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1.
J Environ Radioact ; 280: 107522, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39270424

RESUMEN

To address the lack of effective dose quantification methods for the model organism Caenorhabditis elegans (C. elegans) in radiation ecology research, this study employs remeshing techniques to develop a comprehensive mesh-type model covering multi-life stages, from embryonic to larval (L1, L2, L3, L4) and adulthood. Using these models, Dose Coefficients (DC) for C. elegans in a soil environment under different exposure conditions (external and internal), material settings, and radioactive nuclides (³H, 6°Co, 9°Sr, 129I, 1³1I, 1³4Cs, 1³7Cs) were calculated with the Monte Carlo toolkit Geant4. The results show that the difference in DC, when C. elegans material is set as either biological material or water, is within 5%. Under external exposure conditions, the impact of life stages on the population's average DC is minimal (with a maximum deviation not exceeding 10%). However, the distribution within the population varied significantly across life stages (under external exposure to 137Cs, the dispersion was 12.02% for adults and a considerably higher 60.30% for larvae). The earlier the life stage, the greater the variability in DC distribution within the C. elegans population. Furthermore, correlation analysis indicates a strong relationship between DC and life stages under internal exposure scenarios. The mesh-type model of C. elegans established in this study provides a valuable tool for radiation ecology research and has potential applications in broader research fields.

2.
Front Psychol ; 15: 1387288, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39144584

RESUMEN

Background: In the medical field, effective time management by clinical nurses is crucial for enhancing the quality of patient care. However, in recent years, with increasing work pressure for clinical nurses, procrastination has become a prevalent issue. Many nurses use smartphones as a way to alleviate stress and manage emotions, but excessive smartphone use could exacerbate procrastination, thereby jeopardizing patient safety and healthcare quality. Therefore, understanding the current state of work procrastination among clinical nurses, its heterogeneity, and exploring the impact of smartphone addiction and demographic factors on different aspects of nurse procrastination hold significant importance for improving patient care quality. Objective: This study aims to explore the current state of work procrastination among clinical nurses and identify potential profile categories. It further analyzes the impact of mobile phone addiction and demographic factors on work procrastination among clinical nurses. Methods: Convenience sampling was employed to recruit participants from three tertiary hospitals in central China from October to November 2023. Surveys measuring nurses' work procrastination and smartphone addiction were distributed and collected through online platforms. A total of 1,536 nurses participated in this study. Mplus 8.3 statistical software was used for latent profile analysis of clinical nurses' work procrastination, and SPSS 26.0 software was utilized for chi-square tests, rank-sum tests, and multi-classification logistic regression analyses. Results: The median total score for clinical nurses' work procrastination was 21.00 (17.00, 28.00), and three subgroups were identified: low procrastination (66.93%), medium-low procrastination (20.66%), and medium-high procrastination (12.41%). Additionally, logistic regression analysis revealed that smartphone addiction and department atmosphere were common influencing factors for medium-low and medium-high work procrastination. Hospitals with stricter management and nurses holding the position of head nurse were more likely to belong to the low work procrastination group. Nurses with higher incomes or those holding intermediate titles were more prone to medium-low work procrastination, while those experiencing career advancement difficulties were more likely to exhibit medium-high work procrastination (p < 0.05). Conclusion: Clinical nurses' work procrastination is generally at a medium-to-low level, with three subgroups identified: low procrastination, medium-low procrastination, and medium-high procrastination. Additionally, clinical nurses in surgical departments or those with intermediate titles exhibit higher levels of procrastination. Factors such as smartphone addiction, higher monthly income, tense departmental atmosphere, and unsuccessful career advancement are more likely to lead to work procrastination. Conversely, nurses in hospitals with strict management or those holding the position of head nurse exhibit lower levels of work procrastination. Therefore, nursing managers should pay close attention to the work procrastination behaviors of clinical nurses, actively monitor predictive factors among different groups, and provide psychological counseling and relevant training based on individual nurse circumstances. Additionally, it is also essential to focus on and improve departmental atmosphere and nurse smartphone addiction to enhance clinical nurses' work efficiency and reduce work procrastination.

3.
Front Neurol ; 15: 1360609, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38841701

RESUMEN

Background: Symptomatic intracranial in-stent restenosis (sISR) poses a major challenge in the management of cerebrovascular diseases, often requiring effective and safe treatment options. Objectives: This study aims to evaluate the efficacy and safety of paclitaxel-coated balloon (PCB) angioplasty for treating sISR. Methods: We conducted a retrospective analysis of five patients aged 49-74 years, who were treated with PCB angioplasty between January 2017 and June 2022. Treatment procedures included pre-operative digital subtraction angiography, antiplatelet therapy, and the use of the SeQuent Please balloon. Patients received aspirin and clopidogrel prior to and after the procedure. Results: The procedure achieved a 100% success rate. The degree of ISR was significantly reduced from an average pre-operative rate of 72±18.9% to a post-operative rate of 34±8.22%. Long-term follow-up showed that the majority of patients did not experience restenosis, confirming the long-term effectiveness of the treatment. Conclusions: PCB angioplasty demonstrates significant potential as an effective and safe treatment option for patients with sISR, especially those considered to be at high risk. This study supports further investigation into PCB angioplasty as a standard treatment for sISR.

4.
Accid Anal Prev ; 200: 107544, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493612

RESUMEN

Cycling crashes constitute a significant and rising share of traffic accidents. Consequently, exploring factors affecting cycling safety has become a priority for both governmental bodies and scholars. However, most existing studies have neglected the vision factors capable of quantitatively describing the city-level cycling environment. Moreover, they have relied on limited models that lack interpretability and fail to capture the spatial variations in the contribution of factors. To address these gaps, this research proposed a framework that used origin-destination-based cycling flow and vision factors generated from Google Street View images to identify the leading factors. It also employed the comparative Automatic Machine Learning and interpretable SHAP value-based geospatial analysis to explain each factor's contribution to the cycling crash risk, with a particular focus on the spatial variations in the influence of vision factors. The effectiveness of this framework was validated by a case study in Manhattan, which examined the leading risk factors of cycling crash rates at intersections. The results showed that the LightGBM model, with selected subsets of factors, outperformed other models. Through SHAP explanations of global feature importance, the study identified the proportion of road barriers, the proportion of open sky, and the number of visible trucks as the leading visual risk factors. Additionally, using SHAP-based geospatial analysis, the study revealed the local variations in the effects of these three factors and identified eight areas with higher cycling crash rates. Based on these findings, the study provided practical measures for a safer cycling environment in Manhattan.


Asunto(s)
Accidentes de Tránsito , Ciclismo , Humanos , Accidentes de Tránsito/prevención & control , Factores de Riesgo , Aprendizaje Automático , Seguridad
5.
Phys Med Biol ; 68(17)2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37578025

RESUMEN

Objective.In clinical proton therapy, the spread-out Bragg peak (SOBP) is commonly used to fit the target shape. Dose depositions at microscopic sites vary, even with a consistent absorbed dose (D) in SOBP. In the present study, monolayer mesh-type cell population models were developed for microdosimetric assessment at different SOBP depths.Approach.Normal human bronchial epithelial (BEAS-2B) and hepatocytes (L-O2) mesh-type cell models were constructed based on fluorescence tomography images of normal human cells. Particle transport simulation in cell populations was performed coupled with Monte Carlo software PHITS. The relationship between microdosimetry and macrodosimetry of SOBP at different depths was described by analyzing the microdosimetric indicators such as specific energyz,specific energy distributionfz,D,and relative standard deviationσz/z¯within cells. Additionally, the microdosimetric distributions characteristics and their contributing factors were also discussed.Main results.The microscopic dose distribution is strongly influenced by cellular size, shape, and material. The mean specific energyz¯of nucleus and cytoplasm in the cell population is greater than the overall absorbed dose of the cell population model (Dp), with a maximumz¯/Dpof 1.1. The cellular dose distribution is different between the BEAS-2B mesh-type model and its concentric ellipsoid geometry-type model, which difference inz¯is about 10.3% for the nucleus and about 7.5% for the cytoplasm with the SOBP depth of 15 cm. WhenD= 2 Gy, the maximumzof L-O2 nucleus reaches 2.8 Gy andσz/z¯is 5.1% at the mid-depth SOBP (16-18 cm); while the maximumzof the BEAS-2B nucleus reaches 2.2 Gy with only 2.7% ofσz/z¯.Significance.The significant variation of microdosimetric distributions of SOBP different depths indicates the necessity to use mesh-type cell population models, which have the potential to be compared with biological results and build the bio-physical model.


Asunto(s)
Terapia de Protones , Protones , Humanos , Radiometría/métodos , Simulación por Computador , Programas Informáticos , Método de Montecarlo , Efectividad Biológica Relativa
6.
Radiat Res ; 200(2): 176-187, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37410090

RESUMEN

The mesh-type models are superior to voxel models in cellular dose assessment coupled with Monte Carlo codes. The aim of this study was to expand the micron-scale mesh-type models based on the fluorescence tomography of real human cells, and to investigate the feasibility of these models in the application of various irradiation scenarios and Monte Carlo codes. Six different human cell lines, including pulmonary epithelial BEAS-2B, embryonic kidney 293T, hepatocyte L-02, B-lymphoblastoid HMy2.CIR, Gastric mucosal GES-1, and intestine epithelial FHs74Int, were adopted for single mesh-type models reconstruction and optimization based on laser confocal tomography images. Mesh-type models were transformed into the format of polygon mesh and tetrahedral mesh for the GATE and PHITS Monte Carlo codes, respectively. The effect of model reduction was analyzed by dose assessment and geometry consideration. The cytoplasm and nucleus doses were obtained by designating monoenergetic electrons and protons as external irradiation, and S values with different "target-source" combinations were calculated by assigning radioisotopes as internal exposure. Four kinds of Monte Carlo codes were employed, i.e., GATE with "Livermore," "Standard" and "Standard and Geant4-DNA mixed" models for electrons and protons, as well as PHITS with "EGS" mode for electrons and radioisotopes. Multiple mesh-type real human cellular models can be applied to Monte Carlo codes directly without voxelization when combined with certain necessary surface reduction. Relative deviations between different cell types were observed among various irradiation scenarios. The relative deviation of nucleus S value reaches up to 85.65% between L-02 and GES-1 cells by 3H for the "nucleus-nucleus" combination, while that of 293T and FHs74Int nucleus dose for external beams at a 5.12 cm depth of water is 106.99%. Nucleus with smaller volume is far more affected by physical codes. There is a considerable deviation for dose within BEAS-2B at the nanoscale. The multiple mesh-type real cell models were more versatile than voxel models and mathematical models. The present study provided several models which can easily be extended to other cell types and irradiation scenarios for RBE estimations and biological effect predictions, including radiation biological experiments, radiotherapy and radiation protection.


Asunto(s)
Simulación por Computador , Método de Montecarlo , Humanos , Protones , Radioisótopos , Radiometría/métodos
7.
Int J Health Plann Manage ; 38(5): 1435-1452, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37316978

RESUMEN

AIMS: The inconsistent findings on the impact of the long-term care insurance (LTCI) system on family care require us to extend our study horizon to more countries with LTCI system designs or market practices. China has explored the LTCI system through pilot programs, which provide a quasi-natural experimental environment. This paper aims to examine how the LTCI system affects family care in China. METHODS: We primarily employ the time-varying difference-in-differences method to perform regression analyses based on the panel data from the China Health and Retirement Longitudinal Study. RESULTS: We discover a 7.2% rise in family care under the LTCI system. Specifically, the LTCI system is more likely to promote family care as the relatively primary care for disabled women, disabled people aged 60-74, and those who cannot fully take care of themselves. In addition, the formal care support policy of LTCI will crowd in both formal care and family care, and the crowding-in-effect on formal care may even obscure the crowding-in-effect on family care. The family care support policy of LTCI may encourage the policy-covered groups to take family care as their relatively primary care. It may also lengthen family care for those groups. CONCLUSIONS: The LTCI system has a crowding-in effect on family care. It can increase family care through cash payments or linking formal and informal care resources by providing formal community and home care.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Seguro de Cuidados a Largo Plazo , Humanos , Femenino , Estudios Longitudinales , Cuidados a Largo Plazo , China
8.
J Adv Nurs ; 79(10): 4008-4021, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37226654

RESUMEN

AIM: The purpose of this study was to explore the relationship between nurses' well-being and their ethical leadership, and the mediating role of workplace mindfulness in this relationship. DESIGN: This was a quantitative cross-sectional study. METHODS: This cross-sectional study was conducted in three tertiary hospitals in central China from May 2022 to July 2022, and the Nurses' Workplace Mindfulness, Ethical Leadership and Well-Being Scale were distributed and collected via the Internet. A total of 1579 nurses volunteered to participate in this study. SPSS 26.0 statistical software was used to analyse the data by Z-test and Spearman's rank correlation; the internal mechanism of workplace mindfulness and ethical leadership on nurses' well-being was completed by AMOS 23.0 statistical software. RESULTS: The scores of nurses' well-being, workplace mindfulness and ethical leadership were 93.00 (81.00, 108.00), 96.00 (80.00, 112.00) and 73.00 (67.00, 81.00) respectively. The professional title, age and department atmosphere affect their well-being. Spearman's analysis showed that nurses' well-being was positively correlated with ethical leadership (r = .507, p < .01) and workplace mindfulness (r = .600, p < .01); workplace mindfulness partially mediated the relationship between ethical leadership and nurses' well-being accounting for 38.5% of the total effect ratio [p < .001, 95% CI = (0.215, 0.316)]. CONCLUSION: Nurses' well-being was at a medium level, and had a higher score in ethical leadership and workplace mindfulness, and workplace mindfulness played a partial mediating role between ethical leadership and nurses' well-being. IMPACT: This suggests that nursing managers need to pay attention to clinical nurses' well-being experience, actively focus on the relationship among ethical leadership, workplace mindfulness and well-being and integrate core values such as positivity and morality into nurses' daily routines, so as to improve the work enthusiasm and well-being experience of clinical nurses, enhancing the nursing quality and stabilizing the nursing team.


Asunto(s)
Atención Plena , Enfermeras y Enfermeros , Personal de Enfermería en Hospital , Humanos , Liderazgo , Estudios Transversales , Actitud del Personal de Salud , Satisfacción en el Trabajo , Encuestas y Cuestionarios , Lugar de Trabajo
9.
Phys Med ; 101: 120-128, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35988482

RESUMEN

PURPOSE: The proximity function is an important index in microdosimetry for describing the spatial distribution of energy, which is closely related to the biological effects of organs or tissues in the target area. In this work, the impact of parameters, such as physic models, cut-off energy, and initial energy, on the proximity function are quantitated and compared. METHODS: According to the track structure (TS) and condensed history (CH) low-energy electromagnetic models, this paper chooses a variety of Monte Carlo (Monte Carlo, MC) codes (Geant4-DNA, PHITS, and Penelope) to simulate the track structure of low-energy electrons in liquid water and evaluates the influence of the electron initial energy, cut-off energy, energy spectrum, and physical model factors on the differential proximity function. RESULTS: The results show that the initial energy of electrons in the low-energy part (especially less than 1 keV) has a greater impact on the differential proximity function, and the choice of cut-off energy has a greater impact on the differential proximity function corresponding to small radius sites (generally less than 10 nm). The difference in the electronic energy spectrum has little effect on the result, and the proximity functions of different physics models show better consistency under large radius sites. CONCLUSIONS: This work comprehensively compares the differential proximity functions under different codes by setting a variety of simulation conditions and has basic guiding significance for helping users simulate and analyze the deposition characteristics of microscale electrons according to the selection of an appropriate methodology and cut-off energy.


Asunto(s)
Electrones , Agua , Simulación por Computador , Método de Montecarlo , Fenómenos Físicos , Agua/química
10.
Front Psychol ; 13: 915479, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35846639

RESUMEN

Background: Nurses' career success is an important factor affecting the quality of nursing services and the stability of the nursing workforce, and enhancing nurses' career success level is of key significance to the development of the nursing discipline. As psychological resilience and craftsmanship are important spiritual traits in the process of nurses' career development, it is important to understand the mechanism of their effects on nurses' career success level. Objective: To explore the current situation of craftsmanship, psychological resilience and career success levels of female nurses in central China, and to verify the mediating role of craftsmanship between psychological resilience and female career success using structural equation model. Methods: A cross-sectional study was conducted among 2359 female nurses from three hospitals in central China through an online questionnaire, including craftsmanship, psychological resilience and career success scale. The data were analyzed by Z-test and Spearman rank correlation with SPSS 23.0 statistical software, and the mechanism of the effect of craftsmanship and psychological resilience on career success was completed by AMOS 23.0 statistical software. Results: The scores of career success, psychological resilience, and craftsmanship of female nurses in central China were 68.00 (61.00, 75.00), 74.00 (64.00, 84.00), and 83.00 (79.00, 95.25). Spearman rank correlation analysis showed that Chinese female nurses' career success was positively correlated with craftsmanship (r = 0.511, P < 0.01) and psychological resilience (r = 0.595, P < 0.01). Craftsmanship played a mediating role between psychological resilience and career success, accounting for 39.3% of the total effect ratio. Conclusion: The scores of career success and psychological resilience of female nurses in central China are at a moderate level, and craftsmanship plays a mediating role between psychological resilience and career success. It is suggested that nursing managers should pay attention to the importance of career success to nurses' self-development and nursing team stability, and improve their sense of career success by effectively improving nurses' psychological resilience and craftsmanship.

11.
Ecotoxicol Environ Saf ; 225: 112770, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34536793

RESUMEN

Tritium is a water-soluble hydrogen isotope that releases beta rays during decay. In nature, tritium primarily exists as tritiated water (HTO), and its main source is nuclear power/processing plants. In recent decades, with the development of nuclear power industry, it is necessary to evaluate the impact of tritium on organisms. In this study, fertilized zebrafish embryos are treated with different HTO concentrations (3.7 × 103 Bq/ml, 3.7 × 104 Bq/ml, 3.7 × 105 Bq/ml). After treatment with HTO, the zebrafish embryos developed without evident morphological changes. Nevertheless, the heart rate increased and locomotor activity decreased significantly. In addition, RNA-sequencing shows that HTO can affect gene expressions. The differentially expressed genes are enriched through many physiological processes and intracellular signaling pathways, including cardiac, cardiovascular, and nervous system development and the metabolism of xenobiotics by cytochrome P450. Moreover, the concentrations of thyroid hormones in the zebrafish decrease and the expression of thyroid hormone-related genes is disordered after HTO treatment. Our results suggest that exposure to HTO may affect the physiology and behaviors of zebrafish through physiological processes and intracellular signaling pathways and provide a theoretical basis for ecological risk assessment of tritium.


Asunto(s)
Agua , Pez Cebra , Animales , Expresión Génica , Hidrógeno , Locomoción , Pez Cebra/genética
12.
J Environ Radioact ; 237: 106667, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34116456

RESUMEN

The release of liquid effluent of nuclear power into aquatic system increases with the rapid development of nuclear facilities in coastal and inland regions. Aquatic model animals are very important for the study of the radiation hazards to non-human biota in water environment and its extrapolation of dose-effect relationship to human models. However, the study of the radiation dose rate calculation model of the aquatic animal zebrafish is still on the homogeneous isotropic model used for the protection of the environment. A series of zebrafish models (including adults, larvae and embryos, named zebrafish-family: ZF-family) with multiple internal organs are established in this study to investigate the mechanism of radiation damage effect in order to protect non-human species. The internal and external dose coefficients (DCs) of the whole body, heart and gonads of zebrafishes are calculated in water environment with the combination of the real experimental culture condition, using Monte Carlo application package GATE (Geant4 Application for Emission Tomography) and eight nuclides, i.e., 3H, 14C, 90Sr, 60Co, 110mAg, 134Cs, 137Cs, 131I, which are commonly found in the liquid effluent of nuclear power plants, as the source items, The results show that the level of nuclide γ energy determines the external DCs (DCext), and 90Sr plays the most important role in internal DCs (DCint). The comparison between the external DCs of the heart and gonad and that of the whole body shows that DCs (DCext) of heart and gonad for females are 80% and 43% lower than that of whole body, respectively, while for males, the DCs (DCext) of heart is 44% lower than that of the whole body, and DCs (DCext) of gonad is slightly higher than that of the whole body for most nuclides (up to 25%).The dose of internal radiation makes greater contribution than that of external radiation to pure beta emitter (3H, 14C, 90Sr). This internal DCs of ZF-family model with complex internal structure turns out to demonstrate more sensitive DCs change trend and higher calculation values compared with the internal DCs of the simple ellipsoid model. In this model, the photon emitter with strong penetrating power has higher internal DCs, while the low-energy pure beta nuclide does not alter much. In conclusion, it is vital to carry out refined systematic modeling for model organisms, and the determination of DCs of model organs can promote the evaluation of the radiation effects on non-human species.


Asunto(s)
Monitoreo de Radiación , Pez Cebra , Animales , Femenino , Rayos gamma , Masculino , Método de Montecarlo , Fotones
13.
RSC Adv ; 8(57): 32922-32929, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-35547696

RESUMEN

A novel CeO2@CaO catalyst was prepared via a hydrothermal method. The physicochemical properties and morphologies of the prepared CeO2@CaO catalysts were characterized by X-ray diffraction, N2 physisorption, CO2 temperature-programmed desorption, X-ray photoelectron spectroscopy, transmission electron microscopy and energy dispersive X-ray analysis. It was found that the prepared CeO2@CaO catalyst had a distinct core-shell structure. The catalytic activity of the CeO2@CaO sample as a heterogeneous catalyst for the transesterification of soybean oil to produce biodiesel has been studied. The results showed that the optimum yield of biodiesel can reach 98% over the CeO2@CaO-60 catalyst under the reaction conditions of 3 wt% catalyst, methanol to oil molar ratio of 6 : 1, reaction temperature of 70 °C and reaction time of 6 h. Stability tests indicated that the biodiesel yield can reach more than 80% even after 9 reaction cycles due to the strong synergic interaction between CaO and CeO2.

14.
Artículo en Inglés | MEDLINE | ID: mdl-27293454

RESUMEN

Rannasangpei (RSNP) is used as a therapeutic agent in the treatment of cardiovascular diseases, neurological disorders, and neurodegeneration in China; however, its potential use in the treatment of vascular dementia (VD) was unclear. In this study, our aim was to examine the neuroprotective effect of RSNP in a VD rat model, which was induced by permanent bilateral common carotid artery occlusion (2VO). Four-week administration with two doses of RSNP was investigated in our study. Severe cognitive deficit in the VD model, which was confirmed in Morris water maze (MWM) test, was significantly restored by the administration of RSNP. ELISA revealed that the treatments with both doses of RSNP could reinstate the cholinergic activity in the VD animals by elevating the production of choline acetyltransferase (ChAT) and reducing the acetylcholinesterase (AChE); the treatment of RSNP could also reboot the level of superoxide dismutase (SOD) and decrease malondialdehyde (MDA). Moreover, Western blot and quantitative PCR (Q-PCR) results indicated that the RSNP could suppress the apoptosis in the hippocampus of the VD animals by increasing the expression ratio of B-cell lymphoma-2 (Bcl-2) to Bcl-2-associated X protein (Bax). These results suggested that RSNP might be a therapeutic agent in the treatment of vascular dementia in the future.

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