Phase Behavior of strongly associating systems

The modeling of associating fluids has been an active area of research for several decades. Attention has gradually shifted from the so called chemical theories, where molecular association is treated as a chemical reaction, to molecular models where association naturally arises from strong attractive intermolecular forces; among the last ones the Statistical Associating Fluid Theory (SAFT) and related approaches are becoming very popular. We will present calculations performed with the soft-SAFT EoS [F.J. Blas and L.F. Vega, Ind. Eng. Chem. Res. 37 (1998) 660-674.] to simulate the equilibrium thermodynamic properties of the acetic acid and the nitriles family (two classes of strongly associating compounds) as well as their mixtures[K. Jackowski and E. Wielogorska, Journal of Molecular Structure355 (1995) 287-290.]. Carboxylic acids form stable double hydrogen bridged dimers which in the gas phase exist in equilibrium with the monomers. Molecular association in liquid phase of the nitriles family is interesting as they are important organic solvents which are soluble in water without any limits. Pure-component molecular parameters are obtained by fitting the equation to available experimental data. The equation enables to search for physical trends, allowing the transferability of the parameters. The complex behavior of these mixtures is also investigated with the same approach

Soft-SAFT modeling of vapour liquid equilibria of nitriles and their mixtures

Nitriles are strong polar compounds showing a highly non-ideal behavior, which makes them challenging systems from a modeling point of view; in spite of this, accurate predictions for the vapor-liquid equilibria of these systems are needed, as some of them, like acetonitrile (CH3CN) and propionitrile (C2H5CN), play an important role as organic solvents in several industrial processes. This work deals with the calculation of the vapor - liquid equilibria (VLE) of nitriles and their mixtures by using the crossover soft-SAFT Equation of State (EoS). Both polar and associating interactions are taken into account in a single association term in the crossover soft-SAFT equation, while the crossover term allows for accurate calculations both far from and close to the critical point. Molecular parameters for acetonitrile, propionitrile and n-butyronitrile (C3H7CN) are regressed from experimental data. Their transferability is tested by the calculation of the VLE of heavier linear nitriles, namely, valeronitrile (C4H9CN) and hexanonitrile (C5H11CN), not included in the fitting procedure. Crossover soft-SAFT results are in excellent agreement with experimental data for the whole range of thermodynamic conditions investigated, proving the robustness of the approach. Parameters transferability has also been used to describe the isomers n-butyronitrile and i-butyronitrile. Finally, the nitriles soft-SAFT model is further tested in VLE calculation of mixtures with benzene, carbon tetrachloride and carbon dioxide, which proved to be satisfactory as well

Competencies and training needs and its impact on determining the professional skills of Algerian elite coaches

The main purpose of this study is to develop an understanding of the trainers' perceptions of competency and training needs related to professional skills in accordance with professional experience and academic education. The sample included 76 judo trainers who answered a questionnaire that included a measure that focused on the perceptions of competency and another on training needs. An exploratory factor analysis was used with the maximum probability factor (Oblimin) to determine emerging factors. A comparison of the Coaches ' concepts was made in the training experience and the academic background of the Coaches, where multiple comparisons were applied using ANOVA and Tukey. Three main areas of skills were done: skills related to annual planning; skills related to practice and competition; and personal education and training skills. Coach es' perceptions of their expertise were affected, with low-level trainers classifying themselves at lower levels of efficiency and more training needs; and higher-education Coaches in physical education were more efficient than mid-level trainers. Finally, most trainers consider them as efficient as they have indicated the training needs to be provided, which brings important feedback to the education of trainers. This suggests that trainers are an increasing their knowledge and competence in a wide range of areas that should be considered in future training of trainers programs, also to ensure the quality of education and training in the different level of physical and sports education institutes of the Algerian universities

Peppermint (Mentha piperita L.) essential oil as a potent anti-inflammatory, wound healing and anti-nociceptive drug

The present investigation was designed to study the chemical composition of Algerian peppermint essential oil (PEO) as well as the in vitro and in vivo anti-inflammatory, wound-healing and anti-nociceptive properties. Twenty-three compounds were identified in the PEO with the main chemical component as menthol (53.29%). Also, PEO showed a high content of oxygenated monoterpene compounds (92.75%). Topical application of PEO at doses of 200 and 20 µL/kg significantly reduced the acute ear edema in 38.09% and 36.50, respectively. Histological observation confirmed that PEO inhibited the skin inflammatory response. In-vivo wound healing activity of the cream prepared from PEO (0.5% w/w) was assessed by circular excision wound model followed by histological examination. The topical administration of PEO cream showed a significant decrease of unhealed wound area rate between the 6th (1.67±0.14 mm2) and the 9th (0.49±0.22 mm2) days of treatment when compared with the vehicle (2.32±0.77 mm2; p<0.05) and Madecassol® 0.1% creams (2.23±0.35 mm2; p<0.05). The PEO reduced nociceptive behavior at all doses tested in the acetic acid-induced nociception test (p<0.05). These findings support the anti-inflammatory, wound-healing and analgesic properties of PEO. We suggest that PEO is a promising candidate for use in skin care products with anti-inflammatory and wound-healing properties. DOI: http://dx.doi.org/10.5281/zenodo.383104

The effects of circuit exercise training strategy on health-related physical fitness level and biomarkers in elderly people with cardiovascular diseases

This study investigated the effects of a 12-week circuit exercise training intervention on health-related physical fitness and biomarkers in elderly adults with cardiovascular diseases. A total of 69 participants underwent the circuit exercise training program, which included stretching, aerobic activity, and weight training. The results showed that the participants had improved performance in cardiovascular and strength tests, with grip and back muscle strength showing improvement. However, sit-ups were lower than the average, and power, reaction time, and agility needed more effort. The high sensitivity C-reactive protein value reached a medium infection risk level for cardiovascular illnesses. The study concluded that there was a strong association between health-related physical fitness and biomarker index in senior persons with a medium risk cluster of cardiovascular illnesses. The study also found that BMI correlated positively with biomarker index, while cardiovascular fitness, agility, and flexibility correlated negatively with biomarker index

Intelligent assistant system as a context-aware decision-making support for the workers of the future

International audienceThe key role of information and communication technologies (ICT) to improve manufacturing productivity within the paradigm of factory of the future is often proved. These tools are used in a wide range of product lifecycle activities, from the early design phase to product recycling. Generally, the assistance tools are mainly dedicated to the management board and fewer initiatives focus on the operational needs of the worker at the shop-floor level. This paper proposes a context-aware knowledge-based system dedicated to support the actors of the factory by the right information at the right time and in the appropriate format regarding their context of work and level of expertise. Particularly, specific assistance functionalities are dedicated to the workers in charge of the machine configuration and the realization of manufacturing operations. PGD-based (Proper Generalized Decomposition) algorithms are used for real time simulation of industrial processes and machine configuration. At the conceptual level, a semantic model is proposedas key enablersfor the structuration of the knowledge-based system

STUDY OF PERCEPTION OF PROFESSIONAL COMPETENCES IN TEACHERS IN RELATION TO THE REQUIREMENTS OF THE PROFESSION OF TEACHING PHYSICAL EDUCATION

The purpose of this study was to identify teachers' perceptions of competence and knowledge of pedagogical needs related to occupational skills based on professional experience and academic education. Participants were 85 secondary school teachers from several schools who responded to a questionnaire that included a first scale of competency perceptions and a second scale on the recognition of teaching needs. The comparison of teacher perceptions based on teaching experience and teachers experience was done by applying the one-way ANOVA and Tukey's multiple post hoc comparisons. Teachers' perceptions were influenced by their experience as less experienced teachers qualified at lower levels of competence and more teaching needs; Teachers with a higher education, whether in physical education or others, perceived themselves to be more competent than teachers without a higher education. Finally, the majority of teachers perceived themselves as competent, but nevertheless indicated that they had teaching needs, which brings important feedback to the teacher of the secondary trainer. This suggests that teachers are interested in increasing their knowledge and competence in a wide range of areas which should be considered in future Teachers education programs

Spearmint (Mentha spicata L.) essential oil from tipaza (Algeria): in vivo anti-infl ammatory and analgesic activities in experimental animal models

Introduction: Although analgesic and nonsteroidal anti-infl ammatory drugs (NSAIDs) are usually used to treat a diversity of illnesses, their administration is linked with acute kidney injury and gastrointestinal side eff ects. The research of new biomolecules and natural products is still needed such as medicinal plants. Aims: The present research was aimed to investigate, for the fi rst time, the anti-infl ammatory and anti-nociceptive eff ects of spearmint essential oil (SEO) in mouse models of acute infl ammation and pain. Materials and Method: Chemical analysis of SEO was done by gas chromatography. The anti-infl ammatory activity was tested using two models of acute infl ammation namely carrageenan-induced paw edema and xylene-induced ear edema. Histological examination of both non-infl amed and infl amed tissues was evaluated. The anti-nociceptive activity was tested using the pain model induced by acetic acid. Results: The main constituent of the SEO was found to be carvone (52.60%). The SEO exhibited a promising anti-infl ammatory eff ect as demonstrated by statistically signifi cant (p<0.05) inhibition of paw volume by 77.24% at the dose of 20 μL/kg and 65.87% at the dose of 200 μL/kg. Furthermore, topical administration of the SEO inhibited xylene-induced ear edema in comparison with the control group (p<0.05). The higher dose (200 μL /kg) signifi cantly (p<0.001) reduced xylene-induced ear edema which was similar to that observed with positive control (ketoprofen). The pathological analysis of the paws and ears revealed that SEO was capable of reducing cellular infi ltration and subcutaneous edema. Else, the SEO produced signifi cant anti-nociceptive activity (p<0.001) at higher dose by inhibiting spontaneous nociception. Conclusion: These results support the use of SEO in the development of pharmaceuticals for the management of infl ammation and pain

Melatonin as a new postharvest treatment for increasing cut carnation (Dianthus caryophyllus L.) vase life

The marketability of cut flowers is directly affected by their vase life, which determines acceptability for commercial purposes. In carnations and other species of cut flowers, corolla is one of the most affected parts during flower senescence due to the petal withering which is accelerated by metabolic processes occurring after separation from the mother plant. Melatonin (MT) is a compound with antioxidant properties, naturally present in plant tissues that plays important roles in the regulation of different metabolic processes. In this research work the effect of different MT concentrations (0.01, 0.1 and 1 mM) on the vase life of cut carnations flowers cv. Baltico was evaluated. The greatest delay in senescence was observed with 0.1 mM MT concentration, increasing vase life up to 10 days more as compared to control carnations. Although all MT concentrations assayed significantly (P < 0.05) maintained initial levels of fresh weight, membrane stability index, bioactive compounds and antioxidant activity for longer time, the lowest concentrations were those that had the most relevant impact on vase life. The highest dose evaluated (1 mM) maintained all the parameters evaluated but showed the wilting symptoms earlier. For this reason, 0.1 MT concentration could be a tool capable of improving carnation vase life for longer time, increasing the commercial potential of this cut flower