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1.
Nature ; 573(7774): 364-369, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31391586

RESUMO

A global priority for the behavioural sciences is to develop cost-effective, scalable interventions that could improve the academic outcomes of adolescents at a population level, but no such interventions have so far been evaluated in a population-generalizable sample. Here we show that a short (less than one hour), online growth mindset intervention-which teaches that intellectual abilities can be developed-improved grades among lower-achieving students and increased overall enrolment to advanced mathematics courses in a nationally representative sample of students in secondary education in the United States. Notably, the study identified school contexts that sustained the effects of the growth mindset intervention: the intervention changed grades when peer norms aligned with the messages of the intervention. Confidence in the conclusions of this study comes from independent data collection and processing, pre-registration of analyses, and corroboration of results by a blinded Bayesian analysis.


Assuntos
Sucesso Acadêmico , Estudantes/psicologia , Adolescente , Humanos , Sistemas de Apoio Psicossocial , Reino Unido
2.
J Phys Chem A ; 128(18): 3587-3595, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38640443

RESUMO

The metal-ligand charge transfer (3MLCT) and phosphorescence-quenching metal-centered (3MC) states of the helicate and mesocate diastereoisomers of a double-stranded dinuclear polypyridylruthenium(II) complex have been investigated using ultrafast transient absorption spectroscopy. At 294 K, transient signals of the helicate decayed significantly slower than those of the mesocate, whereas at 77 K, no clear contrast in kinetics was observed. Contributions to excited-state decay from high-lying 3MLCT states were identified at both temperatures. Spectroscopic data (294 K) suggest that the 3MC state of the helicate lies above the 3MLCT and that the reverse is true for the mesocate; this was further validated by density functional theory calculations. The stabilization of the 3MC state relative to the 3MLCT state in the mesocate was explained by a reduction in ligand field strength due to distortion near the ligand bridge, which causes further deviation from octahedral geometry compared to the helicate. This work illustrates how minor structural differences can significantly influence excited state dynamics.

3.
J Am Chem Soc ; 145(37): 20365-20374, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37671920

RESUMO

This study reports the successful development of a sustainable synthesis protocol for a phase-pure metal azolate framework (MAF-6) and its application in enzyme immobilization. An esterase@MAF-6 biocomposite was synthesized, and its catalytic performance was compared with that of esterase@ZIF-8 and esterase@ZIF-90 in transesterification reactions. Esterase@MAF-6, with its large pore aperture, showed superior enzymatic performance compared to esterase@ZIF-8 and esterase@ZIF-90 in catalyzing transesterification reactions using both n-propanol and benzyl alcohol as reactants. The hydrophobic nature of the MAF-6 platform was shown to activate the immobilized esterase into its open-lid conformation, which exhibited a 1.5- and 4-times enzymatic activity as compared to free esterase in catalyzing transesterification reaction using n-propanol and benzyl alcohol, respectively. The present work offers insights into the potential of MAF-6 as a promising matrix for enzyme immobilization and highlights the need to explore MOF matrices with expanded pore apertures to broaden their practical applications in biocatalysis.


Assuntos
1-Propanol , Carboxilesterase , Esterases , Álcool Benzílico
4.
J Adv Nurs ; 77(3): 1490-1500, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33326632

RESUMO

AIMS: To investigate the energy and protein adequacy of meals and dietary intake of older psychiatric inpatients and describe patient and mealtime factors potentially influencing intake. DESIGN: Multiple case studies. METHODS: Psychiatric inpatients aged 65 years and older, admitted to a single mental health ward during the 6-week study period (April-May 2019) were eligible for inclusion. Dietary intake was observed for two consecutive days each week (minimum four observation days). Visual plate waste methods were used to estimate patients' dietary intake at mealtimes, with energy and protein intake calculated using known food composition data and compared with estimated requirements. Medical records were reviewed weekly to collect information on potential factors related to intake and mealtime care. Data from all sources were first summarized in a case record for within-case analysis using descriptive statistics, followed by cross-case analysis. RESULTS: Eight participants (five men, age 67-90 years, two underweight and one overweight, and four requiring some mealtime assistance) had 5-12 days of observation data recorded. Three met their estimated daily energy and protein requirements throughout the study period, while the remaining five participants did not. The main barriers identified as contributing to insufficient energy and protein intake were as follows: missing meals (asleep and treatment); inadequate food provided (insufficiency of the standard hospital menu); and need for increased mealtime assistance. CONCLUSION: Poor dietary intake may be common among older psychiatric patients, suggesting that they may also need nursing and multidisciplinary nutrition care interventions shown to effectively prevent and treat malnutrition in other older inpatient groups. IMPACT: Older psychiatric patients experience similar nutrition and mealtime issues to other older inpatients. This study highlights the need for nurses and the multidisciplinary team to ensure patients order and receive adequate food, especially when they miss meals and that they receive proactive mealtime assistance.


Assuntos
Hospitais Psiquiátricos , Desnutrição , Idoso , Idoso de 80 Anos ou mais , Ingestão de Alimentos , Ingestão de Energia , Humanos , Masculino , Refeições , Estado Nutricional
5.
J Educ Psychol ; 108(3): 374-391, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27524832

RESUMO

There are many promising psychological interventions on the horizon, but there is no clear methodology for preparing them to be scaled up. Drawing on design thinking, the present research formalizes a methodology for redesigning and tailoring initial interventions. We test the methodology using the case of fixed versus growth mindsets during the transition to high school. Qualitative inquiry and rapid, iterative, randomized "A/B" experiments were conducted with ~3,000 participants to inform intervention revisions for this population. Next, two experimental evaluations showed that the revised growth mindset intervention was an improvement over previous versions in terms of short-term proxy outcomes (Study 1, N=7,501), and it improved 9th grade core-course GPA and reduced D/F GPAs for lower achieving students when delivered via the Internet under routine conditions with ~95% of students at 10 schools (Study 2, N=3,676). Although the intervention could still be improved even further, the current research provides a model for how to improve and scale interventions that begin to address pressing educational problems. It also provides insight into how to teach a growth mindset more effectively.

6.
Adv Mater ; : e2404384, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943469

RESUMO

Films and patterns of 3D-oriented metal-organic frameworks (MOFs) afford well-ordered pore structures extending across centimeter-scale areas. These macroscopic domains of aligned pores are pivotal to enhance diffusion along specific pathways and orient functional guests. The anisotropic properties emerging from this alignment are beneficial for applications in ion conductivity and photonics. However, the structure of 3D-oriented MOF films and patterns can rapidly degrade under humid and acidic conditions. Thus, more durable 3D-ordered porous systems are desired for practical applications. Here, oriented porous polymer films and patterns are prepared by using heteroepitaxially oriented N3-functionalized MOF films as precursor materials. The film fabrication protocol utilizes an azide-alkyne cycloaddition on the Cu2(AzBPDC)2DABCO MOF. The micropatterning protocol exploits the X-ray sensitivity of azide groups in Cu2(AzBPDC)2DABCO, enabling selective degradation in the irradiated areas. The masked regions of the MOF film retain their N3-functionality, allowing for subsequent cross-linking through azide-alkyne coupling. Subsequent acidic treatment removes the Cu ions from the MOF, yielding porous polymer micro-patterns. The polymer has high chemical stability and shows an anisotropic fluorescent response. The use of 3D-oriented MOF systems as precursors for the fabrication of oriented porous polymers will facilitate the progress of optical components for photonic applications.

7.
Biochim Biophys Acta Gen Subj ; 1863(5): 925-934, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30826435

RESUMO

BACKGROUND: Actinobacteria, including the Mycobacteria, have a large component of cytochrome P450 family monooxygenases. This includes Mycobacterium tuberculosis, M. ulcerans and M. marinum, and M. vanbaalenii. These enzymes can abstract CH bonds and have important roles in natural product biosynthesis. METHODS: Two members of the bacterial CYP150 family, CYP150A5 and CYP150A6 from M. marinum, were produced, purified and characterised. The potential substrate ranges of both enzymes were analysed and the monooxygenase activity of CYP150A5 was reconstituted using a physiological electron transfer partner system. CYP150A6 was structurally characterised by X-ray crystallography. RESULTS: CYP150A5 was shown to bind various norisoprenoids and terpenoids. It could regioselectively hydroxylate ß-ionol. The X-ray crystal structure of substrate-free CYP150A6 was solved to 1.5 Å. This displayed an open conformation with short F and G helices, an unresolved F-G loop region and exposed active site pocket. The active site residues could be identified and important variations were found among the CYP150A enzymes. Haem-binding azole inhibitors were identified for both enzymes. CONCLUSIONS: The structure of CYP150A6 will facilitate the identification of physiological substrates and the design of better inhibitors for members of this P450 family. Based on the observed differences in substrate binding preference and sequence variations among the active site residues, their roles are predicted to be different. GENERAL SIGNIFICANCE: Multiple CYP150 family members were found in many bacteria and are prevalent in the Mycobacteria including several human pathogens. Inhibition and structural data are reported here for these enzymes for the first time.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Mycobacterium tuberculosis/enzimologia , Cristalografia por Raios X , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/isolamento & purificação , Modelos Moleculares , Mycobacterium tuberculosis/citologia , Filogenia
8.
Vic Stud ; 51(4): 687-712, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20210042

RESUMO

This essay examines the cultural representation of women's encounters on the fin-de-siècle street and, in particular, the uncertainties that clustered around the possibilities of mutual, or one-sided, same-sex desire accompanying such meetings. It argues, through an examination of lyric poetry, paintings, and short fiction, for the usefulness of twilight--a time of shadowy ambiguity--as a trope to suggest these uncertainities. More than this, it maintains that the lyric and the developing genre of the short story were modes ideally suited to an invocation of the fluid, the uncertain, and the unnamable. This argument is advanced through a close reading of Charlotte Mew's strange short story "Passed," which is read as representative of a transitional moment in lesbian literary history.


Assuntos
Homossexualidade Feminina , Relações Interpessoais , Literatura , Comportamento Sexual , Comportamento Social , Condições Sociais , Mulheres , Feminino , História do Século XIX , Homossexualidade Feminina/etnologia , Homossexualidade Feminina/história , Homossexualidade Feminina/psicologia , Humanos , Literatura/história , Comportamento Sexual/etnologia , Comportamento Sexual/história , Comportamento Sexual/fisiologia , Comportamento Sexual/psicologia , Condições Sociais/economia , Condições Sociais/história , Condições Sociais/legislação & jurisprudência , Simbolismo , Reino Unido/etnologia , Mulheres/educação , Mulheres/história , Mulheres/psicologia , Saúde da Mulher/economia , Saúde da Mulher/etnologia , Saúde da Mulher/história , Saúde da Mulher/legislação & jurisprudência
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