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1.
BMC Public Health ; 24(1): 70, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166976

RESUMO

BACKGROUND: Early childhood caries (ECC) is one of the most common chronic diseases among children. In Poland 86.9% of six-year-olds have ECC. One of the factors determining adherence to ECC prophylaxis and oral hygiene is mothers' knowledge. The aim of this study was to assess the level of knowledge demonstrated by pregnant women about ECC prevention and oral hygiene, and to analyse the determinants of this knowledge. METHODS: A quantitative survey was conducted using Computer Assisted Telephone Interview technique on a randomly selected representative sample of 1,000 women over the age of 18 in their second and third trimesters of pregnancy. The significance level was established at 0.05 and p-values were presented as: p < 0.05, p < 0.01 and p < 0.001. RESULTS: The highest percentage of wrong or "I don't know" answers were related to questions about: the number of free dental check-ups for children (76.8%), the date of the child's first visit to the dentist (66.5%), the age when the child has mixed dentition (72.2%). Women with higher education had better knowledge than women with lower or secondary education. Women with good and very good financial situation showed a higher level of knowledge compared to women with average, bad and very bad financial situation. CONCLUSIONS: When developing prevention strategies and educational programs as part of prenatal care for women to reduce the incidence of ECC, it is important to take into account the identified areas that need support and specific target groups (mothers with lower socioeconomic status).


Assuntos
Cárie Dentária , Gestantes , Criança , Humanos , Feminino , Pré-Escolar , Gravidez , Adulto , Pessoa de Meia-Idade , Higiene Bucal , Polônia , Suscetibilidade à Cárie Dentária , Mães , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle
2.
Materials (Basel) ; 16(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36676245

RESUMO

Just a few days ago, the world population, as expected, surpassed 8 billion [...].

3.
Artigo em Inglês | MEDLINE | ID: mdl-38550558

RESUMO

Biomaterials undergo a transformative journey, from their origin as renewable resources to the manufacturing plants where they are processed and stored, until they fulfill their intended therapeutic or diagnostic purposes and become medical waste. However, during this life cycle, biomaterials can be susceptible to contamination and subsequent degradation through various mechanisms such as hydro-mechanical, thermal, or biochemical processes in water, soil, or air. These factors raise significant concerns regarding biological safety. Additional complexities arise from the potential amalgamation of biomaterials with other materials, either of the same kind or different types. Use of biomaterials influences their porosity, surface chemistry, and structural strength, and these factors affect biomaterials' reusability. Given the multitude of materials, processing parameters, sustainability requirements, and the limitation of natural resources, the recycling of biomaterials becomes necessary. Unfortunately, this topic has received limited attention thus far. In this context, this perspective provides a brief overview, analysis, and classification of reports on biomaterials recycling, aiming to initiate a discussion on this frequently overlooked subject. We highlight the challenges related to energy consumption and environmental pollution. However, the lack of established protocols and reporting on biomaterials recycling prevents a comprehensive understanding of these challenges and potential solutions. Nevertheless, addressing these issues can lead to more efficient resource use and reduced environmental impact in the field of biomaterials.

4.
Chem Eng J ; 4712023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39280062

RESUMO

Metal-organic frameworks (MOFs) are a novel class of crystalline porous materials, consisting of metal ions and organic linkers. These hybrid materials possess exceptional porosity and specific surface area, which have recently garnered significant interest due to their potential applications in gas separation and storage, energy storage, biomedical imaging, and drug delivery. As MOFs are being explored for biomedical applications, it is essential to comprehensively assess their toxicity. Although nearly ninety thousand MOFs have been investigated, evaluating and optimizing their physico-chemical properties in relevant biological systems remain critical for their clinical translation. In this review article, we first provide a brief classification of MOFs based on their chemical structures. We then conduct a comprehensive evaluation of in vitro and in vivo studies that assess the biocompatibility of MOFs. Additionally, we discuss various approaches to mitigate the critical factors associated with MOF toxicity. To this end, the effects of chemistry, particle size, morphology, and particle aggregation are examined. To better understand MOFs' potential toxicity to living organisms, we also delve into the toxicity mechanisms of nanoparticles (NPs). Furthermore, we introduce and evaluate strategies such as surface modification to reduce the inherent toxicity of MOFs. Finally, we discuss current challenges, the path to clinical trials, and new research directions.

5.
Materials (Basel) ; 15(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36079326

RESUMO

Alkali-activated binders have the potential to consume various types of waste materials. Low initial molar ratios of SiO2/Al2O3 geopolymer mortars were considered in this article. Here we studied alkali-activated binders produced with photovoltaic glass powder in 5%; kaolin clay in 15%; ground granulated blast furnace slag in 30%; alumina-lime cement in 30%; and, interchangeably, fly ash from coal combustion in 5%, fly ash from biomass combustion in 5%, or granulated autoclaved cellular concrete in 5%. The influence of clay dehydroxylation, curing conditions, glass presence, and a kind of waste material was investigated. According to the experimental results, strength (compressive and tensile) gradually increased with increasing time and with the use of calcined clay. Significant improvement in compressive strength was seen with the additional 3 days curing time in 105 °C when non-sintered clay was used. The presence of photovoltaic glass in alkali-activated mortars immobilised mercury and arsenic but released zinc, chromium, and sulphates. The microscopic observations confirmed the greater densification of the microstructure of the binder made of calcined clay due to its greater surface development and dehydroxylation. The binder of non-calcined clay was granular, and the interfacial transitional zone was more porous. The C-A-S-H gel seemed to be the main phase. XRD examination confirmed the presence of C-A-S-H, C-S-H, zeolites, and many other phases in minor amount. The presented research was a pilot study, and its main goal was to develop it further.

6.
Waste Manag ; 150: 174-184, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35843055

RESUMO

Waste tires management is a serious and global environmental problem. Therefore, searching for low-cost and industrial-scale applicable tire recycling methods is gaining more and more attention. Waste tire rubber is valuable source of secondary raw materialsforthecircular economy and current trends indicate that application of waste rubbers during manufacturing value-added productsshould increase in near future. Sustainable development of rubber devulcanization technologies and appropriate design of cradle-to-cradle loops for rubber goods are the most promising strategies for achieving a higher level of rubber recycling. This work presents the state-of-the-art in the patented waste tire rubber devulcanization technologies including dynamic desulfurization, reactive extrusion, microwave treatment, and also other less popular methods. Special attention was focused on the used components, rubber treatment conditions and static mechanical properties of reclaimed rubbers. Moreover, environmental aspects and limitations related to rubber devulcanization technologies implementation are also discussed. Our findings showed that reclaimed rubbers described in patents are characterized by higher tensile strength and elongation break (depending on devulcanization technology median: 16.6-19.0 MPa and 321-443%, respectively) compared to the literature data (median: 10.3 MPa and 309%) or commercial products (median: 6.8 MPa and 250%). The significant differences observed in performance properties of reclaimed rubbers resulted mainly from devulcanization efficiency related to waste tires composition or source and rubber treatment conditions. Considering environmental and economic aspects, reactive extrusion is the most promising method further development rubber devulcanization technologies.


Assuntos
Reciclagem , Borracha , Micro-Ondas , Tecnologia , Resistência à Tração
7.
Polymers (Basel) ; 14(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35160532

RESUMO

In this paper, low-temperature extrusion of ground tire rubber was performed as a pro-ecological waste tires recycling method. During this process, ground tire rubber was modified with constant content of dicumyl peroxide and a variable amount of elastomer (in the range: 2.5-15 phr). During the studies, three types of elastomers were used: styrene-butadiene rubber, styrene-ethylene/butylene-styrene grafted with maleic anhydride and ethylene-octene copolymer. Energy consumption measurements, curing characteristics, physico-mechanical properties and volatile organic compounds emitted from modified reclaimed GTR were determined. The VOCs emission profile was investigated using a passive sampling technique, miniature emission chambers system and static headspace analysis and subsequently quantitative or qualitative analysis by gas chromatography. The VOCs analysis showed that in the studied conditions the most emitted volatile compounds are dicumyl peroxide decomposition by-products, such as: α-methylstyrene, acetophenone, α-cumyl alcohol, methyl cumyl ether, while the detection level of benzothiazole (devulcanization "marker") was very low. Moreover, it was found that the mechanical properties of the obtained materials significantly improved with a higher content of styrene-butadiene rubber and styrene-ethylene/butylene-styrene grafted with maleic anhydride while the opposite trend was observed for ethylene-octene copolymer content.

8.
Materials (Basel) ; 15(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35160790

RESUMO

In this work, GTR/thermoplastics blends (in ratio 50/50 and 75/25 wt.%) were prepared by melt-compounding in an internal mixer. During research, trans-polyoctenamer rubber (TOR), ethylene-vinyl acetate copolymer (EVA), ethylene-octene copolymer (EOC), and linear low-density polyethylene (LLDPE), were used in their thermoplastic phase. Microstructure and processing-performance property interrelationships of the studied materials were investigated by: atomic force microscopy (AFM), scanning electron microscopy (SEM), rubber process analyzer (RPA), Mooney viscometer, plastometer, gas chromatography with mass spectrometry, differential scanning calorimetry (DSC), tensile tests and swelling behavior. In blends of thermoplastics with a high content of GTR (50 and 75 wt.%), the thermoplastic modifier type had a significant impact on the processing behavior and microstructure of blends. In terms of the physico-mechanical properties, the GTR/thermoplastics ratio affected elongation at break, hardness, and density, while its effect on tensile strength was negligible. DSC analysis showed that thermoplastics, as modifiers of GTR, should be considered as binders and not plasticizers, as reflected in the almost constant glass-transition temperature of the blends. RPA measurements indicated higher values of G* and η* for GTR-rich blends. SEM showed a rubber-like interfacial break, while AFM confirmed interfacial contact between GTR and thermoplastics.

9.
Polymers (Basel) ; 13(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34833313

RESUMO

In this paper, ground tire rubber was modified with dicumyl peroxide and a variable content (in the range of 0-15 phr) of ethylene-vinyl acetate copolymers characterized by different vinyl acetate contents (in the range of 18-39 wt.%). Modification of ground tire rubber was performed via an auto-thermal extrusion process in which heat was generated during internal shearing of the material inside the extruder barrel. The processing, performance properties, and storage stability of modified reclaimed ground tire rubber were evaluated based on specific mechanical energy, infrared camera images, an oscillating disc rheometer, tensile tests, equilibrium swelling, gas chromatography combined with a flame ionization detector, and gas chromatography with mass spectrometry. It was found that the developed formulas of modified GTR allowed the preparation of materials characterized by tensile strengths in the range of 2.6-9.3 MPa and elongation at break in the range of 78-225%. Moreover, the prepared materials showed good storage stability for at least three months and satisfied processability with commercial rubbers (natural rubber, styrene-butadiene rubber).

10.
Int J Mol Sci ; 21(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348897

RESUMO

Mass spectrometry methods are commonly used in the identification of peptides and biomarkers. Due to a relatively low abundance of proteins in biological samples, there is a need for the development of novel derivatization methods that would improve MS detection limits. Hence, novel fluorescent N-hydroxysuccinimide esters of dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium carboxylates (Safirinium P dyes) have been synthesized. The obtained compounds, which incorporate quaternary ammonium salt moieties, easily react with aliphatic amine groups of peptides, both in solution and on the solid support; thus, they can be applied for derivatization as ionization enhancers. Safirinium tagging experiments with ubiquitin hydrolysate revealed that the sequence coverage level was high (ca. 80%), and intensities of signals were enhanced up to 8-fold, which proves the applicability of the proposed tags in the bottom-up approach. The obtained results confirmed that the novel compounds enable the detection of trace amounts of peptides, and fixed positive charge within the tags results in high ionization efficiency. Moreover, Safirinium NHS esters have been utilized as imaging agents for fluorescent labeling and the microscopic visualization of living cells such as E. coli Top10 bacterial strain.


Assuntos
Escherichia coli/química , Ésteres/química , Indicadores e Reagentes/química , Fragmentos de Peptídeos/química , Proteoma/análise , Succinimidas/química , Escherichia coli/metabolismo , Proteoma/química , Espectrometria de Massas por Ionização por Electrospray
11.
J Org Chem ; 82(18): 9737-9743, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28816456

RESUMO

We have used isoxazolo[3,4-b]pyridin-3(1H)-one and isoxazolo[3,4-b]quinolin-3(1H)-one as "masked" heterocyclic hydroxylamines to generate Paal-Knorr intermediates of the Trofimov pyrrole synthesis. The previously inaccessible intermediates, trapped by ethyl propiolate, were obtained by reacting corresponding isoxazolones with 4-fold excess of ethyl propiolate under basic conditions at ambient temperature, and characterized by means of IR and NMR spectroscopic data as well as by single crystal X-ray analysis. Quantum chemical calculations of a [3,3]sigmatropic rearrangement of the N,O-divinyl hydroxylamines to corresponding imino-aldehydes (Paal-Knorr intermediates) revealed that this reaction proceeds via chairlike transition state and is exothermic.

12.
J Sci Food Agric ; 97(4): 1316-1325, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27342385

RESUMO

BACKGROUND: Vodka is a spirit-based beverage made from ethyl alcohol of agricultural origin. At present, increasingly more vodka brands have labels that specify the botanical origin of the product. Until now, the techniques for distinguishing between vodkas of different botanical origin have been costly, time-consuming and insufficient for making a distinction between vodka produced from similar raw materials. Therefore, it is of utmost importance to find a fast and relatively inexpensive technique for conducting such tests. RESULTS: In the present study, we employed comprehensive two-dimensional gas chromatography (GC×GC) and an electronic nose based on the technology of ultra-fast GC with chemometric methods such as partial least square discriminant analysis, discriminant function analysis and soft independent modeling of class analogy. CONCLUSION: Both techniques allow a distinction between the vodkas produced from different raw materials. In the case of GC×GC, the differences between vodkas were more noticeable than in the analysis by electronic nose; however, the electronic nose allowed the significantly faster analysis of vodkas. © 2016 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Cromatografia Gasosa/métodos , Nariz Eletrônico , Odorantes/análise , Plantas/química , Compostos Orgânicos Voláteis/análise , Análise Discriminante , Grão Comestível/química , Rotulagem de Alimentos , Humanos , Análise dos Mínimos Quadrados , Modelos Biológicos , Modelos Estatísticos , Tubérculos/química , Poaceae/química , Análise de Componente Principal , Solanum tuberosum/química , Especificidade da Espécie
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 173: 849-853, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27816884

RESUMO

Headspace mass-spectrometry (HS-MS), mid infrared (MIR) and UV-vis spectroscopy were used to authenticate whisky samples from different origins and ways of production ((Irish, Spanish, Bourbon, Tennessee Whisky and Scotch). The collected spectra were processed with partial least-squares discriminant analysis (PLS-DA) to build the classification models. In all cases the five groups of whiskies were distinguished, but the best results were obtained by HS-MS, which indicates that the biggest differences between different types of whisky are due to their aroma. Differences were also found inside groups, showing that not only raw material is important to discriminate samples but also the way of their production. The methodology is quick, easy and does not require sample preparation.


Assuntos
Bebidas Alcoólicas/análise , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Espectrofotometria Infravermelho/métodos
14.
J Anal Methods Chem ; 2016: 8763436, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446633

RESUMO

Spirit beverages are a diverse group of foodstuffs. They are very often counterfeited which cause the appearance of low quality products or wrongly labelled products on the market. It is important to find a proper quality control and botanical origin method enabling the same time preliminary check of the composition of investigated samples, which was the main goal of this work. For this purpose, the usefulness of electronic nose based on ultra-fast gas chromatography (fast GC e-nose) was verified. A set of 24 samples of raw spirits, 33 samples of vodkas, and 8 samples of whisky were analysed by fast GC e-nose. Four data analysis methods were used. The PCA was applied for the visualization of dataset, observation of the variation inside groups of samples, and selection of variables for the other three statistical methods. The SQC method was utilized to compare the quality of the samples. Both the DFA and SIMCA data analysis methods were used for discrimination of vodka, whisky, and spirits samples. The fast GC e-nose combined with four statistical methods can be used for rapid discrimination of raw spirits, vodkas, and whisky and in the same for preliminary determination of the composition of investigated samples.

15.
Crit Rev Anal Chem ; 45(3): 201-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25849822

RESUMO

Spirit-based beverages are alcoholic drinks; their production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze, and scientists commonly choose gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with various functional groups. This article describes different types of gas chromatography techniques and their most commonly used associated extraction techniques (e.g., LLE, SPME, SPE, SFE, and SBME) and detectors (MS, TOFMS, FID, ECD, NPD, AED, O or EPD). Additionally, brief characteristics of internationally popular spirit-based beverages and application of gas chromatography to the analysis of selected alcoholic drinks are presented.


Assuntos
Bebidas Alcoólicas/análise , Cromatografia Gasosa/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
16.
J Sci Food Agric ; 95(11): 2159-66, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25315338

RESUMO

Whisky (whiskey) is one of the most popular spirit-based drinks made from malted or saccharified grains, which should mature for at least 3 years in wooden barrels. High popularity of products usually causes a potential risk of adulteration. Thus authenticity assessment is one of the key elements of food product marketing. Authentication of whisky is based on comparing the composition of this alcohol with other spirit drinks. The present review summarizes all information about the comparison of whisky and other alcoholic beverages, the identification of type of whisky or the assessment of its quality and finally the authentication of whisky. The article also presents the various techniques used for analyzing whisky, such as gas and liquid chromatography with different types of detectors (FID, AED, UV-Vis), electronic nose, atomic absorption spectroscopy and mass spectrometry. In some cases the application of chemometric methods is also described, namely PCA, DFA, LDA, ANOVA, SIMCA, PNN, k-NN and CA, as well as preparation techniques such SPME or SPE.


Assuntos
Bebidas Alcoólicas/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Rotulagem de Alimentos , Nariz Eletrônico , Etanol/análise , Humanos
17.
J Agric Food Chem ; 62(7): 1423-48, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24506450

RESUMO

Nowadays, consumers are paying great attention to the characteristics of food such as smell, taste, and appearance. This motivates scientists to imitate human senses using devices known as electronic senses. These include electronic noses, electronic tongues, and computer vision. Thanks to the utilization of various sensors and methods of signal analysis, artificial senses are widely applied in food analysis for process monitoring and determining the quality and authenticity of foods. This paper summarizes achievements in the field of artificial senses. It includes a brief history of these systems, descriptions of most commonly used sensors (conductometric, potentiometric, amperometic/voltammetric, impedimetric, colorimetric, piezoelectric), data analysis methods (for example, artificial neural network (ANN), principal component analysis (PCA), model CIE L*a*b*), and application of artificial senses to food analysis, in particular quality control, authenticity and falsification assessment, and monitoring of production processes.


Assuntos
Técnicas Biossensoriais/métodos , Análise de Alimentos/métodos , Técnicas Biossensoriais/instrumentação , Nariz Eletrônico , Análise de Alimentos/instrumentação , Humanos , Olfato , Paladar
18.
Sensors (Basel) ; 13(4): 5008-27, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23591962

RESUMO

The paper presents the potential of an electronic nose technique in the field of fast diagnostics of patients suspected of Chronic Obstructive Pulmonary Disease (COPD). The investigations were performed using a simple electronic nose prototype equipped with a set of six semiconductor sensors manufactured by FIGARO Co. They were aimed at verification of a possibility of differentiation between model reference mixtures with potential COPD markers (N,N-dimethylformamide and N,N-dimethylacetamide). These mixtures contained volatile organic compounds (VOCs) such as acetone, isoprene, carbon disulphide, propan-2-ol, formamide, benzene, toluene, acetonitrile, acetic acid, dimethyl ether, dimethyl sulphide, acrolein, furan, propanol and pyridine, recognized as the components of exhaled air. The model reference mixtures were prepared at three concentration levels-10 ppb, 25 ppb, 50 ppb v/v-of each component, except for the COPD markers. Concentration of the COPD markers in the mixtures was from 0 ppb to 100 ppb v/v. Interpretation of the obtained data employed principal component analysis (PCA). The investigations revealed the usefulness of the electronic device only in the case when the concentration of the COPD markers was twice as high as the concentration of the remaining components of the mixture and for a limited number of basic mixture components.


Assuntos
Biomarcadores/análise , Nariz Eletrônico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Gases/análise , Humanos , Análise de Componente Principal , Padrões de Referência , Processamento de Sinais Assistido por Computador , Volatilização
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