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1.
Molecules ; 28(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38138625

RESUMO

Recovered carbon blacks (rCBs) produced from end-of-life tires using pyrolysis were transformed into solid acid catalysts for the synthesis of acetins, i.e., products with a wide spectrum of practical applications. Tuning the chemical properties of the surface of samples and introducing specific functional groups on the rCBs were achieved through carbon functionalization with concentrated H2SO4. The initial and modified rCBs were thoroughly characterized using techniques such as elemental analysis, potentiometric back titration, thermogravimetric technique, scanning and transmission microscopy, X-ray photoelectron spectroscopy, etc. The catalytic activities of the samples were measured via batch mode glycerol acetylation performed at 110 °C and compared to the catalytic performance of the functionalized commercial carbon black. The modified rCBs were found to show a significant catalytic effect in the tested reaction, giving high glycerol conversions (above 95%) and satisfactory combined yields of diacetins and triacetin (~72%) within 4 h; this behavior was attributed to the presence of -SO3H moieties on the surface of functionalized rCBs. The reusability tests indicated that the modified samples were catalytically stable in subsequent acetylation runs. The obtained results evidenced the feasibility of using end-of-life tires for the production of effective acid catalysts for glycerol valorization processes.

2.
Molecules ; 28(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37959732

RESUMO

The present work concerns proton-conducting composites obtained by replacing the water molecules present in aluminophosphate and silicoaluminophosphate AFI-type molecular sieves (AlPO-5 and SAPO-5) with azole molecules (imidazole or 1,2,4-triazole). Both the introduction of azoles and the generation of Brønsted acid centers by isomorphous substitution in aluminophosphate materials were aimed at improving the proton conductivity of the materials and its stability. In the presented study, AlPO-5 and several SAPO-5 materials differing in silicon content were synthesized. The obtained porous matrices were studied using PXRD, low-temperature nitrogen sorption, TPD-NH3, FTIR, and SEM. The proton conductivity of composites was measured using impedance spectroscopy. The results show that the increase in silicon content of the porous matrices is accompanied by an increase in their acidity. However, this does not translate into an increase in the conductivity of the azole composites. Triazole composites show lower conductivity and significantly higher activation energies than imidazole composites; however, most triazole composites show much higher stability. The different conductivity values for imidazole and triazole composites may be due to differences in chemical properties of the azoles.

3.
BMC Med Educ ; 23(1): 645, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679670

RESUMO

BACKGROUND: The recognition of the importance of effective communication in the healthcare system has been growing. Given that communication courses must be adjusted to the specificity of a particular culture, language, and other contextual issues, many countries and communities sharing a common language have proposed their recommendations for a communication curriculum for undergraduate medical education. To date, no recommendations have been developed for either any Central and Eastern Europe countries or for regions where Slavic languages are spoken. Their specificity of post-communist transformation should be acknowledged. This study aims to review communication curriculums and offer recommendations for medical communication training for undergraduate medical students in Poland. METHODS: The recommendations were developed through an iterative consultation process with lecturers, faculty members of medical schools, and education coordinators. PubMed and Google Scholar databases were searched to identify full text English and Polish language articles on communication curriculum for undergraduate medical education. Additionally, the new Regulation of the Polish Minister of Science and Higher Education, defining educational standards for undergraduate medical education was analysed in search of learning outcomes that could be applied in communication skills teaching. The authors extracted the most relevant communication skill competencies, as determined by the process participants, discussed current challenges, including those of the COVID-19 pandemic era, and indicated best practices. RESULTS: A review was conducted, and a set of recommendations was developed pertaining to the scope and methodology of teaching communication skills. The study included: (1) definition, (2) education content, (3) learning outcomes, (4) the recommended teaching methods. The recommendations are in concord with the graduate profile, as well as the current structure of medical studies. The authors listed and discussed the basic communication competencies expected of medical graduates, as well as medical communication course content viewed from different perspectives, including clinical, psychological, sociological, legal, and linguistic. CONCLUSIONS: Detailed recommendations aimed at integrating best practices into a comprehensive communication curriculum may promote successful teaching, learning, and assessment of medical communication.


Assuntos
COVID-19 , Educação de Graduação em Medicina , Humanos , Polônia , Pandemias , Currículo , Comunicação
4.
Z Evid Fortbild Qual Gesundhwes ; 171: 117-121, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35525719

RESUMO

The purpose of the present paper is to review the progress in recognition and implementation of shared decision-making (SDM) practice in the Polish health care system. In Poland, equal access to health care is a constitutional right. The foundations for SDM practice within the Polish health care system are laid in legislation regulating the professions of doctors and dentists, as well as patients' rights, which assert the duty of physicians to provide clear and patient-adjusted information on diagnostic and treatment options, health status and prognosis before obtaining consent. Over recent years, patient organizations have gained voice in the institutional setting. At the same time participatory decision-making at the individual patient level remains uneven, with a considerable variety between health care settings or even physicians. The challenges related to the implementation of SDM practices include low health care funding and staff shortages, which limit both the scope of available choices and consultation time. Fragmentation of care and inadequate standardization constitute additional barriers to the elaboration and sharing of good SDM practices.


Assuntos
Tomada de Decisões , Participação do Paciente , Alemanha , Política de Saúde , Humanos , Polônia
5.
Arch Med Sci ; 8(5): 854-8, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23185195

RESUMO

INTRODUCTION: Healthcare-associated infection is a common problem in patients from neonatal intensive care units and it is one of the leading causes of death in this group of patients. Healthcare-associated infections are associated with increases in mortality, morbidity, and prolonged length of hospital stay. The aim of the study was to assess the incidence, clinical presentation, mortality and aetiology of healthcare-associated infections in newborns in a neonatal intensive care unit between 2005 and 2010. MATERIAL AND METHODS: The research involved documentation of 2610 neonates hospitalized in this period in the Neonatal Intensive Care Unit, Dr Jan Biziel University Hospital No. 2 in Bydgoszcz. The incidence, clinical presentation, mortality and causative factors of healthcare-associated infections were assessed. RESULTS: The prevalence of healthcare-associated infections was 7.32%. The most frequent healthcare-associated infections were bloodstream infection (65.4%) and urinary tract infection (22.5%). The mortality rate was 2.1%. The most frequent pathogens were coagulase-negative staphylococci (36.1%) and Klebsiella pneumoniae (29.3%). CONCLUSIONS: The rate of healthcare-associated bloodstream infections in the analysed department is low, taking into consideration the specificity of the department. There is a necessity to establish convenient definitions of various kinds of healthcare-associated infecions in neonates, especially those born preterm.

6.
J Chem Phys ; 130(20): 204504, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19485454

RESUMO

X-band electron spin resonance (ESR) spectra of S(3)(-) radicals in ultramarine analog (pigment) prepared from zeolite A and maintaining the original structure of parent zeolite were recorded in the temperature range of 4.2-380 K. Electron spin echo experiments (echo detected ESR, electron spin-lattice relaxation, and spin echo dephasing) were performed in the temperature range of 4.2-50 K. The rigid lattice g factors are g(x) = 2.0016, g(y) = 2.0505, and g(z) = 2.0355, and they are gradually averaged with temperature to the final collapse into a single line with g = 2.028 above 300 K. This is due to reorientations of S(3)(-) molecule between 12 possible orientations in the sodalite cage through the energy barrier of 2.4 kJ/mol. The low-lying orbital states of the open form of S(3)(-) molecule having C(2v) symmetry are considered and molecular orbital (MO) theory of the g factors is presented. The orbital mixing coefficients were calculated from experimental g factors and available theoretical orbital splitting. They indicate that the unpaired electron spin density in the ground state is localized mainly (about 50%) on the central sulfur atom of S(3)(-) anion radical, whereas in the excited electronic state the density is localized mainly on the lateral sulfur atoms (90%). A strong broadening of the ESR lines in directions around the twofold symmetry axis of the radical S(3)(-) molecule (z-axis) is discovered below 10 K. It is due to a distribution of the S-S-S bond angle value influencing mainly the energy of the (2)B(2)-symmetry MO. This effect is smeared out by molecular dynamics at higher temperatures. A distribution of the g factors is confirmed by the recovery of the spin system magnetization during spin-lattice relaxation measurements, which is described by a stretched exponential function. Both the spin-lattice relaxation and electron spin echo dephasing are governed by localized phonon mode of energy of about 40 cm(-1). Thus, the anion-radical S(3)(-) molecules are weakly bonded to the zeolite framework, and they do not participate in the phonon motion of the host lattice because of their own local dynamics.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 69(5): 1395-404, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18060830

RESUMO

The aim of the work was to collect information concerning boundary effects which are suspected in alpha-alanine dosimeters consisted of powdered microcrystalline alpha-alanine and binders. In our experiments the conventional binders were replaced by molecular sieves (MS). MS are inorganic porous materials (host structures) with well organized and uniform intra-crystalline pore systems of nano-scale size. The guest molecules can be either physically adsorbed on very large inner MS surface, or chemically bound to the active sites. They can be also encapsulated inside the intracrystalline cavities. The EPR spectra of gamma irradiated DL-alpha-alanine supported on NaY, CeY, SOD, mordenite, ZSM-5 and ALPO(4)-5 were very similar to that one observed for irradiated microcrystalline DL-alpha-alanine. In the case of alanine supported on HY an initial EPR spectrum was different and only after some weeks it made resemble to the well known quintet observed in microcrystalline samples. In sodalites synthesized in the presence of DL-alpha-alanine EPR signal appeared in non-irradiated sample was very low and structureless. The irradiated sample showed a distinct spectrum which was quite different from that one observed for crystalline DL-alpha-alanine.


Assuntos
Alanina/efeitos da radiação , Compostos de Alumínio/química , Raios gama , Silicatos de Alumínio/química , Espectroscopia de Ressonância de Spin Eletrônica , Etilaminas/química , Troca Iônica
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