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1.
Data Brief ; 49: 109451, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37577742

RESUMO

This dataset provides insightful data on the reality of the new national curriculum implementation from primary and secondary school teachers' perspectives. The dataset addresses four main aspects of the new curriculum implementation from teachers' perspectives: (a) teachers' capacity in implementing the new curriculum, (b) teaching conditions in implementing the new curriculum, (c) challenges for teachers in implementing the new curriculum, and (d) teachers' desires to implement the new national curriculum successfully. The survey tools used to collect the data were developed based on a literature review of implementing a new curriculum from teachers' assessment. The survey was conducted online via Google Forms from November to December 2022, with 29,026 primary and secondary school teachers in five provinces of Vietnam participating. The dataset is expected to benefit policymakers and educational administrators by providing information on key areas where teachers require support and training to improve the implementation of the new curriculum. Additionally, the dataset contributes to developing evidence-based policies and interventions to support teachers in implementing the new curriculum. Educational managers and researchers can benefit from this dataset by gaining insights and preparing adequately for implementing new curriculum or developing plans to improve curriculum development. Overall, this dataset provides valuable information for improving the effectiveness of implementing the new national curriculum.

2.
Data Brief ; 45: 108662, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36267116

RESUMO

This dataset provides an insight into the reality and experiences of online learning as perceived by secondary school students in Vietnam during COVID-related school closures. The dataset addresses four main aspects of online learning, namely (a) students' access to learning devices, (b) their digital skill readiness, (c) their experience with online learning and assessment activities, and (d) their overall evaluation of the effectiveness of online learning. The survey was administered online via Google Form from September to December 2021 with responses received from 5,327 secondary school students in 5 provinces of Vietnam. The dataset is expected to benefit local educators, administrators, and teachers who are interested in COVID educational practices and pedagogical interventions. The dataset can also benefit international researchers who wish to conduct comparative studies on student online learning or who wish to seek further insight into the responsiveness of an educational system to pandemic situations.

3.
J Anal Methods Chem ; 2021: 6670913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763287

RESUMO

In this work, an effective nanocomposite-based adsorbent directed to adsorb cobalt (Co2+) ion was successfully synthesized from graphene oxide (GO), polyvinyl alcohol (PVA), and magnetite (Fe3O4) nanoparticles via a coprecipitation technique. The synthesized GO/PVA/Fe3O4 nanocomposite was applied for Co2+ ion removal with the optimized working conditions including 100 min of contact time, 0.01 g of adsorbent dosage, pH of 5.2, and 50°C of temperature. The investigation of adsorption kinetics showed that the adsorption of Co2+ ion onto the GO/PVA/Fe3O4 nanocomposite followed the pseudo-second-order kinetic model with the rate constant k2 being 0.0026 (g mg-1·min-1). The Langmuir model is suitable to describe the adsorption of Co2+ ion onto the GO/PVA/Fe3O4 nanocomposite with the maximum sorption capacity (q max) reaching 373.37 mg·g-1. The obtained results also indicated that the GO/PVA/Fe3O4 nanocomposite can adsorb/regenerate for at least 5 cycles with a little reduction in removal efficiency. Therefore, we believe that the GO/PVA/Fe3O4 nanocomposite could be used as a potential adsorbent for heavy metal treatment in terms of high adsorption capacity, fast adsorption rate, and recyclability.

4.
RSC Adv ; 11(32): 19470-19481, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35479256

RESUMO

A novel nanostructured electrode material based on electrochemically reduced graphene oxide/polyaniline nanowires/silver nanoflowers (ERGO/PANi NWs/AgNFs) was fabricated site-specifically onto a Pt microelectrode (0.80 mm2 area) using a three-step electrochemical procedure: electrosynthesis of ERGO, electropolymerization of PANi NWs, and electrodeposition of AgNFs. Synergistic and complementary properties of ERGO, PANi NWs and AgNFs, including high electrochemical activity, large surface area, and high biocompatibility, were obtained. Besides, the electrosynthesis method allowed the direct formation of the desired nanomaterial onto the Pt microelectrode, so the adhesion between the sandwich-structured nanocomposite and the electrode surface was also improved. The optimized ERGO/PANi NWs/AgNFs nanocomposite was used for the first time to develop an electrochemical DNA sensor. As a result, the DNA probe immobilization was facilitated and the electrochemical signals of the DNA sensor were enhanced. The detection limit of the DNA sensor was 2.70 × 10-15 M. Moreover, potential miniaturization for fabrication of a lab-on-a-chip system, direct detection, high sensitivity, and good specificity are the advantages of the fabricated DNA sensor.

5.
Pestic Biochem Physiol ; 155: 51-57, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30857627

RESUMO

Two mutations Leu498 and Glu425 in the PDS gene were identified as the main cause conferring resistance to diflufenican and picolinafen in two oriental mustard populations P3 and P40. As mutations are suspected to affect fitness, this study was designed to test this hypothesis using the F2 of two crosses P3.2 (P3♂ × S♀) and P40.5 (P40♂ × S♀) of oriental mustard. The F2 plants, which segregated for target-site point mutations of PDS gene (Leu498 and Glu425) grown in monoculture and under competition with wheat in pot-trials and evaluated for growth and fecundity. All F2 individuals were genotyped by using Cleaved Amplified Polymorphic Sequence (CAPS) technique. Regression analysis showed no fitness cost in the resistant plants because no significant difference was identified in seed and biomass production within RR, RS and SS individuals. The absence of measurable negative effects on fitness associated mutations suggests that the frequency of the PDS resistance alleles will not decline in the absence of selection pressure of PDS-inhibitors.


Assuntos
Herbicidas/farmacologia , Mostardeira/efeitos dos fármacos , Mostardeira/metabolismo , Niacinamida/análogos & derivados , Oxirredutases/genética , Resistência a Herbicidas , Mostardeira/genética , Mutação/genética , Niacinamida/farmacologia , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Pest Manag Sci ; 74(6): 1279-1285, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29330913

RESUMO

BACKGROUND: An oriental mustard population (P3) collected near Quambatook, Victoria was identified as being resistant to diflufenican by screening with the field rate (200 g a.i. ha-1 ) of the herbicide. The mechanism(s) of diflufenican resistance and its inheritance in this population were therefore investigated. RESULTS: Dose-response experiments confirmed that population P3 was 140-fold more resistant to diflufenican than susceptible populations, as determined by the comparison of 50% lethal (LD50 ) values. The phytoene desaturase (PDS) gene from five individuals each of the S1 [susceptible (S)] and P3 [resistant (R)] populations was sequenced, and a substitution of valine for leucine at position 526 (Leu-526-Val) was detected in all five individuals of P3, but not in the S1 population. Inheritance studies showed that diflufenican resistance is encoded in the nuclear genome and is dominant, as the response to diflufenican at 200 g a.i. ha-1 of F1 families was equivalent to that of the resistant biotype. The segregation of F2 phenotypes fitted a 3:1 inheritance model. Segregation of 42 F2 individuals by genotype sequencing fitted a 1:2:1 (ss:Rs:RR) ratio. CONCLUSION: Resistance to diflufenican in oriental mustard is conferred by the Leu-526-Val mutation in the PDS gene. Inheritance of resistance is managed by a single gene with high levels of dominance. © 2018 Society of Chemical Industry.


Assuntos
Brassicaceae/genética , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Hereditariedade , Niacinamida/análogos & derivados , Oxirredutases/genética , Sequência de Aminoácidos , Sequência de Bases , Brassicaceae/efeitos dos fármacos , Niacinamida/farmacologia , Oxirredutases/química , Oxirredutases/metabolismo , Alinhamento de Sequência , Vitória
7.
Pest Manag Sci ; 74(6): 1524-1532, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29286550

RESUMO

BACKGROUND: Two oriental mustard populations (P2 and P13) collected from Port Broughton, South Australia were identified as resistant to 2,4-D. The level of resistance, mechanism and the mode of inheritance for 2,4-D resistance in these populations were investigated. RESULTS: Populations P2 and P13 were confirmed to be resistant to 2,4-D at the field rate (600 g a.e. ha-1 ). P2 and P13 were 81- and 67-fold more resistant than the susceptible populations (S1 and S2) at the dose required for 50% mortality (LD50 ), respectively. No predicted amino acid modification was detected in sequences of potential target-site genes (ABP, TIR1 and AFB5). Resistant populations had reduced 2,4-D translocation compared with the susceptible populations, with 77% of [14 C]2,4-D retained in the treated leaf versus 32% at 72 h after treatment. Resistance to 2,4-D is encoded on the nuclear genome and is dominant, as the response to 2,4-D of all F2 individuals were similar to the resistant biotypes. The segregation of F2 phenotypes fitted a 3: 1 (R: S) inheritance model. CONCLUSION: Resistance to 2,4-D in oriental mustard is likely due to reduced translocation of 2,4-D out of the treated leaf. Inheritance of 2,4-D resistance is conferred by a single gene with a high level of dominance. © 2017 Society of Chemical Industry.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Brassicaceae/efeitos dos fármacos , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Brassicaceae/genética , Hereditariedade , Mutação , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Austrália do Sul
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