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
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
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
BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel habits...BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel habits.First-line recommended treatments are limited to combining drugs targeting predominant symptoms,particularly pain(antispasmodics),constipation(laxatives),and diarrhea(loperamide),yielding only a limited therapeutic gain.GASTRAP^(■)DIRECT is a class IIa medical formulation composed of a combination of chitin-glucan and simethicone indicated for the symptomatic treatment of gas-related gastrointestinal disorders by combining different mechanisms of action.AIM To evaluate the efficacy,tolerability,and safety of 4-week GASTRAP^(■)DIRECT treatment in patients with IBS.METHODS In this prospective,multicenter,open-label trial,120 patients with IBS received three sticks of GASTRAP^(■)DIRECT(1.5 g/d of chitin-glucan and 0.75 mg/d of simethicone)per day for 4 weeks.The primary endpoint was the responder rate,defined as the number of patients whose abdominal pain score decreased by≥30%from baseline to week(W)4.The analysis was performed using the per-protocol set.Cardinal symptoms,impact of global symptoms on daily life,change in stool consistency,and improvement in defecatory disorders were evaluated.RESULTS Overall,100 patients were evaluated.At W4,67%(95%CI:57-75)showed improvement in abdominal pain(score:5.8±2.4 vs 2.9±2.0,P<0.0001).Similar improvements were observed for bloating[8.0±1.7 vs 4.7±2.9,P<0.0001;60%(95%CI:50-70)responders],abdominal distension[7.2±2.1 vs 4.4±3.1,P<0.0001;53%(95%CI:43-63)responders],and impact of global symptoms on daily life[7.1±2.0 vs 4.6±2.9,P<0.0001;54%(95%CI:44-64)responders].Stool consistency improved in most patients(90%and 57%for patients with liquid and hard stools,respectively).Overall,42%of patients with defecatory disorders reported very much/considerable improvements by W2.No severe adverse event occurred,and tolerability was rated“good”or“very good”by 93%of patients.CONCLUSION GASTRAP^(■)DIRECT is safe and well tolerated,alleviating IBS symptoms rapidly in 2 weeks.This open-label study suggests that the combination of chitin-glucan and simethicone could be beneficial in patients with IBS.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
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
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
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
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
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
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
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
Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable con...Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.展开更多
The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Ba...The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Bacillus amyloliquefaciens. The efficacy of isolates was tested, at different concentrations. Results showed that one Bacillus isolates (Bc2) and TR were more effective at the lower concentration tested (3 × 105 CFU/ml and 105 conidia/ml).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
Background Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)is responsible for an important mortality rate worldwide.We aimed to evaluate the actual imputability of SARS-CoV-2 on the mortality rate associate...Background Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)is responsible for an important mortality rate worldwide.We aimed to evaluate the actual imputability of SARS-CoV-2 on the mortality rate associated with SARS-CoV-2-related illnesses in the pediatric intensive care unit(PICU).Secondary objectives were to identify risk factors for death.Methods This national multicenter comparative study comprised all patients under 18 years old with positive SARS-CoV-2 polymerase chain reactions(PCRs)[acute corona virus disease 2019(COVID-19)or incidental SARS-CoV-2 infection]and/or pediatric inflammatory multisystem syndrome(PIMS)recorded in the French PICU registry(PICURe)between September 1,2021,and August 31,2022.Included patients were classified and compared according to their living status at the end of their PICU stay.Deceased patients were evaluated by four experts in the field of pediatric infectiology and/or pediatric intensive care.The imputability of SARS-CoV-2 as the cause of death was classified into four categories:certain,very probable,possible,or unlikely,and was defined by any of the first three categories.Results There were 948 patients included of which 43 died(4.5%).From this,26 deaths(67%)could be attributed to SARS-CoV-2 infection,with an overall mortality rate of 2.8%.The imputability of death to SARS-CoV-2 was considered certain in only one case(O.1%).Deceased patients suffered more often from comorbidities,especially heart disease,neurological disorders,hematological disease,cancer,and obesity.None of the deceased patients were admitted for pediatric inflam-matory multisystem syndrome(PIMS).Mortality risk factors were male gender,cardiac comorbidities,cancer,and acute respiratorydistress syndrome.Conclusions SARS-CoV-2 mortality in the French pediatric population was low.Even though the imputability of SARS-Cov-2 on mortality was considered in almost two-thirds of cases,this imputability was considered certain in only one case.展开更多
Background In multisystem inflammatory syndrome in children(MIS-C),diagnostic delay could be associated with severity.This study aims to measure the time to diagnosis in MIS-C,assess its impact on the occurrence of ca...Background In multisystem inflammatory syndrome in children(MIS-C),diagnostic delay could be associated with severity.This study aims to measure the time to diagnosis in MIS-C,assess its impact on the occurrence of cardiogenic shock,and specify its determinants.Methods A single-center prospective cohort observational study was conducted between May 2020 and July 2022 at a tertiary care hospital.Children meeting the World Health Organization MIS-C criteria were included.A long time to diagnosis was defined as six days or more.Data on time to diagnosis were collected by two independent physicians.The primary outcome was the occurrence of cardiogenic shock.Logistic regression and receiver operating characteristic curve analysis were used for outcomes,and a Cox proportional hazards model was used for determinants.Results Totally 60 children were assessed for inclusion,and 31 were finally analyzed[52%males,median age 8.8(5.7-10.7)years].The median time to diagnosis was 5.3(4.2-6.2)days.In univariable analysis,age above the median,time to diagnosis,high C-reactive protein,and high N-terminal pro-B-type natriuretic peptide(NT-proBNP)were associated with cardiogenic shock[odds ratio(OR)6.13(1.02-36.9),2.79(1.15-6.74),2.08(1.05-4.12),and 1.70(1.04-2.78),respectively].In multivariable analysis,time to diagnosis≥6 days was associated with cardiogenic shock[adjusted OR(aOR)21.2(1.98-227)].Time to diagnosis≥6 days had a sensitivity of 89% and a specificity of 77% in predicting cardiogenic shock;the addition of age>8 years and NT-proBNP at diagnosis≥11,254 ng/L increased the specificity to 91%.Independent determinants of short time to diagnosis were age<8.8 years[aHR 0.34(0.13-0.88)],short distance to tertiary care hospital[aHR 0.27(0.08-0.92)],and the late period of the COVID-19 pandemic[aHR 2.48(1.05-5.85)].Conclusions Time to diagnosis≥6 days was independently associated with cardiogenic shock in MIS-C.Early diagnosis and treatment are crucial to avoid the use of inotropes and limit morbidity,especially in older children.展开更多
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.
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.
文摘BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel habits.First-line recommended treatments are limited to combining drugs targeting predominant symptoms,particularly pain(antispasmodics),constipation(laxatives),and diarrhea(loperamide),yielding only a limited therapeutic gain.GASTRAP^(■)DIRECT is a class IIa medical formulation composed of a combination of chitin-glucan and simethicone indicated for the symptomatic treatment of gas-related gastrointestinal disorders by combining different mechanisms of action.AIM To evaluate the efficacy,tolerability,and safety of 4-week GASTRAP^(■)DIRECT treatment in patients with IBS.METHODS In this prospective,multicenter,open-label trial,120 patients with IBS received three sticks of GASTRAP^(■)DIRECT(1.5 g/d of chitin-glucan and 0.75 mg/d of simethicone)per day for 4 weeks.The primary endpoint was the responder rate,defined as the number of patients whose abdominal pain score decreased by≥30%from baseline to week(W)4.The analysis was performed using the per-protocol set.Cardinal symptoms,impact of global symptoms on daily life,change in stool consistency,and improvement in defecatory disorders were evaluated.RESULTS Overall,100 patients were evaluated.At W4,67%(95%CI:57-75)showed improvement in abdominal pain(score:5.8±2.4 vs 2.9±2.0,P<0.0001).Similar improvements were observed for bloating[8.0±1.7 vs 4.7±2.9,P<0.0001;60%(95%CI:50-70)responders],abdominal distension[7.2±2.1 vs 4.4±3.1,P<0.0001;53%(95%CI:43-63)responders],and impact of global symptoms on daily life[7.1±2.0 vs 4.6±2.9,P<0.0001;54%(95%CI:44-64)responders].Stool consistency improved in most patients(90%and 57%for patients with liquid and hard stools,respectively).Overall,42%of patients with defecatory disorders reported very much/considerable improvements by W2.No severe adverse event occurred,and tolerability was rated“good”or“very good”by 93%of patients.CONCLUSION GASTRAP^(■)DIRECT is safe and well tolerated,alleviating IBS symptoms rapidly in 2 weeks.This open-label study suggests that the combination of chitin-glucan and simethicone could be beneficial in patients with IBS.
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.
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.
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>
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.
文摘Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.
文摘The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Bacillus amyloliquefaciens. The efficacy of isolates was tested, at different concentrations. Results showed that one Bacillus isolates (Bc2) and TR were more effective at the lower concentration tested (3 × 105 CFU/ml and 105 conidia/ml).
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Background Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)is responsible for an important mortality rate worldwide.We aimed to evaluate the actual imputability of SARS-CoV-2 on the mortality rate associated with SARS-CoV-2-related illnesses in the pediatric intensive care unit(PICU).Secondary objectives were to identify risk factors for death.Methods This national multicenter comparative study comprised all patients under 18 years old with positive SARS-CoV-2 polymerase chain reactions(PCRs)[acute corona virus disease 2019(COVID-19)or incidental SARS-CoV-2 infection]and/or pediatric inflammatory multisystem syndrome(PIMS)recorded in the French PICU registry(PICURe)between September 1,2021,and August 31,2022.Included patients were classified and compared according to their living status at the end of their PICU stay.Deceased patients were evaluated by four experts in the field of pediatric infectiology and/or pediatric intensive care.The imputability of SARS-CoV-2 as the cause of death was classified into four categories:certain,very probable,possible,or unlikely,and was defined by any of the first three categories.Results There were 948 patients included of which 43 died(4.5%).From this,26 deaths(67%)could be attributed to SARS-CoV-2 infection,with an overall mortality rate of 2.8%.The imputability of death to SARS-CoV-2 was considered certain in only one case(O.1%).Deceased patients suffered more often from comorbidities,especially heart disease,neurological disorders,hematological disease,cancer,and obesity.None of the deceased patients were admitted for pediatric inflam-matory multisystem syndrome(PIMS).Mortality risk factors were male gender,cardiac comorbidities,cancer,and acute respiratorydistress syndrome.Conclusions SARS-CoV-2 mortality in the French pediatric population was low.Even though the imputability of SARS-Cov-2 on mortality was considered in almost two-thirds of cases,this imputability was considered certain in only one case.
文摘Background In multisystem inflammatory syndrome in children(MIS-C),diagnostic delay could be associated with severity.This study aims to measure the time to diagnosis in MIS-C,assess its impact on the occurrence of cardiogenic shock,and specify its determinants.Methods A single-center prospective cohort observational study was conducted between May 2020 and July 2022 at a tertiary care hospital.Children meeting the World Health Organization MIS-C criteria were included.A long time to diagnosis was defined as six days or more.Data on time to diagnosis were collected by two independent physicians.The primary outcome was the occurrence of cardiogenic shock.Logistic regression and receiver operating characteristic curve analysis were used for outcomes,and a Cox proportional hazards model was used for determinants.Results Totally 60 children were assessed for inclusion,and 31 were finally analyzed[52%males,median age 8.8(5.7-10.7)years].The median time to diagnosis was 5.3(4.2-6.2)days.In univariable analysis,age above the median,time to diagnosis,high C-reactive protein,and high N-terminal pro-B-type natriuretic peptide(NT-proBNP)were associated with cardiogenic shock[odds ratio(OR)6.13(1.02-36.9),2.79(1.15-6.74),2.08(1.05-4.12),and 1.70(1.04-2.78),respectively].In multivariable analysis,time to diagnosis≥6 days was associated with cardiogenic shock[adjusted OR(aOR)21.2(1.98-227)].Time to diagnosis≥6 days had a sensitivity of 89% and a specificity of 77% in predicting cardiogenic shock;the addition of age>8 years and NT-proBNP at diagnosis≥11,254 ng/L increased the specificity to 91%.Independent determinants of short time to diagnosis were age<8.8 years[aHR 0.34(0.13-0.88)],short distance to tertiary care hospital[aHR 0.27(0.08-0.92)],and the late period of the COVID-19 pandemic[aHR 2.48(1.05-5.85)].Conclusions Time to diagnosis≥6 days was independently associated with cardiogenic shock in MIS-C.Early diagnosis and treatment are crucial to avoid the use of inotropes and limit morbidity,especially in older children.
