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1.
Nano Lett ; 24(30): 9163-9168, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39037721

RESUMO

Magneto-optical (MO) polymer nanocomposites have emerged as alternatives to conventional MO crystals, particularly in nanophotonics applications, thanks to their better processing flexibility and superior Verdet constants. However, a higher Verdet constant commonly comes with excessive optical loss due to increased absorption and scattering, resulting in a constant or reduced figure-of-merit (FOM) defined as the Verdet constant over optical loss. By doping magnetite (Fe3O4) nanoparticles with Tb3+ ions, we report a new strategy to enhance the Verdet constant without increasing the optical loss. The Fe3O4:Tb3+ nanocomposite is one of a kind that simultaneously achieves a state-of-the-art Verdet constant of 5.6 × 105 °/T·m and a state-of-the-art FOM of 31°/T in the near-infrared region.

3.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691741

RESUMO

Broadband frequency comb generation through cascaded quadratic nonlinearity remains experimentally untapped in free-space cavities with bulk χ(2) materials mainly due to the high threshold power and restricted ability of dispersion engineering. Thin-film lithium niobate (LN) is a good platform for nonlinear optics due to the tight mode confinement in a nano-dimensional waveguide, the ease of dispersion engineering, large quadratic nonlinearities, and flexible phase matching via periodic poling. Here we demonstrate broadband frequency comb generation through dispersion engineering in a thin-film LN microresonator. Bandwidths of 150 nm (80 nm) and 25 nm (12 nm) for center wavelengths at 1560 and 780 nm are achieved, respectively, in a cavity-enhanced second-harmonic generation (doubly resonant optical parametric oscillator). Our demonstration paves the way for pure quadratic soliton generation, which is a great complement to dissipative Kerr soliton frequency combs for extended interesting nonlinear applications.

4.
Ther Adv Musculoskelet Dis ; 16: 1759720X241237872, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665415

RESUMO

Background: Despite being the gold standard for diagnosing osteoporosis, dual-energy X-ray absorptiometry (DXA) is an underutilized screening tool for osteoporosis. Objectives: This study proposed and validated a controllable feature layer of a convolutional neural network (CNN) model with a preprocessing image algorithm to classify osteoporosis and predict T-score on the proximal hip region via simple hip radiographs. Design: This was a single-center, retrospective study. Methods: An image dataset of 3460 unilateral hip images from 1730 patients (age ⩾50 years) was retrospectively collected with matched DXA assessment for T-score for the targeted proximal hip regions to train (2473 unilateral hip images from 1430 patients) and test (497 unilateral hip images from 300 patients) the proposed CNN model. All images were processed with a fully automated CNN model, X1AI-Osteo. Results: The proposed screening tool illustrated a better performance (sensitivity: 97.2%; specificity: 95.6%; positive predictive value: 95.7%; negative predictive value: 97.1%; area under the curve: 0.96) than the open-sourced CNN models in predicting osteoporosis. Moreover, when combining variables, including age, body mass index, and sex as features in the training metric, there was high consistency in the T-score on the targeted hip regions between the proposed CNN model and the DXA (r = 0.996, p < 0.001). Conclusion: The proposed CNN model may identify osteoporosis and predict T-scores on the targeted hip regions from simple hip radiographs with high accuracy, highlighting the future application for population-based opportunistic osteoporosis screening with low cost and high adaptability for a broader population at risk. Trial registration: TMU-JIRB N201909036.

5.
J Orthop Surg Res ; 19(1): 270, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689328

RESUMO

BACKGROUND: Rotator cuff tears (RCTs) are a common musculoskeletal disorder, and arthroscopic rotator cuff repair (ARCR) is widely performed for tendon repair. Handgrip strength correlates with rotator cuff function; however, whether preoperative grip strength can predict functional outcomes in patients undergoing ARCR remains unknown. This study aimed to investigate the correlation between preoperative grip strength and postoperative shoulder function following ARCR. METHODS: A total of 52 patients with full-thickness repairable RCTs were prospectively enrolled. Baseline parameters, namely patient characteristics and intraoperative findings, were included for analysis. Postoperative shoulder functional outcomes were assessed using the Quick Disabilities of the Arm, Shoulder, and Hand (QDASH) questionnaire and Constant-Murley scores (CMSs). Patients were followed up and evaluated at three and six months after ARCR. The effects of baseline parameters on postoperative outcomes were measured using generalized estimating equations. RESULTS: At three and six months postoperatively, all clinical outcomes evaluated exhibited significant improvement from baseline following ARCR. Within 6 months postoperatively, higher preoperative grip strength was significantly correlated with higher CMSs (ß = 0.470, p = 0.022), whereas increased numbers of total suture anchors were significantly correlated with decreased CMSs (ß = - 4.361, p = 0.03). Higher body mass index was significantly correlated with higher postoperative QDASH scores (ß = 1.561, p = 0.03) during follow-up. CONCLUSIONS: Higher baseline grip strength predicts more favorable postoperative shoulder function following ARCR. A preoperative grip strength test in orthopedic clinics may serve as a predictor for postoperative shoulder functional recovery in patients undergoing ARCR.


Assuntos
Artroscopia , Força da Mão , Lesões do Manguito Rotador , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Artroscopia/métodos , Força da Mão/fisiologia , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/fisiopatologia , Idoso , Estudos Prospectivos , Período Pré-Operatório , Período Pós-Operatório , Resultado do Tratamento , Valor Preditivo dos Testes , Recuperação de Função Fisiológica/fisiologia , Manguito Rotador/cirurgia , Manguito Rotador/fisiopatologia , Seguimentos , Adulto , Ombro/cirurgia , Ombro/fisiopatologia
6.
Biomedicines ; 12(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540268

RESUMO

BACKGROUND: The perioperative outcomes of a partial hepatectomy for hepatocellular carcinoma (HCC) have improved. However, high recurrence rates after a curative hepatectomy for HCC is still an issue. This study aimed to analyze the difference between various recurrence patterns. METHODS: We retrospectively reviewed 754 patients with HCC who underwent a curative hepatectomy between January 2012 and March 2021. Patients with recurrent events were categorized into three types: regional recurrence (type I), multiple intrahepatic recurrence (type II), or presence of any distant metastasis (type III). RESULTS: The median follow-up period was 51.2 months. Regarding recurrence, 375 (49.7%) patients developed recurrence, with 244 (32.4%), 51 (6.8%), and 80 (10.6%) patients having type I, II, and III recurrence, respectively. Type III recurrence appeared to be more common in male patients and those with major liver resection, vascular invasion, a large tumor size (>5 cm), a higher tumor grade, and higher levels of AST and AFP (p < 0.05). Patients who had distant metastasis at recurrence had the shortest recurrence time and the worst overall survival (p < 0.001 and p < 0.001). CONCLUSIONS: our study demonstrated that recurrence with distant metastasis occurred earliest and had the worst outcome compared to regional or multiple intrahepatic recurrences.

7.
BMC Gastroenterol ; 24(1): 99, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443794

RESUMO

In this study, we implemented a combination of data augmentation and artificial intelligence (AI) model-Convolutional Neural Network (CNN)-to help physicians classify colonic polyps into traditional adenoma (TA), sessile serrated adenoma (SSA), and hyperplastic polyp (HP). We collected ordinary endoscopy images under both white and NBI lights. Under white light, we collected 257 images of HP, 423 images of SSA, and 60 images of TA. Under NBI light, were collected 238 images of HP, 284 images of SSA, and 71 images of TA. We implemented the CNN-based artificial intelligence model, Inception V4, to build a classification model for the types of colon polyps. Our final AI classification model with data augmentation process is constructed only with white light images. Our classification prediction accuracy of colon polyp type is 94%, and the discriminability of the model (area under the curve) was 98%. Thus, we can conclude that our model can help physicians distinguish between TA, SSA, and HPs and correctly identify precancerous lesions such as TA and SSA.


Assuntos
Adenoma , Pólipos , Humanos , Inteligência Artificial , Endoscopia , Redes Neurais de Computação , Adenoma/diagnóstico por imagem
8.
JMIR Public Health Surveill ; 10: e46591, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38342504

RESUMO

BACKGROUND: To enhance postoperative patient survival, particularly in older adults, understanding the predictors of mortality following hip fracture becomes paramount. Air pollution, a prominent global environmental issue, has been linked to heightened morbidity and mortality across a spectrum of diseases. Nevertheless, the precise impact of air pollution on hip fracture outcomes remains elusive. OBJECTIVE: This retrospective study aims to comprehensively investigate the profound influence of a decade-long exposure to 12 diverse air pollutants on the risk of post-hip fracture mortality among older Taiwanese patients (older than 60 years). We hypothesized that enduring long-term exposure to air pollution would significantly elevate the 1-year mortality rate following hip fracture surgery. METHODS: From Taiwan's National Health Insurance Research Database, we obtained the data of patients who underwent hip fracture surgery between July 1, 2003, and December 31, 2013. Using patients' insurance registration data, we estimated their cumulative exposure levels to sulfur dioxide (SO2), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), particulate matter having a size of <10 µm (PM10), particulate matter having a size of <2.5 µm (PM2.5), nitrogen oxides (NOX), nitrogen monoxide (NO), nitrogen dioxide (NO2), total hydrocarbons (THC), nonmethane hydrocarbons (NMHC), and methane (CH4). We quantified the dose-response relationship between these air pollutants and the risk of mortality by calculating hazard ratios associated with a 1 SD increase in exposure levels over a decade. RESULTS: Long-term exposure to SO2, CO, PM10, PM2.5, NOX, NO, NO2, THC, NMHC, and CH4 demonstrated significant associations with heightened all-cause mortality risk within 1 year post hip fracture surgery among older adults. For older adults, each 1 SD increment in the average exposure levels of SO2, CO, PM10, PM2.5, NOX, NO, NO2, THC, NMHC, and CH4 corresponded to a substantial escalation in mortality risk, with increments of 14%, 49%, 18%, 12%, 41%, 33%, 38%, 20%, 9%, and 26%, respectively. We further noted a 35% reduction in the hazard ratio for O3 exposure suggesting a potential protective effect, along with a trend of potentially protective effects of CO2. CONCLUSIONS: This comprehensive nationwide retrospective study, grounded in a population-based approach, demonstrated that long-term exposure to specific air pollutants significantly increased the risk of all-cause mortality within 1 year after hip fracture surgery in older Taiwanese adults. A reduction in the levels of SO2, CO, PM10, PM2.5, NOX, NO, NO2, THC, NMHC, and CH4 may reduce the risk of mortality after hip fracture surgery. This study provides robust evidence and highlights the substantial impact of air pollution on the outcomes of hip fractures.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Fraturas do Quadril , Humanos , Idoso , Estudos de Coortes , Dióxido de Nitrogênio/análise , Estudos Retrospectivos , Taiwan/epidemiologia , Dióxido de Carbono , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Fraturas do Quadril/cirurgia , Fraturas do Quadril/induzido quimicamente , Óxido Nítrico , Hidrocarbonetos
9.
Nat Commun ; 15(1): 55, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168081

RESUMO

Dissipative Kerr soliton (DKS) microcomb has emerged as an enabling technology that revolutionizes a wide range of applications in both basic science and technological innovation. Reliable turnkey operation with sub-optical-cycle and sub-femtosecond timing jitter is key to the success of many intriguing microcomb applications at the intersection of ultrafast optics and microwave electronics. Here we propose an approach and demonstrate the first turnkey Brillouin-DKS frequency comb to the best of our knowledge. Our microresonator-filtered laser design offers essential benefits, including phase insensitivity, self-healing capability, deterministic selection of the DKS state, and access to the ultralow noise comb state. The demonstrated turnkey Brillouin-DKS frequency comb achieves a fundamental comb linewidth of 100 mHz and DKS timing jitter of 1 femtosecond for averaging times up to 56 µs. The approach is universal and generalizable to various device platforms for user-friendly and field-deployable comb devices.

10.
World J Cardiol ; 15(12): 649-654, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38173905

RESUMO

BACKGROUND: Isolated single coronary artery is a rare congenital anomaly. R-I subtype single coronary artery is even rarer. In this subtype, a very large right coronary artery extends in the coronary sulcus to the anterior base of the heart where it produces the left anterior descending coronary artery. Currently, only a few case reports are available in the literature for this anomaly. CASE SUMMARY: Here, we report the case of a 62-year-old woman who presented to the cardiology clinic with decreased exercise tolerance and poor blood pressure control. The patient underwent coronary angiography (CAG) and emission computed tomography (ECT). CAG images revealed a single gigantic right coronary artery (R-I type) arising from the right coronary sinus with branches supplying the left coronary territory. The ECT results confirmed myocardial ischemia at the location of the absent left coronary artery. The ECT findings confirmed that ischemia was consistent with the vascular loss location in CAG images. In such anomalies, there is a compensatory widening of the coronary artery lumen. Medical treatment was administered, and the patient was discharged. CONCLUSION: Isolated single coronary arteries are associated with ischemia and potentially fatal acute coronary events. Hence, controlling risk factors is critical.

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