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1.
Int Orthop ; 44(8): 1453-1459, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32591960

RESUMO

BACKGROUND: From February 21, the day of hospitalisation in ICU of the first diagnosed case of Covid-19, the social situation and the hospitals' organisation throughout Italy dramatically changed. METHODS: The CIO (Club Italiano dell'Osteosintesi) is an Italian society devoted to the study of traumatology that counts members spread in public and private hospitals throughout the country. Fifteen members of the CIO, Chairmen of 15 Orthopaedic and Trauma Units of level 1 or 2 trauma centres in Italy, have been involved in the study. They were asked to record data about surgical, outpatients clinics and ER activity from the 23rd of February to the 4th of April 2020. The data collected were compared with the data of the same timeframe of the previous year (2019). RESULTS: Comparing with last year, overall outpatient activity reduced up to 75%, overall Emergency Room (ER) trauma consultations up to 71%, elective surgical activity reduced up to 100% within two weeks and trauma surgery excluding femoral neck fractures up to 50%. The surgical treatment of femoral neck fractures showed a stable reduction from 15 to 20% without a significant variation during the timeframe. CONCLUSIONS: Covid-19 outbreak showed a tremendous impact on all orthopaedic trauma activities throughout the country except for the surgical treatment of femoral neck fractures, which, although reduced, did not change in percentage within the analysed timeframe.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Procedimentos Ortopédicos/estatística & dados numéricos , Pandemias , Pneumonia Viral , COVID-19 , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Serviço Hospitalar de Emergência , Humanos , Itália/epidemiologia , Ortopedia , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Centros de Traumatologia , Traumatologia
2.
Molecules ; 24(19)2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31569664

RESUMO

The preparation and characterization of innovative organic-inorganic hybrid geopolymers, obtained by valorizing coal fly ash generated from thermoelectric power plants, is reported for the first time. These hybrid materials are prepared by simultaneously reacting fly ash and dimethylsiloxane oligomers at 25 °C in a strongly alkaline environment. Despite their lower density, the obtained materials are characterized by highly improved mechanical properties when compared to the unmodified geopolymer obtained without the use of polysiloxanes, hence confirming the effectiveness of the applied synthetic strategy which specifically aims at obtaining hybrid materials with better mechanical properties in respect to conventional ones. This study is an example of the production of new materials by reusing and valorizing waste raw resources and by-products, thus representing a possible contribution towards the circular economy.


Assuntos
Cinza de Carvão/química , Polímeros/química , Siloxanas/química , Fenômenos Mecânicos , Microscopia Eletrônica de Varredura , Estrutura Molecular , Análise Espectral
3.
J Foot Ankle Surg ; 57(5): 894-898, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29914730

RESUMO

The aim of our study was to investigate which technique among hybrid external fixation, plate and screws, and intramedullary nailing produces better outcomes in foot loading when treating type 43.A1, 43.A2, and 43.A3 fractures, according to the AO classification. From November 2011 to December 2014, 34 patients, including 25 (73.5%) males and 9 (26.5%) females with an average age of 32.3 (range 16 to 67) years, with a type A tibia fracture were treated with intramedullary nailing, plate and screws, or hybrid external fixation. The patients were divided into 3 groups: 16 (47%) received hybrid external fixation, 10 (29.4%) received plate and screw fixation, and 8 (23.5%) received intramedullary nailing fixation. The follow-up protocol included clinical and radiologic evaluations performed at 15 days, 1 month, 3 months, 6 months, and 12 months after surgery. The selected outcome parameters for the 3 groups were as follows: visual analog scale for pain of the traumatized tibia, interval from surgery to weightbearing, average time required for fracture recovery, subjective and objective Ovadia-Beals scores, baropodometric examination at 12 months, walking recovery at 12 months, outcomes, and surgical complications. The endpoint assessment was set at 12 months. The results showed that incorrect reduction of a type A tibia fracture can lead to changes in the sagittal balance line for foot loading and pace training. In conclusion, these findings have shown that the experience of the surgeon in the reduction of the fracture and knowledge of the method of synthesis is essential.


Assuntos
Fixação Intramedular de Fraturas , Fraturas da Tíbia/fisiopatologia , Fraturas da Tíbia/cirurgia , Adolescente , Adulto , Idoso , Placas Ósseas , Parafusos Ósseos , Fixadores Externos , Feminino , Consolidação da Fratura , Análise da Marcha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Suporte de Carga/fisiologia , Adulto Jovem
4.
Int J Mol Sci ; 14(9): 18200-14, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24013372

RESUMO

A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I) or by adding a silane derivative (resin II). The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials.


Assuntos
Resinas Epóxi/síntese química , Triazinas/química , Resinas Epóxi/química
5.
Materials (Basel) ; 16(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36984279

RESUMO

Stabilization/solidification (S/S) is becoming increasingly important, as it allows the remediation of contaminated sediments and their recovery into materials for civil engineering. This research proposes a cement-free cold granulation process for manufactured low-cost aggregates from marine sediments contaminated with organic compounds and metals. After the chemo-physical characterization of the study materials, two mix designs were prepared in a rotary plate granulator by adding two industrial by-products as geopolymer precursors, coal fly ash (CFA) and Blast Furnace Slag (BFS), but also alkaline activation solutions, water, and a fluidizer. The results indicated that sediments treated with mix 1 (i.e., with a higher percentage of water and fluidifier) represent the optimal solution in terms of metal leachability. The metal leachability was strictly influenced by aggregates' porosity, density, and microstructure. The technical performance (such as the aggregate impact value > 30%) suggested the use of granules as lightweight aggregates for pavement construction. The results indicated that cold granulation represents a sustainable solution to recycling contaminated marine sediments, CFA, and BFS into lightweight artificial aggregates.

6.
Materials (Basel) ; 15(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500096

RESUMO

This contribution presents the preparation and characterization of new geopolymer-based mortars obtained from recycling waste deriving from the production process and the "end-of-life" of porcelain stoneware products. Structural, morphological, and mechanical studies carried out on different kinds of mortars prepared by using several types of by-products (i.e., pressed burnt and extruded ceramic waste, raw pressed and gypsum resulting from exhausted moulds) point out that these systems can be easily cast, also in complex shapes, and show a more consistent microstructure with respect to the geopolymer paste, with a reduced amount of microcracks. Moreover, the excellent adhesion of these materials to common substrates such as pottery and earthenware, even for an elevated concentration of filler, suggests their use in the field of technical-artistic value-added applications, such as restoration, conservation, and/or rehabilitation of historic monuments, or simply as materials for building revetments. For all these reasons, the proposed materials could represent valuable candidates to try to overcome some problems experienced in the cultural heritage sector concerning the selection of environmentally friendly materials that simultaneously meet art and design technical requirements.

7.
Materials (Basel) ; 15(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35454421

RESUMO

The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of "green" concrete but that the sustainability of the building materials can only be achieved by implementing simultaneous multiple strategies aimed at reducing environmental impact and improving both durability and performances.

8.
Materials (Basel) ; 14(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467622

RESUMO

Power plants based on solar energy are spreading to accomplish the incoming green energy transition. Besides, affordable high-temperature sensible heat thermal energy storage (SHTES) is required. In this work, the temperature distribution and thermal performance of novel solid media for SHTES are investigated by finite element method (FEM) modelling. A geopolymer, with/without fibre reinforcement, is simulated during a transient charging/discharging cycle. A life cycle assessment (LCA) analysis is also carried out to investigate the environmental impact and sustainability of the proposed materials, analysing the embodied energy, the transport, and the production process. A Multi-Criteria Decision Making (MCDM) with the Analytical Hierarchy Process (AHP) approach, taking into account thermal/environmental performance, is used to select the most suitable material. The results show that the localized reinforcement with fibres increases thermal storage performance, depending on the type of fibre, creating curvatures in the temperature profile and accelerating the charge/discharge. High-strength, high-conductivity carbon fibres performed well, and the simulation approach can be applied to any fibre arrangement/material. On the contrary, the benefit of the fibres is not straightforward according to the three different scenarios developed for the LCA and MCDM analyses, due to the high impact of the fibre production processes. More investigations are needed to balance and optimize the coupling of the fibre material and the solid medium to obtain high thermal performance and low impacts.

9.
Materials (Basel) ; 14(8)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921708

RESUMO

In the last 20 years, there have been a series of seismic events in Italy that have caused serious damage to civil and building structures. This has led to a significant increase in the use of concrete for the reconstruction of new structures and the repair of existing structures damaged by earthquakes. At the same time, the concrete industry is responsible for the most significant environmental damage during the life cycle of the built environment. The environmental disadvantages characterizing the concrete industry are related to the constant growth of the exploitation of natural aggregates. Therefore, it is necessary to use alternative and innovative aggregates that provide good concrete performance and lower environmental impacts. In this study, a very promising route from an environmental point of view is given by the use of artificial aggregates from industrial waste as substitutes for natural aggregates. An innovative low cost and energy saving granulation process has been employed to produce lightweight aggregates using fly ash from the incineration of municipal solid waste and ground granulated blast furnace slag. The final aim of this research is to demonstrate the environmental sustainability of artificial aggregates, through a comparison of three different mixtures.

10.
G Ital Med Lav Ergon ; 32(3 Suppl B): B50-7, 2010.
Artigo em Italiano | MEDLINE | ID: mdl-21302525

RESUMO

INTRODUCTION: In the present paper we investigate the factor structure of the Italian version of the Children's Depression Scales (CDS). METHODS: We analyzed the responses at the questionnaires of 592 subjects (9-16 years old) and we studied three factor structures previous considered in literature. As a first step, we replicated an exploratory factor analyses and, then, a two and three-factor solutions analyzed by a confirmatory factorial analysis. Finally, we modified the models introducing the parameter estimation of correlation between errors when paired item were present (e.g., two similar item but one referred to mother and the other one to father). Results showed the two-factor model interpretation has to be preferred when we administer the CDS Italian version; indeed there are important differences in the factor structure between the Italian and the original English version. CONCLUSIONS: Findings should be considered for further studies on the factor structure of the CDS. Finally, it seems to us not easy to consider these results entirely coherent with Lang & Tisher theory both for how they define the latent trait (i.e., depression), and how they measure it using the CDS.


Assuntos
Depressão/diagnóstico , Inquéritos e Questionários , Adolescente , Criança , Feminino , Humanos , Itália , Masculino
11.
J Clin Orthop Trauma ; 11(Suppl 5): S772-S778, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32999554

RESUMO

BACKGROUND: The number of periprosthetic joint infections (PJI) is continuously increasing because of the increasing number of arthroprostheses performed every year. Two-stage revision, using antibiotic-loaded spacers, remains the gold standard for their treatment. The aim of our study is to compare the use of preformed vs hand-made spacers in hip arthroplasty infections evaluating infection eradication, bone loss and clinical/functional outcomes. METHODS: From January 2010 to December 2017 we performed a prospective nonrandomized study. We pooled 50 patients affected by infected hip joint replacements, and divided them in 2 groups, one receiving commercially preformed spacers and the other receiving hand-made spacers. The study endpoint was set at 12 months. Intra-operative and peri-operative complications, Harris Hip Score (HHS), Short Form 12 Health Survey, intra-operative and radiological evaluation of bone loss were collected. Data were analyzed using descriptive statistics, T-test and Fisher Exact test. RESULTS: We found a statistically significant differences (p < 0.05) between the two groups in favour of the VancogenX group for the following variables: surgical time, first and second stage intraoperative complication rates, infection eradication. Moreover, the preformed-spacers group had better results in the preservation of bone stock, even though the difference was not statistically significant (p > 0.05). CONCLUSION: Our results support the use of preformed antibiotic spacers, even though more studies are needed.

12.
Materials (Basel) ; 13(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991550

RESUMO

Entropy-Stabilized Oxides (ESO) is a modern class of multicomponent advanced ceramic materials with attractive functional properties. Through a five-component oxide formulation, the configurational entropy is used to drive the phase stabilization over a reversible solid-state transformation from a multiphase to a single-phase state. In this paper, a new transition metal/rare earth entropy-stabilized oxide, with composition Ce0.2Zr0.2Y0.2Gd0.2La0.2O2-, was found after several investigations on alternative candidate systems. X-Ray Diffraction (XRD) analyses of calcined powders pointed out different behavior as a function of the composition and a single-phase fluorite structure was obtained after a specific thermal treatment at 1500 °C. Powders presented the absence of agglomeration, so that the sintered specimen exhibited sufficient densification with a small porosity, uniformly distributed in the sample.

13.
Materials (Basel) ; 13(13)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610547

RESUMO

This research investigates the preparation and characterization of new organic-inorganic geopolymeric foams obtained by simultaneously reacting coal fly ash and an alkali silicate solution with polysiloxane oligomers. Foaming was realized in situ using Si0 as a blowing agent. Samples with density ranging from 0.3 to 0.7 g/cm3 that show good mechanical properties (with compressive strength up to ≈5 MPa for a density of 0.7 g/cm3) along with thermal performances (λ = 0.145 ± 0.001 W/m·K for the foamed sample with density 0.330 g/cm3) comparable to commercial lightweight materials used in the field of thermal insulation were prepared. Since these foams were obtained by valorizing waste byproducts, they could be considered as low environmental impact materials and, hence, with promising perspectives towards the circular economy.

14.
Materials (Basel) ; 12(24)2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31817858

RESUMO

For the first time, hybrid organic-inorganic geopolymeric foams were successfully used as monolithic adsorbents for the removal of metallic ions pollutants from wastewaters. The foams were realized by the in situ foaming of a hybrid geopolymer obtained by a reaction of metakaolin and polysiloxane oligomers under strong alkaline conditions and then cured at room temperature. In this way, porous materials with densities ranging from 0.4 to 0.7 g/cm3 and showing good mechanical properties were produced. With the aim of producing self-standing monolithic adsorbents for the removal of metallic ions pollutants from wastewaters, these porous hybrid geopolymers were subjected to a washing pretreatment with ultrapure water, dried, and then used for absorption tests by dipping them into an aqueous solution with an initial concentration of 20 ppm of Pb2+, Cd2+, Cu2+, and Zn2+ ions. Preliminary results indicated that all the tested materials are effective in the adsorption of the tested metal ions and do not release the removed metal ions upon sinking in ultrapure water, even for a very long time. Interestingly, compressive strength tests performed before and after the washing treatments show that the foamed samples remain intact and maintain their physical-mechanical characteristics, suggesting that these kinds of materials are promising candidates for the production of self-standing, monolithic adsorbent substrates that can be easily collected when exhausted, which is a major advantage in comparison with the use of powdered adsorbents. Moreover, since these materials can be obtained by a simple and versatile experimental procedure, they could be easily shaped or directly foamed into precast molds to be used in packed beds as membranes.

15.
Materials (Basel) ; 12(13)2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31252523

RESUMO

The rare-earth carbonates represent a class of materials with great research interest owing to their intrinsic properties and because they can be used as template materials for the formation of other rare earth phases, particularly of rare-earth oxides. However, most of the literature is focused on the synthesis and characterization of hydroxycarbonates. Conversely, in the present study we have synthesized both rare-earth carbonates-with the chemical formula RE2(CO3)3·2-3H2O, in which RE represents a generic rare-earth element, and a tengerite-type structure with a peculiar morphology-and rare-earth hydroxycarbonates with the chemical formula RECO3OH, by hydrothermal treatment at low temperature (120 °C), using metal nitrates and ammonium carbonates as raw materials, and without using any additive or template. We found that the nature of the rare-earth used plays a crucial role in relation to the formed phases, as predicted by the contraction law of lanthanides. In particular, the hydrothermal synthesis of rare-earth carbonates with a tengerite-type structure was obtained for the lanthanides from neodymium to erbium. A possible explanation of the different behaviors of lighter and heavier rare-earths is given.

16.
Chemosphere ; 70(6): 1068-76, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17892893

RESUMO

This paper deals with the application of mechanochemistry to model systems composed of alumina or silica artificially contaminated with n-C16H34. The mechanochemical treatment was carried out by means of a ring mill for times ranging from 10 to 40h. Thermogravimetry and infrared and nuclear magnetic resonance spectroscopies were used for the characterization of the mechanochemical products. The results have indicated that, in the case of alumina, almost all the contaminant n-C16H34 undergoes a complex oxidative reaction path whose end products are strongly held on the surface. These end products are most likely made of crosslinked, partially oxidized hydrocarbon chains bond to the solid surface via COO(-) groups. In the case of silica, the hydrocarbon undergoes a different, equally complex reaction path, but to a lower extent. In this case the end products are most probably carbonylic compounds and graphitic carbon. Then, for both solid matrices, the mechanochemical treatment promotes significant modification of the chemical nature of the polluting hydrocarbon with end products much more difficult to remove from the surface. As the systems studied are models of sites contaminated by aliphatic hydrocarbon, the results are worthy of consideration in relation to the mobility of the contaminants in the environment.


Assuntos
Óxido de Alumínio/química , Hidrocarbonetos/química , Espectroscopia de Ressonância Magnética/instrumentação , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Reprodutibilidade dos Testes
17.
J Hazard Mater ; 157(2-3): 599-604, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18289785

RESUMO

Fuel oil fly ash has been tested as low-cost carbon-based adsorbent of 2-chlorophenol (CP), 2-chloroaniline (CA) and methylene blue (MB) from aqueous solutions. In all the cases the adsorption was found to be of cooperative type. Different adsorption capacities were found for the three organics. Specifically, it was highest for 2-chlorophenol, reaching about 70 mg g(-1), and quite lower in the other two cases, that is about 47 and 36 mg g(-1) for methylene blue and 2-chloroaniline, respectively. Varying the initial pH and adding KCl were found to have different effects on the adsorption of the three organics. In particular, the presence of other ions had no effect on the adsorption of methylene blue, adverse effect in the case of 2-chlorophenol and enhancing effect in the case of 2-chloroaniline.


Assuntos
Compostos de Anilina/isolamento & purificação , Carbono , Clorofenóis/isolamento & purificação , Azul de Metileno/isolamento & purificação , Material Particulado , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Compostos de Anilina/química , Clorofenóis/química , Cinza de Carvão , Resíduos Industriais , Azul de Metileno/química , Tamanho da Partícula , Poluentes Químicos da Água/química
18.
Psychol Rep ; 102(1): 305-11, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18481691

RESUMO

The aim was to investigate the psychometric properties of a proposed experimental version of the 1979 Italian adaptation of the Clinical Depression Questionnaire (Krug & Laughlin, 1976). This version is composed of an increased number of choice alternatives (5 instead of 3), tested with 240 Italian undergraduates. An exploratory item-factor analysis yielded one factor, which accounted for 28.2% of the variance. Analysis of the relationship between this version and an experimental one in 2002 of the 1979 Italian edition of the Anxiety Scale Questionnaire showed the corrective factor was not effective in increasing the discriminative power of the questionnaire for anxiety.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/etnologia , Estudantes , Inquéritos e Questionários , Adulto , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Psicometria
19.
Psychol Rep ; 103(3): 715-26, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19320205

RESUMO

An experimental version of the Italian Junior Eysenck Personality Questionnaire with a 5-point scale was administered to a group of 1,000 high school students, 200 within each age group from 11 to 15 years. Following a previous exploratory factor analysis, which yielded a fourth factor in addition to the original three, the aim of the present research was to study the factor structure of the Italian version using confirmatory factor analysis. Three models were tested, a three-factor orthogonal model, a three-factor oblique model, and a four-factor model based on an a priori separation of extraversion items into two sets. None of the considered models converged satisfactorily. An interpretation of the results was proposed.


Assuntos
Comparação Transcultural , Inventário de Personalidade/estatística & dados numéricos , Adolescente , Criança , Comportamento Exploratório , Extroversão Psicológica , Análise Fatorial , Feminino , Humanos , Comportamento Impulsivo/psicologia , Introversão Psicológica , Itália , Masculino , Transtornos Neuróticos/psicologia , Psicometria/estatística & dados numéricos , Transtornos Psicóticos/psicologia , Valores de Referência , Reprodutibilidade dos Testes , Estudantes/psicologia
20.
Sci Total Environ ; 615: 1506-1517, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29055592

RESUMO

Concrete industry is responsible of the most significant contribution to the global warming due to the large amount of substances with environmental impacts produced during its entire life cycle (production process, construction, maintenance, dismantlement, and scrapping). The most important issue characterizing the concrete industry is related to the constant growth of consumption of natural aggregates. The purpose of the present research is to apply the standard protocol of life cycle assessment to 3 different concrete mixtures composed by wastes from construction and demolition (C&D), marble sludge and cement kiln dust (CDK) in order to compare the environmental and energy impacts. The main purpose is to analyze the potentials (capabilities/benefits) of recycled aggregate concrete. The proposed model analyses 37 recovery possible scenarios. The results were analyzed with the software SimaPro© and with the life cycle impact assessment method Eco Indicator 99. The results show how it is possible to decide for the optimal solution in order to reduce emissions and impacts due to the concrete production.

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