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1.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446780

RESUMO

Removing antibiotics from water is critical to prevent the emergence and spread of antibiotic resistance, protect ecosystems, and maintain the effectiveness of these vital medications. The combination of ozone and electrocoagulation in wastewater treatment provides enhanced removal of contaminants, improved disinfection efficiency, and increased overall treatment effectiveness. In this work, the removal of sulfamethoxazole (SMX) from an aqueous solution using an ozone-electrocoagulation (O-EC) system was optimized and modeled. The experiments were designed according to the central composite design. The parameters, including current density, reaction time, pH, and ozone dose affecting the SMX removal efficiency of the OEC system, were optimized using a response surface methodology. The results show that the removal process was accurately predicted by the quadric model. The numerical optimization results show that the optimum conditions were a current density of 33.2 A/m2, a time of 37.8 min, pH of 8.4, and an ozone dose of 0.7 g/h. Under these conditions, the removal efficiency reached 99.65%. A three-layer artificial neural network (ANN) with logsig-purelin transfer functions was used to model the removal process. The data predicted by the ANN model matched well to the experimental data. The calculation of the relative importance showed that pH was the most influential factor, followed by current density, ozone dose, and time. The kinetics of the SMX removal process followed the first-order kinetic model with a rate constant of 0.12 (min-1). The removal mechanism involves various processes such as oxidation and reduction on the surface of electrodes, the reaction between ozone and ferrous ions, degradation of SMX molecules, formation of flocs, and adsorption of species on the flocs. The results obtained in this work indicate that the O-EC system is a potential approach for the removal of antibiotics from water.


Assuntos
Ozônio , Poluentes Químicos da Água , Sulfametoxazol/química , Ozônio/química , Ecossistema , Poluentes Químicos da Água/química , Antibacterianos , Eletrocoagulação , Redes Neurais de Computação , Água
2.
Am J Otolaryngol ; 43(3): 103397, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35210111

RESUMO

PURPOSE: To evaluate the efficiency of a biodegradable gel containing hyaluronic acid and berberine hydrochloride in endoscopic sinus surgery. METHODS: Sixty-six chronic rhinosinusitis patients with or without nasal polyps who underwent bilateral endoscopic sinus surgery (ESS) were randomly received a biodegradable gel containing hyaluronic acid and berberine hydrochloride or merocel in both middle meatal spacers at the end procedure of ESS. Lund-Kennedy endoscopic score (LKES) was used to examine status of nasal cavity on preoperative day and postoperative day 1 to 7. The LKES ratio was calculated as the LKES on postoperative day divided into the LKES on preoperative day. Visual analogue score (VAS) was used to assess patient's status from the first postoperative day to the hospital discharge day. The average VAS during hospital stays was calculated by the sum of VAS in each examination day divided into the number of examined day. The LKES ratio, the average of VAS during hospital stays and length of hospitalized day of the patients were used as clinical outcome indices in early stage after surgery. A general linear model adjusted for confounding factors was used for data analysis. RESULTS: Adjusted mean of LKES ratio were lower in group used biodegrable gel of hyaruloic acid and berberin hydrochlode (study group) than those in merocele group in the postoperative day 1 to day 7. However, significant difference was found in the adjusted mean of LKES ratio on the postoperative day 2 to 6. Similarly, the adjusted mean of VAS during hospital stays and length of hospitalized day after surgery in study group were significantly decreased as compared with those in merocele group. CONCLUSIONS: Biodegradable material containing hyaluronic acid and berberine hydrochloride was more effective than merocel in length of hospital stay, post-operative symptoms, and sinus cavity's status in early stage after ESS.


Assuntos
Berberina , Pólipos Nasais , Rinite , Sinusite , Doença Crônica , Endoscopia/métodos , Humanos , Ácido Hialurônico , Pólipos Nasais/cirurgia , Estudos Prospectivos , Rinite/diagnóstico , Rinite/cirurgia , Sinusite/diagnóstico , Sinusite/cirurgia , Resultado do Tratamento
3.
J Nanosci Nanotechnol ; 18(4): 2294-2303, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442895

RESUMO

This paper presents the results of zeta potential, water contact angle, atomic force microscopy image, in vitro solubility, and content of heavy metals in polylactic acid (PLA)/chitosan (CS) nanoparticles loading nifedipine. In addition, the In Vivo test of the PLA/CS nanoparticles loading nifedipine in the mice is also one of highlights of this work. The Zeta potential result shows that the charged surface of the PLA/CS nanoparticles loading nifedipine is neutral, negative or complex depending on nifedipine content. Nifedipine plays a role in increase of hydrophobic property, swelling degree and regular surface as well as decrease of surface rough of the nanoparticles. The PLA/CS/nifedipine nanoparticles are dissolved in the solutions with pH 6.8, pH 4.5 and pH 1.2. The In Vivo test of PLA/CS nanoparticles loading nifedipine on mice was evaluated by the change in diastolic pressure, systolic pressure, arterial pressure and heart rate. The obtained results confirm that the PLA/CS nanoparticles loading nifedipine is suitable to apply in the treatment of hypertension patients lately.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Quitosana/química , Nanopartículas , Nifedipino/administração & dosagem , Poliésteres/química , Animais , Bloqueadores dos Canais de Cálcio/farmacocinética , Humanos , Camundongos , Nifedipino/farmacocinética , Polímeros
4.
Sensors (Basel) ; 15(1): 656-71, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25559000

RESUMO

In this paper, we present a pseudo optimization method for electronic nose (e-nose) data using region selection with feature feedback based on regularized linear discriminant analysis (R-LDA) to enhance the performance and cost functions of an e-nose system. To implement cost- and performance-effective e-nose systems, the number of channels, sampling time and sensing time of the e-nose must be considered. We propose a method to select both important channels and an important time-horizon by analyzing e-nose sensor data. By extending previous feature feedback results, we obtain a two-dimensional discriminant information map consisting of channels and time units by reverse mapping the feature space to the data space based on R-LDA. The discriminant information map enables optimal channels and time units to be heuristically selected to improve the performance and cost functions. The efficacy of the proposed method is demonstrated experimentally for different volatile organic compounds. In particular, our method is both cost and performance effective for the real implementation of e-nose systems.


Assuntos
Análise Discriminante , Nariz Eletrônico , Retroalimentação , Análise de Componente Principal , Reprodutibilidade dos Testes
5.
Plast Aesthet Nurs (Phila) ; 42(1): 18-26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36450070

RESUMO

Multiple symmetric lipomatosis (MSL) is a rare disease associated with metabolic disorders and alcoholism. In this report, we describe the clinical outcome and surgical protocol for eight men with Madelung collar who underwent treatment in a craniofacial and plastic surgery facility in Hanoi, Vietnam, between May 2018 and December 2020. We discuss the patients' clinical symptoms, subclinical signs, epidemiology, magnetic resonance imaging, computerized tomography, surgical protocol, complications, and postoperative indicators that we collected and evaluated. Each patient underwent surgery in two stages (i.e., in supine and prone positions). We injected a tumescent solution 10 min before the incision. Two surgeons performed each operation simultaneously. After surgery, we followed the patients for 6-27 months. All of the patients had a history of long-time alcohol abuse and had associated comorbidities that included liver disease, blood disorders, restricted neck movement, and orthopnea. We did not have to open the trachea or transfuse blood during any of the surgical procedures. Postoperatively, all patients were satisfied with their functional results and aesthetic appearance. One patient experienced a recurrence of his MSL. We believe our surgical protocol provides optimal results for patients with MSL and Madelung collar.


Assuntos
Abdominoplastia , Alcoolismo , Lipectomia , Lipomatose Simétrica Múltipla , Cirurgiões , Masculino , Humanos , Lipomatose Simétrica Múltipla/cirurgia , Contenções , Alcoolismo/complicações
6.
J Anal Methods Chem ; 2022: 7363163, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677725

RESUMO

The study aims to examine correlations between nutrition status with different factors and dental caries of preschool children in rural areas of Vietnam. A big data based on a total of 690 children (356 boys and 334 girls), aged 2-5 years, living in Van Xuan commune, were thoroughly analyzed. Oral examinations were performed by dentists with the assistance of nursery teachers and the research team. Caries was diagnosed using criteria established by the International Caries Detection and Assessment System (ICDAS). The examined children and their parents responded to questions pertaining to dental hygiene practices. The nutrition status of preschool children was determined by the World Health Organization (WHO) standards in 2006. There are factors which have effects on the malnutrition status of children in the research. The prevalence of dental caries also contributed importantly to assess children's development. In this study, the stunting groups have a higher ratio of caries compared to the others. Children's morphology and nutritional status are associated with dental caries among the preschool children in Van Xuan commune, Vinh Tuong district, Vinh Phuc province.

7.
RSC Adv ; 12(13): 7850-7863, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35424719

RESUMO

Decorating two-dimensional (2D) nanomaterials with nanoparticles provides an effective method to integrate their physicochemical properties. In this work, we present the hydrothermal growth process of 2D zinc oxide nanoplates (ZnO NPls), then silver nanoparticles (AgNPs) were uniformly distributed on the surface of ZnO NPls through the reduction procedure of silver nitrate with sodium borohydride to create a metal-semiconductor hybrid. The amount of AgNPs on the ZnO NPls' surface was carefully controlled by varying the volume of silver nitrate (AgNO3) solution. Moreover, the effect of AgNPs on the surface-enhanced Raman scattering (SERS) property of ZnO NPls was thoroughly investigated by using methylene blue (MB) as the target molecule. After calculation, the maximum enhancement factor value for 10-4 M of MB reached 6.2 × 106 for the peak at 1436 cm-1 and the limit of detection was 10-9 M. In addition, the hybrid nanosystem could distinguish MB with good reproducibility over a wide range of concentrations, from 10-9 to 10-4 M. The SERS mechanism is well elucidated based on the chemical and electromagnetic mechanisms related to the synergism of ZnO and Ag in the enhancement of Raman signal. Abundant hot spots located at the gap between adjacent separate Ag nanoparticles and ZnO nanoplates which formed a strong local electromagnetic field and electron transfer between ZnO and Ag are considered to be the key factors affecting the SERS performance of our prepared ZnO/Ag substrates. In this research, we found high sensitivity of ZnO nanoplates/Ag nanoparticles in detecting MB molecules. This unique metal-semiconductor hybrid nanosystem is advantageous for the formation of Raman signals and is thus suitable for the trace detection of methylene blue.

8.
Environ Sci Pollut Res Int ; 29(34): 52057-52069, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35257342

RESUMO

Concentrations and profiles of 17 perfluoroalkyl substances (PFAS) including 13 perfluorocarboxylic acids (PFA) and 4 perfluoroalkyl sulfonates (PFS) were determined in whole blood, muscle, and liver samples of four freshwater fish species in West Lake and Yen So Lake (Hanoi, Vietnam). Concentrations of total 17 PFAS in fish blood samples ranged from 5.2 to 29 (median 16) ng/mL. Total 17 PFAS levels in liver samples (4.5; 2.7-6.6 ng/g wet weight) were significantly higher than in muscle samples (1.0; 0.51-2.6 ng/g wet weight). More than 90% PFAS burdens in our fish samples were attributed to muscle and blood rather than liver, but contributions of individual compounds varied greatly. The most predominant substances were perfluorooctanesulfonate (PFOS) and PFA with chain lengths from C10 to C14 (i.e., PFDA, PFUnDA, PFDoDA, PFTrDA, and PFTeDA). There is no significant difference in PFAS concentrations between the studied species (i.e., bighead carp, common carp, rohu, and tilapia), but common carp showed specific PFAS profiles as compared to other species (e.g., higher proportions of PFOS and long-chain PFA such as PFTrDA, PFTeDA, and PFHxDA). Daily intake doses of PFOS and perfluorooctanoic acid (PFOA) through fish consumption were markedly lower than the US EPA reference dose of 20 ng/kg/day. Weekly intakes of the sum of PFHxS, PFOS, PFOA, and PFNA in our study were still lower than the EFSA tolerable weekly intake of 4.4 ng/kg/week.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácidos Alcanossulfônicos/análise , Animais , Peixes , Fluorocarbonos/análise , Lagos , Medição de Risco , Distribuição Tecidual , Vietnã
9.
Heliyon ; 7(8): e06832, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34401566

RESUMO

This study presents a simple, efficient, accurate method for nonlinear time-history earthquake analysis of spatial steel frames. The proposed new fiber plastic hinge method simulating only one element for each member captures the time-history dynamic behavior of steel frames as accurately as sophisticated plastic zone methods. Stability functions and the geometric stiffness matrix are employed for predicting the second-order effects that aim to minimize computational time and computer resources. Residual stresses are considered through two fiber plastic hinges by assigning initial stress values. A numerical integration procedure using Newmark integration combined with the Newton-Raphson balanced iteration algorithm is developed to find a solution to nonlinear dynamic equilibrium equations of the structural system. Shear deformation effects are also considered in the dynamic analysis. The proposed software, named Direct Advanced Analysis and Design (DAAD), is proved to be accurate and reliable as compared with the analysis results generated by expensive commercial Finite Element Analysis (FEA) software packages. The proposed DAAD program can be improved for performance-based direct design and analysis.

10.
Anim Sci J ; 91(1): e13408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578338

RESUMO

We examined the allelic expression and positioning of two pluripotency-associated genes, OCT4 and SOX2, and two housekeeping genes, ACTB and TUBA, in 4- and 8-cell porcine embryos utilizing RNA and DNA fluorescence in situ hybridization (FISH) in single blastomeres. The proportion of blastomeres expressing SOX2 bi-allelically increased from 45% at the 4-cell stage to 60% at the 8-cell stage. Moreover, in 8-cell embryos, SOX2 was expressed bi-allelically in significantly more blastomeres than was the case for OCT4, and this was associated with a tendency for SOX2 alleles to move toward the nuclear interior during 4- to 8-cell transition. However, the radial location of OCT4 alleles did not change significantly during this transition. The locations of active and inactive alleles based on DNA and RNA FISH signals were also calculated. Inactive OCT4 alleles were located in very close proximity to the nuclear membrane, whereas active OCT4 alleles were more centrally disposed in the nucleus. Nevertheless, the nuclear location of active and inactive SOX2 alleles did not change in either 4- or 8-cell blastomeres. Our RNA and DNA FISH data provide novel information on the allelic expression patterns and positioning of pluripotency-associated genes, OCT4 and SOX2, during embryonic genome activation in pigs.


Assuntos
Blastômeros/citologia , Blastômeros/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Expressão Gênica , Suínos/embriologia , Suínos/genética , Alelos , Animais , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Fertilização in vitro , Hibridização in Situ Fluorescente , Técnicas de Maturação in Vitro de Oócitos , Técnicas In Vitro , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
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