Search results for " Phase"
showing 10 items of 1862 documents
Effects of resveratrol on the ultrastructure of Botrytis cinerea conidia and biological significance in plant/pathogen interactions
2012
International audience; Many roles have been ascribed to stilbenes, namely as antimicrobial, deterrent or repellent compounds in plants, protecting them from attacks by fungi, bacteria, nematodes or herbivores, acting both as constitutive and active defense (phytoalexin) compounds. More recently, stilbenes (especially resveratrol and its derivatives) were acclaimed for their wondrous effects and wide range of purported healing and preventive powers as cardioprotective, antitumor, neuroprotective and antioxidant agents. Although there is a huge number of works concerning the role of resveratrol in human health, reports on the antifungal activity of this compound are still scarce. This study …
The Spatial Dimension in Population Fluctuations
1997
Theoretical research into the dynamics of coupled populations has suggested a rich ensemble of spatial structures that are created and maintained either by external disturbances or self-reinforcing interactions among the populations. Long-term data of the Canadian lynx from eight Canadian provinces display large-scale spatial synchrony in population fluctuations. The synchronous dynamics are not time-invariant, however, as pairs of populations that are initially in step may drift out of phase and back into phase. These observations are in agreement with predictions of a spatially-linked population model and support contemporary population ecology theory.
Anhydrobiosis: Inside yeast cells
2018
International audience; Under natural conditions yeast cells as well as other microorganisms are regularly subjected to the influence of severe drought, which leads to their serious dehydration. The dry seasons are then changed by rains and there is a restoration of normal water potential inside the cells. To survive such seasonal changes a lot of vegetative microbial cells, which belong to various genera and species, may be able to enter into a state of anhydrobiosis, in which their metabolism is temporarily and reversibly suspended or delayed. This evolutionarily developed adaptation to extreme conditions of the environment is widely used for practical goals - for conservation of microorg…
Experimental size-selective harvesting affects behavioral types of a social fish
2019
In most fisheries, larger fish experience substantially higher mortality than smaller fish. Body length, life history, and behavioral traits are often correlated, such that fisheries-induced changes in size or life history can also alter behavioral traits. However, empirical evidence regarding how size-selective harvesting alters the evolution of behavioral traits in exploited stocks is scarce. We used experimental lines of Zebrafish Danio rerio that were exposed to positively size-selective, negatively size-selective, or random harvest over five generations. Our aim was to investigate whether simulated fishing changed the mean personality of the surviving females five generations after ini…
Liquid Crystal Phases in Suspensions of Charged Plate-Like Particles
2012
International audience; Anisotropic interactions in colloidal suspensions have recently emerged as a route for the design of new soft materials. Nonisotropic particles can form nematic, smectic, hexatic, and columnar liquid crystals. Although the formation of these phases is well rationalized when excluded volume is solely at play, the role of electrostatic interactions still remains unclear and even less so when particles present a charge heterogeneity, for example, clays. Here, we use Monte Carlo simulations of concentrated suspensions of charged disk-like particles to reveal the role of Coulomb interactions and charge anisotropy underlying liquid crystal formation and structures. We obse…
Ultrasonic phased array inspection of a Wire + Arc Additive Manufactured (WAAM) sample with intentionally embedded defects
2019
In this study, Wire + Arc Additive Manufacture (WAAM) was employed to manufacture a steel specimen with intentionally embedded defects which were subsequently used for calibration of an ultrasonic phased array system and defect sizing. An ABB robot was combined with the Cold Metal Transfer (CMT) Gas Metal Arc (GMA) process to deposit 20 layers of mild steel. Tungsten-carbide balls (ø1-3 mm) were intentionally embedded inside the additive structure after the 4th, 8th, 12th and 18th layers to serve as ultrasonic reflectors, simulating defects within the WAAM sample. An ultrasonic phased array system, consisting of a 5 MHz 64 Element phased array transducer, was used to inspect the WAAM sample…
Robotic geometric and volumetric inspection of high value and large scale aircraft wings
2019
Increased demands in performance and production rates require a radical new approach to the design and manufacturing of aircraft wings. Performance of modern robotic manipulators has enabled research and development of fast automated non-destructive testing (NDT) systems for complex geometries. This paper presents recent outcomes of work aimed at removing the bottleneck due to data acquisition rates, to fully exploit the scanning speed of modern 6-DoF manipulators. The geometric assessment of the parts is carried out with a robotised dynamic laser scanner encoded through an absolute laser tracker. This method allows scanning speeds up to 330mm/s at 1mm pitch. State of the art ultrasonic ins…
The role of extracellular polymeric substances (EPS) on aerobic granules formation: comparison between a case of synthetic wastewater supply and anot…
2017
The paper focused on the evolution and the comparison of the extracellular polymeric substances (EPSs) content during the granulation process in two Granular Sequencing Batch Airlift Reactors (GSBAR) (3,5 L) fed with synthetic (R1) and industrial wastewater (R2). The results showed that in both the reactors the EPSs, in particular proteins (PN), were mainly produced during the feast phase because of the high substrate availability, especially under conditions of metabolic stress. Then, the EPSs content reduced during the famine period, because of biodegradation by bacteria. More in detail, during the granulation process, a greater polysaccharides (PS) consumption occurred in both reactors, …
Retinoic Acid affects Lung Adenocarcinoma growth by inducing differentiation via GATA6 activation and EGFR and Wnt inhibition
2016
AbstractA fundamental task in cancer research aims at the identification of new pharmacological therapies that can affect tumor growth. Differentiation therapy might exploit this function not only for hematological diseases, such as acute promyelocytic leukemia (APML) but also for epithelial tumors, including lung cancer. Here we show that Retinoic Acid (RA) arrests in vitro and in vivo the growth of Tyrosine Kinase Inhibitors (TKI) resistant Non Small Cell Lung Cancer (NSCLC). In particular, we found that RA induces G0/G1 cell cycle arrest in TKI resistant NSCLC cells and activates terminal differentiation programs by modulating the expression of GATA6, a key transcription factor involved …
Medroxyprogesterone acetate is a useful alternative to a gonadotropin-releasing hormone antagonist in oocyte donation: a randomized, controlled trial.
2021
Objective To compare ovarian response and reproductive outcomes in oocyte donors undergoing pituitary suppression with medroxyprogesterone acetate (MPA) versus those undergoing conventional treatment with a gonadotropin-releasing hormone (GnRH) antagonist. Design A prospective, randomized, controlled trial of cycles was conducted from October 2017 to June 2019 to evaluate ovarian response in terms of the number of oocytes. The reproductive outcomes of the recipients were retrospectively analyzed later. Setting A university-affiliated private in vitro fertilization center. Patient(s) We randomly divided 318 donors into 2 groups in a 1:1 ratio. The oocytes obtained were assigned to 364 recipi…