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1.
J Phys Condens Matter ; 34(21)2022 03 21.
Article in English | MEDLINE | ID: mdl-35234670

ABSTRACT

In recent years, biodiesel production has emerged as an option for renewable and green fuel generation due to the constant reduction of fossil fuel reservoirs. Biofuels as biodiesel also show valuable attributes, environmentally speaking, due to their low environmental impact, contributing to the achievement of sustainability. However, costs are not allowable for large-scale production. Thereby, several novel processes have been proposed (e.g., reactive distillation) to solve this issue. An inconvenience for the development of these processes is the little information in the literature about the critical properties of fatty acids, which are precursors of biodiesel. Determination of critical properties for fatty acids through experimentation is difficult. The reason is that fatty acids tend to self-associate (to dimerize) due to carboxylic groups presence through hydrogen bonds, and consequently, have higher boiling points than other compounds of similar molecular mass (e.g., hydrocarbons, esters). Therefore, alternative methods for this determination are required. One choice is the group-contribution method, which is based on the structure of the molecule; however, results can significantly vary among different group-contribution approaches. Another alternative (and the focus of this research) for the determination of these properties is molecular simulation techniques. In this work, the liquid-vapor equilibrium as a function of temperature and the surface tension of three pure fatty acids of long chain (linoleic, oleic, and palmitic acid) have been calculated. Simulations have been performed by molecular dynamics using the method of direct determination of phase coexistence with the software GROMACS; in which the transferable potentials for phase equilibria united atom forcefield (TraPPE-UA) have been implemented for these specific molecules. Orthobaric densities and surface tension values have been reported at temperatures near the critical point (from 650 K to 800 K). Critical properties (temperature, pressure, density) have been extrapolated from trajectories obtained in these simulations using scaling law relations. Critical properties for these compounds are not available experimentally, therefore, group contribution calculations from the literature were used as a reference. In this comparison, the palmitic acid properties calculated in this work, show the best agreement among the three substances investigated.


Subject(s)
Biofuels , Molecular Dynamics Simulation , Fatty Acids/chemistry , Gases , Palmitic Acids
3.
Gac. sanit. (Barc., Ed. impr.) ; 30(4): 296-299, jul.-ago. 2016. tab
Article in Spanish | IBECS | ID: ibc-154120

ABSTRACT

Objetivo: El Real Decreto de Troncalidad (RDT) plantea modificar la formación sanitaria especializada, estableciendo 24 meses de formación troncal común. El objetivo de este estudio es valorar su potencial impacto en la formación especializada de medicina preventiva y salud pública (MPSP) y en otras especialidades del tronco común médico (TCM). Métodos: Se analizaron los programas de las 21 especialidades del TCM, recogiendo los periodos de rotación recomendados por cada especialidad y consensuando la información entre tres observadores. El impacto formativo se calculó como el porcentaje de meses que cada especialidad debería modificar para adaptarse al periodo común. Resultados: MPSP (100%, 24 meses) es la especialidad en la cual el RDT tendrá más impacto. Medicina intensiva (0%, 0 meses) y oncología médica (17%, 4 meses) son las especialidades menos afectadas. Conclusiones: El RDT va a afectar de manera diferente a las especialidades del TCM. El RDT supondrá un replanteamiento completo de sus actividades y de las competencias de los profesionales de MPSP (AU)


Objective: The purpose of the Core Training Law (CTL) is to amend specialised medical training to include 24 months of common training. The aim of this study is to assess its potential impact on the Preventive Medicine and Public Health (PM&PH) training programme and other medical specialties. Method: The programmes of the 21 common medical specialties were analysed and the recommended training periods for each specialty collected, before the information was agreed upon by three observers. The training impact was calculated as the percentage of months that should be amended per specialty to adapt to the common training schedule. Results: The Preventive Medicine and Public Health training programme is the specialty most affected by the Core Training Law (100%, 24 months). Intensive medicine (0%, 0 months) and medical oncology (17%, 4 months) is the least affected. Conclusions: The CTL affects the common medical specialties in different ways and requires a complete reorganisation of the activities and competencies of PM&PH professionals (AU)


Subject(s)
Humans , Education, Medical/trends , Education, Medical, Continuing/legislation & jurisprudence , Preventive Medicine/education , Public Health/education , Specialization/legislation & jurisprudence , 51725/analysis , Health Evaluation , Internship and Residency
4.
Gac Sanit ; 30(4): 296-9, 2016.
Article in Spanish | MEDLINE | ID: mdl-27264971

ABSTRACT

OBJECTIVE: The purpose of the Core Training Law (CTL) is to amend specialised medical training to include 24 months of common training. The aim of this study is to assess its potential impact on the Preventive Medicine and Public Health (PM&PH) training programme and other medical specialties. METHOD: The programmes of the 21 common medical specialties were analysed and the recommended training periods for each specialty collected, before the information was agreed upon by three observers. The training impact was calculated as the percentage of months that should be amended per specialty to adapt to the common training schedule. RESULTS: The Preventive Medicine and Public Health training programme is the specialty most affected by the Core Training Law (100%, 24 months). Intensive medicine (0%, 0 months) and medical oncology (17%, 4 months) is the least affected. CONCLUSIONS: The CTL affects the common medical specialties in different ways and requires a complete reorganisation of the activities and competencies of PM&PH professionals.


Subject(s)
Education, Medical/legislation & jurisprudence , Legislation, Medical , Medicine , Preventive Medicine , Public Health , Humans , Internship and Residency , Preventive Medicine/education , Preventive Medicine/legislation & jurisprudence , Public Health/education , Public Health/legislation & jurisprudence , Spain
5.
Mycol Res ; 113(5): 552-8, 2009 May.
Article in English | MEDLINE | ID: mdl-19640403

ABSTRACT

Fruiting is a crucial developmental process in basidiomycetes yet the genetic and molecular factors that control it are not yet fully understood. The search for fruiting inducers is of major relevance for both basic research and for their use in industrial applications. In this paper, an efficient and reproducible protocol for controlled fruiting induction of Pleurotus ostreatus growing on synthetic medium is described. The protocol is based on the control of light intensity and photoperiod and permits the life cycle for this fungus to be completed in less than two weeks. The fruiting bodies produced by this method release fertile spores after 4-5 d of culture. Our results indicate that fruiting induction is solely dependent on the illumination regime and that it occurs long before the available nutrients are depleted in the culture. This protocol will greatly facilitate molecular and developmental biology research in this fungus as it avoids the need for complex culture media based on lignocellulosic materials or the use of chemical inducers.


Subject(s)
Fruiting Bodies, Fungal/growth & development , Lighting/methods , Pleurotus/growth & development , Fluorescence , Photoperiod , Spores, Fungal/growth & development
6.
Appl Opt ; 42(30): 5938-46, 2003 Oct 20.
Article in English | MEDLINE | ID: mdl-14594050

ABSTRACT

The spatial characterization of laser-induced plasmas, including their temperature, electron density, and relative atom density, has been carried out by emission spectroscopy. The plasmas were generated with iron samples in air and argon at atmospheric pressure. An imaging spectrometer equipped with an intensified CCD detector procured spectra with spatial resolution. The plasma characterization was made at three temporal gates (2-3, 5-6, and 9-11 micros) to permit the plasma's evolution to be studied. A deconvolution procedure was developed to transform the measured intensity, integrated along the line of sight, into the radial distribution of emissivity. Temperature and electron density distributions were obtained under the assumption of local thermodynamic equilibrium and Stark broadening of the emission lines. The relative atom density distributions in the plasma of the Fe atoms arising from the sample and of the Ar atoms arising from the ambient gas were determined and evidenced an important interaction between the plasma and the surrounding atmosphere.

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