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1.
J Environ Manage ; 342: 118298, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37270983

RESUMO

Ponds occupy a large share of standing water worldwide and play an important role in providing various ecosystem services. There are concerted efforts of the European Union either to create new ponds, or to restore and preserve existing ponds as nature-based solutions to provide benefits to ecosystem and human well-being. As part of the EU PONDERFUL project, selected pondscapes (i.e. landscapes of ponds) in eight different countries - hereafter "demo-sites", are studied to comprehensively understand their characteristics and their efficiency to provide ecosystem services. In addition, the needs and knowledge of stakeholders who own, work, research, or benefit from the pondscapes are also important, because of their capabilities to create, manage and develop the pondscapes. Therefore, we established connection with stakeholders to study their preferences and visions on the pondscapes. Using the analytic hierarchy process, this study shows that in general stakeholders in the European and Turkish demo-sites prefer environmental benefits to economic benefits, while stakeholders in the Uruguayan demo-sites rank the economic benefits higher. More specifically, in the European and Turkish demo-sites, the biodiversity benefits, i.e. life-cycle maintenance, habitat and gene pool protection, receive the highest ranking among all groups. On the other hand, stakeholders at the Uruguayan demo-sites rank provisioning benefits as the most important, because many ponds in Uruguayan demo-sites are being used for agricultural purposes. Understanding those preferences helps policy makers to address the needs of stakeholders more correctly, when considering any action or policy for the pondscapes.


Assuntos
Processo de Hierarquia Analítica , Ecossistema , Humanos , Biodiversidade , Lagoas , Fatores Socioeconômicos , Conservação dos Recursos Naturais
2.
ACS Omega ; 8(14): 12830-12841, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065057

RESUMO

Ethylene propylene diene monomer (EPDM) is one of the most used polymers in the world. It is an elastomer, which means that the existing cross-linking between the main chains of the polymer created during the vulcanization process makes its recycling difficult. In this paper, a possible solution to this issue is studied. The devulcanization of EPDM is achieved by a thermomechanical process followed by microwave irradiation. These combined treatments suppress the cross-linking, yielding a material (EPDMd) that can be successfully blended to form composites. A common elastomer, styrene butadiene rubber (SBR), has been selected as the matrix. The new SBR/EPDMd composites can be useful as elastomeric dielectric materials and can contribute to the recycling of the discarded EPDM. To provide a better understanding of their microstructure and its relationship with their micro- and macroscopic behavior, samples containing 20 and 40% of EPDMd have been tested by thermogravimetric and dielectric analysis, focusing on variables such as the thermal properties of the blends, permittivity, electric modulus, conductivity, and activation energies. The results show interesting changes linked to the presence of EPDMd in the SBR matrix, such as the displacement of the ß dielectric relaxation toward higher frequencies. The correct integration between the two phases is confirmed by the absence of any Maxwell-Wagner-Sillars type relaxation in their dielectric behavior. The presence of additives in the EPDMd samples has an effect on the conductivity, mainly due to the conductive aluminum silicate present in the EPDMd, which acts toward increasing some key dielectric features like conductivity and permittivity and decreasing the insulation of the final SBR/EPDMd materials. The inclusion of EPDMd also affects the α relaxations (low frequencies) and suppresses the ß relaxations (high frequencies). The samples showed a non-Debye dielectric behavior. In short, a compact and well-integrated material with a dielectric behavior is created, which exhibits interesting differences from the reference SBR matrix. Finally, it is concluded that the compounds tested are suitable for applications as electrical insulators.

3.
Materials (Basel) ; 14(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34885476

RESUMO

This article proposes a new model of power supply for mobile low power machines applications, between 10 W and 30 W, such as radio-controlled (RC) electric cars. This power supply is based on general hydrogen from residual aluminum and water with NaOH, so it is proposed energy valorization of aluminum waste. In the present research, a theoretical model allows us to predict the requested aluminum surface and the required flow of hydrogen has been developed, also considering, in addition to the geometry and purity of the material, two key variables as the temperature and the molarity of the alkaline solution used in the hydrogen production process. Focusing on hydrogen production, isopropyl alcohol plays a key role in the reactor's fuel cell vehicle as it filters out NaOH particles and maintains a constant flow of hydrogen for the operation of the machine, keeping the reactor temperature controlled. Finally, a comparison of the theoretical and experimental data has been used to validate the developed model using aluminum sheets from ring cans to generate hydrogen, which will be used as a source of hydrogen in a power fuel cell of an RC car. Finally, the manuscript shows the parts of the vehicle's powertrain, its behavior, and mode of operation.

4.
Polymers (Basel) ; 13(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34641029

RESUMO

Waste from pneumatic wheels is one of the major environmental problems, and the scientific community is looking for methods to recycle this type of waste. In this paper, ground tire rubber particles (GTR) from disused tires have been mixed with samples of low-density polyethylene (LDPE) and high-density polyethylene (HDPE), and morphological tests have been performed using scanning electron microscopy (SEM), as well as the dynamic electric analysis (DEA) dielectric characterization technique using impedance spectroscopy. From this experience, how GTR reinforcement influences polyethylene and what influence GTR particles have on the branched polyethylene has been detected. For pure LDPE samples, a Debye-type dielectric behavior is observed with an imperfect semicircle, which depends on the temperature, as it shows differences for the samples at 30 °C and 120 °C, unlike the HDPE samples, which do not show such a trend. The behavior in samples with Debye behavior is like an almost perfect dipole and is due to the crystalline behavior of polyethylene at high temperature and without any reinforcement. These have been obtained evidence that for branched PE (LPDE) the Maxwell Wagner Sillars (MWS) effect is highly remarkable and that this happens due to the intrachain polarization effect combined with MWS. This means that the permittivity and conductivity at LDPE/50%GTR are high than LDPE/70%GTR. However, it does not always occur that way with HDPE composites in which HDPE/70%GTR has the highest values of permittivity and conductivity, due to the presence of conductive fraction (Carbon Black-30%) in the GTR particles and their dielectric behavior.

5.
Endosc Int Open ; 9(7): E1070-E1076, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34222632

RESUMO

Background and study aims Efficacy and safety of NAAP for gastrointestinal endoscopy have been widely documented, although there is no information about the outcomes of colonoscopy when the endoscopist supervises the sedation. In this context, the aim of this trial was to determine the equivalence of adenoma detection rate (ADR) in colorectal cancer (CRC) screening colonoscopies performed with non-anesthesiologist-administered propofol (NAAP) and performed with monitored anesthesia care (MAC). Patients and methods This was a single-blind, non-randomized controlled equivalence trial that enrolled adults from a national CRC screening program (CRCSP). Patients were blindly assigned to undergo either colonoscopy with NAAP or MAC. The main outcome measure was the ADR in CRCSP colonoscopies performed with NAAP. Results We included 315 patients per group. The median age was 59.76 ±â€Š5.81 years; 40.5 % of patients were women. The cecal intubation rate was 97 %, 81.8 % of patients had adequate bowel preparation, withdrawal time was > 6 minutes in 98.7 %, and the median global exploration time was 24.25 ±â€Š8.86 minutes (range, 8-70 minutes). The ADR was 62.9 % and the complication rate (CR) was 0.6 %. Analysis by intention-to-treat showed an ADR in the NAAP group of 64.13 % compared with 61.59 % in the MAC group, a difference (δADR) of 2.54 %, 95 %CI: -0.10 to 0.05. Analysis by per-protocol showed an ADR in the NAAP group of 62.98 %, compared with 61.94 % in the MAC group, δADR: 1.04 %, 95 %CI: -0.09 to 0.07. There was no difference in CR (NAAP: 0,63 vs. MAC: 0.63); P  = 1.0. Conclusions ADR in colorectal cancer screening colonoscopies performed with NAAP was equivalent to that in those performed with MAC. Similarly, there was no difference in complication rates.

6.
Materials (Basel) ; 13(23)2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33291275

RESUMO

Currently, the huge use of tires generates large quantities of waste material which represents a severe environmental problem. The common technique used for processing waste tires is crushing using mechanical methods and separating tire components like fibers, metals, and rubber from the used tire. The aim of this research is the recycling of this rubber from crushed tires, called ground tire rubber (GTR). With this aim, the manuscript analyses key mechanical properties of the thermoplastic composites produced by blending of crushed and micronized small particles of waste rubber tires with several industrial thermoplastic polymers. These types of composites are defined based on the total amount GTR in percent by weight, in the composite, and also, the particle sizes used in each case, so these aforementioned two variables (microparticle size and amounts) along with seven common industrial polymers define a series of composites for which the mechanical properties were tested, studied, analyzed and finally presented. Finally, the results obtained show that this proposed recycling method could be a way to enhance some specific polymer properties and could contribute to reducing the total of end of life used tire stocks environmental problem.

7.
Polymers (Basel) ; 12(11)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198382

RESUMO

The purpose of the present research is to obtain waste of polymeric composite as an insulator capacitive application. Rubber materials, once they end their useful life, may be difficult to reuse or recycle. At present, research only uses one tire recycling method, which involves grinding and separating steel and fibers from vulcanized rubber, and then using the rubber particles for industrial capacitors. The methodology for this research is to compare the permittivity (ε' and ε″) between high-density polyethylene (HDPE) and the polymer matrix compound, consisting of an HDPE polymeric matrix blended with end-of-life tire particles (ground tire rubber (GTR)), to analyze the feasibility of using such tires as electrically insulating materials (dielectrics). The incorporation of carbon black in the GTR compounds modifies conductivity; GTRs carry a significant amount of carbon black, and therefore some electrical properties may change significantly compared to highly insulating polymer substrates. The performed experimental study is based on a dynamic electric analysis (DEA) test developed in the frequency range of 10-2 Hz to 3 MHz and at different temperatures (from 35 to 70 °C) of different samples type: HDPE neat and HDPE compounds with 10%, 20% and 40% of GTR loads. A sample's electrical behavior is checked for its dependence on frequency and temperature, focused on the permittivity property; this is a key property for capacitive insulators and is key for examining the possible applications in this field, for HDPE + GTR blends. Results for the permittivity behavior and the loss factor show different electrical behavior. For a neat HDPE sample, no dependence with frequency nor temperature is shown. However, with the addition of 10%, 20%, and 40% amount of GTR the HDPE compounds show different behaviors: for low frequencies, interfacial polarization relaxation is seen, due to the Maxwell-Wagner-Sillars (MWS) effect, performed in heterogeneous materials. In order to analyze thermal and morphological properties the differential scanning calorimetry (DSC) test and scanning electron microscopy (SEM) have been used. Results obtained show that adding waste tire particles in an HDPE matrix allows HDPE + 40% GTR blends to act as a dielectric in capacitors, increasing the capacitor dielectric efficiency in the low frequencies due to the MWS effect, which increases the dielectric constant.

8.
Appl Radiat Isot ; 112: 27-30, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26986812

RESUMO

Radioisotope holmium is a candidate to be used in cancer treatment and diagnosis. There are different holmium salts and they present distinct solubility and consequently different biodistribution profiles. In this work, we aimed to evaluate the biodistribution profiles of two holmium salts (chloride and sulfate) and holmium nanoparticles (oxide) through an in vivo biodistribution assay using animal model. Samples were labeled with technetium-99m and administered in Wistar rats by retro-orbital route. Holmium chloride is highly soluble in water and it was quickly filtered by the kidneys while holmium sulfate that presents lower solubility in water was mainly found in the liver and the spleen. However, both the salts showed a similar biodistribution profile. On the other hand, holmium oxide showed a very different biodistribution profile since it seemed to interact with all organs. Due to its particle size range (approximately 100nm) it was not intensively filtered by the kidneys being found in high quantities in many organs, for this reason its use as a nanoradiopharmaceutical could be promising in the oncology field.


Assuntos
Hólmio/farmacocinética , Radioisótopos/farmacocinética , Animais , Hólmio/química , Masculino , Nanopartículas Metálicas/química , Radioisótopos/química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Wistar , Tecnécio/química , Tecnécio/farmacocinética , Distribuição Tecidual
9.
Gastroenterol. hepatol. (Ed. impr.) ; 34(9): 605-610, Nov. 2011.
Artigo em Espanhol | IBECS | ID: ibc-98650

RESUMO

Objetivo Valorar los recursos disponibles en los hospitales comarcales catalanes para la asistencia urgente de la hemorragia digestiva alta. Método Se analiza una encuesta enviada a 32 hospitales, sobre la existencia, composición y recursos del turno de guardia (TDG) de endoscopia, referida al año 2009.ResultadosRespondieron 24 centros, que cubrían la asistencia de 3.954.000 habitantes. Tenían TDG 12 hospitales. No disponían de TDG en su centro de referencia 1.483.000 habitantes. Los centros con TDG tenían más camas y cubrían más población. Los TDG estaban formados por 4,5 endoscopistas (rango 2-11), que cubrían 82,1 (33,2-182,5) guardias/año. Diecisiete centros reportaban 1.571 episodios (51 por centro, rango 3-280, 39,68/100.000 hab.). Los centros con TDG reportaban más casos (76 vs. 43, p=0,047). Los que no disponen de TDG derivaron más pacientes (147 vs. 17, p= 0,001). Los pacientes en urgencias estaban a cargo de medicina interna en 4 centros, de cirugía en 14 y repartidos entre ambos servicios en 6. Si ingresaban, quedaron a cargo de Digestivo solo en 6 hospitales. Los recursos más utilizados eran la ligadura en la hemorragia varicosa y las terapias de inyección en la no varicosa. Un 21% de centros no realizaban tratamiento combinado. Conclusiones Una proporción significativa de la población no dispone de endoscopista de guardia en su centro de referencia. La constitución de TDG en hospitales comarcales supone importantes cargas asistenciales. La coordinación entre profesionales y centros permitiría la aplicación eficiente de los recursos terapéuticos y el establecimiento de TDG en centros que no tienen (AU)


Objective To evaluate the resources available in Catalan regional hospitals for the emergency care of upper gastrointestinal hemorrhage. Methods We analyzed a survey sent to 32 hospitals on the availability, composition and resources of a duty endoscopy service for the year 2009.ResultsResponses were obtained from 24 centers, covering 3,954,000 inhabitants. Duty endoscopists were available in 12 hospitals. A total of 1,483,000 inhabitants were unable to access a duty endoscopist in the referral center. Centers with duty endoscopists had more beds and had a larger catchment area. Duty services were composed of 4.5 endoscopists (range 2-11), covering 82.1 (33.2-182.5) duty shifts/year. Seventeen centers reported 1,571 episodes (51%, range: 3-280, 39.68/100,000 inhabitants). Centers with a duty service reported a greater number of cases (76 vs. 43, p=0.047). Centers without this service referred a greater number of patients (147 vs. 17, p=0.001). Patients in the emergency department were under the care of the internal medicine department in four centers, the surgery department in 14 centers and under the care of both departments in six. Admitted patients were under the care of the gastroenterology department in only six hospitals. The most widely used procedures were ligation of varicose bleeding and injection therapies in non-varicose bleeding. Twenty-one percent of centers did not perform combined treatment. Conclusions A significant proportion of the population does not have access to a duty endoscopist in referral centers. Duty shifts represent significant workload in regional hospitals. Coordination among health professionals and centers would allow the efficient application of therapeutic resources and a duty endoscopy service to be established in centers lacking this resource (AU)


Assuntos
Humanos , Serviços Médicos de Emergência/estatística & dados numéricos , Tratamento de Emergência/métodos , Hemorragia Gastrointestinal/epidemiologia , Endoscopia Gastrointestinal , Úlcera Péptica Hemorrágica/epidemiologia , Hemostase Endoscópica , Varizes Esofágicas e Gástricas/epidemiologia , Inibidores da Bomba de Prótons/uso terapêutico , Vasoconstritores/uso terapêutico
10.
Gastroenterol Hepatol ; 34(9): 605-10, 2011 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-22000030

RESUMO

OBJECTIVE: To evaluate the resources available in Catalan regional hospitals for the emergency care of upper gastrointestinal hemorrhage. METHODS: We analyzed a survey sent to 32 hospitals on the availability, composition and resources of a duty endoscopy service for the year 2009. RESULTS: Responses were obtained from 24 centers, covering 3,954,000 inhabitants. Duty endoscopists were available in 12 hospitals. A total of 1,483,000 inhabitants were unable to access a duty endoscopist in the referral center. Centers with duty endoscopists had more beds and had a larger catchment area. Duty services were composed of 4.5 endoscopists (range 2-11), covering 82.1 (33.2-182.5) duty shifts/year. Seventeen centers reported 1,571 episodes (51%, range: 3-280, 39.68/100,000 inhabitants). Centers with a duty service reported a greater number of cases (76 vs. 43, p=0.047). Centers without this service referred a greater number of patients (147 vs. 17, p=0.001). Patients in the emergency department were under the care of the internal medicine department in four centers, the surgery department in 14 centers and under the care of both departments in six. Admitted patients were under the care of the gastroenterology department in only six hospitals. The most widely used procedures were ligation of varicose bleeding and injection therapies in non-varicose bleeding. Twenty-one percent of centers did not perform combined treatment. CONCLUSIONS: A significant proportion of the population does not have access to a duty endoscopist in referral centers. Duty shifts represent significant workload in regional hospitals. Coordination among health professionals and centers would allow the efficient application of therapeutic resources and a duty endoscopy service to be established in centers lacking this resource.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Hemorragia Gastrointestinal , Hemorragia Gastrointestinal/terapia , Hospitais/estatística & dados numéricos , Humanos , Estudos Retrospectivos , Espanha
11.
Metas enferm ; 14(5): 26-30, jun. 2011. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-91356

RESUMO

Objetivo: determinar el impacto de la presencia de los padres durante larealización de técnicas de Enfermería a su hijo, sobre el nivel de miedodel menor; estudiar la variabilidad de dicho miedo en diferentes edadesinfantiles y entre la presencia de los padres y el número de intentos necesariospara realizar la técnica.Material y método: estudio observacional analítico de cohorte prospectivoen el servicio de urgencias del Hospital de Figueres (Girona), sobreniños/as de un mes a 12 años a los que se practicaban técnicas de Enfermería,30 expuestos a la presencia de los padres y 27 no. El nivel demiedo manifestado durante la técnica se midió a través del resultadoNOC Nivel de miedo 1210. Otras variables de estudio: edad, sexo, tipode técnica realizada, intentos necesarios para realizar la técnica y motivode consulta. Se utilizaron pruebas no paramétricas de contraste dehipótesis (test de U de Mann-Whitney test de Wilcoxon).Resultados: los niños de 0-6 años experimentaron miedo frente a lastécnicas de Enfermería. La presencia de los padres no redujo de maneraestadísticamente significativa el miedo ante las técnicas. Tampocoexistía relación entre la presencia de los padres y el número de intentosnecesarios por parte del profesional enfermero para realizar la técnica.Conclusiones: los niños de 0-6 años experimentan miedo durante losprocedimientos enfermeros, no siendo así en los de 6-12 años. No se demuestrarelación entre la presencia de los padres y el miedo a que experimentanlos niños ante técnicas de Enfermería. Tampoco se evidenciaasocación entre el número de intentos necesarios para realizar latécnica y la presencia de los progenitores, hecho que puede ayudar a reducirel estrés del equipo de Enfermería, favoreciendo el vínculo padres-hijos y la relación de éstos con el profesional de la salud (AU)


Objective: to assess the impact of the parent’s presence on their childrenwhile they undergo nursing techniques, to determine the level of fear ofthe minor, to assess the variability of this fear at different child ages andbetween the presence of the parents and the number of attempts tocomplete the technique.Materials and methods: analytical prospective observational cohortstudy at the emergency service of the Figueres hospital (Girona), on boysand girls aged 1 month to 12 years who underwent nursing techniques. 30were exposed to the parent’s presence and 27 were not. The level of fearmanifested during the technique was measured through the 2010 NOCLevel of Fear. Other study variables included: age, gender, type of techniqueperformed on the child, attempts needed to perform the techniqueand motive for consultation (Mann-Whitney t test and Wilcoxon test).Results: children aged 0-6 years experienced fear when subjected tonursing techniques. The presence of the parents did not significantly reducefear to the techniques. No relationship was found either betweenthe presence of the parents and the amount of attempts needed to performthe technique by the nursing professional.Conclusions: children aged 0-6 years experienced fear to nursing procedures,that not being the case for children aged 6-12 years. No relationshipis found between the presence of the parents and the fear experiencedby children to nursing techniques. There is also no evidenceon the association between the number of attempts needed to completethe technique and the presence of the parents, a fact that might help reducethe stress of the nursing team thus favouring the link betweenparent-child and their relationship with the healthcare professional (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Medo/psicologia , Cuidados de Enfermagem/psicologia , Serviços de Saúde da Criança , Relações Pais-Filho , Enfermagem Pediátrica/tendências
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