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1.
Nano Lett ; 23(6): 2277-2286, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36913627

RESUMEN

Colloidal nanocrystals (NCs) have shown remarkable promise for optoelectronics, energy harvesting, photonics, and biomedical imaging. In addition to optimizing quantum confinement, the current challenge is to obtain a better understanding of the critical processing steps and their influence on the evolution of structural motifs. Computational simulations and electron microscopy presented in this work show that nanofaceting can occur during nanocrystal synthesis from a Pb-poor environment in a polar solvent. This could explain the curved interfaces and the olivelike-shaped NCs observed experimentally when these conditions are employed. Furthermore, the wettability of the PbS NCs solid film can be further modified via stoichiometry control, which impacts the interface band bending and, therefore, processes such as multiple junction deposition and interparticle epitaxial growth. Our results suggest that nanofaceting in NCs can become an inherent advantage when used to modulate band structures beyond what is traditionally possible in bulk crystals.

2.
J Shoulder Elbow Surg ; 32(2): 340-347, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36279988

RESUMEN

BACKGROUND: This retrospective study compared the outcomes after open and arthroscopic treatment of chronic medial epicondylitis (ME). METHODS: The study included 44 elbows in 38 patients: 25 (29-72 years) in the open group and 19 (27-70 years) in the arthroscopy group. The indications for ME surgery were failed conservative therapy for more than 3 months, symptom duration exceeding 6 months, and persistent severe pain. We used radiography, ultrasonography, and magnetic resonance imaging assessments. The clinical assessment included operating time, range of motion, grip strength, visual analog scale (VAS) score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and complications. RESULTS: The mean follow-up was 20.2 (12-58) months. The mean operating time was significantly longer in the arthroscopy group (32.5 vs. 23.5 minutes; P = .029). In both groups, all outcome measures improved significantly after surgery and there were no significant differences between the DASH scores (preoperative 44.8 vs. 43.9, postoperative 12.5 vs. 13.2), grip strength (preoperative 72.2 vs. 66.8, postoperative 84.8 vs. 83.6), and VAS scores (preoperative 8.5 vs. 8.2, postoperative 1.0 vs. 1.1) in the open and arthroscopy groups. The outcomes were excellent or good in 20 patients (80%) in the open group and 16 (84%) in the arthroscopy group. The only complication was 1 case of transient ulnar neuropathy in the open group. CONCLUSION: Open and arthroscopic techniques were very effective and comparable for treating chronic ME. The surgeon can choose either technique for treating chronic ME.


Asunto(s)
Tendinopatía del Codo , Codo de Tenista , Humanos , Estudios Retrospectivos , Desbridamiento/métodos , Codo de Tenista/cirugía , Artroscopía/métodos , Resultado del Tratamiento
3.
Nano Lett ; 21(23): 9909-9915, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34843258

RESUMEN

While the orientation-dependent properties of semiconductor nanowires have been theoretically predicted, their study has long been overlooked in many fields owing to the limits to controlling the crystallographic growth direction of nanowires (NWs). We present here the orientation-controlled growth of single-crystalline germanium (Ge) NWs using a self-catalytic low-pressure chemical vapor deposition process. By adjusting the growth temperature, the orientation of growth direction in GeNWs was selectively controlled to the ⟨110⟩, ⟨112⟩, or ⟨111⟩ directions on the same substrate. The NWs with different growth directions exhibit distinct morphological features, allowing control of the NW morphology from uniform NWs to nanoribbon structures. Significantly, the VLS-based self-catalytic growth of the ⟨111⟩ oriented GeNW suggests that NW growth is possible for single elementary materials even without an appropriate external catalyst. Furthermore, these findings could provide opportunities to investigate the orientation-dependent properties of semiconductor NWs.

4.
Arthroscopy ; 37(4): 1117-1125, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33307149

RESUMEN

PURPOSE: To biomechanically characterize superior capsule reconstruction (SCR) using fascia lata allograft, double-layer dermal allograft, and single-layer dermal allograft for a clinically relevant massive irreparable rotator cuff tear involving the entire supraspinatus and 50% of the infraspinatus tendons. METHODS: Eight cadaveric specimens were tested in 0°, 30°, and 60° abduction for (1) intact, (2) massive rotator cuff tear, (3) SCR using fascia lata, (4) SCR using double-layer dermis, and (5) SCR using single-layer dermis. Superior translation and subacromial contact pressure were measured. Statistical analysis was conducted using repeated measures ANOVA or paired t test with P < .05. RESULTS: Massive rotator cuff tear significantly increased superior translation of the humeral head at all abduction angles (P < .05). At 0° abduction, all SCR conditions significantly decreased superior translation compared with the massive tear but did not restore translation (P < .05) to intact. Fascia lata and double-layer dermis SCR restored superior translation to intact at 30° and 60° of abduction, but single-layer dermis did not. Subacromial contact pressure at 0° of abduction significantly decreased with SCR with fascia lata and double-layer dermis compared with tear. At 30°, all SCR conditions significantly decreased subacromial contact pressure. Single-layer dermis graft thickness significantly decreased more than fascia lata during testing (P = .02). CONCLUSION: For SCR tensioned at 20° glenohumeral abduction, all 3 graft types may restore superior translation and subacromial contact pressure depending on the glenohumeral abduction angle; fascia lata and double-layer dermis may be more effective than single-layer dermis. CLINICAL RELEVANCE: If a dermal graft is to be used for SCR, consideration should be given to doubling the graft for increased thickness and better restorative biomechanical properties, which may improve clinical outcomes following SCR.


Asunto(s)
Aloinjertos/trasplante , Dermis/trasplante , Fascia Lata/trasplante , Procedimientos de Cirugía Plástica , Anciano , Fenómenos Biomecánicos , Fascia Lata/fisiopatología , Humanos , Cabeza Humeral/fisiopatología , Cabeza Humeral/cirugía , Masculino , Persona de Mediana Edad , Presión , Rango del Movimiento Articular , Articulación del Hombro/fisiopatología , Articulación del Hombro/cirugía , Trasplante Homólogo
5.
J Korean Med Sci ; 32(2): 352-356, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28049249

RESUMEN

This prospective intervention study was undertaken to estimate the prevalence and treatment rate of osteoporosis following osteoporosis screening tests in the same cohort. From November 1, 2014 to August 31, 2015, participants received screening tests for osteoporosis using ultrasound bone densitometry and education concerning osteoporosis and related conditions. The participants were interviewed using a questionnaire on the diagnosis and initiation of osteoporosis treatment during the follow-up period. Of 960 potential participants, 595 people (68.8%; 150 men and 445 women) were given bone densitometry measurements and completed the questionnaire. The mean age of the participants was 74.0 years. Of the 595 participants, 393 people (66.1%; 67 men and 326 woman) were diagnosed with osteoporosis (T score < -2.5). The prevalence of osteoporosis showed an increasing trend, from 48.1% in 2004 to 66.1% in 2015. Of the 393 participants diagnosed with osteoporosis, 65 participants received additional bone densitometry measurements while hospitalized and osteoporosis management was re-initiated in 44 patients. The osteoporosis management rate in the study cohort increased from 21.6% to 32.8%, with osteoporosis diagnosed in 66.2% of participants at the latest follow-up. This prospective intervention study demonstrated that a screening test and an educational brochure increased the treatment rate from 21.6% to 32.8%.


Asunto(s)
Osteoporosis/diagnóstico , Anciano , Anciano de 80 o más Años , Densidad Ósea , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Osteoporosis/epidemiología , Prevalencia , Estudios Prospectivos , Encuestas y Cuestionarios , Ultrasonografía
6.
J Hand Surg Am ; 42(12): 1029.e1-1029.e8, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28807347

RESUMEN

PURPOSE: To define the role of the dorsal capsule and associated dorsal fibrocartilage (DFC) and their interactions with the radial collateral ligament (RCL) as a thumb metacarpophalangeal (MCP) joint stabilizer. METHODS: Eight cadaveric thumbs were mounted onto a custom jig with 20 N of muscle load applied. The thumb position in space was digitized to measure ulnar-radial, pronation-supination, and volar-dorsal laxity at 0°, 30°, and 60° MCP joint flexion. Serial sectioning was performed and measurements were repeated for the intact state, proper RCL insufficiency, proper and accessory (complete) RCL insufficiency, complete RCL with 50% DFC (radial) insufficiency, and complete RCL with complete DFC insufficiency. RESULTS: Ulnar-radial deviation, pronation-supination, and volar-dorsal translation significantly changed at 30° and 60° MCP joint flexion when comparing complete RCL insufficiency with complete RCL with 50% DFC insufficiency. At 30° flexion, significant increases were found in ulnar deviation, pronation, and volar translation, and there was a decrease in supination. At 60° flexion, ulnar deviation, pronation, and volar translation increased and radial deviation decreased significantly. At 30° flexion, the resting position significantly pronated and translated volarly. At 60° flexion, the resting position significantly shifted ulnarly, pronated, and translated volarly. CONCLUSIONS: The DFC acts as a secondary stabilizer of the thumb MCP joint, working in tandem with the RCL. It acts by stabilizing the MCP joint dorsoradially when external forces are applied across the joint. This cadaveric study shows that RCL insufficiency with a concomitant DFC injury is less likely to be stable than RCL injuries alone, and that this effect is more pronounced with MCP joint flexion. CLINICAL RELEVANCE: Increasing incompetence of the secondary stabilizers of the RCL, such as the DFC, will likely result in increased clinical instability upon physical examination. The results of this study also suggest the need to consider repair of the DFC at the time of RCL repair.


Asunto(s)
Inestabilidad de la Articulación/etiología , Articulación Metacarpofalángica/fisiopatología , Pulgar , Anciano , Cadáver , Ligamentos Colaterales/fisiopatología , Femenino , Fibrocartílago/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Pronación/fisiología , Rango del Movimiento Articular/fisiología , Supinación/fisiología , Articulación de la Muñeca/fisiopatología
7.
Circ J ; 80(11): 2336-2342, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27666598

RESUMEN

BACKGROUND: Some disagreements surround the effects of calcium-channel blockers (CCBs) on the risk of dementia. The purpose of this study was to investigate the protective effects of CCBs on dementia among elderly hypertensive Koreans.Methods and Results:We conducted a large population-based cohort study using the senior cohort database of the Korean National Health Insurance Service (2002-2013). Subjects were elderly hypertensive Koreans older than 60 years of age. A total of 18,423 patients (CCB user group: 13,692 patients; non-CCB antihypertensive user group: 4,731 patients) were statistically analyzed using the Cox proportional hazard regression model to estimate the adjusted hazard ratio (aHR) and confidence intervals (CIs) of dementia associated with CCB use. There were 2,881 cases (21.0%) of dementia in the CCB user group and 1,124 cases (23.8%) in the non-user group. CCB use significantly reduced the risk of total dementia (aHR 0.81, 95% CI 0.75-0.87, P<0.0001), Alzheimer's dementia (aHR 0.80, 95% CI 0.72-0.88, P<0.0001), and vascular dementia (aHR 0.81, 95% CI 0.70-0.94, P=0.0067). CONCLUSIONS: CCB use had a protective effect on the risk of dementia among elderly hypertensive Koreans. (Circ J 2016; 80: 2336-2342).


Asunto(s)
Enfermedad de Alzheimer/epidemiología , Bloqueadores de los Canales de Calcio/administración & dosificación , Demencia Vascular , Hipertensión , Programas Nacionales de Salud , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/prevención & control , Estudios de Cohortes , Demencia Vascular/epidemiología , Demencia Vascular/prevención & control , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Masculino , República de Corea , Factores de Riesgo
8.
J Korean Med Sci ; 31(1): 61-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26770039

RESUMEN

Several published studies have reported the need to change the cutoff points of anthropometric indices for obesity. We therefore conducted a cross-sectional study to estimate anthropometric cutoff points predicting high coronary heart disease (CHD) risk in Korean adults. We analyzed the Korean National Health and Nutrition Examination Survey data from 2007 to 2010. A total of 21,399 subjects aged 20 to 79 yr were included in this study (9,204 men and 12,195 women). We calculated the 10-yr Framingham coronary heart disease risk score for all individuals. We then estimated receiver-operating characteristic (ROC) curves for body mass index (BMI), waist circumference, and waist-to-height ratio to predict a 10-yr CHD risk of 20% or more. For sensitivity analysis, we conducted the same analysis for a 10-yr CHD risk of 10% or more. For a CHD risk of 20% or more, the area under the curve of waist-to-height ratio was the highest, followed by waist circumference and BMI. The optimal cutoff points in men and women were 22.7 kg/m(2) and 23.3 kg/m(2) for BMI, 83.2 cm and 79.7 cm for waist circumference, and 0.50 and 0.52 for waist-to-height ratio, respectively. In sensitivity analysis, the results were the same as those reported above except for BMI in women. Our results support the re-classification of anthropometric indices and suggest the clinical use of waist-to-height ratio as a marker for obesity in Korean adults.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/patología , Adulto , Anciano , Antropometría , Área Bajo la Curva , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Obesidad/patología , Curva ROC , República de Corea , Factores de Riesgo , Circunferencia de la Cintura , Relación Cintura-Cadera , Adulto Joven
9.
J Korean Med Sci ; 29(7): 995-1000, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25045234

RESUMEN

The purpose of this study was to predict osteoporosis risk as decreasing muscle mass and to declare the cut-off value of low muscle mass in an elderly Korean population. This study was based on data from the 2008-2010 Korea National Health and Nutritional Examination Surveys (KNHANES). The subjects included 1,308 men and 1,171 women over 65 yr. Bone mineral density (BMD) and appendicular skeletal muscle (ASM) were measured by dual energy X-ray absorptiometry (DXA), and appendicular skeletal muscle was adjusted by height as a marker of sarcopenia. After confirming the correlation between low muscle mass and BMD, the best cut-off value of muscle mass to estimate osteoporosis was suggested through the receiver operating characteristic (ROC) curve. For both men and women, BMD correlated positively with low muscle mass when ASM/Ht(2) was used as a marker for sarcopenia. The ROC curve showed that ASM/Ht(2) was the best marker for osteoporosis at a cut-off value of 6.85 kg/m(2) for men and 5.96 kg/m(2) for women. When these cut-off values were used to determine sarcopenia, the risk of osteoporosis increased 4.14 times in men and 1.88 times in women. In particular, men (OR 2.12) with sarcopenia were more greatly affected than women (OR 1.15), even after adjusting for osteoporosis risk factors. In elderly Korean people, sarcopenia is positively correlated with BMD and there is a strong correlation between sarcopenia and osteoporosis with risk of bone fracture.


Asunto(s)
Músculo Esquelético/patología , Osteoporosis/diagnóstico , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Pueblo Asiatico , Índice de Masa Corporal , Densidad Ósea , Femenino , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagen , Encuestas Nutricionales , Oportunidad Relativa , Osteoporosis/etiología , Curva ROC , República de Corea , Factores de Riesgo , Sarcopenia/fisiopatología
10.
Eur J Appl Physiol ; 113(8): 2159-66, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23615823

RESUMEN

We tested the hypothesis that acute inflammation may cause arterial stiffening in older adults. We further explored if high cardiorespiratory fitness may partially prevent the unfavorable effect of arterial stiffening produced by acute systemic inflammation in older adults. Using a randomized double-blind sham placebo-controlled design, forty healthy older adults were assigned to receive either an influenza vaccine or a sham vaccine. C-reactive protein and interleukin 6 (IL-6) were measured as markers of inflammation. Carotid-femoral pulse wave velocity (PWV) and augmentation index (AIX) as indices of arterial stiffness and wave reflection were assessed at baseline and 24 and 48 h after each vaccination. When compared with sham placebo, the influenza vaccination caused a significant increase in CRP (p < 0.05) and IL-6 (p < 0.05). Carotid-femoral PWV, but not AIX was significantly increased after influenza vaccination (p < 0.05), but not sham vaccination. The high cardiorespiratory fitness group had an attenuated increase in PWV as compared to the low cardiorespiratory fitness group after acute inflammation (p < 0.05). These findings show that acute inflammation may cause significant increases in arterial stiffness in older adults, but these increases were attenuated in the high cardiorespiratory fitness group as compared to the low cardiorespiratory fitness group.


Asunto(s)
Reacción de Fase Aguda/fisiopatología , Frecuencia Cardíaca , Consumo de Oxígeno , Aptitud Física , Rigidez Vascular , Reacción de Fase Aguda/etiología , Factores de Edad , Anciano , Proteína C-Reactiva/análisis , Arterias Carótidas/fisiopatología , Método Doble Ciego , Prueba de Esfuerzo , Femenino , Arteria Femoral/fisiopatología , Humanos , Vacunas contra la Influenza/inmunología , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso , Vacunación/efectos adversos
11.
J Shoulder Elbow Surg ; 22(11): 1469-73, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24007649

RESUMEN

BACKGROUND: We evaluated the clinical outcome and findings of ligamentous repair for acute posterolateral rotatory instability (PLRI) of the elbow. MATERIALS AND METHODS: Nineteen patients underwent lateral collateral ligament repair for acute PLRI. Ten male and nine female patients were observed for a mean of 9 months; their mean age was 46 years (14-70 years). The mean time from injury to operation was 8.1 days (1-18 days). The lateral pivot shift and varus stress test results were positive for all cases. We repaired the lateral ulnar collateral ligament with Ethibond in 6 cases and Bio-FASTak in 15 cases. We evaluated the range of motion, pain, and stability by the satisfaction of the patient, the Mayo Elbow Performance Score, and the Nestor grading. RESULTS: The lateral pivot shift test result was negative in all patients at the final follow-up. The mean elbow extension was 13°; flexion, 120°; supination, 74°; and pronation, 78°. Mild valgus laxity was noted in two patients who had mild pain on activity. The mean Mayo Elbow Performance Score was 86.9 points (65-100 points), with 13 excellent cases, 5 good cases, and 1 fair case. According to the Nestor grading, the results were rated excellent in 14 patients and good in 5. All patients were satisfied with their outcome in the subjective assessment. The complications were 1 case of knot irritation and 5 cases of ectopic ossification. CONCLUSION: We obtained satisfactory outcomes with lateral collateral ligament repair for acute PLRI of the elbow.


Asunto(s)
Ligamentos Colaterales/cirugía , Articulación del Codo/cirugía , Luxaciones Articulares/cirugía , Inestabilidad de la Articulación/cirugía , Adolescente , Adulto , Anciano , Ligamentos Colaterales/lesiones , Codo , Femenino , Humanos , Inestabilidad de la Articulación/etiología , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Rotura , Adulto Joven , Lesiones de Codo
12.
Nano Lett ; 12(8): 4007-12, 2012 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-22823001

RESUMEN

We report on the catalytic growth of thin carbon sheathed single crystal germanium nanowires (GeNWs), which can solve the obstacles that have disturbed a wide range of applications of GeNWs. Single crystal Ge NW core and amorphous carbon sheath are simultaneously grown via vapor-liquid-solid (VLS) process. The carbon sheath completely blocks unintentional vapor deposition on NW surface, thus ensuring highly uniform diameter, dopant distribution, and electrical conductivity along the entire NW length. Furthermore, the sheath not only inhibits metal diffusion but also improves the chemical stability of GeNWs at even high temperatures.

13.
Arch Orthop Trauma Surg ; 133(7): 1029-32, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23604791

RESUMEN

Closed flexor tendon ruptures due to trauma without external wound are rare. When the flexor tendon has excessive loading, failure occurs at the tendon insertion or its origin from the bone. It is likely to result in avulsion fracture rather than rupture of the proper portion of the tendon by forceful grasping with hyperextension. However, we have experienced three cases of closed flexor tendon ruptures at zone V, caused by forceful grasping or hyperextension mechanism against resistance. On physical examination, these patients could not flex interphalangeal joint of thumb or distal interphalangeal joint of the fifth finger. All patients underwent MRI or ultrasonography to find out the location of loss in continuity of the flexor tendons before the operation. After identifying the location, flexor tendon repair or tendon graft using palmaris longus were performed.


Asunto(s)
Traumatismos de los Tendones/etiología , Traumatismos de los Tendones/cirugía , Articulación de la Muñeca/cirugía , Anciano , Diagnóstico por Imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rotura , Traumatismos de los Tendones/diagnóstico , Ultrasonografía , Articulación de la Muñeca/diagnóstico por imagen
14.
Orthopedics ; : 1-6, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37921526

RESUMEN

This study compared the results of endoscopic cubital tunnel release (eCuTR) with those of open cubital tunnel release (oCuTR) for the management of cubital tunnel syndrome (CuTS). In this retrospective study, 35 patients underwent eCuTR or oCuTR. Group I and group II consisted of 16 patients undergoing eCuTR and 19 patients undergoing oCuTR, respectively. Patients were asked to report paresthesia and pain, and electromyography was performed. The Dellon and Bishop classifications were used. The Disabilities of the Arm, Shoulder and Hand (DASH) and visual analog scale (VAS) pain scores were recorded, as well as the key pinch strength and two-point discrimination. The incision length and operation duration were noted. The mean follow-up was 39 months. The mean operating time was longer in the endoscopy group (43 vs 22 minutes). Overall, 34.3% (n=12) of the cases were classified as Dellon grade II and 65.7% (n=23) were classified as Dellon grade III. According to the Bishop score, excellent or good results were obtained for 75% of the patients in the eCuTR group and 78.9% of the patients in the oCuTR group. In the eCuTR and oCuTR groups, all outcome measures improved after surgery: DASH score (preoperative, 37.7 vs 30.7; postoperative, 15.4 vs 20), VAS score (preoperative, 7.8 vs 7.3; postoperative, 4.3 vs 4.1), pinch strength (preoperative, 74 vs 66; postoperative, 93 vs 84), and two-point discrimination (preoperative, 5.6 vs 6.6; postoperative, 4.9 vs 4.5). No significant difference was apparent between the two techniques in outcomes. However, the endoscopic release had a higher reoperation rate and took twice as long to perform despite having a shorter incision. [Orthopedics. 202x;4x(x):xx-xx.].

15.
Nanomaterials (Basel) ; 13(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36770552

RESUMEN

The roll-to-roll (R2R) gravure process has the potential for manufacturing single-wall carbon nanotubes (SWCNT)-based thin film transistor (TFT) arrays on a flexible plastic substrate. A significant hurdle toward the commercialization of the R2R-printed SWCNT-TFT array is the lack of a suitable, simple, and rapid method for measuring the uniformity of printed products. We developed a probing instrument for characterizing R2R gravure printed TFT, named PICR2R-TFT, for rapidly characterizing R2R-printed SWCNT-TFT array that can present a geographical distribution profile to pinpoint the failed devices in an SWCNT-TFT array. Using the newly developed PICR2R-TFT instrument, the current-voltage characteristics of the fabricated SWCNT-TFT devices could be correlated to various R2R-printing process parameters, such as channel length, roll printing length, and printing speed. Thus, by introducing a characterization tool that is reliable and fast, one can quickly optimize the R2R gravure printing conditions to enhance product uniformity, thereby maximizing the yield of printed SWCNT-TFT arrays.

16.
Ann Geriatr Med Res ; 27(3): 241-249, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37635674

RESUMEN

BACKGROUND: This study aimed to identify the risk factors associated with coronavirus disease 2019 (COVID-19) infection and mortality among older adults in South Korea. METHODS: Using Korean National Health Insurance data from January 1, 2020, to March 31, 2022, we analyzed the impact of various factors, including age, comorbidity burden, and insurance type, on COVID-19 infection and mortality rates. RESULTS: Age was the most significant risk factor for mortality in older adults. A higher comorbidity burden was also associated with increased infection (odds ratio [OR]=1.33 for Charlson Comorbidity Index [CCI] ≥2, 95% confidence interval [CI] 1.321-1.339) and mortality (OR=1.537 for CCI ≥2, 95% CI 1.459-1.618) rates. While Medical Aid recipients exhibited lower infection rates (OR=0.898, 95% CI 0.89-0.906) than National Health Insurance beneficiaries, they had higher mortality rates (OR=1.692, 95% CI 1.623-1.763). CONCLUSION: These results emphasized the need to prioritize vaccination and allocate healthcare resources for older adults, particularly those with multiple comorbidities. Addressing socioeconomic disparities and ensuring equitable access to testing and healthcare services are crucial for mitigating the impact of COVID-19 on older adults.

17.
J Nanosci Nanotechnol ; 12(5): 4103-7, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22852353

RESUMEN

The crystalline germanium nanowires (GeNWs) with a uniform graphitic carbon shell were prepared via a conventional low-pressure chemical vapor deposition method without any external catalyst. The GeNWs grown at low temperature (Tg < 500 degrees C) have a uniform diameter with a large expect ratio of more than 10(3). With increasing the growth temperature (Tg > 500 degrees C), however, the nanowire morphology is dramatically changed into a hybrid structure where highly dense Ge nanoparticles (GeNPs) with a diameter of 5-10 nm are attached onto the Ge nanowires. The nanostructures consist of crystalline Ge-core and very thin graphitic carbon shell. The possible mechanism of anisotropic growth and the control of morphological transition from uniform nanowires to NW/NP hybrid structures are discussed and demonstrated.

18.
Ann Geriatr Med Res ; 26(3): 264-274, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36200291

RESUMEN

BACKGROUND: Sarcopenia, a progressive and generalized skeletal muscle disorder involving an accelerated loss of muscle mass and muscle function, is a common condition in older individuals. This study aimed to determine whether sleep latency and duration were independently associated with incident sarcopenia and to explore sex differences in these associations. METHODS: This 2-year longitudinal analysis of cohort study data included community-dwelling participants of the 2016-2017 Korea Frailty and Aging Cohort Study aged 70-84 years at baseline survey who completed the 2-year follow-up survey. Logistic regression was used to calculate the odds ratios (ORs) for sarcopenia and sarcopenia components. Sarcopenia was defined using the 2019 Asian Working Group for Sarcopenia guidelines. RESULTS: Among 1,353 non-sarcopenic participants in the baseline survey, 1,160 (85.8%) and 193 (14.2%) were classified as non-sarcopenic and sarcopenic, respectively, after 2 years. Long sleep duration (>8 hours per night) was associated with incident sarcopenia in male-OR=2.41 (95% confidence interval [CI], 1.13-5.17) after adjusting for confounding factors. Long sleep duration was specifically associated with the development of low skeletal muscle mass and low muscle strength in male-adjusted OR=2.16 (95% CI, 1.02-4.61) and adjusted OR=2.70 (95% CI, 1.13-6.43), respectively. In female, compared to normal sleep duration, the adjusted ORs for long and short sleep duration for sarcopenia were 2.093 (95% CI, 0.753-5.812; p=0.157) and 0.852 (95% CI, 0.520-1.393; p=0.522), respectively, which were not significant. CONCLUSION: In male, long sleep duration was associated with incident sarcopenia, specifically the development of low muscle mass and low muscle strength, but not with low physical performance.

19.
Orthopedics ; 45(6): e326-e334, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35947456

RESUMEN

We evaluated the outcomes of precontoured locking plate fixation with the anconeus flap transolecranon (AFT) approach to treating AO type C2-3 comminuted intra-articular distal humerus (IDH) fractures among active patients. Thirty-six patients (age <65 years) with IDH fractures treated with precontoured distal humerus locking plate fixation were divided into 2 groups: group 1 (n=18; transolecranon [TO] approach) and group 2 (n=18; AFT approach). The radiographic examination included assessments of implant failure, fracture site union, and olecranon osteotomy site union. Clinical examination included assessments of operating time, range of motion (ROM), Mayo Elbow Performance Score (MEPS), Disability of the Arm, Shoulder and Hand (DASH) score, and complications. The mean follow-up time was 25.2 months (range, 18-79 months). The mean operating time was 134.3 minutes and was significantly longer for group 2 (AFT; 141.2 minutes) than for group 1 (TO; 124.2 minutes). The mean olecranon osteotomy site union time was significantly longer in group 2 (7.4 weeks) than in group 2 (4.0 weeks). Olecranon osteotomy site resorption occurred among 6 of 18 patients only in group 2. No significant difference in ROM (flexion, 130°; extension, -0.7°), MEPS (85.7 points), DASH score (20.0 points), or frequency of major complications (TO, 5; AFT, 6) was observed between the groups. Our results showed no advantage of the AFT approach over the TO approach, despite preserving the anconeus. Prospective randomized trials will be necessary to compare the AFT and TO approaches for treating comminuted IDH fractures. [Orthopedics. 2022;45(6):e326-e334.].


Asunto(s)
Articulación del Codo , Fracturas Conminutas , Fracturas del Húmero , Humanos , Anciano , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/cirugía , Fracturas del Húmero/etiología , Codo , Fijación Interna de Fracturas/métodos , Estudios Prospectivos , Resultado del Tratamiento , Articulación del Codo/diagnóstico por imagen , Articulación del Codo/cirugía , Húmero , Fracturas Conminutas/cirugía , Rango del Movimiento Articular , Estudios Retrospectivos
20.
ACS Appl Mater Interfaces ; 14(11): 13499-13506, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35274921

RESUMEN

Electronic devices in highly integrated and miniaturized systems demand electromagnetic interference shielding within nanoscale dimensions. Although several ultrathin materials have been proposed, satisfying various requirements such as ultrathin thickness, optical transparency, flexibility, and proper shielding efficiency remains a challenge. Herein, we report an ultrahigh electromagnetic interference (EMI) SSE/t value (>106 dB cm2/g) using a conductive CuS nanosheet with thickness less than 20 nm, which was synthesized at room temperature. We found that the EMI shielding efficiency (EMI SE) of the CuS nanosheet exceeds that of the traditional Cu film in the nanoscale thickness, which is due to high conductivity and the presence of internal dipole structures of the CuS nanosheet that contribute to absorption due to the damping of dipole oscillation. In addition, the CuS nanosheet exhibited high mechanical stability (104 cycles at 3 mm bending radius) and air stability (25 °C, 1 atm), which far exceeded the performance of the Cu nanosheet film. This remarkable performance of nanometer-thick CuS proposes an important pathway toward designing EMI shielding materials for wearable, flexible, and next-generation electronic applications.

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