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1.
Mater Today Commun ; 34: 105192, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36570033

RESUMO

We carried out theoretical and experimental analyses of ZnO and ZnS nanoparticles as smart semiconductor materials in light-activated antimicrobial coating for application in masks. We used low-cost hydrothermally processable precursors to direct the growth of the coatings on cotton fabric. Both ZnO and ZnS coatings had high reactivities as disinfection agents in photocatalysis reactions for the degradation of a methylene blue dye solution. Also, these coatings showed excellent UV protection properties. For understanding at the molecular level, the broad-spectrum biological activities of the ZnO and ZnS coatings against Fusarium Oxysporum fungi, Escherichia coli bacteria, and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus and their variants, were investigated computationally. Hexagonal Zn6O6 and Zn6S6 clusters were used as models for the simulations through excited- and ground-state calculations. The theoretical findings show that changes in the local chemical environment in these excited systems have a profound impact on their physical and chemical properties and thus, can provide a better understanding to engineer new functional materials in light-activated antimicrobial coatings for the mitigation of SARS-CoV-2 infection.

2.
Acta Neurochir (Wien) ; 163(2): 423-440, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33354733

RESUMO

BACKGROUND: Due to the lack of high-quality evidence which has hindered the development of evidence-based guidelines, there is a need to provide general guidance on cranioplasty (CP) following traumatic brain injury (TBI), as well as identify areas of ongoing uncertainty via a consensus-based approach. METHODS: The international consensus meeting on post-traumatic CP was held during the International Conference on Recent Advances in Neurotraumatology (ICRAN), in Naples, Italy, in June 2018. This meeting was endorsed by the Neurotrauma Committee of the World Federation of Neurosurgical Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and several other neurotrauma organizations. Discussions and voting were organized around 5 pre-specified themes: (1) indications and technique, (2) materials, (3) timing, (4) hydrocephalus, and (5) paediatric CP. RESULTS: The participants discussed published evidence on each topic and proposed consensus statements, which were subject to ratification using anonymous real-time voting. Statements required an agreement threshold of more than 70% for inclusion in the final recommendations. CONCLUSIONS: This document is the first set of practical consensus-based clinical recommendations on post-traumatic CP, focusing on timing, materials, complications, and surgical procedures. Future research directions are also presented.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Conferências de Consenso como Assunto , Craniotomia/normas , Procedimentos de Cirurgia Plástica/normas , Humanos , Hidrocefalia/cirurgia , Itália
3.
Rev Sci Instrum ; 91(1): 013907, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012586

RESUMO

Liquid metal catalysts (LMCats) (e.g., molten copper) can provide a new mass-production method for two-dimensional materials (2DMs) (e.g., graphene) with significantly higher quality and speed and lower energy and material consumption. To reach such technological excellence, the physicochemical properties of LMCats and the growth mechanisms of 2DMs on LMCats should be investigated. Here, we report the development of a chemical vapor deposition (CVD) reactor which allows the investigation of ongoing chemical reactions on the surface of a molten metal at elevated temperatures and under reactive conditions. The surface of the molten metal is monitored simultaneously using synchrotron x-ray scattering, Raman spectroscopy, and optical microscopy, thereby providing complementary information about the atomic structure and chemical state of the surface. To enable in situ characterization on a molten substrate at high temperatures (e.g., ∼1370 K for copper), the optical and x-ray windows need to be protected from the evaporating LMCat, reaction products, and intense heat. This has been achieved by creating specific gas-flow patterns inside the reactor. The optimized design of the reactor has been achieved using multiphysics COMSOL simulations, which take into account the heat transfer, fluid dynamics, and transport of LMCat vapor inside the reactor. The setup has been successfully tested and is currently used to investigate the CVD growth of graphene on the surface of molten copper under pressures ranging from medium vacuum up to atmospheric pressure.

4.
Nat Prod Res ; 34(19): 2832-2836, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30931612

RESUMO

The extraction conditions and chromatographic analysis from seeds of Inga edulis were optimized and provided one anthocyanin from aqueous fraction and a mixture of three anthocyanins from methanolic fraction. The pure anthocyanin obtained was subjected to structural modifications and the products obtained were subjected to chemical and pharmacological assays, as well as quantum chemical calculations based on DFT and TD-DFT methods. Hence, the anthocyanin fractions were evaluated for their chemical-pharmacological potential through chemical and biological assays: antioxidant activity by the DPPH, determination of the Solar Protection Factor (SPF) and cytotoxic activity (hepatocellular carcinoma infected with hepatitis C virus). The results indicated that even the anthocyanin and derivatized compounds having high antioxidant potential showed an SPF lower than six, which is lower than the minimum accepted by current Brazilian legislation. In addition, none of compounds presented significant cytotoxic activity against the tumour cell line studied.


Assuntos
Antocianinas/química , Antocianinas/farmacologia , Fabaceae/química , Antocianinas/análise , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Brasil , Teoria da Densidade Funcional , Frutas/química , Células Hep G2/virologia , Hepacivirus/patogenicidade , Humanos , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
5.
Eur J Phys Rehabil Med ; 51(6): 705-16, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26334361

RESUMO

BACKGROUND: It is unclear whether the BBS is an effective tool for the measurement of early postural control impairments in patients with Parkinson's disease (PD). AIM: The aim of this paper was to evaluate BBS' content validity, internal construct validity, reliability and targeting in patients with PD within the Rasch analysis framework. DESIGN: Observational, cross-sectional study. SETTING: Outpatient Rehabilitation Unit. POPULATION: A sample of 285 outpatients with PD. METHODS: The content validity of the BBS was assessed using standard linking techniques. The BBS was administered by trained physiotherapists. The data collected then underwent Rasch analysis. RESULTS: Content validity analysis showed a lack of items assessing postural responses to tripping and slips and stability during walking. On Rasch analysis, the BBS failed the requirements of monotonicity, local independence, unidimensionality and invariance. After rescoring 7 items, grouping of locally dependent items into testlets, and deletion of the static sitting balance item because mistargeted and underdiscriminating, the Rasch-modified BBS for PD (BBS-PD) showed adequate internal construct validity (χ(2)24=39.693; P=0.023), including absence of differential item functioning (DIF) across gender and age, and was, as a whole, sufficiently precise for individual person measurement (PSI=0.894). However, the scale was not well targeted to the sample in view of the prevalence of higher scores. CONCLUSION: This study demonstrated the internal construct validity and reliability of the BBS-PD as a measurement tool for patients with PD within the Rasch analysis framework. However, the lack of items critical to the assessment of postural control impairments typical of PD, affected negatively the targeting, so that a significant percentage of patients was located in the higher ability range of the measurement continuum, where precision of measurement is reduced. CLINICAL REHABILITATION IMPACT: These findings suggest that the BBS, even if modified, may not be an effective tool for the measurement of early postural control in patients with PD.


Assuntos
Avaliação da Deficiência , Doença de Parkinson/fisiopatologia , Equilíbrio Postural/fisiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Psicometria , Reprodutibilidade dos Testes , Medição de Risco , Análise e Desempenho de Tarefas
6.
Dalton Trans ; 44(7): 3159-75, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25579134

RESUMO

The focus of this paper is on the analysis of the structural and electronic order-disorder effects at long, medium and short ranges of titanium dioxide (TiO2) nanoparticles synthesized by the sol-gel process followed by the microwave-assisted solvothermal (MAS) method at low temperatures and short reaction times. X-ray diffraction (XRD), Rietveld refinement, micro-Raman (MR) spectroscopy, transmission electron microscopy (TEM) and X-ray spectroscopy (EDX) were used to characterize the TiO2 nanoparticles. Optical properties were investigated by ultraviolet-visible (UV-vis) and photoluminescence (PL) measurements performed at room temperature. XRD and Rietveld refinement confirmed the presence of the anatase and brookite phases; nonetheless anatase is the major phase. The X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of only Ti(4+) but the nonstoichiometry revealed that TiO2 NPs contain defects assigned to oxygen vacancies that lead to structural and electronic order-disorder effects observed by band gap narrowing and PL wide band emission. These intermediary energy levels (shallow and deep levels) created within the band gap act as acceptors/donors of electrons and recombination centers. The oxygen vacancies (VO(x), VO˙ and VO˙˙) responsible by degree of structural order-disorder are related to distortions (tilts) on the [TiO6] octahedron and changes in the bond lengths and bond angles between oxygen and titanium atoms that gave rise to new species of cluster makers such as [TiO6]', [TiO5·VO(x)], [TiO5·VO˙] and [TiO5·VO˙˙]. This structural transformation is consistent with a redistribution of electron density from highly ordered [TiO6](x) clusters which form distorted [TiO6]' as well as complex [TiO5·VO(x)], [TiO5·VO˙] and [TiO5·VO˙˙] clusters assigned to oxygen vacancies which were understood as displacements in the oxygen atoms' position in the bond lengths (Ti-O).

7.
Phys Chem Chem Phys ; 16(37): 20127-37, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25133930

RESUMO

The influence of tetrabutylammonium hydroxide on the phase composition (cubic zinc blende versus hexagonal wurtzite) of ZnS nanoparticles was studied. The ZnS nanoparticles were prepared by a microwave-assisted solvothermal method, and the phase structure and optical properties along with the growth process of ZnS nanoparticles were studied. We report XRD, FE-SEM, EDXS, UV-vis and PL measurements, and first-principles calculations based on TDDFT methods in order to investigate the structural and electronic properties and the growth mechanism of ZnS nanostructures. The effects as well as the merits of microwave heating on the process and characteristics of the obtained ZnS nanostructures and their performance are reported.

8.
Eur J Phys Rehabil Med ; 48(3): 443-54, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22510676

RESUMO

BACKGROUND: Effective discharge planning is increasingly recognised as a critical component of hospital-based Rehabilitation. The BRASS index is a risk screening tool for identification, shortly after hospital admission, of patients who are at risk of post-discharge problems. AIM: To evaluate the internal construct validity and reliability of the Blaylock Risk Assessment Screening Score (BRASS) within the rehabilitation setting. DESIGN: Observational prospective study. SETTING: Rehabilitation ward of an Italian district hospital. POPULATION: One hundred and four consecutively admitted patients. METHODS: Using classical psychometric methods and Rasch analysis (RA), the internal construct validity and reliability of the BRASS were examined. Also, external and predictive validity of the Rasch-modified BRASS (RMB) score were determined. RESULTS: Reliability of the original BRASS was low (Cronbach's alpha=0.595) and factor analyses showed that it was clearly multidimensional. A RA, based on a reduced 7-BRASS item set (RMB), satisfied model's expectations. Reliability was 0.777. The RMB scores strongly correlated with the original BRASS (rho=0.952; P<0.000) and with FIM™ admission scores (rho=-0.853; P<0.000). A RMB score of 12 was associated with an increased risk of nursing home admission (RR=2.1, 95%CI=1.7-2.5), whereas a score of 17 was associated to a higher risk of length of stay >28 days (RR=7.6, 95%CI=1.8-31.9). CONCLUSION: This study demonstrated that the original BRASS was multidimensional and unreliable. However, the RMB holds adequate internal construct validity and is sufficiently reliable as a predictor of discharge problems for group, but not individual use. CLINICAL REHABILITATION IMPACT: The application of tools and methods (such as the BRASS Index) developed under the biomedical paradigm in a Physical and Rehabilitation Medicine setting may have limitations. Further research is needed to develop, within the rehabilitation setting, a valid measuring tool of risk of post-discharge problems at the individual level.


Assuntos
Avaliação da Deficiência , Pessoas com Deficiência/reabilitação , Previsões , Alta do Paciente , Psicometria/métodos , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
9.
Eur J Phys Rehabil Med ; 46(3): 389-99, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20927005

RESUMO

AIM: The aim of this study was to evaluate which neurological impairments on discharge from rehabilitation services are associated with a worse outcome in terms of health related-quality of life (HRQoL) one year after stroke. METHODS: We enrolled 528 first-time stroke patients in a multicenter observational study involving 18 Italian inpatients rehabilitation centers. Neurological impairment-related factors, socio-demographic and general clinical variables and process indicators were considered independent variables at discharge. Outcome was represented by the following dependent variables of HRQoL: EuroQoL-5D questionnaire (5D-EQoL) and its derived index (Eq-Index) and a Visual Analogue Score (QoL-VAS). RESULTS: The strongest predictors of lower HRQoL were an incomplete limbs motor recovery. An incomplete lower limb motor recovery was associated with a lower HRQoL only in the "mobility" domains, whereas a incomplete upper limb motor recovery could predict a lower HRQoL in all domains except "mobility". Regarding cognitive impairments, the presence of neglect at discharge was associated with a lower HRQoL in "self-care", "pain-discomfort" and "anxiety-depression". Female gender, presence of urinary catheter seemed to exert a much lesser role in predicting HRQoL. CONCLUSION: The results of this study suggest that upper limb motor impairments may have a detrimental impact on the patient's perceived HRQoL one year after stroke.


Assuntos
Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia , Atividades Cotidianas , Idoso , Feminino , Humanos , Itália , Tempo de Internação , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Observação , Alta do Paciente , Centros de Reabilitação , Índice de Gravidade de Doença , Perfil de Impacto da Doença , Reabilitação do Acidente Vascular Cerebral , Extremidade Superior/fisiopatologia , Cateterismo Urinário/psicologia
10.
Electroencephalogr Clin Neurophysiol ; 104(4): 312-21, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9246068

RESUMO

We evaluated subcortical and cortical somatosensory evoked potentials (SEPs) in response to posterior tibial nerve stimulation in 4 experimental conditions of foot movement and compared them with the baseline condition of full relaxation. The experimental conditions were: (a) active flexion-extension of the stimulated foot; (b) active flexion-extension of the non-stimulated foot; (c) passive flexion-extension of the stimulated foot in complete relaxation; (d) tonic active flexion of the stimulated foot. We analyzed latencies and amplitudes of the subcortical P30 potential, of the contralateral pre-rolandic N37 and P50 responses and of the P37, N50 and P60 potentials recorded over the vertex. Latencies did not vary in any of the paradigms. The amplitude of subcortical P30 potential did not change during any of the paradigms. Among the cortical waves, P37, N50 and P60 amplitudes were significantly attenuated in all conditions except active movement of the non-stimulated foot (b). This attenuation was less during passive (c) than during active movements of the stimulated foot (a and d). The contralateral pre-rolandic waves N37 and P50 showed no significant decrease during any of the paradigms. These results suggest that gating occurs rostrally to the cervico-medullary junction, probably at cortical level. The different behavior of N37, P50 and P37, N50 cortical responses during movement of the stimulated foot provides evidence suggestive of a highly localized gating process occurring at cortical level. These potentials could reflect activation of separate, functionally distinct generators.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Pé/fisiologia , Movimento/fisiologia , Adulto , Encéfalo/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Nervo Tibial/fisiologia
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