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In this paper we present a report about the birds of the southern part of the Algerian Sahara. A total of 62 species were recorded with direct observations in nine different localities of two regions (from Tamanrasset city to In Guezzam city), belonging to 29 families and 12 orders in 2021. Three species were recorded for the first time in Algeria, White-throated Bee-eater (Merops albicollis), Cut-throat Finch (Amadina fasciata) and Village Indigobird (Vidua chalybeata). The latter two were probably escaped from captivity. The House Sparrow (Passer domesticus) were observed for the first time in this region.

Due to phenotypic plasticity and sex-biased selective pressures, intraspecific variation in tortoise morphology is usually assessed by studying sexual dimorphism. However, inferences may differ based on the choice of shell size measurements for analyses. In this work, we identified linear measurements that best describe sexual dimorphism for the spur-thighed tortoise Testudo graeca whitei. We assessed 34 carapace and plastron measurements in 67 individuals (24 males, 43 females) in a population at the natural Mergueb site located on the central limit of the Algerian steppe. Twenty-two out of 34 measurements significantly showed sexual size dimorphism in ANOVA tests. When analyzing sexual shape dimorphism with ANCOVAs, nine measurements showed no shared allometry with the measurements used as covariates to correct by size. Meanwhile, 17 out of the remaining 23 measurements showed significant differences in shape. PCA analyses similarly described T. graeca’s sexual dimorphism. In general, females tend to be bigger than males, especially in central scutes what is probably linked with clutch sizes commitments. On the other hand, males are larger-sized in anterior and posterior scutes, probably as a result of courtship, male fighting and copulation. Some of the analyzed measurements are revealed as being especially adequate for further studying the geographical variation of sexual dimorphism in Testudo graeca

Entanglement, and quantum correlation, are precious resources for quantum technologies implementation based on quantum information science, such as quantum communication, quantum computing, and quantum interferometry. Nevertheless, to our best knowledge, a directly or numerically computable measure for the entanglement of multipartite mixed states is still lacking. In this work, ${\it i)}$ we derive a measure of the degree of quantum correlation for mixed multipartite states. The latter possesses a closed-form expression valid in the general case unlike, to our best knowledge, all other known measures of quantum correlation. ${\it ii)}$ We further propose an entanglement measure, derived from this quantum correlation measure using a novel regularization procedure for the density matrix. Therefore, a comparison of the proposed measures, of quantum correlation and entanglement, allows one to distinguish between quantum correlation detached from entanglement and the one induced by entanglement and, hence, to identify separable but non-classical states. Finally, we have tested our entanglement measure, on states well-known in literature: a general Bell diagonal state and the Werner states, which are easily tractable with our regularization procedure, and we have verified the accordance between our measures and the expected results for these states.

The choice of the structure of the mathematical model of thermal-hydraulic processes in the oil cavities of the GTE rotor supports has beensubstantiated. A three-dimensional CFD model has been built to calculate multiphase currents involving information on the flow distribution and heat exchange given in the scientific literature. We have considered the approaches and individual models used for these purposes. The resulting solutions are consistent with the results of the experiment on a model support and generally accepted ideas about the processes in a given class of devices. The distribution of oil in the chamber, the phase current lines, the temperature and velocity fields have been given, as well as the velocity vectors for various CFD models (VOF, Euler, Inhomogeneous) and solver types (steady and non-steady). Based on the analysis of the results obtained, it has been found that the Euler model involving a non-steady solver yields the smallest difference with the experimental values for a heat transfer coefficient. In all cases, when gravity is considered, there is an asymmetrical distribution of the oil film. The result is a change in the thermal resistance of the boundary layer and, consequently, in the heat transfer coefficient along the bearing chamber circumference. This largely determines the heat flow through the chamber wall. The proposed method of modeling workflow in the support's oil cavity is based on a mathematical notation of the heterogeneous monodisperse oil-air flow with an algorithm of inversion of the structure of two-phase flow in the near-wall region from the drip into the bubble. That makes it possible to more accurately calculate the temperature states of the GTE rotor support elements and the system that ensures the proper operation of the bearing by correctly determining the heat transfer coefficient on the part of the oil-air mixture. The constructed model makes it possible to numerically investigate the applicability of those known and to derive the new correlation dependences for the mean value of aheat transfer coefficientin the oil cavity of rotor support that is used in engineering calculations. The model also makes it possible to numerically investigate the impact of the geometry, the rotor rotation frequency, and the phases flow rates on heat output in the oil cavity

Magnetized ferrites are anisotropic materials used in passive non-reciprocal components. One of the main applications of ferrites at microwave frequencies is the isolation effect. In this work, the...

International audience; In this paper, a geometrical and thermodynamical analysis of the global properties of the potential energy landscape of a minimalistic model of a polypeptide is presented. The global geometry of the potential energy landscape is supposed to contain relevant information about the properties of a given sequence of amino acids, that is, to discriminate between a random heteropolymer and a protein. By considering the SH3 and PYP protein-sequences and their randomized versions it turns out that in addition to the standard signatures of the folding transition-discriminating between protein sequences of amino acids and random heteropolymer sequences-also peculiar geometric signatures of the equipotential hypersurfaces in configuration space can discriminate between proteins and random heteropolymers. Interestingly, these geometric signatures are the "shadows" of deeper topological changes that take place in correspondence with the protein folding transition. The protein folding transition takes place in systems with a small number of degrees of freedom (very far from the Avogadro number) and in the absence of a symmetry-breaking phenomenon. Nevertheless, seen from the deepest level of topology changes of equipotential submanifolds of phase space, the protein folding transition fully qualifies as a phase transition.

Graciá et al., Chelonians are among the animal groups with the poorest conservation status. Since tortoises are long-lived species that need very long time to reach sexual maturity, they are extremely vulnerable to human pressure. Despite their endangered status, there are no common strategies for the development of conservation actions. At the “Mediterranean workshop to develop tortoise conservation strategies”, scientists, conservation associations, environmental managers, IUCN advisers and CITES inspectors met in October 2019 in Alicante (Spain). The aims were to update the diagnosis of the conservation status of the Hermann’s tortoise (Testudo hermanni) and the spur-thighed tortoise (Testudo graeca) and to suggest strategies that guarantee their preservation at the Mediterranean Region. The main conclusions are summarized by: i) Mediterranean tortoises are wild endangered species that must be protected in, and together with, their natural habitat. Their main threats are habitat loss and fragmentation and pet trade, but we should also pay attention to wildfires, spread of diseases, the introduction of exotic species or lineages and climate change. ii) Long-term efforts and stablished protocols are needed to accurately diagnose and monitor the conservation status of wild populations, as well as flows among captive and wild animals. iii) Tortoise trade should be banned because it threatens the conservation of wild populations of tortoises. Illegal practices related to tortoises should be decidedly persecuted. People should consider tortoises as wild animals that are endangered and deserving of protection. It is possible to enjoy them by responsibly observing them in their habitat. iv) Tortoises may carry pathogens or parasites and their sanitary status cannot be fully assessed. They should always be considered potential vectors of tortoise diseases and of zoonosis. Hygiene protocols should be implemented when managing them. v) The researchers attending this workshop aimed to develop a scientific network for the long-term monitoring of graeca and T. hermanni populations in the Mediterranean Region. They will need the support from public administrations., The work of the researchers leading this work (EG, RCRC and AG) was funded by the Span‐ ish Ministry of Science through projects PID2019‐105682RA‐I00/AEI/10.13039/5011 00011033 and CGL2015‐64144 (the latter with the support of the European Regional Development Fund, MINECO/FEDER). MVJF and RCRC are supported by post‐doctoral grants funded by the Regional Valencian Government and the European Social Fund (APOSTD/2018/043 and APOSTD/2020/090, respectively).

This study is the first contribution to the evaluation of reptile diversity in different habitats of M’sila region, Algeria. We carried out 94 trips between 2016 and 2018 across three sites: Mergueb (six stations), L’mhazem (three stations) and Kaf Afoul (two stations), on average, accompanied by prospectors. Our aims were to make an inventory of reptilian species in this region, as well as to study their diversity, distribution, ecology and abundance. Altogether, we recorded 193 specimens belonging to 22 species: two turtles, one amphisbaenian, twelve lizards and seven snakes. Two species classified as Near Threatened by the IUCN were recorded: Uromastyx acanthinurus (Bell, 1825) and Daboia mauritanica (Duméril & Bibron, 1848). Statistical analysis revealed that the type of habitat directly influences the distribution of reptiles in the study area. Although this small area is rich in reptilian species, their abundance remains low and worrying

Phase transitions do not necessarily correspond to a symmetry-breaking phenomenon. This is the case of the Kosterlitz–Thouless (KT) phase transition in a two-dimensional classical XY model, a typical example of a transition stemming from a deeper phenomenon than a symmetry-breaking. Actually, the KT transition is a paradigmatic example of the successful application of topological concepts to the study of phase transition phenomena in the absence of an order parameter. Topology conceptually enters through the meaning of defects in real space. In the present work, the same kind of KT phase transition in a two-dimensional classical XY model is tackled by resorting again to a topological viewpoint, however focussed on the energy level sets in phase space rather than on topological defects in real space. Also from this point of view, the origin of the KT transition can be attributed to a topological phenomenon. In fact, the transition is detected through peculiar geometrical changes of the energy level sets which, after a theorem in differential topology, are direct probes of topological changes of these level sets.

Chaque texte est unique, et est en soi déjà la traduction d’un autre texte. Aucun texte n’est entièrement original car le langage lui-même dans son essence est déjà une traduction : d’abord du monde non verbal, et ensuite parce que chaque signe et chaque phrase sont à leur tour aussi une traduction d’un autre signe et d’une autre phrase qui ont précédé. On peut aussi inverser ceci et affirmer ce qui suit : tous les textes sont des originaux car chaque traduction est toujours distincte et diff...

Weathering of LDPE films was performed in a sub-Saharan facility in Laghouat, Algeria. Ageing led to a rapid change of the physicochemical properties resulting from the alteration of the material's microstructure. XRD revealed the progressive increase of the crystallinity ratio and the thickness of the crystalline lamellae as well. SEM revealed the presence of white particles, which look like crystalline phase emerging from the surface of the film. The oxidation and crystallinity varied according to a concentration gradient across the thickness. The impact of the microstructural changes on the mechanical properties was highlighted based on the essential work of fracture (EWF) method. There was a progressive decrease of the total energy of fracture and a lowering of the net stress (σnet) and the (βwp) term. Nevertheless, this loss of the mechanical properties was characterized by a rapid transition from a ductile mode of failure to a very brittle mode.

The achievement of quantum supremacy boosted the need for a robust medium of quantum information. In this task, higher-dimensional qudits show remarkable noise tolerance and enhanced security for quantum key distribution applications. However, to exploit the advantages of such states, we need a thorough characterisation of their entanglement. Here, we propose a measure of entanglement which can be computed either for pure and mixed states of a $M$-qudit hybrid system. The entanglement measure is based on a distance deriving from an adapted application of the Fubini-Study metric. This measure is invariant under local unitary transformations and has an explicit computable expression that we derive. In the specific case of $M$-qubit systems, the measure assumes the physical interpretation of an obstacle to the minimum distance between infinitesimally close states. Finally, we quantify the robustness of entanglement of a state through the eigenvalues analysis of the metric tensor associated with it., Comment: arXiv admin note: substantial text overlap with arXiv:1908.03117