Showing papers by "Congrès International d'Architecture Moderne published in 2020"
TL;DR: ADSCs fulfill the general accepted criteria for cell-based therapies, but still need further investigations into their efficiency, taking into consideration the host-environment and patient-associated factors.
Abstract: Adipose tissue derived stem cells (ADSCs) are mesenchymal stem cells identified within subcutaneous tissue at the base of the hair follicle (dermal papilla cells), in the dermal sheets (dermal sheet cells), in interfollicular dermis, and in the hypodermis tissue. These cells are expected to play a major role in regulating skin regeneration and aging-associated morphologic disgraces and structural deficits. ADSCs are known to proliferate and differentiate into skin cells to repair damaged or dead cells, but also act by an autocrine and paracrine pathway to activate cell regeneration and the healing process. During wound healing, ADSCs have a great ability in migration to be recruited rapidly into wounded sites added to their differentiation towards dermal fibroblasts (DF), endothelial cells, and keratinocytes. Additionally, ADSCs and DFs are the major sources of the extracellular matrix (ECM) proteins involved in maintaining skin structure and function. Their interactions with skin cells are involved in regulating skin homeostasis and during healing. The evidence suggests that their secretomes ensure: (i) The change in macrophages inflammatory phenotype implicated in the inflammatory phase, (ii) the formation of new blood vessels, thus promoting angiogenesis by increasing endothelial cell differentiation and cell migration, and (iii) the formation of granulation tissues, skin cells, and ECM production, whereby proliferation and remodeling phases occur. These characteristics would be beneficial to therapeutic strategies in wound healing and skin aging and have driven more insights in many clinical investigations. Additionally, it was recently presented as the tool key in the new free-cell therapy in regenerative medicine. Nevertheless, ADSCs fulfill the general accepted criteria for cell-based therapies, but still need further investigations into their efficiency, taking into consideration the host-environment and patient-associated factors.
196 citations
TL;DR: Characterization data from this study will contribute to identify and develop potential recycling alternatives for a more sustainable municipal plastic waste management, which is recognized as a priority in the European Circular Economy Action Plan to use resources in a moreustainable way.
58 citations
24 Jun 2020
TL;DR: Early plant growth potential showed that quinoa seeds inoculated either with QA1 or QF11 displayed higher germination rates and increased seedling growth, and these findings support the use of QA 1 and QF 11 as potential biofertilizers.
Abstract: Plant growth-promoting rhizobacteria represent a promising solution to enhancing agricultural productivity Here, we screened phosphate solubilizing bacteria from the rhizospheric soil of Chenopodium quinoa Willd and assessed their plant-growth promoting rhizobacteria (PGPR) properties including production of indole-3-acetic acid (IAA), siderophores, hydrogen cyanide (HCN), ammonia and extracellular enzymes We also investigated their tolerance to salt stress and their capacity to form biofilms Two isolated strains, named QA1 and QF11, solubilized phosphate up to 346 mg/L, produced IAA up to 79531 µg/mL, and tolerated up to 2 M NaCl in vitro 16S rRNA and Cpn60 gene sequencing revealed that QA1 and QF11 belong to the genus Bacillus licheniformis and Enterobacter asburiae, respectively In vivo, early plant growth potential showed that quinoa seeds inoculated either with QA1 or QF11 displayed higher germination rates and increased seedling growth Under saline irrigation conditions, QA1 enhanced plant development/growth Inoculation with QA1 increased leaf chlorophyll content index, enhanced P and K+ uptake and decreased plant Na+ uptake Likewise, plants inoculated with QF11 strain accumulated more K+ and had reduced Na+ content Collectively, our findings support the use of QA1 and QF11 as potential biofertilizers
42 citations
TL;DR: The SLC25 family could be used for the development of novel points of attack for targeted cancer therapy as well as potential biomarkers for various cancers.
Abstract: The transfer of metabolites through the mitochondrial membranes is a vital process that is highly controlled and regulated by the inner membrane. A variety of metabolites, nucleotides, and cofactors are transported across the inner mitochondrial membrane (IMM) by a superfamily of membrane transporters which are known as the mitochondrial carrier family (MCF) or the solute carrier family 25 (SLC25 protein family). In humans, the MCF has 53 members encoded by nuclear genes. Members of the SLC25 family of transporters, which is the largest group of solute carriers, are also known as mitochondrial carriers (MCs). Because MCs are nuclear-coded proteins, they must be imported into the IMM. When compared with normal cells, the mitochondria of cancer cells exhibit significantly increased transmembrane potentials and a number of their transporters are altered. SLC25 members were identified as potential biomarkers for various cancers. The objective of this review is to summarize what is currently known about the involvement of mitochondrial SLC25 carriers in associated diseases. This review suggests that the SLC25 family could be used for the development of novel points of attack for targeted cancer therapy.
31 citations
TL;DR: The roles of ADSCs in the protection of cells by modulating inflammation and immunity are introduced, their potential therapeutic properties are developed, and they are developed.
Abstract: The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs is a major goal in repair medicine. Stem cells are classified by their potential to differentiate into functional cells. Compared with other sources, adipose-derived stem cells (ADSCs) have the advantage of being abundant and easy to obtain. ADSCs are considered to be tools for replacing, repairing, and regenerating dead or damaged cells. The capacity of ADSCs to maintain their properties depends on the balance of complex signals in their microenvironment. Their properties and the associated outcomes are in part regulated by reactive oxygen species, which mediate the oxidation-reduction state of cells as a secondary messenger. ADSC therapy has demonstrated beneficial effects, suggesting that secreted factors may provide protection. There is evidence that ADSCs secrete a number of cytokines, growth factors, and antioxidant factors into their microenvironment, thus regulating intracellular signaling pathways in neighboring cells. In this review, we introduce the roles of ADSCs in the protection of cells by modulating inflammation and immunity, and we develop their potential therapeutic properties.
29 citations
TL;DR: The validated SPE-GC-MS/MS method was successfully applied for the extraction and quantification of the target UV filters in different types of water samples, including lake, river, seawater and swimming pool waters.
27 citations
TL;DR: The antioxidant bioactive compounds present in these microgreen species reduced the proliferation of tumoral cells, showing lesser effects with broccoli microgreens, in line with their lower ascorbic acid content and total antioxidant capacity.
Abstract: The antiproliferative effect of the bioaccessible fractions (BFs) of four hydroponic Brassicaceae microgreens (broccoli, kale, mustard and radish) was evaluated on colon cancer Caco-2 cells vs. normal colon CCD18-Co cells after 24 h treatment with BFs diluted 1:10 v/v in cell culture medium. Their bioactivity was compared with the digestion blank, while the colon cancer chemotherapeutic drug 5-fluorouracil was used as a positive control. Cell viability (mitochondrial enzyme activity assay (MTT test) and Trypan blue test) and mechanisms related to antiproliferative activity (cell cycle, apoptosis/necrosis, mitochondrial membrane potential, reactive oxygen species (ROS) production, Ca2+ and glutathione (GSH) intracellular content) were studied. All microgreen BFs increased ROS and decreased GSH, altering the redox status and causing mitochondrial membrane dissipation followed by a general cell cycle arrest in G2/M and apoptotic cell death via a Ca2+-independent mechanism. As a result, the antioxidant bioactive compounds present in these microgreen species reduced the proliferation of tumoral cells (10 to 12.8% -MTT or 20 to 41.9% -Trypan blue), showing lesser effects with broccoli microgreens, in line with their lower ascorbic acid content and total antioxidant capacity. Therefore, the daily intake of microgreens within a balanced diet could be a preventive nutritional strategy to reduce the burden of chronic degenerative diseases such as colon cancer.
26 citations
TL;DR: In this article, the potential use of exosomes in biomedicine, as well as the limitations that preclude their wider application, are analyzed, along with their application as biomarkers and as therapeutic tools.
Abstract: Exosomes are lipid bilayer particles released from cells into their surrounding environment. These vesicles are mediators of near and long-distance intercellular communication and affect various aspects of cell biology. In addition to their biological function, they play an increasingly important role both in diagnosis and as therapeutic agents. In this paper, we review recent literature related to the molecular composition of exosomes, paying special attention to their role in pathogenesis, along with their application as biomarkers and as therapeutic tools. In this context, we analyze the potential use of exosomes in biomedicine, as well as the limitations that preclude their wider application.
26 citations
TL;DR: The expression profiles of inflammation-related genes analyzed in resident immune cells demonstrated that these cells have a strong ability to regenerate adult skin stem cells and to produce endogenous substances such as growth differentiation factor 11 (GDF11).
Abstract: Human skin is composed of three layers: the epidermis, the dermis, and the hypodermis. The epidermis has four major cell layers made up of keratinocytes in varying stages of progressive differentiation. Skin aging is a multi-factorial process that affects every phase of its biology and function. The expression profiles of inflammation-related genes analyzed in resident immune cells demonstrated that these cells have a strong ability to regenerate adult skin stem cells and to produce endogenous substances such as growth differentiation factor 11 (GDF11). GDF11 appears to be the key to progenitor proliferation and/or differentiation. The preservation of youthful phenotypes has been tied to the presence of GDF11 in different human tissues, and, in the skin, this factor inhibits inflammatory responses. The protective role of GDF11 depends on a multi-factorial process implicating various types of skin cells such as keratinocytes, fibroblasts and inflammatory cells. GDF11 should be further studied for the purpose of developing novel therapies for the treatment of skin diseases.
21 citations
TL;DR: The liquids resulting from pyrolysis of industrial plastic waste (IPW) and postconsumer colored and white plastic film waste (PCPW and PWPW) at the pilot scale (80 kg/h) were widely c...
Abstract: The liquids resulting from pyrolysis of industrial plastic waste (IPW) and postconsumer colored and white plastic film waste (PCPW and PWPW, respectively) at the pilot scale (80 kg/h) were widely c...
18 citations
TL;DR: The objective of this work was the development of a methodology capable of simultaneously determine 26 mycotoxins in mixed feed rations collected in 20 dairy farms, using a sample preparation methodology based on a combination of (d)SPE and QuEChERS extractions.
Abstract: The objective of this work was the development of a methodology capable of simultaneously determine 26 mycotoxins in mixed feed rations collected in 20 dairy farms. A sample preparation methodology based on a combination of (d)SPE and QuEChERS extractions was used. Liquid chromatography-high resolution mass spectrometry was employed for both identification and quantification purposes. To this respect, a powerful workflow based on data-independent acquisition, consisting of fragmenting all precursor ions entering the mass spectrometer in narrow m/z isolation windows (SWATH), was implemented. SWATH data file then contains all the information that would be acquired in a multitude of different experimental approaches in a single all-encompassing dataset. Analytical method performance was evaluated in terms of linearity, repeatability and matrix effect. Relative recoveries were also measured, giving values above 80% for most compounds. Matrix-matched calibration was carried out and enabled reaching the low ng mL-1 level for many mycotoxins. The observed matrix effect, in most cases suppressive, reached even values higher than 60%. The repeatability was also adequate, showing a relative standard deviation lower than 10%. All unified samples analyzed showed co-occurrence of two or more mycotoxins, recurrently zearalenone, fumonisin B1, and β-zearalenol, with an occurrence frequency ranging from 60% to 90%.
TL;DR: Qualitative investigations performed in research activities in the field of Multi-disciplinary Design and Optimization (MDO) for overall aircraft design in the EU funded research project AGILE are presented.
TL;DR: The use of CBPs seems to be a promising low-cost and ecofriendly alternative to be employed as sorbent in SPE techniques to extract fungicides from the aquatic environment.
TL;DR: In this paper, the authors compared the performance of different schemes with slow and detonation combustion and found that the PDE thrust is less than the ramjet thrust, starting from small supersonic flight Mach numbers, and the validity of this statement for multichambered PDEs is confirmed by time-dependent calculations.
Abstract: The ramjets of different schemes with slow and detonation combustion are compared. Steady and unsteady processes in these engines are described by simple models of gasdynamics and thermodynamics, detonation waves, air deceleration in air intakes, and combustion product acceleration in supersonic sections of nozzles. Within the framework of these models, at a fixed adiabatic exponent the characteristics of any engine depend on two parameters, namely, the flight Mach number and the dimensionless combustion heat of the combustible mixture. The comparison performed for all actual values of these parameters, together with an analysis of thermodynamic cycles and one-dimensional time-dependent calculations (for the engines with combustion in traveling detonation waves), confirmed the importance of taking the unsteady processes in combustors into account. The comparison made in this study is actual, due to frequent claims about a possible considerable increase in the thrust characteristics on replacement of ramjets with slow combustion under a constant pressure by engines with combustion in pulsed or rotating detonation waves (pulse-detonation engines (PDE) or rotating detonation engines (RDE)). Usually, these assertions are made on the basis of the comparison of the thermal efficiencies and specific thrusts and impulses calculated according to these values. In the case of unsteady flow in the combustor, the recalculation of the thrusts and impulses according to the thermal efficiency overestimates their values. The validity of this statement for multichambered PDEs is confirmed by time-dependent calculations. In the case of instantaneous opening and closing of the entrance into the detonation chambers and an instantaneous, without energy expenditures, detonation wave initiation, the PDE thrust is less than the ramjet thrust, starting from small supersonic flight Mach numbers. Analogous calculations for the RDEs are unjustified due to the passage into a rotating noninertial coordinate system.
TL;DR: Under the optimized conditions, the proposed FPSE-GC-MS/MS method was validated in terms of linearity, repeatability, reproducibility, accuracy and precision and applied to real water samples, revealing the presence of 11 out of the 17 target fungicides.
Abstract: A rapid environmental pollution screening and monitoring workflow based on fabric phase sorptive extraction-gas chromatography-tandem mass spectrometry (FPSE-GC-MS/MS) is proposed for the first time for the analysis of 17 widespread used fungicides (metalaxyl, cyprodinil, tolylfluanid, procymidone, folpet, fludioxonil, myclobutanil, kresoxim methyl, iprovalicarb, benalaxyl, trifloxystrobin, fenhexamid, tebuconazole, iprodione, pyraclostrobin, azoxystrobin and dimethomorph) in environmental waters. The most critical parameters affecting FPSE, such as sample volume, matrix pH, desorption solvent and time, and ionic strength were optimized by statistical design of experiment to obtain the highest extraction efficiency. Under the optimized conditions, the proposed FPSE-GC-MS/MS method was validated in terms of linearity, repeatability, reproducibility, accuracy and precision. To assess matrix effects, recovery studies were performed employing different water matrices including ultrapure, fountain, river, spring, and tap water at 4 different concentration levels (0.1, 0.5, 1 and 5 µg/L). Recoveries were quantitative with values ranging between 70-115%, and relative standard deviation values lower than 14%. Limits of quantification were at the low ng/L for all the target fungicides. Finally, the validated FPSE-GC-MS/MS method was applied to real water samples, revealing the presence of 11 out of the 17 target fungicides.
TL;DR: Both silages alone or in combination are viable options for SSDS, as there were no differences in performance, or in feeding costs or margins, and the cost of BLY silage was 8% less than BKO silage.
Abstract: High costs from external inputs in small-scale dairy systems (SSDS) and possible effects of climate change, require forage alternatives as silage for the dry season, from small-grain cereals that h...
04 Jun 2020
TL;DR: The dual contribution of SfGtr4 and SfPgdA to the pathogenicity and the regulation biofilm formation by S. flexneri was demonstrated here.
Abstract: Biofilm formation is a significant cause for the environmental persistence of foodborne pathogens. This phenomenon remains misunderstood in Shigella flexneri whose pathogenicity is mainly associated with the virulence plasmid pWR100. Sequence analysis of the latter predicts a putative lipopolysaccharides (LPS) glycosyltransferase (Gtr) encoded by Sfgtr4, which is the second gene of the SfpgdA-orf186-virK-msbB2 locus. We demonstrated here that purified SfGtr4 exhibited a Gtr activity in vitro by transferring glucose to lipid A. To establish the role of SfGtr4 in virulence, we generated a Sfgtr4 mutant and assessed its phenotype in vitro. Sfgtr4 mutant significantly reduced HeLa cells invasion without impairing type III effectors secretion, increased susceptibility to lysozyme degradation, and enhanced bacterial killing by polymorphonuclear neutrophils (PMNs). SfGtr4 is related to proteins required in biofilm formation. We established conditions whereby wild-type Shigella formed biofilm and revealed that its appearance was accelerated by the Sfgtr4 mutant. Additional phenotypical analysis revealed that single SfpdgA and double SfpgdA-Sfgtr4 mutants behaved similarly to Sfgtr4 mutant. Furthermore, a molecular interaction between SfGtr4 and SfPgdA was identified. In summary, the dual contribution of SfGtr4 and SfPgdA to the pathogenicity and the regulation biofilm formation by S. flexneri was demonstrated here.
TL;DR: In this article, the hypothesis that black-oat (Avena strigosa Schreb), either grazing regrowth or as first-cut silage in the dry season, is a forage option for small-scale dairy farmers in the highlands of Mexico was investigated.
Abstract: Small-scale dairy systems are important worldwide for local and national production, and an option to overcome poverty. Effects of climate change need forage options adapted to future scenarios. This research addressed the hypothesis that black-oat (Avena strigosa Schreb.), either grazing regrowth or as first-cut silage in the dry season, is a forage option for small-scale dairy farmers in the highlands of Mexico. Part I presents performance of crop and dairy cows. There were two experiments. Treatments in Experiment 1 were restricted grazing of black-oat regrowth (BKO), black-oat with red clover (Trifolium pratense L. ‘Kenland’) (BKC) or a multi-species pasture (MSP) of grasses and white clover (T. repens L.) Experiment 2 evaluated inclusion of 2.5 (T1), 5.0 (T2) or 7.5 (T3) kg DM cow-1 d-1 of black-oat silage. Nine Holstein cows were used in both experiments, organized in groups of three randomly allotted to treatment in multiple 3×3 Latin squares replicated three times. Cows received 4.6 kg DM d-1 concentrate. There were no differences (P > 0.05) in animal variables with mean milk yields of 10.8 and 15.2 kg cow-1 d-1, 37.7 and 30.0 g kg-1 milkfat, 31.1 and 32.5 g kg-1 milk protein, 512.3 and 482.2 kg live weight, and 2.6 and 2.5 body condition score, for Experiment 1 and 2 respectively. Grazing black oat regrowth was equivalent to grazing temperate pastures, and the performance of cows was independent of the amount of black oat silage supplied. Black oat is a forage resource for small-scale dairy systems for grazing and silage.
TL;DR: In this article, the impact of the synthesis conditions on the physico-chemical properties and on the surface reactivity of the prepared materials was examined. But the analysis of the interactions of the samples with respect to a protein model (Bovin Serum Albumin), evaluated under the same experimental conditions, revealed a fast-kinetic process for precipitated samples, compared to the crystals obtained by solid chemical reaction.
TL;DR: In this paper, a study assessed the trophic state of three lakes used as fish farms in the region of Junin-Peru, under different hydrological conditions.
Abstract: The study assessed the trophic state of three lakes used as fish farms in the region of Junin-Peru, under different hydrological conditions. Surface water samples were collected from three points at each lake in 2018 during the rainy (March-April) and dry (June-July) seasons. Total phosphorus, turbidity, and chlorophyll-a (Chl-a) were measured. Trophic indexes (TSI Chl-a, and TSI TP) were also computed. The water trophic state categorization was performed by adapting and calculating the Trophic State Index (TSI). The TSI (TP) classified the three lakes in both seasons (rainy and dry) as mesotrophic (30 < TSI ≤ 60). Pomacocha and Tipicocha were classified as eutropic (60 < TSI ≤ 90) in the two seasons according to TSI (Chl a), while Tranca Grande was classified as mesotrophic (also two seasons). The results for TSI showed a predominance of eutrophic and mesotrophic conditions in all lakes used as fish farms.
TL;DR: This study's results demonstrate, for the first time in Colombia, that traps are a useful tool for the surveillance and control of A. aegypti.
Abstract: In the past decade, new strategies have been developed to control the Aedes aegypti (Diptera: Culicidae) mosquito vector, as well as a broad range of arboviral agents. Vector control surveillance programmes in Puerto Rico and Australia have implemented the Centers for Disease Control and Prevention autocidal gravid ovitrap (AGO), which has had an impact on vector density and, consequently, the epidemiology of arboviral infections. Colombia intends to establish the AGO as a new tool for the surveillance and control of the A. aegypti vector. AGOs were evaluated in a hyperendemic area for dengue virus during an 8-week period in Villavicencio city, eastern Colombia. The results indicated that the AGOs detect a high density of A. aegypti, with positive results for these traps of over 80% and an average catch of six individuals per trap per week. Acceptance of AGOs in the community exceeded 95%, and adherence was around 89%. This study's results demonstrate, for the first time in Colombia, that traps are a useful tool for the surveillance of A. aegypti. Future studies must consider the implementation of AGOs in the region.
TL;DR: In this paper, the interaction of turbulent jets with the surrounding environment is analyzed on the basis of the results of measurements and numerical modeling, and it is shown that the mechanism of the effect of the jet on the surrounding environments is associated with a decrease in the static pressure in the jet.
Abstract: On the basis of the results of measurements and numerical modeling, the interaction of turbulent jets (swirling and without swirling) with the surrounding environment is analyzed. It is shown that the mechanism of the effect of the jet on the surrounding environment is associated with a decrease in the static pressure in the jet. The nature of the influx of the external medium into the jet is independent of the mechanism of the appearance of reduced pressure, and the kinetic energy of the jet is an energy source for the induced flow.
TL;DR: In this article, the stability of one-dimensional steady flows of an ideal (inviscid and non-heat-conducting) gas in channels of variable cross section with combustion in a structurally stable detonation wave is studied.
Abstract: The stability of one-dimensional steady flows of an ideal (inviscid and non-heat-conducting) gas in channels of variable cross section with combustion in a structurally stable detonation wave is studied. The detonation wave represents a discontinuity surface propagating normally to the axis of the channel. It was previously established that, in this formulation, steady flows with combustion in a Chapman–Jouguet detonation wave are always unstable, in contrast to combustion flows in an overcompressed detonation wave. The stability analysis of such flows is reduced to the numerical solution of an initial-boundary value problem describing the evolution of finite flow perturbations between the moving detonation wave and the minimal nozzle cross section (in the case of a sudden contraction) or the exit nozzle cross section. The problem is solved by applying a modified Godunov scheme of higher order accuracy. More specifically, a Riemann solver with switching (between the overcompressed and Chapman–Jouguet detonation waves) with an explicitly represented detonation wave is created. Examples of stable flows and flows collapsing due to large initial perturbations are given, and their dynamics with transitions to a Chapman–Jouguet detonation wave and back are computed.
TL;DR: In this paper, the problem of designing the contours of two-dimensional and axisymmetric bodies of minimum wave drag and maximum-thrust nozzles, such that flow past them can contain internal shocks, is considered within the ideal (inviscid and non-heat-conducting) gas model.
Abstract: The problems of designing the contours of two-dimensional and axisymmetric bodies of minimum wave drag and maximum-thrust nozzles, such that flow past them can contain internal shocks, are considered within the ideal (inviscid and non-heat-conducting) gas model. These shocks may occur in flows past internal breaks in the optimal contours or on intersection of characteristics of the same family proceeding from these breaks. The submerged shocks occurring in the latter case are named internal, if their initial points lie within the domain of determinacy of the flowed-over optimal contour region. Further downstream the domain of determinacy is bounded by the characteristic coming to the end point of this contour. The internal submerged shocks can appear, when the optimal contour includes an interval of an isobaric streamline. The appearance of internal breaks in the optimal contours is possible due to the reflection of the pressure waves induced by them from the bow shock (for body noses) or, as might be expected, from tangential discontinuities (for afterbodies). In the case of supersonic freestreams having a tangential discontinuity the search for optimal two-dimensional afterbodies with an internal concave break flowed-over with an oblique shock is performed using the direct method with the representation of the required contours by the Bernstein—Bezier curves, a genetic algorithm, and a rapid and accurate marching scheme for calculating steady supersonic flows. While the optimal two-dimensional afterbodies with a convex internal break designed earlier using the general method of Lagrange multipliers could be reliably reproduced using the above-mentioned method, the expected optimal configurations with a concave break and an internal shock were not found. Instead, optimal contours with centered compression and expansion waves with the common focus on a tangential discontinuity and an “external” oblique shock proceeding from it were discovered. Then the new “discontinuous shock-free” solutions were constructed in the exact formulation, within the framework of the method of indefinite control contours and the method of characteristics. The solutions are generalized to include the contours of the afterbodies of revolution and supersonic parts of nozzles. In the case of a uniform freestream the flow past optimal afterbodies never includes internal shocks.
TL;DR: In this paper, the authors evaluate fechas de corte and the use of aditivos sobre the calidad del ensilado de la planta entera de girasol.
Abstract: El objetivo fue evaluar fechas de corte y del uso de aditivos sobre la calidad del ensilado de la planta entera de girasol. La variedad forrajera (Rumbosol-91) se cosecho en las semanas 1, 3 y 5 post-floracion (F1, F2 y F3, respectivamente) y tratada con los siguientes aditivos: 1) 1.5 × 105 ufc de inoculante g -1 de forraje, a base de bacterias lacticas homofermentativas Enterococcus faecium , Pediococcus pentosaceus y Lactobacillus plantarum (INOC), 2) 3 ml kg -1 de forraje de una solucion al 85% de acido formico (FORM) y 3) sin aditivo (Testigo); siguiendo un diseno factorial 3x3 con cinco repeticiones. La produccion de efluente y las perdidas totales de materia seca (MS) se redujeron, desde 282 y 134 g kg -1 en F+1 hasta 96 y 87 g kg -1 en F+5 como resultado del alto contenido de humedad del forraje proxima a la floracion. El analisis NIRS de las muestras de ensilaje mostro que los contenidos de proteina, fibra y digestibilidad descendian significativamente con la madurez de la planta; la rapida acumulacion de aceite en la MS hizo que la concentracion energetica fuese superior en el estado fenologico mas avanzado. La calidad fermentativa de los ensilajes fue satisfactoria, independientemente del momento de corte y del uso de aditivo. Se concluye que es preferible el corte de la planta a las cinco semanas post-floracion, donde se espera una fermentacion aceptable sin necesidad de conservantes.
24 Mar 2020
TL;DR: In this paper, a hierarchical sequence of creep models of various degrees of complexity is suggested depending on the necessity of taking into account stage I. The results of experimental study of high-temperature creep obtained for different single-crystal superalloys are presented.
Abstract: Features of the creep process in single-crystal nickel-based superalloys are studied in a wide range of temperatures and holding time for different crystallographic orientations. The results of experimental study of high-temperature creep obtained for different single-crystal superalloys are presented. The dominance of stage III of creep is observed for considered temperature range and loads. Uniform creep models describing I, II, and III stages, are proposed taking into account damage accumulation based on the Norton – Bailey relations and power law of evolution for the scalar damage measure of Kachanov – Rabotnov. A hierarchical sequence of creep models of various degrees of complexity is suggested depending on the necessity of taking into account stage I. A material model including six constants is sufficient to describe stages II and III. Simultaneous accounting of all three stages of creep can be carried out using model with nine constants. The assumption on the absence of damage at the first stage leads to a material model with ten constants. The entered additional tenth parameter characterizes the duration of the first stage. Identification methods for the parameters of the introduced models based on using the least-squares method and Nedeler – Mead method for solving the problem of minimizing the error functional are proposed. The results of verification of the proposed inelastic deformation models are presented for various nickel-based single-crystal superalloys. The standard deviation between the experimental and computation results for all the proposed creep models does not exceed 10%. This allows us to recommend the developed approach for estimating the level of irreversible accumulated strains and durability of the structural elements made of single-crystal superalloys.
01 Jan 2020
30 Nov 2020
TL;DR: This article purports to describe the health and safety measures related to the prevention of the risk of COVID- 19 infection to health professionals in China and Morocco and seeks to present the psychological support measures for these agents in the two aforementioned countries.
Abstract: A novel virus has emerged to the world causing a new pandemic of respiratory infection. On February 2020, the World Health Organization named it Corona disease 2019. The emergence of this epidemic was first reported in Wuhan, China in late December 2019, before it spread to other countries. In response to this pandemic, the World Health Organization has stressed the need for strengthening health professionals worldwide. Indeed, adequate protective measures can help protect patients and staff from the transmission of a highly infectious disease.
Managing COVID-19 patients exposes healthcare professionals to the risk of contracting the disease and transmitting it to those around them. This risk is very high because of the mode of transmission of SARS-CoV-2, which is transmitted by inhalation, contact with droplets and infected surfaces which makes it a very contagious disease. Thus, adequate precautions in healthcare establishments can help mitigate this risk, such as adopting several protective measures including personal protective equipment. By the same vein, healthcare professionals run a high risk of anxiety, stress, depression and burnout when managing COVID-19 patients. Therefore, the protection of the mental health of these health workers also includes psychological support measures.
In this regard, this article purports to describe the health and safety measures related to the prevention of the risk of COVID-19 infection to health professionals in China and Morocco. On the other hand, it seeks to present the psychological support measures for these agents in the two aforementioned countries.