Rendezvous of Two Robots with Constant Memory

We study the impact that persistent memory has on the classical rendezvous problem of two mobile computational entities, called robots, in the plane. It is well known that, without additional assumptions, rendezvous is impossible if the entities are oblivious (i.e., have no persistent memory) even if the system is semi-synchronous (SSynch). It has been recently shown that rendezvous is possible even if the system is asynchronous (ASynch) if each robot is endowed with O(1) bits of persistent memory, can transmit O(1) bits in each cycle, and can remember (i.e., can persistently store) the last received transmission. This setting is overly powerful. In this paper we weaken that setting in two different ways: (1) by maintaining the O(1) bits of persistent memory but removing the communication capabilities; and (2) by maintaining the O(1) transmission capability and the ability to remember the last received transmission, but removing the ability of an agent to remember its previous activities. We call the former setting finite-state (FState) and the latter finite-communication (FComm). Note that, even though its use is very different, in both settings, the amount of persistent memory of a robot is constant. We investigate the rendezvous problem in these two weaker settings. We model both settings as a system of robots endowed with visible lights: in FState, a robot can only see its own light, while in FComm a robot can only see the other robot's light. We prove, among other things, that finite-state robots can rendezvous in SSynch, and that finite-communication robots are able to rendezvous even in ASynch. All proofs are constructive: in each setting, we present a protocol that allows the two robots to rendezvous in finite time.Comment: 18 pages, 3 figure

Update of alien fauna and new records from Tunisian marine waters

An updated inventory of alien marine fauna in coastal and offshore Tunisian waters is presented. Records were compiled from scientific and ‘grey’ publications, presentations at scientific meetings, theses presented in fulfillment of requirements towards MSc and PhD degrees, websites and personal observations. 136 alien species were recorded in Tunisian waters, 60 records in northern coasts, West Mediterranean and 76 in central and southern coasts, Central Mediterranean. Nearly half of the first sightings in Tunisian waters took place in the Gulf of Gabès. The dominant taxa are Crustancean (24%), Molluscs (23%), Fishes (19%) and Annelida (13%). Twenty one species previously reported as aliens, were upon consideration, reclassified as range-expanding Atlantic species. Amathia verticillata, previously considered native to the Mediterranean, is reclassified as pseudoindigenous. Twenty one alien species are newly recorded from Tunisia, including 5 fish species, 5 polychaetes, 4 crustaceans, 4 molluscs, and one each schyphozoan, bryozoan and tunicate. The findings of Gibberulus gibberulus albus, Morula aspera and Calcinus latens, three species new to the Mediterranean, and of Actaedoes tomentosus, reported for the second time in the basin, are described. Species were classified according to their establishment status and their origins. This contribution highlights the dual origin of biological invasion in Tunisian waters (Red Sea and Atlantic), with slightly more species of Red Sea and Indo-Pacific origin (61,76%).  The impact of the alien species in Tunisian waters was discussed

The effects of cognitive behavioral therapy on selected physical, physiological parameters, exercise and nutritional behaviors in diabetic persons

OBJECTIVE Due to the high prevalence of diabetes in the world, it seems that one of the most important strategies to prevent and treat this disease are lifestyle changes. The present study aimed to investigate the effects of cognitive behavioral therapy on selected physical and psychological parameters, exercise, and nutritional behaviors in diabetic patients. PATIENTS AND METHODS This was a cross-sectional study of volunteers with type 2 diabetes. Patients were randomized into two groups: an intervention (n=32) and a control group (n=31). The Beck Physical Activity Questionnaire was used to assess physical activity in combination with the Beck Depression Inventory and the Pittsburgh Sleep Quality Index to assess the levels of depression and the quality of sleep. Cognitive behavior therapy (CBT) training consisted of six sessions of cognitive behavioral therapy interventions. The intervention consisted of a face-to-face individual counseling session. The patients received a special diet according to their basal metabolic rate (BMR). At all sessions, dietary advice was reviewed, and during the treatment period, they were asked to record their diet and physical activity. Body composition and blood samples were measured before and after three months of the experiment for both groups. RESULTS Blood glucose, blood lipid profiles (except high-density lipoprotein), lifestyle, behavior patterns and body composition were significantly improved following CBT intervention (p≤0.05). CONCLUSIONS CBT can play a key role in improving physiological and psychological parameters in diabetic patients

Les barotraumatismes de l’oreille moyenne

Objectif : Le barotraumatisme de l’oreille moyenne est une entité pathologique particulière rare et spécifique.Matériel et méthodes : Nous rapportons une série rétrospective de 13 cas de barotraumatismes de l’oreille moyenne diagnostiqués et suivis au centre d’expertise et de médecine aéronautique de Tunis.Résultats : L’âge moyen de nos patients est de 34 ans. Les signes fonctionnels étaient dominés par l’otalgie et l’hypoacousie. L’atteinte était bilatérale dans deux cas. Il s’agissait d’atteinte bénigne de stade (I et II) chez huit patients et d’épanchement rétrotympanique dans quatre cas. Une perforation tympanique a été observée chez un seul pilote. Le bilan clinique a permis de mettre en évidence la présence de circonstances favorisantes à la survenue du barotraumatisme dans neuf cas. Sur le plan fonctionnel, nous avons observés quatre barotraumatismes à audition conservée .Par ailleurs, La surdité était de type transitionnelle. La prise en charge thérapeutique était fonction du bilan lésionnel. L’évolution était favorable chez neufs patients avec une récupération auditive totale.Une dispense de vol fût proclamée dans tous les cas. La durée  d’inaptitude initiale était fonction du bilan lésionnel anatomique et fonctionnel et a variée entre dix et soixante jours.Mots-clés : Barotraumatisme, Surdité, Oreille moyenne, Pilote

Mal de pott révelé par un abcès latéropharyngien chez un pilote

Introduction: Pott's disease is the most frequent localisation of osteoarticular tuberculosis. The authors report a case of cervical Pott's disease with lateropharyngeal abscess.Observation: Our patient is a 44 years old pilot; he presented since 6 months cervicalgy, dysphagia and weighting loss.  Clinical findings showed a swelling of posterior and lateral oropharyngeal wall extending to hypopharynx. A palsy of the XI th nerve and an abolition of the bicipital reflex were also noticed. CT scan showed a lateropharyngeal collection extending from C4 to D1. It was also noticed a subtotal destruction of C6.However, there were no medullar lesions in the cervical spine MRI.Tuberculosis was confirmed thanks to histological analysis of caseum taken during cervical biopy. The patient was operated using anterior approach. He had surgical removal of C6 which was replaced by iliac prothesis. Medical treatment was based on antituberculosis drugs used during 12 months. After three years of follow up, the out come was favourable with no recurrence and satisfying consolidation. For aeronautic considerations, the patient was declared unable for flying mission.Conclusion: Tuberculosis constitutes a problematic infectious disease in Tunisia which may have serious consequences on publish health. We insist on preventing measurements because there are neither specific clinical findings nor radiological characterising features.Keywords: Tuberculosis, Pott's disease, lateropharyngeal absces

Self-stabilizing Deterministic Gathering

In this paper, we investigate the possibility to deterministically solve the gathering problem (GP) with weak robots (anonymous, autonomous, disoriented, deaf and dumb, and oblivious). We introduce strong multiplicity detection as the ability for the robots to detect the exact number of robots located at a given position. We show that with strong multiplicity detection, there exists a deterministic self-stabilizing algorithm solving GP for n robots if, and only if, n is odd

Pseudomonas rhizophila S211, a New Plant Growth-Promoting Rhizobacterium with Potential in Pesticide-Bioremediation

A number of Pseudomonas strains function as inoculants for biocontrol, biofertilization, and phytostimulation, avoiding the use of pesticides and chemical fertilizers. Here, we present a new metabolically versatile plant growth-promoting rhizobacterium, Pseudomonas rhizophila S211, isolated from a pesticide contaminated artichoke field that shows biofertilization, biocontrol and bioremediation potentialities. The S211 genome was sequenced, annotated and key genomic elements related to plant growth promotion and biosurfactant (BS) synthesis were elucidated. S211 genome comprises 5,948,515 bp with 60.4% G+C content, 5306 coding genes and 215 RNA genes. The genome sequence analysis confirmed the presence of genes involved in plant-growth promoting and remediation activities such as the synthesis of ACC deaminase, putative dioxygenases, auxin, pyroverdin, exopolysaccharide levan and rhamnolipid BS. BS production by P. rhizophila S211 grown on olive mill wastewater based media was effectively optimized using a central-composite experimental design and response surface methodology (RSM). The optimum conditions for maximum BS production yield (720.80 ± 55.90 mg/L) were: 0.5% (v/v) inoculum size, 15% (v/v) olive oil mill wastewater (OMWW) and 40◦C incubation temperature at pH 6.0 for 8 days incubation period. Biochemical and structural characterization of S211 BS by chromatography and spectroscopy studies suggested the glycolipid nature of the BS. P. rhizophila rhamnolipid was stable over a wide range of temperature (40–90◦C), pH (6–10), and salt concentration (up to 300mM NaCl). Due to its low-cost production, emulsification activities and high performance in solubilization enhancement of chemical pesticides, the indigenous BS-producing PGPR S211 could be used as a promising agent for environmental bioremediation of pesticide-contaminated agricultural soils

Production of seafood flavour formulations from enzymatic hydrolysates of fish by-products

© 2015 Published by Elsevier Ltd. Amino acid-rich extracts derived from fish by-products were utilised to generate flavour model systems with added glucose and/or fish oil. Combination of endo and exo peptidases resulted in the most marked increased in free amino acids, particularly for leucine, lysine and glutamic acid (48.3 ± 3.4 to 1423.4 ± 59.6, 43.3 ± 1.2 to 1485.4 ± 25.6 and 143.6 ± 21.7 to 980.9 ± 63.6 μg/g respectively).Main volatile products formed after heating the systems were 4-heptenal, 2,4-heptadienal, and some pyrazines. Increased concentrations of 1-octen-3-ol or 1-hepten-4-ol were also observed in the heated systems compared to the controls. All of these volatile compounds have been identified among the volatile profile of cooked seafood. Conversion of low value fish derived materials such as fish powder, into more valuable products such as flavour precursors and subsequently flavour compounds might be a commercially viable proposition for the fish industry

New Mediterranean Marine biodiversity records (June 2013)

This paper concerns records of species that have extended their distribution in the Mediterranean Sea. The finding of the rare brackish angiosperm Althenia filiformis in the island of Cyprus is interesting since its insertion in the Red Data Book of the Flora of Cyprus is suggested. The following species enriched the flora or fauna lists of the relevant countries: the red alga Sebdenia dichotoma (Greece), the hydrachnid mite Pontarachna adriatica (Slovenia), and the thalassinid Gebiacantha talismani (Turkey). Several alien species were recorded in new Mediterranean localities. The record of the burrowing goby Trypauchen vagina in the North Levantine Sea (Turkish coast), suggests the start of spreading of this Lessepsian immigrant in the Mediterranean Sea. The findings of the following species indicate the extension of their occurrence in the Mediterranean Sea: the foraminifer Amphistegina lobifera (island of Zakynthos, Greece), the medusa Cassiopea andromeda (Syria), the copepod Centropages furcatus (Aegean Sea), the decapod shrimp Melicertus hathor (island of Kastellorizo, Greece), the crab Menoethius monoceros (Gulf of Tunis), the barnacles Balanus trigonus, Megabalanus tintinnabulum, Megabalanus coccopoma and the bivalves Chama asperella, Cucurbitula cymbium (Saronikos Gulf, Greece)

NF-κB: A lesson in family values

A set of mobile robots (represented as points) is distributed in the Cartesian plane. The collection contains an unknown subset of byzantine robots which are indistinguishable from the reliable ones. The reliable robots need to gather, i.e., arrive to a configuration in which at the same time, all of them occupy the same point on the plane. The robots are equipped with GPS devices and at the beginning of the gathering process they communicate the Cartesian coordinates of their respective positions to the central authority. On the basis of this information, without the knowledge of which robots are faulty, the central authority designs a trajectory for every robot. The central authority aims to provide the trajectories which result in the shortest possible gathering time of the healthy robots. The efficiency of a gathering strategy is measured by its competitive ratio, i.e., the maximal ratio between the time required for gathering achieved by the given trajectories and the optimal time required for gathering in the offline case, i.e., when the faulty robots are known to the central authority in advance. The role of the byzantine robots, controlled by the adversary, is to act so that the gathering is delayed and the resulting competitive ratio is maximized. The objective of our paper is to propose efficient algorithms when the central authority is aware of an upper bound on the number of byzantine robots. We give optimal algorithms for collections of robots known to contain at most one faulty robot. When the proportion of byzantine robots is known to be less than one half or one third, we provide algorithms with small constant competitive ratios. We also propose algorithms with bounded competitive ratio in the case where the proportion of faulty robots is arbitrary