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1.
Sensors (Basel) ; 24(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38894239

RESUMO

OBJECTIVE: The aim was to evaluate and optimize the performance of sensor monitors in measuring PM2.5 and PM10 under typical emission scenarios both indoors and outdoors. METHOD: Parallel measurements and comparisons of PM2.5 and PM10 were carried out between sensor monitors and standard instruments in typical indoor (2 months) and outdoor environments (1 year) in Shanghai, respectively. The optimized validation model was determined by comparing six machining learning models, adjusting for meteorological and related factors. The intra- and inter-device variation, measurement accuracy, and stability of sensor monitors were calculated and compared before and after validation. RESULTS: Indoor particles were measured in a range of 0.8-370.7 µg/m3 and 1.9-465.2 µg/m3 for PM2.5 and PM10, respectively, while the outdoor ones were in the ranges of 1.0-211.0 µg/m3 and 0.0-493.0 µg/m3, correspondingly. Compared to machine learning models including multivariate linear model (ML), K-nearest neighbor model (KNN), support vector machine model (SVM), decision tree model (DT), and neural network model (MLP), the random forest (RF) model showed the best validation after adjusting for temperature, relative humidity (RH), PM2.5/PM10 ratios, and measurement time lengths (months) for both PM2.5 and PM10, in indoor (R2: 0.97 and 0.91, root-mean-square error (RMSE) of 1.91 µg/m3 and 4.56 µg/m3, respectively) and outdoor environments (R2: 0.90 and 0.80, RMSE of 5.61 µg/m3 and 17.54 µg/m3, respectively), respectively. CONCLUSIONS: Sensor monitors could provide reliable measurements of PM2.5 and PM10 with high accuracy and acceptable inter and intra-device consistency under typical indoor and outdoor scenarios after validation by RF model. Adjusting for both climate factors and the ratio of PM2.5/PM10 could improve the validation performance.

2.
Huan Jing Ke Xue ; 45(2): 1038-1048, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471941

RESUMO

In order to explore the pollution characteristics, ecological risks, and pollution sources of heavy metals in farmland soils around typical factories in Hunan Province, the content characteristics of eight heavy metals in farmland soils around fluoride factories, leather factories, and plating plants were analyzed. The geo-accumulation index and potential ecological risk index were used to evaluate the pollution and environmental risk of heavy metals. The correlation analysis, hierarchical cluster analysis, and principal component analysis were used to analyze the sources of heavy metals. The Monte-Carlo model was used to evaluate the probability risk of regional ecological risk. The results showed that the main pollution elements in the soil were Cd and Zn, and their mean values were 4.46 and 2.73 times the background values, respectively. Zn was at a mild pollution level in the soil of the three typical factories, and Cd was at a moderate pollution level in the whole fluoride factory. The pollution sources of heavy metals in the typical factories were mainly natural sources, industrial activity sources (industrial waste discharge, mineral mining, and smelting activities), traffic sources, etc. The results of potential ecological risk assessment showed that the ecological risk of the fluoride factory was at a high risk level, and the ecological risk of the leather factory and plating plants was at a high risk level. Cd was the main contributing element. The results of Monte-Carlo probabilistic ecological risk assessment reduced the uncertainty of deterministic assessment, which could provide scientific basis for accurate risk management and control in the regions.

3.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941285

RESUMO

This work describes the design and preliminary characterization of a novel portable hand exoskeleton for poststroke rehabilitation. The platform actively mobilizes the index-metacarpophalangeal (I-MCP) joint, and it additionally offers individual rigid support to distal degrees of freedom (DoFs) of the index and thumb. The test-bench characterization proves the capability of the device to render torques at the I-MCP level with high fidelity within frequencies of interest for the application (up to 3 Hz). The introduction of a feed-forward friction compensation at the actuator level lowers the output mechanical stiffness by 32%, contributing to a highly transparent behavior; moreover, the functionality of the platform in rendering different interaction strategies (patient/robot-in-charge) is tested with three healthy subjects, showing the potential of the device to provide assistance as needed.


Assuntos
Exoesqueleto Energizado , Reabilitação Neurológica , Humanos , Mãos , Polegar , Articulação Metacarpofalângica
4.
Toxics ; 11(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37112609

RESUMO

Pharmaceutical plants are an essential source of antibiotics emitted into the aqueous environment. The monitoring of target antibiotics in pharmaceutical plants through various regions is vital to optimize contaminant release. The occurrence, distribution, removal, and ecological risk of 30 kinds of selected antibiotics in 15 pharmaceutical plants in the Pearl River Delta (PRD) were investigated in this study. Lincomycin (LIN) showed the highest concentration (up to 56,258.3 ng/L) in the pharmaceutical plant influents from Zhongshan city. Norfloxacin (NFX) showed a higher detection frequency than other antibiotics. In addition, the spatial distribution of antibiotics in pharmaceutical plants showed significant differences, with higher concentrations of total antibiotics found in pharmaceutical plant influents in Shenzhen City than those of different regions in PRD. The treatment processes adopted by pharmaceutical plants were commonly ineffective in removing antibiotics, with only 26.7% of antibiotics being effectively removed (average removal greater than 70%), while 55.6% of antibiotics had removal rates of below 60%. The anaerobic/anoxic/oxic (AAO)-membrane bioreactor (MBR) combined process exhibited better treatment performance than the single treatment process. Sulfamethoxazole (SMX), ofloxacin (OFL), erythromycin-H2O (ETM-H2O), sulfadiazine (SDZ), sulfamethazine (SMZ), norfloxacin (NFX), and ciprofloxacin (CIP) in pharmaceutical plant effluents posed high or moderate ecological risk and deserve particular attention.

5.
Adv Sci (Weinh) ; 10(8): e2205435, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36683187

RESUMO

Subarachnoid hemorrhage (SAH) is a severe subtype of stroke caused by the rupturing of blood vessels in the brain. The ability to accurately assess the degree of bleeding in an SAH model is crucial for understanding the brain-damage mechanisms and developing therapeutic strategies. However, current methods are unable to monitor microbleeding owing to their limited sensitivities. Herein, a new bleeding assessment system using a bioprobe TTVP with aggregation-induced emission (AIE) characteristics is demonstrated. TTVP is a water-soluble, small-molecule probe that specifically interacts with blood. Taking advantage of its AIE characteristics, cell membranes affinity, and albumin-targeting ability, TTVP fluoresces in bleeding areas and detects the presence of blood with a high signal-to-noise (S/N) ratio. The degree of SAH bleeding in an endovascular perforation model is clearly evaluated based on the intensity of the fluorescence observed in the brain, which enables the ultrasensitive detection of mirco-bleeding in the SAH model in a manner that outperforms the current imaging strategies. This method serves as a promising tool for the sensitive analysis of the degree of bleeding in SAHs and other hemorrhagic diseases.


Assuntos
Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/etiologia , Encéfalo/metabolismo , Acidente Vascular Cerebral/complicações
6.
J Environ Manage ; 325(Pt B): 116637, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36419311

RESUMO

Coastal ecosystems offer substantial support and space for the sustainable development of human society, and hence the ecological risk evaluation of coastal ecosystems is of great significance. In this article, we propose an innovative framework for evaluating coastal ecological risk by considering oil spill risk information and environmental vulnerability information. Specifically, a deep learning based marine oil spill monitoring method is presented to obtain the oil spill risk information from Sentinel-1 polarimetric synthetic aperture radar (PolSAR) images. The environmental vulnerability information is then obtained from biological sample data and habitat information. Finally, a weighted probability model is introduced to utilize the oil spill risk and environmental vulnerability information, to evaluate the coastal ecological risk. In the experimental part, the proposed oil spill monitoring method shows its reliability in global ocean areas, and the proposed model is adopted to evaluate the ecological risk in Jiaozhou Bay, China. The results show that the ecological situation of more than half of the areas in Jiaozhou Bay is unstable, and the areas with high risk are mainly concentrated in the ports, shipping channels, and those areas with high biodiversity. This study provides some new perspectives on ecological risk assessment for coastal ecosystems, facilitating the planning process and the actions to be taken in response to the accidents that occur in the ocean, especially oil spill accidents.


Assuntos
Poluição por Petróleo , Humanos , Radar , Ecossistema , Reprodutibilidade dos Testes , Medição de Risco
7.
Front Cardiovasc Med ; 9: 1039313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330013

RESUMO

Objectives: Peripheral artery disease with calcification is extremely prevalent in the elderly. Due to the calcification, it requires a different clinical approach than the more common arteriosclerosis obliterans of the lower extremity. The introduction of novel technologies such as the drug-coated balloon, directional atherectomy, supera and drug-eluting stent has improved the prognosis of these patients. This study will contribute to the development of higher-quality evidence-based medicine for clinical treatment by assessing the quality of life (QOL), clinical treatment effect, and health economics of patients with calcification. Method and analysis: The Evolution study is designed as a prospective, multicenter, observational, real-world study. From January 2021 to December 2022, 600 patients with moderate to severe femoropopliteal artery calcification will be recruited from ten locations in China. After discharge, information on demographics, disease history, procedure details, imaging findings, and follow-up will be collected. Patients will undergo follow-up at 1, 6, 12, 18, and 24 months after operation. Technical success rate, vascular quality of life questionnaire, primary patency rate of the target lesion, clinically driven target lesion revascularization rate (CD-TLR), and health economics evaluation are all included as outcome measures. Conclusions: The Evolution study helps to investigate the clinical and financial results of various endovascular therapy modalities for patients with moderate and severe femoropopliteal artery calcification. These actual facts may help to harmonize therapy recommendations for peripheral artery disease. Clinical trial registration: The study protocol was registered at www.clinicaltrials.gov (registration number: NCT04716361).

8.
Front Oncol ; 11: 740410, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926255

RESUMO

OBJECTIVE: Craniopharyngiomas (CPs) predominantly involving the third ventricle were commonly termed "intraventricular" lesions. The aim of this study was to clarify the anatomical relationship between the tumor and the third ventricle by both surgical and histological investigation. METHODS: A retrospective review of primarily resected CPs by endoscopic endonasal surgery was performed. CPs with predominantly ventricular involvement were selected for study inclusion by preoperative imaging. The surgical procedure of each case was reviewed. The wholly removed tumor specimens were histologically analyzed, in all cases, to investigate the tumor-third ventricle relationship using hematoxylin and eosin, immunochemical, and immunofluorescence staining. RESULTS: Twenty-six primary CPs predominantly involving the third ventricle were selected from our series of 223 CPs treated by endoscopic endonasal surgery between January 2017 and March 2021. Gross-total resection was achieved in 24 (92.3%) of 26 patients, with achievement of near-total resection in the remaining patients. A circumferential layer of stretched third ventricle floor was identified surrounding the tumor capsule, which could be peeled off easily from the ventricle floor remnants at most areas of the plane of tumor attachment. Some portions of the tumor capsule tightly adhered to the third ventricle floor were removed together with the floor. A breach of various size was observed at the third ventricle floor after tumor removal in most cases, the floor remaining intact in only two cases (7.7%). Histological examination on marked portions of tumor capsule showed that the pia mater was frequently detected at most of the tumor-brain interface, except at the antero-frontal border of tumor contacting with the third ventricle floor. At this point, a layer of gliosis with various thickness was observed between the tumor and the neural tissue of the third ventricle floor. CONCLUSION: CPs with predominantly ventricular involvement should be considered as lesions with an extraventricular, epi-pia topography rather than "intraventricular" or "subpial" topography. Accurate understanding of the relationship between the third ventricle and such tumors would predict the circumferential cleavage plane of dissection, and remind neurosurgeons of performing dissection along the safe surgical plane to achieve total tumoral resection with minimizing hypothalamic damage.

9.
iScience ; 24(7): 102726, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34355141

RESUMO

Circadian protein oscillations are maintained by the lifelong repetition of protein production and degradation in daily balance. It comes at the cost of ever-replayed, futile protein synthesis each day. This biosynthetic cost with a given oscillatory protein profile is relievable by a rhythmic, not constant, degradation rate that selectively peaks at the right time of day but remains low elsewhere, saving much of the gross protein loss and of the replenishing protein synthesis. Here, our mathematical modeling reveals that the rhythmic degradation rate of proteins with circadian production spontaneously emerges under steady and limited activity of proteolytic mediators and does not necessarily require rhythmic post-translational regulation of previous focus. Additional (yet steady) post-translational modifications in a proteolytic pathway can further facilitate the degradation's rhythmicity in favor of the biosynthetic cost saving. Our work is supported by animal and plant circadian data, offering a generic mechanism for potentially widespread, time-dependent protein turnover.

10.
Int J Med Robot ; 11(2): 194-209, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24700686

RESUMO

BACKGROUND: Virtual-reality (VR) based simulation techniques offer an efficient and low cost alternative to conventional surgery training. This article describes a VR training and assessment system in laparoscopic rectum surgery. METHODS: To give a realistic visual performance of interaction between membrane tissue and surgery tools, a generalized cylinder based collision detection and a multi-layer mass-spring model are presented. A dynamic assessment model is also designed for hierarchy training evaluation. RESULTS: With this simulator, trainees can operate on the virtual rectum with both visual and haptic sensation feedback simultaneously. The system also offers surgeons instructions in real time when improper manipulation happens. The simulator has been tested and evaluated by ten subjects. CONCLUSIONS: This prototype system has been verified by colorectal surgeons through a pilot study. They believe the visual performance and the tactile feedback are realistic. It exhibits the potential to effectively improve the surgical skills of trainee surgeons and significantly shorten their learning curve.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Laparoscopia/métodos , Reto/cirurgia , Interface Usuário-Computador , Simulação por Computador , Procedimentos Cirúrgicos do Sistema Digestório/educação , Educação Médica Continuada/métodos , Humanos , Laparoscopia/educação , Curva de Aprendizado , Modelos Anatômicos , Projetos Piloto , Reto/anatomia & histologia
11.
Magn Reson Med ; 56(3): 517-26, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16902978

RESUMO

A temporal correlation (TC) mapping method is proposed to help bolus chasing during dynamic contrast-enhanced (DCE) MRI of complex pulmonary circulation (CPC) in patients with congenital heart disease. DCE-MRI was performed on five healthy male subjects (23-24 years old) and 25 patients (nine males and 16 females, 0.25-44 years old), and TC maps were generated by performing pixel-based computation of cross-correlations to the pulmonary artery with a series of time shifts in all subjects. Qualitative and quantitative evaluations were performed in comparison with original DCE images. TC maps exhibited a better signal-to-noise ratio (SNR) by factors of 4.3 and 1.3 in the lung parenchyma, pulmonary veins, and superior artery/vein; a better intraparenchymal contrast-to-noise ratio (CNR) by factors of 1.5-5.4; and a significantly higher conspicuity in all regions except the pulmonary arteries when graded with a five-point score. TC maps evaluated by two experienced clinicians significantly added relevant information (P<0.001), and in some cases affected the final diagnosis. We conclude that TC maps facilitate bolus chasing for DCE-MRI by reducing recirculation effects and interframe fluctuations, and hence complements morphological imaging of CPC in patients with complex congenital heart disease.


Assuntos
Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Aumento da Imagem/métodos , Pneumopatias/diagnóstico , Pneumopatias/etiologia , Imageamento por Ressonância Magnética/métodos , Circulação Pulmonar , Adolescente , Adulto , Criança , Pré-Escolar , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Lactente , Masculino
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