Developing the railway transport sector is a challenging scientific,economic and social research topic starting with ensuring human security.The main topic that should be developed in that sense is the ballast stabili...Developing the railway transport sector is a challenging scientific,economic and social research topic starting with ensuring human security.The main topic that should be developed in that sense is the ballast stability and dynamical behaviour under external loading and environmental changes.This paper investigates the effect of particle size distribution and normal pressure on the mechanical response of a ballast bed.Grading curves of ballast layers with different sizes are illustrated to discuss their strength behaviour under various strains to deduce the significant effect on the direct shear performance of the ballast layer.Direct shear tests with different Particle Size Distribution(PSD)were reproduced using the Discrete Element Method(DEM).It is noticed that when the number of small-sized ballast increases,the shear strength and the friction angle increase to varying degrees under different normal pressures,with an average increase of 27%and 8%,respectively.When the number of large-sized ballast decreases,the shear strength and the friction angle decrease to varying degrees under different normal pressures,with an average decrease of 6%and 3%,respectively.展开更多
Carbonaceous mudstone is a potential embankment filler in mountainous regions with limited high-quality materials;however,its engineering performance in highway embankments under complex environmental conditions remai...Carbonaceous mudstone is a potential embankment filler in mountainous regions with limited high-quality materials;however,its engineering performance in highway embankments under complex environmental conditions remains poorly understood.This study aimed to investigate the mechanical properties and failure mechanisms of carbonaceous mudstone filler under different temperature-moisture coupled conditions.Triaxial shear tests were conducted under four temperaturemoisture coupled conditions:dry-heat to dry-cold(DHDC),wet-cold to wet-heat(WCWH),dry-cold to wet-heat(DCWH),and dry-heat to wet-cold(DHWC).The effects of these conditions on the strength characteristics,relative breakage ratio,failure mode,and microscopic morphology were examined.A segmented prediction model based on the DuncanChang model was applied to validate the experimental results under the DHWC condition.The failure mechanisms under different conditions were also analyzed.The results indicate that the degradation of carbonaceous mudstone increases in the following order:DHDC,WCWH,DCWH,and DHWC.Under the DHDC condition,the stress-strain curves exhibit strain-softening behavior,while other conditions show strain-hardening behavior,with peak deviatoric stress occurring at 2%and 4%axial strains,respectively.The shear strength decreases by up to 40%under the DHWC condition but remains nearly unchanged under the DHDC condition,showing a positive correlation with particle breakage.As the number of cycles increases,the failure surfaces gradually move downward.Higher confining pressure shifts failure mode from shear failure to shear slip or localized compression,and eventually to overall compression or expansion failure.The modified Duncan-Chang model accurately predicts the experimental results.These findings provide important guidance for the application of carbonaceous mudstone filler in highway embankment construction in humid mountainous regions.展开更多
This study investigates laminar convection in three regimes(forced convection,mixed convection,and natural convection)of a bi-nanofluid(Cu-Al_(2)O_(3)-water)/mono-nanofluid(Al_(2)O_(3)-water)inside a square enclosure ...This study investigates laminar convection in three regimes(forced convection,mixed convection,and natural convection)of a bi-nanofluid(Cu-Al_(2)O_(3)-water)/mono-nanofluid(Al_(2)O_(3)-water)inside a square enclosure of sliding vertical walls which are kept at cold temperature and moving up,down,or in opposite directions.The enclosure bottom is heated partially by a central heat source of various sizes while the horizontal walls are considered adiabatic.The thermal conductivity and dynamic viscosity are dependent on temperature and nanoparticle size.The conservation equations are implemented in the solver ANSYS R2(2020).The numerical predictions are successfully validated by comparison with data from the literature.Numerical simulations are carried out for various volume fractions of solid mono/hybrid-nanoparticles(0≤ϕ≤5%),Richardson numbers(0.001≤Ri≤10),and hot source lengths((1/5)H≤ε≤(4/5)H).Isothermal lines,streamlines,and average Nusselt numbers are analyzed.The thermal performance of nanofluids is compared to that of the base heat transfer fluid(water).Outcomes illustrate the flow characteristics significantly affected by the convection regime,hot source size,sidewall motion,and concentration of solid nanoparticles.In the case of sidewalls moving downward,using hybrid nanofluid(Cu-Al_(2)O_(3)-water)shows the highest heat transfer rate in the enclosure at Ri=1,ε=(4/5)H and volume fraction ofφ=5%where a significant increment(25.14%)of Nusselt number is obtained.展开更多
Intrauterine insemination with donor sperm(IUI-D)is an assisted reproductive technology(ART)offered to couples with definitive male infertility or risk of genetic disease transmission.Here,we sought to evaluate our pr...Intrauterine insemination with donor sperm(IUI-D)is an assisted reproductive technology(ART)offered to couples with definitive male infertility or risk of genetic disease transmission.Here,we sought to evaluate our practice in IUI-D and identify factors that influenced the success rate.We performed a retrospective,single-center study of all IUI-D procedures performed at Lille University Medical Center(Lille,France)between January 1,2007,and December 31,2017.Single and multivariate analyses with a mixed logistic model were used to identify factors associated with clinical pregnancies and live births.We included 322 couples and 1179 IUI-D procedures.The clinical pregnancy rate was 23.5%,and the live birth rate was 18.9%per IUI-D.In a multivariate analysis,the women’s age was negatively associated with the live birth rate.The number of motile spermatozoa inseminated was the only factor associated with both clinical pregnancies and live births,with a chosen threshold of 0.75 million.The clinical pregnancy and live birth rates were,respectively,17.3%and 13.0%below the number of motile spermatozoa inseminated threshold and 25.9%and 21.0%at or above the threshold(all P=0.005).The number of motile spermatozoa inseminated was the only factor that significantly influenced both pregnancies and live-birth rates after IUI-D.Indeed,below a threshold of 0.75 million motile spermatozoa inseminated,those rates were significantly lower.Application of this number of motile spermatozoa inseminated threshold may help centers to allocate donations more effectively while maintaining reasonable waiting times for patients.展开更多
We successfully perform the three-dimensional tracking in a turbulent fluid flow of small axisymmetrical particles that are neutrally-buoyant and bottom-heavy,i.e.,they have a non-homogeneous mass distribu-tion along ...We successfully perform the three-dimensional tracking in a turbulent fluid flow of small axisymmetrical particles that are neutrally-buoyant and bottom-heavy,i.e.,they have a non-homogeneous mass distribu-tion along their symmetry axis.We experimentally show how a tiny mass inhomogeneity can affect the particle orientation along the preferred vertical direction and modify its tumbling rate.The experiment is complemented by a series of simulations based on realistic Navier-Stokes turbulence and on a point-like particle model that is capable to explore the full range of parameter space characterized by the gravi-tational torque stability number and by the particle aspect ratio.We propose a theoretical perturbative prediction valid in the high bottom-heaviness regime that agrees well with the observed preferential ori-entation and tumbling rate of the particles.We also show that the heavy-tail shape of the probability distribution function of the tumbling rate is weakly affected by the bottom-heaviness of the particles.展开更多
BACKGROUND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after surgery.Adherent-invasive Escherichia coli(AIEC)typified by the LF82 strain are pa...BACKGROUND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after surgery.Adherent-invasive Escherichia coli(AIEC)typified by the LF82 strain are pathobionts that are frequently detected in POR of Crohn's disease and have a potential role in the early stages of the disease pathogenesis.Saccharomyces cerevisiae CNCM I-3856 is a probiotic yeast reported to inhibit AIEC adhesion to intestinal epithelial cells and to favor their elimination from the gut.AIM To evaluate the efficacy of CNCM I-3856 in preventing POR induced by LF82 in an HLA-B27 transgenic(TgB27)rat model.METHODS Sixty-four rats[strain F344,38 TgB27,26 control non-Tg(nTg)]underwent an ICR at the 12th wk(W12)of life and were sacrificed at the 18th wk(W18)of life.TgB27 rats were challenged daily with oral administration of LF82(109 colony forming units(CFUs)/day(d),n=8),PBS(n=5),CNCM I-3856(109 CFUs/d,n=7)or a combination of LF82 and CNCM I-3856(n=18).nTg rats receiving LF82(n=5),PBS(n=5),CNCM I-3856(n=7)or CNCM I-3856 and LF82(n=9)under the same conditions were used as controls.POR was analyzed using macroscopic(from 0 to 4)and histologic(from 0 to 6)scores.Luminal LF82 quantifications were performed weekly for each animal.Adherent LF82 and inflammatory/regulatory cytokines were quantified in biopsies at W12 and W18.Data are expressed as the median with the interquartile range.RESULTS nTg animals did not develop POR.A total of 7/8(87%)of the TgB27 rats receiving LF82 alone had POR(macroscopic score≥2),which was significantly prevented by CNCM I-3856 administration[6/18(33%)TgB27 rats,P=0.01].Macroscopic lesions were located 2 cm above the anastomosis in the TgB27 rats receiving LF82 alone and consisted of ulcerations with a score of 3.5(2-4).Seven out of 18 TgB27 rats(39%)receiving CNCM I-3856 and LF82 had no macroscopic lesions.Compared to untreated TgB27 animals receiving LF82 alone,coadministration of CNCM I-3856 and LF82 significantly reduced the macroscopic[3.5(2-4)vs 1(0-3),P=0.002]and histological lesions by more than 50%[4.5(3.3-5.8)vs 2(1.3-3),P=0.003].The levels of adherent LF82 were correlated with anastomotic macroscopic scores in TgB27 rats(r=0.49,P=0.006),with a higher risk of POR in animals having high levels of luminal LF82(71.4%vs 25%,P=0.02).Administration of CNCM I-3856 significantly reduced the levels of luminal and adherent LF82,increased the production of interleukin(IL)-10 and decreased the production of IL-23 and IL-17 in TgB27 rats.CONCLUSION In a reliable model of POR induced by LF82 in TgB27 rats,CNCM I-3856 prevents macroscopic POR by decreasing LF82 infection and gut inflammation.展开更多
BACKGROUND Irritable bowel syndrome(IBS)is one of the most frequent and debilitating conditions leading to gastroenterological referrals.However,recommended treatments remain limited,yielding only limited therapeutic ...BACKGROUND Irritable bowel syndrome(IBS)is one of the most frequent and debilitating conditions leading to gastroenterological referrals.However,recommended treatments remain limited,yielding only limited therapeutic gains.Chitin-glucan(CG)is a novel dietary prebiotic classically used in humans at a dosage of 1.5-3.0 g/d and is considered a safe food ingredient by the European Food Safety Authority.To provide an alternative approach to managing patients with IBS,we performed preclinical molecular,cellular,and animal studies to evaluate the role of chitin-glucan in the main pathophysiological mechanisms involved in IBS.AIM To evaluate the roles of CG in visceral analgesia,intestinal inflammation,barrier function,and to develop computational molecular models.METHODS Visceral pain was recorded through colorectal distension(CRD)in a model of long-lasting colon hypersensitivity induced by an intra-rectal administration of TNBS[15 milligrams(mg)/kilogram(kg)]in 33 Sprague-Dawley rats.Intracolonic pressure was regularly assessed during the 9 wk-experiment(weeks 0,3,5,and 7)in animals receiving CG(n=14)at a human equivalent dose(HED)of 1.5 g/d or 3.0 g/d and compared to negative control(tap water,n=11)and positive control(phloroglucinol at 1.5 g/d HED,n=8)groups.The anti-inflammatory effect of CG was evaluated using clinical and histological scores in 30 C57bl6 male mice with colitis induced by dextran sodium sulfate(DSS)administered in their drinking water during 14 d.HT-29 cells under basal conditions and after stimulation with lipopolysaccharide(LPS)were treated with CG to evaluate changes in pathways related to analgesia μ-opioid receptor(MOR),cannabinoid receptor 2(CB2),peroxisome proliferator-activated receptor alpha,inflammation[interleukin(IL)-10,IL-1b,and IL-8]and barrier function[mucin 2-5AC,claudin-2,zonula occludens(ZO)-1,ZO-2]using the real-time PCR method.Molecular modelling of CG,LPS,lipoteichoic acid(LTA),and phospholipomannan(PLM)was developed,and the ability of CG to chelate microbial pathogenic lipids was evaluated by docking and molecular dynamics simulations.Data were expressed as the mean±SEM.RESULTS Daily CG orally-administered to rats or mice was well tolerated without including diarrhea,visceral hypersensitivity,or inflammation,as evaluated at histological and molecular levels.In a model of CRD,CG at a dosage of 3 g/d HED significantly decreased visceral pain perception by 14%after 2 wk of administration(P<0.01)and reduced inflammation intensity by 50%,resulting in complete regeneration of the colonic mucosa in mice with DSS-induced colitis.To better reproduce the characteristics of visceral pain in patients with IBS,we then measured the therapeutic impact of CG in rats with TNBS-induced inflammation to long-lasting visceral hypersensitivity.CG at a dosage of 1.5 g/d HED decreased visceral pain perception by 20%five weeks after colitis induction(P<0.01).When the CG dosage was increased to 3.0 g/d HED,this analgesic effect surpassed that of the spasmolytic agent phloroglucinol,manifesting more rapidly within 3 wk and leading to a 50%inhibition of pain perception(P<0.0001).The underlying molecular mechanisms contributing to these analgesic and anti-inflammatory effects of CG involved,at least in part,a significant induction of MOR,CB2 receptor,and IL-10,as well as a significant decrease in pro-inflammatory cytokines IL-1b and IL-8.CG also significantly upregulated barrier-related genes including muc5AC,claudin-2,and ZO-2.Molecular modelling of CG revealed a new property of the molecule as a chelator of microbial pathogenic lipids,sequestering gram-negative LPS and gram-positive LTA bacterial toxins,as well as PLM in fungi at the lowesr energy conformations.CONCLUSION CG decreased visceral perception and intestinal inflammation through master gene regulation and direct binding of microbial products,suggesting that CG may constitute a new therapeutic strategy for patients with IBS or IBSlike symptoms.展开更多
Micropropagation from shoot tips and nodal segments was carried out for the conservation and domestication of spontaneous Moroccan thyme, <i><span style="font-family:Verdana;">Thymus broussonetii...Micropropagation from shoot tips and nodal segments was carried out for the conservation and domestication of spontaneous Moroccan thyme, <i><span style="font-family:Verdana;">Thymus broussonetii</span></i><i> </i><span style="font-family:Verdana;">Boiss. subsp. </span><i><span style="font-family:Verdana;">broussonetii</span></i><span style="font-family:Verdana;"> (endemic threatened). The mineral composition of the culture medium, as well as the succession of different growth regulators, influenced the </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> growth of this species. Sterilized achenes of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">were able to germinate on an agar medium containing Gautheret macronutrients with a rate of 25% and a degree of contamination of less than 4%. Shoot apices of 15-day seedlings (two cotyledon leaves) were cultivated on SD + 0.46 μM Kin medium and the explants obtained were transplanted every month. Six macronutrients (MS, B</span><sub><span style="font-family:Verdana;">5</span></sub><span style="font-family:Verdana;">, SH, SD, MS</span><sub><span style="font-family:Verdana;">m</span></sub> <span><span style="font-family:Verdana;">and N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K) were tested and N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K was chosen for the following experiments. Seven cytokinins (Kin, BAP, 2iP, DPU, adenine, Zeat and TDZ) at 0.46, 0.93 and 2.32 μM/l were evaluated and the addition of 0.93 μM adenine to N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K medium favored significantly the induction of buds and the elongation of explants. Three polyamines (putrescine, spermidine and spermine) at 2, 5, 10 and 20 μM/l were tested. A better multiplication of buds, shoots and roots was noted for N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K + 10 μM spermine. Cytokinin-auxin combinations led to better root multiplication and an increase in the number of buds a</span></span><span style="font-family:Verdana;">nd the length of explants, particularly for 0.46 μM Kin + 2.85 μM IAA. Acclimatization was successfully carried out using vitroplants developing a good root system. One month after the start of acclimatization, 97% of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">plantlets were healthy. Three months later, they were transplanted into larger pots. 100% of the acclimatized plants developed flowers in the 2</span><sup><span style="font-family:Verdana;">nd</span></sup><span style="font-family:Verdana;"> year between June and August. Re-initiation of the </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> culture was carried out from sterilized twig segments collected from the acclimatized plants of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">with 1 - 2 nodes on the medium N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K + 0.46 μM Kin, and 52.1% of the explants healthily proliferated. Finally, two micropropagation prototypes were developed: shoot tip culture from seedlings obtained after germination of achenes and node culture from acclimatized plants.</span>展开更多
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ...Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future.展开更多
A LES model is proposed to predict the dispersion of particles in the atmosphere in the context of Chemical,Biological,Radiological and Nuclear(CBRN)applications.The code relies on the Finite Element Method(FEM)for bo...A LES model is proposed to predict the dispersion of particles in the atmosphere in the context of Chemical,Biological,Radiological and Nuclear(CBRN)applications.The code relies on the Finite Element Method(FEM)for both the fluid and the dispersed solid phases.Starting from the Navier-Stokes equations and a general description of the FEM strategy,the Streamline Upwind Petrov-Galerkin(SUPG)method is formulated putting some emphasis on the related assembly matrix and stabilization coefficients.Then,the Variational Multiscale Method(VMS)is presented together with a detailed illustration of its algorithm and hierarchy of computational steps.It is demonstrated that the VMS can be considered as a more general version of the SUPG method.The final part of the work is used to assess the reliability of the implemented predictor/multicorrector solution strategy.展开更多
The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the fi...The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the field of pesticides to progress. The study carried out here concerns the evaluation of the potency of Bacillus amyloliquefaciens Bc2 and Trichoderma harzianum to fight against strawberry cultures infected with anthracnose (Fragaria × ananassa Duch.). The studies were carried out in the laboratory and in the field. The results indicate that B. amyloliquefaciens Bc2 and Trichoderma harzianum TR are effective for the biological control of anthracnose, gray mold and powdery mildew on strawberries grown in field conditions. The increase in plant size and the number of fruits produced with these control agents has also been observed.展开更多
Bacillus amyloliquefaciens Bc2 and Trichderma harzianum TR were used to evaluate their growth-promoting activity on cultivated strawberries, under laboratory and field conditions, and we have noticed that the percenta...Bacillus amyloliquefaciens Bc2 and Trichderma harzianum TR were used to evaluate their growth-promoting activity on cultivated strawberries, under laboratory and field conditions, and we have noticed that the percentage of achene germination is important for ones treated with TR (=97%) followed by those treated with Bc2 strain (=90%) and the control (=84%). Inoculations on field showed that on untreated soil with insecticide, TR is effective and allows the development of plants and extends the duration of flowering and fruiting. On treated soil, Bc2 clearly promotes the growth and development of strawberry seedlings and its role as plant growth promoting microorganisms has been proved.展开更多
Origanum elongatum (Bonnet) Emb. & Maire, is a medicinal, aromatic and endemic plant of Morocco, characterized by its pharmacological effects, and is commonly used for the production of essential oils and aromas, ...Origanum elongatum (Bonnet) Emb. & Maire, is a medicinal, aromatic and endemic plant of Morocco, characterized by its pharmacological effects, and is commonly used for the production of essential oils and aromas, resulting in high harvest and overexploitation pressure. This is why the present study aims to implement the in vitro micropropagation of Origanum elongatum for optimal vitroplant production. Six macroelements were tested (SH, SD, N30K, MS, MSm and B5) and the SD medium was selected for vegetative propagation of the explants. Seven cytokinins: adenine (Ad), N6-(2-Isopentenyl) adenine, zeatin (Zeat), kinetin (Kin), benzyladenine (BAP), 1,3-diphenylurea (DPU) and thidiazuron (TDZ) were then evaluated at five concentrations (0.44, 1.33, 2.22, 3.11 and 4.44 μM/L) on growth, development, budding, rooting and hyperhydricity. 0.44 μM Kin was selected and combined with three auxins: indole-3-acetic acid (IAA), indole-3-butyric acid (AIB), and 1-naphthaleneacetic acid (NAA) at four concentrations (1.14, 2.85, 4.56 and 6.27 μM/L) to improve rooting and association with 1.14 μM IAA was shown to be efficient for roots development. Different concentrations of gibberellic acid (0.29, 1.5, 2.60 and 2.89 μM/L), combined with 0.44 μM/L Kin and 1.14 μM/L IAA, were tested and 2.60 μM/L GA<sub>3</sub> gave maximum buds and shoots. Then, the combination of three polyamines at five concentrations (1.134, 3.402, 5.67, 7.938 and 11.34 μM/L) with 0.44 μM Kin and 1.14 μM/L IAA showed an increase in the number of buds and shoots for 7.938 μM/L putrescine and 3.402 μM/L spermine. Finally, seedlings with good foliar and root development were acclimatized.展开更多
Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ ...Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ derivatives. However, their chemical and physical properties can be modified by the mode of their extraction, storage and distribution. These modifications might negatively affect the nutritional quality of the oils. The goals of this study were to: sample different vegetable oils for cosmetic or dietary use marketed in Cameroon, and verify purity and oxidation states of each kind of oil through determination of its acidity, iodine, peroxide, saponification, refractive indexes and the conformity of the labeling. The carotene content, the level of polar components and specific absorbance were also determined. As the result, six oils namely palm, palm kernel, coconut, black cumin, peanut and shea butter were collected. Apart from labeling, chemicals and physicals parameters analyzed were generally in accordance with the Cameroonian and Codex Alimentarius standard. This study suggests that vegetable oils sampled in the Cameroonian market may not expose consumers to lipid oxidation products generating pathological oxidative stress and inflammation. However, efforts in application of existing standard need to be done as far as labeling are concerned.展开更多
Biological control of plant diseases makes extensive use of the antagonists. The effectiveness of the control depends on the choice of an effective antagonist strains from criteria of implying a good knowledge of biol...Biological control of plant diseases makes extensive use of the antagonists. The effectiveness of the control depends on the choice of an effective antagonist strains from criteria of implying a good knowledge of biological peculiarities of the material used. In this study, the antagonistic activities of nine isolates of Bacillus amyloliquefaciens and one isolate of Trichoderma harzianum were tested in vitro against seven strains of Colletotrichum acutatum, the causal agent of strawberry anthracnose. It was found that T. harzianum and B. amyloliquefaciens strains showed the ability to inhibit the mycelial growth of the pathogen by dual culture technique by more than 50 percent. The nonvolatile substances produced by the antagonists showed high inhibition percentages that are more than 99 percent, meanwhile their volatile compounds inhibited the mycelial growth of C. acutatum strains with low inhibition percentages starting from 30 percent except the substances produced by B. amyloliquefaciens Bc2 that showed a high inhibition percentage of more than 70 percent.展开更多
Within the consistent daily rhythm of human life,intervertebral discs endure a variety of complex loads beyond the influences of gravity and muscle forces,leading to significant morphological changes(in terms of volum...Within the consistent daily rhythm of human life,intervertebral discs endure a variety of complex loads beyond the influences of gravity and muscle forces,leading to significant morphological changes(in terms of volume,area,and height)as well as biomechanical alterations,including an increase in disc stiffness and a decrease in intradiscal pressure.Remarkably,the discs demonstrate an ability to regain their original morphological and biomechanical characteristics after a period of nocturnal rest.The preservation of normal disc function is critically dependent on this recovery phase,which serves to forestall premature disc degeneration.This phenomenon of disc recovery has been extensively documented through numerous in vivo studies employing advanced clinical techniques such as Magnetic Resonance Imaging(MRI),stadiometry,and intradiscal pressure measurement.However,the findings from in vitro studies present a more complex picture,with reports varying between full recovery and only partial recuperation of the disc properties.Moreover,research focusing on degenerated discs in vitro has shed light on the quantifiable impact of degeneration on the disc ability to recover.Fluid dynamics within the disc are considered a primary factor in recovery,yet the disc intricate multiscale structure and its viscoelastic properties also play key roles.These elements interact in complex ways to influence the recovery mechanism,particularly in relation to the overall health of the disc.The objective of this review is to collate,analyze,and critically evaluate the existing body of in vivo and in vitro research on this topic,providing a comprehensive understanding of disc recovery processes.Such understanding offers a blueprint for future advancements in medical treatments and bionic engineering solutions designed to mimic,support,and enhance the natural recovery processes of intervertebral discs.展开更多
This study aims to investigate the ability of an imidazolium biobased Zwitterionic Ionic Liquids(ZILs)in enhancing the phytoavailability of copper from garden(G)and vineyard(V)soils using the model plant ryegrass.Unco...This study aims to investigate the ability of an imidazolium biobased Zwitterionic Ionic Liquids(ZILs)in enhancing the phytoavailability of copper from garden(G)and vineyard(V)soils using the model plant ryegrass.Uncontaminated and artificially contaminated CuSO_(4) soils,unamended and ZIL-amended soil modalities were designed.The copper/ZIL molar ratio(1/4)introduced was rationally established based on molecular modeling and on the maximal copper concentration in artificially contaminated soil.Higher accumulation of copper in the shoots was detected for the uncontaminated and copper contaminated ZIL amended V soils(18.9 and 23.3 mg/kg,respectively)contrary to G soils together with a ZIL concentration of around 3%(W/W)detected by LC-MS analyses.These data evidenced a Cu-accumulation improvement of 38%and 66%compared to non-amended V soils(13.6 and 13.9 mg/kg respectively).ZIL would be mainly present under Cu(II)-ZIL_(4) complexes in the shoots.The impact on the chemical composition of shoot was also studied.The results show that depending on the soils modalitity,the presence of free copper and/or ZIL led to different chemical compositions in lignin and monomeric sugar contents.In the biorefinery context,performances of enzymatic hydrolysis of shoots were also related to the presence of both ZIL and copper under free or complex forms.Ecotoxicity assessment of the vineyard soil samples indicated that the quantity of copper and ZIL remaining in the soils had no significant toxicity.ZIL amendment in a copper-contaminated soil was demonstrated as being a promising way to promote the valorization of phytoremediation plants.展开更多
The present paper discusses the vibrational properties of the mixture gelucire-quercetin(from 1%to 5%)at room and body temperature.Quercetin is a flavonoid having beneficial properties:biological and antioxidant;it is...The present paper discusses the vibrational properties of the mixture gelucire-quercetin(from 1%to 5%)at room and body temperature.Quercetin is a flavonoid having beneficial properties:biological and antioxidant;it is used in many fields as food,cosmetic and especially pharmaceutics but its use as a drug is affected by its low solubility.The Gelucire 50/13 is used as sustained release matrix forming agent in pharmaceutical applications and it has demonstrated the ability to improve the dissolution as well as the absorption of poorly water-soluble drugs.The mixture Gelucire-quercetin was essentially studied by FTIR(Fourier transform infrared spectroscopy)and Raman spectroscopy.The behavior of these two molecules has been investigated in the spectral range 4000-0 cm-1 in Raman spectroscopy,and 4,000-600 cm-1 in FTIR.展开更多
During both hot and cold seasons,masonry walls play an important role in the thermal performance between the interior and the exterior of occupied spaces.It is thus essential to analyze the thermal behavior at the hol...During both hot and cold seasons,masonry walls play an important role in the thermal performance between the interior and the exterior of occupied spaces.It is thus essential to analyze the thermal behavior at the hollow block’s level in order to better understand the temperature and heat flux distribution in its structure and potentially limit as much as possible the heat transfer through the block.In this scope,this paper offers an experimental and numerical in-depth analysis of heat transfer phenomena inside a hollow block using a dedicated experimental setup including a well-insulated reference box and several thermocouples and fluxmeters distributed at the boundaries and inside the hollow block.The block was then numerically 3D modelled and simulated using COMSOL Multiphysics under the same conditions,properties,and dimensions as the experimentally tested block.The comparison between the numerical and experimental results provides very satisfactory results with relative difference of less than 4%for the computed thermal resistance.展开更多
基金"PSPC Régions n°2"("Projets Structurants des Pôles de Compétitivitéen région")funded by Conseil Régional Hauts-de-France and BPI.
文摘Developing the railway transport sector is a challenging scientific,economic and social research topic starting with ensuring human security.The main topic that should be developed in that sense is the ballast stability and dynamical behaviour under external loading and environmental changes.This paper investigates the effect of particle size distribution and normal pressure on the mechanical response of a ballast bed.Grading curves of ballast layers with different sizes are illustrated to discuss their strength behaviour under various strains to deduce the significant effect on the direct shear performance of the ballast layer.Direct shear tests with different Particle Size Distribution(PSD)were reproduced using the Discrete Element Method(DEM).It is noticed that when the number of small-sized ballast increases,the shear strength and the friction angle increase to varying degrees under different normal pressures,with an average increase of 27%and 8%,respectively.When the number of large-sized ballast decreases,the shear strength and the friction angle decrease to varying degrees under different normal pressures,with an average decrease of 6%and 3%,respectively.
基金the financial support by the National Natural Science Foundation of China(52378440,42477143)the Key Science and Technology Program in the Transportation Industry(2022-MS1-032,2022-MS5-125)+2 种基金the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20251302)the Science and Technology Innovation Program of Hunan Province(2024RC3166)the Guangxi Key Research and Development Program(AB23075184)。
文摘Carbonaceous mudstone is a potential embankment filler in mountainous regions with limited high-quality materials;however,its engineering performance in highway embankments under complex environmental conditions remains poorly understood.This study aimed to investigate the mechanical properties and failure mechanisms of carbonaceous mudstone filler under different temperature-moisture coupled conditions.Triaxial shear tests were conducted under four temperaturemoisture coupled conditions:dry-heat to dry-cold(DHDC),wet-cold to wet-heat(WCWH),dry-cold to wet-heat(DCWH),and dry-heat to wet-cold(DHWC).The effects of these conditions on the strength characteristics,relative breakage ratio,failure mode,and microscopic morphology were examined.A segmented prediction model based on the DuncanChang model was applied to validate the experimental results under the DHWC condition.The failure mechanisms under different conditions were also analyzed.The results indicate that the degradation of carbonaceous mudstone increases in the following order:DHDC,WCWH,DCWH,and DHWC.Under the DHDC condition,the stress-strain curves exhibit strain-softening behavior,while other conditions show strain-hardening behavior,with peak deviatoric stress occurring at 2%and 4%axial strains,respectively.The shear strength decreases by up to 40%under the DHWC condition but remains nearly unchanged under the DHDC condition,showing a positive correlation with particle breakage.As the number of cycles increases,the failure surfaces gradually move downward.Higher confining pressure shifts failure mode from shear failure to shear slip or localized compression,and eventually to overall compression or expansion failure.The modified Duncan-Chang model accurately predicts the experimental results.These findings provide important guidance for the application of carbonaceous mudstone filler in highway embankment construction in humid mountainous regions.
文摘This study investigates laminar convection in three regimes(forced convection,mixed convection,and natural convection)of a bi-nanofluid(Cu-Al_(2)O_(3)-water)/mono-nanofluid(Al_(2)O_(3)-water)inside a square enclosure of sliding vertical walls which are kept at cold temperature and moving up,down,or in opposite directions.The enclosure bottom is heated partially by a central heat source of various sizes while the horizontal walls are considered adiabatic.The thermal conductivity and dynamic viscosity are dependent on temperature and nanoparticle size.The conservation equations are implemented in the solver ANSYS R2(2020).The numerical predictions are successfully validated by comparison with data from the literature.Numerical simulations are carried out for various volume fractions of solid mono/hybrid-nanoparticles(0≤ϕ≤5%),Richardson numbers(0.001≤Ri≤10),and hot source lengths((1/5)H≤ε≤(4/5)H).Isothermal lines,streamlines,and average Nusselt numbers are analyzed.The thermal performance of nanofluids is compared to that of the base heat transfer fluid(water).Outcomes illustrate the flow characteristics significantly affected by the convection regime,hot source size,sidewall motion,and concentration of solid nanoparticles.In the case of sidewalls moving downward,using hybrid nanofluid(Cu-Al_(2)O_(3)-water)shows the highest heat transfer rate in the enclosure at Ri=1,ε=(4/5)H and volume fraction ofφ=5%where a significant increment(25.14%)of Nusselt number is obtained.
文摘Intrauterine insemination with donor sperm(IUI-D)is an assisted reproductive technology(ART)offered to couples with definitive male infertility or risk of genetic disease transmission.Here,we sought to evaluate our practice in IUI-D and identify factors that influenced the success rate.We performed a retrospective,single-center study of all IUI-D procedures performed at Lille University Medical Center(Lille,France)between January 1,2007,and December 31,2017.Single and multivariate analyses with a mixed logistic model were used to identify factors associated with clinical pregnancies and live births.We included 322 couples and 1179 IUI-D procedures.The clinical pregnancy rate was 23.5%,and the live birth rate was 18.9%per IUI-D.In a multivariate analysis,the women’s age was negatively associated with the live birth rate.The number of motile spermatozoa inseminated was the only factor associated with both clinical pregnancies and live births,with a chosen threshold of 0.75 million.The clinical pregnancy and live birth rates were,respectively,17.3%and 13.0%below the number of motile spermatozoa inseminated threshold and 25.9%and 21.0%at or above the threshold(all P=0.005).The number of motile spermatozoa inseminated was the only factor that significantly influenced both pregnancies and live-birth rates after IUI-D.Indeed,below a threshold of 0.75 million motile spermatozoa inseminated,those rates were significantly lower.Application of this number of motile spermatozoa inseminated threshold may help centers to allocate donations more effectively while maintaining reasonable waiting times for patients.
基金supported by the National Natural Science Foundation of China (Grant 11988102)
文摘We successfully perform the three-dimensional tracking in a turbulent fluid flow of small axisymmetrical particles that are neutrally-buoyant and bottom-heavy,i.e.,they have a non-homogeneous mass distribu-tion along their symmetry axis.We experimentally show how a tiny mass inhomogeneity can affect the particle orientation along the preferred vertical direction and modify its tumbling rate.The experiment is complemented by a series of simulations based on realistic Navier-Stokes turbulence and on a point-like particle model that is capable to explore the full range of parameter space characterized by the gravi-tational torque stability number and by the particle aspect ratio.We propose a theoretical perturbative prediction valid in the high bottom-heaviness regime that agrees well with the observed preferential ori-entation and tumbling rate of the particles.We also show that the heavy-tail shape of the probability distribution function of the tumbling rate is weakly affected by the bottom-heaviness of the particles.
基金the Foundation DigestScience for its help in the breeding of the HLA-B27 transgenic animals and Lesaffre Company for the provision of S.cerevisiae CNCM I-3856.
文摘BACKGROUND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after surgery.Adherent-invasive Escherichia coli(AIEC)typified by the LF82 strain are pathobionts that are frequently detected in POR of Crohn's disease and have a potential role in the early stages of the disease pathogenesis.Saccharomyces cerevisiae CNCM I-3856 is a probiotic yeast reported to inhibit AIEC adhesion to intestinal epithelial cells and to favor their elimination from the gut.AIM To evaluate the efficacy of CNCM I-3856 in preventing POR induced by LF82 in an HLA-B27 transgenic(TgB27)rat model.METHODS Sixty-four rats[strain F344,38 TgB27,26 control non-Tg(nTg)]underwent an ICR at the 12th wk(W12)of life and were sacrificed at the 18th wk(W18)of life.TgB27 rats were challenged daily with oral administration of LF82(109 colony forming units(CFUs)/day(d),n=8),PBS(n=5),CNCM I-3856(109 CFUs/d,n=7)or a combination of LF82 and CNCM I-3856(n=18).nTg rats receiving LF82(n=5),PBS(n=5),CNCM I-3856(n=7)or CNCM I-3856 and LF82(n=9)under the same conditions were used as controls.POR was analyzed using macroscopic(from 0 to 4)and histologic(from 0 to 6)scores.Luminal LF82 quantifications were performed weekly for each animal.Adherent LF82 and inflammatory/regulatory cytokines were quantified in biopsies at W12 and W18.Data are expressed as the median with the interquartile range.RESULTS nTg animals did not develop POR.A total of 7/8(87%)of the TgB27 rats receiving LF82 alone had POR(macroscopic score≥2),which was significantly prevented by CNCM I-3856 administration[6/18(33%)TgB27 rats,P=0.01].Macroscopic lesions were located 2 cm above the anastomosis in the TgB27 rats receiving LF82 alone and consisted of ulcerations with a score of 3.5(2-4).Seven out of 18 TgB27 rats(39%)receiving CNCM I-3856 and LF82 had no macroscopic lesions.Compared to untreated TgB27 animals receiving LF82 alone,coadministration of CNCM I-3856 and LF82 significantly reduced the macroscopic[3.5(2-4)vs 1(0-3),P=0.002]and histological lesions by more than 50%[4.5(3.3-5.8)vs 2(1.3-3),P=0.003].The levels of adherent LF82 were correlated with anastomotic macroscopic scores in TgB27 rats(r=0.49,P=0.006),with a higher risk of POR in animals having high levels of luminal LF82(71.4%vs 25%,P=0.02).Administration of CNCM I-3856 significantly reduced the levels of luminal and adherent LF82,increased the production of interleukin(IL)-10 and decreased the production of IL-23 and IL-17 in TgB27 rats.CONCLUSION In a reliable model of POR induced by LF82 in TgB27 rats,CNCM I-3856 prevents macroscopic POR by decreasing LF82 infection and gut inflammation.
基金Supported by the Service Public de Wallonie(SPW-EER,convention 8588,Belgium).
文摘BACKGROUND Irritable bowel syndrome(IBS)is one of the most frequent and debilitating conditions leading to gastroenterological referrals.However,recommended treatments remain limited,yielding only limited therapeutic gains.Chitin-glucan(CG)is a novel dietary prebiotic classically used in humans at a dosage of 1.5-3.0 g/d and is considered a safe food ingredient by the European Food Safety Authority.To provide an alternative approach to managing patients with IBS,we performed preclinical molecular,cellular,and animal studies to evaluate the role of chitin-glucan in the main pathophysiological mechanisms involved in IBS.AIM To evaluate the roles of CG in visceral analgesia,intestinal inflammation,barrier function,and to develop computational molecular models.METHODS Visceral pain was recorded through colorectal distension(CRD)in a model of long-lasting colon hypersensitivity induced by an intra-rectal administration of TNBS[15 milligrams(mg)/kilogram(kg)]in 33 Sprague-Dawley rats.Intracolonic pressure was regularly assessed during the 9 wk-experiment(weeks 0,3,5,and 7)in animals receiving CG(n=14)at a human equivalent dose(HED)of 1.5 g/d or 3.0 g/d and compared to negative control(tap water,n=11)and positive control(phloroglucinol at 1.5 g/d HED,n=8)groups.The anti-inflammatory effect of CG was evaluated using clinical and histological scores in 30 C57bl6 male mice with colitis induced by dextran sodium sulfate(DSS)administered in their drinking water during 14 d.HT-29 cells under basal conditions and after stimulation with lipopolysaccharide(LPS)were treated with CG to evaluate changes in pathways related to analgesia μ-opioid receptor(MOR),cannabinoid receptor 2(CB2),peroxisome proliferator-activated receptor alpha,inflammation[interleukin(IL)-10,IL-1b,and IL-8]and barrier function[mucin 2-5AC,claudin-2,zonula occludens(ZO)-1,ZO-2]using the real-time PCR method.Molecular modelling of CG,LPS,lipoteichoic acid(LTA),and phospholipomannan(PLM)was developed,and the ability of CG to chelate microbial pathogenic lipids was evaluated by docking and molecular dynamics simulations.Data were expressed as the mean±SEM.RESULTS Daily CG orally-administered to rats or mice was well tolerated without including diarrhea,visceral hypersensitivity,or inflammation,as evaluated at histological and molecular levels.In a model of CRD,CG at a dosage of 3 g/d HED significantly decreased visceral pain perception by 14%after 2 wk of administration(P<0.01)and reduced inflammation intensity by 50%,resulting in complete regeneration of the colonic mucosa in mice with DSS-induced colitis.To better reproduce the characteristics of visceral pain in patients with IBS,we then measured the therapeutic impact of CG in rats with TNBS-induced inflammation to long-lasting visceral hypersensitivity.CG at a dosage of 1.5 g/d HED decreased visceral pain perception by 20%five weeks after colitis induction(P<0.01).When the CG dosage was increased to 3.0 g/d HED,this analgesic effect surpassed that of the spasmolytic agent phloroglucinol,manifesting more rapidly within 3 wk and leading to a 50%inhibition of pain perception(P<0.0001).The underlying molecular mechanisms contributing to these analgesic and anti-inflammatory effects of CG involved,at least in part,a significant induction of MOR,CB2 receptor,and IL-10,as well as a significant decrease in pro-inflammatory cytokines IL-1b and IL-8.CG also significantly upregulated barrier-related genes including muc5AC,claudin-2,and ZO-2.Molecular modelling of CG revealed a new property of the molecule as a chelator of microbial pathogenic lipids,sequestering gram-negative LPS and gram-positive LTA bacterial toxins,as well as PLM in fungi at the lowesr energy conformations.CONCLUSION CG decreased visceral perception and intestinal inflammation through master gene regulation and direct binding of microbial products,suggesting that CG may constitute a new therapeutic strategy for patients with IBS or IBSlike symptoms.
文摘Micropropagation from shoot tips and nodal segments was carried out for the conservation and domestication of spontaneous Moroccan thyme, <i><span style="font-family:Verdana;">Thymus broussonetii</span></i><i> </i><span style="font-family:Verdana;">Boiss. subsp. </span><i><span style="font-family:Verdana;">broussonetii</span></i><span style="font-family:Verdana;"> (endemic threatened). The mineral composition of the culture medium, as well as the succession of different growth regulators, influenced the </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> growth of this species. Sterilized achenes of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">were able to germinate on an agar medium containing Gautheret macronutrients with a rate of 25% and a degree of contamination of less than 4%. Shoot apices of 15-day seedlings (two cotyledon leaves) were cultivated on SD + 0.46 μM Kin medium and the explants obtained were transplanted every month. Six macronutrients (MS, B</span><sub><span style="font-family:Verdana;">5</span></sub><span style="font-family:Verdana;">, SH, SD, MS</span><sub><span style="font-family:Verdana;">m</span></sub> <span><span style="font-family:Verdana;">and N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K) were tested and N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K was chosen for the following experiments. Seven cytokinins (Kin, BAP, 2iP, DPU, adenine, Zeat and TDZ) at 0.46, 0.93 and 2.32 μM/l were evaluated and the addition of 0.93 μM adenine to N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K medium favored significantly the induction of buds and the elongation of explants. Three polyamines (putrescine, spermidine and spermine) at 2, 5, 10 and 20 μM/l were tested. A better multiplication of buds, shoots and roots was noted for N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K + 10 μM spermine. Cytokinin-auxin combinations led to better root multiplication and an increase in the number of buds a</span></span><span style="font-family:Verdana;">nd the length of explants, particularly for 0.46 μM Kin + 2.85 μM IAA. Acclimatization was successfully carried out using vitroplants developing a good root system. One month after the start of acclimatization, 97% of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">plantlets were healthy. Three months later, they were transplanted into larger pots. 100% of the acclimatized plants developed flowers in the 2</span><sup><span style="font-family:Verdana;">nd</span></sup><span style="font-family:Verdana;"> year between June and August. Re-initiation of the </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> culture was carried out from sterilized twig segments collected from the acclimatized plants of </span><i><span style="font-family:Verdana;">T. broussonetii</span></i><i> </i><span style="font-family:Verdana;">with 1 - 2 nodes on the medium N</span><sub><span style="font-family:Verdana;">30</span></sub><span style="font-family:Verdana;">K + 0.46 μM Kin, and 52.1% of the explants healthily proliferated. Finally, two micropropagation prototypes were developed: shoot tip culture from seedlings obtained after germination of achenes and node culture from acclimatized plants.</span>
基金funded by the Czech University of Life Sciences Prague(Internal Grant Agency:A_03_22-43110/1312/3101)the Czech Science(GACR 21-27454S)。
文摘Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future.
基金The authors received the funding of the Royal Higher Institute for Defence(MSP16-06).
文摘A LES model is proposed to predict the dispersion of particles in the atmosphere in the context of Chemical,Biological,Radiological and Nuclear(CBRN)applications.The code relies on the Finite Element Method(FEM)for both the fluid and the dispersed solid phases.Starting from the Navier-Stokes equations and a general description of the FEM strategy,the Streamline Upwind Petrov-Galerkin(SUPG)method is formulated putting some emphasis on the related assembly matrix and stabilization coefficients.Then,the Variational Multiscale Method(VMS)is presented together with a detailed illustration of its algorithm and hierarchy of computational steps.It is demonstrated that the VMS can be considered as a more general version of the SUPG method.The final part of the work is used to assess the reliability of the implemented predictor/multicorrector solution strategy.
文摘The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the field of pesticides to progress. The study carried out here concerns the evaluation of the potency of Bacillus amyloliquefaciens Bc2 and Trichoderma harzianum to fight against strawberry cultures infected with anthracnose (Fragaria × ananassa Duch.). The studies were carried out in the laboratory and in the field. The results indicate that B. amyloliquefaciens Bc2 and Trichoderma harzianum TR are effective for the biological control of anthracnose, gray mold and powdery mildew on strawberries grown in field conditions. The increase in plant size and the number of fruits produced with these control agents has also been observed.
文摘Bacillus amyloliquefaciens Bc2 and Trichderma harzianum TR were used to evaluate their growth-promoting activity on cultivated strawberries, under laboratory and field conditions, and we have noticed that the percentage of achene germination is important for ones treated with TR (=97%) followed by those treated with Bc2 strain (=90%) and the control (=84%). Inoculations on field showed that on untreated soil with insecticide, TR is effective and allows the development of plants and extends the duration of flowering and fruiting. On treated soil, Bc2 clearly promotes the growth and development of strawberry seedlings and its role as plant growth promoting microorganisms has been proved.
文摘Origanum elongatum (Bonnet) Emb. & Maire, is a medicinal, aromatic and endemic plant of Morocco, characterized by its pharmacological effects, and is commonly used for the production of essential oils and aromas, resulting in high harvest and overexploitation pressure. This is why the present study aims to implement the in vitro micropropagation of Origanum elongatum for optimal vitroplant production. Six macroelements were tested (SH, SD, N30K, MS, MSm and B5) and the SD medium was selected for vegetative propagation of the explants. Seven cytokinins: adenine (Ad), N6-(2-Isopentenyl) adenine, zeatin (Zeat), kinetin (Kin), benzyladenine (BAP), 1,3-diphenylurea (DPU) and thidiazuron (TDZ) were then evaluated at five concentrations (0.44, 1.33, 2.22, 3.11 and 4.44 μM/L) on growth, development, budding, rooting and hyperhydricity. 0.44 μM Kin was selected and combined with three auxins: indole-3-acetic acid (IAA), indole-3-butyric acid (AIB), and 1-naphthaleneacetic acid (NAA) at four concentrations (1.14, 2.85, 4.56 and 6.27 μM/L) to improve rooting and association with 1.14 μM IAA was shown to be efficient for roots development. Different concentrations of gibberellic acid (0.29, 1.5, 2.60 and 2.89 μM/L), combined with 0.44 μM/L Kin and 1.14 μM/L IAA, were tested and 2.60 μM/L GA<sub>3</sub> gave maximum buds and shoots. Then, the combination of three polyamines at five concentrations (1.134, 3.402, 5.67, 7.938 and 11.34 μM/L) with 0.44 μM Kin and 1.14 μM/L IAA showed an increase in the number of buds and shoots for 7.938 μM/L putrescine and 3.402 μM/L spermine. Finally, seedlings with good foliar and root development were acclimatized.
文摘Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ derivatives. However, their chemical and physical properties can be modified by the mode of their extraction, storage and distribution. These modifications might negatively affect the nutritional quality of the oils. The goals of this study were to: sample different vegetable oils for cosmetic or dietary use marketed in Cameroon, and verify purity and oxidation states of each kind of oil through determination of its acidity, iodine, peroxide, saponification, refractive indexes and the conformity of the labeling. The carotene content, the level of polar components and specific absorbance were also determined. As the result, six oils namely palm, palm kernel, coconut, black cumin, peanut and shea butter were collected. Apart from labeling, chemicals and physicals parameters analyzed were generally in accordance with the Cameroonian and Codex Alimentarius standard. This study suggests that vegetable oils sampled in the Cameroonian market may not expose consumers to lipid oxidation products generating pathological oxidative stress and inflammation. However, efforts in application of existing standard need to be done as far as labeling are concerned.
文摘Biological control of plant diseases makes extensive use of the antagonists. The effectiveness of the control depends on the choice of an effective antagonist strains from criteria of implying a good knowledge of biological peculiarities of the material used. In this study, the antagonistic activities of nine isolates of Bacillus amyloliquefaciens and one isolate of Trichoderma harzianum were tested in vitro against seven strains of Colletotrichum acutatum, the causal agent of strawberry anthracnose. It was found that T. harzianum and B. amyloliquefaciens strains showed the ability to inhibit the mycelial growth of the pathogen by dual culture technique by more than 50 percent. The nonvolatile substances produced by the antagonists showed high inhibition percentages that are more than 99 percent, meanwhile their volatile compounds inhibited the mycelial growth of C. acutatum strains with low inhibition percentages starting from 30 percent except the substances produced by B. amyloliquefaciens Bc2 that showed a high inhibition percentage of more than 70 percent.
文摘Within the consistent daily rhythm of human life,intervertebral discs endure a variety of complex loads beyond the influences of gravity and muscle forces,leading to significant morphological changes(in terms of volume,area,and height)as well as biomechanical alterations,including an increase in disc stiffness and a decrease in intradiscal pressure.Remarkably,the discs demonstrate an ability to regain their original morphological and biomechanical characteristics after a period of nocturnal rest.The preservation of normal disc function is critically dependent on this recovery phase,which serves to forestall premature disc degeneration.This phenomenon of disc recovery has been extensively documented through numerous in vivo studies employing advanced clinical techniques such as Magnetic Resonance Imaging(MRI),stadiometry,and intradiscal pressure measurement.However,the findings from in vitro studies present a more complex picture,with reports varying between full recovery and only partial recuperation of the disc properties.Moreover,research focusing on degenerated discs in vitro has shed light on the quantifiable impact of degeneration on the disc ability to recover.Fluid dynamics within the disc are considered a primary factor in recovery,yet the disc intricate multiscale structure and its viscoelastic properties also play key roles.These elements interact in complex ways to influence the recovery mechanism,particularly in relation to the overall health of the disc.The objective of this review is to collate,analyze,and critically evaluate the existing body of in vivo and in vitro research on this topic,providing a comprehensive understanding of disc recovery processes.Such understanding offers a blueprint for future advancements in medical treatments and bionic engineering solutions designed to mimic,support,and enhance the natural recovery processes of intervertebral discs.
文摘This study aims to investigate the ability of an imidazolium biobased Zwitterionic Ionic Liquids(ZILs)in enhancing the phytoavailability of copper from garden(G)and vineyard(V)soils using the model plant ryegrass.Uncontaminated and artificially contaminated CuSO_(4) soils,unamended and ZIL-amended soil modalities were designed.The copper/ZIL molar ratio(1/4)introduced was rationally established based on molecular modeling and on the maximal copper concentration in artificially contaminated soil.Higher accumulation of copper in the shoots was detected for the uncontaminated and copper contaminated ZIL amended V soils(18.9 and 23.3 mg/kg,respectively)contrary to G soils together with a ZIL concentration of around 3%(W/W)detected by LC-MS analyses.These data evidenced a Cu-accumulation improvement of 38%and 66%compared to non-amended V soils(13.6 and 13.9 mg/kg respectively).ZIL would be mainly present under Cu(II)-ZIL_(4) complexes in the shoots.The impact on the chemical composition of shoot was also studied.The results show that depending on the soils modalitity,the presence of free copper and/or ZIL led to different chemical compositions in lignin and monomeric sugar contents.In the biorefinery context,performances of enzymatic hydrolysis of shoots were also related to the presence of both ZIL and copper under free or complex forms.Ecotoxicity assessment of the vineyard soil samples indicated that the quantity of copper and ZIL remaining in the soils had no significant toxicity.ZIL amendment in a copper-contaminated soil was demonstrated as being a promising way to promote the valorization of phytoremediation plants.
文摘The present paper discusses the vibrational properties of the mixture gelucire-quercetin(from 1%to 5%)at room and body temperature.Quercetin is a flavonoid having beneficial properties:biological and antioxidant;it is used in many fields as food,cosmetic and especially pharmaceutics but its use as a drug is affected by its low solubility.The Gelucire 50/13 is used as sustained release matrix forming agent in pharmaceutical applications and it has demonstrated the ability to improve the dissolution as well as the absorption of poorly water-soluble drugs.The mixture Gelucire-quercetin was essentially studied by FTIR(Fourier transform infrared spectroscopy)and Raman spectroscopy.The behavior of these two molecules has been investigated in the spectral range 4000-0 cm-1 in Raman spectroscopy,and 4,000-600 cm-1 in FTIR.
文摘During both hot and cold seasons,masonry walls play an important role in the thermal performance between the interior and the exterior of occupied spaces.It is thus essential to analyze the thermal behavior at the hollow block’s level in order to better understand the temperature and heat flux distribution in its structure and potentially limit as much as possible the heat transfer through the block.In this scope,this paper offers an experimental and numerical in-depth analysis of heat transfer phenomena inside a hollow block using a dedicated experimental setup including a well-insulated reference box and several thermocouples and fluxmeters distributed at the boundaries and inside the hollow block.The block was then numerically 3D modelled and simulated using COMSOL Multiphysics under the same conditions,properties,and dimensions as the experimentally tested block.The comparison between the numerical and experimental results provides very satisfactory results with relative difference of less than 4%for the computed thermal resistance.
