases, followed by the amplification of the G gene and genetic analysis in the HMPV-positive cases. Results: A total of 3 311 children hospitalized with ARI were included in this study. Their age ranged from 0 to 17 years old, and the M (Q1, Q3) of age was 2 (1, 3) years. About 1 811 (54.70%) cases were males. A total of 167 HMPV-positive cases were detected with a positive rate of 5.04%, of which 92.81% (155/167) were children under 5 years old. The positive rate of HMPV in 2019 was 6.37% (30/471), which dropped to the lowest in 2020 (2.31%, 10/432). The HMPV-positive rate was then rebounded in 2021 (4.70%, 60/1 277) and 2022 (4.56%, 21/461), which increased to 6.87% (46/670) in 2023. The difference in HMPV-positive rate among each year was statistically significant (P<0.05). The prevalence peak of HMPV varied in different years, showing either a unimodal or bimodal distribution in one year. A total of 79 HMPV G gene sequences were obtained, of which subtype A and subtype B accounted for 48.10% and 51.90%, respectively. All of the subtype A sequences were clarified as A2c duplicated variants, and subtype B was mainly B2 genotype. Besides, subtypes A and B were prevalent alone or co-circulated in different years, and there was a subtype replacement pattern in HMPV. Conclusion: The positive rate of HMPV in hospitalized ARI cases in children is significantly different from 2019 to 2023 in Changchun City. Notably, there are certain switch patterns of HMPV subtypes A and B in different years.


Subject(s)
Genotype , Metapneumovirus , Paramyxoviridae Infections , Respiratory Tract Infections , Humans , Metapneumovirus/genetics , Metapneumovirus/classification , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , Child , Child, Preschool , Infant , China/epidemiology , Male , Adolescent , Female , Paramyxoviridae Infections/epidemiology , Paramyxoviridae Infections/virology , Acute Disease , Hospitalization , Infant, Newborn , Phylogeny
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58: 1-8, 2024 Feb 23.
Article in Zh | MEDLINE | ID: mdl-38403281

ABSTRACT

Objective: To understand the infection status and molecular types of rhinovirus (RV) among cases of Acute Respiratory Infections (ARIs) in Luohe City, Henan Province, from 2017 to 2022. Methods: From October 2017 to June 2022, clinical and epidemiological data were collected from 2 270 cases of ARIs at Luohe Central Hospital in Henan Province. Throat swab specimens were obtained from these cases. Real-time quantitative polymerase chain reaction (qPCR) was used to screen for RV-positive specimens. Subsequently, the positive samples were subjected to nested reverse transcription polymerase chain reaction (nested RT-PCR) to amplify the full-length VP1 region. Using the MEGA software, along with 169 RV reference strains recommended by the International Committee on Taxonomy of Viruses, a phylogenetic tree was constructed to determine RV types. Results: Among the 2 270 cases of ARIs, there were 1 283 male cases (56.52%). The median age (Q1, Q3) was 3 (1, 6) years, with the population under 5 years old accounting for 68.59% (1 557/2 270). RV was detected in 137 cases (6.04%), of which 68 cases (49.64%) showed co-detection with other viruses, with the most common being co-detection with enterovirus, accounting for 14.60% (20/137). The RV detection rates in the age groups of 0~4 years, 5~14 years, 15~59 years, and≥60 years were 6.42% (100/1 557), 4.69% (21/448), 3.80% (6/158), and 9.35% (10/107), respectively, with no statistically significant differences (χ2=5.310, P=0.150). The overall detection rates of RV before (2017-2019) and during (2020-2022) the COVID-19 pandemic showed no statistically significant difference (χ2=1.823, P=0.177). A total of 109 VP1 sequences were obtained, including 62 types. Among them, RV-A, RV-B, and RV-C had 42, 3, and 17 types respectively. Conclusion: RV is one of the predominant pathogens in ARIs cases in Luohe City, Henan Province, from 2017 to 2022. Multiple types of RV co-circulate without any apparent dominant type.

3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58: 1-7, 2024 Feb 23.
Article in Zh | MEDLINE | ID: mdl-38403282

ABSTRACT

Objective: To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023. Methods: The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed. Results: A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M (Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant (P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age (P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion: Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(3): 378-385, 2023 Mar 06.
Article in Zh | MEDLINE | ID: mdl-36655353

ABSTRACT

Objective: To understand the infection status of Enterovirus (EV) in cases of acute respiratory infections (ARIs) in Luohe City, Henan Province from 2017 to 2021, and analyze the prevalence and type composition of EV in ARIs. Methods: From October 2017 to May 2021, pharyngeal swab samples were collected from 1 828 patients with ARIs in Luohe Central Hospital and the clinical epidemiological data of these cases were also collected. EV-positive samples were identified by Quantitative Real-time Polymerase Chain Reaction (qPCR). The 5'-untranslated region (5'UTR) was amplified by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). The results of 5'UTR region were initially typed by Enterovirus Genotyping Tool Version 1.0. Based on the typing results, the full-length of VP1 region was amplified by RT-PCR. The EV typing was identified again by VP1 region. Results: Among 1 828 cases of ARIs, 56.7% (1 036) were males. The median (Q1, Q3) age was about 3 (1, 5) years. Patients under 5 years old accounted for 71.6% (1 309 cases). Among all cases, a total of 71 EV-positive samples were identified by qPCR, with a detection rate of 3.88% (71/1 828). The EV detection rates for men and women were 3.28% (34/1 036) and 4.67% (37/792), without statistically significant differences (χ2=2.32, P=0.14). The EV detection rates for 2 to <6 years, 6 months to <2 years, 6 to <10 years, and <6 months were 6.29% (48/763), 3.00% (18/600), 2.52% (4/159), and 1.67% (1/60) (χ2=27.91, P<0.001). The EV detection rate was 0.92% (3/326) in autumn and winter of 2017. The EV detection rates were 1.18% (6/508), 2.47% (12/485) and 8.31% (34/409) in each year from 2018 to 2020, with an increasing trend year by year(χ2trend=29.76, P<0.001). The main prevalent seasons were summer and autumn. The detection rate in spring of 2021 was 4.00% (4/100). A total of 12 types were identified and classified as CVA2, CVA4, CVA5, CVA6, CVA10, CVB3, CVB5, E5, E11, E30, PV-1, and EV-D68. The types of CVA2, CVA10, CVA6, and CVB3 were the dominant phenotypes. In 59 sample of EV typing, the main clinical manifestation was upper respiratory tract infection (36/59, 61.01%). The dominant types detected in upper respiratory tract infections were CVA10 (10/36, 27.78%), CVA6 (9/36, 25.00%) and CVB3 (8/36, 22.22%). The dominant type detected in lower respiratory tract infections was CVA2 (7/19, 36.84%). Conclusion: In Luohe City, Henan Province from 2017 to 2021, EV infection in ARIs cases has clear seasonal and age-specific patterns, and the dominant types of upper and lower respiratory tract infections are different.


Subject(s)
Enterovirus Infections , Enterovirus , Respiratory Tract Infections , Male , Female , Humans , Enterovirus/genetics , 5' Untranslated Regions , Enterovirus Infections/epidemiology , Phenotype , Antigens, Viral/genetics , Respiratory Tract Infections/epidemiology , Phylogeny
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(7): 912-918, 2022 Jul 06.
Article in Zh | MEDLINE | ID: mdl-35899342

ABSTRACT

Objective: To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China. Methods: The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M (Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China (P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion: HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.


Subject(s)
Orthomyxoviridae , Respiratory Syncytial Virus, Human , Respiratory Tract Infections , Virus Diseases , Viruses , Child , Child, Preschool , China/epidemiology , Humans , Infant , Male , Respiratory System , Respiratory Tract Infections/epidemiology , Virus Diseases/epidemiology
6.
Zhonghua Yi Xue Za Zhi ; 101(22): 1695-1699, 2021 Jun 15.
Article in Zh | MEDLINE | ID: mdl-34126719

ABSTRACT

Objective: To study the prevalence and genetic characteristics of human respiratory syncytial virus (HRSV) in Quanzhou city, from 2018 to 2019. Methods: A total of 141 throat swabs were collected from children patients of lower respiratory tract infection in Quanzhou children Hospital, Fujian Province from November 2018 to May 2019. RT-PCR was used to amplify the 3 'end of G gene HRSV. Sequencer 5.0 and MEGA5.05 softwares were used for sequence editing, phylogenetic tree construction and genotyping analysis. Results: Twenty-five samples were positive for HRSV. Seventeen samples succeeded to obtain the target gene, including 13 of HRSVA and 4 of HRSVB. Two genotypes were identified: ON1 genotype (13 samples, HRSVA) and BA9 genotype (4 samples, HRSVB). Five strains of ON1 genotype sequences were clustered with the ON1 sequences prevalent in Beijing, Changchun and Zhejiang from 2012 to 2015 (cluster1); one strain (FJ19-02) was clustered with the sequences of ON1 genotype circulating in many regions of China from 2012 to 2015 (cluster2); Seven strains were clustered independently (cluster FJ). FJ18-02, FJ19-14 and FJ19-15 of HRSVB were clustered with the BA9 genotype sequences prevalent in Changchun, Jilin Province in 2015, while FJ19-13 was closely related to the BA9 genotype sequences prevalent in Guangzhou and Zhejiang Province in 2013. Both the ON1 and BA9 genotypes showed variations of nucleotide and amino acid in 72 and 60 insertion segments. Amino acid mutation (H266L) only occurred among the sequence of cluster-FJ, and the mutations of H261Q and Q265L only appeared in strain FJ19-13. Conclusion: BA9 and ON1 genotypes were prevalent in Quanzhou city, from 2018 to 2019. Cluster-FJ was a newly discovered independent transmission chain, which may continue to circulate in local Quanzhou area.


Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Beijing , Child , China/epidemiology , Genetic Variation , Genotype , Humans , Infant , Phylogeny , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus, Human/genetics , Sequence Analysis, DNA
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(8): 931-937, 2021 Aug 06.
Article in Zh | MEDLINE | ID: mdl-34445830

ABSTRACT

Objective: The purpose of this study was to investigate the characteristics of viral pathogen spectrum and the epidemiological characteristics of each viral pathogen in hospitalized cases associated with severe acute respiratory infection (SARI) in Luohe City, Henan Province from 2017 to 2019. Methods: Based the SARI Case Surveillance Platform, SARI cases were collected in Central Hospital of Luohe City, Henan Province from November 2017 to February 2019. In the end, 783 SARI cases were included, whose throat swabs were taken within 24 h of admission, as well as their demographic characteristics, onset time, clinical characteristics and other information recorded. At the same time, viral identification was performed, and the age and time distribution of each virus were analyzed. Results: The age of 783 SARI cases shown as M (P25, P75) was 3 (1, 5) years old, ranging from 1 month to 95 years old. Children under 5 years old were the majority (71.01%). The males (61.81%) were more than females (38.18%). Among the 783 SARI cases, a total of 9 kind of viruses were identified with 64.88% (508/783) of the throat swabs tested positive for at least one virus. The positive rate of influenza virus and human respiratory syncytial virus were both 20.18% (158 cases), which was the highest among all the detected respiratory virus. The co-infection rate was 15.84% (124/783), among which double infection was the most common, accounting for 85.48% (106/124) of the co-infected cases. And human respiratory syncytial virus, human rhinovirus and influenza virus were the most common pathogen in co-infection cases. Moreover, the viral positive rate was 68.71% in children aged 5 years and 63.27% in people aged 60-95 years. Influenza and human respiratory syncytial virus dominated in winter and spring, while human parainfluenza virus was the main infection in summer. Conclusion: Influenza virus and human respiratory syncytial virus were the main viruses in throat swabs of SARI cases from 2017 to 2019 in Luohe City, Henan Province. There were differences in the age and seasonal epidemiological characteristics of each virus.


Subject(s)
Influenza, Human , Orthomyxoviridae , Respiratory Tract Infections , Viruses , Child , Child, Preschool , Female , Humans , Infant , Influenza, Human/epidemiology , Male , Respiratory Tract Infections/epidemiology , Spectrum Analysis
8.
Zhonghua Gan Zang Bing Za Zhi ; 24(4): 285-90, 2016 Apr.
Article in Zh | MEDLINE | ID: mdl-27470628

ABSTRACT

OBJECTIVE: To investigate the influence of the PI3K/AKT signaling pathway on the proportion and characteristics of the stem-like CD90(+) subpopulation of the human hepatocellular carcinoma (HCC) cell line MHCC-97. METHODS: MHCC-97H cultures were treated with the PI3K/AKT pathway inhibitor LY294002. The proportion of the CD90(+) subpopulation was determined by flow cytometry, and the expression of related proteins was measured by Western blot. The clonogenicity of CD90(+) and CD90(-) cells was measured by plate colony formation assay. The tumorigenicity was compared between CD90(+) and CD90(-) subpopulations (with different concentrations) in xenograft experiments in nude mice, and the changes in tumorigenicity after the addition of LY294002 were evaluated. The changes in the expression of CD90, SHP2, P-AKT, and AKT in CD90(+) and CD90(-) cell xenografts after the addition of LY294002 were examined. Data were analyzed using t test. RESULTS: LY294002 was capable of reducing the proportion of CD90(+) HCC stem cells from 2.98%±0.08% to 0.78%±0.08% (t = 32.400, P < 0.01) and reducing the clonogenicity of CD90(+) subpopulation from 95.13%±3.78% to 61.82%±7.23% (t = 7.617, P < 0.01). However, it showed no significant effect on the clonogenicity of CD90(-) subpopulation. LY294002 also reduced the tumorigenicity of CD90(+) subpopulation and the expression of CD90, SHP2, and P-AKT in related HCC stem cells, but it did not significantly affect the expression of AKT. LY294002 had no significant inhibitory effect on the tumorigenicity of CD90(-) cells. CONCLUSION: The CD90(+) subpopulation of MHCC-97H cells has the characteristics of stem cells and is dependent on the PI3K/AKT signaling pathway.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Neoplastic Stem Cells/cytology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Thy-1 Antigens/metabolism , Animals , Cell Line, Tumor , Chromones , Humans , Liver Neoplasms/metabolism , Mice , Mice, Nude , Morpholines , Neoplasm Transplantation
9.
Genet Mol Res ; 14(2): 6289-96, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26125831

ABSTRACT

Single-nucleotide polymorphisms in microRNAs (miRNAs) may dramatically affect gene expression and subsequently alter individual susceptibility to cancer, and thus has become a research hotspot for many cancer types, including breast cancer. We recruited 321 breast cancer patients and 290 controls in our study. Four established miRNA single-nucleotide polymorphisms (mir-499 rs3746444 A>G; miR-27a rs895819 A>G; miR-196a2 rs11614913 T>C; miR-146a rs2910164 G/C) were detected using Taqman assays. Mature miRNA expression, allele distribution, and the association with clinical features were further analyzed. Our results showed that the miR146a rs2910164 G/C polymorphism was associated with an elevated risk of breast cancer (odds ratio = 1.85, 95% confidence interval = 1.03-3.32; P < 0.05). Compared with the ancestral T allele in miR-196a2 rs11614913, the variant C allele was consistently associated with an increased risk of breast cancer (odds ratio = 2.20, 95% confidence interval = 1.19-4.09, P < 0.01) and clinical pathological type (P < 0.01). miR-27a rs895819 A>G and miR-499 rs3746444 A>G were not associated with breast cancer risk. Analysis of mature miRNA expression confirmed that the variant C allele in miR146a rs2910164 and miR-196a2 rs11614913 dramatically inhibited production of their mature products. Our results suggested that miR-146a rs2910164 G>C and miR-196a2 rs11614913 T>C may be biomarkers for predicting breast cancer risk in the Chinese population.


Subject(s)
Breast Neoplasms/genetics , MicroRNAs/genetics , Adult , Aged , Asian People , Breast Neoplasms/pathology , Female , Gene Expression Regulation, Neoplastic , Genetic Association Studies , Genetic Predisposition to Disease , Humans , MicroRNAs/biosynthesis , Middle Aged , Polymorphism, Single Nucleotide/genetics
10.
Nanotechnology ; 20(50): 505602, 2009 Dec 16.
Article in English | MEDLINE | ID: mdl-19907065

ABSTRACT

Thick titania films of highly ordered orthorhombic pore organization and sufficient thickness up to a few micrometers have been synthesized via a supramolecular templated route and layer-by-layer deposition. An appropriate pre-heat treatment was applied to improve the mesopore accessibility. The mesoporous films were highly crystallized with the crystallite size of approximately 12 nm regardless of the film thickness, due to the spatial confinement of mesopores. A high optical transparency was demonstrated for the mesoporous films, which is ascribed to the high mesoporosity and uniformity of the ordered film structure. Both the mesopore accessibility and optical transparency have contributed to the high performance of these films as photoanodes in the dye-sensitized solar cells, showing a maximum solar energy conversion efficiency of 6.02% for a film of 5.08 microm in thickness.

11.
Eur Rev Med Pharmacol Sci ; 20(7): 1283-7, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27097947

ABSTRACT

OBJECTIVE: To study miroRNA-195 (miR-195) expression in the serum and cancer tissue of patients with gastric cancer and to investigate the relationship between its expression and clinicopathological features of gastric cancer. PATIENTS AND METHODS: Sixty-two patients with gastric cancer admitted to our institution were included in the study group, and 36 healthy persons undergoing health check-up at our institution served as control group. miR-195 expressions in the serum, gastric cancer tissue and corresponding paracancerous tissue in subjects of two groups were measured by using quantitative fluorescent real-time PCR (QF-RT-PCR), and the relationship between miR-195 and the clinicopathological features of the cancer was investigated. RESULTS: miR-195 expression level in the serum of gastric cancer patients was significantly lower than that in the control group (p <0.05). miR-195 expression in gastric cancer tissue was also significantly lower than that in corresponding paracancerous tissue (p <0.05). The results of correlation analysis showed that low expression of miR-195 was negatively correlated with the infiltration depth, the extent of differentiation, the clinical staging and lymph node metastasis, all with statistical significance (p <0.05), but not significantly correlated with tumor locations (p >0.05). CONCLUSIONS: Low expression of miR-195 in patients with gastric cancer may play a certain role in promoting the genesis and development of gastric cancer and it can function as a potential novel tumor marker for the early diagnosis and prognosis evaluation of gastric cancer.


Subject(s)
Biomarkers, Tumor/genetics , Blood Cells/metabolism , MicroRNAs/genetics , Stomach Neoplasms/genetics , Aged , Blood Cells/pathology , Case-Control Studies , Cell Differentiation/genetics , Female , Humans , Lymphatic Metastasis , Male , MicroRNAs/blood , Middle Aged , Neoplasm Staging , Prognosis , Real-Time Polymerase Chain Reaction , Stomach Neoplasms/blood , Stomach Neoplasms/diagnosis , Stomach Neoplasms/pathology
13.
Nanotechnology ; 19(40): 405701, 2008 Oct 08.
Article in English | MEDLINE | ID: mdl-21832630

ABSTRACT

Ordered, closely packed, and vertically oriented titania nanotube arrays with lengths exceeding 10 µm were fabricated by anodization of titanium foils. The effects of anodization voltage and time on the microstructural morphology and the photovoltaic performance of dye sensitized solar cells based on the titania nanotube arrays were investigated. On increasing the anodization voltage or time, the increase in active surface area leads to enhanced photovoltaic currents and thereby an overall higher performance of the dye sensitized solar cells. The efficiency enhancement with rising anodization voltage exceeds the increase in the outer surface area of the nanotubes, indicating that the active surface area is further enlarged by a more accessible inner surface of the nanotube arrays grown with a higher anodization voltage. A promising efficiency of 3.67% for dye sensitized solar cells based on anodized titania nanotube arrays was achieved under AM1.5, 100 mW cm(-2) illumination.

14.
Ecotoxicol Environ Saf ; 64(2): 226-33, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16406581

ABSTRACT

Growth and physiological responses of rice to lanthanum were studied to elucidate the function of lanthanum in plants and its critical concentration relative to environmental safety. Shoot La content increased with the increasing added La concentrations. When shoot La content exceeded a toxic value, plant growth and chlorophyll a/b decreased and peroxidase (POD) activity, cell membrane permeability, and content of proline in the leaf increased. Leaf chlorophyll a/b and POD activity might provide useful criteria for early diagnoses of phytotoxicity of soil contaminated by La. In the present study, the critical concentration of La for rice relative to environmental safety was suggested to be 42.03 mg kg(-1) in red soil and 83.33 mg kg(-1) in paddy soil.


Subject(s)
Lanthanum/toxicity , Oryza , Seeds , Soil Pollutants/toxicity , Cell Membrane Permeability/drug effects , Chlorophyll/metabolism , Chlorophyll A , Dose-Response Relationship, Drug , Lanthanum/analysis , Oryza/drug effects , Oryza/growth & development , Oryza/physiology , Peroxidase/metabolism , Plant Leaves/metabolism , Seeds/drug effects , Seeds/growth & development , Seeds/physiology , Soil/analysis , Soil Pollutants/analysis
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