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In men, reduced levels of testosterone are associated with the prevalence and progression of multiple sclerosis (MS), a chronic and disabling demyelinating disorder. Testosterone has been shown to promote myelin repair. Here, we demonstrate that the cooperation between testosterone and CXCR4 signaling involving astrocytes is required for myelin regeneration after focal demyelination produced in the ventral mouse spinal cord by the infusion of lysolecithin. The testosterone-dependent remyelination of axons by oligodendrocytes was accompanied by an increase in astrocytes expressing CXCR4, its ligand CXCL12 and the androgen receptor (AR) within the demyelinated area. Depriving males of their testosterone or pharmacological inhibition of CXCR4, with the selective antagonist AMD3100, prevented the appearance of astrocytes expressing CXCR4, CXCL12 and AR within the demyelinated area and the concomitant recruitment of myelin forming oligodendrocytes. Conditional genetic ablation of either CXCR4 or AR in astrocytes also completely blocked the formation of new myelin by oligodendrocytes. Interestingly, the gain of function mutation in CXCR4 causing WHIM syndrome allows remyelination to take place, even in the absence of testosterone, but its potentiating effects remained observable. After testosterone deprivation or CXCR4 inhibition, the absence of astrocytes within the demyelinated area led to the incursion of Schwann cells, most likely derived from spinal nerves, and the formation of peripheral nerve type myelin. In patients with progressive MS, astrocytes expressing CXCR4 and AR surrounded myelin lesions, and their presence opposed the incursion of Schwann cells. These results highlight a mechanism of promyelinating testosterone signaling and the importance of normalizing its levels in combined myelin repair therapies.

Working in air navigation sector is as interesting as it is difficult and complicated. The technological change that this important field entails and the modernization of the system and equipment it uses, encourage not only the rationalization of procedures and their application, but also to take into account the risk factors that may hinder the work of operating personnel.  It should be noted that the pilot and the air traffic controller are engaged in an extremely complex task involving verbal exchanges of information and instructions, where stress is controlled on board, which is extremely dangerous due to the impact of this energy consumer on the physical and moral health of operating personnel. Indeed, a psycho-physiological reaction to a stimulus that caused the tension   involves a change in the metabolism of the professional, which the brunt on the safety of passengers, aircraft and air navigation installations is extremely perilous. Hence the need to establish a stress assessment discipline for operating personnel in order  to take in hand and clean up the causes of this energy-consumer., Travailler dans le secteur de la navigation aérienne  est une tâche  aussi agréable que contraignante, la mutation technologique que ce domaine impliquée et la modernisation du système et des équipements qu’il utilise, incitent non seulement à la rationalisation des procédures et leur application mais aussi à  la prise en compte des facteurs de risques qui peuvent entraver la tâche du personnel exploitant. Il faut noter  que le  pilote et le contrôleur  aérien  sont engagés dans une tâche éminemment complexe, impliquant des échanges verbaux d’informations et d’instructions où le stress est maitre à bord, ce  qui  est extrêmement dangereux vu l’impacte de ce consommateur d’énergie sur la santé physique et morale du personnel  de l’aviation. En effet,  une réaction psycho-physiologique à un agent stressant, engage un changement dans le métabolisme de l’ATC dont les répercussions  sont extrêmement  périlleuses sur la sécurité aussi bien des passagers, de l’avion et des Installations de la navigation aérienne, d’où la nécessité d’instaurer une discipline  d’évaluation du stress chez le personnel exploitant afin d’assainir les  causes de cet énergivore.

Data Envelopment Analysis (DEA) appears more than just an instrument of measurement. DEA models can be seen as a mathematical structure for democratic voicing within decisional contexts. Such an important aspect of DEA is enhanced through the performance evaluation of a group of professors in a virtual Business college. We show that the outcomes of the analysis can be very useful to support decision processes at many levels. There are three categories of professors: Assistant professors, Associate professors, and Full professors. The evaluation process of these professors is investigated through two different cases. The first case handles each category of professors as a separate sample representing an independent population. The results show that the mean efficiency scores fall between 0.85 and 0.93 for all professors no matters their category. In spite of enabling more fairness, such an approach suffers from its exclusive character, which is contrary to the democratic spirit of DEA. The second case tries to cope with this deficiency through the assessment of the faculty members as a single sample drawn from the same population, i.e., Assistant professors, Associate professors, and Full professors are treated equally, only on the ground of their respective inputs and outputs, no matters their academic rank. A clear efficiency decline is reported, basically due to the very nature of DEA as a procedure that is more efficiency than output focused.

Ecballium elaterium (squirting cucumber) is a Mediterranean plant used in folk medicine. Especially fruits and fruits juice are administered for several therapeutic uses, although they can be toxic at high doses. In the present work, a phytochemical characterization of different parts of the plant, namely fruits, flowers and leaves, was made. Extracts were analyzed by liquid chromatography coupled to diode array detector and mass spectrometry with triple quadrupole analyzer (HPLC-DAD-MS/MS). Only one cucurbitacin, Cuc D, was found in the three extracts, and an additional one, Cuc P, was tentatively identified for the first time in fruits extract. Additionally, several flavonoids such as rutin, narcissin and kaempferol were tentatively identified in the plant. Antioxidant activity was evaluated by DPPH, ABTS, FRAP and inhibition of human erythrocyte hemolysis mediated by AAPH. Results revealed that flowers extract was the most active one, with an EC50 of 46.01 µg/ml for DPPH and TEAC values of 489.11 and 160.97 µmol Trolox/g extract for ABTS and FRAP respectively; despite the protective effect of all extracts in AAPH assay was relatively moderated. In case of anti-inflammatory activity, all extracts were active by inhibiting heat induced protein denaturation in a non-dose dependent manner, showed protection against hypotonic hemolysis and reduction of mice hind paw edema, 3 h after carrageenan injection; as for previous tests, flowers extract exhibited the highest percentage of inhibition (82.93%) of hind paw edema at a dose of 200 mg/kg. Therefore, E. Elaterium flowers extract showed potential antioxidant and anti-inflammatory effects similar to those exerted by the fruits.

Multiple sclerosis (MS) is a chronic neurologic disease characterized by autoimmune destruction of myelin, a sheath-like material that insulates and protects nerve fibers. A significant portion of patients with MS experience severe chronic pain that is neuropathic in nature. Preclinical studies have recently demonstrated that a specific degradation product of myelin basic protein (MBP), one of the major targets of the autoimmune response in MS, is capable of producing neuropathic pain. In particular, MBP cryptic antigenic epitope, which is hidden in intact MBP, is exposed and released postnerve injury by the activity of matrix metalloproteinase 9 (MMP-9) and produces neuropathic pain. The purpose of our study is to determine if levels of the degradation product of MBP and antibodies against it correlate with the presence and severity of chronic neuropathic pain in patients with MS as well as to find out if levels of matrix metalloproteinase 9 in urine can be used as a marker of pain in MS patients.

Several very effective exact algorithms have been developed for vehicle routing problems with time windows. Unfortunately, most of these algorithms cannot be applied to instances that are defined on road networks, because they implicitly assume that the cheapest path between two customers is equal to the quickest path. Garaix and coauthors proposed to tackle this issue by first storing alternative paths in an auxiliary multi-graph, and then using that multi-graph within a branch-and-price algorithm. We show that, if one works with the original road network rather than the multi-graph, then one can solve the pricing subproblem more quickly, in both theory and practice.

The capacitated arc routing problem (CARP) is a well-known and fundamental vehicle routing problem. A promising exact solution approach to the CARP is to model it as a set covering problem and solve it via branch-cut-and-price. The bottleneck in this approach is the pricing (column generation) routine. In this paper, we note that most CARP instances arising in practical applications are defined on sparse graphs. We show how to exploit this sparsity to yield faster pricing routines. Extensive computational results are given.

As globalisation is not anymore a dream or a simple idea, but a real and hard fact, a number of important aspects are becoming strategic issues. Among others, one could namely mention the out-borders transfer of goods, services, funds or capital, technology, manpower, information and scientific and technological knowledge. Obviously, industrial firms, business companies, financial, educational and research institutions are all and directly concerned.As the act of management implies necessarily taking decisions about all activities concerning all forms of organisations, overall performance could not be high, thus the integration into the world economy successful, unless if decisions makers are themselves well trained and armed. This should imply the following requirements: Acquiring modern conceptual tools; Being aware of best practice techniques; Having good imagination and wide culture; And mastering a number of languages. Henceforth, a high quality management education, both in public and private institutions, becomes absolutely essential. Consequently, any graduate lacking such requirements would be a bad manager of the future.The present author has a relatively long teaching experience in management sciences and managerial economics; He also has some deep thoughts about inadequacies of management training, in some of theMaghrebcountries, to the present global market conditions. On this basis, he wishes to make a modest contribution to how performances of both management schools and actually trained and future business managers should be improved in order to successfully face the challenges of the next century. In essence, he believes that the opening of private business schools in developing countries cannot be left to become a matter of financial opportunities or a simple privatisation issue. The content of courses and the teaching methods are critical questions.

En Algérie, la mouche méditerranéenne des fruits, #Ceratitis capitata#, est le principal obstacle à la production et l'exportation de fruits. En étudiant les différences de structures génétiques entre populations de mouches des fruits à partir de marqueurs moléculaires, certains auteurs ont observé l'existence de comportements différents parmi les populations méditerranéennes du ravageur. Une bonne compréhension de l'origine et de la migration de l'insecte serait utile pour entreprendre son éradication ou adopter des mesures de contrôle. Pour cette raison, des travaux préliminaires ont cherché à comparer la structure génétique de populations algériennes de #C. capitata# avec celle d'autres populations localisées ou dans l'ouest de l'océan Indien, ou sur le littoral nord-ouest de la Méditerranée. L'étude du polymorphisme enzymatique de #C. capitata# a permis de comparer la structure génétique de quatre populations d'Algérie avec celle de l'île de la Réunion et cinq autres populations prélevées sur la côte nord-ouest de la Méditerranée (France et Espagne). Des analyses d'enzymes ont été effectuées sur des broyats d'insectes adultes étudiés par électrophorèse sur gels d'amidon. Quinze loci ont été analysés pour chaque population. Malgré la large distribution géographique des populations analysées (lat. 24° à 42° N), aucun gradient des loci polymorphes n'est apparu. Une plus forte variabilité génétique a été observée pour la population de l'île de la Réunion que pour celles localisées en Algérie ou sur la côte nord-ouest de la Méditerranée. Il n'existe pas de différentiation génétique entre les populations isolées du sud de l'Algérie (Djanet et Ghardaïa) et celles situées au nord (Boufarik et Oran).