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1.
BMC Musculoskelet Disord ; 25(1): 639, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39134982

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the long-term consequences on the cervical spine after Anterior transcorporeal percutaneous endoscopy cervical discectomy (ATc-PECD) from the biomechanical standpoint. METHODS: A three-dimensional model of the normal cervical spine C2-T1 was established using finite element method. Subsequently, a disc degeneration model and degeneration with surgery model were constructed on the basis of the normal model. The same loading conditions were applied to simulate flexion, extension, lateral bending and axial rotation of the cervical spine. We calculated the cervical range of motion (ROM), intradiscal pressure, and intravertebral body pressure under different motions for observing changes in cervical spine biomechanics after surgery. At the same time, we combined the results of a long-term follow-up of the ATc-PECD, and used imaging methods to measure vertebral and disc height and cervical mobility, the Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) score were used to assess pain relief and neurological functional recovery. RESULTS: The long-term follow-up results revealed that preoperative JOA score, neck VAS score, hand VAS score, IDH, VBH, and ROM for patients were 9.49 ± 2.16, 6.34 ± 1.68, 5.14 ± 1.48, 5.95 ± 0.22 mm, 15.41 ± 1.68 mm, and 52.46 ± 9.36° respectively. It changed to 15.71 ± 1.13 (P < 0.05), 1.02 ± 0.82 (P < 0.05), 0.77 ± 0.76 (P < 0.05), 4.73 ± 0.26 mm (P < 0.05), 13.67 ± 1.48 mm (P < 0.05), and 59.26 ± 6.72° (P < 0.05), respectively, at 6 years postoperatively. Finite element analysis showed that after establishing the cervical spondylosis model, the overall motion range for flexion, extension, lateral bending, and rotation decreased by 3.298°, 0.753°, 3.852°, and 1.131° respectively. Conversely, after establishing the bone tunnel model, the motion range for these actions increased by 0.843°, 0.65°, 0.278°, and 0.488° respectively, consistent with the follow-up results. Moreover, analysis of segmental motion changes revealed that the increased cervical spine mobility was primarily contributed by the surgical model segments. Additionally, the finite element model demonstrated that bone tunneling could lead to increased stress within the vertebral bodies and intervertebral discs of the surgical segments. CONCLUSIONS: Long-term follow-up studies have shown that ATc-PECD has good clinical efficacy and that ATc-PECD can be used as a complementary method for CDH treatment. The FEM demonstrated that ATc-PECD can lead to increased internal stresses in the vertebral body and intervertebral discs of the operated segments, which is directly related to cervical spine degeneration after ATc-PECD.


Asunto(s)
Vértebras Cervicales , Discectomía Percutánea , Endoscopía , Análisis de Elementos Finitos , Desplazamiento del Disco Intervertebral , Rango del Movimiento Articular , Humanos , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/fisiopatología , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Estudios de Seguimiento , Discectomía Percutánea/métodos , Endoscopía/métodos , Masculino , Persona de Mediana Edad , Adulto , Femenino , Descompresión Quirúrgica/métodos , Resultado del Tratamiento , Fenómenos Biomecánicos , Degeneración del Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/diagnóstico por imagen
2.
Artículo en Inglés | MEDLINE | ID: mdl-38639611

RESUMEN

Objective: The objective of this study was to enhance the efficiency of pre-check and triage procedures in gynecology and obstetrics, while ensuring the safety of maternal and infant patients during the COVID-19 pandemic. Methods: Between March 2020 and July 2022, the workflow in gynecology and obstetrics was optimized, and the management of medical staff working in outpatient, ward, and obstetric ward settings was strengthened. Special protocols were developed and implemented for pregnant women, parturients, and neonates. Detailed procedures and routes were established for patient movement from outpatient areas to wards, with strict adherence to pandemic prevention and control measures. Information-based methods were employed to track and monitor the health status of high-risk pregnant women, parturients, and their families, facilitating accurate and efficient pre-check and triage processes. Results: The implementation of these measures yielded favorable outcomes. No cases of COVID-19 infection were reported among pregnant women and parturients admitted to Liangzhou Hospital. The source of infection was effectively controlled, ensuring the safety of the patients. Conclusion: This study demonstrates the significance of improving pre-check and triage efficiency, strengthening the management of medical staff, and implementing specialized measures for pregnant women, parturients, and neonates to ensure their safety during the COVID-19 pandemic. The established protocols and procedures can serve as a valuable reference for other healthcare facilities seeking to enhance their pandemic prevention and control strategies in gynecology and obstetrics settings.

3.
J Sci Food Agric ; 102(1): 241-249, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34081336

RESUMEN

BACKGROUND: Half of all apple production worldwide comes from China. However, the geographic authentication of Chinese apples has not been well studied. We highlight the multi-element-based geographical discrimination of apples from the southwest cold highlands (SCH) of China. 565 samples from the SCH (138) and others (427) were obtained, and the content of fifteen elements were applied to construct models for discrimination. RESULTS: The SCH apples from 2017 to 2019 had higher concentrations of Mn, Zn, Cr, Cd, Se, Pb, and Fe, but lower concentrations of Na, B, Ni, and P. With sufficient training, linear discriminant analysis (LDA) discriminated the SCH, and the testing accuracy averaged 92.5% and 92.2%. Nonlinear discrimination models were more suitable than the linear models. Optimized random forest analysis was the model with the best fit, and with averaged training and testing it obtained a level of accuracy of 98.2% and 98.5%. CONCLUSION: The multielement-based discrimination of SCH apples could aid further studies of geographical origins. © 2021 Society of Chemical Industry.


Asunto(s)
Frutas/química , Malus/química , Oligoelementos/análisis , China , Análisis Discriminante , Frutas/clasificación , Malus/clasificación
4.
Front Psychol ; 12: 768293, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35058841

RESUMEN

Previous corporate social responsibility (CSR) studies at the employee level have focused on the influence of CSR on employees' positive attitudes and behavior. However, little attention has been paid to the relationship between CSR and unethical behavior and the underlying mechanism. Based on social information processing theory, this study investigates how CSR affects employee cheating via employees' organizational identification and perceived supervisor moral decoupling. Additionally, this study discusses the moderating effect of employee bottom-line mentality on these relationships. We test this two-path model using a sample of MBA students in China. The results indicate that both organizational identification and perceived supervisor moral decoupling mediate the relationship between CSR and cheating, and employee bottom-line mentality moderates the effect of CSR on perceived supervisor moral decoupling. Specifically, for employees low in bottom-line mentality, CSR has a significantly negative impact on perceived supervisor moral decoupling, but the same relationship is insignificant for employees with a strong bottom-line mentality. Overall, our results uncover the relationship between CSR and employee cheating and extend the understanding of the influence of CSR on employees.

5.
J Sci Food Agric ; 99(14): 6182-6190, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31250438

RESUMEN

BACKGROUND: Apples from different regions of China show different qualities and internal characteristics, and appeal to different customers. However, these aspects have not been studied in depth. We characterized the profiles of 14 elements in 317 apple samples collected from five regions of China. Principal component analysis (PCA), linear discriminant analysis (LDA), and back-propagation artificial neural networks analysis (BP-ANN) were used to build models for apple authentication. RESULTS: Fourteen elements were successfully identified in apple samples by performing graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) analyses. Comparative analysis showed significantly different element profiles in samples from different regions. The first five principal components obtained by PCA accounted for 71.8% of the total variance. The LDA obtained 70.0% classification rates. The BP-ANN obtained 82.7% classification rates. CONCLUSION: This study indicated the possibility that apples could be authenticated based on differences in their element profiles, and provided a basis for further geographical origin studies. © 2019 Society of Chemical Industry.


Asunto(s)
Malus/química , Oligoelementos/química , China , Análisis Discriminante , Frutas/química , Frutas/clasificación , Malus/clasificación , Análisis de Componente Principal , Espectrofotometría Atómica
6.
Artículo en Inglés | MEDLINE | ID: mdl-29236072

RESUMEN

Environmental regulators often use environmental policy to induce green investment by firms. However, if an environmental policy fails to exert a long-run effect on regulating the economic agents' behavior, it may be more reasonable to think of the firm as the leader in the game, since the investment in green technology is usually a strategic decision. In this paper, we consider a three-stage Stackelberg game to address the interaction between a profit-maximizing firm (Stackelberg leader) facing emission-dependent demand, and the environmental regulator (Stackelberg follower). The firm decides on the green technology level in the first stage of the game based on its understanding of the regulator's profits function, especially an environmental concern that is introduced as an exogenous variable. In the current research, we show that high levels of the regulator's environmental concerns do not necessarily lead to the choice of green technology by the firm, and green investment level depends on the combined effects of the market and operational factors for a given level of the regulator's environmental concerns. The result also shows that increasing environmental awareness amongst the consumers is an effective way to drive the firm's green investment.


Asunto(s)
Política Ambiental/economía , Inversiones en Salud/economía , Modelos Económicos
7.
Langmuir ; 28(40): 14470-5, 2012 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-22989080

RESUMEN

We present the employment of the Keggin ion 12-phosphotungstic acid as a UV-switchable reducing agent for the decoration of Au, Ag, Pt, and Cu nanoparticles onto the surface of TiO(2) nanotubes synthesized by electrochemical anodization. The synthesized composites were studied using SEM, GADDS XRD, and EDX, and the photocatalytic activity of the composites was examined by measuring the photodegradation of the organic dye "Congo red" under simulated solar light. Decoration with metal nanoparticles was observed to enhance the activity of the photocatalytic process by upward of 100% with respect to unmodified TiO(2) nanotubes.


Asunto(s)
Nanopartículas del Metal/química , Nanotecnología/métodos , Nanotubos/química , Procesos Fotoquímicos , Titanio/química , Compuestos de Tungsteno/química , Rayos Ultravioleta , Catálisis , Electroquímica , Ácido Fosfotúngstico/química , Sustancias Reductoras/química
8.
ACS Nano ; 6(5): 4045-53, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22512314

RESUMEN

Here, we demonstrate that niobium pentoxide (Nb(2)O(5)) is an ideal candidate for increasing the efficiencies of dye-sensitized solar cells (DSSCs). The key lies in developing a Nb(2)O(5) crisscross nanoporous network, using our unique elevated temperature anodization process. For the same thicknesses of ∼4 µm, the DSSC based on the Nb(2)O(5) layer has a significantly higher efficiency (∼4.1%) when compared to that which incorporates a titanium dioxide nanotubular layer (∼2.7%). This is the highest efficiency among all of the reported photoanodes for such a thickness when utilizing back-side illumination. We ascribe this to a combination of reduced electron scattering, greater surface area, wider band gap, and higher conduction band edge, as well as longer effective electron lifetimes.

9.
Langmuir ; 26(24): 19148-52, 2010 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-21077615

RESUMEN

In research on alternative photoanode materials for dye-sensitized solar cells (DSCs), there is rarely any report on WO(3), probably due to its acidic surface and more positive (vs NHE) conduction band edge position compared to TiO(2) and ZnO. For the first time, dye-sensitized solar cells based on porous WO(3) nanoparticle films were successfully fabricated with efficiency of up to 0.75%. The multicrystalline structure of WO(3) was examined by Raman spectroscopy and X-ray diffraction analysis. It was found that significant performance enhancement can be obtained from treating the WO(3) nanoparticle film with TiCl(4); the TiCl(4)-treated WO(3) DSCs were recorded with efficiency reaching 1.46%.

10.
Langmuir ; 25(16): 9545-51, 2009 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-19627158

RESUMEN

Anodization at elevated temperatures in nitric acid has been used for the production of highly porous and thick tungsten trioxide nanostructured films for photosensitive device applications. The anodization process resulted in platelet crystals with thicknesses of 20-60 nm and lengths of 100-1000 nm. Maximum thicknesses of approximately 2.4 microm were obtained after 4 h of anodization at 20 V. X-ray diffraction analysis revealed that the as-prepared anodized samples contain predominantly hydrated tungstite phases depending on voltage, while films annealed at 400 degrees C for 4 h are predominantly orthorhombic WO3 phase. Photocurrent measurements revealed that the current density of the 2.4 microm nanostructured anodized film was 6 times larger than the nonanodized films. Dye-sensitized solar cells developed using these films produced 0.33 V and 0.65 mA/cm2 in open- and short-circuit conditions.

11.
Langmuir ; 25(1): 509-14, 2009 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-19053619

RESUMEN

We have investigated several key aspects for the self-organization of nanotubes in RF sputtered titanium (Ti) thin films formed by the anodization process in fluoride-ion-containing neutral electrolytes. Ti films were deposited on indium tin oxide (ITO) glass substrates at room temperature and 300 degrees C, and then anodized. The films were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis spectrometry before and after anodization. It was observed that anodization of high temperature deposited films resulted in nanotube type structures with diameters in the range of 10-45 nm for an applied voltage of 5-20 V. In addition, the anatase form of TiO(2) is formed during the anodization process which is also confirmed using photocurrent measurements. However, the anodization of room temperature deposited Ti films resulted in irregular pores or holes.

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