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1.
Opt Lett ; 49(9): 2229-2232, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691686

RESUMO

In this Letter, the CH3NH3PbBr3 nanocrystals (NCs) are embedded into the interstices of the fluorine (polyvinyl fluoride/polyvinylidene fluoride, PVF/PVDF) matrix on polyethylene terephthalate (PET) substrate to introduce new advantages, such as being flexible and waterproof, while maintaining the high optical performance of perovskites. The sample's photoluminescence (PL) spectra under 325 nm laser is a green emission peaked at 537 nm with full width at half maximum (FWHM) of about 21.2 nm and a fast PL decay time. As a color converter, it shows high optical absorption and can transform light from solar-blind ultraviolet to a blue region into a green region in air, water, and bending conditions. While excited by a 270 nm ultraviolet light-emitting diode (LED), the system's observed -3 dB bandwidth with the color converter is near 4.4 MHz in air and water conditions with well-eye diagrams at a data rate of 30 Mbps. Finally, we demonstrate an audio transmission application with an ultraviolet light source, a color conversion layer, and a low-cost silicon-based photodetector.

2.
Langmuir ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943597

RESUMO

Methylammonium lead halide perovskites with highly efficient pure-color or white-light generation have gained increasing scientific interest and promote the development of a great commercial opportunity in displays, lighting, and other applications. However, the poor stabilities, lead toxicity, and unfriendly solvents and ligands in the growth process severely restrict their commercial application. Here, we proposed a green method for preparing uniform and stable polymer-encapsulated photoluminescence (PL) tunable CH3NH3PbBr3-xClx NC thin films at room temperature. Utilizing the swelling effect between alcohol compounds and organic polymers and the ionization of NaCl in methanol solution, the anion exchange process can be achieved rapidly within 7 min. Moreover, the PL wavelengths of the CH3NH3PbBr3-xClx NCs films were precisely tuned with steps as fine as 2 nm. Experimental results showed that NaCl dissolved in methanol solution can form Cl-(CH3OH)n, which brings ionized Cl into the polymer-encapsulated CH3NH3PbBr3 NCs film for CH3NH3PbBr3-xClx NCs film growth. Based on the swelling and anion exchange dynamics, a modified NaCl-CH3OH-MABr solution system was developed to trigger CH3NH3PbBr3-xClx NCs film PL emission tuning from 528 to 463 nm with several-fold intensity enhancement. The realization of precisely controlled photoluminescence from the perovskite nanocrystal film would have wide applications in the optical and imaging fields.

3.
BMC Public Health ; 24(1): 1118, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654267

RESUMO

BACKGROUND: Many adolescents experience depression that often goes undetected and untreated. Identifying children and adolescents at a high risk of depression in a timely manner is an urgent concern. While the Children's Depression Inventory (CDI) is widely utilized in China, it lacks a localized revision or simplified version. With its 27 items requiring professional administration, the original CDI proves to be a time-consuming method for predicting children and adolescents with high depression risk. Hence, this study aimed to develop a shortened version of the CDI to predict high depression risk, thereby enhancing the efficiency of prediction and intervention. METHODS: Initially, backward elimination is conducted to identify various version of the short-form scales (e.g., three-item and five-item versions). Subsequently, the performance of five machine learning (ML) algorithms on these versions is evaluated using the area under the ROC curve (AUC) to determine the best algorithm. The chosen algorithm is then utilized to model the short-form scales, facilitating the identification of the optimal short-form scale based on predefined evaluation metrics. Following this, evaluation metrics are computed for all potential decision thresholds of the optimal short-form scale, and the threshold value is determined. Finally, the reliability and validity of the optimal short-form scale are assessed using a new sample. RESULTS: The study identified a five-item short-form CDI with a decision threshold of 4 as the most appropriate scale considering all assessment indicators. The scale had 81.48% fewer items than the original version, indicating good predictive performance (AUC = 0.81, Accuracy = 0.83, Recall = 0.76, Precision = 0.71). Based on the test of 315 middle school students, the results showed that the five-item CDI had good measurement indexes (Cronbach's alpha = 0.72, criterion-related validity = 0.77). CONCLUSIONS: This five-item short-form CDI is the first shortened and revised version of the CDI in China based on large local data samples.


Assuntos
Depressão , Aprendizado de Máquina , Humanos , Adolescente , Criança , Feminino , Masculino , China , Depressão/diagnóstico , Reprodutibilidade dos Testes , Escalas de Graduação Psiquiátrica/normas , Psicometria , Algoritmos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38518148

RESUMO

Objective: Currently, there is little information about the risk of sudden cardiac death and its predictors in aortic valve stenosis patients after transcatheter aortic valve replacement (TAVR). Therefore, we conducted a large sample cohort study on TAVR patients to evaluate the predictive factors and incidence of heart failure death caused by advanced heart failure (AHF) and sudden cardiac death. Furthermore, a nomogram model to predict its risk was constructed. Methods: This study retrospectively analyzed the data of 241 consecutive participants who had received TAVR treatment for aortic valve stenosis in our hospital from January 2020 to January 2022. The characteristics of the subjects, including myocardial zymogram, renal function, biochemical parameters, and cardiac ultrasound parameters, were collected. Moreover, a nomogram was constructed to predict the risk of sudden cardiac death and its predictors in patients after transcatheter aortic valve replacement (TAVR). The model was validatedinternally using measures of calibration and decision curve analysis. Results: Six independent risk factors(Age, smoking, diabetes, glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and fasting blood glucose) were finally recruited into the nomogram model to predict the risk of advanced heart failure and/or cardiogenic shock in AS patients treated by TAVR. Besides, the decision curve analysis and receiver operating characteristic curve indicated that the nomogram prediction models showed positive clinical benefits. Conclusions: The Age, smoking, diabetes, glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and fasting blood glucose are the independent risk factors for advanced heart failure and/or cardiogenic shock in AS patients treated by TAVR. The construction of nomograms is beneficial in predicting the risk of advanced heart failure and/or cardiogenic shock in AS patients treated by TAVR.

5.
Radiology ; 308(2): e222471, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37581504

RESUMO

Background Cerebral blood volume (CBV) maps derived from dynamic susceptibility contrast-enhanced (DSC) MRI are useful but not commonly available in clinical scenarios. Purpose To test image-to-image translation techniques for generating CBV maps from standard MRI sequences of brain tumors using the bookend technique DSC MRI as ground-truth references. Materials and Methods A total of 756 MRI examinations, including quantitative CBV maps produced from bookend DSC MRI, were included in this retrospective study. Two algorithms, the feature-consistency generative adversarial network (GAN) and three-dimensional encoder-decoder network with only mean absolute error loss, were trained to synthesize CBV maps. The performance of the two algorithms was evaluated quantitatively using the structural similarity index (SSIM) and qualitatively by two neuroradiologists using a four-point Likert scale. The clinical value of combining synthetic CBV maps and standard MRI scans of brain tumors was assessed in several clinical scenarios (tumor grading, prognosis prediction, differential diagnosis) using multicenter data sets (four external and one internal). Differences in diagnostic and predictive accuracy were tested using the z test. Results The three-dimensional encoder-decoder network with T1-weighted images, contrast-enhanced T1-weighted images, and apparent diffusion coefficient maps as the input achieved the highest synthetic performance (SSIM, 86.29% ± 4.30). The mean qualitative score of the synthesized CBV maps by neuroradiologists was 2.63. Combining synthetic CBV with standard MRI improved the accuracy of grading gliomas (standard MRI scans area under the receiver operating characteristic curve [AUC], 0.707; standard MRI scans with CBV maps AUC, 0.857; z = 15.17; P < .001), prediction of prognosis in gliomas (standard MRI scans AUC, 0.654; standard MRI scans with CBV maps AUC, 0.793; z = 9.62; P < .001), and differential diagnosis between tumor recurrence and treatment response in gliomas (standard MRI scans AUC, 0.778; standard MRI scans with CBV maps AUC, 0.853; z = 4.86; P < .001) and brain metastases (standard MRI scans AUC, 0.749; standard MRI scans with CBV maps AUC, 0.857; z = 6.13; P < .001). Conclusion GAN image-to-image translation techniques produced accurate synthetic CBV maps from standard MRI scans, which could be used for improving the clinical evaluation of brain tumors. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Branstetter in this issue.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Volume Sanguíneo Cerebral , Estudos Retrospectivos , Recidiva Local de Neoplasia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Glioma/patologia
6.
BMC Anesthesiol ; 23(1): 290, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626303

RESUMO

BACKGROUND: Partial neuromuscular blockade (NMB) has been applied for some surgeries to reduce bleeding and prevent patient movement for spinal surgery. Sugammadex selectively binds to rocuronium in the plasma and consequently lowers the rocuronium concentration at the neuromuscular junction. In this study, we aimed to observe whether the success rate of transcranial motor-evoked potential (TceMEP) can be increased by sugammadex compared with partial NMB during spinal surgery. METHODS: Patients who underwent elective spinal surgery with TceMEP monitoring were randomly assigned to the sugammadex group and control group. Rocuronium was continuously infused to maintain the train of four counts (TOFc) = 2. The sugammadex group discontinued rocuronium infusion at the time of TceMEP monitoring and was infused with 2 mg/kg sugammadex; the control group was infused with the same dose of saline. RESULTS: A total of 171 patients were included. The success rate of TceMEP monitoring in the sugammadex group was significantly higher than that in the control group. TceMEP amplitudes were greater in the sugammadex group than in the control group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. The latencies of upper extremity TceMEPs monitoring showed no difference between groups. TOF ratios were greater in the sugammadex group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. There were no adverse effects caused by sugammadex. CONCLUSIONS: Sugammadex can improve the success rate of motor-evoked potential monitoring compared with moderate neuromuscular blockade induced by continuous infusion of rocuronium in spinal surgery. TRIAL REGISTRATION: The study was registered on clinicaltrials.gov.cn on 29/10/2020 (trial registration number: NCT04608682).


Assuntos
Potencial Evocado Motor , Doenças Neuromusculares , Humanos , Rocurônio , Sugammadex/farmacologia , Relaxamento Muscular
7.
Molecules ; 28(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36985790

RESUMO

As flexible wearable devices, hydrogel sensors have attracted extensive attention in the field of soft electronics. However, the application or long-term stability of conventional hydrogels at extreme temperatures remains a challenge due to the presence of water. Antifreezing and antidrying ionic conductive organohydrogels were prepared using cellulose nanocrystals and gelatin as raw materials, and the hydrogels were prepared in a water/glycerol binary solvent by a one-pot method. The prepared hydrogels were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The mechanical properties, electrical conductivity, and sensing properties of the hydrogels were studied by means of a universal material testing machine and LCR digital bridge. The results show that the ionic conductive hydrogel exhibits high stretchability (elongation at break, 584.35%) and firmness (up to 0.16 MPa). As the binary solvent easily forms strong hydrogen bonds with water molecules, experiments show that the organohydrogels exhibit excellent freezing and drying (7 days). The organohydrogels maintain conductivity and stable sensitivity at a temperature range (-50 °C-50 °C) and after long-term storage (7 days). Moreover, the organohydrogel-based wearable sensors with a gauge factor of 6.47 (strain, 0-400%) could detect human motions. Therefore, multifunctional organohydrogel wearable sensors with antifreezing and antidrying properties have promising potential for human body monitoring under a broad range of environmental conditions.

8.
Molecules ; 28(22)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38005275

RESUMO

Cadmium (Cd) pollution in wastewater has become an increasingly widespread concern worldwide. Studies on Cd (II) removal using phosphate-adsorbed sorbents are limited. This study aimed to elucidate the behaviors and mechanisms of Cd (II) sorption on phosphate-loaded Ca-Mn-impregnated biochar (Ps-CMBC). The Cd (II) sorption on Ps-CMBC reached equilibrium within 2 h and exhibited a higher sorption efficiency than biochar and CMBC. Additionally, the Langmuir isotherm could better describe the Cd (II) adsorption on the sorbents. P75-CMBC had a maximum Cd (II) sorption capability of 70.13 mg·g-1 when fitted by the Langmuir isotherm model, which was approximately 3.18 and 2.86 times greater than those of biochar and CMBC, respectively. Higher pH (5-7) had minimal effect on Cd (II) sorption capacity. The results of characterization analyses, such as SEM-EDS, FTIR, and XPS, suggested that there was a considerable difference in the sorption mechanisms of Cd (II) among the sorbents. The primary sorption mechanisms for biochar, CMBC, and Ps-CMBC included electrostatic attraction and surface complexation; additionally, for Ps-CMBC, Cd (II)-π interactions and coordination of Cd (II) with P=O were critical mechanisms for Cd (II) removal. The results of this study demonstrate that phosphate-loaded CMBC can be used as an effective treatment for heavy metal pollution in aqueous media.


Assuntos
Cádmio , Poluentes Químicos da Água , Cádmio/química , Poluentes Químicos da Água/química , Cinética , Carvão Vegetal/química , Água , Adsorção , Fosfatos
9.
Small ; 18(17): e2107951, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35355404

RESUMO

Silica glasses have wide applications in industrial fields due to their extraordinary properties, such as high transparency, low thermal expansion coefficient, and high hardness. However, current methods of fabricating silica glass generally require long thermal treatment time (up to hours) and complex setups, leading to high cost and slow manufacturing speed. Herein, to obtain high-quality glasses using a facile and rapid method, an ultrafast high-temperature sintering (UHS) technique is reported that requires no additional pressure. Using UHS, silica precursors can be densified in seconds due to the large heating rate (up to 102 K s-1 ) of closely placed carbon heaters. The typical sintering time is as short as ≈10 s, ≈1-3 orders of magnitude faster than other methods. The sintered glasses exhibit relative densities of > 98% and high visible transmittances of ≈90%. The powder-based sintering process also allows rapid doping of metal ions to fabricate colored glasses. The UHS is further extended to sinter other functional glasses such as indium tin oxide (ITO)-doped silica glass, and other transparent ceramics such as Gd-doped yttrium aluminum garnet. This study demonstrates an UHS proof-of-concept for the rapid fabrication of high-quality glass and opens an avenue toward rapid discovery of transparent materials.

10.
Cancer Cell Int ; 22(1): 411, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36527013

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most malignant, aggressive and recurrent primary brain tumor. Cell senescence can cause irreversible cessation of cell division in normally proliferating cells. According to studies, senescence is a primary anti-tumor mechanism that may be seen in a variety of tumor types. It halts the growth and spread of tumors. Tumor suppressive functions held by cellular senescence provide new directions and pathways to promote cancer therapy. METHODS: We comprehensively analyzed the cell senescence-associated genes expression patterns. The potential molecular subtypes were acquired based on unsupervised cluster analysis. The tumor immune microenvironment (TME) variations, immune cell infiltration, and stemness index between 3 subtypes were analyzed. To identify genes linked with GBM prognosis and build a risk score model, we used weighted gene co-expression network analysis (WGCNA), univariate Cox regression, Least absolute shrinkage and selection operator regression (LASSO), and multivariate Cox regression analysis. And the correlation between risk scores and clinical traits, TME, GBM subtypes, as well as immunotherapy responses were estimated. Immunohistochemistry (IHC) and cellular experiments were performed to evaluate the expression and function of representative genes. Then the 2 risk scoring models were constructed based on the same method of calculation whose samples were acquired from the CGGA dataset and TCGA datasets to verify the rationality and the reliability of the risk scoring model. Finally, we conducted a pan-cancer analysis of the risk score, assessed drug sensitivity based on risk scores, and analyzed the pathways of sensitive drug action. RESULTS: The 3 potential molecular subtypes were acquired based on cell senescence-associated genes expression. The Log-rank test showed the difference in GBM patient survival between 3 potential molecular subtypes (P = 0.0027). Then, 11 cell senescence-associated genes were obtained to construct a risk-scoring model, which was systematically randomized to distinguish the train set (n = 293) and the test set (n = 292). The Kaplan-Meier (K-M) analyses indicated that the high-risk score in the train set (P < 0.0001), as well as the test set (P = 0.0053), corresponded with poorer survival. In addition, the high-risk score group showed a poor response to immunotherapy. The reliability and credibility of the risk scoring model were confirmed according to the CGGA dataset, TCGA datasets, and Pan-cancer analysis. According to drug sensitivity analysis, it was discovered that LJI308, a potent selective inhibitor of RSK pathways, has the highest drug sensitivity. Moreover, the GBM patients with higher risk scores may potentially be more beneficial from drugs that target cell cycle, mitosis, microtubule, DNA replication and apoptosis regulation signaling. CONCLUSION: We identified potential associations between clinical characteristics, TME, stemness, subtypes, and immunotherapy, and we clarified the therapeutic usefulness of cell senescence-associated genes.

11.
Chem Rev ; 120(10): 4257-4300, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32271022

RESUMO

Solid-state batteries with desirable advantages, including high-energy density, wide temperature tolerance, and fewer safety-concerns, have been considered as a promising energy storage technology to replace organic liquid electrolyte-dominated Li-ion batteries. Solid-state electrolytes (SSEs) as the most critical component in solid-state batteries largely lead the future battery development. Among different types of solid-state electrolytes, garnet-type Li7La3Zr2O12 (LLZO) solid-state electrolytes have particularly high ionic conductivity (10-3 to 10-4 S/cm) and good chemical stability against Li metal, offering a great opportunity for solid-state Li-metal batteries. Since the discovery of garnet-type LLZO in 2007, there has been an increasing interest in the development of garnet-type solid-state electrolytes and all solid-state batteries. Garnet-type electrolyte has been considered one of the most promising and important solid-state electrolytes for batteries with potential benefits in energy density, electrochemical stability, high temperature stability, and safety. In this Review, we will survey recent development of garnet-type LLZO electrolytes with discussions of experimental studies and theoretical results in parallel, LLZO electrolyte synthesis strategies and modifications, stability of garnet solid electrolytes/electrodes, emerging nanostructure designs, degradation mechanisms and mitigations, and battery architectures and integrations. We will also provide a target-oriented research overview of garnet-type LLZO electrolyte and its application in various types of solid-state battery concepts (e.g., Li-ion, Li-S, and Li-air), and we will show opportunities and perspectives as guides for future development of solid electrolytes and solid-state batteries.

12.
J Nanobiotechnology ; 20(1): 195, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35443708

RESUMO

BACKGROUND: The rapid spread of infectious bacteria has brought great challenges to public health. It is imperative to explore effective and environment-friendly antibacterial modality to defeat antibiotic-resistant bacteria with high biosafety and broad-spectrum antibacterial property. RESULTS: Herein, biocompatible Cu3SnS4 nanoflakes (NFs) were prepared by a facile and low-cost fabrication procedure. These Cu3SnS4 NFs could be activated by visible light, leading to visible light-mediated photocatalytic generation of a myriad of reactive oxygen species (ROS). Besides, the plasmonic Cu3SnS4 NFs exhibit strong near infrared (NIR) absorption and a high photothermal conversion efficiency of 55.7%. The ROS mediated cellular oxidative damage and the NIR mediated photothermal disruption of bacterial membranes collaboratively contributed to the advanced antibacterial therapy, which has been validated by the efficient eradication of both Gram-negative Escherichia coli and Gram-positive methicillin-resistant Staphylococcus aureus strains in vitro and in vivo. Meanwhile, the exogenous copper ions metabolism from the Cu3SnS4 NFs facilitated the endothelial cell angiogenesis and collagen deposition, thus expediting the wound healing. Importantly, the inherent localized surface plasmon resonance effect of Cu3SnS4 NFs empowered them as an active substrate for surface-enhanced Raman scattering (SERS) imaging and SERS-labeled bacteria detection. CONCLUSIONS: The low cost and biocompatibility together with the solar-driven broad-spectrum photocatalytic/photothermal antibacterial property of Cu3SnS4 NFs make them a candidate for sensitive bacteria detection and effective antibacterial treatment.


Assuntos
Hipertermia Induzida , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Espécies Reativas de Oxigênio
13.
BMC Musculoskelet Disord ; 23(1): 1112, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36544111

RESUMO

BACKGROUND: The purpose of this study was to evaluate the effect of varying the different correction angles of hindfoot osteotomy orthosis on the biomechanical changes of the adjacent joints after triple arthrodesis in adult patients with stiff clubfoot to determine the optimal hindfoot correction angle and provide a biomechanical basis for the correction of hindfoot deformity in patients with stiff clubfoot. METHODS: A 26-year-old male patient with a stiff left clubfoot was selected for the study, and his ankle and foot were scanned using dual-source computed tomography. A three-dimensional finite element model of the ankle was established, and after the validity of the model was verified by plantar pressure experiments, triple arthrodesis was simulated to analyze the biomechanical changes of the adjacent joints under the same load with "3°" of posterior varus, "0°" of a neutral position and "3°, 6°, 9°" of valgus as the correction angles. RESULTS: The peak plantar pressure calculated by the finite element model of the clubfoot was in good agreement with the actual plantar pressure measurements, with an error of less than 1%. In triple arthrodesis, the peak von Mises stress in the adjacent articular cartilage was significantly different and less than the preoperative stress when the corrected angle of the hindfoot was valgus "6°". In comparison, the peak von Mises stress in the adjacent articular cartilage was not significantly different in varus "3°", neutral "0°", valgus "3°" and valgus "9°" compared with the preoperative stress. CONCLUSION: The results of this study showed that different angles of hindfoot correction in triple arthrodesis did not increase the peak von Mises stress in the adjacent joints, which may not lead to the development of arthritis in the adjacent joint, and a hindfoot correction angle of "6°" of valgus significantly reduced the peak von Mises stress in the adjacent joints after triple arthrodesis.


Assuntos
Pé Torto Equinovaro , Adulto , Masculino , Humanos , Pé Torto Equinovaro/diagnóstico por imagem , Pé Torto Equinovaro/cirurgia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Tornozelo , Artrodese/métodos , Extremidade Inferior , Fenômenos Biomecânicos
14.
Vascular ; 30(3): 474-480, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34080448

RESUMO

OBJECTIVES: Research in the field of lower extremity vascular disease has increased in popularity over the years. To adequately characterize and validate the effectiveness of vascular interventions, in vivo experimentation in large animals is required. Thus, it is necessary to find a method to detect the shape and density of blood vessels in the lower extremities that can evaluate and verify the treatment measures' effectiveness and have high accuracy and repeatability. This study characterized factors that determined both the accuracy and overall value of digital subtraction angiography in lower limb arteriography using a canine animal model. METHODS: Six beagle dogs were anesthetized and immobilized on the motorized table. The femoral artery was accessed using an indwelling needle. A bolus of contrast agent was injected into the access site, and digital subtraction angiography with bolus chase technology was used to collect contrast images for analysis. At the end of the procedure, the anesthetized dogs were euthanized using an overdose of potassium chloride. After confirming the euthanasia of the dogs, the cadavers were taken to the experimental animal center of Xinjiang Medical University and processed by qualified institutional personnel. RESULTS: The final arteriographic images of the hind limbs from all six dogs were precise, and the branches of small vessels could be distinguished without any visible artifacts. CONCLUSIONS: These results suggested that arteriography using digital subtraction angiography could reveal the shape and density of blood vessels in canine animal models. This method has great potential to significantly improve research related to limb ischemia due to its simple and reproducible results.


Assuntos
Isquemia , Extremidade Inferior , Angiografia Digital/métodos , Animais , Cães , Artéria Femoral/diagnóstico por imagem , Membro Posterior , Humanos , Isquemia/diagnóstico por imagem , Extremidade Inferior/irrigação sanguínea
15.
BMC Med Educ ; 22(1): 469, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35710473

RESUMO

BACKGROUND: Constructivism theory has suggested that constructing students' own meaning is essential to successful learning. The erroneous example can easily trigger learners' confusion and metacognition, which may "force" students to process the learning material and construct meaning deeply. However, some learners exhibit a low level of elaboration activity and spend little time on each example. Providing instructional scaffolding and elaboration training may be an efficient method for addressing this issue. The current study conducted a randomized controlled trial to examine the effectiveness of erroneous example elaboration training on learning outcomes and the mediating effects of metacognitive load for Chinese students in medical statistics during the COVID-19 pandemic. METHODS: Ninety-one third-year undergraduate medical students were randomly assigned to the training group (n = 47) and the control group (n = 44). Prerequisite course performance and learning motivation were collected as covariates. The mid-term exam and final exam were viewed as posttest and delayed-test to make sure the robustness of the training effect. The metacognitive load was measured as a mediating variable to explain the relationship between the training and academic performance. RESULTS: The training significantly improved both posttest and delayed-test performance compared with no training (Fposttest = 26.65, p < 0.001, Partial η2 = 0.23; Fdelayed test = 38.03, p < 0.001, Partial η2 = 0.30). The variation trend in metacognitive load in the two groups was significantly different (F = 2.24, p < 0.05, partial η2 = 0.20), but metacognitive load could not explain the positive association between the treatment and academic performance (ß = - 0.06, se = 0.24, 95% CI - 0.57 to 0.43). CONCLUSIONS: Erroneous example learning and metacognitive demonstrations are effective for academic performance in the domain of medical statistics, but their underlying mechanism merits further study.


Assuntos
COVID-19 , Estudantes de Medicina , China , Humanos , Pandemias , Saúde Pública , Estudantes de Medicina/psicologia
16.
Foot Ankle Surg ; 28(4): 514-517, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35227590

RESUMO

PURPOSE: This study aimed to detect the effect of a modified chevron osteotomy on hallux valgus (HV) deformity at five-year follow up. METHODS: Twenty patients with symptomatic HV who underwent modified chevron osteotomy between June 2014 and January 2016 were included in the present study. The minimum follow-up duration was five years. Each patient was evaluated preoperatively, six weeks postoperatively and five years postoperatively using the visual analog scale (VAS) pain score, the American Orthopedic Foot & Ankle Society (AOFAS) score and cosmetic and radiological outcomes. RESULTS: The AOFAS score improved from 54.40 ( ± 4.58) preoperatively to 94.30 ( ± 2.15) six weeks postoperatively (p < 0.001) and 96.95 ( ± 1.54) five years postoperatively (p < 0.001). The VAS scores decreased from 6.30 ( ± 1.17) preoperatively to 0.15 ( ± 0.37) five years postoperatively (p < 0.001). The mean intermetatarsal angle improved from 16.00° ( ± 2.20°) preoperatively to 4.15° ( ± 1.22°) six weeks postoperatively (p < 0.001) and 4.40° ( ± 1.39°) five years postoperatively (p < 0.001). The mean HV angle also improved, from 32.70° ( ± 5.34°) preoperatively to 4.80° ( ± 1.40°) six weeks postoperatively (p < 0.001) and 5.20° ( ± 1.32°) five years postoperatively (p < 0.001). The cosmetic results were either excellent or good in 19 patients (95%). There was no recurrence in this study during the five postoperative years. CONCLUSION: A modified chevron osteotomy can achieve successful correction of moderate-to-severe HV, with excellent outcomes at five-year follow up.


Assuntos
Joanete , Hallux Valgus , Hallux , Hallux/cirurgia , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Humanos , Osteotomia/métodos , Resultado do Tratamento
17.
Small ; 17(40): e2008200, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34496143

RESUMO

The combination of good stability, biocompatibility, and high mechanical strength is attractive for bio-related material applications, but it remains challenging to simultaneously achieve these properties in a single, ionically conductive material. Here a "wood" ionic cable, made of aligned wood nanofibrils, demonstrating a combination of biocompatibility, high mechanical strength, high ionic conductivity, and excellent stability is reported. The wood ionic cable possesses excellent flexibility and exhibits high tensile strength up to 260 MPa (in the dry state) and ≈80 MPa (in the wet state). The nanochannels within the highly aligned cellulose nanofibrils and the presence of negative charges on the surfaces of these nanochannels, originating from the cellulose hydroxyl groups, provide new opportunities for ion regulation at low salt concentrations. Ion regulation in turn enables the wood ionic cable to have unique nanofluidic ionic behaviors. The Na+ ion conductivity of the wood ionic cable can reach up to ≈1.5 × 10-4 S cm-1 at low Na+ ion concentration (1.0 × 10-5 mol L-1 ), which is an order of magnitude higher than that of bulk NaCl solution at the same concentration. The scalable, biocompatible wood ionic cable enables novel ionic device designs for potential ion-regulation applications.


Assuntos
Celulose , Madeira , Hidrogéis , Íons , Resistência à Tração
18.
Appl Opt ; 60(19): 5480-5487, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263834

RESUMO

Baijiu is a traditional and popular Chinese liquor with enormous sale potential, which is affected by factors such as flavor and storage time. Chinese Baijiu is a complex and transparent mixture that makes analyzing difficult. The utility of time-resolved fluorescence helped to develop a new method to analyze Baijiu. Forty-two Baijiu samples among six brands with three flavors were prepared, and their fluorescence spectra were analyzed with an excitation light of 374.2 nm. Hexanoic acid and ethyl butyrate were found to have an impact on Baijiu fluorescence. The properties of lifetimes in Baijiu were investigated, and its mechanism was studied by calculations through density function theory. Using parameters of fluorescence lifetimes, Baijiu samples were classified according to their flavors. Additionally, the correlations between fluorescence lifetimes and storage time of Baijiu in Luzhou flavor were obtained, leading to a reliable and efficient method to establish the year forecast model of Chinese Baijiu with a mean error of 2.79 months. It also provides an important reference of the utility of time-resolved fluorescence for quantitative research of multi-component systems.


Assuntos
Bebidas Alcoólicas/análise , Aromatizantes/análise , Fluorimunoensaio/métodos , Análise de Alimentos/métodos , Paladar/fisiologia , Compostos Orgânicos Voláteis/química , China
19.
Br J Neurosurg ; 35(2): 209-215, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32567379

RESUMO

OBJECTIVE: The purpose of this study was to present our experience in the management of ruptured intracranial aneurysms associated with moyamoya disease (MMD), and to discuss their treatment strategies and the timing of revascularization surgery. PATIENTS AND METHODS: Thirteen patients who had ruptured intracranial aneurysms associated with MMD were enrolled in this study. Different treatment strategies were adopted based on the location of the aneurysms. Their clinical and radiologic features, treatment selection and outcomes were retrospectively reviewed. RESULTS: Among the five patients with major artery aneurysms in anterior circulation, three were embolized and two clipped. Among the five patients with major artery aneurysms in posterior circulation, three were treated by endovascular coiling. Among the three peripheral aneurysms, one was treated by endovascular embolization, one by aneurysmectomy, and the other one by revascularization alone. For the patients whose aneurysms were treated by endovascular embolization or surgery, a staged revascularization was performed on day 28 to day 87 after the first operation. For the two patients with aneurysms untreated directly, the timing of revascularization was 20 days and 54 days after hemorrhage, respectively. During the follow-up recurrent intracranial hemorrhage occurred in a patient, but not caused by the previous aneurysm. No other patients suffered recurrent intracranial hemorrhage or ischemic stroke. Complete occlusion was achieved in all the 11 aneurysms that had been clipped or embolized. Of the remaining three aneurysms that had not been directly treated, one disappeared spontaneously, whereas the other two remained stable. The direct and indirect bypasses were confirmed patent in the 11 patients who had undergone revascularization. CONCLUSION: Our current treatment strategies and timing of revascularization may provide a benefit for the patients with MMD accompanied by ruptured intracranial aneurysms.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , Doença de Moyamoya , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Angiografia Cerebral , Seguimentos , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
20.
Sensors (Basel) ; 21(8)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917034

RESUMO

Facial recognition has attracted more and more attention since the rapid growth of artificial intelligence (AI) techniques in recent years. However, most of the related works about facial reconstruction and recognition are mainly based on big data collection and image deep learning related algorithms. The data driven based AI approaches inevitably increase the computational complexity of CPU and usually highly count on GPU capacity. One of the typical issues of RGB-based facial recognition is its applicability in low light or dark environments. To solve this problem, this paper presents an effective procedure for facial reconstruction as well as facial recognition via using a depth sensor. For each testing candidate, the depth camera acquires a multi-view of its 3D point clouds. The point cloud sets are stitched for 3D model reconstruction by using the iterative closest point (ICP). Then, a segmentation procedure is designed to separate the model set into a body part and head part. Based on the segmented 3D face point clouds, certain facial features are then extracted for recognition scoring. Taking a single shot from the depth sensor, the point cloud data is going to register with other 3D face models to determine which is the best candidate the data belongs to. By using the proposed feature-based 3D facial similarity score algorithm, which composes of normal, curvature, and registration similarities between different point clouds, the person can be labeled correctly even in a dark environment. The proposed method is suitable for smart devices such as smart phones and smart pads with tiny depth camera equipped. Experiments with real-world data show that the proposed method is able to reconstruct denser models and achieve point cloud-based 3D face recognition.


Assuntos
Inteligência Artificial , Imageamento Tridimensional , Algoritmos , Face , Humanos
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