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1.
BMJ Open ; 14(5): e083532, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38719301

RESUMO

OBJECTIVE: To assess the correlation between the effort-reward imbalance (ERI) and sleep quality among railway locomotive stewards. DESIGN: Cross-sectional study. SETTING: Lanzhou Bureau Group, China Railway, between July and August 2022. PARTICIPANTS: Railway locomotive stewards. PRIMARY AND SECONDARY OUTCOME MEASURES: Sleep quality was assessed using the Pittsburgh Sleep Quality Index Scale (PSQI), categorising scores of >14 as poor, 8-14 as fair and <8 as good. RESULTS: A total of 5738 valid questionnaires (mean age of 30.85±6.91 years and 5730 males) were included. The response rate was 92.27%. The PSQI score was 11.52±3.95; 2304 (40.15%) respondents had good sleep quality, 1590 (27.71%) had fair sleep quality and 1844 (32.14%) had poor sleep quality. Stepwise multivariable logistic regression analysis showed that, compared with poor sleep quality, Jiayuguan Locomotive Depot workers (OR 0.775, 95% CI 0.587 to 0.971, p=0.028), electric locomotive drivers (OR 0.499, 95% CI 0.316 to 0.786, p=0.003), passenger train locomotive drivers (OR 0.209, 95% CI 1.313 to 3.337, p=0.002), working <40 hours weekly (OR 2.291, 95% CI 1.686 to 3.112, p<0.001), working 40-50 hours weekly (OR 1.602, 95% CI 1.299 to 1.977, p<0.001), senior titles (OR 0.727, 95% CI 0.570 to 0.928, p=0.010), high effort/low reward (OR 2.812, 95% CI 2.218 to 3.564, p<0.001) and low overcommitment (OR 5.848, 95% CI 4.710 to 7.261, p<0.001) were independently associated with fair sleep quality. Electric locomotive drivers (OR 0.535, 95% CI 0.364 to 0.787, p=0.001), diesel locomotive drivers (OR 0.567, 95% CI 0.348 to 0.924, p=0.023), passenger train locomotive drivers (OR 1.471, 95% CI 1.005 to 2.155, p=0.047), working <40 hours weekly (OR 1.549, 95% CI 1.196 to 2.006, p=0.001), working 40-50 hours weekly (OR 1.340, 95% CI 1.141 to 1.574, p<0.001), high school diploma or less (OR 1.448, 95% CI 1.062 to 1.975, p=0.019), high effort/low reward (OR 1.237, 95% CI 1.006 to 1.521, p=0.044), balanced effort-reward (OR 0.653, 95% CI 0.478 to 0.892, p=0.007) and low overcommitment (OR 2.553, 95% CI 2.224 to 2.931, p<0.001) were independently associated with good sleep quality. CONCLUSION: The results revealed an acceptable ERI and poor sleep quality among railway stewards. ERI was correlated with sleep quality. Health education, lifestyle changes and improved work schedules may help boost sleep quality and well-being among railway locomotive stewards.


Assuntos
Ferrovias , Recompensa , Qualidade do Sono , Humanos , Masculino , Estudos Transversais , Adulto , Feminino , China/epidemiologia , Inquéritos e Questionários , Pessoa de Meia-Idade , Adulto Jovem
2.
Sensors (Basel) ; 22(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408170

RESUMO

To solve the current problem of poor weld formation due to groove width variation in swing arc narrow gap welding, an infrared passive visual sensing detection approach was developed in this work to measure groove width under intense welding interferences. This approach, called global pattern recognition, includes self-adaptive positioning of the ROI window, equal division thresholding and in situ dynamic clustering algorithms. Accordingly, the self-adaptive positioning method filters several of the nearest values of the arc's highest point of the vertical coordinate and groove's same-side edge position to determine the origin coordinates of the ROI window; the equal division thresholding algorithm then divides and processes the ROI window image to extract the groove edge and forms a raw data distribution of groove width in the data window. The in situ dynamic clustering algorithm dynamically classifies the preprocessed data in situ and finally detects the value of the groove width from the remaining true data. Experimental results show that the equal division thresholding algorithm can effectively reduce the influences of arc light and welding fume on the extraction of the groove edge. The in situ dynamic clustering algorithm can avoid disturbances from simulated welding spatters with diameters less than 2.19 mm, thus realizing the high-precision detection of the actual groove width and demonstrating stronger environmental adaptability of the proposed global pattern recognition approach.


Assuntos
Poluentes Ocupacionais do Ar , Soldagem , Poluentes Ocupacionais do Ar/análise , Algoritmos , Gases/análise , Soldagem/métodos
3.
J Clin Lab Anal ; 36(3): e24265, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35148010

RESUMO

BACKGROUND: Mycoplasma pneumoniae (MP) is a common pathogen of community-acquired pneumonia in children. In the present study, serum amyloid A (SAA), C-reactive protein (CRP), and procalcitonin (PCT) levels in children with MP infection were analyzed and the differential diagnoses of MP evaluated. METHODS: The study included 152 children with MP infection hospitalized in Tai'an Central Hospital in Shandong Province and 50 healthy children as controls. SAA, CRP, and PCT, as well as serum immunoglobulins and T lymphocyte subsets were analyzed during the acute and convalescent phases. Among the MP-infected children, 30 cases were selected to monitor the SAA, immunoglobulins, and T lymphocyte subset levels for a week. RESULTS: The SAA, CRP, PCT, IgA, and IgM levels were significantly higher in the MP-infected group than in the control group (F(SAA) = 83.91, p < 0.05; F(CRP) = 40.79, p < 0.05; F(PCT) = 60.58, p < 0.05; F(IgA) = 43.45, p < 0.05; F(IgM) = 233.88, p < 0.05). In addition, the levels of these factors were significantly higher in the acute phase than in the convalescent phase (p < 0.05). However, significant difference was not observed in the IgG level between these two groups (p > 0.05). The CD3+ and CD4+ levels in the MP-infected group were lower than in the control group ( F(CD3+) = 60.58, P < 0.05; F(CD4+) = 89.05, p < 0.05), and the CD8+ level was higher than in the control group ( F(CD8+) = 96.96, p < 0.05). The CD3+ , CD4+ , and CD8+ levels were significantly different between the acute phase and the convalescent phase (CD3+ : acute phase vs. convalescent phase, q = 2.79, p < 0.05; CD4+ : acute phase vs. convalescent phase, q = 2.83, p < 0.05; CD8+ : acute phase vs. convalescent phase, q = 3.15, p < 0.05). The changes in serum SAA levels in the MP-infected group positively correlated with the changes in IgA, IgM, and CD8+ levels and negatively correlated with CD3+ , CD4+ , and CD4+ /CD8+ . CONCLUSION: SAA, CRP, and PCT were specific markers for diagnosing early MP infection in children. These findings are important in the differential diagnosis of MP infection and clinical guidance for MP treatment.


Assuntos
Pneumonia por Mycoplasma , Pró-Calcitonina , Proteína C-Reativa/metabolismo , Criança , Humanos , Mycoplasma pneumoniae , Pneumonia por Mycoplasma/diagnóstico , Proteína Amiloide A Sérica
4.
Environ Sci Pollut Res Int ; 29(27): 41804-41819, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35099702

RESUMO

The policy of the national smart city (NSC) pilots, a new type of urbanization for future development, has been implemented in China in batches. This paper investigates the mechanism and effects of the NSC pilots on the environment. Using the prefecture-level panel data during 2004-2018 period, our multi-period difference-in-differences (DID) estimation shows that the NSC pilots causally mitigate SO2 (wastewater) pollution by 13.76% (14.36%), which is supported by a series of robustness tests. The mediating effect model indicates that green total factor productivity (GTFP) plays a partial mediating role in mitigating both SO2 and wastewater emissions, while technological innovation plays a partial mediating role in mitigating wastewater emissions. After introducing the two mediating channels into the multi-period DID model, the reduction effect for SO2 and wastewater emissions drops to 11.04% (1-e- 0.117) and 12.1% (1-e- 0.129), respectively. Comparatively, the NSC pilots contribute to the improvement of GTFP and GTFP takes the major mediating role in reducing SO2 and wastewater pollution. The heterogeneous effects of the NSC pilots show that the mitigation effect is more pronounced in cities with strong fiscal support, cities with abundant human capital, and cities with high R&D expenditure. Based on these novel findings, this study provides some policy implications for achieving better mitigation effects.


Assuntos
Poluição do Ar , Pilotos , Poluição do Ar/análise , China , Cidades , Eficiência , Poluição Ambiental , Humanos , Urbanização , Águas Residuárias
5.
J Healthc Eng ; 2021: 9637018, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868536

RESUMO

With the continuous improvement of economic level and the continuous development of science and technology in China, information technology has begun to integrate into all walks of life. Medical units have begun to change from the traditional medical system to the intelligent system, and the processing of online case information has become an important component of medical informationization. To improve the efficiency of dealing with online case information, this study proposes to establish a fully connected neural network model to deal with online cases. Using jieba word segmentation tool and data preprocessing technology, the data of electronic medical records are sorted out, and the data are quantified using Word2Vec and other tools, and the data on electronic medical records are converted into one-hot binary variables. The quantified data are trained into a fully connected neural model, and the accuracy rate is about 88%. It is compared with naive Bayes and decision tree classification methods, and then a comparative experiment is carried out by solving e-health services in different ways. The results show that the fully connected neural network model has the best classification effect: the highest accuracy rate is about 93.7%, the highest precision rate is about 94.0%, the highest recall rate is about 95.3%, and the highest F1 score is about 94.6%. However, using artificial intelligence technology to solve electronic health services has great advantages, among which efficiency, assistance, and service satisfaction are all higher than 90%, which provides favorable technical support for electronic health services.


Assuntos
Inteligência Artificial , Tecnologia , Teorema de Bayes , Eletrônica , Serviços de Saúde , Humanos
6.
Materials (Basel) ; 13(23)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255195

RESUMO

Considering the coupling of a droplet, keyhole, and molten pool, a three-dimensional transient model for the full penetration laser + metal inert gas (MIG) hybrid welding of thin copper alloy plate was established, which is able to simulate the temperature and velocity fields, keyhole behavior, and generation of the welding defect. Based on the experimental and simulation results, the weld formation mechanism for the hybrid butt welding of a 2 mm-thick copper alloy plate was comparatively studied in terms of the fluid dynamic feature of the melt pool. For single laser welding, the dynamic behavior of liquid metal near the rear keyhole wall is complex, and the keyhole has a relatively drastic fluctuation. An obvious spattering phenomenon occurs at the workpiece backside. Meanwhile, the underfill (or undercut) defect is formed at both the top and bottom surfaces of the final weld bead, and the recoil pressure is identified as the main factor. In hybrid welding, a downward fluid flow is strengthened on the rear keyhole wall, and the stability of the keyhole root is enhanced greatly. There are large and small clockwise vortexes emerging in the upper and lower parts of the molten pool, respectively. A relatively stable metal bulge can be produced at the weld pool backside. The formation defects are suppressed effectively, increasing the reliability of full penetration butt welding of the thin copper alloy plate.

7.
Materials (Basel) ; 12(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018601

RESUMO

A three-dimensional numerical model is used to simulate heat transfer and fluid flow phenomena in fiber laser + gas metal arc welding (GMAW) hybrid welding of an aluminum alloy, which incorporates three-phase coupling and is able to depict the keyhole dynamic behavior and formation process of the keyhole-induced porosity. The temperature profiles and fluid flow fields for different arc powers are calculated and the percent porosities of weld beads were also examined under different conditions by X-ray non-destructive testing (NDT). The results showed that the computed results were in agreement with the experimental data. For hybrid welding, with raising arc power, the keyhole-induced porosity was reduced. Besides the solidification rate of the molten pool, the melt flow was also closely related to weld porosity. A relatively steady anti-clockwise vortex caused by arc forces tended to force the bubble to float upwards at the high temperature region close to the welding heat source, which benefits the escape of the gas bubble from the melt pool. When increasing the arc power, the anti-clockwise region was strengthened and the risk of the gas bubble for capture by the liquid/solid interface underneath the keyhole tip was diminished, which resulted in the lower weld percent porosity.

8.
Int J Clin Exp Pathol ; 7(9): 6219-24, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337273

RESUMO

Mesothelial/monocytic incidental cardiac excrescence (MICE) is a rare and distinctive benign lesion often found during cardiac valve replacement. To date, 43 cases have been reported in the English literature. This lesion is important because of the potential for confusion with primary or metastatic malignancy. We report a case of MICE in a 47-year-old Chinese man with rheumatic heart disease whose MICE was discovered during mitral and aortic valve replacement. Histopathological examination of the lesion combined with immunohistochemistry confirmed the diagnosis of MICE.


Assuntos
Epitélio/patologia , Achados Incidentais , Monócitos/patologia , Miocárdio/patologia , Biomarcadores/análise , Biópsia , Epitélio/química , Implante de Prótese de Valva Cardíaca , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Monócitos/química , Miocárdio/química , Valor Preditivo dos Testes , Cardiopatia Reumática/diagnóstico , Cardiopatia Reumática/cirurgia
9.
Shanghai Kou Qiang Yi Xue ; 22(3): 241-6, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23852049

RESUMO

PURPOSE: To establish the digital model about sagittal split ramus osteotomy and discuss the stress and displacement of 3 different fixation methods. METHODS: Three-dimensional reconstruction software Mimics and Geomagic were used to establish the three-dimensional entity model of mandible, and simulated sagittal split ramus osteotomy and fixation. Three-dimensional finite element model was established by mesh generation through ANSYS. After boundary constraint the occlusal load of 132N on the bilateral lower first molars was applied. RESULTS: Three-dimensional finite element models of sagittal split ramus osteotomy and 3 different fixation methods were established, and the biomechanical character of stress and displacement after occlusal load preoperatively and after splitting mandibles were found. CONCLUSIONS: As the stress distribution tends to uniformity and the displacement at split area is the least one, the fixation by bicortical screws in inverted-L position after sagittal split ramus osteotomy is the stablest of the 3 fixation methods. Supported by Natural Science Foundation of Guangdong Province (S2011010003872) and Science and Technology Projects of Guangzhou City (7421165457455).


Assuntos
Análise de Elementos Finitos , Osteotomia Sagital do Ramo Mandibular , Parafusos Ósseos , Análise do Estresse Dentário , Humanos , Mandíbula , Estresse Mecânico
10.
Artigo em Chinês | MEDLINE | ID: mdl-24616994

RESUMO

OBJECTIVE: Lymphoepithelial carcinoma (LEC) of salivary glands is a rare malignant neoplasm. The purpose of this research was to investigate the clinicalpathologic features and treatment methods of this rare disease. METHOD: The clinical data and treatment outcomes of 17 patients from 2006 to 2012 were reviewed retrospectively. RESULT: Ten males and seven females with a ratio of 1. 43:1 were involved. The II, III, IV stage cases were 7 (41.2%), 4 (23.5%), 6 (35.3%), respectively. The average follow-up duration was 2.56 years, and 12 patients had no evidence of recurrence. Five patients had local recurrence and (or) distant metastases within three years after surgery, including 4 deaths. CONCLUSION: LEC in salivary gland is a high grade malignant tumor in oral and maxillofacial region, occurring predominately in parotid gland and submandibular gland. To prevent distant metastasis, radical surgery combined with chemoradiotherapy should be adopted.


Assuntos
Recidiva Local de Neoplasia , Neoplasias de Células Escamosas/patologia , Doenças Raras/patologia , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Células Escamosas/secundário , Neoplasias Parotídeas/patologia , Estudos Retrospectivos , Glândulas Salivares/patologia , Neoplasias da Glândula Submandibular/patologia , Resultado do Tratamento
12.
Artigo em Inglês | MEDLINE | ID: mdl-17889595

RESUMO

A new substrate of "gold nano-particle/silver nano-rod/ITO surface" was obtained by electrodeposition. Surface-enhanced Raman scattering (SERS) spectrum of high quality of C60 and stearic acid (SA) mixed Langmuir-Blodgett (LB) film shifted onto the new substrate was reported for the first time according to our knowledge. The results show that the substrate of "gold nano-particle/silver nano-rod/ITO surface" is very effective and active for C60 LB film. Furthermore, the C60 molecules are oriented on pentagons of C60 on the substrate. It is difficult to separate the electromagnetic and chemical mechanisms to the great enhancement of the Raman signal. On the one hand, the gold nano-particles grown on silver nano-rod surface perform an important action for magnifying the surface local electric field through the resonant excitation of surface plasma. And the needle-like rod may further magnify the local electric field because of lightning rod effect. On the other hand, charge transfer factor may not be neglected.


Assuntos
Fulerenos/química , Análise Espectral Raman/métodos , Ácidos Esteáricos/química , Sítios de Ligação , Ouro/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Modelos Químicos , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Prata/química , Especificidade por Substrato , Ressonância de Plasmônio de Superfície , Propriedades de Superfície
13.
Zhong Yao Cai ; 29(1): 56-9, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16722321

RESUMO

In order to obtain the theoretical mass transfer model in the process of extracting effective ingredients from natural plant by Supercritical Fluid, the mass transfer mechanism was analyzed and the analytical solution of the dynamic model of Supercritical Fluid Extraction was deduced through rational simplifying the differential mass balance equations. The complete extraction time, extraction yield as a function of time and the influence of the diameter of solid material on the extraction yield were calculated by the model and the results of computation fit well with the experimental data of literature. This model can be used to analyze, predict, design and optimize the process of extracting effective ingredients from natural plant by Supercritical Fluid.


Assuntos
Cromatografia com Fluido Supercrítico , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Tecnologia Farmacêutica/métodos , Cinética , Matemática , Modelos Teóricos , Pressão , Temperatura , Tempo
14.
Chem Commun (Camb) ; (9): 1050-1, 2004 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-15116179

RESUMO

A novel halide sensor, which yields greater fluorescence upon binding to fluoride, has been synthesized and characterized.

15.
J Am Soc Mass Spectrom ; 14(5): 449-59, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12745214

RESUMO

Electrospray mass spectrometry (ES-MS) is an important tool for characterization of non-covalent binding in the gas phase. In this study, iron (II) has been introduced as a dication to enhance the detection of cyclodextrin (CD) plus aromatic compound complexes in ES-MS. Evidence that a novel ternary complex comprised of one beta-CD, one iron (II) and one toluene exists as an inclusion complex has been compiled via ES-MS and ES-MS/MS experiments as well as by a computational approach. This evidence strongly suggests that iron (II) serves to modify the conformation of the beta-CD ring, and that toluene inclusion is stabilized by dication interaction with the toluene pi-system and by crimping of the beta-CD ring leading to stronger van der Waals interactions with toluene. Mg(II), another dication of similar radius, showed similar behavior, while added group one cations (H(+) and Na(+)) were ineffective at producing observable ions representative of the complex. The ternary beta-CD complex with iron (II) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) has also been examined. ES-MS and ES-MS/MS experiments suggest that it is the polar portion of 2,4,5-T (i.e., the carboxylic acid moiety) that is favored for inclusion in the beta-CD cavity, rather than the non-polar aromatic part.


Assuntos
Ciclodextrinas/química , Gases/química , Espectrometria de Massas por Ionização por Electrospray , beta-Ciclodextrinas , Cátions Bivalentes/química , Ferro/química , Modelos Moleculares , Estrutura Molecular , Termodinâmica , Tolueno/química
16.
Sci Total Environ ; 307(1-3): 215-29, 2003 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-12711436

RESUMO

The effectiveness and selectivity of Fenton degradation of hydrophobic organic compounds (HOCs) can be improved by simultaneous complexation of Fe(2+) and the organic compound with a cyclodextrin or derivatized cyclodextrin. Such selective complexation of a target substrate and a catalytic metal is a crude mimic of enzyme systems. Both beta-cyclodextrin and carboxymethyl-beta-cyclodextrin (CMCD) were able to simultaneously complex Fe(2+) and an aromatic hydrocarbon, such as phenol, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls (PCBs). Degradation of compounds included in cyclodextrins was unaffected by hydroxyl radical scavengers, indicating that the radical was formed at the ternary complex (HOC-cyclodextrin-iron) and in close proximity to the included molecule. Without cyclodextrins, humic acid (HA) decreased degradation efficiency. However, in the presence of CMCD, HA did not inhibit degradation of the target compound. CMCD is capable of removing HOCs from HA binding sites while at the same time complexing Fe(2+). PCBs sorbed to glass were resistant to Fenton degradation, but were significantly degraded using a cyclodextrin modified Fenton system. In all of these systems, the ternary HOC-cyclodextrin-iron complexes effectively direct hydroxyl radical reaction toward the HOC, increasing the efficiency of Fenton degradation. One potential application of such targeted degradation systems is the in situ remediation of hydrophobic organic pollutants in contaminated soil and groundwater or in industrial waste streams.

17.
Ai Zheng ; 21(11): 1231-4, 2002 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12526222

RESUMO

BACKGROUND & OBJECTIVE: The up-regulation of mucin MUC1 expression or down-regulation of mucin MUC2 expression may be involved in carcinogenesis of some neoplasms, but there was few report about the relationship between mucin MUC1 and MUC2 expression and Chinese colorectal carcinoma. The aim of this study was to explore relationship between expression of mucin MUC1 and MUC2 in colorectal carcinoma and clinicopathological parameters and their clinical significance. METHODS: The expression of mucin MUC1 and MUC2 in 126 cases of colorectal carcinoma were detected by S-P immunohistochemical technique. RESULTS: The positive expression rates of mucin MUC1 and MUC2 in normal colorectal mucosa were 0 and 100%, respectively, but the positive expression rates of mucin MUC1 and MUC2 in 126 cases of colorectal carcinoma were 42.1% and 36.5%, respectively (P < 0.01); the expression of mucin MUC1 was positive correlated to the depth of invasion, lymph node metastasis, and Dukes staging (P < 0.05), but negative correlated to the degree of differentiation (P < 0.05); mucin MUC2 expression was related to invasion, lymph node metastasis, and Dukes staging (P < 0.05), but unrelated to differentiation (P > 0.05). CONCLUSIONS: The up-regulation of mucin MUC1 expression or down-regulation of mucin MUC2 expression may be involved in carcinogenesis and progression in colorectal carcinoma, and the detecting of mucin MUC1 and MUC2 may be predicting its prognosis in colorectal carcinoma.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Mucina-1/metabolismo , Mucinas/metabolismo , Neoplasias Retais/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Neoplasias do Colo/patologia , Feminino , Humanos , Mucosa Intestinal/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mucina-2 , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Retais/patologia
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