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1.
RSC Adv ; 14(29): 20466-20478, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38946772

RESUMO

In recent years, smartphones have been integrated into rapid colorimetric sensors for heavy metal ions, but challenges persist in accuracy and efficiency. Our study introduces a novel approach to utilize biogenic gold nanoparticle (AuNP) sensors in conjunction with designing a lightbox with a color reference and machine learning for detection of Fe3+ ions in water. AuNPs were synthesized using the aqueous extract of Eleutherine bulbosa leaf as reductants and stabilizing agents. Physicochemical analyses revealed diverse AuNP shapes and sizes with an average size of 19.8 nm, with a crystalline structure confirmed via SAED and XRD techniques. AuNPs exhibited high sensitivity and selectivity in detection of Fe3+ ions through UV-vis spectroscopy and smartphones, relying on nanoparticle aggregation. To enhance image quality, we developed a lightbox and implemented a reference color value for standardization, significantly improving performance of machine learning algorithms. Our method achieved approximately 6.7% higher evaluation metrics (R 2 = 0.8780) compared to non-normalized approaches (R 2 = 0.8207). This work presented a promising tool for quantitative Fe3+ ion analysis in water.

2.
Microbiology (Reading) ; 170(3)2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38568202

RESUMO

Understanding the evolution of antibiotic resistance is important for combating drug-resistant bacteria. In this work, we investigated the adaptive response of Pseudomonas aeruginosa to ciprofloxacin. Ciprofloxacin-susceptible P. aeruginosa ATCC 9027, CIP-E1 (P. aeruginosa ATCC 9027 exposed to ciprofloxacin for 14 days) and CIP-E2 (CIP-E1 cultured in antibiotic-free broth for 10 days) were compared. Phenotypic responses including cell morphology, antibiotic susceptibility, and production of pyoverdine, pyocyanin and rhamnolipid were assessed. Proteomic responses were evaluated using comparative iTRAQ labelling LC-MS/MS to identify differentially expressed proteins (DEPs). Expression of associated genes coding for notable DEPs and their related regulatory genes were checked using quantitative reverse transcriptase PCR. CIP-E1 displayed a heterogeneous morphology, featuring both filamentous cells and cells with reduced length and width. By contrast, although filaments were not present, CIP-E2 still exhibited size reduction. Considering the MIC values, ciprofloxacin-exposed strains developed resistance to fluoroquinolone antibiotics but maintained susceptibility to other antibiotic classes, except for carbapenems. Pyoverdine and pyocyanin production showed insignificant decreases, whereas there was a significant decrease in rhamnolipid production. A total of 1039 proteins were identified, of which approximately 25 % were DEPs. In general, there were more downregulated proteins than upregulated proteins. Noted changes included decreased OprD and PilP, and increased MexEF-OprN, MvaT and Vfr, as well as proteins of ribosome machinery and metabolism clusters. Gene expression analysis confirmed the proteomic data and indicated the downregulation of rpoB and rpoS. In summary, the response to CIP involved approximately a quarter of the proteome, primarily associated with ribosome machinery and metabolic processes. Potential targets for bacterial interference encompassed outer membrane proteins and global regulators, such as MvaT.


Assuntos
Ciprofloxacina , Infecções por Pseudomonas , Humanos , Ciprofloxacina/farmacologia , Pseudomonas aeruginosa/genética , Cromatografia Líquida , Proteômica , Piocianina , Espectrometria de Massas em Tandem , Antibacterianos/farmacologia
3.
BMC Psychol ; 12(1): 219, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650026

RESUMO

This study aims to move away from the cross-sectional approach related to burnout and conduct a longitudinal study to explore the factors influencing learning burnout among management students. The study primarily adopts a questionnaire survey, with students majoring in business management. Descriptive statistics and structural equation modeling (SEM) are used to analyze the data and validate the hypotheses. The findings are: (1) There is a significant negative relationship between English anxiety and self-efficacy and a significant positive relationship between past English learning performance and self-efficacy. (2) The changes in self-efficacy are negatively related to the changes in burnout, while the changes in workload are positively related to the changes in burnout. Additionally, there is a positive relationship between English anxiety and learning burnout. (3) There is a significant negative relationship between English learning performance and burnout. The direct impact of self-efficacy on English learning performance is not supported, but it has an indirect effect through the mediating role of burnout. The study proposes strategies to improve student outcomes and well-being: (1) making English courses more engaging to boost performance and confidence, reducing learning burnout; (2) encouraging and supporting students to enhance self-efficacy and motivation; (3) assigning tasks seen as useful and interesting to lessen perceived workload and emotional exhaustion; (4) and considering English anxiety in admissions to decrease learning burnout, especially as schools gain more autonomy in their policies.


Assuntos
Desempenho Acadêmico , Esgotamento Profissional , Autoeficácia , Estudantes , Humanos , Estudos Longitudinais , Masculino , Feminino , Desempenho Acadêmico/psicologia , Desempenho Acadêmico/estatística & dados numéricos , Adulto , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Esgotamento Profissional/psicologia , Adulto Jovem , Aprendizagem , Ansiedade/psicologia , Carga de Trabalho/psicologia , Inquéritos e Questionários
4.
Prog Mol Biol Transl Sci ; 204: 109-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38458735

RESUMO

Ribonucleic acids (RNAs), including the messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), play important roles in living organisms and viruses. In recent years, the RNA-based technologies including the RNAs inhibiting other RNA activities, the RNAs targeting proteins, the RNAs reprograming genetic information, and the RNAs encoding therapeutical proteins, are useful methods to apply in prophylactic and therapeutic vaccines. In this review, we summarize and highlight the current application of the RNA therapeutics, especially on mRNA vaccines which have potential for prevention and treatment against human and animal infectious diseases.


Assuntos
Doenças Transmissíveis , RNA , Animais , Humanos , RNA/metabolismo , RNA Mensageiro/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Doenças Transmissíveis/genética , Doenças Transmissíveis/terapia
5.
Int J Mol Sci ; 25(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38396817

RESUMO

Acute myeloid leukemia (AML) is an aggressive malignancy characterized by rapid growth and uncontrolled proliferation of undifferentiated myeloid cells. Metabolic reprogramming is commonly observed in the bone marrow of AML patients, as leukemia cells require increased ATP supply to support disease progression. In this study, we examined the potential role of mesothelin as a metabolic modulator in myeloid cells in AML. Mesothelin is a well-known marker of solid tumors that promotes cancer cell proliferation and survival. We initially analyzed alterations in mesothelin expression in the myeloblast subpopulations, defined as SSC-Alow/CD45dim, obtained from the bone marrow of AML patients using flow cytometry. Our results showed overexpression of mesothelin in 34.8% of AML patients. Subsequently, metabolic changes in leukemia cells were evaluated by comparing the oxygen consumption rates (OCR) of bone marrow samples derived from adult AML patients. Notably, a higher OCR was observed in the mesothelin-positive compared to the mesothelin-low and non-expressing groups. Treatment with recombinant human mesothelin protein enhanced OCR and increased the mRNA expression of glycolytic enzymes and mitochondrial complex II in KG1α AML cells. Notably, siRNA targeting mesothelin in KG1α cells led to the reduction of glycolysis-related gene expression but had no effect on the mitochondrial complex gene. The collective results demonstrate that mesothelin induces metabolic changes in leukemia cells, facilitating the acquisition of a rapid supply of ATP for proliferation in AML. Therefore, the targeting of mesothelin presents a potentially promising approach to mitigating the progression of AML through the inhibition of glycolysis and mitochondrial respiration in myeloid cells.


Assuntos
Leucemia Mieloide Aguda , Mesotelina , Adulto , Humanos , Células Precursoras de Granulócitos/metabolismo , Succinato Desidrogenase/metabolismo , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/genética , Proliferação de Células , Respiração , Glicólise , Trifosfato de Adenosina/metabolismo
6.
Heliyon ; 9(11): e22319, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38053878

RESUMO

Magnetite nanoparticles (Fe3O4 NPs) are among the most effective Fenton-Like heterogeneous catalysts for degrading environmental contaminants. However, Fe3O4 NPs aggregate easily and have poor dispersion stability because of their magnetic properties, which seriously decrease their catalytic efficiency. In this study, a novel environmentally friendly method for synthesising Fe3O4@CA was proposed. Fe3O4 NPs were immobilized on the 3D cellulose aerogels (CAs) in order to augment the degradation efficiency of p-nitrophenol (PNP) treatment and make the separation of the catalyst accessible by vacuum filtration method. Besides, CAs were fabricated from a cellulose source extracted from water hyacinth by using different cross-linking agents, such as kymene (KM) and polyvinyl alcohol-glutaraldehyde system (PVA-GA), and other drying methods, including vacuum thermal drying and freeze drying, were evaluated in the synthesis process. As-synthesized samples were analysed by various methods, including Powder X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray analysis and Brunauer-Emmett-Teller. Then, using ultraviolet-visible spectroscopy, the difference in the degradability of PNP of the obtained material samples was also investigated to determine their potential applications. Results highlighted that the Fe3O4-3@CA-KF catalyst with an Fe3O4 loading of 0.40 g/gCA used KM as a cross-linker and the freeze-drying method demonstrated the highest PNP removal efficiency (92.5 %) in all Fe3O4@CA samples with a H2O2 content of 5 g/L. The degradation kinetics and well-fitted pseudo-first-order model were investigated. Notably, after five successive PNP degradation experiments, this catalyst retained ∼80 % of the ability to degrade PNP, indicating its outstanding reusability. In environmental remediation, this study provides valuable insights into the development of simply separated and high-efficiency catalysts for heterogeneous catalytic reactions.

7.
Radiol Case Rep ; 18(11): 3884-3888, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37670912

RESUMO

Splenic ectopic pregnancy (SEP) is a rare high-mortality condition, particularly relating to life-threatening intraperitoneal bleeding due to a high risk of spontaneous rupture. Diagnosing in a timely fashion is extremely crucial and the patients could benefit from active treatment strategies and early management. In this article, we reviewed a case of 40 years-old female who complained of lower quadrant abdominal pain and amenorrhea with a history of intrauterine device (IUD) insertion for over 6 years. Elevating b-human chorionic gonadotropin (HCG) blood levels were documented, raising concern about pregnancy-related emergency conditions. Ultrasound and magnetic resonance imaging results suggested a splenic ectopic pregnancy entity with a high rupture rate. The patient subsequently underwent laparoscopic resection for splenic mass removal. Ectopic pregnancy should cautiously be excluded in all cases of abdominal pain in childbearing-age women.

8.
Cells ; 12(16)2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626859

RESUMO

Autoimmune limbic encephalitis (LE) is a rare, but devastating complication of allogeneic hematopoietic stem cell transplantation (HSCT). There is currently limited evidence describing the risk factors, laboratory features, and underlying mechanisms of this neurologic adverse event. We retrospectively reviewed available clinical, imaging, and laboratory data from adult patients with hematological malignancies who underwent haploidentical HSCT with post-transplant cyclophosphamide (PTCy) at Chungnam National University Hospital from June 2016 to May 2020. Patients who developed LE were compared to those who did not based on clinical assessment, serum inflammatory biomarkers, and reconstitution of various T cell populations. Of 35 patients, 4 developed LE. There were no differences in patient demographics, donor demographics, or treatment conditions between patients that did and did not develop LE. Overall, patients with LE had worse clinical outcomes and overall survival than those without. In addition, they tended to have higher markers of systemic inflammation in the early post-transplant period, including fever, C-reactive protein (CRP), and cytokines. Remarkably, baseline interleukin-6 levels before HSCT were found to be higher in patients who developed LE than those who did not. In addition, analysis of T cell subsets showed impaired expansion of CD25+FOXP3+ regulatory T (Treg) cells in LE compared to non-LE patients despite appropriate reconstitution of the total CD4+ T cell population. Patients that developed LE within the first 30 days of HSCT were likely to have high serum IL-6 among other inflammatory cytokines coupled with suppression of regulatory T cell differentiation. Further work is needed on the mechanisms underlying impaired Treg expansion following HSCT and potential therapies.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Estudos Retrospectivos , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ciclofosfamida/efeitos adversos , Citocinas , Interleucina-6
9.
Environ Sci Pollut Res Int ; 30(29): 74340-74357, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37204580

RESUMO

Soil salinization is considered one of the disasters that have significant effects on agricultural activities in many parts of the world, particularly in the context of climate change and sea level rise. This problem has become increasingly essential and severe in the Mekong River Delta of Vietnam. Therefore, soil salinity monitoring and assessment are critical to building appropriate strategies to develop agricultural activities. This study aims to develop a low-cost method based on machine learning and remote sensing to map soil salinity in Ben Tre province, which is located in Vietnam's Mekong River Delta. This objective was achieved by using six machine learning algorithms, including Xgboost (XGR), sparrow search algorithm (SSA), bird swarm algorithm (BSA), moth search algorithm (MSA), Harris hawk optimization (HHO), grasshopper optimization algorithm (GOA), particle swarm optimization algorithm (PSO), and 43 factors extracted from remote sensing images. Various indices were used, namely, root mean square error (RMSE), mean absolute error (MAE), and the coefficient of determination (R2) to estimate the efficiency of the prediction models. The results show that six optimization algorithms successfully improved XGR model performance with an R2 value of more than 0.98. Among the proposed models, the XGR-HHO model was better than the other models with a value of R2 of 0.99 and a value of RMSE of 0.051, by XGR-GOA (R2 = 0.931, RMSE = 0.055), XGR-MSA (R2 = 0.928, RMSE = 0.06), XGR-BSA (R2 = 0.926, RMSE = 0.062), XGR-SSA (R2 = 0.917, 0.07), XGR-PSO (R2 = 0.916, RMSE = 0.08), XGR (R2 = 0.867, RMSE = 0.1), CatBoost (R2 = 0.78, RMSE = 0.12), and RF (R2 = 0.75, RMSE = 0.19), respectively. These proposed models have surpassed the reference models (CatBoost and random forest). The results indicated that the soils in the eastern areas of Ben Tre province are more saline than in the western areas. The results of this study highlighted the effectiveness of using hybrid machine learning and remote sensing in soil salinity monitoring. The finding of this study provides essential tools to support farmers and policymakers in selecting appropriate crop types in the context of climate change to ensure food security.


Assuntos
Gafanhotos , Solo , Animais , Tecnologia de Sensoriamento Remoto , Rios , Salinidade , Vietnã , Aprendizado de Máquina
10.
ACS Omega ; 7(41): 36623-36633, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36278060

RESUMO

Hydroxyapatite (HA) derived from salmon bone byproducts is used as a green support for the nanostructured nickel catalysts applied in the methanation of carbon dioxide (CO2). Undoped nickel catalysts and various ceria-doped nickel supported on hydroxyapatite (HA) were prepared by coimpregnation. Characteristics of the as-prepared catalysts were investigated by the various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), hydrogen temperature-programmed reduction (H2-TPR), carbon dioxide temperature-programmed desorption (CO2-TPD), and energy-dispersive X-ray spectroscopy (EDX). The catalyst activity was assessed throughout CO2 methanation in the low-temperature range of 225-350 °C with the molar ratio of H2/CO2 = 4/1. The function of HA and ceria provided a high dispersity of nickel particles over the catalyst surface with the size range of 24.5-25.8 nm, leading to improvement in the reduction and CO2 adsorption capacity of the catalysts as well as enhancing the catalytic efficiency in CO2 methanation. The 10Ni/HA catalyst reduced at suitable conditions of 400 °C for 2 h showed the highest catalytic performance among the tested catalysts. CO2 conversion and CH4 selectivity reached 76.6 and 100% at a reaction temperature of 350 °C, respectively. The results show that the Ni/HA sample doped with 6.0 wt % ceria was the best, with the CO2 conversion and the CH4 selectivity reaching 92.5% and 100%, respectively, at a reaction temperature of 325 °C.

11.
Nutrients ; 14(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35684042

RESUMO

Fucoidan, a sulfated polysaccharide extracted from brown seaweed, has been proposed to effectively treat and prevent various viral infections. However, the mechanisms behind its antiviral activity are not completely understood. We investigate here the global transcriptional changes in bone marrow-derived dendritic cells (BMDCs) using RNA-Seq technology. Through both analysis of differentially expressed genes (DEG) and gene set enrichment analysis (GSEA), we found that fucoidan-treated BMDCs were enriched in virus-specific response pathways, including that of SARS-CoV-2, as well as pathways associated with nucleic acid-sensing receptors (RLR, TLR, NLR, STING), and type I interferon (IFN) production. We show that these transcriptome changes are driven by well-known regulators of the inflammatory response against viruses, including IRF, NF-κB, and STAT family transcription factors. Furthermore, 435 of the 950 upregulated DEGs are classified as type I IFN-stimulated genes (ISGs). Flow cytometric analysis additionally showed that fucoidan increased MHCII, CD80, and CD40 surface markers in BMDCs, indicative of greater antigen presentation and co-stimulation functionality. Our current study suggests that fucoidan transcriptionally activates PRR signaling, type I IFN production and signaling, ISGs production, and DC maturation, highlighting a potential mechanism of fucoidan-induced antiviral activity.


Assuntos
COVID-19 , Células Dendríticas , Antivirais/metabolismo , Antivirais/farmacologia , Humanos , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , SARS-CoV-2
12.
Adv Sci (Weinh) ; 9(9): e2105248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35332701

RESUMO

To date, a number of studies have reported the use of vibrations coupled to ferroelectric materials for water splitting. However, producing a stable particle suspension for high efficiency and long-term stability remains a challenge. Here, the first report of the production of a nanofluidic BaTiO3 suspension containing a mixture of cubic and tetragonal phases that splits water under ultrasound is provided. The BaTiO3 particle size reduces from approximately 400 nm to approximately 150 nm during the application of ultrasound and the fine-scale nature of the particulates leads to the formation of a stable nanofluid consisting of BaTiO3 particles suspended as a nanofluid. Long-term testing demonstrates repeatable H2 evolution over 4 days with a continuous 24 h period of stable catalysis. A maximum rate of H2 evolution is found to be 270 mmol h-1 g-1 for a loading of 5 mg l-1 of BaTiO3 in 10% MeOH/H2 O. This work indicates the potential of harnessing vibrations for water splitting in functional materials and is the first demonstration of exploiting a ferroelectric nanofluid for stable water splitting, which leads to the highest efficiency of piezoelectrically driven water splitting reported to date.

13.
Environ Sci Pollut Res Int ; 29(28): 42074-42089, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35129745

RESUMO

Single-use plastic waste is gradually considered a potential material for circular economy. Ion exchange resin obtained from polystyrene waste by sulfonating with H2SO4 was used for heavy metal removal from electroplating wastewater. Batch mode experiments of Cu2+, Zn2+, and Cd2+ were carried out to determine effect of pH, initial concentration, equilibrium time, and the isotherm and kinetic parameters; the stability of the resin in continuous operation was then evaluated. Finally, the longevity of the resin after being exhausted was explored. The results indicated that at pH 6, a pseudo-second-order kinetic model was applicable to describe adsorption of studied heavy metals by sulfonated polystyrene with adsorption capacities of 7.48 mg Cu2+/g, 7.23 mg Zn2+/g, and 6.50 mg Cd2+/g, respectively. Moreover, the ion exchange process between sulfonated polystyrene resin and Cu2+, Zn2+, Cd2+ ions followed the Langmuir isotherm adsorption model with R2 higher than 96%. The continuous fixed-bed column in conditions of a sulfonated polystyrene mass of 500 g, and a flow rate of 2.2 L/h was investigated for an influent solution with known initial concentration of 20 mg/L. Thomas and Yoon-Nelson models were tested with regression analysis. When being exhausted, the sulfonated polystyrene was regenerated by NaCl in 10 min with ratio 5 mL of NaCl 2 M per 1 g saturated resins. After 4 times regeneration, the heavy metal removal efficiency of sulfonated polystyrene was reduced to 50%. These aforementioned results can figure out that by sulfonating polystyrene waste to synthesize ion exchanging materials, this method is technically efficient and environmentally friendly to achieve sustainability.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Cádmio/análise , Concentração de Íons de Hidrogênio , Cinética , Metais Pesados/análise , Plásticos , Poliestirenos/análise , Cloreto de Sódio , Águas Residuárias/análise , Poluentes Químicos da Água/análise
14.
BMJ Open ; 11(10): e053343, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598989

RESUMO

OBJECTIVES: To investigate the feasibility of establishing hospital-based antimicrobial stewardship (AMS) programmes comprising action-planning, educational interventions and data feedback in two provincial-level hospitals in Viet Nam. DESIGN AND SETTING: This was an implementation research using participatory action process and existing resources from the Duke Antimicrobial Stewardship Outreach Network with local adjustments. A national stakeholder meeting and Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis were conducted to identify gaps and potential interventions. PARTICIPANTS: Hospital AMS staff implemented activities throughout the study phases. Routinely collected patient data were analysed to support planning, implementation and evaluation. INTERVENTIONS: Hospitals were considered as a complex adaptive system and leveraged their unique characteristics and interconnections to develop 1-year plans containing core interventions (data use, educational training, prospective audit with feedback (PAF) and evaluations). OUTCOME MEASURES: We assessed feasibility using outputs from stakeholder meeting, SWOT analysis, baseline data, planning process and implementation. RESULTS: The stakeholder meeting identified three gaps for AMS at national level: supportive policies, AMS training and core competencies and collaboration. At the hospitals, AMS programmes took 1 year for planning due to lack of hospital-specific procedures and relevant staff competencies. Baseline data (January-December 2019) showed variations in antibiotic consumption: 951 days of therapy (DOT) per 1000 days present in the control and 496 in the intervention wards in hospital 1, and 737 and 714 in hospital 2, respectively. During 1-year implementation, clinical pharmacists audited 1890 antibiotic prescriptions in hospital 1 (June 2020-May 2021) and 1628 in hospital 2 (July 2020-July 2021), and will continue PAF in their daily work. CONCLUSION: Our data confirmed the need to contextualise AMS programmes in low-income and middle-income countries (LMICs) and demonstrated the usefulness of implementation research design in assessing programme feasibility. Developing staff competencies, using local data to stimulate actions and integrating programme activities in routine hospital work are key to success in LMICs.


Assuntos
Gestão de Antimicrobianos , Estudos de Viabilidade , Hospitais , Humanos , Farmacêuticos , Vietnã
15.
J Hazard Mater ; 416: 126123, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492917

RESUMO

Toxicity biosensors have recently gained significant attention due to their potential use in online monitoring. However, the effects of toxicants and the influence of dose, exposure time, and type and concentration of respiration substrate (RS) on the performance of a bioreactor are species-specific. Although these factors need to be investigated case-by-case as they can lead either to damage or self-repair of the affected microorganisms, they have seldom been considered in previous studies. Therefore, this work examined, for the first time, the effects of resting time and RS concentration on the performance of the biosensing system for toxicity of Cr6+ in water. In addition, it is also the first time that a novel non-contact fluid delivery system was applied to a toxicity biosensing system to prevent unstable responses. By choosing the best RS concentration and balancing the resting and exposure times, the proposed procedure exhibits promising results in terms of minimum detectable concentration (MDC), limit of detection (LOD), detection range, linearity, sensitivity, reproducibility and accuracy. The recovery time was only a few hours and the coefficients of variation of inhibition and recovery were only 12% and 9.6%, respectively, during six times reuse over one month of storage.


Assuntos
Técnicas Biossensoriais , Metais Pesados , Intoxicação por Metais Pesados , Humanos , Metais Pesados/toxicidade , Reprodutibilidade dos Testes , Água
16.
Heliyon ; 7(5): e07092, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34136684

RESUMO

Electroplating sludge consists of various heavy metal oxides, which may be utilized as adsorbent to remove Cu (II) present in aqueous environment. This study evaluated the adsorption performance of calcinated electroplating sludge. The adsorption isotherm based on Langmuir equation proved that calcinated electroplating sludge had a higher adsorption performance than raw electroplating sludge, with maximum adsorption capacity 92 mg/g and 76.34 mg/g, respectively. Findings of the conducted kinetic study revealed that both surface adsorption and intra-particular diffusion were involved during the adsorption process. Moreover, the comparison between the experimental and calculated data of equilibrium adsorption capacity demonstrated that the pseudo second-order kinetic equation fitted well with 38.31 mg/g of calcinated sludge and 33.66 mg/g of raw sludge, approximate to real-world data. Furthermore, adsorption mechanism research demonstrated that while OH group plays a vital role in raw sample, Ca2+, in addition to OH group, was involved in ion exchange in calcinated sample.

17.
Environ Sci Pollut Res Int ; 28(10): 11869-11881, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31953762

RESUMO

In this study, different pretreatment strategies of sugarcane bagasse prior to citric acid modification were investigated in terms of Pb2+ adsorption capacity. Pretreatment strategies included the use of NaOH, HCl, and C2H5OH in various concentrations. In order to fundamentally understand how these pretreatment methods affect the modification of sugarcane bagasse by citric acid as well as the Pb2+ adsorption capacity of sugarcane bagasse, three main components of sugarcane bagasse namely cellulose, hemicellulose, and lignin were isolated and esterified by citric acid under the same conditions. ATR-FTIR, XPS, SEM, and an analysis of the number of carboxylic acid groups were used to investigate the physicochemical and chemical properties of the materials. These three components were proved to participate in adsorption and induce the esterification with citric acid. Hence, pretreatment with ethanol and 0.01 M NaOH which could retain cellulose, hemicellulose, and lignin in sugarcane bagasse achieved a high Pb2+ adsorption capacity, i.e., 122.4 and 97 mg/g after the esterification with citric acid. In contrast, pretreatment with 0.5 M NaOH and 0.1 M HCl removed lignin and hemicellulose, leading to the lowest value of approximately 45 mg/g for citric acid esterified-pretreated sugarcane bagasse. XPS analysis and number of carboxylic group measurement confirmed the esterification between bagasse and citric acid. To understand the adsorption mechanism of adsorbent, two kinetic models including pseudo-first-order model and pseudo-second-order model were applied. The experimental data were well described by the pseudo-second-order model. The adsorption isotherm data were fitted Langmuir and Freundlich.


Assuntos
Saccharum , Poluentes Químicos da Água , Adsorção , Celulose , Ácido Cítrico , Esterificação , Chumbo
18.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-899288

RESUMO

Purpose@#Simulation teaching refers to the replication of real-life scenarios, enabling students to practice nursing skills and learn actively in a safe environment. It also helps students control their anxiety and fears when caring for real patients. This study investigated the relationships of Vietnamese nursing students’ self-confidence in clinical practice with their satisfaction and self-confidence in simulation-based practice. @*Methods@#This cross-sectional descriptive study included 182 nursing students. The data collection included 2 separate stages with 2 main questionnaires. The Student Satisfaction and Self‐Confidence in Learning Scale was used to measure students’ satisfaction and self‐confidence after learning in the simulation room. The Confidence Scale was used to measure students’ self-confidence when first performing techniques on actual patients. Data were analyzed by descriptive and Pearson correlation statistics. @*Results@#Students’ satisfaction and self-confidence during the simulation course were quite high (mean±standard deviation [SD], 4.06±0.48 and 4.11±0.46 out of 5.0, respectively). In contrast, their confidence when first practicing on a patient was moderate (mean±SD, 3.19±0.62 out of 5.0). Students’ satisfaction showed moderate and weak positive correlations with self-confidence in pre-clinical practice and in clinical practice (r=0.33, P<0.001 and r=0.26, P<0.001, respectively). @*Conclusion@#Simulation has become an effective teaching strategy that can help nursing students be well-prepared for clinical placements in Vietnam. An effective nursing education strategy is needed to enhance the satisfaction and self-confidence of nursing students in simulation and then in clinical practice to help achieve professional engagement and development.

19.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-891584

RESUMO

Purpose@#Simulation teaching refers to the replication of real-life scenarios, enabling students to practice nursing skills and learn actively in a safe environment. It also helps students control their anxiety and fears when caring for real patients. This study investigated the relationships of Vietnamese nursing students’ self-confidence in clinical practice with their satisfaction and self-confidence in simulation-based practice. @*Methods@#This cross-sectional descriptive study included 182 nursing students. The data collection included 2 separate stages with 2 main questionnaires. The Student Satisfaction and Self‐Confidence in Learning Scale was used to measure students’ satisfaction and self‐confidence after learning in the simulation room. The Confidence Scale was used to measure students’ self-confidence when first performing techniques on actual patients. Data were analyzed by descriptive and Pearson correlation statistics. @*Results@#Students’ satisfaction and self-confidence during the simulation course were quite high (mean±standard deviation [SD], 4.06±0.48 and 4.11±0.46 out of 5.0, respectively). In contrast, their confidence when first practicing on a patient was moderate (mean±SD, 3.19±0.62 out of 5.0). Students’ satisfaction showed moderate and weak positive correlations with self-confidence in pre-clinical practice and in clinical practice (r=0.33, P<0.001 and r=0.26, P<0.001, respectively). @*Conclusion@#Simulation has become an effective teaching strategy that can help nursing students be well-prepared for clinical placements in Vietnam. An effective nursing education strategy is needed to enhance the satisfaction and self-confidence of nursing students in simulation and then in clinical practice to help achieve professional engagement and development.

20.
Environ Sci Pollut Res Int ; 27(16): 20554-20564, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32274695

RESUMO

A simple approach was developed for the rapid and accurate estimation of 5-day biochemical oxygen demand (BOD5) in food processing wastewater. Immobilization of the natural microbial consortium that was collected from an aerobic compartment of a food processing wastewater treatment plant was simply performed by adhesion using a low-cost porous carrier. Pseudomonas aeruginosa, Bacillus cereus, and Streptomyces, whose salt-tolerance and ability to break down organic compounds have been widely reported, were found to be predominant. These microorganisms may cause an enhancement of the bioreactor response in the presence of sodium chloride. Consequently, a modified glucose-glutamic acid (GGA) calibration standard was proposed in which an appropriate amount of NaCl was added; this solution was found to be more effective in terms of accuracy and practicality than both conventional GGA and the synthetic wastewater recipe from the Organisation for Economic Cooperation and Development (OECD). The calibrated self-built packed-bed bioreactor exhibited good precision of 3% or less in predicting BOD5 in influent, which is similar to the performance of the most common commercial biochemical oxygen demand (BOD) bioreactors. There was a statistical agreement between the results obtained from this rapid BOD biosensor and the conventional methods, even when testing treated wastewater samples.


Assuntos
Técnicas Biossensoriais , Águas Residuárias/análise , Reatores Biológicos , Manipulação de Alimentos , Oxigênio/análise
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