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1.
Food Res Int ; 188: 114502, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823845

RESUMO

Lycium barbarum L. berries have a remarkable chemical composition and extensive biological activities, being a valuable component of health and nutraceutical practices. Nevertheless, a deep insight on the intestinal permeation of the pro-healthy bioactive compounds is urgently needed to predict the real effects on human body. This study attempted, for the first time, to optimize the Ultrasound-Assisted Extraction (UAE) of goji berries using a Response Surface Methodology approach and establish the intestinal permeation of the principal pro-healthy compounds. The optimal extraction conditions were a solid:liquid ratio of 8.75 % for 56.21 min, using an intensity of 59.05 W/m2. The optimal extract displayed a remarkable antioxidant capacity, with LC/DAD-ESI-MS analysis unveiled a diverse phytochemical profile, encompassing different compounds (e.g. glu-lycibarbarspermidine F, 2-glu-kukoamine, rutin, 3,5-dicaffeoylquinic acid). The intestinal co-culture model demonstrated that glu-lycibarbarspermidine F (isomer 2) (73.70 %), 3,5-dicaffeoylquinic acid (52.66 %), and isorhamnetin-3-O-rutinoside (49.31 %) traversed the intestinal cell layer, exerting beneficial health-promoting effects.


Assuntos
Antioxidantes , Frutas , Lycium , Extratos Vegetais , Lycium/química , Frutas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Humanos , Permeabilidade , Ondas Ultrassônicas , Compostos Fitoquímicos/isolamento & purificação , Mucosa Intestinal/metabolismo , Células CACO-2 , Absorção Intestinal , Rutina/isolamento & purificação , Ultrassom/métodos , Função da Barreira Intestinal
2.
Int J Pharm ; 655: 124049, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38537921

RESUMO

In in-process quality monitoring for Continuous Manufacturing (CM) and Critical Quality Attributes (CQA) assessment for Real-time Release (RTR) testing, ultrasonic characterization is a critical technology for its direct, non-invasive, rapid, and cost-effective nature. In quality evaluation with ultrasound, relating a pharmaceutical tablet's ultrasonic response to its defect state and quality parameters is essential. However, ultrasonic CQA characterization requires a robust mathematical model, which cannot be obtained with traditional first principles-based modeling approaches. Machine Learning (ML) using experimental data is emerging as a critical analytical tool for overcoming such modeling challenges. In this work, a novel Deep Neural Network-based ML-driven Non-Destructive Evaluation (ML-NDE) modeling framework is developed, and its effectiveness for extracting and predicting three CQAs, namely defect states, compression force levels, and amounts of disintegrant, is demonstrated. Using a robotic tablet handling experimental rig, each attribute's distinct waveform dataset was acquired and utilized for training, validating, and testing the respective ML models. This study details an advanced algorithmic quality assessment framework for pharmaceutical CM in which automated RTR testing is expected to be critical in developing cost-effective in-process real-time monitoring systems. The presented ML-NDE approach has demonstrated its effectiveness through evaluations with separate (unused) test datasets.


Assuntos
Tecnologia Farmacêutica , Ultrassom , Fenômenos Mecânicos , Pressão , Comprimidos
3.
J Sci Food Agric ; 104(10): 5689-5697, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372563

RESUMO

BACKGROUND: To manage industrial waste in accordance with the circular bioeconomy concept it is sometimes necessary to handle grape seeds, an abundant by-product of the wine-making process. This study presents a process based on ultrasound technology for the extraction of grape-seed proteins, due to their nutritional and techno-functional properties. The protein content of extracts obtained under silent and lab-scale conditions was compared with that obtained under semi-industrial ultrasound conditions, and the chemical composition (carbohydrates, total phenols, and lipids) and the elemental profiles of the final, up-scaled downstream extracts were characterized. RESULTS: This work found that the maximum amount of protein in the final product was 378.31 g.kg-1 of the extract. Chemical characterization revealed that each 1 kg of extract had an average content of 326.19 g gallic acid equivalent as total phenols, 162.57 g glucose equivalent as carbohydrates, and 382.76 g of lipophilic compounds. Furthermore, when the extract was checked for hazardous elements, none were found in levels that could be considered a risk for human health. CONCLUSION: The proposed semi-industrial strategy has the potential to contribute greatly to the valorization of grape seeds through the preparation of a protein-rich extract that can be used as an alternative to synthetic wine stabilizers and for the development of novel food and nutraceutical products. © 2024 Society of Chemical Industry.


Assuntos
Proteínas de Plantas , Sementes , Vitis , Vitis/química , Sementes/química , Proteínas de Plantas/química , Proteínas de Plantas/análise , Fenóis/química , Fenóis/análise , Resíduos Industriais/análise , Resíduos Industriais/economia , Ultrassom/métodos , Vinho/análise , Manipulação de Alimentos/métodos , Extratos Vegetais/química
4.
Plant Signal Behav ; 19(1): 2310974, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38345027

RESUMO

Plants have been observed to produce short ultrasonic emissions (UEs), and current research is focusing on developing noninvasive techniques for recording and analyzing these emissions. A standardized methodology has not been established yet; in this paper we suggest a cost-effective procedure for recording, extracting, and identifying plant UEs using only a single ultrasound microphone, a laptop computer, and open-source software.


Assuntos
Acústica , Ultrassom , Análise Custo-Benefício , Plantas
5.
Eur Endod J ; 9(2): 146 - 153, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38219029

RESUMO

OBJECTIVE: To compare the effectiveness of lateral canal irrigation penetration by conventional needle, passive ultrasonic, sonic endo activator, and Erbium laser (2780nm). METHODS: A total of 40 palatal roots of human maxillary first molars were collected and instrumented at a working length of 12 mm by an X1-X4 rotary Protaper Next system (Dentsply, Maillefer, Ballaigues, Switzerland) using the crown-down technique. Artificial lateral canals were made at 2, 4, and 6 mm from the apex on mesial and distal sides using an ISO rotary reamer (Dentsply, Maillefer, Ballaigues, Switzerland; #10 for mesial, #08 for distal). The samples were then cleared using methyl salicylate. A solution of black ink and normal saline was used as an irrigant for the root canal. The percentages of the penetration of the ink into the lateral canals were measured using a stereomicroscope (Q-Scope, Arnhem, The Netherlands) with the aid of program Image J. The Tukey test is used to assess the significant difference between intragroup and intergroup comparisons of different thirds, and the T-test is used to assess the significant difference between every two groups and for the mesial and distal sides of each group. The level of significance was set at 0.05. RESULTS: Results showed that none of the activation techniques used resulted in complete lateral canal penetrations; however, on both sides at all thirds, the Erbium laser (2780 nm) achieved the highest results with a highly significant statistical difference (p=0.05) with all other groups, and the least penetration was in the conventional needle group. CONCLUSION: The size of the lateral canal is a restricting factor for all activation methods; the best results can be achieved by laser. Conventional needles cannot be used alone to disinfect complex canal anatomy; however, passive ultrasonic and sonic endo activator activations can produce comparable results.


Assuntos
Cavidade Pulpar , Érbio , Polimetil Metacrilato , Humanos , Érbio/farmacologia , Preparo de Canal Radicular/métodos , Ultrassom
6.
Int J Cardiol ; 400: 131765, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211669

RESUMO

BACKGROUND: Ultrasonic flow ratio (UFR) is a novel intravascular ultrasound (IVUS)-derived modality for fast computation of fractional flow reserve (FFR) without pressure wires and adenosine. AIMS: This study was sought to compare the diagnostic performance of UFR and quantitative flow ratio (QFR), using FFR as the reference standard. METHODS: This is a retrospective study enrolling consecutive patients with intermediate coronary artery lesions (diameter stenosis of 30%-90% by visual estimation) for IVUS and FFR measurement. UFR and QFR were performed offline in a core-lab by independent analysts blinded to FFR. RESULTS: From December 2022 to May 2023, a total of 78 eligible patients were enrolled. IVUS and FFR measurements were successfully conducted in 104 vessels, finally 98 vessels with both FFR, UFR and QFR evaluation were analyzed. Mean FFR was 0.79 ± 0.12. UFR showed a strong correlation with FFR similar to QFR (r = 0.83 vs. 0.82, p = 0.795). Diagnostic accuracy of UFR was non-inferior to QFR (94% [89%-97%] versus 90% [84%-94%], p = 0.113). Sensitivity and specificity in identifying hemodynamically significant stenosis were comparable between UFR and QFR (sensitivity: 89% [79%-96%] versus 85% [74%-92%], p = 0.453; specificity: 97% [91%-99%] versus 95% [88%-99%], p = 0.625). The area under curve for UFR was 0.95 [0.90-0.98], non-inferior to QFR (difference = 0.021, p = 0.293), and significantly higher than minimum lumen area (MLA; difference = 0.13, p < 0.001). Diagnostic accuracy of UFR and QFR was not statically different in bifurcation nor non-bifurcation lesions. CONCLUSIONS: UFR showed excellent concordance with FFR, non-inferior to QFR, superior to MLA. UFR provides a potentiality for the integration of physiological assessment and intravascular imaging in clinical practice.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Humanos , Estudos Retrospectivos , Constrição Patológica , Ultrassom , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Angiografia Coronária/métodos , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Valor Preditivo dos Testes , Índice de Gravidade de Doença
7.
Eur Radiol ; 34(4): 2608-2618, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37840099

RESUMO

OBJECTIVE: To develop a bimodal nomogram to reduce unnecessary biopsies in breast lesions with discordant ultrasound (US) and mammography (MG) Breast Imaging Reporting and Data System (BI-RADS) assessments. METHODS: This retrospective study enrolled 706 women following opportunistic screening or diagnosis with discordant US and MG BI-RADS assessments (where one assessed a lesion as BI-RADS 4 or 5, while the other assessed the same lesion as BI-RADS 0, 2, or 3) from two medical centres between June 2019 and June 2021. Univariable and multivariable logistic regression analyses were used to develop the nomogram. DeLong's and McNemar's tests were used to assess the model's performance. RESULTS: Age, MG features (margin, shape, and density in masses, suspicious calcifications, and architectural distortion), and US features (margin and shape in masses as well as calcifications) were independent risk factors for breast cancer. The nomogram obtained an area under the curve of 0.87 (95% confidence interval (CI), 0.83-0.91), 0.91 (95% CI, 0.87 - 0.96), and 0.92 (95% CI, 0.86-0.98) in the training, internal validation, and external testing samples, respectively, and demonstrated consistency in calibration curves. Coupling the nomogram with US reduced unnecessary biopsies from 74 to 44% and the missed malignancies rate from 13 to 2%. Similarly, coupling with MG reduced missed malignancies from 20 to 6%, and 63% of patients avoided unnecessary biopsies. Interobserver agreement between US and MG increased from - 0.708 (poor agreement) to 0.700 (substantial agreement) with the nomogram. CONCLUSION: When US and MG BI-RADS assessments are discordant, incorporating the nomogram may improve the diagnostic accuracy, avoid unnecessary breast biopsies, and minimise missed diagnoses. CLINICAL RELEVANCE STATEMENT: The nomogram developed in this study could be used as a computer program to assist radiologists with detecting breast cancer and ensuring more precise management and improved treatment decisions for breast lesions with discordant assessments in clinical practice. KEY POINTS: • Coupling the nomogram with US and mammography improves the detection of breast cancers without the risk of unnecessary biopsy or missed malignancies. • The nomogram increases mammography and US interobserver agreement and enhances the consistency of decision-making. • The nomogram has the potential to be a computer program to assist radiologists in identifying breast cancer and making optimal decisions.


Assuntos
Neoplasias da Mama , Nomogramas , Feminino , Humanos , Estudos Retrospectivos , Ultrassom , Mamografia/métodos , Neoplasias da Mama/patologia , Biópsia
8.
J Vis ; 23(11): 72, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37733506

RESUMO

Scleral biomechanics plays a key role in the understanding of myopia progression. In this study, we characterized the elastic properties of sclera using an air-coupled ultrasonic (ACUS) optical coherence elastography (OCE) system. New Zealand rabbit eyes (n=7) were measured (<24hr postmortem) in four scleral locations: superior/inferior temporal (ST, IT), and superior/inferior nasal (SN, IN) maintaining an intraocular pressure of 15 mmHg. Elastic waves were induced in the sclera, and wave propagation velocity and shear modulus were measured along two directions: circumferential (superior-inferior) and meridional (nasal-temporal). Wave velocity in scleral tissue ranged from 6 to 24 m/s and shear modulus from 11 to 150 kPa. Velocity was significantly higher (p<.001) in the circumferential vs. meridional directions in the following locations: ST:15.83±2.85 vs 9.43±1.68 m/s, IT:15.00±3.98 vs 8.93±1.53 m/s; SN:16.79±4.30 vs 9.27±1.47 m/s; and IN:13.92±3.85 vs 8.57±1.46 m/s. The average shear modulus in the circumferential was also significantly higher (p<.001) than in the meridional direction for all locations: 65.37±6.04 vs 22.55±1.36 kPa. These results show that the rabbit sclera is mechanically anisotropic with higher rigidity in the circumferential direction compared to the meridional direction. ACUS-OCE is a promising non-invasive method to quantify the biomechanical changes in scleral tissue for future studies involving myopia treatments.


Assuntos
Técnicas de Imagem por Elasticidade , Meridianos , Miopia , Animais , Coelhos , Ultrassom , Esclera/diagnóstico por imagem , Anisotropia , Miopia/diagnóstico por imagem
9.
Z Med Phys ; 33(3): 256-266, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37316428

RESUMO

Capacitive micromachined ultrasonic transducer (cMUT) technology has steadily advanced since its advent in the mid-1990's. Though cMUTs have not supplanted piezoelectric transducers for medical ultrasound imaging to date, researchers and engineers are continuing to improve cMUTs and leverage unique cMUT characteristics toward new applications. While not intended to be an exhaustive review of every aspect of cMUT state-of-the-art, this article provides a brief overview of cMUT benefits, challenges, and opportunities, as well as recent progress in cMUT research and translation.


Assuntos
Desenvolvimento Industrial , Ultrassom , Desenho de Equipamento , Ultrassonografia , Transdutores
10.
Sci Rep ; 13(1): 8898, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264043

RESUMO

Prevalence of liver disease is continuously increasing and nonalcoholic fatty liver disease (NAFLD) is the most common etiology. We present an approach to detect the progression of liver steatosis based on quantitative ultrasound (QUS) imaging. This study was performed on a group of 55 rats that were subjected to a control or methionine and choline deficient (MCD) diet known to induce NAFLD. Ultrasound (US) measurements were performed at 2 and 6 weeks. Thereafter, animals were humanely euthanized and livers excised for histological analysis. Relative backscatter and attenuation coefficients were simultaneously estimated from the US data and envelope signal-to-noise ratio was calculated to train a regression model for: (1) fat fraction percentage estimation and (2) performing classification according to Brunt's criteria in grades (0 <5%; 1, 5-33%; 2, >33-66%; 3, >66%) of liver steatosis. The trained regression model achieved an [Formula: see text] of 0.97 (p-value < 0.01) and a RMSE of 3.64. Moreover, the classification task reached an accuracy of 94.55%. Our results suggest that in vivo QUS is a promising noninvasive imaging modality for the early assessment of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Ultrassom , Fígado/diagnóstico por imagem , Fígado/patologia , Ultrassonografia/métodos , Colina
12.
Bioresour Technol ; 376: 128857, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36906239

RESUMO

This study aimed to pretreat the waste activated sludge (WAS) by ultrasonication in an energy efficient way by combining sodium citrate with ultrasonic pretreatment at 0.03 g/g suspended solids (SS) of dosage. The ultrasonic pretreatment was done at various (20-200 W) power levels, sludge concentration (7 to 30 g/L), sodium citrate dosages (0.01 to 0.2 g/g SS). An elevated COD solubilization of 26.07 ± 0.6 % was achieved by combined pretreatment at a treatment time of 10 min, ultrasonic power level of 160 W when compared to individual ultrasonic pretreatment (18.6 ± 0.5 %). A higher biomethane yield of 0.26 ± 0.009 L/g COD was achieved in sodium citrate combined ultrasonic pretreatment (SCUP) than ultrasonic pretreatment (UP) 0.145 ± 0.006 L/g COD. Almost 50% of the energy can be saved through SCUP when compared to UP. Future study evaluating SCUP in continuous mode anaerobic digestion is vital.


Assuntos
Biocombustíveis , Esgotos , Citrato de Sódio , Biocombustíveis/análise , Análise Custo-Benefício , Ultrassom , Anaerobiose , Eliminação de Resíduos Líquidos , Metano
13.
Transl Vis Sci Technol ; 12(2): 24, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790819

RESUMO

Purpose: The purpose of this study was to assess the performance of ultrasonic (US) vitrectomy devices by quantifying and comparing its impact on extracted vitreous properties to conventional pneumatic blade (PB) cutters using micro-extensional rheology. US vitrectomy is a new technology that offers an alternative to PB cutters used in vitreo-retinal surgeries. Methods: Thirty-six porcine vitreous samples were extracted using US and PB cutters. Each sample was kept at 4°C and tested within 24 hours postmortem and 4 hours post-vitrectomy. A recently developed micro-extensional rheology technique is used to infer the relative protein fragment size of extracted vitreous by quantifying the extensional relaxation time. Results: US-extracted vitreous exhibited extensional relaxation times orders of magnitude lower than PB-extracted vitreous (0.37 ms and 27.25 ms, respectively). Relaxation time is directly correlated to the fragment size of the collagen fibers in the vitreous. The formation of beads-on-a-string droplets within the PB samples indicates the presence of larger collagen fragments. These droplets were not seen on US samples. Conclusions: This new micro-extensional rheology technique can identify significant differences in physical properties of extracted vitreous. Long relaxation times and beads-on-a-string droplets within the PB vitreous samples indicate larger protein fragments compared to the US samples. Translational Relevance: Higher fragmentation of vitreous and lower extensional relaxation times may improve retina safety due to a reduction in vitreo-retinal traction resulting from the continuous shear action and aspiration applied by ultrasonic vitrectomy technology.


Assuntos
Vitrectomia , Corpo Vítreo , Suínos , Animais , Corpo Vítreo/diagnóstico por imagem , Corpo Vítreo/cirurgia , Corpo Vítreo/metabolismo , Ultrassom , Colágeno , Reologia
14.
J Med Econ ; 26(1): 179-188, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36646702

RESUMO

AIMS: Advanced energy devices are commonly used in electrosurgery, including ultrasonic and advanced bipolar (ABP) devices. Smoke evacuation and reusable dispersive electrodes are also utilized during electrosurgery to improve staff and patient safety. This study assessed the budget impact of adopting a portfolio of Ethicon energy devices compared to devices from other manufacturers from a Spanish hospital perspective. METHODS: The main analysis compared the Ethicon advanced energy device portfolio (ultrasonic and ABP devices) to Non-Ethicon advanced energy devices. It was assumed that 4,000 procedures using one advanced energy device each were performed annually, and the cost impact of operating room time, length of stay, and transfusions were considered. A probabilistic budget impact analysis with 10,000 iterations was conducted for generalizability to other hospitals in Spain and Europe. Secondary analysis assessed whether cost savings from the Ethicon advanced energy device portfolio could offset costs of adopting smoke evacuation and reusable dispersive electrodes (Full Ethicon energy portfolio). RESULTS: In the main analysis, the annual budget impact of introducing the Ethicon advanced energy device portfolio was cost saving in 79.8% of probabilistic iterations (mean: -€945,214; 95% credible interval [CrI]: -€3,242,710; €1,285,942) with a mean budget impact per procedure of -€236 (95% CrI: -€811; €321). In the secondary analysis, adding smoke evacuation and reusable dispersive electrodes was still cost saving in 75.3% of iterations compared to Non-Ethicon advanced energy devices (mean: -€778,208; 95% CrI: -€3,075,086; €1,464,728) with a mean budget impact per procedure of -€97 (95% CrI: -€384; €183). Savings resulted from differences in operating room time, length of hospital stay, and volume of disposable electrodes. CONCLUSIONS: Adopting Ethicon advanced energy devices demonstrated economic benefits compared to non-Ethicon devices. Introducing the advanced portfolio may improve surgical care quality and the full portfolio was cost saving while improving OR safety for staff and patients.


This study created an economic model to calculate whether using modern electrical surgical tools with features to make cutting tissue and stopping bleeding faster and easier could save Spanish hospitals money. The electrical surgery tools from one manufacturer were compared to those from various other companies. Differences in how long surgery took to perform, how long patients stayed in hospital after their surgery, and how many blood transfusions they needed were considered in the model. The model was tested 10,000 times with random changes in the costs and settings used to be surer about the range of possible results. The results showed the devices from one manufacturer could save a Spanish hospital money in almost 80% of model runs and that savings worked out to €236 per surgery. In another analysis, savings were enough to cover the cost of introducing safety devices to remove surgical smoke from the operating room and reusable patient grounding electrodes that prevent some injuries potentially caused by small sticky electrodes. In conclusion, the model showed that Spanish hospitals may be able to save money by switching to the modern electrical surgery tools from Ethicon.


Assuntos
Eletrocirurgia , Ultrassom , Humanos , Orçamentos , Hospitais , Salas Cirúrgicas
15.
PeerJ ; 11: e14546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650830

RESUMO

Background: Preoperative prediction of cervical lymph node metastasis in papillary thyroid carcinoma provided a basis for tumor staging and treatment decision. This study aimed to investigate the utility of machine learning and develop different models to preoperatively predict cervical lymph node metastasis based on ultrasonic radiomic features and clinical characteristics in papillary thyroid carcinoma nodules. Methods: Data from 400 papillary thyroid carcinoma nodules were included and divided into training and validation group. With the help of machine learning, clinical characteristics and ultrasonic radiomic features were extracted and selected using randomforest and least absolute shrinkage and selection operator regression before classified by five classifiers. Finally, 10 models were built and their area under the receiver operating characteristic curve, accuracy, sensitivity, specificity, positive predictive value and negative predictive value were measured. Results: Among the 10 models, RF-RF model revealed the highest area under curve (0.812) and accuracy (0.7542) in validation group. The top 10 variables of it included age, seven textural features, one shape feature and one first-order feature, in which eight were high-dimensional features. Conclusions: RF-RF model showed the best predictive performance for cervical lymph node metastasis. And the importance features selected by it highlighted the unique role of higher-dimensional statistical methods for radiomics analysis.


Assuntos
Neoplasias da Glândula Tireoide , Ultrassom , Humanos , Estudos Retrospectivos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem
16.
Int J Dent Hyg ; 21(3): 505-513, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36478060

RESUMO

OBJECTIVES: This study aimed to classify occupational hazards of ultrasonic scaling by factor and to identify the distribution of occupational risk levels of the study participants according to occupational hazards. In addition, the relationship between the general characteristics of dental hygienists and the occupational risk level of scaling was investigated. METHODS: This study was conducted on 237 dental hygienists. Exposure frequency and the degree of work loss were investigated on a five-point scale for each of the 15 occupational hazards of scaling. RESULTS: Among occupational hazards, the proportion of high-risk individuals for biological hazards (32.9%) was the highest. Dental clinics (33.6%) were found to have a higher proportion of high-risk individuals than dental hospitals (16.5%) (p < 0.05). The proportion of high-risk individuals was higher in the absence of an infection control coordinator (33.9%) (p < 0.05) and infection control education in the preceding 2 years (28.6%) (p < 0.05). CONCLUSION: To create a safe dental work environment, appropriate measures according to the risk level and measurement of occupational risk should be discussed.


Assuntos
Higienistas Dentários , Raspagem Dentária , Humanos , Raspagem Dentária/efeitos adversos , Higienistas Dentários/educação , Ultrassom
17.
Environ Sci Pollut Res Int ; 30(6): 14497-14517, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36152093

RESUMO

This work investigates the efficacy of α-MnO2 nanorods for persulfate-mediated degradation of bisphenol A (BPA) and methylene blue (MB), in silent and ultrasonic-assisted systems. The conversion of α-MnO2 nanoparticle flakes to nanorods occurs upon calcination at a temperature of 400 °C for 3 h under the ramping conditions. The comparative characterization of nanomaterials pre- and post-calcination reveals better physical, chemical, and thermal properties of α-MnO2 nanorods. The impact of various operational parameters such as pH, dosage of nanorods, persulfate dose, selected contaminant concentration, ultrasound frequency and power, scavengers, and landfill leachate medium on the degradation of pollutants is also assessed. The ultrasonic assistance yields higher removal for both BPA and MB than the silent system. This may be attributed to the generation of more radicals as ultrasound activates persulfate. This can be due to acoustic cavitation, which leads to better solute dissociation and excited state. The results obtained through scavenger tests reveal that both OH• and SO4•- can contribute to degradation, but the role of SO4•- is found dominant. Significant removal of BPA and MB ((BPA)silent, 87.12%; (MB)silent, 96.54%; (BPA)ultrasonic, 88.75%; (MB)ultrasonic, 93.86%)) is observed in landfill leachate medium. The degradation pathway for pollutants is also proposed. The toxicity of pollutants and their degradation intermediates are evaluated using Ecological Structure Activity Relationships (ECOSAR) program. The results indicate reduced toxicity of BPA intermediates, while most MB degradation intermediates show higher toxicity. Therefore, it can be affirmed that removing pollutants does not ensure a completely non-toxic process. However, the study proposes a comprehensive toxicity evaluation and eliminating toxic intermediates for completely harmless wastewater treatment.


Assuntos
Nanotubos , Poluentes Químicos da Água , Oxirredução , Óxidos , Azul de Metileno/química , Ultrassom , Poluentes Químicos da Água/análise , Compostos de Manganês , Compostos Benzidrílicos/química
18.
IEEE Trans Biomed Eng ; 70(4): 1310-1317, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36260593

RESUMO

OBJECTIVE: Current elastography techniques in the field of ophthalmology usually target one specific tissue, such as the cornea or the sclera. However, the eye is an inter-related organ, and some ocular diseases can alter the biomechanical properties of multiple anatomical structures. Hence, there is a need to develop an imaging tool that can non-invasively, quantitatively, and accurately characterize dynamic changes among these biomechanical properties. METHODS: A high resolution ultrasound elastography system was developed to achieve this goal. The efficacy and accuracy of the system was first validated on tissue-mimicking phantoms while mechanical testing measurements served as the gold standard. Next, an in vivo elevated intraocular pressure (IOP) model was established in rabbits to further test our system. In particular, elastography measurements were obtained at 5 IOP levels, ranging from 10 mmHg to 30 mmHg in 5 mmHg increments. Spatial-temporal maps of the multiple ocular tissues (cornea, lens, iris, optic nerve head, and peripapillary sclera) were obtained. RESULTS: The spatial-temporal maps were acquired simultaneously for the ocular tissues at the 5 different IOP levels. The statistical analysis of the elastic wave speed was presented for ocular tissues. Finally, the mapping for the elastic wave speed of each ocular component was acquired at each IOP level. CONCLUSION: Our elastography system can concurrently assess the biomechanical properties of multiple ocular structures and detect changes in biomechanical properties associated with changes in IOP. SIGNIFICANCE: This system provides a novel tool to measure and quantify the biomechanical properties of the whole eye.


Assuntos
Técnicas de Imagem por Elasticidade , Ultrassom , Animais , Coelhos , Fenômenos Biomecânicos , Som , Córnea/diagnóstico por imagem
19.
Int J Biol Macromol ; 225: 255-265, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334636

RESUMO

This study performed a comprehensive investigation of Hyperici Perforati Herba polysaccharide (HPHP) regarding the development and optimization of extraction methods, elucidation of structure and characteristics, and determination of antioxidant activities. An ultrasonic-assisted extraction method, which offered advantages in terms of the extraction yield and energy efficiency, was developed by response surface analysis. The following optimum conditions were determined: a crushing degree at 65 mesh, ultrasonic time at 50 min and temperature of 43 °C. Through enzyme-mediated deproteination via the Sevag method, activated carbon depigmentation, and DEAE-52 and Sephadex G-100 column elution, three HPHPs were obtained, and their monosaccharides mainly included mannose, galactose, glucose and arabinose. The molar weights were 8.347, 1.199 and 22.426 kDa, respectively. The HPHP structures were an amorphous aggregate of spherical-like shapes with a rough surface of pores and crevices, which presented characteristic Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectra of polysaccharides. Their main glucosidic linkage is the α-type configuration. Moreover, HPHPs exhibited strong scavenging activity for DPPH·, ABTS·+, OH· and O2·- radicals; good ferric reducing power; and effective protection against oxidative damage in human cells. Overall, the results of this work underpinned a fundamental understanding of HPHPs, thus providing a potential antioxidant for further research and development.


Assuntos
Antineoplásicos , Antioxidantes , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Ultrassom , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/farmacologia , Polissacarídeos/química
20.
Environ Sci Pollut Res Int ; 30(2): 3527-3548, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35947265

RESUMO

In first, the Ni-doped ZnO nanorods used as an appeal sonocatalyst was synthesized through co-precipitation method. Afterwards, the crystalline structure, functional groups, surface morphology, and elemental composition were characterized by a set of analysis. Removal of diazinon ((DZ) as a renowned pesticide) was investigated using sonocatalytic performance of US/Ni-doped ZnO system. In this empirical study, response surface methodology (RSM) based central composite design (CCD) was applied for optimization of operational factors. Under the optimum conditions such as initial pH = 5, initial DZ concentration = 15 mg L-1, sonocatalyst dosage = 1 g L-1, and in the presence of organic compounds (oxalic acid, humic acid, and folic acid) = 3 mg L-1, the sonocatalytic degradation of DZ after 15 min was 82.29%. The F-value (6.64) and P-value (< 0.0001) for DZ degradation in the quadratic model imply the proposed model was significant. A-factor (pH) considers as a prominent factor owing to having the highest F-value. In addition, the sonocatalytic data in this study exhibited valid fitting for the first order kinetic model (R2 > 0.98). After six consecutive cycles, the Ni-doped ZnO nanorods could be recyclable for sonocatalytic degradation of DZ. The five main compounds produced during the US/Ni-doped ZnO embracing 2-isopropyl-6-methyl-4-pyrimidinol (IMP), diethyl phosphonate, diazoxon, hydroxyldiazinon, and diazinon methyl ketone are formed in the path of DZ degradation. OFAT style also revealed 99.99% of DZ degradation with 73.26% of mineralization rate in optimum status. The Ni-doped ZnO presented agreeable sonocatalytic facility in the refinement of real water and wastewater matrix. Finally, the results of toxicity evaluation (Daphnia magna) in the sonocatalytic degradation of DZ (by US/Ni-doped ZnO system) showed that the toxicity of the DZ solution lessened under US waves (LC50 and TU 48 h equal to 36.472 and 2.741 volume percent, respectively).


Assuntos
Praguicidas , Óxido de Zinco , Diazinon , Ultrassom , Óxido de Zinco/química , Águas Residuárias
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