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1.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(11): 837-841, 2022 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-36510718

RESUMO

Objective: To investigate the sleep quality of video operators in Shenzhen, and explore the relationship between sleep quality and occupational stress and different work and life habits. Methods: In December 2020, a cluster sampling method was used to investigate 791 video operators in Shenzhen from June to December 2020 who were engaged in printing, design, IT and other industries. The Pittsburgh Sleep Quality Index Scale was used to investigate the sleep quality of video operators, and the Job Content Questionnaire was used to investigate the occupational stress of video operators, The Pay Return Imbalance Questionnaire was used to investigate the pay return imbalance of video operators. The measurement data conforming to the normal distribution shall be expressed by mean±standard deviation, and t-test, analysis of variance and linear correlation analysis shall be adopted according to the type of independent variable. Those that do not conform to the normal distribution are described by the median M (Q(1), Q(3)), and two sample Wilcoxon test is used according to the binary data of independent variable type. Kruskal Wallis test was used for multi classification data, and Spearman rank correlation was used for single factor analysis for ordinal classification data. The counting data were analyzed by chi square test or Fisher exact probability method. Logistic regression was used for multivariate analysis. Results: the pittsburgh sleep quality index was 4.76±2.86. 499 of them had high sleep quality. 292 people had low sleep quality, accounting for 36.91% (292/791). Compared with the low sleep quality group, the high sleep quality group had lower work requirement scores (13.48±1.77), higher autonomy scores (24.08±3.33), higher social support scores (23.95±3.08), lower pay scores (16.11±2.63), higher return scores (31.11±3.65), and lower internal input scores (14.98±2.55). There were statistically significant differences between the two scales in each dimension index group (P<0.05). Multi factor unconditional logistic regression analysis showed that high education level (OR=1.57, 95%CI=1.26~1.98, P<0.05), occupational stress (OR=1.69, 95%CI=1.21~2.36, P<0.05), and high pay and low return (OR=1.41, 95%CI=1.01~1.96, P<0.05) were the main influencing factors of sleep quality. Conclusion: The occurrence of occupational stress in video operators is a risk factor for low sleep quality, which should be paid enough attention.


Assuntos
Estresse Ocupacional , Estresse Psicológico , Humanos , Estresse Psicológico/epidemiologia , Terminais de Computador , Qualidade do Sono , Estudos Transversais , Estresse Ocupacional/epidemiologia , Inquéritos e Questionários
2.
Artigo em Chinês | MEDLINE | ID: mdl-35915939

RESUMO

Objective: To understand the occurrence of occupational injuries among sanitation workers in Shenzhen, and provide a scientific basis for the prevention of occupational injuries among sanitation workers. Methods: From May to November 2020, a cluster sampling method was used to select some street sanitation workers in Shenzhen to conduct a questionnaire survey. A total of 2200 questionnaires were recovered, of which 2167 were valid (98.5% effective recovery rate) . The socio-demographic data, length of service, type of work and occurrence of occupational injuries of sanitation workers were collected, and the distribution characteristics of occupational injuries and their relationship with factors such as type of work were analyzed. Results: Among the 2167 sanitation workers, 240 (11.1%) had experienced occupational injuries. The most common occupational injuries among sanitation workers were sharp injury, heat stroke and motor vehicle traffic accident, with the incidence rates of 6.1% (133/2167) , 2.4% (53/2167) and 1.7% (36/2167) respectively. There were statistically significant differences in the distribution of occupational injuries among sanitation workers with different lengths of work and types of work (P<0.05) . The incidence of occupational injury among sanitation workers with more than 5 years of service was significantly higher than that of workers with less than 5 years of service (P<0.05) . The incidence of sharp injury among garbage sorting and transportation personnel was higher (7.9%, 21/265) , the incidence of heat stroke among manual cleaners was higher (3.1%, 42/1366) , and the incidence of motor vehicle traffic accident among mechanized cleaners was higher (5.4%, 10/184) . Conclusion: There are many cases of occupational injuries among sanitation workers in Shenzhen. Targeted measures should be taken to prevent the occurrence of different types of work and different types of occupational injuries, and to improve the occupational health level of sanitation workers.


Assuntos
Golpe de Calor , Saúde Ocupacional , Traumatismos Ocupacionais , Acidentes de Trabalho , Cidades , Golpe de Calor/epidemiologia , Humanos , Traumatismos Ocupacionais/epidemiologia , Saneamento
3.
Artigo em Chinês | MEDLINE | ID: mdl-35785894

RESUMO

Objective: To compare the ophthalmic examination indices of different occupational groups in Shenzhen and analyze the possible health problems, so as to provide research basis for further health intervention. Methods: In March 2021, 5426 professionals with ophthalmic examination index data were selected from the basic health database of "Shenzhen occupational population protection action". Among them, radiation workers (694), port operators (1756), sanitation workers (946), teachers (224), video workers (154), police (927) and firefighters (100) were selected as the investigated occupational population. They were exposed to noise 625 workers with traditional occupational hazards such as noise, chemical poisons and dust were used as the control population.Ophthalmic examination indices included right eye vision, left eye vision, outer eye, conjunctiva, cornea, lens, and fundus oculi. The differences of each index in different occupational groups were compared. Results: Compared with the control group, the port operator group showed lower abnormal rates of binocular vision and fundus oculi (P<0.05), but higher abnormal rates of conjunctiva (P=0.029), the environmental sanitation worker group showed higher abnormal rates of binocular vision and conjunctiva (all P<0.01), the teacher group had higher abnormal rates of binocular vision, but only the difference of left eye vision was statistically significant (P=0.021), and the video worker group had higher abnormal rates of right and left eyes vision (P=0.029、0.006) . Conclusion: There were some degrees of ophthalmic problems in different occupational population, therefore targeted intervention measures should be taken according to the characteristics of each group.


Assuntos
Cristalino , Doenças Profissionais , Poeira , Humanos , Ruído , Doenças Profissionais/epidemiologia , Ocupações
4.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 38(10): 731-735, 2020 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-33142373

RESUMO

Objective: To investigate the changes in liver function and peripheral regulatory lymphocytes before and after treatment in patients with occupational medicamentosa-like dermatitis due to trichloroethylene (OMDT) . Methods: In December 2019, 16 patients with OMDT (8 patients with erythema multiforme and 8 with erythema multiforme major) who were admitted from February 2017 to February 2019 were enrolled as subjects. Liver function parameters and percentages of peripheral regulatory lymphocytes were measured before and after treatment, and the changes in liver function and peripheral regulatory T and B lymphocytes and their correlation were analyzed. Results: Before treatment, compared with the healthy control group, the experimental group had significantly higher levels of alanine aminotransferase (ALT) , aspartate aminotransferase (AST) , total bilirubin (TBIL) , direct bilirubin (DBIL) and gamma-glutamyl transpeptidase (GGT) and significantly lower levels of total protein (TP) , albumin (ALB) and cholinesterase (CHE) (P<0.05) . Compared with the healthy control group, the experimental group had significantly lower percentages of lymphocytes, CD4(+) T cells, CD4(+)CD25(+) Tregs, CD19(+)CD24(+)CD27(+) Bregs and CD4(+)/CD8(+) ratio, as well as a significantly higher percentage of CD8(+) T cells (P<0.05) . Before treatment, the levels of ALT, AST, GGT and DBIL were negatively correlated with the percentages of CD4(+)CD25(+) Tregs, CD19(+)CD24(+)CD27(+) Bregs, CD4(+) T cells and CD4(+)/CD8(+) ratio (r=-0.386 to -0.809, P<0.05) and was positively correlated with the percentage of CD8(+) T cells (except DBIL) (r=0.503-0.568, P<0.05) . The levels of TP and ALB were positively correlated with the percentages of CD4(+)CD25(+) Tregs, CD19(+)CD24(+)CD27(+)Bregs and CD4(+) T cells (r= 0.351-0.784, P<0.05) , ALB was negatively correlated with the percentage of CD8(+) T cells (r=-0.315, P<0.05) . CHE was positively correlated with the percentages of CD4(+)CD25(+) Tregs, CD19(+)CD24(+)CD27(+)Bregs and CD4(+)/CD8(+) ratio (r=0.390-0.527, P<0.05) . Conclusion: Immune dysfunction is observed in patients with OMDT, which may be caused by the imbalance of regulatory lymphocytes. And liver injury may be associated with the increase of CD8(+) T cells and the reductions of percentages of CD4(+) T cells, CD4(+)CD25(+) Tregs, CD19(+)CD24(+)CD27(+)Bregs and CD4(+)/CD8(+) ratio.


Assuntos
Linfócitos B Reguladores , Dermatite Ocupacional , Tricloroetileno , Linfócitos T CD8-Positivos , Humanos , Linfócitos T Reguladores , Tricloroetileno/toxicidade
5.
Artigo em Chinês | MEDLINE | ID: mdl-33036528

RESUMO

Objective: To research the mitochondrial cytochrome c oxidase subunit I (MT-COI) gene methylation levels in patients with occupational chronic benzene poisoning, and to explore effective molec µlar biomarkers in patients with occupational chronic benzene poisoning. Methods: 38 confirmed cases of occupational chronic benzene poisoning were selected in the case group. 46 healthy people who underwent physical in our hospital were selected in the control group. Pyrosequencing was used to detect the methylation sites of methylation sites, flow cytometry was used to detect peripheral blood cell count levels, and non-parametric statistical methods were used to analyze the differences in detection results between the two groups. Results: The methylation level of mitochondrial MT-COI site 1 (2.21±0.81) % in the case group was less than that in the control group, and the difference was statistically significant (P<0.05) . The methylation level of mitochondrial MT-COI site 2 (2.31±0.96%) in the case group was less than that in the control group, and the difference was statistically significant (P<0.05) . The methylation average level of mitochondrial MT-COI (2.26±0.75) % in the case group was less than that in the control group, and the difference was statistically significant (P<0.05) . Analysis of the average level of methylation found that the methylation level of mitochondrial MT-COI was correlated with WBC (P<0.05) . Analysis of the average level of methylation found that the methylation level of mitochondrial MT-COI was correlated with platelets (r=0.254、0.280, P<0.05) . Conclusion: The level of mitochondrial MT-COI gene methylation in patients with occupational chronic benzene poisoning may be related to the sensitivity to benzene exposure. Mitochondrial MT-COI gene methylation may serve as a potential predictive biomarker for benzene poisoning.


Assuntos
Benzeno , Exposição Ocupacional , Metilação de DNA , Humanos
6.
Artigo em Chinês | MEDLINE | ID: mdl-32629578

RESUMO

Objective: To explor staging of the general course of occupational medicamentosa-like dermatitis due to trichloroethylene (OMDT) to better understand the characteristics of OMDT course, and to provide reference for clinical diagnosis and treatment and related studies. Methods: We collected main clinical manifestation and auxiliary examination data during hospitalization to May 2019 from 35 OMDT patients with complete course record who were hospitalized from January 2014 to December 2018. Continuous monitoring indicators with changing trends including main clinical manifestation indicators, peripheral white blood cell counts, liver function indicators such as serum alanine aminotransferase activity, myocardial enzyme indicators such as serum lactate dehydrogenase activity were selected and used with their standardized values to do cluster analysis on time point (week as unit) of the course of each patient. The clustering results combined with changing trends of the indicators were used to determine the stages of course of each patient, and therefore the staging of general course of OMDT was calculated. Positive rates or average levels of the indicators were compared between different stages, and the correlation of duration of each stage was analyzed with physical characteristics, disease characteristics and treatment measures of the patients. Results: General course of OMDT could be divided into acute phase (3.0±1.5) weeks and chronic phase (11.0±4.4) weeks, while chronic phase could be further divided into early period (5.0±3.0) weeks and later period (6.5±3.7) weeks. Compared with chronic phase, clinical manifestation indicators, white blood cell counts (except eosinophil count) , liver function indicators (except total protein and albumin concentration) , and myocardial enzyme indicators were all increased (all P<0.01) , while total protein and albumin concentration decreased (P<0.05 and P<0.01, respectively) in acute phase. Compared with later period of the chronic phase, clinical manifestation indicators (except fever) , white blood cell counts (except lymphocyte count) , liver function indicators (except total protein and albumin concentration) , and creatine kinase isoenzyme activity were all increased (all P<0.01) , while total protein, albumin concentration and creatine kinase activity decreased (all P<0.01) . Duration of acute phase were positively correlated with the time before glucocorticoid treatment (r(spearman)=0.62, P(adjust)<0.01) , and early and later periods of chronic phase were both positively correlated with corresponding duration of glucocorticoid treatment (r(spearman)=0.96, P(adjust)<0.01, r(spearman)=0.91, P(adjust)<0.01, respectively) . Conclusion: For the first time, the study objectively determined stages of general course of OMDT based on combination of multiple indicators, and analyzed characteristics of main indicators in each phase and potential factors related to the duration of each phase.


Assuntos
Dermatite Ocupacional , Tricloroetileno , Humanos , Contagem de Leucócitos , Contagem de Linfócitos , Soro
7.
Artigo em Chinês | MEDLINE | ID: mdl-29081127

RESUMO

Objective: To investigate the detection of a human leukocyte antigen-B (HLA-B) allele HLA-B*13:01 by dual allele-specific real-time polymerase chain reaction (PCR) in patients with trichlorethylene-induced dermatitis. Methods: A total of 20 patients with trichlorethylene-induced dermatitis who were admitted and treated from January 2014 to October 2016 were enrolled as case group, and 20 persons who underwent physical examination from January to October, 2016 were enrolled as control group. Peripheral cubital venous blood samples were collected from all subjects, and dual allele-specific real-time PCR was used to detect the HLA-B*13:01 gene. The two groups were compared in terms of the proportion of subjects carrying HLA-B*13:01 gene. Results: There were no significant differences between the case group and the control group in median age (25.0 years vs 27.0 years, Z=0.30, P>0.05) and the proportion of male subjects (60.0% vs 70.0%, χ(2)=0.44, P>0.05) . The mean time of exposure to trichloroethylene was 30.8 days in the case group, while the subjects in the control group were not exposed to trichloroethylene. The case group had a significantly higher frequency of HLA-B*13:01 gene than the control group (80.0% vs 20.0%, χ(2)=14.40, P<0.01) with an odds ratio of 16.00. Conclusion: Dual allele-specific real-time PCR can be used for detection of the HLA-B*13:01 gene in patients with trichlorethylene-induced dermatitis.


Assuntos
Dermatite Ocupacional/genética , Predisposição Genética para Doença , Antígenos HLA-B/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Tricloroetileno/efeitos adversos , Adulto , Alelos , Dermatite Ocupacional/etiologia , Frequência do Gene , Genótipo , Humanos , Masculino , Polimorfismo Genético
8.
Eur J Clin Microbiol Infect Dis ; 33(8): 1339-44, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24550039

RESUMO

Treatment guidelines recommend combination antifungal therapy with amphotericin B (AmB) as an induction therapy for cryptococcal meningitis. The objective of this study was to compare the survival benefit between 5-FC (flucytosine) and fluconazole as second-line drugs given in combination with AmB. We carried out a systematic review and meta-analysis of prospective controlled studies reporting early combination treatment for human immunodeficiency virus (HIV)-associated cryptococcal meningitis. We searched MEDLINE, EMBASE and the Cochrane Library up to October 2013. Randomised trials and prospective cohort studies were selected. The primary outcome was mortality in the first 14 and 70 days. The secondary outcome was early fungicidal activity (EFA) in the first 2 weeks. Four trials were included in our study. All included studies could be considered to be of fair quality in their methodology. The meta-analysis suggested that mortality was lower in patients who were given AmB and 5-FC at the 2 weeks point (Fig. 2); the overall reduction in mortality with the 5-FC combination group was 44% [risk ratio (RR) 0.56, 95% confidence interval (CI) 0.33-0.95, p = 0.03]. EFA was significantly shorter in patients receiving AmB plus 5-FC [mean difference (MD) -0.10 log10 colony-forming units (CFU) per day, 95 % CI -0.11-0.09, p < 0.00001]. Mortality was no different between the 5-FC and fluconazole groups at the 3 months time point (p = 0.15) (Fig. 4). Adverse events occurred with similar frequency between the two treatment groups. There was no statistically significant difference in the survival rate between AmB in combination with high-dose fluconazole and the current standard of AmB plus 5-FC therapy for HIV-associated cryptococcal meningitis.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Fluconazol/uso terapêutico , Flucitosina/uso terapêutico , Infecções por HIV/imunologia , Meningite Criptocócica/tratamento farmacológico , Coinfecção , Quimioterapia Combinada , Infecções por HIV/mortalidade , Humanos , Hospedeiro Imunocomprometido , Meningite Criptocócica/imunologia , Meningite Criptocócica/mortalidade , Resultado do Tratamento
9.
Environ Technol ; 33(22-24): 2595-601, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23437659

RESUMO

In the last ten years, as international environmental protection consciousness has increased, the study and applications of green building, green construction materials and energy savings as well as reduction of carbon dioxide have become urgent issues for governments. In Taiwan, joss papers are burned in more than 11,731 registered shrines or temples in traditional Chinese deity or ancestor worship ceremonies during special holidays or occasions. Instead of placing this large amount of burned joss paper ash (BJPA) in landfills, this study proposes recycling BJPA by replacing some cement with calcined BJPA (CBJPA) in mortar specimens. After BJPA samples were calcined at a high kiln temperature, mortar samples were created using CBJPA to replace cement at seven different levels: 0%, 5%, 10%, 15%, 20%, 25% and 30%. Tests like setting time and compressive strength were performed for macro-analyses; scanning electron microscopy-energy dispersive spectroscopy, X-ray diffraction and thermal gravimetric analysis/differential thermal analysis were carried out for the microstructure and chemical composition analyses. The test results showed that the compressive strengths of specimens with different levels of CBJPA replacement were apparently less than those of the control group (0% CBJPA) at all curing times. The compressive strength and setting time both decreased as the fraction of CBJPA in the mortar increased. Furthermore, because the hydration product did not cement and the mortar specimen structure was loose, the expected strength improvement from the pozzolanic reaction provided by the CBJPA was not clearly observed.


Assuntos
Materiais de Construção , Papel , Microscopia Eletrônica de Varredura , Taiwan , Termogravimetria
10.
J Hazard Mater ; 168(2-3): 1105-10, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19339111

RESUMO

This study investigated the effects of phosphate on the hydration characteristics of three eco-cement clinkers made utilizing water purification sludge ash, sewage sludge ash and industry sludge ash. Analytical results demonstrate that the eco-cement A (ECO-A) pastes had a similar setting times, final setting times, compressive strengths and degree of hydration as ordinary Portland cement (OPC) pastes. Analytical results also show no damage to the hydration existed during the clinkerization process when adding up to 20% sludge. Increasing the P(2)O(5) content in the investigated clinker resulted in the formation of alpha-C(2)S. Compressive strength, degree of hydration and delay in setting time observed in the ECO-B and ECO-C pastes may be attributed to large amounts of alpha-C(2)S. When the amount of phosphate in ECO-C exceeded 0.46%, the amount of C(3)S in the clinker decreased, setting time increased and the strength of the eco-cement decreased.


Assuntos
Materiais de Construção , Ecologia , Fosfatos/química , Esgotos , Água/química , Espectroscopia de Ressonância Magnética , Taiwan
11.
Water Sci Technol ; 57(2): 243-50, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18235178

RESUMO

In order to extend the recycling of waterworks sludge to engineering applications, this paper addresses the influence of nano-SiO2 on incinerated waterworks sludge ash (IWSA) cement paste attacked by sulfate. Tests were performed such as length measurement for volume change, compressive strength, weight loss, and micro-structural testing using scanning electron microscopy (SEM). The results indicate that when a portion of the cement in the paste was replaced by IWSA, the IWSA diluted the cementitious material C3A, and filled the capillary pores in the hardened paste. Moreover, since IWSA has potential pozzolanic activity, it can chemically react with Ca(OH)2 crystals in the paste and can consequently improve the resistance of the paste to sulfate attack. Test results also show that due to the fully developed pozzolanic effect of IWSA, the major reaction products of sulfate attack, gypsum and ettringite, were clearly reduced. Hence, the expansion rate in length decreased with the increase of IWSA replacement. Furthermore, the addition of nano-SiO2 to IWSA cement paste can also reduce the length expansion rate.


Assuntos
Materiais de Construção , Excipientes/química , Temperatura Alta , Esgotos/química , Dióxido de Silício/química , Eliminação de Resíduos Líquidos , Água/química , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Sulfatos/química
12.
Waste Manag ; 28(3): 502-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17433656

RESUMO

In this article, glaze with different colorants was applied to tile specimens manufactured by incinerated sewage sludge ash (ISSA) and clay. Improvements using different amounts of colorants, and glaze components and concentrations on tile bodies were investigated. Four different proportions of clay (by weight ratio) were replaced by ISSA. Tiles of size 12 cm x 6 cm x 1 cm were made and left in an electric furnace to make biscuit tiles at 800 degrees C. Afterwards, four colorants, Fe2O3 (red), V2O5 (yellow), CoCO3 (blue), and MnO2 (purple), and four different glaze concentrations were applied on biscuit tile specimens. These specimens were later sintered into glazed tiles at 1050 degrees C. The study shows that replacement of clay by sludge ash had adverse effects on properties of tiles. Water absorption increased and bending strength reduced with increased amounts of ash. However, both water absorption and bending strength improved for glazed ash tiles. Abrasion of grazed tiles reduced noticeably from 0.001 to 0.002 g. This implies glaze can enhance abrasion resistance of tiles. Effects like lightfastness and acid-alkali resistance improved as different glazes were applied on tiles. In general, red glazed tiles showed the most stable performance, followed by blue, yellow, and purple.


Assuntos
Materiais de Construção/análise , Incineração , Esgotos/química , Silicatos de Alumínio , Argila , Conservação dos Recursos Naturais/métodos , Indústrias , Tecnologia
13.
J Environ Manage ; 88(4): 708-14, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17498863

RESUMO

The effects of nano-SiO(2) on three ash particle sizes in mortar were studied by replacing a portion of the cement with incinerated sewage sludge ash. Results indicate that the amount of water needed at standard consistency increased as more nano-SiO(2) was added. Moreover, a reduction in setting time became noticeable for smaller ash particle sizes. The compressive strength of the ash-cement mortar increased as more nano-SiO(2) was added. Additionally, with 2% nano-SiO(2) added and a cure length of 7 days, the compressive strength of the ash-cement mortar with 1 microm ash particle size was about 1.5 times better that of 75microm particle size. Further, nano-SiO(2) functioned to fill pores for ash-cement mortar with different ash particle sizes. However, the effects of this pore-filling varied with ash particle size. Higher amounts of nano-SiO(2) better influenced the ash-cement mortar with larger ash particle sizes.


Assuntos
Materiais de Construção , Nanotecnologia , Tamanho da Partícula , Esgotos , Dióxido de Silício/química , Microscopia Eletrônica de Varredura , Difração de Raios X
14.
Waste Manag ; 28(6): 1081-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17512717

RESUMO

Sewage sludge ash has been widely applied to cementitious materials. In this study, in order to determine effects of nano-SiO(2) additives on properties of sludge/fly ash mortar, different amounts of nano-SiO(2) were added to sludge/fly ash mortar specimens to investigate their physical properties and micro-structures. A water-binding ratio of 0.7 was assigned to the mix. Substitution amounts of 0%, 10%, 20%, and 30% of sludge/fly ash (1:1 ratio) were proposed. Moreover, 0%, 1%, 2%, and 3% of nano-SiO(2) was added to the mix. Tests, including SEM and compressive strength, were carried out on mortar specimens cured at 3, 7, and 28 days. Results showed that sludge/fly ash can make the crystals of cement hydration product finer. Moreover, crystals increased after nano-SiO(2) was added. Hence, nano-SiO(2) can improve the effects of sludge/fly ash on the hydration of mortar. Further, due to the low pozzolanic reaction active index of sludge ash, early compressive strengths of sludge/fly ash mortar were decreased. Yet, nano-SiO(2) could help produce hydration crystals, which implies that the addition of nano-SiO(2) to mortar can improve the influence of sludge/fly ash on the development of the early strength of the mortar.


Assuntos
Carbono/química , Materiais de Construção , Incineração , Material Particulado/química , Esgotos/química , Dióxido de Silício/química , Cinza de Carvão , Conservação dos Recursos Naturais , Microscopia Eletrônica , Nanopartículas
15.
Water Sci Technol ; 50(9): 57-65, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15580995

RESUMO

In this research, nano-composites are added to sewage sludge ash to create a mixture, which then replaces part of cement. Nano-composites are manufactured from pure quartzose sand. The influences of different amounts of nano-composites and sludge ash on mortar are evaluated. Cement, sludge ash (0%, 10%, and 20%), and nano-composites (0%, 0.5%, 1%, 2%, and 3%), which defined as the percent weight of cement and sludge ash, are mixed together in batches to make mortar specimens. Results show that the flowability of sludge ash mortar reduces with increasing amount of cement replaced and of nano-composites added. The compressive strength of mortar lowers when more amounts of cement are replaced by sludge ash, but increases with more quantity of nano-composites added. Moreover, the study shows that nano-composites can fortify the compressive strength of mortar. With the help of efficiency of compressive strength, nano-composites benefit most to the mortar with replacement of 10% sludge ash, followed by the substitution of 20% and 0%.


Assuntos
Materiais de Construção , Incineração , Nanoestruturas/química , Esgotos , Força Compressiva , Nanoestruturas/ultraestrutura , Reologia , Dióxido de Silício , Taiwan
16.
J Arthroplasty ; 12(7): 777-84, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9355007

RESUMO

The posterior cruciate ligament (PCL)-retaining, meniscal bearing and the PCL-sacrificing rotating platform designs of the LCS prosthesis (DePuy, Warsaw, IN) were designed to minimally constrain knee kinematics while minimizing bone-cement-prosthesis interface stresses and polyethylene wear. The kinematics and stability of the knee following arthroplasty with these devices rely on adequate tensioning of the remaining soft tissues by management of the flexion/extension gaps at the time of surgery. In this in vitro study, the knee kinematics of the function of the quadriceps mechanism for 8 cadaveric knees were measured quantitatively before and after implantation of these 2 prosthesis designs. Following implantation of the PCL-retaining, meniscal bearing prosthesis, anterior translations during anterior drawer testing were significantly greater (P < .05) than those seen in the intact knee. Implantation of the PCL-retaining, meniscal bearing prosthesis resulted in an increase in the extension gap of 2 mm. Quadriceps force needed to achieve full extension was increased by 30% over that needed in the intact knee. The PCL-sacrificing, rotating platform prosthesis constrained anterior translation such that nearly normal anterior knee stability was reestablished; however, the extension gap was increased by 4 mm and the quadriceps force needed to achieve full extension was 50% greater than that needed in the intact knee. Attempts to achieve joint stability by increases in the thickness of the tibial component to widen the flexion/extension gaps results in compromises of quadriceps efficiency, particularly in the absence of a functioning PCL, as demonstrated in this in vitro model. Patients receiving the PCL-sacrificing prosthesis may experience difficulty in those activities requiring quadriceps power near full extension, such as rising from a chair or ascending or descending stairs.


Assuntos
Prótese do Joelho , Artroplastia do Joelho , Cadáver , Humanos , Músculo Esquelético/fisiologia , Ligamento Cruzado Posterior , Desenho de Prótese , Rotação , Coxa da Perna
17.
Avian Pathol ; 23(1): 169-74, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18671082

RESUMO

Outbreaks of swollen head syndrome (SHS) were observed in two broiler and two broiler-breeder farms in Taiwan. The disease was characterized by oedematous swelling of the head, especially surrounding the eyelids, the neck and wattles. Avian pneumovirus and Escherichia coli were isolated from birds in all four farms. In addition, Staphylococcus aureus and infectious bursal disease virus were each isolated from one farm. A serological survey of 398 birds from 11 broiler breeder farms showed 86.4% (344) of them had ELISA antibodies against turkey rhinotracheitis virus.

18.
Avian Dis ; 37(2): 591-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8395811

RESUMO

In October 1989, an epizootic duckling disease with high mortality occurred in Taiwan. The disease was characterized by droopiness, inappetence, ataxia, ruffled feathers, and watery diarrhea. Affected ducklings were lame, were unable to stand, showed opisthotonos, and often died 3 or 4 days after the onset of the disease. Tolerant maturing ducklings displayed atrophic upper bills with a protruding tongue and became stunted as they reached maturity. No diagnostic histopathologic lesions were found in these ducklings. Fourteen parvovirus isolates, 33 duck viral hepatitis virus (DVHV) isolates, two adenovirus isolates, and two reovirus isolates were obtained and identified from more than 500 sick ducklings in the epizootic. The epizootic was diagnosed as a co-outbreak of duck parvovirus infections and duck viral hepatitis. The high mortality in ducklings and the bill atrophy syndrome were reproduced in ducklings by inoculating the parvovirus isolates alone. The epizootic was controlled by an emergency immunization program of ducklings with sera collected from recovered ducks or a bivalent inactivated vaccine composed of local DVHV and parvovirus isolates.


Assuntos
Surtos de Doenças/veterinária , Patos , Infecções por Enterovirus/veterinária , Vírus da Hepatite do Pato/isolamento & purificação , Infecções por Parvoviridae/veterinária , Parvoviridae/isolamento & purificação , Doenças das Aves Domésticas/microbiologia , Animais , Infecções por Enterovirus/complicações , Infecções por Enterovirus/microbiologia , Infecções por Enterovirus/mortalidade , Infecções por Enterovirus/patologia , Infecções por Parvoviridae/complicações , Infecções por Parvoviridae/microbiologia , Infecções por Parvoviridae/mortalidade , Infecções por Parvoviridae/patologia , Doenças das Aves Domésticas/mortalidade , Doenças das Aves Domésticas/patologia , Taiwan/epidemiologia
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