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1.
Eur J Public Health ; 34(1): 52-58, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37793003

RESUMO

BACKGROUND: The 'WHO-ASPHER Roadmap to Professionalizing the Public Health Workforce in the European Region' provides recommendations for strategic and systematic workforce planning around professionalization levers including: (i) competencies, (ii) training and education, (iii) formal organization, (iv) professional credentialing and (v) code of ethics and professional conduct as well as taxonomy and enumeration. It was based on a literature review till 2016. This scoping review aims to explore how the professionalization was documented in the literature between 2016 and 2022. METHODS: Following the Joanna Briggs Institute guidelines, we searched Medline via PubMed, Web of Science, ERIC via EBSCO and Google Scholar and included studies on professionalization levers. Four critical appraisal tools were used to assess qualitative, quantitative, mixed methods studies and grey literature. The PRISMA Extension for Scoping Reviews (PRISMA-ScR) was used for reporting. RESULTS: Eleven articles included in this review spanned 61 countries, targeting undergraduate, master's, doctoral degrees and continuing professional development. Most of these documents were reviews. About half provided a definition of the public health workforce; more than half covered the taxonomy and included information about competences, but the use of frameworks was sporadic and inconsistent. Formal organization and the necessity of a code of conduct for the public health workforce were acknowledged in only two studies. CONCLUSIONS: In spite of some efforts to professionalize the public health workforce, this process is fragmented and not fully recognized and supported. There is an urgent need to engage policymakers and stakeholders to prioritize investments in strengthening the public health workforce worldwide.


Assuntos
Mão de Obra em Saúde , Saúde Pública , Humanos , Recursos Humanos , Estudantes
2.
Nanomaterials (Basel) ; 13(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37947736

RESUMO

We present the results of a temperature-dependent photoluminescence (PL) spectroscopy study on CuInS2 quantum dots (QDs). In order to elucidate the influence of QD size on PL temperature dependence, size-selective precipitation was used to obtain several nanoparticle fractions. Additionally, the nanoparticles' morphology and chemical composition were studied using transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The obtained QDs showed luminescence in the visible-near infrared range. The PL energy, linewidth, and intensity were studied within an 11-300 K interval. For all fractions, a temperature decrease led to a shift in the emission maximum to higher energies and pronounced growth of the PL intensity down to 75-100 K. It was found that for large particle fractions, the PL intensity started to decrease, with temperature decreasing below 75 K, while the PL intensity of small nanoparticles remained stable.

3.
Materials (Basel) ; 16(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37241332

RESUMO

The environment of an underground structure is much more complex than the above-ground environment. Erosion processes are underway in soil and groundwater; groundwater seepage and soil pressure are also typical for underground environments. Alternating layers of dry and wet soil have a strong effect on concrete, and they reduce its durability. Corrosion of cement concretes is caused by the diffusion of free calcium hydroxide, located in the pores of concrete, from the volume of the cement stone to its surface, bordering on an aggressive environment, and the further transition of the substance through the phase boundary solid (concrete)-soil-aggressive environment (liquid). Due to the fact that all minerals in cement stone exist only in saturated or close-to-saturated solutions of calcium hydroxide, a decrease in the content of which in the pores of concrete as a result of mass transfer processes causes a change in the phase and thermodynamic equilibrium in the body of concrete and leads to the decomposition of highly basic compounds of cement stone and, consequently, to the deterioration of the mechanical properties of concrete (reduction in strength, modulus of elasticity, etc.). A mathematical model of mass transfer in a two-layer plate imitating the "reinforced concrete structure-layer of the soil-coastal marine area" system is proposed as a system of nonstationary partial derivative differential equations of the parabolic type with Newmann's boundary conditions inside the building and at the interface between the soil and the marine environment and with conjugating boundary conditions at the interface between the concrete and the soil. When the boundary problem of mass conductivity in the "concrete-soil" system is solved, expressions are obtained to determine the dynamics of the concentration profiles of the target component (calcium ions) in the volumes of the concrete and soil. As a result, one can select the optimum composition of concrete, having high anticorrosion properties, to extend the durability of the concrete constructions of offshore marine structures.

4.
Materials (Basel) ; 15(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36556657

RESUMO

INTRODUCTION: the article discusses the effect of the complex of active mineral additives consisting of silica and fly ash, and a fine aggregate, including finely ground natural-white quartz sand for partial replacement of river sand, on the mechanical properties of high-strength concrete containing steel fiber. MATERIALS AND METHODS: high-strength concrete containing Dramix®3D 65/35 steel fiber in the amount of 100 kg per 1 m3 of concrete mixture was suggested where 22% to 100% of river sand was replaced by finely ground white natural sand of the particle size of 5 to 1800 µm and containing the complex of active mineral additives for partial replacement of cement as part of a multicomponent binder, consisting of low-calcium fly ash of thermal power plants and silica and containing, respectively, 20, 30, 40% fly ash and from 5 to 15% silica by weight of the binder. RESULTS: research results have shown that 100% replacement of river sand with finely ground natural white sand, in concrete containing 20% of the mass as part of a multicomponent binder, fly ash and from 5 to 15% by weight of silica, contributes to the increase of its strength properties: the values of concrete compressive strength after 28 days were in the range from 118.5 to 128 MPa, tensile strength during bending and splitting, respectively, from 18.8 to 25.4 MPa and from 10.2 to 11.9 MPa, which is higher than the strength of concrete samples containing river sand. CONCLUSIONS: the achieved results have demonstrated the efficiency of using finely ground natural white sand as an alternative to river sand for producing high-strength concrete, thus helping to save the river sand resources in Vietnam. The use of fly ash and micro silicon, which are power and metallurgy wastes, as part of a multicomponent binder in order to partially replace cement reduces the carbon footprint in the production of binders and will also have a beneficial effect on environmental protection against industrial waste pollution.

5.
Nanomaterials (Basel) ; 12(14)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35889581

RESUMO

A synthesis protocol of polyvinylpyrrolidone-capped AgInS2 quantum dots in aqueous solution is reported. Nanoparticle morphology and chemical composition were studied by means of TEM, XRD, XPS, and FTIR. The obtained quantum dots were luminescent in the visible range. The photoluminescence intensity dependence on the polyvinylpyrrolidone amount was demonstrated. The wavelength of the emission maximum varied with changing the [Ag]:[In] molar ratio. The temperature dependence of the photoluminescence intensity of the polyvinylpyrrolidone-capped AgInS2 quantum dots was investigated within the temperature range of 11-294 K.

6.
Materials (Basel) ; 15(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35806821

RESUMO

This study built theoretical and practical models to evaluate the corrosion resistance of concrete for coastal offshore structures in Vietnam. A mathematical model was developed in the form of a system of nonlinear partial differential equations characterizing the diffusion "free calcium hydroxide" in a solid of a concrete structure. The model describes the process of non-stationary mass conductivity observed in the "concrete structure-marine environment" system under non-uniform arbitrary initial conditions, as well as combined boundary conditions of the second and third kind, taking into account the nonlinear nature of the coefficients of mass conductivity k and mass transfer ß. It was shown that the solution of the boundary value problem of non-stationary mass conductivity allows us to conclude about the duration of the service life of a concrete structure, which will be determined by the processes occurring at the interface: in concrete-mass conductivity, depending on the structural and mechanical characteristics of hydraulic structures, and in the liquid phase-mass transfer, determined by the conditions of interaction at the interface of the indicated phases.

7.
Brain Res Bull ; 130: 90-94, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28069436

RESUMO

Streptozotocin (STZ) is a glucosamine-nitrosourea compound used for experimental simulation of sporadic Alzheimer's disease at intracerebroventricular administration in vivo. The studies of STZ influence on neurons of central nervous system performed on the primary cultures are practically absent. We have shown the application of STZ (1-5mM) in primary culture for 48h induced strong dose-dependent death in cultured cerebellar granule neurons. This toxic effect was decreased by pyruvate, insulin partially. Using the indicator Fluo-4 AM for measurements of intracellular calcium ions and tetramethylrhodamine ethyl ester (TMRE) for detection of changes of mitochondrial membrane potential in live cells we have shown that 5 h-exposure to STZ induced intensive increase of Fluo-4 and decrease TMRE fluorescence in neurons. STZ exposure caused considerable ultrastructural alterations in granule neurons: chromatin clumping, swelling of the endoplasmic reticulum and mitochondria, and disruption of the mitochondrial cristae. Probably, STZ significantly impaired glucose metabolism and mitochondrial function that, in turn, resulted in mitochondrial membrane potential damage, excessive calcium overload and neuronal death.


Assuntos
Cerebelo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estreptozocina/toxicidade , Animais , Morte Celular , Células Cultivadas , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Neurônios/ultraestrutura , Neurotoxinas/administração & dosagem , Ratos Wistar
8.
Toxicol Lett ; 250-251: 29-34, 2016 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-27063646

RESUMO

Copper chloride (0.01mM, 2h) did not have significant influence on the survival of cerebellar granule neurons (CGNs) incubated in balanced salt solution. However, CuCl2 caused severe neuronal damage by glucose deprivation (GD). The glutamate NMDA-receptors blocker MK-801 partially and antioxidant N-acetyl-l-cysteine (NAC) or Zn(2+) chelator, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) almost entirely protected CGNs from this toxic effect. Measurements of intracellular calcium ions using Fluo-4 AM, or zinc ions with FluoZin-3 AM demonstrated that 1 h-exposure to GD induced intensive increase of Fluo-4 but not FluoZin-3 fluorescence in neurons. The supplementation of solution with CuCl2 caused an increase of FluoZin-3, Fluo-4 and CellROX Green (reactive oxygen species probe) fluorescence by GD. The stimulation of Fluo-4 but not FluoZin-3 fluorescence by copper could be prevented partially by MK-801 and as well as CellROX Green fluorescence by NAC at GD. This data imply that during GD copper ions induce intense displacement zinc ions from intracellular stores, in addition free radical production, glutamate release and Ca(2+) overload of CGNs, that causes death of neurons as a result.


Assuntos
Cerebelo/efeitos dos fármacos , Cobre/toxicidade , Glucose/deficiência , Neurônios/efeitos dos fármacos , Zinco/metabolismo , Animais , Animais Recém-Nascidos , Antioxidantes/farmacologia , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Células Cultivadas , Cerebelo/metabolismo , Cerebelo/patologia , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
9.
Environ Sci Technol ; 49(11): 6474-84, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-25815708

RESUMO

The speciation of U and Pu in soil and concrete from Rocky Flats and in particles from soils from Chernobyl, Hanford, Los Alamos, and McGuire Air Force Base and bottom sediments from Mayak was determined by a combination of X-ray absorption fine structure (XAFS) spectroscopy and X-ray fluorescence (XRF) element maps. These experiments identify four types of speciation that sometimes may and other times do not exhibit an association with the source terms and histories of these samples: relatively well ordered PuO2+x and UO2+x that had equilibrated with O2 and H2O under both ambient conditions and in fires or explosions; instances of small, isolated particles of U as UO2+x, U3O8, and U(VI) species coexisting in close proximity after decades in the environment; alteration phases of uranyl with other elements including ones that would not have come from soils; and mononuclear Pu-O species and novel PuO2+x-type compounds incorporating additional elements that may have occurred because the Pu was exposed to extreme chemical conditions such as acidic solutions released directly into soil or concrete. Our results therefore directly demonstrate instances of novel complexity in the Å and µm-scale chemical speciation and reactivity of U and Pu in their initial formation and after environmental exposure as well as occasions of unexpected behavior in the reaction pathways over short geological but significant sociological times. They also show that incorporating the actual disposal and site conditions and resultant novel materials such as those reported here may be necessary to develop the most accurate predictive models for Pu and U in the environment.


Assuntos
Plutônio/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , Acidente Nuclear de Chernobyl , Colorado , New Jersey , New Mexico , Plutônio/química , Federação Russa , Espectrometria por Raios X , Ucrânia , Urânio/química , Washington
10.
Ophthalmic Res ; 38(5): 263-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16974126

RESUMO

No experimental system exists to date for the in vitro study of retinal ganglion cell populations in a three-dimensional organotypic tissue environment. Here, we describe such a novel method for roller cultivation of adult retinas. Retinas of adult (1-3 months old) rats were cut into rectangular slices of approximately 1 mm(2). Free-floating slices were cultured on a horizontal rotating roller drum (50-60 rpm) in a dry incubator at 36.5 degrees C. During the first days of cultivation, primary flat retinal slices changed their configuration and transformed into ball-shaped tissue spheres (retinal bodies). Histological and immunocytochemical studies showed that the outer wall of the retinal bodies was formed by cell and fibre layers typical of mature retina with photoreceptors located on the outside. Initially, retinal bodies contained an inner cavity which later was completely obliterated and filled with glial cells, sprouting nerve fibres, and vascular structures. This culture system was further developed into a robust model of glutamate-induced neurotoxicity. Using a novel culture method of adult rat retina, preservation of the three-dimensional organotypic retinal cytoarchitecture was achieved, including survival of neurons in the ganglion cell layer and sprouting of nerve fibres of the axotomized retinal ganglion cells. This novel culture model promises to facilitate studies of retinal physiology and pathology.


Assuntos
Técnicas de Cultura de Células/métodos , Retina/citologia , Animais , Biomarcadores/metabolismo , Meios de Cultura , Técnica Indireta de Fluorescência para Anticorpo , Proteína Glial Fibrilar Ácida/metabolismo , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/metabolismo , Ratos , Ratos Wistar , Retina/metabolismo , Fator de von Willebrand/metabolismo
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