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1.
Clin Spine Surg ; 33(4): E185-E190, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31972570

RESUMO

STUDY DESIGN: This was a cross-sectional cohort study. OBJECTIVE: The objective of this study was to identify the prevalence of sleep disturbance in patients with symptomatic lumbar spinal stenosis (LSS) and to establish the relationship between sleep disturbance and both functional disability and health-related quality of life in patients with symptomatic LSS. SUMMARY OF BACKGROUND DATA: Despite the possible association between LSS and poor sleep quality, there has been no study regarding the relationship between LSS and sleep disturbance. MATERIALS AND METHODS: A total of 148 patients with LSS were divided into the poor sleeper and nonpoor sleeper groups according to Global Pittsburgh Sleep Quality Index (PSQI) score. Demographic data, Visual Analog Scale (VAS) score for back and leg pain, Oswestry Disability Index (ODI), and EuroQol 5-dimension questionnaire (EQ-5D) were compared between both groups. Multiple regression analysis was performed with ODI or ODI without sleep component as the dependent variable and age, sex, PSQI, VAS for back pain, VAS for leg pain as independent variables. RESULTS: Of the 148 patients who participated in this study, 54 (36.5%) and 94 (63.5%) patients were classified into nonpoor sleeper and poor sleeper groups. Although there were no differences in demographic data or VAS for back or leg pain between the nonpoor sleeper and poor sleeper groups, poor sleepers demonstrated significantly higher ODI scores, and lower EQ-5D than nonpoor sleepers (P=0.003 and 0.004, respectively). There were significant correlations between the global PSQI score and both the ODI score and EQ-5D. Although the surgical treatment group showed significantly higher VAS for back pain, VAS for leg pain, ODI scores, and lower EQ-5D than the conservative treatment group, the ratio of poor to nonpoor sleepers was not different between both groups (P=0.733). In the surgical treatment group, the percent of poor sleeper decreased from 65.1% to 47.6% 6 months after surgery (P<0.001). CONCLUSIONS: The present study demonstrated that 'poor sleep quality' is a prevalent condition (63.5%) in patients with symptomatic LSS. Poor sleep quality has an adverse effect on functional disability and health-related quality of life in symptomatic LSS patients.

2.
Spine J ; 20(2): 156-165, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31542473

RESUMO

BACKGROUND CONTEXT: Biportal endoscopic decompressive laminectomy is a widely performed procedure and shows acceptable clinical outcomes. However, the evidence regarding the advantages of biportal endoscopic surgery is weak, a randomized controlled trial is therefore warranted. PURPOSE: To compare the clinical efficacies of biportal endoscopic and microscopic decompressive laminectomy in patients with lumbar spinal stenosis. STUDY DESIGN: Randomized controlled trial. PATIENT SAMPLE: Sixty-four participants suffering from low back and leg pain with single-level lumbar spinal stenosis who required decompressive laminectomy. OUTCOME MEASURES: Outcomes were assessed with the use of patient-reported outcome measures, visual analog scale (VAS) score for low back and lower extremity radiating pain, Oswestry disability index (ODI), European Quality of Life-5 Dimensions (EQ-5D) score, and painDETECT for neuropathic pain. Surgery-related outcomes including operation time, length of hospital stay, postoperative drainage, and serum creatine phosphokinase were evaluated. Perioperative (<30 days) and late (1-12 months) complications were also noted. METHODS: All participants were randomly assigned in a 1:1 ratio to undergo biportal endoscopic or microscopic decompressive laminectomy. The primary outcome was the ODI score at 12 months after surgery based on a modified intention-to-treat strategy. The secondary outcomes included VAS score for low back and lower extremity radiating pain, ODI scores, EQ-5D score, and painDETECT score. There were no sources of funding and no conflicts of interest associated with this study. RESULTS: There was no significant difference between groups in the mean ODI score at 12 months after surgery (30 in the microscopy vs. 29 in the biportal endoscopy group, p=.635). There were also no significant differences in low back and lower extremity pain VAS scores, ODI, EQ-5D scores, and painDETECT scores at the 3-, 6-, or 12-month follow-up. Operation time, length of hospital stay, serum creatine phosphokinase, and perioperative complications, such as durotomies and symptomatic hematoma, showed no significant differences between the groups; however, one participant underwent additional revision surgery 9 months after the index surgery in the microscopy group. CONCLUSIONS: Despite the study design limitation of relatively short duration of follow-up, this trial suggests that biportal endoscopic decompressive laminectomy is an alternative to and offers similar clinical outcomes as microscopic open surgery in patients with symptomatic lumbar spinal stenosis.

3.
J Nanosci Nanotechnol ; 19(3): 1686-1689, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469246

RESUMO

Ternary oxide thin films in the In2O3-ZnO-SnO2 system were studied for potential applications in oxide semiconductor thin film transistors (TFTs). An amorphous In-Zn-Sn-O (a-IZTO) active channel layer was deposited by RF magnetron sputtering at room temperature on an n++ Si substrate. Films from a sintered ceramic target with a nominal chemical composition of In:Zn:Sn = 40:50:10 at.% were prepared with thicknesses ranging from 15 nm to 150 nm, which was followed by annealing at 350 °C for 30 minutes in air. Subsequently, a bilayer Cu/Ti metal contact was deposited as the source/drain electrodes on the top surface through a shadow mask using an e-beam evaporator. The thickness of the active channel layer greatly influenced the characteristics of the oxide thin film transistors. The best transistor characteristics were observed from the test device with a channel thickness of 30 nm and a high on/off current ratio of approximately 108, high field effect mobility of 25 cm²/Vs, low threshold voltage of -0.1 V, and very small subthreshold swing of 0.14 V/dec.

4.
Eur Spine J ; 27(11): 2804-2813, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30225536

RESUMO

PURPOSE: To translate and cross-culturally adapt the Core Outcome Measures Index (COMI) into the Korean language and to test the psychometric properties of the Korean COMI in patients with degenerative lumbar spine diseases. METHODS: A cross-cultural adaptation of the COMI into Korean was carried out using established guidelines. A total of 117 patients with lumbar spinal diseases were recruited from the spinal center of a tertiary care teaching institution and completed a baseline questionnaire including the newly translated COMI, the visual analog scale for back pain and for leg pain, the Oswestry Disability Index (ODI), and the EuroQOL-5 dimensions (EQ-5D). Within 2 weeks after the first assessment, 83 (71%) completed a second COMI questionnaire and a transition question (no change, slight change, moderate change, a lot of change) by phone to assess reproducibility. RESULTS: COMI summary scores displayed 1.7% floor effects and no ceiling effect. For construct validity, each COMI item and COMI summary score well correlated with its corresponding reference questionnaire. Therefore, the predefined hypotheses for the construct validities of each COMI item (ρ > 0.4 with the corresponding questionnaire) and the COMI summary score (ρ > 0.6 with both ODI and EQ-5D) were confirmed. Intraclass correlation coefficients of each COMI item and summary score ranged from 0.93 to 0.98. Therefore, the hypothesis for reliability (ICC > 0.8) was confirmed. CONCLUSIONS: The present study highlights that the Korean version of the COMI is a reliable and valid outcome tool for use in Korean-speaking patients with degenerative lumbar spinal disease. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Avaliação da Deficiência , Vértebras Lombares/fisiopatologia , Doenças da Coluna Vertebral , Inquéritos e Questionários/normas , Humanos , Reprodutibilidade dos Testes , República da Coreia , Doenças da Coluna Vertebral/classificação , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/fisiopatologia , Traduções
5.
Materials (Basel) ; 10(7)2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28773058

RESUMO

Top-contact bottom-gate thin film transistors (TFTs) with zinc-rich indium zinc tin oxide (IZTO) active layer were prepared at room temperature by radio frequency magnetron sputtering. Sintered ceramic target was prepared and used for deposition from oxide powder mixture having the molar ratio of In2O3:ZnO:SnO2 = 2:5:1. Annealing treatment was carried out for as-deposited films at various temperatures to investigate its effect on TFT performances. It was found that annealing treatment at 350 °C for 30 min in air atmosphere yielded the best result, with the high field effect mobility value of 34 cm2/Vs and the minimum subthreshold swing value of 0.12 V/dec. All IZTO thin films were amorphous, even after annealing treatment of up to 350 °C.

6.
Qual Life Res ; 26(12): 3323-3330, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28776287

RESUMO

PURPOSE: Firstly, to investigate the prevalence of frailty and impact on health-related quality of life (HRQOL) in a Korean community-dwelling elderly population using the Fried frailty criteria; secondly, to investigate the associations among frailty, socioeconomic status (SES), and HRQOL of the Korean community-based population; and thirdly, to analyze the relationship between education, income, and frailty. METHODS: Nine hundred and sixty-four apparently heathy subjects from the Korean community-based population were enrolled in this prospective cross-sectional study. Using self-reported questionnaires, demographic data, SES, and HRQOL were evaluated. Frailty status was determined according to the Fried frailty criteria. After adjustment of covariates including age, sex, and BMI, multivariate linear regression analyses were conducted to assess each component of the proposed mediation models, and mediation was also verified by the bootstrapping technique. RESULTS: Among the 964 participants, 530 (55.0%), 399 (41.4%), and 35 (3.6%) participants were classified into the robust, pre-frailty, and frailty group, respectively. The frail group demonstrated significantly lower HRQOL. Participants with lower income or education level had significantly higher chances of being frail. Frailty acted as a mediator in this association between low SES (education and income) and low HRQOL. Furthermore, income contributed most to the explanation of educational differences in frailty, suggesting full mediation. CONCLUSION: Frailty has a significant negative influence on HRQOL in the community-based elderly population, and acts as a mediator between SES and HRQOL. As a mediator, income can explain educational difference related with the frailty.


Assuntos
Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/métodos , Qualidade de Vida/psicologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Renda , Vida Independente , Coreia (Geográfico) , Masculino , Estudos Prospectivos , Classe Social , Inquéritos e Questionários
7.
ACS Appl Mater Interfaces ; 8(33): 21787-97, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27463945

RESUMO

We introduce a simple process for the fabrication of SiO2 films embedded with ß-Sn-rich nano/microspheres. Sn spheres with maximum and minimum sizes of 10 µm (near the SiO2 surface) and 5 nm (at the Si/SiO2 interface) were grown within a 0.7-5.7 µm-thick SiO2 layer by evaporating SnO powders onto an Si (100) substrate for 1-600 min at 600-900 °C and 0.001-5.0 Torr. A possible growth mechanism of these materials is discussed. The current-voltage characteristics of the as-fabricated samples were investigated to identify potential applications. During these tests, small flashes of light and the presence of damaged areas were observed at the oxide surfaces of the samples using an optical camera and a field emission scanning electron microscope, respectively. The electrical breakdown and shutdown of the devices observed in the current-voltage curves were attributed to the destruction of the SiO2 surface. In addition, the current-time responses show that the size of the damaged regions can be controlled by the voltage and duration of the applied stress, and are independent of the size and shape of the electrodes. The present materials thus possess great potential for applications in self-destructing devices.

8.
J Nanosci Nanotechnol ; 15(1): 241-3, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328339

RESUMO

We have embedded a TiO2 nanoparticle (NP) photoelectrode in a Ti substrate to improve the cell efficiency of conventional TiO2 NP based dye-sensitized solar cells (DSSCs) using Ti substrate. Compared to the conventional standing-type (TiO2 NPs on Ti substrate) DSSCs, the embedded-type (TiO2 NPs embedded in Ti substrate) DSSCs have shown an approximately 35% improvement in power conversion efficiency due to the improvement of J(sc). The embedded-type DSSCs have more charge transport paths than do standing-type DSSCs due to the increase of contact area between the TiO2 NP sidewall and the Ti substrate. This increased contact area decreases the electrical resistance and increases the charge collection efficiency, which leads to the improvement of J(sc). The embedded-type NP-DSSCs are very effective DSSC structures for enhancing the power conversion efficiency of Ti substrate based DSSCs.

9.
J Nanosci Nanotechnol ; 15(10): 7845-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26726426

RESUMO

We have studied the effect of TiCl4 post-treatment on the embedded-type TiO2 nanotubes (NT)-dye-sensitized solar cells (DSSCs). The TiO2 nanoparticles layer formed on TiO2 NTs surface by TiCl4 post-treatment showed different morphologies depending on TiCl4 treatment temperature. These different morphologies influenced the cell efficiency of TiO2 NT-DSSCs. The TiO2 NT treated with TiCl4 at 50 °C exhibited a rougher surface than that treated at 70 °C. The rough surface of the TiO2 NT improved the charge exchange between the dye and electrolyte. The TiO2 NT treated with TiCl4 at 50 °C showed better fill factor and cell efficiency than that treated at 70 °C. The TiCl4 post-treatment of TiO2 NT was effective at conditions of low temperature and long times. The TiO2 NT-DSSCs with TiCl4 post-treatment at 50 °C for 1.5 h showed an efficiency of 6.52%.

10.
J Nanosci Nanotechnol ; 14(10): 7961-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25942902

RESUMO

Transmission electron microscopy (TEM) analyses were performed to examine the spontaneously ordered structure in single crystals of 3.2 mole% of Y2O3 added ZrO2 (3.2 YSZ) manufactured by the Skull melting method. The selected area electron diffraction patterns showed several super-structure reflections with symmetrical intensity at (100), (010), and (110) positions, indicating that Y0.5Zr0.5O(2-x) with L1(0)-like cation-ordered structure was formed in 3.2 YSZ. High-resolution TEM has been used to reveal the presence of the partially ordered structure, which was characterized by a doublet periodicity in the contrast of the {100} lattice planes.

11.
J Nanosci Nanotechnol ; 14(12): 9020-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25971002

RESUMO

The growth of ZnO nanorods on the c-plane of Al2O3 substrates by PLD was been investigated by controlling processing conditions such as growth temperature, distance between target and substrate, and background oxygen pressure. ZnO nanorods were observed from the growth temperature of 600 degrees C for the oxygen pressure of 30 mTorr and the target/substrate distance of 70 mm. The diameters of the ZnO nanorods at the temperature of 700 degrees C and the oxygen pressure of 30 mTorr were approximately 200, 70, and 40 nm for the distance of 45, 70, and 100 mm, respectively. ZnO films without nanorods were observed at the distance of 70 mm and the temperature of 700 degrees C when the oxygen pressure decreased to 1 mTorr. The kinetic energy of the ablated particles by the laser decreases during collisions with background oxygen molecules, resulting in conditions that favor the growth of ZnO nanorods.

12.
J Nanosci Nanotechnol ; 12(4): 3264-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22849102

RESUMO

We investigated the size-dependent electrical conductivities of indium zinc oxide stripes with different widths from 50 nm to 4 microm and with the same thickness of 50 nm deposited by RF magnetron sputtering. The size of the indium zinc oxide stripes was controlled by e-beam lithography. The distance of the two Ti/Au Ohmic electrodes along the indium zinc oxide stripes was kept constant at 25 microm. The electrical conductivity decreased as the size of the indium zinc oxide stripes decreased below a critical width (80 nm). The activation energy, derived from the electric conductivity versus temperature measurement, was dependent on the dimensions of indium zinc oxide stripes. These results can be understood as stemming from surface charge trapping from the absorption of oxygen and/or water vapor, which leads to an increase in the energy difference between the conduction energy band and the Fermi energy.

13.
J Nanosci Nanotechnol ; 12(2): 1415-20, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22629969

RESUMO

ZnO nanowires were grown on indium tin oxide (ITO) coated glass substrates at a low temperature of 90 degrees C using an aqueous solution method. The ZnO seeds were coated on the ITO thin films by using a spin coater. ZnO nanowires were formed in an aqueous solution containing zinc nitrate hexahydrate (Zn(NO3)2 x 6H2O) and hexamethylenetetramine (C6H12N4). The pH value and concentration of the solution play an important role in the growth and morphologies of ZnO nanowires. The size of ZnO naonowires increased as the concentration of the solution increased. It was formed with a top surface of hexagonal and tapered shape at low and high pH values respectively. Additionally, the single crystalline structure and optical property of the ZnO nanowires were investigated using high-resolution transmission electron microscopy and photoluminescence spectroscopy.

14.
J Nanosci Nanotechnol ; 8(1): 99-110, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18468056

RESUMO

A brief review is given of recent developments in wide bandgap semiconductor nanowire synthesis and devices fabricated on these nanostructures. There is strong interest in these devices for applications in UV detection, gas sensors and transparent electronics.

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