On the minimization problem of sub-linear convex functionals

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Hydrothermal synthesis of (C5H14N2)[CoCl4]⸳0.5H2O: Crystal structure, spectroscopic characterization, thermal behavior, magnetic properties and biological evaluation

The organic-inorganic compound (C5H14N2)[CoCl4]⸳0.5H2O, I, was characterized by various physicochemical techniques. The X-ray diffraction analysis revealed that the compound crystallizes in the centrosymmetric space group C2/c of the monoclinic system. The atomic arrangement the Co(II) complex is built from isolated [CoCl4]2– anions, 1-methylpiperazine-1,4-diium [C5H14N2]2+ cations and free water molecules. The crystal structure study showed that the cohesion of I is assured through N–H···Cl and N–H···O hydrogen bonds giving birth to a 3-D architecture. Hirshfeld surface analysis revealed that Cl···H/H···Cl and H···H (58.5 and 36.4%, respectively) are the most significant interactions between species. Minor O···H/H···O interactions are also present. The compound was characterized by thermal analysis, TGA-DTA showed the removal of the co-crystallized water before 100 °C and a first mass loss at around 120 °C. Magnetic measurements are in good agreement with isolated, S = 3/2, tetrahedral [CoCl4]2− anions. The negative Weiss constant of -1.35 indicates single-ion anisotropy and very weak antiferromagnetic interactions. UV–visible spectroscopy reveals three weak absorption bands in the visible range due to the d-d electronic transitions typical of the Co(II) tetra-coordinated. A bioassay showed antibacterial activity against the gram negative Klebsiella pneumonia and gram positive Bacillus ceureus, Listeria monocytogenes, and Micrococcus lutues

Architectural framework of digital marketing: Examining its relationship with customers and the intermediary role of electronic quality in Saudi commercial banks

This study on the moderating effect of electronic quality in mobile marketing aims to examine the factors that influence how Saudi commercial banks are viewed by their customers. A research framework that sheds light on the state of the research was developed after a comprehensive analysis of the accessible literature. The theoretical foundation of this study is the idea of perceived characteristics, which identifies five critical factors that influence adoption rates. The empirical results of this study are presented based on a sample of 300 respondents (n = 300). The research was conducted using the statistical technique of least squares structural equation modeling (PLS-SEM). The reporting format conforms to accepted PLS-SEM analysis standards. The results reveal a significant association between mobile marketing and customer perceptions in the context of Saudi commercial banks, especially when electronic quality is used as a mediating variable. Based on these findings, we suggest that Saudi commercial banks should strategically include e-quality in their digital marketing campaigns, paying special attention to mobile marketing

Second order averaging for the nonlinear Schroedinger equation with strongly anisotropic potential

International audienceWe consider the three dimensional Gross-Pitaevskii equation (GPE) describing a Bose-Einstein Condensate (BEC) which is highly confi ned in vertical z direction. The highly confi ned potential induces high oscillations in time. If the confi nement in the z direction is a harmonic trap (which is widely used in physical experiments), the very special structure of the spectrum of the confi nement operator will imply that the oscillations are periodic in time. Based on this observation, it can be proved that the GPE can be averaged out with an error of order of epsilon, which is the typical period of the oscillations. In this article, we construct a more accurate averaged model, which approximates the GPE up to errors of order epsilon squared. Then, expansions of this model over the eigenfunctions (modes) of the vertical Hamiltonian Hz are given in convenience of numerical application. Effi cient numerical methods are constructed for solving the GPE with cylindrical symmetry in 3D and the approximation model with radial symmetry in 2D, and numerical results are presented for various kinds of initial data

Fit between humanitarian professionals and project requirements: hybrid group decision procedure to reduce uncertainty in decision-making

Choosing the right professional that has to meet indeterminate requirements is a critical aspect in humanitarian development and implementation projects. This paper proposes a hybrid evaluation methodology for some non-governmental organizations enabling them to select the most competent expert who can properly and adequately develop and implement humanitarian projects. This methodology accommodates various stakeholders’ perspectives in satisfying the unique requirements of humanitarian projects that are capable of handling a range of uncertain issues from both stakeholders and project requirements. The criteria weights are calculated using a two-step multi-criteria decision-making method: (1) Fuzzy Analytical Hierarchy Process for the evaluation of the decision maker weights coupled with (2) Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to rank the alternatives which provide the ability to take into account both quantitative and qualitative evaluations. Sensitivity analysis have been developed and discussed by means of a real case of expert selection problem for a non-profit organisation. The results show that the approach allows a decrease in the uncertainty associated with decision-making, which proves that the approach provides robust solutions in terms of sensitivity analysis

ForCenS-LGM: a dataset of planktonic foraminifera species assemblage composition for the Last Glacial Maximum

Species assemblage composition of marine microfossils offers the possibility to investigate ecological and climatological change on time scales inaccessible using conventional observations. Planktonic foraminifera - calcareous zooplankton - have an excellent fossil record and are used extensively in palaeoecology and palaeoceanography. During the Last Glacial Maximum (LGM; 19,000 – 23,000 years ago), the climate was in a radically different state. This period is therefore a key target to investigate climate and biodiversity under different conditions than today. Studying LGM climate and ecosystems indeed has a long history, yet the most recent global synthesis of planktonic foraminifera assemblage composition is now nearly two decades old. Here we present the ForCenS-LGM dataset with 2,365 species assemblage samples collected using standardised methods and with harmonised taxonomy. The data originate from marine sediments from 664 sites and present a more than 50% increase in coverage compared to previous work. The taxonomy is compatible with the most recent global core top dataset, enabling direct investigation of temporal changes in foraminifera biogeography and facilitating seawater temperature reconstructions

Perspectives on Preparedness for Chemical, Biological, Radiological, and Nuclear Threats in the Middle East and North Africa Region: Application of Artificial Intelligence Techniques

Over the past 3 decades, the diversity of ethnic, religious, and political backgrounds worldwide, particularly in countries of the Middle East and North Africa (MENA), has led to an increase in the number of intercountry conflicts and terrorist attacks, sometimes involving chemical and biological agents. This warrants moving toward a collaborative approach to strengthening preparedness in the region. In disaster medicine, artificial intelligence techniques have been increasingly utilized to allow a thorough analysis by revealing unseen patterns. In this study, the authors used text mining and machine learning techniques to analyze open-ended feedback from multidisciplinary experts in disaster medicine regarding the MENA region's preparedness for chemical, biological, radiological, and nuclear (CBRN) risks. Open-ended feedback from 29 international experts in disaster medicine, selected based on their organizational roles and contributions to the academic field, was collected using a modified interview method between October and December 2022. Machine learning clustering algorithms, natural language processing, and sentiment analysis were used to analyze the data gathered using R language accessed through the RStudio environment. Findings revealed negative and fearful sentiments about a lack of accessibility to preparedness information, as well as positive sentiments toward CBRN preparedness concepts raised by the modified interview method. The artificial intelligence analysis techniques revealed a common consensus among experts about the importance of having accessible and effective plans and improved health sector preparedness in MENA, especially for potential chemical and biological incidents. Findings from this study can inform policymakers in the region to converge their efforts to build collaborative initiatives to strengthen CBRN preparedness capabilities in the healthcare sector

Electrochemistry and microbial ecology evaluation of anodic biofilms for improved microbial fuel cells scale-up

International audienc

Microbial ecology approach of anodic biofilms for the study of scaled-up microbial fuel cells

International audienceSince 1911 when Potter described bacteria that could produce electrical currents interest in this ability and associatedtechnologies like microbial fuel cells (MFCs) has grown especially the last 20 years. Many MFCs have an anaerobic chamberfilled with the feeding solution where are immerged an anode and a cathode which is generally in contact with air for oxygensupply. After inoculation with bacteria (pure bacterial culture or from environmental sources such as wastewater), biofilmsdevelop on the anode and cathode. Some bacterial strains are able to use the anode as their terminal electron acceptor.These electrons travel via an external electric circuit to the cathode where the oxygen reduction occurs with or withoutbacterial participation.The application of MFCs for the production of energy from wastewater requires the scale-up of such devices which, for now,doesn’t allow electrical yield comparable to lab-scale MFCs. Our work was based on the hypothesis that typical scale-upefforts modify specific MFC parameters (substrate diffusion, geometry, hydraulic forces… ) which in turn affect the anodicbiofilm (microorganism selection, physical structure of the biofilm, electrons transport strategies… ) and that is one majorreason for electric yield variations. We investigated microbial ecology and electricity production of three MFCs of differentvolumes: 10 mL, 500 mL, 4 L operated under similar conditions and identical MFC parameters.Electrical production and microbial community structure (16S rRNA gene sequencing to evaluate the enrichment ofelectroactive bacteria species like Geobacter sulfurreducens or Shewanella oneidensis MR-1) and function (to examine foodweb and electron exchange functions) were monitored during the MFC start-up and operation. In parallel, the physicalstructure of the biofilms (such as density, thickness, bacterial distribution and nanowire (conductive pili) presence) wasstudied by microscopy techniques and proteomics analysis

Electrochemistry and microbial ecology approach of anodic biofilms for the study of scaled-up microbial fuel cells

International audienceSince 1911 when Potter described bacteria that could produce electrical currents, interest in this ability and associated technologies like microbial fuel cells (MFCs) has grown specially in the last 20 years. Many MFCs have an anaerobic chamber filled with the feeding solution where an anode and a cathode are immerged although the cathode can be in contact with air for the supply of oxygen. Biofilms develop on the anode and cathode after inoculation with bacteria (pure bacterial culture or from environmental sources such as wastewater). Some bacterial strains (e.g., Geobacter species) are able to use the anode as their terminal electron acceptor. In the anodic biofilm, the stepwise and complex electron pathway from bacteria to the anode results in charge transfer resistance that can induce potential energy losses. The electrons travel via an external electric circuit to the cathode where the oxygen reduction occurs with or without bacterial participation.The application of MFCs for the production of energy from wastewater requires the scale-up that does not yet produce an electrical yield comparable to lab-scale MFCs. Our work was based on the hypothesis that typical scale-up efforts modify specific MFC parameters (substrate diffusion, geometry, hydraulic forces, etc.) that in turn affect the anodic biofilm and the efficiency of electron transfer to the anode. We investigated the microbial ecology and electricity production of three MFCs of different volumes: 10 mL, 500 mL, 4 L operated under similar conditions and identical MFC parameters. Electrical production, electrochemical characterization and microbial community structure (16S rRNA gene sequencing to evaluate the enrichment of electroactive bacteria species like Geobacter sulfurreducens and Shewanella oneidensis MR-1) and function (to examine electron exchange functions) were monitored during the MFC start-up and operation. In parallel, the physical structure of the biofilms (such as density, thickness, bacterial distribution and nanowire (conductive pili) presence) was studied by microscopy techniques and proteomics analysis.In addition, we electrochemically characterized several MFCs with different architectures and electrode material by electrochemical impedance spectroscopy and voltammetry techniques. The aim was to model electrical behaviour and equivalent circuit of MFCs as batteries in relation with the identification of redox proteins involved in electron transfer in order to understand the limiting step of extracellular electron transfer to electrodes in anodic biofilms