A Secure Cooperative Sensing Protocol for Cognitive Radio Networks

Cognitive radio networks sense spectrum occupancyand manage themselves to operate in unused bands without disturbing licensed users. Spectrum sensing is more accurate if jointly performed by several reliable nodes. Even though cooperative sensing is an active area of research, the secureauthentication of local sensing reports remains unsolved, thus empowering false results. This paper presents a distributed protocol based on digital signatures and hash functions, and ananalysis of its security features. The system allows determining a final sensing decision from multiple sources in a quick and secure way.

Secure Dynamic MANET On-demand (SEDYMO) Routing Protocol

This paper describes the state of the art of secure ad hoc routing protocols and presents SEDYMO, a mechanism to secure a dynamic multihop ad hoc routing protocol. The proposed solution defeats internal and external attacks usinga trustworthiness model based on a distributed certification authority. Digital signatures and hash chains are used to ensure the correctness of the protocol. The protocol is compared with other alternatives in terms of security strength, energy efficiency and time delay. Both computational and transmission costs are considered and it is shown that the secure protocol overhead is not a critical factor compared to the high network interface cost.

Joint physical-MAC layer design of the broadcast channel protocol in adhoc networks

Broadcast transmission mode in ad hoc networks is critical to manage multihop routing or providing medium accesscontrol (MAC)-layer fairness. In this paper, it is shown that ahigher capacity to exchange information among neighbors may beobtained through a physical-MAC cross-layer design of the broadcastprotocol exploiting signal separation principles. Coherentdetection and separation of contending nodes is possible throughtraining sequences which are selected at random from a reducedset. Guidelines for the design of this set are derived for a lowimpact on the network performance and the receiver complexity.

Systematic review protocol to define classical IgE-associated diseases from birth to adolescence: the MeDALL study

BACKGROUND: Classical disease phenotypes are mainly based on descriptions of symptoms and the hypothesis that a given pattern of symptoms provides a diagnosis. With refined technologies there is growing evidence that disease expression in patients is much more diverse and subtypes need to be defined to allow a better targeted treatment. One of the aims of the Mechanisms of the Development of Allergy Project (MeDALL,FP7) is to re-define the classical phenotypes of IgE-associated allergic diseases from birth to adolescence, by consensus among experts using a systematic review of the literature and identify possible gaps in research for new disease markers. This paper describes the methods to be used for the systematic review of the classical IgE-associated phenotypes applicable in general to other systematic reviews also addressing phenotype definitions based on evidence. METHODS/DESIGN: Eligible papers were identified by PubMed search (complete database through April 2011). This search yielded 12,043 citations. The review includes intervention studies (randomized and clinical controlled trials) and observational studies (cohort studies including birth cohorts, case-control studies) as well as case series. Systematic and non-systematic reviews, guidelines, position papers and editorials are not excluded but dealt with separately. Two independent reviewers in parallel conducted consecutive title and abstract filtering scans. For publications where title and abstract fulfilled the inclusion criteria the full text was assessed. In the final step, two independent reviewers abstracted data using a pre-designed data extraction form with disagreements resolved by discussion among investigators. DISCUSSION: The systematic review protocol described here allows to generate broad,multi-phenotype reviews and consensus phenotype definitions. The in-depth analysis of the existing literature on the classification of IgE-associated allergic diseases through such a systematic review will 1) provide relevant information on the current epidemiologic definitions of allergic diseases, 2) address heterogeneity and interrelationships and 3) identify gaps in knowledge.

Recent advances in lamellarin alkaloids: isolation, synthesis and activity

Lamellarins are a large family of marine alkaloids with potential anticancer activity that have been isolated from diverse marine organisms, mainly ascidians and sponges. All lamellarins feature a 3,4-diarylpyrrole system. Pentacyclic lamellarins, whose polyheterocyclic system has a pyrrole core, are the most active compounds. Some of these alkaloids are potently cytotoxic to various tumor cell lines. To date, Lam-D and Lam-H have been identified as lead compounds for the inhibition of topoisomerase I and HIV-1 integrase, respectively nuclear enzymes which are over-expressed in deregulation disorders. Moreover,these compounds have been reported for their efficacy in treatment of multi-drug resistant (MDR) tumors cells without mediated drug efflux, as well as their immunomodulatory activity and selectivity towards melanoma cell lines. This article is an overview of recent literature on lamellarins, encompassing their isolation, recent synthetic strategies for their total synthesis, the preparation of their analogs, studies on their mechanisms of action, and their structure-activity relationships (SAR).

Efficacy of a dilemma-focused intervention for unipolar depression: study protocol for a multicenter randomized controlled trial

Background Depression is one of the more severe and serious health problems because of its morbidity, disabling effects and for its societal and economic burden. Despite the variety of existing pharmacological and psychological treatments, most of the cases evolve with only partial remission, relapse and recurrence. Cognitive models have contributed significantly to the understanding of unipolar depression and its psychological treatment. However, success is only partial and many authors affirm the need to improve those models and also the treatment programs derived from them. One of the issues that requires further elaboration is the difficulty these patients experience in responding to treatment and in maintaining therapeutic gains across time without relapse or recurrence. Our research group has been working on the notion of cognitive conflict viewed as personal dilemmas according to personal construct theory. We use a novel method for identifying those conflicts using the repertory grid technique (RGT). Preliminary results with depressive patients show that about 90% of them have one or more of those conflicts. This fact might explain the blockage and the difficult progress of these patients, especially the more severe and/or chronic. These results justify the need for specific interventions focused on the resolution of these internal conflicts. This study aims to empirically test the hypothesis that an intervention focused on the dilemma(s) specifically detected for each patient will enhance the efficacy of cognitive behavioral therapy (CBT) for depression. Design A therapy manual for a dilemma-focused intervention will be tested using a randomized clinical trial by comparing the outcome of two treatment conditions: combined group CBT (eight, 2-hour weekly sessions) plus individual dilemma-focused therapy (eight, 1-hour weekly sessions) and CBT alone (eight, 2-hour group weekly sessions plus eight, 1-hour individual weekly sessions). Method Participants are patients aged over 18 years meeting diagnostic criteria for major depressive disorder or dysthymic disorder, with a score of 19 or above on the Beck depression inventory, second edition (BDI-II) and presenting at least one cognitive conflict (implicative dilemma or dilemmatic construct) as assessed using the RGT. The BDI-II is the primary outcome measure, collected at baseline, at the end of therapy, and at 3- and 12-month follow-up; other secondary measures are also used. Discussion We expect that adding a dilemma-focused intervention to CBT will increase the efficacy of one of the more prestigious therapies for depression, thus resulting in a significant contribution to the psychological treatment of depression. Trial registration ISRCTN92443999; ClinicalTrials.gov Identifier: NCT01542957.

Isolation, structural assignment and total synthesis of Barmumycin

Barmumycin was isolated from an extract of the marine actinomycete Streptomyces sp. BOSC-022A and found to be cytotoxic against various human tumor cell lines. Based on preliminary one- and two-dimensional 1H- and 13C-NMR spectra, the natural compound was initially assigned the structure of macrolactone-type compound 1, which was later prepared by two different routes. However, major spectroscopic differences between isolated barmumycin and 1 led to revision of the proposed structure as E-16. Based on synthesis of this new compound, and subsequent spectroscopic comparison of it to an authentic sample of barmumycin, the structure of the natural compound was indeed confirmed as that of E-16.

Isolation and characterization of Saccharomyces cerevisiae mutants resistant to aculeacin A

Aculeacin A is a lipopeptide that inhibits ,B-glucan synthesis in yeasts. A number of Saccharomyces cerevisiae mutants resistant to this antibiotic were isolated, and four loci (ACRI, ACR2, ACR3, and ACR4) whose products are involved in the sensitivity to aculeacin A of yeast ceils were defined. Mutants containing mutations in the four loci were also resistant to echinocandin B, another member of this lipopeptide family of antibiotics. In contrast, acri, acr3, and acr4 mutants were resistant to papulacandin B (an antibiotic containing a disaccharide linked to two fatty acid chains that also inhibits P-glucan synthesis), but acr2 mutants were susceptible'to this antibiotic. This result defines common and specific steps in the entry and action of aculeacin A and papulacandin B. The analysis of double mutants revealed an epistatic effect of the acr2 mutation on the other three mutations. Cell walls of the four different mutants did not show significant alterations in composition with respect to the parental strain, and in vitro glucan synthase activity was also unaffected. However, cell surface hydrophobicity in three of the mutants was considerably decreased with respect to the parental strain.

Protocol per a la implantació d'eines didàctiques virtuals: competències i habilitats adquirides pels estudiants

L"adaptació al nou espai europeu d"educació superior (EEES) ha plantejat alguns canvis en l"enfocament de la formació universitària al nostre país. On abans era el docent el protagonista, ara és l"estudiant el que pren el rol d"actor principal de la seva formació, i l"aprenentatge s"orienta cap a una autonomia i reflexió més grans. En aquest escenari, les noves tecnologies ofereixen un ampli ventall d"opcions per millorar els processos formatius. En aquests sentit, el Grup d"Innovació Docent G IDEA ha participat activament en aquest procés d"adaptació des de ja fa uns quants anys, i ha creat una sèrie de recursos docents digitals que han estat àmpliament provats en diversos ensenyaments de la Facultat d"Economia i Empresa de la Universitat de Barcelona. L"objectiu d"aquest article és presentar el protocol dissenyat per l"equip d"investigadors del G IDEA per implantar aquestes eines didàctiques (webquestes i exercicis tutoritzats), i també els resultats d"una enquesta de satisfacció sobre les competències i habilitats adquirides pels nostres estudiants en la utilització dels recursos. Els resultats mostren, d"una banda, que no ha estat possible crear un mateix protocol aplicable a tots els recursos, a causa de les diferències en els objectius didàctics de les distintes eines docents implantades. D"altra banda, la valoració que els estudiants fan de la utilització de les eines és molt positiva, tot i que hi ha algunes diferències entre els recursos analitzats. Conèixer la valoració que l"alumnat fa d"aquests recursos permet al grup d"investigadors poder-los millorar i adequar al perfil dels estudiants perquè aquests en puguin treure el màxim profit possible.

Isolation, structural assignment and total synthesis of Barmumycin

Barmumycin was isolated from an extract of the marine actinomycete Streptomyces sp. BOSC-022A and found to be cytotoxic against various human tumor cell lines. Based on preliminary one- and two-dimensional 1H- and 13C-NMR spectra, the natural compound was initially assigned the structure of macrolactone-type compound 1, which was later prepared by two different routes. However, major spectroscopic differences between isolated barmumycin and 1 led to revision of the proposed structure as E-16. Based on synthesis of this new compound, and subsequent spectroscopic comparison of it to an authentic sample of barmumycin, the structure of the natural compound was indeed confirmed as that of E-16.

Protocol de conservació ex situ del Centre Ictiològic del Parc Natural del Delta de l'Ebre

En aquest Treball de Fi de Grau es pretén establir un protocol per a la conservació ex situ de les espècies que hi ha en el Centre Ictiològic del Parc Natural del Delta de l’Ebre. Les espècies que es troben en el CI són espècies vulnerables o en perill: espinós, samaruc, fartet, rabosa, llopet de riu i tritó palmat. Els objectius d’aquest protocol són: que el CI tingui un protocol propi, aprendre com funciona tot el centre, totes les espècies, com alimentar-les, com manipular-les i com tractar-les durant tot el seu cicle de vida. Un altre objectiu és el de veure si a finals d’any s’obté una alta població de cada espècie, quines són reintroduïdes, les patologies sorgides i els valors dels paràmetres químics de les basses naturals exteriors. El protocol s’elabora a partir de les pràctiques realitzades durant l’estiu del 2013 i els coneixements adquirits, la bibliografia i les dades del CI. Gràcies a això s’ha elaborat el treball. S’ha tractat la conservació ex situ; la problemàtica que sofreixen les espècies; cadascuna d’aquestes espècies; com funciona el CI a nivell de centre i a nivell de personal; les tasques que hi ha diàriament, setmanalment i ocasionalment segons les necessitats de l’estoc; el maneig sanitari; les patologies i com tractar-les; i l’anàlisi genètic. Els resultats obtinguts d’aquest protocol són els resultats numèrics obtinguts de l’any 2013 que són: 1. El gran nombre de cries nascudes de samaruc i fartet, menys de raboseta de riu, poques d’espinós i tritó palmat, i menys de llopet que tot just comença ara en el CI. 2. El total d’uns 5700 individus reitnroduits (samaruc, raboseta de riu i espinós de Girona). 3. La patologia més sorgida és el punt blanc. 4. I els paràmetres químics (amoni, nitrits, nitrats i fòsfor) no són molt elevats. La conclusió final i més important a la que arribo en fer el protocol és la gran importància que té el CI per a conservar aquestes espècies que no es saben apreciar fins que comencen a desparèixer. La existència del CI és més aviat una mesura correctora de tots els impactes que han sofert els habitatges de les espècies tractades i de la introducció d’espècies exòtiques que són una amenaça per les autòctones.

Avaluació de l'efecte causat sobre els valors de potència entre un protocol d'entrenament de càrregues baixes i un amb càrregues submàximes

L’objectiu d’aquest estudi és comparar els efectes que produeixen un protocol d’entrenament orientat amb càrregues lleugeres (40%-60% 1RM) i un protocol d’entrenament amb càrregues altes submàximes (90% 1RM), sobre els nivells de potència muscular. L’estudi ha analitzat a 12 futbolistes masculins pertanyents al mateix equip (22,1 ± 2,9 anys, 72,2 ± 6, 8 kg, 1,77 ± 0,15 m). Els exercicis analitzats foren el ½ squat i el press banca. També es va utilitzar un grup control. Els resultats ens van mostrar que el grup d’entrenament amb càrregues lleugeres va obtenir unes millores més considerables sobre els valors de potència (W) en 40% i 60% 1RM i per altre banda en el grup d’entrenament amb càrregues submàximes es van produir uns increments de potència més alts en càrregues altes (80% 1RM). Els resultats referents a la velocitat mitjana (m/s), es van produir de manera més considerable en el grup que va realitzar el treball amb càrregues lleugeres, en totes les intensitats analitzades.

A Forwarding Cooperation Protocol for Plain and Cluster-based Ad Hoc Networks

Peer-reviewed

Pilot study about the effect of rt-PA administration on the excitotoxicity mediated brain damage and its repercussion on the functional prognosis of patients with ischaemic stroke: research protocol

Fibrinolytic therapy with Recombinant Tissue-Plasminogen Activator (rt-PA) is currently the only effective treatment for ischaemic stroke in its acute phase. Even though its use generally improves the prognosis of those patients likely to receive it, rt-PA administration is associated to several risks, such as haemorrhagic transformation ofthe ischaemic lesion and activation of excitotoxic mechanisms that may contribute to an increase in mortality or to a poor outcome in certain occasions, specially when arterial recanalization is not achieved or the rt-PA is lately administrated. Since in the last few years the role of glutamate in the neurotoxicity associated toischaemia has been widely studied and it is known that high plasma glutamate levels are predictors of ischaemic lesion growth and poor neurological outcome, it is necessary to find out which factors can contribute to glutamate release in the brain. The aim of this study is to determine if rt-PA administration is related to an increase in plasma glutamate levels, as well as to define if higher plasma glutamate levels at admission are related to different evolution and prognosis of our patients, both in those in which recanalisation is achieved and not. A series of cases of patients with hemispheric cerebral infarction admitted in our hospital during a year will be studied, and the data obtained from them will be compared to the data obtained from a control group, the samples of wich were takenyears ago, before rt-PA was routinely used

The evolution of post-zygotic isolation barriers by immune-triggered hybrid incompatibilities in Arabidopsis thaliana

A long-standing question in evolutionary biology is what defines a species. The biological species concept considers a species as a population of individuals that interbreeds freely and produces viable offspring. Therefore, reproductive isolation is the essence of species. Hybrid necrosis is one form of post-zygotic reproductive isolation. In this chapter, we summarize what is known to date about this phenomenon and highlight progress made in the understanding of these immune-triggered hybrid incompatibilities through our research in the plant model Arabidopsis thaliana.