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1.
J Pers Assess ; : 1-16, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885434

RESUMO

The goal was to create a brief temperament inventory grounded in the Regulative Theory of Temperament (FCB-TMI-CC), with a user-friendly, online applicability for studies in different cultures. As the regulative role of temperament is strongly revealed under meaningful stress, the study was planned within the time of the COVID-19 pandemic. To ensure high diversity in terms of culture, economic and environmental conditions, data from nine countries (Poland, United States of America, Italy, Japan, Argentina, South Korea, Ireland, United Kingdom and Kazakhstan) were utilized (min. N = 200 per country). Validation data were gathered on the level of COVID-19 stressors, posttraumatic stress disorder (PTSD), depression, anxiety and stress symptoms, and Big Five personality traits. Multigroup confirmatory factor analysis served as the basis for the inventory's construction. The final culture-common version includes 37 items (5-6 in each of the 7 scales) and covers the core aspects of temperament dimensions. Temperament structure was confirmed to be equivalent across measured cultures. The measurement is invariant at the level of factor loadings and the reliability (internal consistency) and theoretical validity of the scales were at least acceptable. Therefore, the FCB-TMI-CC may serve as a valuable tool for studying temperament across diverse cultures and facilitate cross-cultural comparisons.

2.
Nanotechnology ; 30(39): 394004, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31234154

RESUMO

Herein, a surfactant-free, ethylene glycol-mediated synthesis of PtIr nanoalloys was optimized. In particular, a post-synthesis treatment was identified as the key step in order to determine the nanoparticles size and their organization in the nanostructure, depending on the presence of a reducing agent and on pressure conditions. After synthesis, the as-obtained nanomaterials were broadly characterized: SEM and TEM images, EDX maps and XRD spectra showed the formation of nanorods with a few nanometers size and similar quantitative compositions of platinum and iridium. Afterward, the electrocatalytic activity towards the methanol oxidation reaction of the synthesized nanomaterials was tested and the best sample, treated under a hydrogen/nitrogen flow at 10 bar, exhibits a negligible onset potential (0.058 V) and a very high If/Ib ratio (2.5). Moreover, the aforementioned sample was tested as an electrochemical sensor for the detection of small traces of ammonia in an aqueous solution with a limit of detection of 4.88 µM. The sensor was tested also in simulated wastewater coming from the fertilizer industry, showing proper operation and excellent selectivity.

3.
J Nanosci Nanotechnol ; 18(2): 1176-1185, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448554

RESUMO

Decoration with silver nanoparticles was obtained by coating graphene with a polydopamine layer, able to induce spontaneous metallic nanoparticles formation without any specific chemical interfacial modifier, neither using complex instrumentation. The choice of dopamine was inspired by the composition of adhesive proteins in mussels, related to their robust attach to solid surfaces. The synthesis procedure started from graphite and involved eco-friendly compounds, such as Vitamin C and glucose as reducing agent and water as reaction medium. Silver decorated graphene was inserted as secondary nanofiller in the formulation of a reference conductive adhesive based on epoxy resin and silver flakes. A wide characterization of the intermediate materials obtained along the step procedure for the adhesive preparation was carried out by several techniques. We have found that the presence of nanofiller yields, in addition to an improvement of the thermal conductivity (up to 7.6 W/m · K), a dramatic enhancement of the electrical conductivity of the adhesive. In particular, starting from 3 · 102 S/cm of the reference adhesive, we obtained a value of 4 · 104 S/cm at a nanofiller concentration of 11.5 wt%. The combined double filler conductivity was evaluated by Zallen's model. The effect of the temperature on the resistivity of the adhesive has been also studied.

4.
Nanotechnology ; 28(21): 214003, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28383289

RESUMO

A Tafel slope of 40 mV dec-1 and a very small overpotential were measured for our NiSMoS2G nanocatalyst, prepared using a scalable approach, and consisting of NiS nanoparticles covered by a stabilizing coating of MoS2 nanosheets, on unsophisticated and easy to obtain physical exfoliated graphite. A careful study proves that it is possible to improve the Tafel slope and the overpotential through the optimization of amounts of the different components. The conductive nanocarbon network, the highly active to charge accumulation of NiS nanoparticles and the coupling with MoS2 nanosheets, exposing a large number of edges, result in a very high hydrogen production rate of 1.63 ml cm-2 h-1 at -0.12 V, measured by means of an on-line mass spectrometry analysis.

5.
Nanotechnology ; 28(20): 204001, 2017 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-28319034

RESUMO

Energy density, safety, and simple and environmentally friendly preparation methods are very significant aspects in the realization of a compact supercapacitor. Herein we report the use of a supercritical CO2-assisted gel drying process (SC-CO2) for the preparation of porous electrodes containing dispersed graphene in a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) binder membrane to sandwich in a new portable supercapacitor based on graphene oxide (GO). A GO loading of 60 wt.% was found to give the best combination of factors (porosity, wettability, mechanical and electrochemical properties). Cycling voltammetry and charge/discharge studies showed an excellent capacitance behaviour and stability in an ionic liquid electrolyte, suggesting SC-CO2 processing as a promising platform to produce highly bulky and porous films for supercapacitors. The supercapacitor device delivers a very high energy density of 79.2 Wh kg-1 at a power density of 0.23 KW kg-1 (current density 0.5 A g-1, specific capacitance 36.2 F g-1) while that of steel remains at 50.3 Wh kg-1 at a power density of 2.8 KW kg-1 (current density 6 A g-1, specific capacitance 23.5 F g-1).

6.
J Craniofac Surg ; 27(7): e693-e695, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27564069

RESUMO

Aesthetic of the face is greatly changed in relation to common standards of the past. Modern concepts of beauty from popular models of beautiful faces to actors show a biprotrusive asset with high tension for soft tissues. Facial symmetry has been proposed as a marker of developmental stability that may be important in human mate choice. Any deviation from perfect symmetry can be considered a reflection of imperfect development. The goal of maxillofacial surgery should be to give the best results for both aesthetic and functional aspects. Following these new concepts of aesthetic of the face, new surgical procedure by osteodistraction techniques will lead to a very natural final result by harmonizing the face. The aim of this study was to detect aesthetic results on 10 patients operated for skeletal discrepancies by maxillary distraction and jaw repositioning compared with other 10 patients operated by conventional techniques on a 5-point scale by Likert.


Assuntos
Beleza , Estética , Face/cirurgia , Assimetria Facial/cirurgia , Maxila/cirurgia , Osteogênese por Distração/métodos , Ritidoplastia/métodos , Feminino , Humanos , Masculino
7.
Pulm Pharmacol Ther ; 32: 37-44, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25861737

RESUMO

The prostaglandin D2 (PGD2) receptor, CRTH2, plays a role in allergic airway inflammation. The efficacy of BI 671800, a CRTH2 antagonist, was assessed in 2 separate trials in patients with asthma, in either the absence or the presence of inhaled corticosteroid (ICS) therapy. In this study, BI 671800 (50, 200 or 400 mg) and fluticasone propionate (220 µg) all given twice daily (bid) were compared with bid placebo in symptomatic controller-naïve adults with asthma (Trial 1), and BI 671800 400 mg bid compared with montelukast 10 mg once daily (qd), and matching placebo bid, in patients with asthma receiving inhaled fluticasone (88 µg bid) (Trial 2). The primary endpoint in both trials was change from baseline in trough forced expiratory volume in 1 s (FEV1) percent predicted. After 6 weeks' treatment, adjusted mean treatment differences (SE) for the primary endpoint compared with placebo in Trial 1 were 3.08% (1.65%), 3.59% (1.60%) and 3.98% (1.64%) for BI 671800 50, 200 and 400 mg bid, respectively, and 8.62% (1.68%) for fluticasone 220 µg bid (p = 0.0311, p = 0.0126, p = 0.0078 and p < 0.0001, respectively). In Trial 2, adjusted mean FEV1 (SE) treatment differences compared with placebo were 3.87% (1.49%) for BI 671800 400 mg bid and 2.37% (1.57%) for montelukast (p = 0.0050 and p = 0.0657, respectively). These findings suggest that BI 671800 is associated with a small improvement in FEV1 in symptomatic controller-naïve asthma patients, and in patients on ICS.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Benzamidas/uso terapêutico , Pirimidinas/uso terapêutico , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Administração por Inalação , Adulto , Antiasmáticos/administração & dosagem , Antiasmáticos/farmacologia , Asma/fisiopatologia , Benzamidas/administração & dosagem , Benzamidas/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fluticasona/administração & dosagem , Fluticasona/uso terapêutico , Volume Expiratório Forçado , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia , Resultado do Tratamento , Adulto Jovem
8.
Int J Gynecol Cancer ; 24(6): 967-72, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24978707

RESUMO

Diagnosis of ovarian mass during pregnancy is a rare event. Treatment of ovarian malignancies during pregnancy depends on histology, grade, stage, and gestational weeks. When possible, surgical excision is indicated, and sometimes, fertility-sparing surgery is recommended. Administration of systemic treatment before or after surgery is indicated as in nonpregnant women. Preliminary data suggest that platinum salts and taxanes are safe during pregnancy. Management of ovarian tumors in pregnancy requires a multidisciplinary approach to guarantee an optimal treatment for the mother and the fetus.


Assuntos
Infertilidade Feminina/prevenção & controle , Neoplasias Ovarianas/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Infertilidade Feminina/etiologia , Gravidez
9.
J Nanosci Nanotechnol ; 14(7): 4960-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24757967

RESUMO

Few layer graphene oxide (GO) nanosheets were prepared by a very fast modified Hummers method and widely characterized. Avoiding further chemical reactions, trying to take advantage of the easy exfoliation of GO favoring the formation of a tribofilm, and using a methodology well known to the lubricant industry, they were added to a mineral oil by the help of a dispersant. The tribological behaviour of GO in mineral oil was investigated under a wide spectrum of conditions, from boundary and mixed lubrication to elastohydrodynamic regimes. A ball on disc setup tribometer has been used to verify the friction reduction due to nanosheets dispersed in mineral oil. Their good friction and anti-wear properties may possibly be attributed to the small and extremely thin laminated structure, which offer lower shear stress and prevent interaction between metal interfaces. Furthermore, the results clearly prove that graphene platelets in oil easily form a protective film to prevent the direct contact between steel surfaces and, thereby, improving the frictional behaviour of the base oil. This evidence is also related to the frictional coefficient trend in boundary regime.

10.
Sci Rep ; 14(1): 2163, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272966

RESUMO

In the present paper, multifunctional flower-like nanoparticles were synthesized to be used in the leather finishing. They are capable of conferring simultaneously and synergistic antimicrobial, self-cleaning, light resistance, hydrophobic, mechanical, thermal, and fluorescent properties due to the presence of Ag, TiO2, and SiO2 NPs. These nanoparticles form a "flower-like" structure in which the "pistil" is made up of TiO2 and the "petals" that surround it of silver nanoparticles and silica nanoparticles, whose dimensions are of the order of ten nanometers. Their surfaces enjoy abundant hydrophilic functionalities to be dispersed within inks commonly used during the leather finishing process. Leathers functionalized with these nanomaterials showed significantly improved self-cleaning properties after 15 h of exposure to UV light, and antibacterial properties 10 times higher than that shown by the untreated samples. Aging tests were performed (ISO 105-B02, ISO 17228, SAEJ 2412). ΔE, color variation decreased by approximately 30%, if compared with samples not refined with flower-like NPs. Furthermore, the results of the mechanical tests (ISO 17076, FCA 50444) evidence amazing properties, e.g. abrasion resistance more than significantly improved, increase in resistance from 1500 cycles for the untreated samples to 3000 cycles for the leathers finished with flower-like NPs. The contact angle analysis, capturing the angle that traces the air-water to water-substrate interface from the origin of the air-water-substrate contact point at the edge, is practically unchanged after 10 s in the case of nanoparticles containing finishing.

11.
Sci Rep ; 14(1): 14998, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951136

RESUMO

Herein, additive manufacturing, which is extremely promising in different sectors, has been adopted in the electrical energy storage field to fabricate efficient materials for supercapacitor applications. In particular, Al2O3-, steel-, and Cu-based microparticles have been used for the realization of 3D self-assembling materials covered with reduced graphene oxide to be processed through additive manufacturing. Functionalization of the particles with amino groups and a subsequent "self-assembly" step with graphene oxide, which was contextually partially reduced to rGO, was carried out. To further improve the electrical conductivity and AM processability, the composites were coated with a polyaniline-dodecylbenzene sulfonic acid complex and further blended with PLA. Afterward, they were extruded in the form of filaments, printed through the fused deposition modeling technique, and assembled into symmetrical solid-state devices. Electrochemical tests showed a maximum mass capacitance of 163 F/g, a maximum energy density of 15 Wh/Kg at 10 A/g, as well as good durability (85% capacitance retention within 5000 cycles) proving the effectiveness of the preparation and the efficiency of the as-manufactured composites.

12.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38543140

RESUMO

Pheochromocytomas (PCCs) and Paragangliomas (PGLs), commonly known as PPGLs to include both entities, are rare neuroendocrine tumors that may arise in the context of hereditary syndromes or be sporadic. However, even among sporadic PPGLs, identifiable somatic alterations in at least one of the known susceptibility genes can be detected. Therefore, about 3/4 of all PPGL patients can be assigned to one of the three molecular clusters that have been identified in the last years with difference in the underlying pathogenetic mechanisms, biochemical phenotype, metastatic potential, and prognosis. While surgery represents the mainstay of treatment for localized PPGLs, several therapeutic options are available in advanced and/or metastatic setting. However, only few of them hinge upon prospective data and a cluster-oriented approach has not yet been established. In order to render management even more personalized and improve the prognosis of this molecularly complex disease, it is undoubtable that genetic testing for germline mutations as well as genome profiling for somatic mutations, where available, must be improved and become standard practice. This review summarizes the current evidence regarding diagnosis and treatment of PPGLs, supporting the need of a more cluster-specific approach in clinical practice.

13.
Nanotechnology ; 24(7): 075704, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23358596

RESUMO

Measurements of the absorbed dose and quality assurance programs play an important role in radiotherapy. Ionization chambers (CIs) are considered the most important dosimeters for their high accuracy, practicality and reliability, allowing absolute dose measurements. However, they have a relative large physical size, which limits their spatial resolution, and require a high bias voltage to achieve an acceptable collection of charges, excluding their use for in vivo dosimetry. In this paper, we propose new real time radiation detectors with electrodes based on graphene or vertically aligned multiwall carbon nanotubes (MWCNTs). We have investigated their charge collection efficiency and compared their performance with electrodes made of a conventional material. Moreover, in order to highlight the effect of nanocarbons, reference radiation detectors were also tested. The proposed dosimeters display an excellent linear response to dose and collect more charge than reference ones at a standard bias voltage, permitting the construction of miniaturized CIs. Moreover, an MWCNT based CI gives the best charge collection efficiency and it enables working also to lower bias voltages and zero volts, allowing in vivo applications. Graphene based CIs show better performance with respect to reference dosimeters at a standard bias voltage. However, at decreasing bias voltage the charge collection efficiency becomes worse if compared to a reference detector, likely due to graphene's semiconducting behavior.


Assuntos
Grafite/química , Nanotubos de Carbono/química , Radiometria/instrumentação , Cobre/química , Relação Dose-Resposta à Radiação , Eletricidade , Eletrodos , Nanotubos de Carbono/ultraestrutura , Silício/química
14.
Nanotechnology ; 24(12): 125601, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23459162

RESUMO

Hybrid organic-inorganic oleylamine@MoS2-CNT nanocomposites with different compositions were obtained by thermal decomposition of tetrathiomolybdate in the presence of oleylamine and high quality multiwalled carbon nanotubes (CNTs) previously prepared by the CCVD technique. The nanocomposite samples were characterized by the TEM, SEM TG-MS, Raman and XRD techniques and successfully tested as anti-friction and anti-wear additives for grease lubricants.

15.
Materials (Basel) ; 16(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37374430

RESUMO

The AC magnetic properties of a sample of Fe3O4 nanoparticles coated with oleic acid have been investigated with the help of AC susceptibility measurements. In particular, several DC magnetic fields have been superimposed on the AC field, and their effect on the magnetic response of the sample has been analysed. The results show the presence of a double peak structure in the imaginary component of the complex AC susceptibility measured as a function of the temperature. A preliminary evaluation of the Mydosh parameter for both peaks gives the information that each one of them is associated with a different state of interaction between nanoparticles. The two peaks evolve both in amplitude and position when the intensity of the DC field is changed. The field dependence of the peak position shows two different trends, and it is possible to study them in the framework of the currently existing theoretical models. In particular, a model of non-interacting magnetic nanoparticles has been used to describe the behaviour of the peak at lower temperatures, whereas the behaviour of the peak at higher temperatures has been analysed in the framework of a spin-glass-like model. The proposed analysis technique can be useful for the characterisation of magnetic nanoparticles used in several types of applications, such as biomedical and magnetic fluids.

16.
Materials (Basel) ; 16(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570012

RESUMO

Nowadays, iron (II) selenide (FeSe), which has been widely studied for years to unveil the high-temperature superconductivity in iron-based superconductors, is drawing increasing attention in the electrical energy storage (EES) field as a supercapacitor electrode because of its many advantages. In this study, very small FeSe particles were synthesized via a simple, low-cost, easily scalable, and reproducible solvothermal method. The FeSe particles were characterized using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) measurements, and electrochemical impedance spectroscopy (EIS), revealing enhanced electrochemical properties: a high capacitance of 280 F/g at 0.5 A/g, a rather high energy density of 39 Wh/kg and a corresponding power density of 306 W/kg at 0.5 A/g, an extremely high cycling stability (capacitance retention of 92% after 30,000 cycles at 1 A/g), and a rather low equivalent series resistance (RESR) of ~2 Ω.

17.
Materials (Basel) ; 16(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38005111

RESUMO

Supercapacitors have attracted considerable attention due to their advantages, including being lightweight and having rapid charge-discharge, a good rate capability, and high cyclic stability. Electrodes are one of the most important factors influencing the performance of supercapacitors. Herein, a three-dimensional network of rough and porous micropebbles of CeCu2Si2 has been prepared using a one-step procedure and tested for the first time as a supercapacitor electrode. The synthesized material was extensively characterized in a three-electrode configuration using different electrochemical techniques, such as cyclic voltammetry (CV), galvanostatic charge and discharge (GCD) tests, and electrochemical impedance spectroscopy (EIS). CeCu2Si2 shows rather high mass-capacitance values: 278 F/g at 1 A/g and 295 F/g at 10 mV/s. Moreover, the material exhibits remarkable long-term stability: 98% of the initial capacitance was retained after 20,000 cycles at 10 A/g and the Coulombic efficiency remains equal to 100% at the end of the cycles.

18.
Materials (Basel) ; 16(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37297195

RESUMO

Polyvinyl alcohol is the most commercially water-soluble biodegradable polymer, and it is in use for a wide range of applications. It shows good compatibility with most inorganic/organic fillers, and enhanced composites may be prepared without the need to introduce coupling agents and interfacial modifiers. The patented high amorphous polyvinyl alcohol (HAVOH), commercialized with the trade name G-Polymer, can be easily dispersed in water and melt processed. HAVOH is particularly suitable for extrusion and can be used as a matrix to disperse nanocomposites with different properties. In this work, the optimization of the synthesis and characterization of HAVOH/reduced graphene oxide (rGO) nanocomposite obtained by the solution blending process of HAVOH and Graphene Oxide (GO) water solutions and 'in situ' reduction of GO is studied. The produced nanocomposite presents a low percolation threshold (~1.7 wt%) and high electrical conductivity (up to 11 S/m) due to the uniform dispersion in the polymer matrix as a result of the solution blending process and the good reduction level of GO. In consideration of HAVOH processability, the conductivity obtained by using rGO as filler, and the low percolation threshold, the nanocomposite presented here is a good candidate for the 3D printing of a conductive structure.

19.
J Nanosci Nanotechnol ; 11(11): 10053-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413344

RESUMO

The synthesis of polynorbornene by ring opening metathesis polymerization (ROMP), in the presence of 1st and 2nd generation Grubbs catalyst-functionalized multiwalled carbon nanotubes (MWCNT), has been studied. MWCNTs were obtained by catalytic chemical vapour deposition (CCVD) of ethylene. A full characterization of the 1st and 2nd generation Grubbs catalyst-functionalized nanotubes was performed by FTIR and TG-DTG-MS. The amount of catalyst grafted to the nanotube surface was estimated. The activity of the catalyst-functionalized nanotubes in ROMP of 2-norbornene was found to be similar to that of bare 1st and 2nd generation Grubbs catalysts. The characterization of polynorbornene-carbon nanotube composites shows that the nanotubes are well dispersed in the polymer matrix.

20.
Nanomaterials (Basel) ; 11(6)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072358

RESUMO

A supercritical CO2 drying process was used to prepare an innovative nanocomposite, formed by a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF HFP) aerogel loaded with RuO2 nanoparticles. The produced nanocomposites, at 10% and 60% w/w of RuO2, were tested for the electrochemical oxidation of model tannery wastewaters. The effect of the electrochemical oxidation parameters, like pH, temperature, and current density, on tannic acid, intermediates, and chemical oxygen demand (COD) removal, was investigated. In particular, the electrolysis of a simulated real tannery wastewater, using PVDF HFP_RuO2 60, was optimized working at pH 10, 40 °C, and setting the current density at 600 A/m2. Operating in this way, surfactants, sulfides, and tannins oxidation was achieved in about 2.5 h, ammonium nitrogen oxidation in 3 h, and COD removal in 5 h. When chloride-containing solutions were tested, the purification was due to indirect electrolysis, related to surface redox reactions generating active chlorine. Moreover, sulfide ions were converted into sulfates and ammonium nitrogen in gaseous N2.

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