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1.
Artigo em Inglês | MEDLINE | ID: mdl-33000888

RESUMO

The combination of highly sensitive techniques such as electrochemiluminescence (ECL) with nanotechnology sparked new analytical applications, in particular for immunoassay-based detection systems. In this context, nanomaterials, particularly dye-doped silica nanoparticles (DDSNPs) are of high interest, since they can offer several advantages in terms of sensitivity and performance. In this work we synthesized two sets of monodispersed and biotinylated [Ru(bpy)3 ]2+ -doped silica nanoparticles, named bio-Triton@RuNP and bio-Igepal@RuNP, obtained following the reverse microemulsion method using two different types of nonionic surfactants. Controlling the synthetic procedures, we were able to obtain nanoparticles (NPs) offering highly intense signal, using tri-n-propylamine (TPrA) as coreactant, with bio-Triton@RuNps being more efficient than bio-Igepal@RuNP.

2.
Nanoscale ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001129

RESUMO

Due to an increasing requirement of clean and sustainable hydrogen energy economy, it is significant to develop new highly effective catalysts for electrochemical water splitting. In alkaline electrolyte, Platinum (Pt) shows a much slower hydrogen evolution reaction (HER) kinetics relative to acidic condition. Here, we show a versatile synthetic approach for combining different noble metals, such as Rhodium (Rh), RhPt and Pt nanoparticles, with carbon forming noble metal nanoparticles/nanocarbon composites, denoted as Rh(nP)/nC, RhPt(nP)/nC and Pt(nP)/nC, respectively. It was found that in alkaline media these composites exhibited higher performance for the HER than the commercial Pt/C. In particular, Rh(nP)/nC displayed a small overpotential of 44 mV at a current density of 5 mA cm-2 and a low Tafel slope of 50 mV dec-1. Meanwhile, it also showed a comparable activity for the oxygen evolution reaction (OER) to the benchmarking catalyst RuO2. The superior HER and OER performance benefits from the very small size of nanoparticles and synergy between carbon support and nanoparticles.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32874852

RESUMO

Background: : The COVID-19 outbreak has led to an unprecedented crisis in Spain. After Italy, the spread of the virus was quick, and Spain became the second epicenter in Europe by number of cases and deceased. To tackle the outbreak and contain the spread, the Spanish authorities undertook exceptional measures based on a generalized lockdown by which the majority of the economic activity ceased for several weeks. Objectives: : The goal of this paper is to examine the spread of COVID-19 in Spain from February to May 2020, as well as the public policies and technologies used to contain the evolution of the pandemic. In particular it aims to assess the effectivity of the policies applied within the different autonomous communities. Cases and deaths are presented until August as well as the main changes in containment and mitigation measures. Methods: : Data was collected from various official sources, including government reports, press releases and datasets provided by national and international level institutions. Results: : We show that the main measure to contain the spread of the pandemic was a stringent confinement policy enforced through fines. It resulted in a substantial reduction in the mobility and the economic activity. At a regional level, the negative consequences of the crisis affected differently across regions.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32874858

RESUMO

Objectives: This paper aims at providing an overview of the COVID-19 situation, health policies, and economic impact in Greece, Iceland, New Zealand, and Singapore. The four countries were chosen due to their ability to contain the spread and mitigate the effects of COVID-19 on their societies. Methods: We use document analysis based on the available national reports, media announcements, official coronavirus websites and governmental decrees in each of the four countries starting from the 1st of January o the 9th of August announcements. We apply a policy gradient to compare and examine the policies implemented in the four countries. Findings: The four countries have different demographic, epidemiological, socioeconomic profiles but managed to control the pandemic at an early stage in terms of total number of positive cases. The four countries managed to absorb the health system shock and decrease the case fatality ratio of COVID-19. Early interventions were crucial to avoid expected life lost in case of no early lockdown. The pandemic triggered several economic stimulus and relief measures in the four countries; the impact or the economic rebound is yet to be fully observed. Conclusions: We conclude that early, proactive and strict interventions along with leveraging previous experience on communicable diseases and the evolution of testing strategies are key lessons that can be synthesized from the interventions of the four countries and that could be useful for a potential second wave or similar pandemics.

6.
Health Policy Technol ; : 449, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32874863

RESUMO

Background: COVID-19 reached Latin-American countries slightly later than European countries, around February/March, allowing some emergency preparedness response in countries characterized by low health system capacities and socioeconomic disparities. Objective: This paper focuses on the first months of the pandemic in five Latin American countries: Brazil, Chile, Colombia, Ecuador and Peru. It analyses how the pre-pandemic context, and the government's responses in terms of containment and mitigation and economic measures have affected the COVID-19 health outcomes. Methods: Extensive qualitative document analysis was conducted focused on publicly-available epidemiological data and federal and state/regional policy documents since the beginning of the pandemic. Results: The countries were quick to implement stringent COVID-19 measures and incrementally scaled up their health systems capacity, although tracing and tracking have been poor. All five countries have experienced a large number of cases and deaths due to COVID-19. The analysis on the excess deaths also shows that the impact in deaths is far higher than the official numbers reported to date for some countries. Conclusion: Despite the introduction of stringent measures of containment and mitigation, and the scale up of health system capacities, pre-pandemic conditions that characterize these countries (high informal employment, and social inequalities) have undermined the effectiveness of the countries' responses to the pandemic. The economic support measures put in place were found to be too timid for some countries and introduced too late in most of them. Additionally, the lack of a comprehensive strategy for testing and tracking has also contributed to the failure to contain the spread of the virus.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32874859

RESUMO

OBJECTIVES: Pandemics pressure national governments to respond swiftly. Mitigation efforts created an imbalance between population health, capacity of the healthcare system and economic prosperity. Each pandemic arising from a new virus is unknown territory for policy makers, and there is considerable uncertainty of the appropriateness of responses and outcomes. METHODS: A qualitative approach was used to review mixed sources of data including Australian reports, official government publications, and COVID-19 data to discern robust future responses. Publicly available epidemiological and economic data were utilised to provide insight into the impact of the pandemic on Australia's healthcare system and economy. RESULTS: Policies implemented by Australian government to mitigate the spread of COVID-19 impacted the healthcare sector and the economy. This paper incorporates lessons learned to inform optimal economic preparedness. The rationale for an economic response plan concomitant with the health pandemic plan is explored to guide Australian government policy makers in ensuring holistic and robust solutions for future pandemics. CONCLUSIONS: In future, an Australian Economic Pandemic Response Plan will aid in health and economic system preparedness, whilst a strong Australian economy and strategic planning will ensure resilience to future pandemics.

8.
Phys Chem Chem Phys ; 22(27): 15413-15417, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32601627

RESUMO

In this work, we quantify the electrogenerated chemiluminescence arising from the reaction of electrogenerated tris(bipyridine)ruthenium(iii) with hydroxyl ions, in terms of emission intensity and reaction rate. Different electrode materials (glassy carbon and boron-doped diamond) and different supporting electrolytes (perchlorate, phosphate, and carbonate) were investigated with pH variation. Relative quantification of the electrogenerated chemiluminescence was achieved using the Ru(bpy)32+/tri-n-propylamine system, taken as a reference, with relative emission as low as 600 and 230 times that observed at the same coreactant concentration and the same pH, respectively. The kinetics was investigated by foot of the wave analysis of cyclic voltammetry to measure the turnover frequency of the reaction.

9.
Nat Commun ; 11(1): 2668, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472057

RESUMO

Electrochemiluminescence (ECL) is a powerful transduction technique with a leading role in the biosensing field due to its high sensitivity and low background signal. Although the intrinsic analytical strength of ECL depends critically on the overall efficiency of the mechanisms of its generation, studies aimed at enhancing the ECL signal have mostly focused on the investigation of materials, either luminophores or coreactants, while fundamental mechanistic studies are relatively scarce. Here, we discover an unexpected but highly efficient mechanistic path for ECL generation close to the electrode surface (signal enhancement, 128%) using an innovative combination of ECL imaging techniques and electrochemical mapping of radical generation. Our findings, which are also supported by quantum chemical calculations and spin trapping methods, led to the identification of a family of alternative branched amine coreactants, which raises the analytical strength of ECL well beyond that of present state-of-the-art immunoassays, thus creating potential ECL applications in ultrasensitive bioanalysis.


Assuntos
Biomarcadores/análise , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletroquímica/métodos , Medições Luminescentes/métodos , Técnicas de Química Analítica , Físico-Química/métodos , Luminescência
10.
BMJ Open ; 10(3): e035870, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32161162

RESUMO

INTRODUCTION: In order to properly evaluate the efficacy of orthopaedic procedures, rigorous, randomised controlled sham surgery trial designs are necessary. However, randomised controlled trials (RCTs) for surgery involving a placebo are ethically debated and difficult to conduct with many failing to reach their desired sample size and power. A review of the literature on barriers and enablers to recruitment, and patient and surgeon attitudes and preferences towards sham surgery trials, will help to determine the characteristics necessary for successful recruitment. METHODS AND ANALYSIS: This review will scope the diverse literature surrounding sham surgery trials with the aim of informing a discrete choice experiment to empirically test patient and surgeon preferences for different sham surgery trial designs. The scoping review will be conducted in accordance with the methodological framework described in Arksey and O'Malley (2005) and reported using the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols extension for Scoping Reviews. The review will be informed by a systematic search of Medline, Embase, PsycInfo, CINAHL and EconLit databases (from database inception to 21 June 2019), a Google Scholar search, and hand searching of reference lists of relevant studies or reviews. Studies or opinion pieces that involve patient, surgeon or trial characteristics, which influence the decision to participate in a trial, will be included. Study selection will be carried out independently by two authors with discrepancies resolved by consensus among three authors. Data will be charted using a standardised form, and results tabulated and narratively summarised with reference to the research questions of the review. ETHICS AND DISSEMINATION: The findings from this review will inform the design of a discrete choice experiment around willingness to participate in surgical trials, the outcomes of which can inform decision and cost-effectiveness models of sham surgery RCTs. The qualitative information from this review will also inform patient-centred outcomes research. The review will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: CRD42019133296.

11.
J Am Chem Soc ; 142(3): 1518-1525, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31922404

RESUMO

An electrogenerated chemiluminescence (ECL) system by in situ coreactant production, where Ru(bpy)32+ emission is generated at a boron-doped diamond (BDD) electrode, is presented. The system takes advantage of the unique properties of BDD to promote oxidation of carbonate (CO32-) into peroxydicarbonate (C2O62-), which further reacts with water to form hydrogen peroxide (H2O2), which acts as a coreactant for Ru(bpy)32+ ECL. Investigation of the mechanism reveals that ECL emission is triggered by the reduction of H2O2 to hydroxyl radicals (OH•), which later react with the reduced Ru(bpy)3+ molecules to form excited states, followed by light emission. The ECL signal was found to increase with the concentration of CO32-; therefore, with the concentration of electrogenerated H2O2, although at the same time, higher concentrations of H2O2 can quench the ECL emission, resulting in a decrease in intensity. The carbonate concentration, pH, and oxidation parameters, such as potential and time, were optimized to find the best emission conditions.

12.
Angew Chem Int Ed Engl ; 58(30): 10276-10280, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31106469

RESUMO

Controlled nitrogen-doping is a powerful methodology to modify the properties of carbon nanostructures and produce functional materials for electrocatalysis, energy conversion and storage, and sensing, among others. Herein, we report a wall- and hybridisation-selective synthetic methodology to produce double-walled carbon nanotubes with an inner tube doped exclusively with graphitic sp2 -nitrogen atoms. Our measurements shed light on the fundamental properties of nitrogen-doped nanocarbons opening the door for developing their potential applications.

13.
Int J Ment Health Nurs ; 28(4): 971-979, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31081282

RESUMO

In recent years, there has been a move away from the medical model of care for people with borderline personality disorder, as hospital admission comes with a number of risks and potential adverse consequences. Although long-term outpatient-based therapy is successful, this may not be an option for those whose condition is in need of stabilisation. Brief admission for crisis intervention has been successful and is now widely used; however, research that examines both the staff and clients' perceptions of a dedicated programme is lacking. Open Borders is a residential recovery-oriented programme that provides brief admission, respite, and phone coaching for people with borderline personality disorder who are heavy users of the public mental health system. In this paper, the authors report the perspectives of clients and staff of the Open Borders programme obtained through semi-structured interviews. Thematic analysis of client and staff perspectives identified four common themes: 'Benefits of the programme', 'Enhanced client outcomes', 'Impact of the physical environment', and 'Ways of enhancing service delivery'. In addition, analysis of the staff perspectives included the theme 'Emotional impact on staff'. Benefits of the programme included the small supportive team approach, flexibility of the staff to spend time with the clients to tailor care, and the relaxed, welcoming environment. Enhanced client outcomes included a reduction in self-harming and hospitalization and an increase in self-efficacy. These results support the move away from the medical model and the empowerment of clients to self-manage their symptoms while fostering hope and self-determination.


Assuntos
Transtorno da Personalidade Borderline/terapia , Serviços de Saúde Mental , Adulto , Atitude do Pessoal de Saúde , Feminino , Pessoal de Saúde/psicologia , Humanos , Entrevistas como Assunto , Masculino , Satisfação do Paciente
14.
Anal Chem ; 90(21): 12959-12963, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30399650

RESUMO

We report on the use of boron doped diamond electrodes for the electrochemiluminescence (ECL) of the coreactant peroxydisulfate and the luminophore ruthenium(II)-tris(2,2'-bipyridine). Compared to common electrode materials (i.e., Pt, Au, glassy carbon), boron doped diamond has a large overpotential for the evolution of hydrogen in aqueous electrolyte solutions. This intrinsic feature enables reductive-oxidation ECL with peroxydisulfate to be obtained without interference from hydrogen evolution and with high reproducible signals and stable emission. We investigated the effects of the peroxydisulfate concentration and the pH on the ECL emission to find the optimal conditions for enhancing the signal.

15.
J Am Chem Soc ; 140(44): 14753-14760, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30336008

RESUMO

Herein is reported a surface-confined microscopy based on electrochemiluminescence (ECL) that allows to image the plasma membrane of single cells at the interface with an electrode. By analyzing photoluminescence (PL), ECL and AFM images of mammalian CHO cells, we demonstrate that, in contrast to the wide-field fluorescence, ECL emission is confined to the immediate vicinity of the electrode surface and only the basal membrane of the cell becomes luminescent. The resulting ECL microscopy reveals details that are not resolved by classic fluorescence microscopy, without any light irradiation and specific setup. The thickness of the ECL-emitting regions is ∼500 nm due to the unique ECL mechanism that involves short-lifetime electrogenerated radicals. In addition, the reported ECL microscopy is a dynamic technique that reflects the transport properties through the cell membranes and not only the specific labeling of the membranes. Finally, disposable transparent carbon nanotube (CNT)-based electrodes inkjet-printed on classic microscope glass coverslips were used to image cells in both reflection and transmission configurations. Therefore, our approach opens new avenues for ECL as a surface-confined microscopy to develop single cell assays and to image the dynamics of biological entities in cells or in membranes.


Assuntos
Membrana Celular/química , Técnicas Eletroquímicas , Medições Luminescentes , Animais , Células CHO , Células Cultivadas , Cricetulus , Fluorescência , Propriedades de Superfície
16.
J Pediatr Nurs ; 43: e18-e25, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30139704

RESUMO

PURPOSE: This study aimed to: (1) investigate the extent to which Family Centered Care (FCC) principles are currently applied in clinical practice by healthcare providers working in inpatient units; (2) evaluate the extent to which FCC principles are perceived as necessary; and (3) examine the associations between FCC principles and socio-demographic and job characteristics of participants. Design and Methods A cross-sectional study was conducted at a large pediatric hospital using the Italian version of the FCC Questionnaire Revised (FCCQ-R). Univariate and multivariate analyses were performed. RESULTS: Data from 469 healthcare providers were used for analysis. Scores for the FCC daily practices (Current activities) were significantly lower than those for their perceived necessity (Necessary activities) (p < .001). Participants who were male, younger, with work experience >20 years and working in rehabilitation reported a significantly higher perception of Current activities of FCC than others. The older and the more educated the participants, the greater was the perceived necessity of FCC activities. Female, older, and less experienced participants employed by the hospital but not working in the rehabilitation setting perceived a greater gap between Necessary and Current activities of FCC. CONCLUSIONS: Scores for the Current and Necessary activities of FCC were lower than those reported in other studies. The lower scores in the Current activities and the significant gap can be due to organizational barriers or lack of skills, but the lower scores in the Necessary activities should be interpreted as a deficit of knowledge about FCC. PRACTICE IMPLICATIONS: There is a need for further education about FCC in order to increase its perceived relevance in clinical practice.


Assuntos
Atitude do Pessoal de Saúde , Pessoal de Saúde/organização & administração , Hospitais Pediátricos/organização & administração , Assistência Centrada no Paciente/organização & administração , Inquéritos e Questionários , Adulto , Análise de Variância , Criança , Pré-Escolar , Estudos Transversais , Assistência à Saúde , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Enfermagem Pediátrica/métodos , Percepção , Adulto Jovem
17.
Nanoscale ; 10(21): 9908-9916, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29790558

RESUMO

Hybrid systems have great potential for a wide range of applications in chemistry, physics and materials science. Conjugation of a biosystem to a molecular material can tune the properties of the components or give rise to new properties. As a workhorse, here we take a C60@lysozyme hybrid. We show that lysozyme recognizes and disperses fullerene in water. AFM, cryo-TEM and high resolution X-ray powder diffraction show that the C60 dispersion is monomolecular. The adduct is biocompatible, stable in physiological and technologically-relevant environments, and easy to store. Hybridization with lysozyme preserves the electrochemical properties of C60. EPR spin-trapping experiments show that the C60@lysozyme hybrid produces ROS following both type I and type II mechanisms. Due to the shielding effect of proteins, the adduct generates significant amounts of 1O2 also in aqueous solution. In the case of type I mechanism, the protein residues provide electrons and the hybrid does not require addition of external electron donors. The preparation process and the properties of C60@lysozyme are general and can be expected to be similar to other C60@protein systems. It is envisaged that the properties of the C60@protein hybrids will pave the way for a host of applications in nanomedicine, nanotechnology, and photocatalysis.


Assuntos
Fulerenos/química , Muramidase/química , Água/química , Detecção de Spin
18.
Chem Commun (Camb) ; 54(39): 4999-5002, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29707706

RESUMO

Electrochemiluminescence (ECL) generated by a monolayer of a spirobifluorene derivative covalently bound onto an indium tin oxide (ITO) substrate is reported for the first time. Our approach allows the efficient preparation homogeneous and patterned substrates through micromolding in capillaries (MIMIC), and opens novel scenarios for multicolour ECL applications.

19.
Chemistry ; 24(46): 11954-11960, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-29603481

RESUMO

Salophens and Salens are Schiff bases generated through the condensation of two equivalents of salicylaldehyde with either 1,2-phenylenediamines or aliphatic diamines, respectively. Both ligands have been extensively exploited as key building blocks in coordination chemistry and catalysis. In particular, their metal complexes have been widely used for various catalytical transformations with high yield and selectivity. Through the modification of the phenol unit it is possible to tune the steric hindrance and electronic properties of Salophen and Salen. The introduction of long aliphatic chains in salicylaldehydes can be used to promote their self-assembly into ordered supramolecular structures on solid surfaces. Herein, we report a novel method towards the facile synthesis of robust and air-stable [Al(Salophen)] derivatives capable of undergoing spontaneous self-assembly at the graphite/solution interface forming highly-ordered nanopatterns. The new synthetic approach relies on the use of [MeAlIII (Salophen)] as a building unit to introduce, via a simple acid/base reaction with functionalized acidic phenol derivatives, selected frameworks integrating multiple functions for efficient surface decoration. STM imaging at the solid/liquid interface made it possible to monitor the formation of ordered supramolecular structures. In addition, the redox properties of the Salophen derivatives functionalized with ferrocene units in solution and on surface were unraveled by cyclic voltammetry. The use of a five-coordinate aluminum alkyl Salophen precursor enables the tailoring of new Salophen molecules capable of undergoing controlled self-assembly on HOPG, and thereby it can be exploited to introduce multiple functionalities with subnanometer precision at surfaces, ultimately forming ordered functional patterns.

20.
Front Public Health ; 5: 325, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29276704

RESUMO

Universal health coverage (UHC) is the big objective in health policy which several countries are seeking to achieve. Egypt is no different and its endeavors to attain UHC have been going on since the 1960s. This article discusses the status of UHC in Egypt using theories of political science and economics by analyzing the historical transformations in the Egyptian health system and its institutional settings. This article then specifically examines the path dependence theory against the sociopolitical background of Egypt and assesses any pattern between the theory and the current UHC status in Egypt. The important finding of this analysis is that the health policies and reforms in Egypt have been significantly influenced and limited by its historical institutional structure and development. Both the health policies and the institutional settings adopted a dependent path that limited Egypt's endeavors to achieve the universal coverage. This dependent path also yielded many of the present-day challenges as in the weaknesses of the healthcare financing system and the inability to extend health coverage to the poor and the informal sector. These challenges subsequently had a negative impact on the accessibility of the healthcare services.

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