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1.
J Clin Med ; 13(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38731257

RESUMEN

Background/Objectives: Lumbar lordotic curvature (LLC), closely associated with low back pain (LBP) when decreased, is infrequently assessed in clinical settings due to the spatiotemporal limitations of radiographic methods. To overcome these constraints, this study used an inertial measurement system to compare the magnitude and maintenance of LLC across various sitting conditions, categorized into three aspects: verbal instructions, chair type, and desk task types. Methods: Twenty-nine healthy participants were instructed to sit for 3 min with two wireless sensors placed on the 12th thoracic vertebra and the 2nd sacral vertebra. The lumbar lordotic angle (LLA) was measured using relative angles for the mediolateral axis and comparisons were made within each sitting category. Results: The maintenance of LLA (LLAdev) was significantly smaller when participants were instructed to sit upright (-3.7 ± 3.9°) compared to that of their habitual sitting posture (-1.2 ± 2.4°) (p = 0.001), while the magnitude of LLA (LLAavg) was significantly larger with an upright sitting posture (p = 0.001). LLAdev was significantly larger when using an office chair (-0.4 ± 1.1°) than when using a stool (-3.2 ± 7.1°) (p = 0.033), and LLAavg was also significantly larger with the office chair (p < 0.001). Among the desk tasks, LLAavg was largest during keyboard tasks (p < 0.001), followed by mouse and writing tasks; LLAdev showed a similar trend without statistical significance (keyboard, -1.2 ± 3.0°; mouse, -1.8 ± 2.2°; writing, -2.9 ± 3.1°) (p = 0.067). Conclusions: Our findings suggest that strategies including the use of an office chair and preference for computer work may help preserve LLC, whereas in the case of cueing, repetition may be necessary.

2.
Micromachines (Basel) ; 14(6)2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37374812

RESUMEN

In this paper, we compared the characteristics of normally-on/off AlGaN/GaN MISHEMTs passivated by an in situ/ex situ SiN layer. The devices passivated by the in situ SiN layer revealed enhanced DC characteristics, such as the drain current of 595 mA/mm (normally-on) and 175 mA/mm (normally-off) with the high on/off current ratio of ~107, respectively, compared with those of the devices passivated by the ex situ SiN layer. The MISHEMTs passivated by the in situ SiN layer also exhibited a much lower increase of dynamic on-resistance (RON) of 4.1% for the normally-on device and 12.8% for the normally-off device, respectively. Furthermore, the breakdown characteristics are greatly improved by employing the in situ SiN passivation layer, suggesting that the in situ SiN passivation layer can remarkably not only suppress the surface-trapping effects, but also decrease the off-state leakage current in the GaN-based power devices.

3.
Ann Rehabil Med ; 46(4): 192-201, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36071001

RESUMEN

OBJECTIVE: To compare the biomechanical properties of the glenohumeral joint capsule between adhesive capsulitis (AC) after breast cancer surgery and idiopathic AC and demonstrate the effects of hydrodilatation (HD) with corticosteroid injection for AC after breast cancer surgery. METHODS: Twenty-three prospective patients with AC after breast cancer surgery (BC group) and 44 retrospective patients with idiopathic AC without breast cancer (CON group) underwent HD with corticosteroid injection and home exercise training. We compared their biomechanical characteristics (capsular capacity, maximal pressure, and capsular stiffness). In the BC group, the passive range of motion (ROM) of the affected shoulder and a questionnaire (Shoulder Pain and Disability Index [SPADI]) were evaluated at baseline and 2 and 4 weeks after treatment. RESULTS: The BC group showed higher biomechanical characteristics (maximal pressure and capsular stiffness) than did the CON group. The mean maximal pressure and capsular stiffness were 519.67±120.90 mmHg and 19.69±10.58 mmHg/mL in the BC group and 424.78±104.42 mmHg and 11.55±7.77 mmHg/mL in the CON group (p=0.002 and p=0.001, respectively). And, the BC group showed significant improvements in all ROMs (abduction, flexion, and external rotation) and the SPADI pain and disability sub-scores following the treatment. CONCLUSION: The glenohumeral joint capsular stiffness was greater in the patients with AC after breast cancer surgery than in those with idiopathic AC. HD with corticosteroid injection was effective in treating AC after breast cancer surgery.

4.
Adv Sci (Weinh) ; 9(29): e2203008, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35988149

RESUMEN

Individual carbon nanotubes (CNT) and graphene have unique mechanical and electrical properties; however, the properties of their macroscopic assemblies have not met expectations because of limited physical dimensions, the limited degree of dispersion of the components, and various structural defects. Here, a state-of-the-art assembly for a novel type of hybrid fiber possessing the properties required for a wide variety of multifunctional applications is presented. A simple and effective multidimensional nanostructure of CNT and graphene oxide (GO) assembled by solution processing improves the interfacial utilization of the components. Flexible GOs are effectively intercalated between nanotubes along the shape of CNTs, which reduces voids, enhances orientation, and maximizes the contact between elements. The microstructure is finely controlled by the elements content ratio and dimensions, and an optimal balance improves the mechanical properties. The hybrid fibers simultaneously exhibit exceptional strength (6.05 GPa), modulus (422 GPa), toughness (76.8 J g-1 ), electrical conductivity (8.43 MS m-1 ), and knot strength efficiency (92%). Furthermore, surface and electrochemical properties are significantly improved by tuning the GO content, further expanding the scope of applications. These hybrid fibers are expected to offer a strategy for overcoming the limitations of existing fibers in meeting the requirements for applications in the fiber industry.

5.
Sci Rep ; 12(1): 818, 2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-35039529

RESUMEN

Tendons have limited reparative ability and perform a relatively simple mechanical function via the extracellular matrix. Thus, the injured tendon might be treated successfully by stem cell transplantation. We performed a randomized, controlled study to investigate the effects of mesenchymal stem cell injection for treating partial tears in the supraspinatus tendon. We enrolled 24 patients with shoulder pain lasting more than 3 months and partial tears in the supraspinatus tendon. Participants were assigned to three groups: stem cells in fibrin glue, normal saline/fibrin glue mixture, and normal saline only, with which intra-lesional injection was performed. Pain at activity and rest, shoulder function and tear size were evaluated. For safety measures, laboratory tests were taken and adverse events were recorded at every visit. Participants were followed up at 6, 12 weeks, 6, 12 months and 2 years after injection. The primary outcome measure was the improvement in pain at activity at 3 months after injection. Twenty-three patients were included in the final analysis. Primary outcome did not differ among groups (p = 0.35). A mixed effect model revealed no statistically significant interactions. Only time significantly predicted the outcome measure. All participants reported transient pain at the injection site. There were no differences in post-injection pain duration or severity. Safety measures did not differ between groups, and there were no persistent adverse events. Stem cell injection into supraspinatus partial tears in patients with shoulder pain lasting more than 3 months was not more effective than control injections.ClinicalTrials.gov Identifier: NCT02298023.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas/métodos , Traumatismos de los Tendones/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Manguito de los Rotadores , Dolor de Hombro/etiología , Dolor de Hombro/terapia , Traumatismos de los Tendones/complicaciones , Resultado del Tratamiento
6.
Small Methods ; 5(8): e2100239, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34927877

RESUMEN

Despite considerable development in the field of single-atom catalysts (SACs) on carbon-based materials, the reported strategies for synthesizing SACs generally rely on top-down approaches, which hinder achieving both simple and universal synthesis routes that are simultaneously applicable to various metals and nanocarbons. Here, a universal strategy for fabricating nanocarbon based-SACs using a flash bottom-up arc discharge method to mitigate these issues is reported. The ionization of elements and their recombination process during arc discharge allows the simultaneous incorporation of single metal atoms (Mn, Fe, Co, Ni, and Pt) into the crystalline carbon lattice during the formation of carbon nanohorns (CNHs) and N-doped arc graphene. The coordination environment around the Co atoms of Co1 /CNH can be modulated by a mild post-treatment with NH3 . As a result, Co1 /CNH exhibits good oxygen reduction reaction activity, showing a 1.92 times higher kinetic current density value than the commercial Pt/C catalyst in alkaline media. In a single cell experiment, Co1 /CNH exhibits the highest maximum power density of 472 mW cm-2 compared to previously reported nonprecious metal-based SACs.

7.
Yonsei Med J ; 62(9): 868-871, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34427074

RESUMEN

Parsonage-Turner syndrome is a rare neurological disease of varying etiology characterized by severe shoulder pain, muscle weakness, and atrophy. Mechanisms are unclear, but are thought to be genetic and immune-mediated reactions. Rarely, Parsonage-Turner syndrome occurs as a side effect of vaccination. A 20-year-old male who worked as a soldier visited the military hospital because of shoulder pain after vaccination against typhoid and was diagnosed with Parsonage-Turner syndrome based on electromyography and joint magnetic resonance imaging. Pain was controlled with a nerve block. Intravenous immunoglobulin was administered for improvement of neurologic symptoms. This case suggests that Parsonage-Turner syndrome should be considered as a side effect of vaccination. To the best of our knowledge, this is the first report of Parsonage-Turner syndrome following vaccination in Korea.


Asunto(s)
Neuritis del Plexo Braquial , Fiebre Tifoidea , Adulto , Neuritis del Plexo Braquial/diagnóstico , Neuritis del Plexo Braquial/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Hombro , Fiebre Tifoidea/diagnóstico , Vacunación , Adulto Joven
8.
Osong Public Health Res Perspect ; 11(5): 334-338, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33117639

RESUMEN

This report describes the air evacuation of 80 Koreans from Iran to Korea on March 19th, 2020, with a direct transfer of passengers between airplanes in Dubai. The passengers were potentially infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) so, strict precautions were taken for the duration of the flight, and the passengers were screened before embarking from Dubai and disembarking at Incheon International Airport in Korea. Passengers with fever or symptoms of SARS-CoV-2 were assessed by a quarantine doctor, and if they were suspected of being infected with SARS-CoV-2, they were categorized as a "patient under investigation (PUI)". There was 1 passenger designated as a PUI before the departure from Dubai and another designated as a PUI upon arrival into Korea. The first PUI tested negative, but the second PUI tested positive for SARS-CoV-2. All those aboard the flight (passengers, aircrew, and medical staff) were screened for SARS-CoV-2 upon arrival into Korea and completed a mandatory 14-day medical quarantine. There were no additional cases of infection.

10.
Sensors (Basel) ; 18(5)2018 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-29695112

RESUMEN

The AlInN/GaN high-electron-mobility-transistor (HEMT) indicates better performances compared with the traditional AlGaN/GaN HEMTs. The present work investigated the pH sensor functionality of an analogous HEMT AlInN/GaN device with an open gate. It was shown that the Al0.83In0.17N/GaN device demonstrates excellent pH sense functionality in aqueous solutions, exhibiting higher sensitivity (−30.83 μA/pH for AlInN/GaN and −4.6 μA/pH for AlGaN/GaN) and a faster response time, lower degradation and good stability with respect to the AlGaN/GaN device, which is attributed to higher two-dimensional electron gas (2DEG) density and a thinner barrier layer in Al0.83In0.17N/GaN owning to lattice matching. On the other hand, the open gate geometry was found to affect the pH sensitivity obviously. Properly increasing the width and shortening the length of the open gate area could enhance the sensitivity. However, when the open gate width is too larger or too small, the pH sensitivity would be suppressed conversely. Designing an optimal ratio of the width to the length is important for achieving high sensitivity. This work suggests that the AlInN/GaN-based 2DEG carrier modulated devices would be good candidates for high-performance pH sensors and other related applications.

11.
Dysphagia ; 32(3): 393-400, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28013388

RESUMEN

The purpose of this study was to compare the swallowing function and kinematics in stroke patients with and without tracheostomies. In this retrospective matched case-control study, we compared stroke patients with (TRACH group, n = 24) and without (NO-TRACH group, n = 24) tracheostomies. Patients were matched for age, sex, and stroke-type. Swallowing function was evaluated using the videofluoroscopic dysphagia scale (VDS) and functional oral intake scale (FOIS) obtained from videofluoroscopic swallow study (VFSS) images. Swallowing kinematics were evaluated using a two-dimensional kinematic analysis of the VFSS images. Mean duration of tracheostomy was 132.38 ± 150.46 days in the TRACH group. There was no significant difference in the total VDS score between the TRACH (35.17 ± 15.30) and NO-TRACH groups (29.25 ± 16.66, p = 0.247). FOIS was significantly lower in the TRACH group (2.33 ± 1.40) than in the NO-TRACH group (4.33 ± 1.79, p = 0.001). The TRACH group had a significantly lower maximum vertical displacement (15.23 ± 7.39 mm, p = 0.011) and velocity (54.99 ± 29.59 mm/s, p = 0.011), and two-dimensional velocity (61.07 ± 24.89 mm/s, p = 0.013) of the larynx than the NO-TRACH group (20.18 ± 5.70 mm, 82.23 ± 37.30 mm/s, and 84.40 ± 36.05 mm/s, respectively). Maximum horizontal velocity of the hyoid bone in the TRACH group (36.77 ± 16.97 mm/s) was also significantly lower than that in the NO-TRACH group (47.49 ± 15.73 mm/s, p = 0.032). This study demonstrated that stroke patients with tracheostomies had inferior swallowing function and kinematics than those without tracheostomies. A prospective longitudinal study is needed to elucidate the effect of a tracheostomy on swallowing recovery in stroke patients.


Asunto(s)
Deglución/fisiología , Accidente Cerebrovascular/complicaciones , Traqueostomía/efectos adversos , Fenómenos Biomecánicos/fisiología , Estudios de Casos y Controles , Trastornos de Deglución/etiología , Trastornos de Deglución/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía
12.
Am J Phys Med Rehabil ; 95(5): e67-71, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26829085

RESUMEN

Herpes zoster, commonly known as shingles, is an infectious viral disease characterized by painful, unilateral skin blisters occurring in specific sensory dermatomes. Motor paresis is reported in 0.5% to 5% of patients. Although the mechanism of zoster paresis is still unclear, the virus can spread from the dorsal root ganglia to the anterior horn cell or anterior spinal nerve roots. It rarely involves the brachial plexus. We report a case of brachial plexitis following herpes zoster infection in which pathological lesions were diagnosed using brachial plexus magnetic resonance imaging and treated with ultrasound-guided perineural corticosteroid injection.


Asunto(s)
Neuropatías del Plexo Braquial/tratamiento farmacológico , Neuropatías del Plexo Braquial/virología , Glucocorticoides/uso terapéutico , Herpes Zóster/complicaciones , Triamcinolona/uso terapéutico , Anciano de 80 o más Años , Plexo Braquial/patología , Neuropatías del Plexo Braquial/rehabilitación , Humanos , Inyecciones , Imagen por Resonancia Magnética , Masculino , Dimensión del Dolor , Ultrasonografía Intervencional
13.
Opt Express ; 23(17): 22730-9, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26368241

RESUMEN

We propose, analyze and optimize a two-dimensional conical photonic crystal geometry to enhance light extraction from a high refractive index material, such as an inorganic scintillator. The conical geometry suppresses Fresnel reflections at an optical interface due to adiabatic impedance matching from a gradient index effect. The periodic array of cone structures with a pitch larger than the wavelength of light diffracts light into higher-order modes with different propagating angles, enabling certain photons to overcome total internal reflection (TIR). The numerical simulation shows simultaneous light yield gains relative to a flat surface both below and above the critical angle and how key parameters affect the light extraction efficiency. Our optimized design provides a 46% gain in light yield when the conical photonic crystals are coated on an LSO (cerium-doped lutetium oxyorthosilicate) scintillator.

14.
Support Care Cancer ; 23(8): 2305-10, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25577504

RESUMEN

PURPOSE: This study aims to investigate the comparison of effectiveness between stellate ganglion block (SGB) and complex decongestive physiotherapy (CDT) in breast cancer-related lymphedema (BCRL) patients. METHODS: The study is a retrospective matched cohort study. A total of 60 subjects who had secondary lymphedema after breast cancer treatments were included in this study. Thirty subjects who had SGB were matched with other 30 subjects treated with CDT, which is the standard therapy for BCRL. The groups were matched for age, duration of lymphedema, type of surgery, and history of lymph node dissection. SGB subjects received SGB three times, once every 2 weeks and CDT subjects were treated for 2 weeks. The circumferences of the forearm and upper arm were used as the outcome variable. These parameters were measured with baseline value before each treatment and repeated the evaluation after the treatments. We investigated the difference of circumferences within each treatment and compared the clinical effect between treatments. RESULTS: Sixty subjects (mean age 58.2 ± 8.7) were treated with CDT and SGB each. There was no significant difference in demographic data including cancer treatment. The mean circumferences of the forearm and upper arm after CDT significantly reduced; forearm from 24.91 to 23.87 cm and upper arm from 30.52 to 29.58 cm (p < 0.001). And the clinical effect of SGB was also significant; forearm from 24.90 to 23.64 cm and upper arm from 30.96 to 29.16 cm (p < 0.001). The differences of the forearm between CDT and SGB was not significant, but the circumference of the upper arm was more reduced after SGB treatment (1.81 ± 1.21 cm) than CDT (0.94 cm ± 0.78 cm) (p < 0.01). CONCLUSIONS: SGB is an effective treatment which can reduce the circumference of arm in breast cancer-related lymphedema patients and could be an alternative treatment for lymphedema.


Asunto(s)
Bloqueo Nervioso Autónomo/métodos , Neoplasias de la Mama/terapia , Linfedema/terapia , Modalidades de Fisioterapia , Ganglio Estrellado , Triamcinolona/administración & dosificación , Adulto , Brazo/patología , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/fisiopatología , Estudios de Cohortes , Drenaje , Femenino , Humanos , Escisión del Ganglio Linfático , Linfedema/etiología , Linfedema/fisiopatología , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
15.
Ann Rehabil Med ; 38(2): 174-82, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24855611

RESUMEN

OBJECTIVE: To investigate the accessibility of medical services for Korean people with spinal cord injury (SCI) compared to the control group (CG) and to evaluate significantly related factors. METHODS: A total of 363 community dwelling people with chronic SCI were enrolled and 1,089 age- and sex-matched subjects were randomly selected from the general population as the CG. Self-reported access to medical services was measured by asking "Have you experienced the need for a hospital visit in the last year but could not?". This was followed up by asking the reasons for not receiving services when medically necessary. Variables, including lack of finances, difficulties making medical appointments, and lack of transportation were evaluated for accessibility to medical services. RESULTS: Sixty subjects (16.5%) in the SCI group had difficulties receiving medical services due to a lack of accessibility, compared to 45 (4.1%) in the CG (p<0.001). Variables causing difficulties receiving medical services were lack of transportation (27 persons, 45%), lack of finances (24 persons, 40%), and difficulty scheduling hospital appointments (9 persons, 15%) in the SCI group. In the CG, availability (lack of available time) and acceptability (deciding not to visit the hospital due to mild symptoms) were the reasons for not receiving medical care. CONCLUSION: People with SCI experienced limited accessibility to medical services, which was due to environmental rather than personal factors compared to that in the CG. Therefore, development of social policies to reduce or remove environmental variables is necessary.

16.
Small ; 10(12): 2487-94, 2014 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-24648034

RESUMEN

A multifunctional surface that enables control of wetting, optical reflectivity and mechanical damage of nanostructured interfaces is presented. Our approach is based on imprinting a periodic array of nanosized cones into a UV-curable polyurethane acrylate (PUA), resulting in a self-reinforcing egg-crate topography evenly distributed over large areas up to several cm(2) in size. The resulting surfaces can be either superhydrophilic or superhydrophobic (through subsequent application of an appropriate chemical coating), they minimize optical reflection losses over a broad range of wavelengths and a wide range of angles of incidence, and they also have enhanced mechanical resilience due to greatly improved redistribution of the normal and shearing mechanical loads. The transmissivity and wetting characteristics of the nanoscale egg-crate structure, as well as its resistance to mechanical deformation are analyzed theoretically. Experiments show that the optical performance together with self-cleaning or anti-fogging behavior of the inverted nanocone topography is comparable to earlier designs that have used periodic arrays of nanocones to control reflection and wetting. However the egg-crate structures are far superior in terms of mechanical robustness, and the ability to replicate this topography through several generations is promising for large-scale commercial applications where multifunctionality is important.

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