Maximum likelihood estimation of position in GNSS

In this letter, we obtain the Maximum LikelihoodEstimator of position in the framework of Global NavigationSatellite Systems. This theoretical result is the basis of a completelydifferent approach to the positioning problem, in contrastto the conventional two-steps position estimation, consistingof estimating the synchronization parameters of the in-viewsatellites and then performing a position estimation with thatinformation. To the authors’ knowledge, this is a novel approachwhich copes with signal fading and it mitigates multipath andjamming interferences. Besides, the concept of Position–basedSynchronization is introduced, which states that synchronizationparameters can be recovered from a user position estimation. Weprovide computer simulation results showing the robustness ofthe proposed approach in fading multipath channels. The RootMean Square Error performance of the proposed algorithm iscompared to those achieved with state-of-the-art synchronizationtechniques. A Sequential Monte–Carlo based method is used todeal with the multivariate optimization problem resulting fromthe ML solution in an iterative way.

Space-time front-ends for RAKE receivers in the FDD mode of UTRA

A unified and general vision of different space-time processors is presented. Many popular receivers can beaccomodated, like V-RAKE receivers, weighted V-RAKE, or spatial narrowband beamforming. By makingappropriate assumptions on the space/time characteristic of the interference it is possible to enhance theperformance of the receiver through spatial/temporal pre-processors. These receivers will be tested in the FDDmode of UTRA.

Performance Evaluation of Six-Sectored Configuration in Hexagonal WCDMA (UMTS) Cellular Network Layout

The objective of this master's thesis is to evaluate the optimum performance of sixsectored hexagonal layout of WCDMA (UMTS) network and analyze the performance at the optimum point. The maximum coverage and the maximum capacity are the main concern of service providers and it is always a challenging task for them to achieve economically. Because the optimum configuration of a network corresponds to a configuration which minimizes the number of sites required to provide a target service probability in the planning area which in turn reduces the deployment cost. The optimum performance means the maximum cell area and themaximum cell capacity the network can provide at the maximum antenna height satisfying the target service probability. Hexagon layout has been proven as the best layout for the cell deployment. In this thesis work, two different configurations using six-sectored sites have been considered for the performance comparison. In first configuration, each antenna is directed towards each corner of hexagon, whereas in second configurationeach antenna is directed towards each side of hexagon. The net difference in the configurations is the 30 degree rotation of antenna direction. The only indoor users in a flat and smooth semi-urban environment area have been considered for the simulation purpose where the traffic distribution is 100 Erl/km2 with 12.2 kbps speech service having maximum mobile speed of 3 km/hr. The simulation results indicate that a similar performance can be achieved in both the configurations, that is, a maximum of 947 m cellrange at antenna height of 49.5 m can be achieved when the antennas are directed towards the corner of hexagon, whereas 943.3 m cell range atantenna height of 54 m can be achieved when the antennas are directed towards the side of hexagon. However, from the interference point of view the first configuration provides better results. The simulation results also show that the network is coverage limited in both the uplink and downlink direction at the optimum point.

egr-4, a target of EGFR signaling, is required for the formation of the brian primordial and head regeneration in planarians

During the regeneration of freshwater planarians, polarity and patterning programs play essential roles in determining whether a head or a tail regenerates at anterior or posterior-facing wounds. This decision is made very soon after amputation. The pivotal role of the Wnt/β-catenin and Hh signaling pathways in re-establishing anterior-posterior (AP) polarity has been well documented. However, the mechanisms that control the growth and differentiation of the blastema in accordance with its AP identity are less well understood. Previous studies have described a role of Smed-egfr-3, a planarian epidermal growth factor receptor, in blastema growth and differentiation. Here, we identify Smed-egr-4, a zinc-finger transcription factor belonging to the early growth response gene family, as a putative downstream target of Smed-egfr-3. Smed-egr-4 is mainly expressed in the central nervous system and its silencing inhibits anterior regeneration without affecting the regeneration of posterior regions. Single and combinatorial RNA interference to target different elements of the Wnt/β-catenin pathway, together with expression analysis of brain- and anterior-specific markers, revealed that Smed-egr-4: (1) is expressed in two phases - an early Smed-egfr-3-independent phase and a late Smed-egfr-3-dependent phase; (2) is necessary for the differentiation of the brain primordia in the early stages of regeneration; and (3) that it appears to antagonize the activity of the Wnt/β-catenin pathway to allow head regeneration. These results suggest that a conserved EGFR/egr pathway plays an important role in cell differentiation during planarian regeneration and indicate an association between early brain differentiation and the proper progression of head regeneration.

The DNA damage response to adeno-associated virus : centrosome overduplication and induction of cell death independently of the spindle checkpoint

Summary: Adeno-associated virus type 2 (AAV2) is a small virus containing single-stranded DNA of approximately 4.7kb in size. Both ends of the viral genome are flanked with inverted terminal repeat sequences (ITRs), which serve as primers for viral replication. Previous work in our laboratory has shown that AAV2 DNA with ultraviolet radiation-generated crosslinks (UV-AAV2) provokes a DNA damage response in the host cell by mimicking a stalled replication fork. Infection of cells with UV-AAV2 leads to a p53-and Chk1-mediated cell cycle arrest at the G2/M border of the cell cycle. However, tumour cells lacking the tumour suppressor protein p53 cannot sustain this arrest and enter a prolonged impaired mitosis, the outcome of which is cell death. The aim of my thesis was to investigate how UV-inactivated AAV2 kilts p53-deficient cancer cells. I found that the UV-AAV2-induced DNA damage signalling induces centriole overduplication in infected cells. The virus is able to uncouple the centriole duplication cycle from the cell cycle, leading to amplified centrosome numbers. Chk1 colocalises with centrosomes in the infected cells and the centrosome overduplication is dependent on the presence of Chk1, as well as on the activities of ATR and Cdk kinases and on the G2 arrest. The UV-AAV2-induced DNA damage signalling inhibits the degradation of cyclin B 1 and securin by the anaphase promoting complex, suggesting that the spindle checkpoint is activated in these mitotic cells. Interference with the spindle checkpoint components Mad2 and BubR1 revealed that the UV-AAV2-provoked mitotic catastrophe occurs independently of spindle checkpoint function, This work shows that, in the p53 deficient cells, UV-AAV2 triggers mitotic catastrophe associated with a dramatic Chk1-dependent overduplication of centrioles and the consequent formation of multiple spindle poles in mitosis. Résumé Le virus associé à l'adénovirus type 2 (AAV2) est un petit virus contenant un simple brin d'ADN d'environ 4.7kb. Des expériences antérieures dans notre laboratoire ont montré que les liens intramoléculaires sur l'ADN de AAV2 provoqués paz l'irradiation aux ultraviolets (UV) ressemblent à une fourche de réplication bloquée, ce qui provoque une réponse aux dommages à l'ADN dans la cellule hôte. L'infection des cellules avec UV-AAV2 résulte en un arrêt du cycle cellulaire à la transition G2/M entraîné par les protéines ATR et Chk1. Cependant, les cellules tumorales auxquelles il manque le suppresseur de tumeur p53 ne peuvent pas tenir cet arrêt et entrent dans une mitose anormale et prolongée qui se terminera par la mort cellulaire. Le but de ma thèse était d'étudier comment l'AAV2 inactivé par l'irradiation UV tue les cellules cancéreuses n'ayant pas p53. Je montre ici que le signal de dommages à l'ADN induit par UV-AAV2 génère une surduplication des centrioles dans les cellules infectées. Le virus est capable de dissocier le cycle de duplication du centriole du cycle cellulaire ce qui crée un nombre amplifié de centrosomes. Chk1 est co-localisé avec le centrosome dans les cellules infectées et la swduplication du centrosome est dépendante de la présence de Chk1, de l'activité des kinases ATR et Cdk et de l'arrêt en G2 de la cellule. Le signal d'ADN endommagé induit par UV-AAV2 réprime la dégradation des protéines cycline B1 et securine par le complexe promoteur de l'anaphase (APC), ce qui suggère que le point de contrôle du fuseau mitotique est activé dans ces cellules en mitose. L'étude d'interférence avec des éléments du point de contrôle du fuseau mitotique, Mad2 et BubR1, a révélé que la catastrophe mitotique provoquée paz UV-AAV2 survient indépendamment du point de contrôle du fuseau mitotique. Ce travail montre que dans les cellules déficientes en p53, UV-AAV2 induit une catastrophe mitotique associée à une surduplication des centrioles dépendant de Chk1 et ayant pour conséquence dramatique la formation de multiples fuseaux mitotiques dans la cellule en mitose.

Procedures for evaluating the tolerance of cassava genotypes to postharvest physiological deterioration

Abstract: The objective of this work was to define procedures to assess the tolerance of cassava genotypes to postharvest physiological deterioration (PPD) and to microbial deterioration (MD). Roots of six cassava genotypes were evaluated in two experiments, during storage under different environmental conditions: high temperature and low soil moisture; or low temperature and high soil moisture. Roots were treated or not with fungicide (carbendazim) before storage. Genotype reactions to MD and PPD were evaluated at 0, 2, 5, 10, 15, 20, and 30 days after harvest (DAH), in the proximal, medial, and distal parts of the roots. A diagrammatic scale was proposed to evaluate nonperipheral symptoms of PPD. Fungicide treatment and root position did not influence PPD expression; however, all factors had significant effect on MD severity. Genotypes differed as to their tolerance to PPD and MD. Both deterioration types were more pronounced during periods of higher humidity and lower temperatures. The fungicide treatment increased root shelf life by reducing MD severity up to 10 DAH. Whole roots showed low MD severity and high PPD expression up to 10 DAH, which enabled the assessment of PPD without significant interference of MD symptoms during this period.

Perceptual defense in anxiety disorders

RÉSUMÉ Plusieurs auteurs ont étudié la perception en fonction de la psychopathologie. Dans cette optique, Borgeat, David, Saucier et Dumont en 1994 et Borgeat, Sauvageau, David et Saucier en 1997 ont utilisé la méthode tachistoscopique afin de comparer, dans une étude prospective, la perception de stimuli émotionnels entre des femmes souffrant d'une dépression du post- partum et des femmes non atteintes. Par ailleurs, des études antérieures, notamment les travaux de MacLeod et Rutherford en 1992, avaient montré la possibilité d'un processus de perception différent entre sujets anxieux et non anxieux. L'étude actuelle pose l'hypothèse d'une interaction entre caractéristiques du stimulus et trouble anxieux du sujet. Cette hypothèse suppose donc un processus préconscient de l'information, avec analyse sémantique de cette dernière, à même d'influencer (inhiber ou faciliter) la perception de certains stimuli en fonction de leur charge affective. L'étude que nous présentons a pour but d'évaluer la perception de stimuli anxiogènes chez les patients atteints de troubles anxieux, et plus particulièrement chez des sujets souffrant d'attaque de panique et de troubles obsessionnels-compulsifs. A cette fin, nous avons choisi, contrairement à la plupart des études effectuées jusqu'à présent où la méthode Stroop avait été utilisée, la technique tachistoscopique qui, à notre avis, permet une mesure plus directe de la rapidité du processus perceptuel. Ainsi, trois groupes de sujets ont pris part à l'étude : un groupe contrôle (N = 22), un groupe de patients souffrant d'attaques de panique (N = 21) et un groupe de patients atteints de troubles obsessionnels-compulsifs (N = 20). Ces 63 sujets, âgés entre 18 et 60 ans, ont à la fois répondu au Fear Questionnaire ainsi qu'au Questionnaire Beck 13 pour la dépression et procédé à la reconnaissance de 42 mots (six groupes de sept mots) présentés aléatoirement à l'ordinateur, en cycles successifs de 15 millisecondes. Cinq parmi les six groupes de mots se référaient à un trouble anxieux spécifique, le sixième étant considéré comme un groupe de mots « neutres ». Le temps, en millisecondes, nécessaire à la reconnaissance de chaque mot a été enregistré. Les résultats montrent une lenteur de la part des patients souffrant d'attaques de panique pour la reconnaissance de tous les stimuli par rapport aux sujets contrôle, avec une performance intermédiaire entre les deux groupes pour les patients atteints de troubles obsessionnels-compulsifs. De plus, l'analyse statistique a révélé deux effets d'interaction : les patients atteints d'attaques de panique sont plus rapides à reconnaître le groupe de mots en rapport avec leur angoisse, de même que les patients soufflant de troubles obsessionnels- compulsifs ont un temps moyen de reconnaissance des mots en rapport avec leur trouble plus bas que prévu. Ces résultats amènent à une double conclusion. La première est que les patients anxieux manifestent une défense perceptuelle globale face aux stimuli anxiogènes en général, et que cette défense est plus marquée chez les patients atteints d'attaques de panique que chez les sujets souffrant de troubles obsessionnels-compulsifs. La deuxième est que ces mêmes patients, confrontés à des stimuli en rapport avec leur propre angoisse, montrent une vigilance accrue. Ainsi, ces données évoquent une double stratégie de traitement de l'information chez les patients anxieux : un évitement perceptuel général face à l'information émotionnellement chargée, et un traitement sélectif de l'information ayant un rapport direct avec l'angoisse dont ils soufflent. SUMMARY Prior research by MacLeod and Rutherford (1992) indicates that anxious subjects could have perceptual strategies different from nonanxious subjects. 42 verbal stimuli of six types (disease, social anxiety, panic, agoraphobia, obsessive-compulsive, and neutral) were tachistoscopically presented to three groups of subjects, aged 18 to 60 years: Panic Disorder group (n =21: 13 women and 8 men), and Obsessive-Compulsive Disorder group (n=20: 14 women and 6 men), recruited from an outpatient clinic, and a Control group (n=22: 14 women and 8 men), recruited among students and hospital staff. The times required for correct identification were generally longer for anxious subjects but quicker for stimuli specifically related to their disorder. The data could indicate a two-step perceptual strategy or two distinct ways of perceiving, usually, a generalized perceptual defense for a majority of anxiety-loaded stimuli, but also a selectively facilitated processing for stimuli specific to the disorder.

Effects of nasal continuous airway pressure on pulmonary and systemic output in preterm infants

Objective: Respiratory assistance with nasal continuous positive airway pressure (n-CPAP) is an effective treatment in premature newborns presenting respiratory distress. The aim of the study was to depict cardiac function, systemic (Qs) and pulmonary output (Qp) by echocardiography in stable premature infants requiring prolonged n-CPAP. Our hypothesis was that n-CPAP could reduce pulmonary blood flow. Patients and methods: All premature infants < 32 weeks gestation, > 7 days-old, requiring n-CPAP without severe respiratory compromise nor need for additional oxygen were prospectively included. Every patient had a first echocardiography while on n-CPAP. N-CPAP was then discontinued for two hours and a second echocardiography was performed. Results: 17 premature infants were included. Mean gestational age was 28 ± 2 weeks and mean weight 1.1 ± 0.3 kg. Following retrieval of n-CPAP we observed an increase in Qp of 53 ml/kg/min (95% CI 19-87 ml/kg/min), but no significant change in Qs. Consecutively a significant increase in Qp/Qs ratio of 16% was found (95% CI 7-29%). Conclusions: Nasal continuous positive airway pressure has hemodynamic effects in preterm infants in stable pulmonary and cardiac conditions. It reduces pulmonary output without interference with systemic output.

Sliding Mode Control for Switched Mode Power Supplies

Control applications of switched mode power supplies have been widely investigated. The main objective ofresearch and development (R&D) in this field is always to find the most suitable control method to be implemented in various DC/DC converter topologies. Inother words, the goal is to select a control method capable of improving the efficiency of the converter, reducing the effect of disturbances (line and load variation), lessening the effect of EMI (electro magnetic interference), and beingless effected by component variation. The main objective of this research work is to study different control methods implemented in switched mode power supplies namely (PID control, hysteresis control, adaptive control, current programmed control, variable structure control (VSC), and sliding mode control (SMC). The advantages and drawbacks of each control method are given. Two control methods, the PID and the SMC are selected and their effects on DC/DC (Buck, Boost, and Buck-Boost) converters are examined. Matlab/SimulinkTM is used to implement PID control method in DC/DC Buck converter and SMC in DC/DC (Buck, and Buck Boost) converters. For the prototype, operational amplifiers (op-amps) are used to implement PID control in DC/DC Buck converter. For SMC op-amps are implemented in DC/DC Buck converter and dSPACETM is used to control the DC/DC Buck-Boost converter. The SMC can be applied to the DC/DC (Buck, Boost, and Buck-Boost) converters. A comparison of the effects of the PID control and the SMC on the DC/DC Buck converter response in steady state, under line variations, load variations, and different component variations is performed. Also the Conducted RF-Emissions between the PID and SMC DC/DC Buck Converter are compared. The thesis shows that, in comparison with the PID control, the SMC provides better steady-state response, better dynamic response, less EMI, inherent order reduction, robustness against system uncertainty disturbances, and an implicit stability proof. Giving a better steady-state and dynamic response, the SMC is implemented in a DC/DC resonant converter. The half-wave zero current switching (HWZCS) DC/DC Buck converter is selected as a converter topology. A general guideline to select the tank component values, needed for the designing of a HWZCS DC/DC Buck, is obtained. The implementation of the SMC to a HWZCS DC/DC Buck converter is analysed. The converter response is investigated in the steady-state region and in the dynamic region.

Validation study of the Spanish Version of the Work-Family Conflict Questionnaire (CCTF)

In this study, a brief Work-Family Conflict (WFC) Questionnaire in the Spanish language is proposed that takes into account the two directions commonly reported in the literature: work interference with family (WIF), and family interference with work (FIW). The results obtained through exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) with two independent samples, carried out for women and men, showed acceptable validity and reliability. A copy of the instrument in Spanish language is provided, together with the Amos 4 syntax to perform the factor invariance analysis for women and men. The suggested Work-Family Conflict Questionnaire (in Spanish, abbreviated as CCTF) may be useful in studies performed in the work setting, considering the special relevance of the concept in this line of research.

When cholesterol is not cholesterol: a note on the enzymatic determination of its concentration in model systems containing vegetable extracts

Background: Experimental evidences demonstrate that vegetable derived extracts inhibit cholesterol absorption in the gastrointestinal tract. To further explore the mechanisms behind, we modeled duodenal contents with several vegetable extracts. Results: By employing a widely used cholesterol quantification method based on a cholesterol oxidase-peroxidase coupled reaction we analyzed the effects on cholesterol partition. Evidenced interferences were analyzed by studying specific and unspecific inhibitors of cholesterol oxidase-peroxidase coupled reaction. Cholesterol was also quantified by LC/MS. We found a significant interference of diverse (cocoa and tea-derived) extracts over this method. The interference was strongly dependent on model matrix: while as in phosphate buffered saline, the development of unspecific fluorescence was inhibitable by catalase (but not by heat denaturation), suggesting vegetable extract derived H2O2 production, in bile-containing model systems, this interference also comprised cholesterol-oxidase inhibition. Several strategies, such as cholesterol standard addition and use of suitable blanks containing vegetable extracts were tested. When those failed, the use of a mass-spectrometry based chromatographic assay allowed quantification of cholesterol in models of duodenal contents in the presence of vegetable extracts. Conclusions: We propose that the use of cholesterol-oxidase and/or peroxidase based systems for cholesterol analyses in foodstuffs should be accurately monitored, as important interferences in all the components of the enzymatic chain were evident. The use of adequate controls, standard addition and finally, chromatographic analyses solve these issues.

La modificació del criteri d'adquisició de la personalitat civil: una anàlisi des del dret civil català

Malgrat que des de feia ja molt de temps existien raons socials, mediques i jurídiques més que suficients, han tingut de passar més de cent vint anys (1889-2011) per a que es dugués a terme la necessària reforma de l’obsolet article 30 CC. mitjançant la qual s’ha prescindit, per fi, de l’estranya, per anòmala, i criticada condicio iuris – figura humana i supervivència independent més enllà de les primeres 24 hores – que caracteritzava l’adquisició de la personalitat civil en el Dret espanyol, sense parangó en els ordenaments del seu entorn jurídic. El nou criteri, fonamentat únicament en el naixement entès des de la seva consideració jurídica – despreniment del claustre matern -, permet prescindir, des d’aquest “moment”, de qualsevol limitació a la projecció jurídica, tant personal com patrimonial, del nounat, incloent per tant els efectes successoris mortis causa. El desencadenant de la novetat legislativa, vehiculada per la nova Llei del Registre Civil (2011), no fou un altre que la regulació dispensada amb anterioritat (2010) per l’article 211-1.1 del Codi civil de Catalunya, que va fer descansar ja en el mer naixement l’atribució de la personalitat civil. Tant la tramitació parlamentària de la modificació de l’art. 30 CC. com el desenvolupament de la qüestió competencial plantejada pel Govern de l’Estat en contra del precepte català, confirmen, en un procés de mútua interferència, la influencia determinant que sobre la reforma duta a terme va tenir la decisió de Catalunya de legislar sobre aquesta matèria.

Anàlisi del recurs pilot "cases d'infants: nou paradigma d'atenció i tractament a la infància i l'adolescència".

El treball que es presenta a continuació és una recerca aplicada, consistent en l’anàlisi descriptiva d’una mostra d’infants i adolescents de 5 a 19 anys atesos al projecte “Cases d’Infants” des del desembre de 2010 fins al juliol de 2013. Aquesta investigació pretén donar a conèixer la nova perspectiva o paradigma d’atenció a la infància i l’adolescència a Catalunya que neix de la Llei dels Drets i les Oportunitats de la Infància i l’Adolescència (LDOIA, maig de 2010): basada en la prevenció, el model sistèmic i de complexitat, la col·laboració de la família com a element de canvi, el treball en xarxa i interprofessionalitat, la participació dels infants i adolescents, i la territorialitat, principalment. Un cop feta aquesta aproximació teòrica, s’ha concretat identificant aquesta nova perspectiva al projecte pilot “Cases d’Infants” (nascut al setembre de 2010), el qual desplega les actuacions que sorgeixen d’aquesta filosofia de treball i suport. Per a elaborar aquesta recerca s’ha emprat un disseny d’investigació no experimental descriptiu, on s’han associat i comparat variables per tal d’identificar interferències en les relacions –a través de proves estadístiques-, i proposar una certa tendència i pronòstic de les característiques del perfil atès al projecte i les interferències d’algunes variables amb el recurs final de l’infant o adolescent. Finalment, s’extreuen unes conclusions en relació a la bibliografia inicial i els resultats obtinguts en l’anàlisi de la mostra estudiada.

The planarian flatworm: an in vivo model for stem cell biology and nervous system regeneration

Planarian flatworms are an exception among bilaterians in that they possess a large pool of adult stem cells that enables them to promptly regenerate any part of their body, including the brain. Although known for two centuries for their remarkable regenerative capabilities, planarians have only recently emerged as an attractive model for studying regeneration and stem cell biology. This revival is due in part to the availability of a sequenced genome and the development of new technologies, such as RNA interference and next-generation sequencing, which facilitate studies of planarian regeneration at the molecular level. Here, we highlight why planarians are an exciting tool in the study of regeneration and its underlying stem cell biology in vivo, and discuss the potential promises and current limitations of this model organism for stem cell research and regenerative medicine.

Contribution of Intronic miR-338-3p and Its Hosting Gene AATK to Compensatory β-Cell Mass Expansion.

The elucidation of the mechanisms directing β-cell mass regeneration and maintenance is of interest, because the deficit of β-cell mass contributes to diabetes onset and progression. We previously found that the level of the microRNA (miRNA) miR-338-3p is decreased in pancreatic islets from rodent models displaying insulin resistance and compensatory β-cell mass expansion, including pregnant rats, diet-induced obese mice, and db/db mice. Transfection of rat islet cells with oligonucleotides that specifically block miR-338-3p activity increased the fraction of proliferating β-cells in vitro and promoted survival under proapoptotic conditions without affecting the capacity of β-cells to release insulin in response to glucose. Here, we evaluated the role of miR-338-3p in vivo by injecting mice with an adeno-associated viral vector permitting specific sequestration of this miRNA in β-cells. We found that the adeno-associated viral construct increased the fraction of proliferating β-cells confirming the data obtained in vitro. miR-338-3p is generated from an intron of the gene coding for apoptosis-associated tyrosine kinase (AATK). Similarly to miR-338-3p, we found that AATK is down-regulated in rat and human islets and INS832/13 β-cells in the presence of the cAMP-raising agents exendin-4, estradiol, and a G-protein-coupled Receptor 30 agonist. Moreover, AATK expression is reduced in islets of insulin resistant animal models and selective silencing of AATK in INS832/13 cells by RNA interference promoted β-cell proliferation. The results point to a coordinated reduction of miR-338-3p and AATK under insulin resistance conditions and provide evidence for a cooperative action of the miRNA and its hosting gene in compensatory β-cell mass expansion.