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1.
Clin Ther ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38763818

RESUMO

PURPOSE: The case of a 47-year-old female patient who underwent sigmoidectomy for metastatic colorectal cancer is reported. Treatment with capecitabine and 5-fluorouracil induced severe hypertriglyceridemia repeatedly. METHODS: Based on laboratory tests and clinical evaluations, treatment was suggested by specialists. FINDINGS: After treatment with capecitabine, the patient's triglycerides increased from 19.7 mmol/L to 42 mmol/L. It was proposed that the patient had multifactorial chylomicronemia syndrome triggered by secondary factors. Statins, fenofibrate, ezetimib, and metformin were added to the therapy. After metastases appeared, FOLFIRI (leucovorin calcium [folinic acid], 5-fluorouracil, and irinotecan hydrochloride) chemotherapy and biological treatment (cetuximab) followed and triglycerides increased to 55.3 mmol/L. IMPLICATIONS: Monitoring triglyceride levels before and during therapy is suggested.

2.
RSC Adv ; 14(22): 15220-15231, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38737968

RESUMO

The microstructure and physical properties of reflective and black aluminum were compared for layers of different thicknesses deposited by magnetron sputtering on fused silica substrates. Reflective Al layers followed the Volmer-Weber growth mechanism classically observed for polycrystalline metal films. On the contrary, the extra nitrogen gas used to deposit the black aluminum layers modified the growth mechanism and changed the film morphologies. Nitrogen cumulated in the grain boundaries, favoring the pinning effect and stopping crystallite growth. High defect concentration, especially vacancies, led to strong columnar growth. Properties reported for black aluminum tend to be promising for sensors and emissivity applications.

3.
Front Psychol ; 15: 1280071, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455118

RESUMO

Introduction: Increasing overweight and obesity rates represent one of the global public health challenges. COM-B is a theoretical model used to identify areas to target to achieve behavior change. It identifies three factors that are needed for any behavior to occur: capability, opportunity, and motivation. We aimed to assess the potential facilitators and barriers to behavior change in weight management using the COM-B. Methods: The study included 139 people with overweight and obesity (mean age 48.81 ± 14.49 years; 64.5% female; body mass index 32.64 ± 6.51 kg/m2; waist-to-height ratio 0.62 ± 0.10) from primary care settings. All participants completed the Brief Measure of Behavior Change (COM-B), the General Self-Efficacy Scale (GSE), the Rosenberg Self-esteem Scale (RSE), and the Overall Evaluation of Health (OEH). Multiple linear regression was performed to analyse the data. Results: The associations between sociodemographic and clinical variables and COM-B domains attenuated or were no longer significant when psychological resources were added to the regression models. Self-efficacy was identified as a stronger facilitator of health behavior change (p < 0.001) when compared to self-esteem (p < 0.05). No associations between automatic motivation and psychological resources were identified, however. Automatic motivation was found to be associated with higher age, being in a relationship, and better health. Discussion: Behavioral interventions for weight management should specifically target different components of COM-B. Self-efficacy and self-esteem may play a significant role in individual capabilities, opportunities, and reflective motivation and should be included in tailored public health interventions. Health programs targeting younger and single people, and people with chronic conditions may help to promote sustainable behavior change.

4.
Materials (Basel) ; 16(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570092

RESUMO

The phase structure and composition of a series of four alloys based on Fe3Al was investigated by means of scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The materials were composed of Fe and Al with a fixed ratio of 3:1 alloyed with V, Cr and Ni at 8, 12, 15 and 20 at. % each (composition formula: Fe3(100-3x)/4 Al(100-3x)/4VxCrxNix). For 8% alloying, the material is single-phase D03. Furthermore, 12 and 15% alloying results in bcc-B2 phase separation on two length scales. Moreover, 20% alloying gives rise to the FeNiCrV σ phase supplemented by B2. These findings are discussed with respect to the results obtained via Calphad modeling using the TCHEA5 database and can serve in further improvement.

5.
Materials (Basel) ; 16(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36770305

RESUMO

Two novel ignition-resistant magnesium alloys, Mg-2Gd-2Y-1Ca and Mg-2Nd-1Y-1Ca, were prepared in the ultrafine-grain condition by equal channel angular pressing (ECAP). In addition, four commercial alloys-AZ31, AX41, AE42 and WE43-were prepared similarly as a reference. The microstructure, mechanical properties and ignition temperature were thoroughly investigated. Both novel alloys exhibited a mean grain size of ~1 µm and dense distribution of small secondary phase particles. The mechanical strength measured by the tensile deformation test showed that the novel alloys are much stronger (~290 MPa) than all commercial alloys except WE43. However, Ca segregation into the grain boundaries caused a significant decrease in ductility (<6%). The ignition temperature of the novel alloys (~950 °C) was considerably improved by the presence of Gd/Nd, Y and Ca. This study showed that both novel alloys exhibit high strength and high ignition temperature in the ultrafine-grain condition.

6.
Materials (Basel) ; 15(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36363132

RESUMO

The magnesium AZ31 alloy was swaged with rotary pressure with the aim of redefining the microstructure and improving mechanical and fatigue properties. The rotary swaging process and subsequent ageing improved the yield stress in tension and compression. In the present study, the investigation was focused on fatigue behaviour. The samples were cycled in a symmetric regime with a frequency of 35 Hz. A dependence of the stress amplitude on the number of cycles up to the fracture was estimated. The microstructure of the samples and fracture surfaces was analysed with a scanning electron microscope. The fatigue process was influenced by the pronounced texture formed in the swaging process. The fatigue properties of the swaged samples improved substantially-the endurance limit based on 107 cycles was approximately 120 MPa-compared to those of the cast alloy. The analysis of the fracture surfaces showed a transcrystalline fatigue fracture.

7.
Materials (Basel) ; 15(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36363162

RESUMO

In the field of magnesium-based degradable implantable devices, the Mg-Y-RE-Zr alloying system (WE-type) has gained popularity due to its satisfying degradation rate together with mechanical strength. However, utilization of RE and Zr in the WE-type alloys was originally driven to improve Mg-based alloys for high-temperature applications in the industry, while for medical purposes, there is a question of whether the amount of alloying elements may be further optimized. For this reason, our paper presents the Mg-3Y (W3) magnesium alloy as an alternative to the WE43 alloy. This study shows that the omission of RE and Zr elements did not compromise the corrosion resistance and the degradation rate of the W3 alloy when compared with the WE43 alloy; appropriate biocompatibility was preserved as well. It was shown that the decrease in the mechanical strength caused by the omission of RE and Zr from the WE43 alloy could be compensated for by severe plastic deformation, as achieved in this study, by equal channel angular pressing. Ultrafine-grained W3 alloy exhibited compression yield strength of 362 ± 6 MPa and plastic deformation at maximum stress of 18 ± 1%. Overall, the early results of this study put forward the motion of avoiding RE elements and Zr in magnesium alloy as a suitable material for biodegradable applications and showed that solo alloying of yttrium is sufficient for maintaining desirable properties of the material at once.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35682464

RESUMO

Colorectal cancer is one of the most common cancers in Europe and the world. Cancer treatments have side effects and cause significant deterioration of the patient's nutritional status. Patient malnutrition may worsen the health condition and prevent the deliberate effects of the therapy. The aim of this review was to describe the available data about clinical nutrition in colorectal cancer patients. A large proportion of colorectal cancer patients suffer from malnutrition, which negatively affects the survival prognosis, quality of life, and oncological therapy. Therefore, monitoring nutritional status during the treatment is essential and can be used to arrange proper nutritional therapy to enhance patient responses, prevent side effects, and shorten recovery time. The principles of nutrition during anticancer therapy should mainly consider light and low-fat foods, the exclusion of lactose and gluten-containing foods in certain cases, or the introduction of special dietary products such as oral nutrition supplements and it should be tailored to patients' individual needs.


Assuntos
Neoplasias Colorretais , Desnutrição , Terapia Nutricional , Neoplasias Colorretais/terapia , Humanos , Desnutrição/etiologia , Estado Nutricional , Qualidade de Vida
9.
Materials (Basel) ; 15(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35268946

RESUMO

This paper investigates surface state after turning of the high tempered bearing steel 100Cr6 with a hardness of 40 HRC. White layer (WL) thickness and its microhardness, as well as surface roughness, are investigated as a function of tool flank wear VB as well as cutting speed vc. The mechanical and thermal load of the machined surface were analysed in order to provide a deeper insight into their superimposing contribution. Cutting energy expressed in terms of cutting force was analyses as that consumed for chip formation Fγ and consumed in the flank wear land Fα. It was found that the mechanical energy expressed in terms of the shear components of the Fα grows with VB, converts to the heat and strongly affects the thickness of the re-hardened layer. Furthermore, the superimposing contribution of the heat generation and its duration in the VB region should also be taken into account. It was also found that the influence of VB predominates over the variable cutting speed.

10.
Materials (Basel) ; 15(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35269130

RESUMO

This study deals with monitoring of Zn layer heterogeneity on the flange of steel road barriers using magnetic measurements. The Barkhausen noise technique is employed for such purpose, and parameters extracted from Barkhausen noise signals are correlated with the true thickness of the Zn layer. The true values of the Zn layer were obtained from the metallographic images, as well as the thickness gauge CM-8825FN (Guangzhou Landtek Instruments Co. Ltd., Guangzhou, China) device. It was observed that the diffusion region lies below the Zn protective layer, which makes the thickness of the Zn layer obtained from the CM-8825FN device thicker than that measured on the metallographic images. For this reason, the chemical gradient of Zn below the Zn layer can be reported, and it affects Barkhausen noise emission. Barkhausen noise decreases along with increasing thickness of the Zn layer, and Barkhausen noise envelopes are shifted to stronger magnetic fields. The number of strong MBN pulses drops down with the increasing thickness of Zn coating at the expense of the increasing number of the weak MBN pulses. The thickness of Zn coating can be polluted by the solidification of Zn melt after galvanizing. The presence of the diffusion layer dims the contrast between ferromagnetic and paramagnetic phases.

11.
Sci Rep ; 12(1): 973, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046424

RESUMO

Organic dyes such as methyl orange (MO) and methylene blue (MB) are widely used in different industries and have become one of the leading emerging water contaminants. The purpose of the current research is to develop new polymer nanocomposite filters for the effective elimination of the dyes, which are non-biodegradable and not efficiently removed by traditional treatment methods. New padded and covered filters were produced applying polystyrene-acrylic/ZnO nanocomposite on the polyester surface by blade coating and one-bath pad methods. Principal results determined by SEM analysis confirm that functionalised layer can create unprecedented function of filter textile material depending on the way of treatment. Due to the modification, the surface area increased from 5.9 for untreated polyester to 85.2 (padded), 44.6 (covered) m2/g. The measured pore size of produced filters is around 3.4 nm, which corresponds to the mesoporous structure. Our study reported effective filters with the rate of MB and MO removal efficiencies up to 60%. Moreover, a colourless reduced form of MB-leuco-methylene blue (LMB) could be created. The functionalised layer of the developed filters through hydrogen bonding between the -OH groups of styrene-acrylic molecules and the -N(CH3)2 groups on LMB can stabilise LMB.

12.
Materials (Basel) ; 14(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34947364

RESUMO

Aluminium steel clad materials have high potential for industrial applications. Their mechanical properties are governed by an intermetallic layer, which forms upon heat treatment at the Al-Fe interface. Transmission electron microscopy was employed to identify the phases present at the interface by selective area electron diffraction and energy dispersive spectroscopy. Three phases were identified: orthorhombic Al5Fe2, monoclinic Al13Fe4 and cubic Al19Fe4MnSi2. An effective interdiffusion coefficient dependent on concentration was determined according to the Boltzmann-Matano method. The highest value of the interdiffusion coefficient was reached at the composition of the intermetallic phases. Afterwards, the process of diffusion considering the evaluated interdiffusion coefficient was simulated using the finite element method. Results of the simulations revealed that growth of the intermetallic phases proceeds preferentially in the direction of aluminium.

13.
Materials (Basel) ; 13(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348844

RESUMO

Pure polycrystalline cobalt is systematically thermally treated in order to assess the effect of the microstructure on the compression behavior. Isothermal annealing of the as-drawn material leads to recrystallization and grain growth dependent on the annealing temperature (600-1100 ∘C). Consequently, the yield strength decreases and the fracture strain increases as a function of rising grain size; the content of the residual fcc phase is ~6-11%. Subsequent thermal cycling around the transition temperature is applied to further modify the microstructure, especially in terms of the fcc phase content. With the increasing number of cycles, the grain size further increases and the fraction of the fcc phase significantly drops. At the same time, the values of both the yield strength and fracture strain somewhat decrease. An atypical decrease in the fracture strain as a function of grain size is explained in terms of decreasing fcc phase content; the stress-induced fcc→hcp transformation can accommodate a significant amount of plastic strain. Besides controlling basic material parameters (e.g., grain size and texture), adjusting the content of the fcc phase can thus provide an effective means of mechanical performance optimization with respect to particular applications.

14.
Materials (Basel) ; 13(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911734

RESUMO

The spark plasma sintering (SPS) technique was employed to prepare compacts from (i) gas-atomized and (ii) attritor-milled AE42 magnesium powder. Short attritor-milling was used mainly to disrupt the MgO shell covering the powder particles and, in turn, to enhance consolidation during sintering. Compacts prepared by SPS from the milled powder featured finer microstructures than compacts consolidated from gas-atomized powder (i.e., without milling), regardless of the sintering temperatures in the range of 400-550 °C. Furthermore, the grain growth associated with the increase in the sintering temperature in these samples was less pronounced than in the samples prepared from gas-atomized particles. Consequently, the mechanical properties were significantly enhanced in the material made of milled powder. Apart from grain refinement, the improvements in mechanical performance were attributed to the synergic effect of the irregular shape of the milled particles and better consolidation due to effectively disrupted MgO shells, thus suppressing the crack formation and propagation during loading. These results suggest that relatively short milling of magnesium alloy powder can be effectively used to achieve superior mechanical properties during consolidation by SPS even at relatively low temperatures.

15.
Materials (Basel) ; 13(3)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050531

RESUMO

Magnesium samples reinforced with 0.7, 1.4, and 2.4 vol.% of Inconel 718 particles were prepared using a disintegrated melt deposition technique followed by hot extrusion. Mechanical properties, thermal expansion, and damping were studied with the aim of revealing the particle influence on the microstructure, texture, tensile and compressive behavior, thermal expansion coefficient, and internal friction. The flow stresses are significantly influenced by the test temperature and the vol.% of particles. A substantial asymmetry in the tensile and compressive properties was observed at lower temperatures. This asymmetry is caused by different deformation mechanisms operating in tension and compression. The fiber texture of extruded composite samples, refined grain sizes, and the increased dislocation density improved the mechanical properties. On the other hand, a decrease in the thermal expansion coefficient and internal friction was observed.

16.
Materials (Basel) ; 14(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396375

RESUMO

An extruded magnesium AZ31 magnesium alloy was processed by rotary swaging (RSW) and then deformed by tension and compression at room temperature. The work-hardening behaviour of 1-5 times swaged samples was analysed using Kocks-Mecking plots. Accumulation of dislocations on dislocation obstacles and twin boundaries is the deciding factor for the strain hardening. Profuse twinning in compression seems to be the reason for the higher hardening observed during compression. The main softening mechanism is apparently the cross-slip between the pyramidal planes of the second and first order. A massive twinning observed at the deformation beginning influences the Hall-Petch parameters.

17.
J Mech Behav Biomed Mater ; 98: 213-224, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31271978

RESUMO

This study investigates the morphology, microstructure, compressive behavior, biocorrosion properties, and cytocompatibility of magnesium (Mg)-aluminum (Al) alloy (AE42) scaffolds for their potential use in biodegradable biomedical applications. Mg alloy scaffolds were successfully synthesized via a camphene-based freeze-casting process with precisely controlled heat treatment. The average porosity was approximately 52% and the median pore diameter was ∼13 µm. Salient deformation mechanisms were identified using acoustic emission (AE) signals and adaptive sequential k-means (ASK) analysis. Twinning, dislocation slip, strut bending, and collapse were dominant during compressive deformation. Nonetheless, the overall compressive behavior and deformation mechanisms were similar to those of bulk Mg based on ASK analysis. The corrosion potential of the Mg alloy scaffold (-1.44 V) was slightly higher than that of bulk AE42 (-1.60 V), but the corrosion rate of the Mg alloy scaffold was faster than that of bulk AE42 due to the enhanced surface area of the Mg alloy scaffold. As a result of cytocompatibility evaluation following ISO10993-5, the concentration of the Mg alloy scaffold extract reducing cell growth rate to 50% (IC50) was 10.7%, which is higher (less toxic) than 5%, suggesting no severe inflammation by implantation into muscle.


Assuntos
Ligas/química , Alumínio/química , Materiais Biocompatíveis/química , Magnésio/química , Fenômenos Mecânicos , Corrosão , Eletroquímica , Teste de Materiais
18.
Nanomaterials (Basel) ; 9(8)2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349688

RESUMO

Layered-graphene reinforced-metal matrix nanocomposites with excellent mechanical properties and low density are a new class of advanced materials for a broad range of applications. A facile three-step approach based on ultra-sonication for dispersion of graphene nanosheets (GNSs), ball milling for Al-powder mixing with different weight percentages of GNSs, and equal-channel angular pressing for powders' consolidation at 200 °C was applied for nanocomposite fabrication. The Raman analysis revealed that the GNSs in the sample with 0.25 wt.% GNSs were exfoliated by the creation of some defects and disordering. X-ray diffraction and microstructural analysis confirmed that the interaction of the GNSs and the matrix was almost mechanical, interfacial bonding. The density test demonstrated that all samples except the 1 wt.% GNSs were fully densified due to the formation of microvoids, which were observed in the scanning electron microscope analysis. Investigation of the mechanical properties showed that by using Al powders with commercial purity, the 0.25 wt.% GNS sample possessed the maximum hardness, ultimate shear strength, and uniform normal displacement in comparison with the other samples. The highest mechanical properties were observed in the 0.25 wt.% GNSs composite, resulting from the embedding of exfoliated GNSs between Al powders, excellent mechanical bonding, and grain refinement. In contrast, agglomerated GNSs and the existence of microvoids caused deterioration of the mechanical properties in the 1 wt.% GNSs sample.

19.
Saudi Pharm J ; 27(4): 574-583, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31061627

RESUMO

BACKGROUND: Up to now, there have been no data on patient counselling in the Slovak community pharmacies. The literature provides a wide range of activities for which mystery shopping methodology be used, including assessment of patient counselling. AIMS AND OBJECTIVES: To assess patient counselling on the common cold treatment with OTC medicine containing zinc provided by Slovak community pharmacists. To analyse this counselling considering the set scenarios, counsellors and their age. METHODS: 54 pharmacy students visited 270 different community pharmacies throughout Slovakia in 2 weeks in October 2016 to conduct mystery shopping with set scenarios. For assessment of patient counselling, we defined Counselling Performance. It was conceptualised as weighted mean percentage counselling successes rate of its three categories (Identification, Information and Communication) and their weights. Individual perception of counselling evaluated separately. Student t-test and Person's chi-squared test (p < 0.05) and Cohen delta were used for comparing outcomes and effect size of counselling. A simple linear regression was used to find relationships. RESULTS: The total Counselling Performance was 39.0 ±â€¯22.4%, Identification 30.6 ±â€¯28.7%, Information 39.8 ±â€¯25.1% and Communication 74.3 ±â€¯11.5%. 26.3% pharmacies achieved the average Counselling Performance (41-60%). Subjective Perception had a success rate of 73.4 ±â€¯21.2%, but it could be predicted by the Counselling Performance and the success rate of the three categories only in 1/5 pharmacies. Spontaneous counselling was provided more by pharmacy technicians (p = 0.0009). The duration of counselling was similar when comparing both scenarios, counsellors and their age. The product-requested scenario achieved a higher success rate in the Information category (p = 0.0304; d = 0.27). Pharmacists achieved a higher Counselling Performance (p < 0.0001; d = 0.48) and success rate in categories Identification (p = 0.0001, d = 0.46), Information (p = 0.0004, d = 0.37), and Perception (p = 0.0007; d = 0.54). The estimated age of counsellors did not have any impact on the counselling. CONCLUSION: Patient counselling on the common cold showed a suboptimal level, particularly considering its content. In the study, we found a significant relationship between the success of counselling and counsellors.

20.
Mater Sci Eng C Mater Biol Appl ; 97: 367-376, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678922

RESUMO

We synthesized Fe foams using water suspensions of micrometric Fe2O3 powder by reducing and sintering the sublimated Fe oxide green body to Fe under 5% H2/Ar gas. The resultant Fe foam showed aligned lamellar macropores replicating the ice dendrites. The compressive behavior and deformation mechanism of the synthesized Fe foam were studied using an acoustic emission (AE) method, with which we detected sudden localized structural changes in the Fe foam material. The evolution of the deformation mechanism was elucidated using the adaptive sequential k-means (ASK) algorithm; specifically, the plastic deformation of the cell struts was followed by localized cell collapse, which eventually led to fracturing of the cell walls. For potential biomedical applications, the corrosion and biocompatibility characteristics of the two synthesized Fe foams with different porosities (50% vs. 44%) were examined and compared. Despite its larger porosity, the superior corrosion behavior of the Fe foam with 50% porosity can be attributed to its larger pore size and smaller microscopic surface area. Based on the cytotoxicity tests for the extracts of the foams, the Fe foam with 44% porosity showed better cytocompatibility than that with 50% porosity.


Assuntos
Acústica , Materiais Biocompatíveis/química , Ferro/química , Substâncias Viscoelásticas/química , Animais , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Força Compressiva , Corrosão , Eletroquímica/métodos , Compostos Férricos/química , Fibroblastos , Ferro/toxicidade , Teste de Materiais , Camundongos , Porosidade , Difração de Raios X
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