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1.
J Clin Med ; 13(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38592022

RESUMO

Background: This study evaluated the effectiveness of short fully covered self-expanding metal stents (FCSEMS) with an anti-migration design in treating benign biliary strictures (BBS) not related to living donor liver transplantation (LDLT). Methods: A retrospective analysis was conducted on 75 patients who underwent FCSEMS insertion for BBS management. Stents were initially kept for 3 months and exchanged every 3 months until stricture resolution. Adverse events and stricture recurrence after FCSEMS removal were assessed during follow-up. Results: The study outcomes were technical success, stenosis resolution, and treatment failure. Technical success was 100%, with stricture resolution in 99% of patients. The mean onset time of BBS post-surgery was 4.4 years, with an average stent indwelling period of 5.5 months. Stricture recurrence occurred in 20% of patients, mostly approximately 18.8 months after stent removal. Early cholangitis and stent migration were noted in 3% and 4% of patients, respectively. Conclusions: This study concludes that short FCSEMS demonstrate high efficacy in the treatment of non-LDLT-related BBS, with a low incidence of interventions and complications. Although this is a single-center, retrospective study with a limited sample size, the findings provide preliminary evidence supporting the use of short FCSEMS as a primary treatment modality for BBS. To substantiate these findings, further research involving multicenter studies is recommended to provide additional validation and a broader perspective.

2.
ACS Omega ; 8(6): 5885-5892, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816670

RESUMO

A new graphene quantum dot (GQD) fabrication method is presented, which employs a lithographic approach based on self-assembled Au nanoparticles formed by solid-state dewetting. The GQDs are formed by the patterned etching of a graphene layer enabled by Au nanoparticles, and their size is controllable through that of the Au nanoparticles. GQDs are fabricated with four different diameters: 12, 14, 16, and 27 nm. The geometrical features and lattice structures of the GQDs are determined using transmission electron microscopy (TEM). Hexagonal lattice fringes in the TEM image and G- and 2D-band Raman scattering evidence the graphitic characteristics of the GQDs. The oxygen content can be controlled by thermal reduction under a hydrogen atmosphere. In GQDs, the absorption peak wavelengths in the ultraviolet range tend to decrease as the size of the GQDs decreases. They also exhibit apparent photoluminescence (PL). The PL peak wavelength is approximately 600 nm and becomes shorter as the size of the GQDs decreases. The blue shift in the optical absorption and PL of the smaller GQDs is attributed to the quantum confinement effect. The proposed GQD fabrication method can provide a way to control the physical and chemical properties of GQDs via their size and oxygen content.

3.
Sensors (Basel) ; 23(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36679827

RESUMO

We present a 640 × 480 CMOS image sensor (CIS) with in-circuit bi-directional gamma correction with a proposed digital-correlated double sampling (CDS) structure. To operate the gamma correction in the CIS, the transfer function of the analog-to-digital converter can be changed by controlling the clock frequency of the counter using analog CDS. However, the analog CDS is vulnerable to capacitor mismatch, clock feedthrough, etc. Therefore, we propose a digital-CDS method with a hold-and-go counter structure to operate the bi-directional gamma correction in the CIS. The proposed CIS achieves a 10-bit resolution using a global log-exponential counter and configurable column reset counter with a resolution of 8/9 bits. The sensor was fabricated in a 0.11 µm CIS process, and the full chip area was 5.9 mm × 5.24 mm. The measurement results showed a maximum SNR improvement of 10.41% with the proposed bi-directional gamma-corrected digital-CDS with the hold-and-go counter. The total power consumption was 6.3 mW at a rate of 16.6 frames per second with analog, pixel, and digital supply voltages of 3.3 V, 3.3 V, and 1.5 V, respectively.


Assuntos
Imagem Óptica
4.
Pain Physician ; 25(7): E1105-E1113, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36288597

RESUMO

BACKGROUND: Handgrip strength (HGS) and psoas muscle index (PMI) are widely used protocols for screening or diagnosing sarcopenia by measuring muscle strength and mass. Epidural steroid injection (ESI) is a common intervention for the treatment of spinal pain; however, the influence of pre-procedural sarcopenic status on therapeutic effects after ESI has not been investigated. OBJECTIVES: In the present study, whether pre-procedural HGS or PMI predicts analgesic efficacy of ESI in elderly patients with degenerative lumbar spinal disease was investigated. STUDY DESIGN: This was a retrospective observational study. SETTING: The study included patients from the outpatient department for interventional pain management at a university hospital. METHODS: Following institutional review board (IRB) approval, patients >= 65 years of age who underwent fluoroscopy-guided lumbar ESI from 2016 to 2017 in our clinic were enrolled in the present study. Good analgesia was defined as >= 50% reduction in pain score at 4 weeks after injection. Patient characteristics, pain-related factors, clinical factors, HGS, and PMI measurements were collected and analyzed using multivariate analysis to identify the predictors of good analgesia after lumbar ESI. In addition, a receiver operating characteristic curve (ROC) analysis was performed, and area under the curve (AUC) values with 95% confidence interval (CI) were calculated for the HGS. RESULTS: A total of 259 patients satisfied the study protocol requirements. HGS was significantly higher in the good analgesia group (23.12 ± 7.54 vs 16.55 ± 6.66 kg, P < 0.001). However, the PMI did not differ between the 2 groups (5.25 ± 1.55 vs 5.08 ± 1.69 cm2/m2, P = 0.406). Multivariate analysis revealed higher HGS (odds ratio, OR = 1.142, 95% CI = 1.094-1.193, P < 0.001) and low-grade foraminal stenosis (OR = 0.403, 95% CI = 0.199-0.814, P = 0.011) were significantly associated with good analgesia after injection. The AUC values with 95% CI for HGS were 0.819 (0.718-0.920) in men and 0.800 (0.732-0.869) in women. In addition, HGS cutoff values for predicting good analgesic outcomes were 26.5 kg in men and 16.5 kg in women. LIMITATIONS: This study was conducted in a single center, and sample size was relatively small. The lack of physical performance evaluation did not fully meet the current criteria for sarcopenia. In addition, post-procedural clinical data associated with disability or quality of life could not be collected. CONCLUSION: In the present study, pre-procedural HGS was an independent predictor of analgesic efficacy after ESI in elderly patients with degenerative lumbar spinal disease. However, the PMI was not associated with pain relief after injection.


Assuntos
Sarcopenia , Doenças da Coluna Vertebral , Estenose Espinal , Masculino , Humanos , Feminino , Idoso , Estenose Espinal/diagnóstico , Injeções Epidurais/métodos , Músculos Psoas , Força da Mão , Sarcopenia/complicações , Sarcopenia/tratamento farmacológico , Dor/tratamento farmacológico , Doenças da Coluna Vertebral/tratamento farmacológico , Esteroides , Analgésicos/uso terapêutico
5.
Cancers (Basel) ; 14(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36077766

RESUMO

BACKGROUND AND AIM: This study investigated the administration of combination therapy, allogeneic natural killer (NK) cells and pembrolizumab in the treatment of advanced biliary tract cancer to determine the safety and tolerability (phase 1) and the efficacy and safety (phase 2a). METHODS: Forty patients (phase 1, n = 6; phase 2a, n = 34) were enrolled between December 2019 and June 2021. The patients received highly activated allogeneic NK cells ("SMT-NK") on weeks 1 and 2 and pembrolizumab on week 1. This 3-week schedule (one cycle) was repeated until confirmed disease progression, intolerable adverse events (AEs), patient withdrawal, or finishing the maximum treatment schedule. The tumor response was evaluated after every three cycles. RESULTS: In phase 1, four patients (66.7%) experienced seven AEs, but no severe AE was observed. In phase 2a, 126 AEs occurred in 29 patients (85.3%). Severe AEs (≥grade 3) were reported in 16 patients (47.1%). The overall response rate (ORR) was 17.4% in the full analysis set and 50.0% in the per-protocol set. CONCLUSIONS: SMT-NKs plus pembrolizumab resulted in no severe AEs directly related to the drug combination. The combination therapy also exerted antitumor activity with improved efficacy compared to the recent monotherapy with pembrolizumab in patients with advanced biliary tract cancer.

6.
Cancers (Basel) ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35159120

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer for which no early diagnostic method is available. The immune surveillance hypothesis suggests that the immune system plays crucial roles in tumor development and progression. We validated a PDAC-specific biomarker derived from peripheral blood mononuclear cells (PBMCs) to facilitate early PDAC diagnosis. mRNA levels of interleukin-7R (IL-7R), reportedly a potential immunological marker for PDAC, were measured in PBMCs isolated prospectively from healthy controls (n = 100) and patients with PDAC (n = 135), pancreatic cysts (n = 82), chronic pancreatitis (n = 42), acute pancreatitis (n = 47), and other malignancies (n = 116). The IL-7R level was significantly higher in patients with PDAC than in healthy controls, patients with benign pancreatic disease, and patients with other malignancies. As diagnostic parameters, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for IL-7R were 58.5%, 92%, 90.8%, 62.2%, and 72.8%, respectively. The area under the receiver operating characteristic curve (AUROC) was 0.766. IL-7R levels did not differ between resectable and unresectable PDAC cases. The combined measurement of IL-7R and carbohydrate antigen 19-9 (CA19-9) significantly improved the diagnostic parameters and AUROC compared with the use of IL-7R or CA19-9 alone. IL-7R is significantly upregulated in PBMCs in patients with PDAC, and it may be a novel diagnostic marker for PDAC. The combined use of IL-7R and CA19-9 enhanced the diagnostic performance.

7.
J Clin Anesth ; 77: 110646, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35021139

RESUMO

STUDY OBJECTIVE: To investigate the mechanism of action of the thoracic intertransverse process (ITP) block. DESIGN: Three-dimensional micro-computed tomography (3D micro-CT) study and cadaveric evaluation. SETTING: A translational research unit for anatomy and analgesia in a university hospital. PATIENTS: Twelve embalmed and three non-embalmed human cadavers were used in this study. MEASUREMENTS: Micro-CT images of the mid-thoracic paravertebral space and its adjacent ligamentous tissues were acquired and 3D images were reconstructed. Manual dissection and histologic examination of these structures complemented the images. To confirm our findings, the dye-spreading pattern after ultrasound-guided ITP injection of 20 mL dye solution at T4-T5 was evaluated. MAIN RESULTS: Micro-CT and histologic findings showed that the costotransverse foramen (the medial slit of the superior costotransverse ligament) and the costotransverse space (between the rib and the transverse process) were potential pathways to the thoracic paravertebral space during ITP block. Single-level ITP injection with a dye solution resulted in a multilevel segmental paravertebral spread in cadaveric evaluation. CONCLUSIONS: The space posterior to the superior costotransverse ligament, the target area for ITP blocks, has potential anatomical pathways to the thoracic paravertebral space. The costotransverse foramen and the costotransverse space provided the anatomical conduit for the anterior and intersegmental paravertebral spread of the ITP block.


Assuntos
Bloqueio Nervoso , Humanos , Cadáver , Bloqueio Nervoso/métodos , Vértebras Torácicas/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Microtomografia por Raio-X
8.
Cancers (Basel) ; 13(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34572940

RESUMO

Neuroendocrine neoplasms (NENs) of the gallbladder (GB) are extremely rare. We aimed to compare the clinical features, disease progression, management, and prognosis of patients with GB-NENs with those of patients with GB-adenocarcinomas (ADCs). A total of 21 patients with GB-NENs and 206 patients with GB-ADCs, treated at three tertiary medical centers between January 2010 and December 2020, were enrolled. Of the 21 patients with GB-NENs, 20 were diagnosed with poorly differentiated small-cell neuroendocrine carcinomas (NECs), and 1 patient had large-cell NEC. All patients presented with advanced stages of cancer with extensive local extension and/or distant metastasis and non-specific symptoms. Tumor-node-metastasis stage IIIB and IV (A/B) tumors were found in 6 and 15 (1/14) patients, respectively. Nine patients with GB-NEC who underwent surgical resection had a significantly better progression-free survival (PFS) than those who did not undergo surgery. After a propensity score matching with a 1:1 ratio using the American Joint Committee on Cancer stage, age, sex, and operation status, 19 pairs of patients were included. Compared with stage-matched patients with GB-ADC, patients with GB-NEC had similar overall survival and PFS. However, as GB-NEC is rarely diagnosed early, further studies investigating methods for the early diagnosis and improvement in the survival of patients with GB-NEC are needed.

9.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799632

RESUMO

High orthodontic forces and various directions of applied forces can be associated with loosening of the screw anchorage in the bone. Screw designs have been modified to increase the stability of the miniscrews. This research evaluates the influence of three-designs on the stability of orthodontic miniscrews. A conventionally cylinder-type miniscrew design (Bio-Action screw, Jin-Biomed co., Bucheon, Korea) was set as a control, and three conditions were studied based on modifications of this control design. Condition-1 has narrowed threads in the upper part of the screw; Condition-2 has a notch at the middle part; and Condition-3 has the combination of Condition-1 and Condition-2. The moment required to unwind the miniscrew to five degrees is tested, and the moment generated at the cortical bone and the trabecular bone were calculated with finite element analysis. Compared to the control, all three conditions showed a higher moment required to unwind the miniscrew and a higher moment generated at the cortical bone. At the trabecular bone, condition-2 and -3 showed higher moment than the control, and condition-1 showed similar moment to the control. Condition-3 required a higher overall moment to unwind the miniscrew. These findings validate the design modifications used to increase the rotational resistance.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Análise de Elementos Finitos , República da Coreia , Titânio
10.
Am J Health Behav ; 45(1): 111-124, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33402242

RESUMO

Objectives: In this study, we aimed to find the influential factors in determining individuals' use and non-use of fitness and diet apps on smartphones. To this end, we focused on diverse groups of predictors that would significantly affect people's use and non-use of these apps. Methods: Overall, we considered 105 factors as potential predictors and included them in further analyses using a machine learning algorithm, XGBoost. The main reason for selecting this particular algorithm was that it had been known as one of the most accurate and popular algorithms for predicting consumer behaviors. Results: We found the accuracy score of those factors for predicting people's use and non-use of fitness and diet apps was approximately 71.3%. In particular, the most influential predictors were mainly related to social influence, media use, overeating, social support, health management, and attitudes toward exercise. Conclusion: These findings contribute to helping scholars and practitioners to develop more practical strategies of the implementation of fitness and diet apps.


Assuntos
Exercício Físico , Aplicativos Móveis , Smartphone , Dieta , Humanos , Aprendizado de Máquina
11.
Korean J Fam Med ; 42(3): 250-254, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32438536

RESUMO

Pancytopenia represents a unique challenge for primary care doctors and its etiological causes encompass various specialties, including hematology and rheumatology. Despite the existence of effective tests such as bone marrow biopsy and immunoassays to rule out the potential causes of pancytopenia, it is often difficult to pinpoint the exact diagnosis. In this case report, we have described such a 'gray zone' patient, who presented with pancytopenia, neutropenia, and splenomegaly, and was being treated for fungal pneumonia before being transferred to Severance Hospital (department of family medicine). As the patient had a 10-year history of multiple, long-term hospital admissions that were having a severely debilitating impact on the quality of life, we performed a partial splenic embolization as a potential cure for the symptoms. Although this induced acute blood count recovery, it failed to prevent eventual mortality from septic shock.

12.
Sci Rep ; 10(1): 22059, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33328514

RESUMO

A dual-functional ultraviolet (UV) photodetector with a large UV-to-visible rejection ratio is presented, in which interdigitated finger-type two-dimensional graphene electrodes are introduced to an AlGaN/GaN heterostructure. Two photocurrent generation mechanisms of photovoltaic and photoconductive dominances coexist in the device. The dominance of the mechanisms changes with the induced bias voltage. Below a threshold voltage, the device showed fairly low responsivities but fast response times, as well as a constant photocurrent against the induced bias. However, the opposite characteristics appeared with high bias voltage. Specifically, above the threshold voltage, the device showed high responsivities with additional gain, but slow rise and recovery times. For instance, the responsivity of 10.9 A/W was observed with the gain of 760 at the induced bias voltage of 5 V. This unique multifunctionality enabled by the combination of an AlGaN/GaN heterostructure with graphene electrodes facilitates the development of a single device that can achieve multiple purposes of photodetection.

13.
Am J Orthod Dentofacial Orthop ; 158(4): 587-598, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32839074

RESUMO

A boy aged 8 years 11-months with 4 missing teeth in his mandibular arch and with a skeletal Class II pattern was treated with autotransplantation of developing premolars from his maxillary arch with the aid of temporary skeletal anchorage devices. The active treatment duration was 25 months. After treatment, he had a normal occlusion, and his profile was improved. Posttreatment records at 12 months showed stable occlusion and successfully autotransplanted premolars.


Assuntos
Anodontia , Perda de Dente , Autoenxertos , Dente Pré-Molar , Criança , Humanos , Masculino , Transplante Autólogo
14.
Psychiatry Investig ; 17(7): 681-687, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32631033

RESUMO

OBJECTIVE: Despite the growing need for psychological programs for North Korean refugees, most psychological interventions for these people lack a verification study that tests their effectiveness. This study aims to evaluate the effectiveness of cognitive behavioral therapy (CBT) in North Korean refugees. METHODS: Participants included 38 North Korean refugees, of whom 23 participated in simple relaxation and 15 participated in CBT. The Korean version of the Center for Epidemiologic Studies Depression Scale (CES-D), State-Trait Anxiety Inventory-State (STAI-S), and Impact of Event Scale-Revised were used to evaluate symptoms pre- and post-intervention. RESULTS: Participants had a significant decrease in CES-D scores after treatment (p=0.037). The decrease in CES-D was larger in those who participated in the CBT compared to those in simple relaxation (p=0.023). The superior effects that CBT had on depressive symptoms over simple relaxation were particularly more prominent in those with severe depression (p=0.035). Participants with high levels of anxiety also showed significant decreases in STAI-S scores after treatment, regardless of which type of program they participated in (p=0.023). CONCLUSION: This preliminary findings suggests that CBT is an effective psychiatric approach in treating depressive symptoms in North Korean refugees, especially for those with a higher degree of depressive symptom.

15.
Nanotechnology ; 31(4): 045304, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31593938

RESUMO

Polarized ultraviolet (UV) emitters are essential for various applications, such as photoalignment devices for liquid crystals, high-resolution imaging devices, highly sensitive sensors, and steppers. To increase the high polarization ratio (PR) of a UV emitter, the grating period should be decreased than that of the visible emitter. However, the fabrication of the short period grating directly on UV emitters is still limited. In this study, we demonstrate that 200, 100, and 50 nm period aluminum (Al)-based wire-grid polarizers (WGPs) can be fabricated directly on UV emitters by a solvent-assisted nanotransfer process. The UV emitter with a grating period of 100 nm shows a PR of 84%, and an electroluminescence efficiency that is 22.5% and 48% higher than those of UV emitters with 50 nm and 200 nm period WGPs, respectively, due to the increased photon extraction efficiency (PEE). The higher PEE is attributed to the optical cavity property of the Al metal reflector with low light loss and the surface plasmon effect of the Al grating layer.

16.
Disabil Health J ; 13(2): 100878, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31859232

RESUMO

BACKGROUND: There has been a continuous increase of smart device use among people with physical disabilities in Korea. In spite of previous research on those people's motives to adopt smart devices, little investigation has been conducted to scrutinize post-adoption behaviors of using smart devices among people with physical disabilities. OBJECTIVE: /Hypothesis: Based on the post-adoption model, this study examined the relationship between post-adoption beliefs regarding smart devices and behavioral intentions toward continued use of smartphones among people with physical disabilities. Moreover, this study investigated the moderating effects of self-efficacy on the relationships among the main study variables. METHODS: Both online and paper-pencil surveys were conducted, resulting in a total of 108 questionnaires collected from people with physical disabilities. RESULTS: A path analysis showed that, with the exception of perceived ease of use, all variables (confirmation, perceived usefulness, and satisfaction of smart device use) had significant effects on continuance intention to use smart devices. Another main finding of this study was the significant moderating effects of general self-efficacy on the relationships among the three variables of confirmation, perceived usefulness, and continuance intention of smart devices. The relationships among the three variables were significantly stronger among people with lower levels of general self-efficacy. CONCLUSIONS: This study's main findings will aid the thorough comprehension of the mechanisms that lead people with physical disabilities to continue to use smart devices.


Assuntos
Atitude Frente aos Computadores , Comportamento do Consumidor/estatística & dados numéricos , Pessoas com Deficiência/psicologia , Pessoas com Deficiência/estatística & dados numéricos , Smartphone/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Inquéritos e Questionários
17.
Am J Transplant ; 20(5): 1439-1446, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31874120

RESUMO

Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disorder (EBV-PTLD) is a serious complication in lung transplant recipients (LTRs) associated with significant mortality. We performed a single-center retrospective study to evaluate the risks for PTLD in LTRs over a 7-year period. Of 611 evaluable LTRs, we identified 28 cases of PTLD, with an incidence of 4.6%. Kaplan-Meier analysis showed a decreased freedom from PTLD in idiopathic pulmonary fibrosis (IPF)-LTRs (P < .02). Using a multivariable Cox proportional hazards model, we found IPF (hazard ratio [HR] 3.51, 95% confidence interval [CI] 1.33-8.21, P = .01) and alemtuzumab induction therapy (HR 2.73, 95% CI 1.10-6.74, P = .03) as risk factors for PTLD, compared to EBV mismatch (HR: 34.43, 95% CI 15.57-76.09, P < .0001). Early PTLD (first year) was associated with alemtuzumab use (P = .04), whereas IPF was a predictor for late PTLD (after first year) (P = .002), after controlling for age and sex. Kaplan-Meier analysis revealed a shorter time to death from PTLD in IPF LTRs compared to other patients (P = .04). The use of alemtuzumab in EBV mismatch was found to particularly increase PTLD risk. Together, our findings identify IPF LTRs as a susceptible population for PTLD. Further studies are required to understand the mechanisms driving PTLD in IPF LTRs and develop strategies to mitigate risk.


Assuntos
Infecções por Vírus Epstein-Barr , Fibrose Pulmonar Idiopática , Transtornos Linfoproliferativos , Infecções por Vírus Epstein-Barr/etiologia , Herpesvirus Humano 4 , Humanos , Fibrose Pulmonar Idiopática/etiologia , Pulmão , Transtornos Linfoproliferativos/etiologia , Estudos Retrospectivos , Fatores de Risco , Transplantados
18.
Nanoscale ; 11(39): 18444-18448, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31576892

RESUMO

We presented a new functional GaInN-based light-emitting diode (LED) that is capable of protecting itself from unwanted thermal damage (a so-called self-protective LED). This functionality was achieved by incorporating VO2 nanowires on the LED chip. VO2 nanowires, as metal-insulator transition materials, show a phase transition from insulating to metallic at a characteristic transition temperature. By placing a VO2 nanowire between the n- and p-contacts of an LED, a parallel circuit was formed with the existing diode. As the VO2 nanowire became metal-like at its characteristic temperature, it induced a short-circuit state in the device, protecting the LED from heat damage at elevated temperatures. Details on the self-protective LED were elucidated, from a conceptual description to experimental proof.

19.
Health Commun ; 34(9): 1043-1052, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-29652521

RESUMO

This study examined the relationships across social media use, social support, depression, and general psychological disposition among people with movement or mobility disabilities in Korea. First, with survey data (n = 91) collected from users of social network sites (SNSs) and online communities, hypotheses regarding positive associations between intensity of an individual's engagement in social media and four different types of social support-emotional, instrumental, informational, and appraisal support-were tested as well as hypotheses regarding mediation effects of the social support variables in the association between social media use and depression. Second, through focus group interviews (n = 15), influences of social media use on social support were more thoroughly explored as well as their influences on general psychological disposition. Results from hierarchical regression analyses confirmed that both intensity of SNS use and online community use significantly predicted instrumental, informational, and appraisal support, while they did not predict emotional support. Further regression and Sobel tests showed that higher levels of intensity of SNS use and of online community use both led to lower levels of depression through the mediation of instrumental and informational support. Analysis of the interviews further revealed the positive roles of social media use in building social support and healthy psychological dispositions. However, analysis also revealed some negative consequences of and limitations to social media use for those with physical disabilities. These findings expand our knowledge of the context and implications of engaging in online social activities for people with physical disabilities.


Assuntos
Depressão/epidemiologia , Pessoas com Deficiência/psicologia , Ajustamento Emocional , Mídias Sociais , Apoio Social , Adulto , Feminino , Grupos Focais , Humanos , Masculino , República da Coreia/epidemiologia , Inquéritos e Questionários
20.
Health Commun ; 32(12): 1445-1453, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27356103

RESUMO

This study explored how the gratifications obtained from the use of diet and fitness apps may motivate users to continue their use of these apps. The effects of seven gratifications obtained were analyzed through hierarchical regression analyses. Results showed that the five gratifications of recordability, networkability, credibility, comprehensibility, and trendiness significantly predicted user intention to continue using diet/fitness apps; the hypothesized gratifications of accuracy and entertainment were not significant predictors. These findings contribute to broadening our theoretical and practical knowledge of new digital, mobile media phenomena by identifying use motivations specific to diet/fitness apps. Based on the findings, recommendations for researchers, practitioners, and developers are provided.


Assuntos
Dieta/psicologia , Comportamentos Relacionados com a Saúde , Aplicativos Móveis/tendências , Motivação , Aptidão Física/psicologia , Coleta de Dados , Feminino , Humanos , Internet , Masculino , Aplicativos Móveis/estatística & dados numéricos , Comportamento Social , Inquéritos e Questionários , Adulto Jovem
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