More on core instabilities of magnetic monopoles

In this paper we present new results on the core instability of the 't Hooft Polyakov monopoles we reported on before. This instability, where the spherical core decays in a toroidal one, typically occurs in models in which charge conjugation is gauged. In this paper we also discuss a third conceivable configuration denoted as ``split core'', which brings us to some details of the numerical methods we employed. We argue that a core instability of 't Hooft Polyakov type monopoles is quite a generic feature of models with charged Higgs particles.Comment: Latex, 15 pages, 6 figures; published versio

Climate change and its impact on water consumption in Tunisia: Evidence from ARDL approach

This study aims to explore the link between weather and bottled water consumption in Tunisia using the Autoregressive Distributed Lag model (ARDL) between 1995 and 2020. Ours results show that the precipitation and labor rates in the three sectors have an impact in the short and long term. An increase of 1°C in temperature in the short term leads to an increase in consumption of more than 4 liters of bottled water. However, 1 % more rainfall means a decrease in long-term bottled water consumption of about a quarter of a liter. While in the short term the effect is mixed (both positive and negative). Temperature further increases bottled water consumption in rural areas and among climate-exposed professions

Impact of climate change on yield production in Algeria: evidence from ARDL empirical approach

This study attempts to assess the impact of climate changes factors, such as average rainfall and average temperature on cereal production in Algeria from 1990 to 2019. We employed the autoregressive distributed lag (ARDL) simulations techniques and Granger causality test to estimate the long and short-term effects of climate change variables. The results showed that the rainfall, agricultural technology, agricultural labour, and cultivation of land enhance cereal output. The long-run ARDL model results provides that the temperature does not impact on cereal productivity. The findings provided by Granger causality tests also suggest that there is a unidirectional relationship between cereal production, climatic variables, and non-climate factors. The ARDL technique provides a better methodology to understanding of the variability of cereal production in Algeria as a result of climate factors

Recent advances in drilling hybrid FRP/Ti composite: A state-of-the-art review

Hybrid composite stack, especially FRP/Ti assembly, is considered as an innovative structural configuration for manufacturing the key load-bearing components favoring energy saving in the aerospace industry. Several applications require mechanical drilling for finishing hybrid composite structures. The drilling operation of hybrid FRP/Ti composite, however, represents the most challenging task in modern manufacturing sectors due to the disparate natures of each constituent involved and the complexity to control tool–material interfaces during one single cutting shot. Special issues may arise from the severe subsurface damage, excessive interface consumption, rapid tool wear, etc. In this paper, a rigorous review concerning the state-of-the-art results and advances on drilling solutions of hybrid FRP/Ti composite was presented by referring to the wide comparisons among literature analyses. The multiple aspects of cutting responses and physical phenomena generated when drilling these materials were precisely addressed. A special focus was made on the material removal modes and tool wear mechanisms dominating the bi-material interface consumption (BIC) with respect of investigating strategies used. The key conclusions from the literature review were drawn to point out the potential solutions and limitations to be necessarily overcome for reaching both (i) enhanced control of drilling operation, and (ii) better finish quality of FRP/Ti part

Anti-inflammatory drug diclofenac removal by a synthesized MgAl layered double hydroxide

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGLayered double hydroxides (LDHs) containing Mg:Al (molar ratio 3:1) were synthesized by coprecipitation from nitrate salts under alkaline conditions. Their further characterisation by different techniques allowed the determination of their structural, nanotextural and chemical properties. XRD measurements confirmed the high crystallisation with the presence of two metal cations (Mg2+ and Al3+). The use of these materials as eco-friendly adsorbents was analysed to remove diclofenac from wastewater. Under optimal conditions (0.4 g L 1, 30 ppm initial pollutant concentration, pH 8.5), around 65% diclofenac removal was achieved after 60 min of treatment. The pseudo-second kinetic order model and Freundlich isotherm accurately described the experimental data, suggesting chemisorption process on the heterogeneous LDH surface. After diclofenac adsorption, XRD analysis revealed an increase in interlayer spacing followed by contraction of adjacent layers, so that anion exchange between layer was considered to be the main mechanism for diclofenac adsorption. Thermodynamic studies indicate diclofenac adsorption occurs spontaneously, endothermically, and also, with increasing randomness at the solid/solution surface. Batch test revealed limitations in terms of long-term stability of the material. Therefore, a post-synthesis strategy, calcination, was required to increase the degree of resistance. For this purpose, the effect of calcination temperature was examined in the range 200–300 C. Although, the kinetic rate constant decreased slightly after calcination, the improvement of its structural properties allowed to operate under continuous system.Ministerio de Ciencia e Innovación | Ref. PID2020- 113667 GB-I00Ministerio de Ciencia e Innovación | Ref. PDC2021-121394-I00Xunta de Galicia | Ref. ED431C 2021-43Xunta de Galicia | Ref. ED481B 2018/09

FORMATION DES TAUX DES OBLIGATIONS SOUVERAINES A LONG TERME : ANALYSE DES EFFETS DES DECISIONS DE LA BANQUE CENTRALE

Ce travail a pour objectif d’examiner la relation de causalité entre la politique monétaire menée par BAM et les différents segments de la courbe des taux d’intérêt. Pour ce faire, nous avons eu recours aux tests de causalité au sens de Granger et nous avons retenu les variables suivantes : le Taux Moyen Pondéré des opérations, au jour le jour, du prêt et d’emprunt de liquidités sur le marché interbancaire marocain (TMPjj) pour représenter les décisions de BAM en matière de politique monétaire ; les taux des Bons du Trésor à 13 semaines, 26 semaines, 52 semaines (taux courts), 2 ans, 5 ans (taux moyens), 10 ans, 15 ans et 20 ans (taux longs).Les résultats économétriques ont montré qu’il existe un lien de causalité unidirectionnel allant de la politique monétaire (TMPjj) aux taux d’intérêt des BDT à très court terme (Taux d’intérêt des BDT à 13 semaines). Par conséquent, les mesures prises par l’institut d’émission, toutes choses étant égales par ailleurs, en maniant ses taux directeurs peuvent influencer l’évolution de la partie très courte de la structure par terme des taux d’intérêt au Maroc. Les résultats ont révélé aussi que, au sens de Granger, il n’y a aucun lien de causalité (unidirectionnel et bidirectionnelle) entre la politique monétaire et les autres taux d’intérêt des BDT (T.26.S, T.52.S, T.2 ans, T.5 ans, T.10 ans, T.15 ans et T.20 ans). En effet, les variations des taux d’intérêt des BDT au-delà de 13 semaines ne sont pas sensibles aux modifications du taux du marché monétaire interbancaire et par ricochet aux actions des autorités monétaires. Ces résultats nous permettront donc de déduire que BAM n’arrive pas à impacter les taux de rendement des obligations souveraines à long terme.En somme, il ressort de nos résultats empiriques que les taux obligataires à très court terme sont sensibles aux annonces de la banque centrale notamment aux modifications de ses taux directeurs. Cette réaction est le signe d’une capacité prédictive considérable des décisions de BAM

Landau-De Gennes theory of nematic liquid\ud crystals: the Oseen-Frank limit and beyond

We study global minimizers of a continuum Landau-De Gennes energy functional for nematic liquid crystals, in three-dimensional domains, subject to uniaxial boundary conditions. We analyze the physically relevant limit of small elastic constant and show that global minimizers converge strongly, in W 1,2 , to a global minimizer predicted by the Oseen-Frank theory for uniaxial nematic liquid crystals with constant order parameter. Moreover, the convergence is uniform in the interior of the domain, away from the singularities of the limiting Oseen-Frank global minimizer. We obtain results on the rate of convergence of the eigenvalues and the regularity of the eigenvectors of the Landau-De Gennes global minimizer.\ud \ud \ud We also study the interplay between biaxiality and uniaxiality in Landau-De Gennes global energy minimizers and obtain estimates for various related quantities such as the biaxiality parameter and the size of admissible strongly biaxial regions

High levels of gut-homing immunoglobulin A+ B lymphocytes support the pathogenic role of intestinal mucosal hyperresponsiveness in immunoglobulin A nephropathy patients

No abstract availabl