Nonlinear wavelength selection in surface faceting under electromigration

We report on the control of the faceting of crystal surfaces by means of surface electromigration. When electromigration reinforces the faceting instability, we find perpetual coarsening with a wavelength increasing as $t^{1/2}$. For strongly stabilizing electromigration, the surface is stable. For weakly stabilizing electromigration, a cellular pattern is obtained, with a nonlinearly selected wavelength. The selection mechanism is not caused by an instability of steady-states, as suggested by previous works in the literature. Instead, the dynamics is found to exhibit coarsening {\it before} reaching a continuous family of stable non-equilibrium steady-states.Comment: 5 pages, 4 figures, submitte

Suivi automatique de variations modales à l’aide du technique de décrément aléatoire sans filtrage application à des enregistrements de vibrations ambiantes des bâtiments

This thesis proposes a novel approach to automatically monitor the variationsof the frequencies and the damping ratios of actual high-rise buildings subjected to realworldambient vibrations. The approach aims at dealing simultaneously with the followingchallenges: multi-component signals recorded over the aforementioned buildings and havingclosely-spaced frequency modes with low, exponential and damped amplitudes of theirimpulse responses and contaminated with high additive noises. The approach relies on theapplication of the Random Decrement Technique directly over the multi-component signalunder study which leads to the extraction of a Multi-mode Random Decrement Signatureequivalent to the system impulse response. To characterize such a signature, we propose asignal model based on the physical structure of the building from where the modal parameterscan be estimated. For the purpose of non-biased modal estimate, we propose to usean iterative method based on a Maximum-Likelihood Estimation optimized by a simulatedannealing technique. In order to initialize the parameters of the latter, a first step is designedwhich can be considered as an independent estimator of the modal parameters. Theoriginality of this step lies in its ability to automatically define the number of modes of theestimated signature through the use of the statistical properties of a Welch spectrum. Themodal parameters estimated by the spectral-based initialization step are finally refined bythe Maximum-Likelihood Estimation step. The latter reduces the bias in the estimation andyields more reliable and robust results. All these steps are defined in order to be able to automaticallymonitor the health of a building via a long-term real-time tracking of the modalvariations over time without the need to any user intervention . In addition, the proposedapproach has paid very special attention to the automatic estimation of the most problematicmodal parameter, i.e., the damping ratio. Such features making two of the original featuresas compared to existing techniques. The adaptability and functionality of AMBA is validatedover six actual buildings excited by real-world ambient vibrations. From the obtained results,AMBA proved high efficiency in automatically estimating the frequencies and moreover thedamping ratios in case of closely-spaced frequency modes and very low signal-to-noise ratiolevel. AMBA as well demonstrated a good performance for tracking the modal variationsover time.Cette thèse propose une nouvelle approche pour surveiller automatiquementles variations des fréquences et des taux d’amortissement des batiments de grande hauteursoumis à des vibrations ambiantes. L’approche vise à relever simultanément avec les défissuivants: signaux multi-composants enregistrées sur les bâtiments mentionnés ci-dessusavec des réponses impulsionnelles ayant des modes de fréquences rapprochées, des amplitudesfaibles, exponentielles et amorties noyées dans des bruits additifs élevés. La méthoderepose sur l’application de la technique de décrément aléatoire directement sur le signal multicomposantece qui conduit à l’estimation d’une signature de décrément aléatoire multi-modeéquivalente à la réponse impulsionnelle de système. Pour caractériser une telle signature,nous proposons un modèle de signal basé sur la structure physique du bâtiment à partir delaquelle les paramètres modaux peuvent être estimés. Dans le but d’avoir une estimationnon biaisée, nous proposons d’utiliser une méthode itérative sur la base d’une estimation dumaximum de vraisemblance optimisé par une technique de recuit simulé. Afin d’initialiserles paramètres de ce dernier, une première étape est conçu qui peut être considéré commeun estimateur indépendant des paramètres modaux. L’originalité de cette étape réside danssa capacité à définir automatiquement le nombre de modes de la signature estimé grâce àl’utilisation des propriétés statistiques d’un spectre estimé par une transformée de Fourier.Les paramètres modaux estimés par l’étape d’initialisation sont finalement affinés par l’étaped’estimation du maximum de vraisemblance. Celui-ci réduit le biais de l’estimation et donnedes résultats plus fiables et plus robustes. Toutes ces étapes sont définies de manière à être enmesure de surveiller automatiquement l’état de santé d’un bâtiment par l’intermédiaire d’unsuivi long terme en temps réel des variations modales dans le temps sans que l’interventionde l’utilisateur soit nécessaire. En outre, l’approche proposée a accordé une attention touteparticulière à l’estimation automatique du paramètre modal les plus problématique, c’està-dire, le taux d’amortissement. Ces deux caractéristiques sont des atouts originaux parrapport aux techniques existantes. L’adaptabilité et la fonctionnalité de l’AMBA a été validésur six bâtiments réels excités par des vibrations ambiantes. D’après les résultats obtenus,AMBA a prouvé une grande efficacité dans l’estimation automatique des fréquences et destaux d’amortissement dans le cas de modes de fréquences rapprochées et avec un très faiblerapport signal-sur-bruit. AMBA a ainsi démontré une bonne performance pour suivre lesvariations modales au fil du temps

Untargeted metabolomics to evaluate antifungal mechanism: a study of Cophinforma mamane and Candida albicans interaction

Microbial interactions between filamentous fungi and yeast are still not fully understood. To evaluate a potential antifungal activity of a filamentous fungus while highlighting metabolomic changes, co-cultures between an endophytic strain of Cophinforma mamane (CM) and Candida albicans (CA) were performed. The liquid cultures were incubated under static conditions and metabolite alterations during the course were investigated by ultra-performance liquid chromatography–tandem mass spectrophotometry (UPLC–MS/MS). Results were analyzed using MS-DIAL, MS-FINDER, METLIN, Xcalibur, SciFinder, and MetaboAnalyst metabolomics platforms. The metabolites associated with catabolic processes, including the metabolism of branched-chain amino acids, carnitine, and phospholipids were upregulated both in the mono and co-cultures, indicating fungal adaptability to environmental stress. Several metabolites, including C20 sphinganine 1-phosphate, myo-inositol, farnesol, gamma-undecalactone, folinic acid, palmitoleic acid, and MG (12:/0:0/0:0) were not produced by CA during co-culture with CM, demonstrating the antifungal mechanism of CM. Our results highlight the crucial roles of metabolomics studies to provide essential information regarding the antifungal mechanism of C. mamane against C. albicans, especially when the lost/undetected metabolites are involved in fungal survival and pathogenicity

Mapping geosites as gateways to the geotourism management in Central High-Atlas (Morocco)

Demnate commune and High-Tessaout valley are located in the Moroccan central High-Atlas. They have a great and much diversified geological and geomorphological heritage and exceptional landscapes of high mountains. The data obtained from the current work indicate that the studied area present high tourist vocation, in the fact that this territory preserves a large number of geosites linked to many witnesses fossils of extinct animals such dinosaurs footprints, outcropping rock formations of the Precambrian and Mesozoic. Further, it has many remarkable landforms and geosites such as canyons, natural bridge, spectacular waterfalls and scree slopes. The findings support that the area attracts many tourists every year. However, this number remains restricted due to the lack of tools of promotion and mediation of its geoheritage and also due to the low exploitation of the geodiversity. Regarding this situation, geotouristic routes represented on touristic map appear as an essential tool for geotourism promotion and as an efficient means of geosciences popularisation. This paper illustrates three geotouristic routes describing the main geosites in rural areas of Demnate and High-Tessaout valley. These geotourism itineraries can help to explain the high potential interest of the studied areas in geotourism terms

Genetic study of sex inversion in humans

Sex reversal is considered to be a form of disorders of sex development or DSD (disorders/Differences of sex development). This is an inconsistency between gonadal, phenotypic and chromosomal sex. Sexual development, including the development of gonads and organs reproduction and the acquisition of secondary sexual characteristics, is under genetic control. Indeed, following the bibliographic study carried out in this report, we were able to better understand the pathophysiology of sex reversal, enumerate the associated genetic mutations and identify the signaling pathways affected. In addition, a retrospective study was performed to determine the frequency of sex reversal compared to other categories of DSD. This work focused on a sample of 981 patients with clinical signs indicating the presence of DSD. These patients presented to the Cytogenetics laboratory of the Institut Pasteur in Morocco between the years 2011 and 2021. The karyotype was performed on a heparinized tube according to the standard method. Based on the karyotype results, we found 74 cases of sex inversion corresponding to 7.54%. Abnormal karyotypes accounted for 37.31% with a predominance of Turner syndrome (41.53%), 26.23% of Klinefelter syndrome, 12.3% of patients presented with XY female type sex inversion, 7.92% with sex reversal type XX men and 7.65% had mixed gonadal dysgenesis. Finally, to guide the diagnosis, we established a course of action indicating the genes which are the most incriminated in the two types of sex inversion

Diethylenetriamine/diamines/copper (II) complexes [Cu(dien)(NN)]Br2: Synthesis, solvatochromism, thermal, electrochemistry, single crystal, Hirshfeld surface analysis and antibacterial activity

Two dicationic water soluble mixed triamine/diamine copper (II) complexes, of general formula [Cu(dien)NN]Br2(1–2) [dien = diethelenetriamine and NN is en = ethylenediamine or Me4en = N,N′,N,N′-tetramethylethylenediamine] were prepared under ultrasonic mode with a relatively high yield. These complexes were characterized by elemental microanalysis, UV visible IR spectroscopy, and thermal and electrochemical techniques. In addition, complex 2 structure was solved by X-ray single crystal and Hirshfeld surface analysis. The complex exhibits a distorted square pyramidal coordination environment around Cu(II) centre. The solvatochromism of the desired complexes was investigated in water and other suitable organic solvents. The results show that the Guttmann’s DN parameter values of the solvents have mainly contributed to the shift of the d–d absorption band towards the linear increase in the wavelength of the absorption maxima of the complexes. The complex 1 showed higher antibacterial activity against the studied microorganisms compared to complex 2. Both complexes revealed promising antibacterial activities.The authors would like to extend their sincere appreciation to the Deanship of Scientific Research at King Saud University for its funding of this Research group NO (RG-0257-1435-1436)

Sol-Gel to Prepare Nickel Doped TiO2 Nanoparticles for Photocatalytic Treatment of E 131 VF Food Dye Wastewater

Sol–gel method was applied for synthesis of TiO2 nanoparticles in the existence of different volumes of ethanol (10–50 mL) with the purpose to find optimized synthesis conditions. Also, nickel doped TiO2 nanoparticles (Ni/TiO2 molar ratio: 0.1-1.0%) were prepared by the similar technique but in the existence of 10 mL ethanol and heated at different temperatures (300 °C –600 °C). XRD, SEM/EDX, UV-Vis DRS, FTIR and Raman spectroscopy were applied to identify the structural and morphological characteristics of the as-synthesized samples. XR diffraction results verified that TiO2 samples prepared with various volumes of ethanol (10–50 mL) consist of anatase and brookite phases up to 500 °C and rutile phase at 600 °C. The intensity of brookite diffraction decreased with the increase of calcination temperatures. Also, the low ethanol volume favored for formation of rutile phase at 600 °C. The addition of Ni(II) during the preparation of TiO2 nanoparticles prevented the formation of rutile phase. The undoped samples were synthesized with 10 and 20 mL ethanol and treated at 500 °C displayed the best catalytic performance for photocatalytic treatment of E 131 VF dye solution (rate constant: 0.051 and 0.061 (a.u) respectively). Ni doped TiO2 samples displayed lower photoactivity and rate constant

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat