Science.gov

Sample records for linaire qui relie

  1. LinAir: A multi-element discrete vortex Weissinger aerodynamic prediction method

    NASA Technical Reports Server (NTRS)

    Durston, Donald A.

    1993-01-01

    LinAir is a vortex lattice aerodynamic prediction method similar to Weissinger's extended lifting-line theory, except that the circulation around a wing is represented by discrete horseshoe vortices, not a continuous distribution of vorticity. The program calculates subsonic longitudinal and lateral/directional aerodynamic forces and moments for arbitrary aircraft geometries. It was originally written by Dr. Ilan Kroo of Stanford University, and subsequently modified by the author to simplify modeling of complex configurations. The Polhamus leading-edge suction analogy was added by the author to extend the range of applicability of LinAir to low aspect ratio (i.e., fighter-type) configurations. A brief discussion of the theory of LinAir is presented, and details on how to run the program are given along with some comparisons with experimental data to validate the code. Example input and output files are given in the appendices to aid in understanding the program and its use. This version of LinAir runs in the VAX/VMS, Cray UNICOS, and Silicon Graphics Iris workstation environments at the time of this writing.

  2. Lying relies on the truth.

    PubMed

    Debey, Evelyne; De Houwer, Jan; Verschuere, Bruno

    2014-09-01

    Cognitive models of deception focus on the conflict-inducing nature of the truth activation during lying. Here we tested the counterintuitive hypothesis that the truth can also serve a functional role in the act of lying. More specifically, we examined whether the construction of a lie can involve a two-step process, where the first step entails activating the truth, based upon which a lie response can be formulated in a second step. To investigate this hypothesis, we tried to capture the covert truth activation in a reaction-time based deception paradigm. Together with each question, we presented either the truth or lie response as distractors. If lying depends on the covert activation of the truth, deceptive responses would thus be facilitated by truth distractors relative to lie distractors. Our results indeed revealed such a "covert congruency" effect, both in errors and reaction times (Experiment 1). Moreover, stimulating participants to use the distractor information by increasing the proportion of truth distractor trials enlarged the "covert congruency" effects, and as such confirmed that the effects operate at a covert response level (Experiment 2). Our findings lend support to the idea that lying relies on a first step of truth telling, and call for a shift in theoretical thinking that highlights both the functional and interfering properties of the truth activation in the lying process.

  3. Maladies reliées aux loisirs aquatiques

    PubMed Central

    Sanborn, Margaret; Takaro, Tim

    2013-01-01

    Résumé Objectif Passer en revue les facteurs de risque, la prise en charge et la prévention des maladies reliées aux loisirs aquatiques en pratique familiale. Sources des données Des articles originaux et de synthèse entre janvier 1998 et février 2012 ont été identifiés à l’aide de PubMed et des expressions de recherche en anglais water-related illness, recreational water illness et swimmer illness. Message principal Il y a un risque de 3 % à 8 % de maladies gastrointestinales (MGI) après la baignade. Les groupes à risque élevé de MGI sont les enfants de moins de 5 ans, surtout s’ils n’ont pas été vaccinés contre le rotavirus, les personnes âgées et les patients immunodéficients. Les enfants sont à plus grand risque parce qu’ils avalent plus d’eau quand ils nagent, restent dans l’eau plus longtemps et jouent dans l’eau peu profonde et le sable qui sont plus contaminés. Les adeptes des sports dans lesquels le contact avec l’eau est abondant comme le triathlon et le surf cerf-volant sont aussi à risque élevé et même ceux qui s’adonnent à des activités impliquant un contact partiel avec l’eau comme la navigation de plaisance et la pêche ont un risque de 40 % à 50 % fois plus grand de MGI par rapport à ceux qui ne pratiquent pas de sports aquatiques. Il y a lieu de faire une culture des selles quand on soupçonne une maladie reliée aux loisirs aquatiques et l’échelle clinique de la déshydratation est utile pour l’évaluation des besoins de traitement chez les enfants affectés. Conclusion Les maladies reliées aux loisirs aquatiques est la principale cause de MGI durant la saison des baignades. La reconnaissance que la baignade est une source importante de maladies peut aider à prévenir les cas récurrents et secondaires. On recommande fortement le vaccin contre le rotavirus chez les enfants qui se baignent souvent.

  4. Brain Relies on Two Timekeepers for Sleep

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160407.html Brain Relies on Two Timekeepers for Sleep Study shows ... internal "hourglass" affect how different parts of your brain respond to sleep deprivation, a new study shows. ...

  5. Recent results for the Raytheon RELI program

    NASA Astrophysics Data System (ADS)

    Filgas, David; Clatterbuck, Todd; Cashen, Matt; Daniele, Andrew; Hughes, Steve; Mordaunt, David

    2012-06-01

    We describe our approach and latest results for Raytheon's RELI (Robust Electric Laser Initiative) program. Our architecture leverages a slab-based, Master Oscillator / Power Amplifier (MOPA) architecture based on Raytheon's unique planar waveguide amplifier. Technical objectives for this effort are to demonstrate > 25 kW output with excellent beam quality and an electrical to optical efficiency > 30%. The planar waveguide architecture provides compact packaging and is inherently scalable to 100 kW or greater in a single beam line. We report on the latest progress and test results for the program.

  6. Nombre de valeurs polynomiales qui divisent un entier

    NASA Astrophysics Data System (ADS)

    de La Bretèche, R.

    2001-09-01

    Soit P un polynôme à coefficients entiers de degré 2 et [Delta] son discriminant. La quantité [tau]P(n), définie par [tau]P(n) := card {P(m) > 0: P(m)[mid R:]n, m [set membership] [open face Z]}, compte le nombre de diviseurs d de n qui s'écrivent sous la forme d = P(m). Lorsque P(X) = X(X + 1), le cardinal [tau]X(X+1)(n) est égal au nombre de diviseurs consécutifs de n.

  7. Rely and Toxic Shock Syndrome: A Technological Health Crisis

    PubMed Central

    Vostral, Sharra L.

    2011-01-01

    This essay examines factors leading to the identification of Toxic Shock Syndrome with the bacteria Staphylococcus aureus in 1978 and the specific role of Rely tampons in generating a technologically rooted health crisis. The concept biologically incompatible technology is offered to explain the relationship between constituent bacteria, women’s menstrual cycles, and a reactive technology that converged to create the ideal environment for the S. aureus bacteria to live and flourish in some women. The complicated and reactive relationship of the Rely tampon to emergent disease, corporate interests, public health, and injury law reveals the dangers of naturalizing technologies. PMID:22180682

  8. Rely and Toxic Shock Syndrome: a technological health crisis.

    PubMed

    Vostral, Sharra L

    2011-12-01

    This essay examines factors leading to the identification of Toxic Shock Syndrome with the bacteria Staphylococcus aureus in 1978 and the specific role of Rely tampons in generating a technologically rooted health crisis. The concept biologically incompatible technology is offered to explain the relationship between constituent bacteria, women's menstrual cycles, and a reactive technology that converged to create the ideal environment for the S. aureus bacteria to live and flourish in some women. The complicated and reactive relationship of the Rely tampon to emergent disease, corporate interests, public health, and injury law reveals the dangers of naturalizing technologies.

  9. Covert face recognition relies on affective valence in congenital prosopagnosia.

    PubMed

    Bate, Sarah; Haslam, Catherine; Jansari, Ashok; Hodgson, Timothy L

    2009-06-01

    Dominant accounts of covert recognition in prosopagnosia assume subthreshold activation of face representations created prior to onset of the disorder. Yet, such accounts cannot explain covert recognition in congenital prosopagnosia, where the impairment is present from birth. Alternatively, covert recognition may rely on affective valence, yet no study has explored this possibility. The current study addressed this issue in 3 individuals with congenital prosopagnosia, using measures of the scanpath to indicate recognition. Participants were asked to memorize 30 faces paired with descriptions of aggressive, nice, or neutral behaviours. In a later recognition test, eye movements were monitored while participants discriminated studied from novel faces. Sampling was reduced for studied--nice compared to studied--aggressive faces, and performance for studied--neutral and novel faces fell between these two conditions. This pattern of findings suggests that (a) positive emotion can facilitate processing in prosopagnosia, and (b) covert recognition may rely on emotional valence rather than familiarity.

  10. rely.py, a python script to detect reliable clades.

    PubMed

    Li, Blaise; Dettai, Agnès; Lecointre, Guillaume

    2010-01-01

    rely.py is a program implementing the method to detect independently repeated clades by comparing phylogenies as described in Li and Lecointre (2009) and adapted to incompletely overlapping datasets in Li et al. (2009). The comparison can be performed on trees obtained by any inference method (maximum parsimony, Bayesian inference, maximum likelihood). The program computes repetition indices, provides greedy summary trees for each validity domain and a nexus matrix representation of the clades weighted by their repetition indices. The additional script concatnexus.py assists the user in preparing the primary analyses, but it can also be used separately to concatenate nexus datasets.

  11. Robust Sensing of Approaching Vehicles Relying on Acoustic Cues

    PubMed Central

    Mizumachi, Mitsunori; Kaminuma, Atsunobu; Ono, Nobutaka; Ando, Shigeru

    2014-01-01

    The latest developments in automobile design have allowed them to be equipped with various sensing devices. Multiple sensors such as cameras and radar systems can be simultaneously used for active safety systems in order to overcome blind spots of individual sensors. This paper proposes a novel sensing technique for catching up and tracking an approaching vehicle relying on an acoustic cue. First, it is necessary to extract a robust spatial feature from noisy acoustical observations. In this paper, the spatio-temporal gradient method is employed for the feature extraction. Then, the spatial feature is filtered out through sequential state estimation. A particle filter is employed to cope with a highly non-linear problem. Feasibility of the proposed method has been confirmed with real acoustical observations, which are obtained by microphones outside a cruising vehicle. PMID:24887038

  12. Human children rely more on social information than chimpanzees do

    PubMed Central

    van Leeuwen, Edwin J. C.; Call, Josep; Haun, Daniel B. M.

    2014-01-01

    Human societies are characterized by more cultural diversity than chimpanzee communities. However, it is currently unclear what mechanism might be driving this difference. Because reliance on social information is a pivotal characteristic of culture, we investigated individual and social information reliance in children and chimpanzees. We repeatedly presented subjects with a reward-retrieval task on which they had collected conflicting individual and social information of equal accuracy in counterbalanced order. While both species relied mostly on their individual information, children but not chimpanzees searched for the reward at the socially demonstrated location more than at a random location. Moreover, only children used social information adaptively when individual knowledge on the location of the reward had not yet been obtained. Social information usage determines information transmission and in conjunction with mechanisms that create cultural variants, such as innovation, it facilitates diversity. Our results may help explain why humans are more culturally diversified than chimpanzees. PMID:25392309

  13. In Vitro Biosynthesis and Chemical Identification of UDP-N-acetyl-d-quinovosamine (UDP-d-QuiNAc)*

    PubMed Central

    Li, Tiezheng; Simonds, Laurie; Kovrigin, Evgenii L.; Noel, K. Dale

    2014-01-01

    N-acetyl-d-quinovosamine (2-acetamido-2,6-dideoxy-d-glucose, QuiNAc) occurs in the polysaccharide structures of many Gram-negative bacteria. In the biosynthesis of QuiNAc-containing polysaccharides, UDP-QuiNAc is the hypothetical donor of the QuiNAc residue. Biosynthesis of UDP-QuiNAc has been proposed to occur by 4,6-dehydration of UDP-N-acetyl-d-glucosamine (UDP-GlcNAc) to UDP-2-acetamido-2,6-dideoxy-d-xylo-4-hexulose followed by reduction of this 4-keto intermediate to UDP-QuiNAc. Several specific dehydratases are known to catalyze the first proposed step. A specific reductase for the last step has not been demonstrated in vitro, but previous mutant analysis suggested that Rhizobium etli gene wreQ might encode this reductase. Therefore, this gene was cloned and expressed in Escherichia coli, and the resulting His6-tagged WreQ protein was purified. It was tested for 4-reductase activity by adding it and NAD(P)H to reaction mixtures in which 4,6-dehydratase WbpM had acted on the precursor substrate UDP-GlcNAc. Thin layer chromatography of the nucleotide sugars in the mixture at various stages of the reaction showed that WbpM converted UDP-GlcNAc completely to what was shown to be its 4-keto-6-deoxy derivative by NMR and that addition of WreQ and NADH led to formation of a third compound. Combined gas chromatography-mass spectrometry analysis of acid hydrolysates of the final reaction mixture showed that a quinovosamine moiety had been synthesized after WreQ addition. The two-step reaction progress also was monitored in real time by NMR. The final UDP-sugar product after WreQ addition was purified and determined to be UDP-d-QuiNAc by one-dimensional and two-dimensional NMR experiments. These results confirmed that WreQ has UDP-2-acetamido-2,6-dideoxy-d-xylo-4-hexulose 4-reductase activity, completing a pathway for UDP-d-QuiNAc synthesis in vitro. PMID:24817117

  14. 47 CFR 15.717 - TVBDs that rely on spectrum sensing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false TVBDs that rely on spectrum sensing. 15.717... Television Band Devices § 15.717 TVBDs that rely on spectrum sensing. (a) Applications for certification. Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing...

  15. 47 CFR 15.717 - TVBDs that rely on spectrum sensing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false TVBDs that rely on spectrum sensing. 15.717... Television Band Devices § 15.717 TVBDs that rely on spectrum sensing. (a) Applications for certification. Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing...

  16. 47 CFR 15.717 - TVBDs that rely on spectrum sensing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false TVBDs that rely on spectrum sensing. 15.717... Television Band Devices § 15.717 TVBDs that rely on spectrum sensing. (a) Applications for certification. Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing...

  17. 47 CFR 15.717 - TVBDs that rely on spectrum sensing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Television Band Devices § 15.717 TVBDs that rely on spectrum sensing. (a) Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing to identify available channels. Devices authorized... 47 Telecommunication 1 2010-10-01 2010-10-01 false TVBDs that rely on spectrum sensing....

  18. 47 CFR 15.717 - TVBDs that rely on spectrum sensing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Television Band Devices § 15.717 TVBDs that rely on spectrum sensing. (a) Applications for certification. Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing to... 47 Telecommunication 1 2012-10-01 2012-10-01 false TVBDs that rely on spectrum sensing....

  19. Control of human African trypanosomiasis in the Quiçama focus, Angola.

    PubMed Central

    Ruiz, José Antonio; Simarro, Pere P.; Josenando, Teofilo

    2002-01-01

    OBJECTIVE: To update the epidemiological status of human African trypanosomiasis (HAT), also known as sleeping sickness, in the Quiçama focus, province of Bengo, Angola, and to establish a HAT control programme. METHODS: In 1997, 8796 people (the population of 31 villages) were serologically screened for Trypanosoma brucei gambiense, the causative agent of HAT. In 1998 and 1999, surveys were carried out in villages where HAT cases had been identified in 1997. Individuals were screened using the card agglutination trypanosomiasis test (CATT), and then examined for the presence of the parasite. CATT- positive individuals in whom the presence of the parasite could not be confirmed were further tested with the CATT using serum dilutions, and those with a positive antibody end titre of 1-in-4 or above were followed-up. Patients with < or =10 white cells/micro l and no trypanosomes in their cerebrospinal fluid (CSF) were classified as being in the first stage of the disease. Vector control was not considered necessary or feasible. FINDINGS: The main transmission areas were on the Kwanza riverbanks, where 5042 inhabitants live. In 1997, the HAT prevalence was 1.97%, but this decreased to 0.55% in 1998 and to 0.33% in 1999. The relapse rate was 3% in patients treated with pentamidine and 3.5% in patients treated with melarsoprol. In patients treated with pentamidine, there was no difference in the relapse rate for patients with initial CSF white cell counts of 0-5 cells/ micro l or 6-10 cells/micro l. The overall mortality rate was 0.6% and the rate of reactive arsenical encephalopathy among the melarsoprol-treated patients was 1.7%. CONCLUSION: The epidemiological status of the disease was updated and the transmission areas were defined. The control methods implemented allowed the disease prevalence to be reduced. PMID:12378293

  20. Overstepping the garnet isograd: a comparison of QuiG barometry and thermodynamic modeling

    NASA Astrophysics Data System (ADS)

    Spear, Frank S.; Thomas, Jay B.; Hallett, Benjamin W.

    2014-09-01

    The consequences of overstepping the garnet isograd reaction have been investigated by comparing the composition of garnet formed at overstepped P-T conditions (the overstep or "OS" model) with the P-T conditions that would be inferred by assuming garnet nucleated in equilibrium with the matrix assemblage at the isograd (the equilibrium or "EQ" model). The garnet nucleus composition formed at overstepped conditions is calculated as the composition that produces the maximum decrease in Gibbs free energy from the equilibrated, garnet-absent, matrix assemblage for the bulk composition under study. Isopleths were then calculated for this garnet nucleus composition assuming equilibrium with the matrix assemblage (the EQ model). Comparison of the actual P-T conditions of nucleation (the OS model) with those inferred from the EQ model reveals considerable discrepancy between the two. In general, the inferred garnet nucleation P-T conditions (the EQ model) are at a lower temperature and higher or lower pressure (depending on the coexisting calcic phase(s)) than the actual (OS model) nucleation conditions. Moreover, the degree of discrepancy increases with the degree of overstepping. Independent estimates of the pressure of nucleation of garnet were made using the Raman shift of quartz inclusions in garnet (quartz-in-garnet or QuiG barometry). To test the validity of this method, an experimental synthesis of garnet containing quartz inclusions was made at 800 °C, 20 kbar, and the measured Raman shift reproduced the synthesis conditions to within 120 bars. Raman band shifts from three natural samples were then used to calculate an isochore along which garnet was presumed to have nucleated. Model calculations were made at several temperatures along this isochore (the OS model), and these P-T conditions were compared to those computed assuming equilibrium nucleation (the EQ model) to estimate the degree of overstepping displayed by these samples. A sample from the garnet

  1. 77 FR 70117 - Purchase of Certain Debt Securities by Business and Industrial Development Companies Relying on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-23

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE... Development Companies Relying on an Investment Company Act Exemption AGENCY: Securities and Exchange... standard of credit quality that must be met by certain debt securities purchased by entities relying on...

  2. The thirty gigahertz instrument receiver for the Q-U-I Joint Tenerife experiment: concept and experimental results.

    PubMed

    Villa, Enrique; Cano, Juan L; Cagigas, Jaime; Ortiz, David; Casas, Francisco J; Pérez, Ana R; Aja, Beatriz; Terán, J Vicente; de la Fuente, Luisa; Artal, Eduardo; Hoyland, Roger; Mediavilla, Ángel

    2015-02-01

    This paper presents the analysis, design, and characterization of the thirty gigahertz instrument receiver developed for the Q-U-I Joint Tenerife experiment. The receiver is aimed to obtain polarization data of the cosmic microwave background radiation from the sky, obtaining the Q, U, and I Stokes parameters of the incoming signal simultaneously. A comprehensive analysis of the theory behind the proposed receiver is presented for a linearly polarized input signal, and the functionality tests have demonstrated adequate results in terms of Stokes parameters, which validate the concept of the receiver based on electronic phase switching.

  3. The thirty gigahertz instrument receiver for the Q-U-I Joint Tenerife experiment: Concept and experimental results

    SciTech Connect

    Villa, Enrique Cano, Juan L.; Cagigas, Jaime; Pérez, Ana R.; Aja, Beatriz; Terán, J. Vicente; Fuente, Luisa de la; Artal, Eduardo; Mediavilla, Ángel

    2015-02-15

    This paper presents the analysis, design, and characterization of the thirty gigahertz instrument receiver developed for the Q-U-I Joint Tenerife experiment. The receiver is aimed to obtain polarization data of the cosmic microwave background radiation from the sky, obtaining the Q, U, and I Stokes parameters of the incoming signal simultaneously. A comprehensive analysis of the theory behind the proposed receiver is presented for a linearly polarized input signal, and the functionality tests have demonstrated adequate results in terms of Stokes parameters, which validate the concept of the receiver based on electronic phase switching.

  4. DISCOURS QUI RÉSISTENT À L’OBJECTIVATION : QUE PEUT-ON EN TIRER POUR L’ÉVALUATION?

    PubMed Central

    Brousselle, Astrid

    2013-01-01

    Résumé L’évaluateur doit porter attention aux distorsions qu’il contribue à créer lorsqu’il utilise l’entrevue comme méthode de collecte de données. L’évaluation est un exercice politique qui, placé dans un contexte politique, peut favoriser l’émergence de discours de résistance à l’objectivation. À partir des entrevues que nous avons effectuées lors de l’évaluation du processus d’implantation de l’initiative ONUSIDA d’accès aux médicaments au Chili, nous illustrons différentes tactiques que les acteurs utilisent et qui peuvent soit attirer la sympathie de l’évaluateur, soit faire obstacle à son besoin d’information. Nous présentons une méthode d’analyse que l’évaluateur peut utiliser pour redonner du sens aux discours de résistance. PMID:23997421

  5. Does stimulus complexity determine whether working memory storage relies on prefrontal or sensory cortex?

    PubMed

    Bancroft, Tyler D; Hockley, William E; Servos, Philip

    2014-10-01

    Traditionally, working and short-term memory (WM/STM) have been believed to rely on storage systems located in prefrontal cortex (PFC). However, recent experimental and theoretical efforts have suggested that, in many cases, sensory or other task-relevant cortex is the actual storage substrate for WM/STM. What factors determine whether a given WM/STM task relies on PFC or sensory cortex? In the present article, we outline recent experimental findings and suggest that the dimensionality or complexity of the to-be-remembered property or properties of a stimulus can be a determining factor.

  6. Physical characteristics of stream subbasins in the Lac qui Parle River basin, southwestern Minnesota and eastern South Dakota

    USGS Publications Warehouse

    Lorenz, D.L.; Sanocki, C.A.; Winterstein, Thomas A.

    1994-01-01

    Data describing the physical characteristics of stream subbasins upstream from selected points on streams in the Lac qui Parle River basin, located in southwestern Minnesota and eastern South Dakota, are presented in this report. The physical charac- teristics are the drainage area of the subbasin, the percentage area of the subbasin covered only by lakes, the percentage area of the subbasin covered by both lakes and wetlands, the main-channel length. and the main-channel slope. The points on the stream include outlets of subbasins of at least 5 square miles, outfalls of sewage treatment plants, and locations of U.S. Geological Survey low-flow, high-flow, and continuous-record gaging stations.

  7. 77 FR 39561 - Advanced Braking Technologies That Rely on Forward-Looking Sensors; Request for Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ... Sensors; Request for Comments AGENCY: National Highway Traffic Safety Administration (NHTSA), Department... technologies that rely on forward-looking sensors to supplement driver braking or to actuate automatic braking... information from forward-looking sensors, usually a camera or radar, to determine whether or not a crash...

  8. Bidirectional Regulation of Innate and Learned Behaviors That Rely on Frequency Discrimination by Cortical Inhibitory Neurons.

    PubMed

    Aizenberg, Mark; Mwilambwe-Tshilobo, Laetitia; Briguglio, John J; Natan, Ryan G; Geffen, Maria N

    2015-12-01

    The ability to discriminate tones of different frequencies is fundamentally important for everyday hearing. While neurons in the primary auditory cortex (AC) respond differentially to tones of different frequencies, whether and how AC regulates auditory behaviors that rely on frequency discrimination remains poorly understood. Here, we find that the level of activity of inhibitory neurons in AC controls frequency specificity in innate and learned auditory behaviors that rely on frequency discrimination. Photoactivation of parvalbumin-positive interneurons (PVs) improved the ability of the mouse to detect a shift in tone frequency, whereas photosuppression of PVs impaired the performance. Furthermore, photosuppression of PVs during discriminative auditory fear conditioning increased generalization of conditioned response across tone frequencies, whereas PV photoactivation preserved normal specificity of learning. The observed changes in behavioral performance were correlated with bidirectional changes in the magnitude of tone-evoked responses, consistent with predictions of a model of a coupled excitatory-inhibitory cortical network. Direct photoactivation of excitatory neurons, which did not change tone-evoked response magnitude, did not affect behavioral performance in either task. Our results identify a new function for inhibition in the auditory cortex, demonstrating that it can improve or impair acuity of innate and learned auditory behaviors that rely on frequency discrimination. PMID:26629746

  9. Liberals and conservatives rely on common moral foundations when making moral judgments about influential people.

    PubMed

    Frimer, Jeremy A; Biesanz, Jeremy C; Walker, Lawrence J; MacKinlay, Callan W

    2013-06-01

    Do liberals and conservatives have qualitatively different moral points of view? Specifically, do liberals and conservatives rely on the same or different sets of moral foundations-care, fairness, loyalty, authority, and purity (Haidt, 2012)-when making moral judgments about influential people? In Study 1, 100 experts evaluated the impact that 40 influential figures had on each moral foundation, yielding stimulus materials for the remaining studies. In Study 2, 177 American liberal and conservative professors rated the moral character of the same figures. Liberals and conservatives relied on the same 3 moral foundations: For both groups, promoting care, fairness, and purity-but not authority or loyalty-predicted moral judgments of the targets. For liberals, promoting authority negatively predicted moral judgments. Political ideology moderated the purity-moral and especially authority-moral relationships, implying that purity and authority are grounds for political disagreement. Study 3 replicated these results with 222 folk raters. Folk liberals and conservatives disagreed even less about the moral standing of the targets than did experts. Together, these findings imply that moral foundation theory may have exaggerated differences between liberals and conservatives. The moral codes of liberals and conservatives do differ systematically; however, their similarities outweigh their differences. Liberals and conservatives alike rely on care, fairness, and purity when making moral judgments about influential people. PMID:23586414

  10. 40 CFR 26.1706 - Criteria and procedure for decisions to protect public health by relying on otherwise...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Assessing Whether To Rely on the Results of Human Research in EPA Actions § 26.1706 Criteria and procedure for decisions to protect public health by relying on otherwise unacceptable research. This section... protect public health by relying on otherwise unacceptable research. 26.1706 Section 26.1706 Protection...

  11. Poison frogs rely on experience to find the way home in the rainforest.

    PubMed

    Pašukonis, Andrius; Warrington, Ian; Ringler, Max; Hödl, Walter

    2014-11-01

    Among vertebrates, comparable spatial learning abilities have been found in birds, mammals, turtles and fishes, but virtually nothing is known about such abilities in amphibians. Overall, amphibians are the most sedentary vertebrates, but poison frogs (Dendrobatidae) routinely shuttle tadpoles from terrestrial territories to dispersed aquatic deposition sites. We hypothesize that dendrobatid frogs rely on learning for flexible navigation. We tested the role of experience with the local cues for poison frog way-finding by (i) experimentally displacing territorial males of Allobates femoralis over several hundred metres, (ii) using a harmonic direction finder with miniature transponders to track these small frogs, and (iii) using a natural river barrier to separate the translocated frogs from any familiar landmarks. We found that homeward orientation was disrupted by the translocation to the unfamiliar area but frogs translocated over similar distances in their local area showed significant homeward orientation and returned to their territories via a direct path. We suggest that poison frogs rely on spatial learning for way-finding in their local area. PMID:25411379

  12. Poison frogs rely on experience to find the way home in the rainforest.

    PubMed

    Pašukonis, Andrius; Warrington, Ian; Ringler, Max; Hödl, Walter

    2014-11-01

    Among vertebrates, comparable spatial learning abilities have been found in birds, mammals, turtles and fishes, but virtually nothing is known about such abilities in amphibians. Overall, amphibians are the most sedentary vertebrates, but poison frogs (Dendrobatidae) routinely shuttle tadpoles from terrestrial territories to dispersed aquatic deposition sites. We hypothesize that dendrobatid frogs rely on learning for flexible navigation. We tested the role of experience with the local cues for poison frog way-finding by (i) experimentally displacing territorial males of Allobates femoralis over several hundred metres, (ii) using a harmonic direction finder with miniature transponders to track these small frogs, and (iii) using a natural river barrier to separate the translocated frogs from any familiar landmarks. We found that homeward orientation was disrupted by the translocation to the unfamiliar area but frogs translocated over similar distances in their local area showed significant homeward orientation and returned to their territories via a direct path. We suggest that poison frogs rely on spatial learning for way-finding in their local area.

  13. The Effect of Instruction on Children's Perceived Musical Tension in Debussy's "Noel des enfants qui n'ont plus de maisons"

    ERIC Educational Resources Information Center

    Hackworth, Rhonda S.; Fredrickson, William E.

    2012-01-01

    The study explored possible effects of instruction (highlighting a choral composition's historical and social context) on perceived musical tension recorded by children (N = 62). Children listened to a recording of Debussy's "Noel des enfants qui n'ont plus de maisons" (The Christmas Carol of the Children who No Longer Have a House/Home) performed…

  14. Improving web access for individuals who rely on augmentative and alternative communication.

    PubMed

    Bryen, Diane Nelson; Heake, George; Semenuk, Amy; Segal, Mary

    2010-03-01

    People with significant speech and motor disabilities often face obstacles attempting to navigate the World Wide Web. This is especially true for the millions of children and adults worldwide who rely on or could benefit from augmentative and alternative communication (AAC). This study was designed to test the usability of WebAACcess, an accessibility enhancement tool designed to bypass some of the barriers to navigating the web. Using a repeated-measures research design, whereby subjects were their own controls, each of the 12 participants (7 with motor disabilities who used AAC and 5 peers without disabilities) navigated equivalent web pages using Internet Explorer alone and Internet Explorer with WebAACcess. Results consistently demonstrated that navigating using WebAACess with Internet Explorer was more efficient, easier, and equally effective for all of the participants than navigating with Internet Explorer alone.

  15. Do conscious perception and unconscious processing rely on independent mechanisms? A meta-contrast study.

    PubMed

    Peremen, Ziv; Lamy, Dominique

    2014-02-01

    There is currently no consensus regarding what measures are most valid to demonstrate perceptual processing without awareness. Likewise, whether conscious perception and unconscious processing rely on independent mechanisms or lie on a continuum remains a matter of debate. Here, we addressed these issues by comparing the time courses of subjective reports, objective discrimination performance and response priming during meta-contrast masking, under similar attentional demands. We found these to be strikingly similar, suggesting that conscious perception and unconscious processing cannot be dissociated by their time course. Our results also demonstrate that unconscious processing, indexed by response priming, occurs, and that objective discrimination performance indexes the same conscious processes as subjective visibility reports. Finally, our results underscore the role of attention by showing that how much attention the stimulus receives relative to the mask, rather than whether processing is measured by conscious discrimination or by priming, determines the time course of meta-contrast masking. PMID:24398259

  16. Copy-when-uncertain: bumblebees rely on social information when rewards are highly variable

    PubMed Central

    Alem, Sylvain; Chittka, Lars; Shultz, Susanne

    2016-01-01

    To understand the relative benefits of social and personal information use in foraging decisions, we developed an agent-based model of social learning that predicts social information should be more adaptive where resources are highly variable and personal information where resources vary little. We tested our predictions with bumblebees and found that foragers relied more on social information when resources were variable than when they were not. We then investigated whether socially salient cues are used preferentially over non-social ones in variable environments. Although bees clearly used social cues in highly variable environments, under the same conditions they did not use non-social cues. These results suggest that bumblebees use a ‘copy-when-uncertain’ strategy. PMID:27303053

  17. Pathfinding of corticothalamic axons relies on a rendezvous with thalamic projections.

    PubMed

    Deck, Marie; Lokmane, Ludmilla; Chauvet, Sophie; Mailhes, Caroline; Keita, Maryama; Niquille, Mathieu; Yoshida, Michio; Yoshida, Yutaka; Lebrand, Cécile; Mann, Fanny; Grove, Elizabeth A; Garel, Sonia

    2013-02-01

    Major outputs of the neocortex are conveyed by corticothalamic axons (CTAs), which form reciprocal connections with thalamocortical axons, and corticosubcerebral axons (CSAs) headed to more caudal parts of the nervous system. Previous findings establish that transcriptional programs define cortical neuron identity and suggest that CTAs and thalamic axons may guide each other, but the mechanisms governing CTA versus CSA pathfinding remain elusive. Here, we show that thalamocortical axons are required to guide pioneer CTAs away from a default CSA-like trajectory. This process relies on a hold in the progression of cortical axons, or waiting period, during which thalamic projections navigate toward cortical axons. At the molecular level, Sema3E/PlexinD1 signaling in pioneer cortical neurons mediates a "waiting signal" required to orchestrate the mandatory meeting with reciprocal thalamic axons. Our study reveals that temporal control of axonal progression contributes to spatial pathfinding of cortical projections and opens perspectives on brain wiring. PMID:23395374

  18. Hummingbirds rely on both paracellular and carrier-mediated intestinal glucose absorption to fuel high metabolism.

    PubMed

    McWhorter, Todd J; Bakken, Bradley Hartman; Karasov, William H; del Rio, Carlos Martínez

    2006-03-22

    Twenty years ago, the highest active glucose transport rate and lowest passive glucose permeability in vertebrates were reported in Rufous and Anna's hummingbirds (Selasphorus rufus, Calypte anna). These first measurements of intestinal nutrient absorption in nectarivores provided an unprecedented physiological foundation for understanding their foraging ecology. They showed that physiological processes are determinants of feeding behaviour. The conclusion that active, mediated transport accounts for essentially all glucose absorption in hummingbirds influenced two decades of subsequent research on the digestive physiology and nutritional ecology of nectarivores. Here, we report new findings demonstrating that the passive permeability of hummingbird intestines to glucose is much higher than previously reported, suggesting that not all sugar uptake is mediated. Even while possessing the highest active glucose transport rates measured in vertebrates, hummingbirds must rely partially on passive non-mediated intestinal nutrient absorption to meet their high mass-specific metabolic demands.

  19. RELY: A reliability modeling system for analysis of sodium-sulfur battery configurations

    SciTech Connect

    Hostick, C.J.; Huber, H.D.; Doggett, W.H.; Dirks, J.A.; Dovey, J.F.; Grinde, R.B.; Littlefield, J.S.; Cuta, F.M.

    1987-06-01

    In support of the Office of Energy Storage and Distribution of the US Department of Energy (DOE), Pacific Northwest Laboratory has produced a microcomputer-based software package, called RELY, to assess the impact of sodium-sulfur cell reliability on constant current discharge battery performance. The Fortran-based software operates on IBM microcomputers and IBM-compatibles that have a minimum of 512K of internal memory. The software package has three models that provide the following: (1) a description of the failure distribution parameters used to model cell failure, (2) a Monte Carlo simulation of battery life, and (3) a detailed discharge model for a user-specified battery discharge cycle. 6 refs., 31 figs., 4 tabs.

  20. Study: To minimize errors, rely on interpreters when caring for LEP patients in the ED.

    PubMed

    2012-08-01

    A new study strongly suggests that it is important for EDs to rely on professional interpreters, rather than ad hoc interpreters or no interpreters at all, when caring for patients with limited English proficiency (LEP). The researchers examined health care encounters involving LEP patients at two pediatric EDs, and found that the encounters associated with professional interpreters were associated with far fewer errors of potential clinical consequence than the encounters associated with ad hoc interpreters or no interpreters. Experts say the most important first step in minimizing language-based errors is to identify patients with LEP when they present for care. Professional interpreters are defined as having at least 100 hours of training. Researchers say that when evaluating interpreters, professional training is more valuable in terms of minimizing errors than experience on the job. Make sure that interpreters are available to LEP patients throughout the course of their ED visit as well as during any follow-up visits or telephone calls.

  1. Collective mesendoderm migration relies on an intrinsic directionality signal transmitted through cell contacts.

    PubMed

    Dumortier, Julien G; Martin, Sandro; Meyer, Dirk; Rosa, Frederic M; David, Nicolas B

    2012-10-16

    Collective cell migration is key to morphogenesis, wound healing, or cancer cell migration. However, its cellular bases are just starting to be unraveled. During vertebrate gastrulation, axial mesendoderm migrates in a group, the prechordal plate, from the embryonic organizer to the animal pole. How this collective migration is achieved remains unclear. Previous work has suggested that cells migrate as individuals, with collective movement resulting from the addition of similar individual cell behavior. Through extensive analyses of cell trajectories, morphologies, and polarization in zebrafish embryos, we reveal that all prechordal plate cells show the same behavior and rely on the same signaling pathway to migrate, as expected if they do so individually. However, by using cell transplants, we demonstrate that prechordal plate migration is a true collective process, as isolated cells do not migrate toward the animal pole. They are still polarized and motile but lose directionality. Directionality is restored upon contact with the endogenous prechordal plate. This contact dependent orientation relies on E-cadherin, Wnt-PCP signaling, and Rac1. Importantly, groups of cells also need contact with the endogenous plate to orient correctly, showing an instructive role of the plate in establishing directionality. Overall, our results lead to an original model of collective migration in which directional information is contained within the moving group rather than provided by extrinsic cues, and constantly maintained in cells by contacts with their neighbors. This self-organizing model could account for collective invasion of new territories, as observed in cancer strands, without requirement for any attractant in the colonized tissue.

  2. 16 CFR 1502.25 - Disclosure of data and information to be relied on by the participants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Disclosure of data and information to be... Hearing Procedures § 1502.25 Disclosure of data and information to be relied on by the participants. (a... hearing are not required to be submitted. (2) All other documentary data and information relied upon....

  3. 40 CFR 26.1706 - Criteria and procedure for decisions to protect public health by relying on otherwise...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... protect public health by relying on otherwise unacceptable research. 26.1706 Section 26.1706 Protection of... for decisions to protect public health by relying on otherwise unacceptable research. This section... would impose a more stringent regulatory restriction that would improve protection of public...

  4. Defining the buffering process by a triprotic acid without relying on Stewart-electroneutrality considerations.

    PubMed

    Nguyen, Minhtri K; Kao, Liyo; Kurtz, Ira

    2011-01-01

    Upon the addition of protons to an aqueous solution, a component of the H+ load will be bound i.e. buffered. In an aqueous solution containing a triprotic acid, H+ can be bound to three different states of the acid as well as to OH- ions that are derived from the auto-ionization of H2O. In quantifying the buffering process of a triprotic acid, one must define the partitioning of H+ among the three states of the acid and also the OH- ions in solution in order to predict the equilibrium pH value. However, previous quantitative approaches that model triprotic acid titration behaviour and used to predict the equilibrium pH rely on the mathematical convenience of electroneutrality/charge balance considerations. This fact has caused confusion in the literature, and has led to the assumption that charge balance/electroneutrality is a causal factor in modulating proton buffering (Stewart formulation). However, as we have previously shown, although charge balance can be used mathematically as a convenient tool in deriving various formulae, electroneutrality per se is not a fundamental physicochemical parameter that is mechanistically involved in the underlying buffering and proton transfer reactions. The lack of distinction between a mathematical tool, and a fundamental physicochemical parameter is in part a reason for the current debate regarding the Stewart formulation of acid-base analysis. We therefore posed the following question: Is it possible to generate an equation that defines and predicts the buffering of a triprotic acid that is based only on H+ partitioning without incorporating electroneutrality in the derivation? Towards this goal, we derived our new equation utilizing: 1) partitioning of H+ buffering; 2) conservation of mass; and 3) acid-base equilibria. In validating this model, we compared the predicted equilibrium pH with the measured pH of an aqueous solution consisting of Na2HPO4 to which HCl was added. The measured pH values were in excellent agreement

  5. Defining the buffering process by a triprotic acid without relying on Stewart-electroneutrality considerations.

    PubMed

    Nguyen, Minhtri K; Kao, Liyo; Kurtz, Ira

    2011-08-17

    Upon the addition of protons to an aqueous solution, a component of the H+ load will be bound i.e. buffered. In an aqueous solution containing a triprotic acid, H+ can be bound to three different states of the acid as well as to OH- ions that are derived from the auto-ionization of H2O. In quantifying the buffering process of a triprotic acid, one must define the partitioning of H+ among the three states of the acid and also the OH- ions in solution in order to predict the equilibrium pH value. However, previous quantitative approaches that model triprotic acid titration behaviour and used to predict the equilibrium pH rely on the mathematical convenience of electroneutrality/charge balance considerations. This fact has caused confusion in the literature, and has led to the assumption that charge balance/electroneutrality is a causal factor in modulating proton buffering (Stewart formulation). However, as we have previously shown, although charge balance can be used mathematically as a convenient tool in deriving various formulae, electroneutrality per se is not a fundamental physicochemical parameter that is mechanistically involved in the underlying buffering and proton transfer reactions. The lack of distinction between a mathematical tool, and a fundamental physicochemical parameter is in part a reason for the current debate regarding the Stewart formulation of acid-base analysis. We therefore posed the following question: Is it possible to generate an equation that defines and predicts the buffering of a triprotic acid that is based only on H+ partitioning without incorporating electroneutrality in the derivation? Towards this goal, we derived our new equation utilizing: 1) partitioning of H+ buffering; 2) conservation of mass; and 3) acid-base equilibria. In validating this model, we compared the predicted equilibrium pH with the measured pH of an aqueous solution consisting of Na2HPO4 to which HCl was added. The measured pH values were in excellent agreement

  6. Proper synaptic vesicle formation and neuronal network activity critically rely on syndapin I

    PubMed Central

    Koch, Dennis; Spiwoks-Becker, Isabella; Sabanov, Victor; Sinning, Anne; Dugladze, Tamar; Stellmacher, Anne; Ahuja, Rashmi; Grimm, Julia; Schüler, Susann; Müller, Anke; Angenstein, Frank; Ahmed, Tariq; Diesler, Alexander; Moser, Markus; tom Dieck, Susanne; Spessert, Rainer; Boeckers, Tobias Maria; Fässler, Reinhard; Hübner, Christian Andreas; Balschun, Detlef; Gloveli, Tengis; Kessels, Michael Manfred; Qualmann, Britta

    2011-01-01

    Synaptic transmission relies on effective and accurate compensatory endocytosis. F-BAR proteins may serve as membrane curvature sensors and/or inducers and thereby support membrane remodelling processes; yet, their in vivo functions urgently await disclosure. We demonstrate that the F-BAR protein syndapin I is crucial for proper brain function. Syndapin I knockout (KO) mice suffer from seizures, a phenotype consistent with excessive hippocampal network activity. Loss of syndapin I causes defects in presynaptic membrane trafficking processes, which are especially evident under high-capacity retrieval conditions, accumulation of endocytic intermediates, loss of synaptic vesicle (SV) size control, impaired activity-dependent SV retrieval and defective synaptic activity. Detailed molecular analyses demonstrate that syndapin I plays an important role in the recruitment of all dynamin isoforms, central players in vesicle fission reactions, to the membrane. Consistently, syndapin I KO mice share phenotypes with dynamin I KO mice, whereas their seizure phenotype is very reminiscent of fitful mice expressing a mutant dynamin. Thus, syndapin I acts as pivotal membrane anchoring factor for dynamins during regeneration of SVs. PMID:21926968

  7. Preschoolers' brains rely on semantic cues prior to the mastery of syntax during sentence comprehension

    PubMed Central

    Wu, Chiao-Yi; Vissiennon, Kodjo; Friederici, Angela D.; Brauer, Jens

    2016-01-01

    Sentence comprehension requires the integration of both syntactic and semantic information, the acquisition of which seems to have different trajectories in the developing brain. Using functional magnetic resonance imaging, we examined the neural correlates underlying syntactic and semantic processing during auditory sentence comprehension as well as its development in preschool children by manipulating case marking and animacy hierarchy cues, respectively. A functional segregation was observed within Broca's area in the left inferior frontal gyrus for adults, where the pars opercularis was involved in syntactic processing and the pars triangularis in semantic processing. By contrast, five-year-old children sensitive to animacy hierarchy cues showed diffuse activation for semantic processing in the left inferior frontal and posterior temporal cortices. While no main effect of case marking was found in the left fronto-temporal language network, children with better syntactic skills showed greater neural responses for syntactically complex sentences, most prominently in the posterior superior temporal cortex. The current study provides both behavioral and neural evidence that five-year-old children compared to adults rely more on semantic information than on syntactic cues during sentence comprehension, but with the development of syntactic abilities, their brain activation in the left fronto-temporal network increases for syntactic processing. PMID:26497266

  8. Preschoolers' brains rely on semantic cues prior to the mastery of syntax during sentence comprehension.

    PubMed

    Wu, Chiao-Yi; Vissiennon, Kodjo; Friederici, Angela D; Brauer, Jens

    2016-02-01

    Sentence comprehension requires the integration of both syntactic and semantic information, the acquisition of which seems to have different trajectories in the developing brain. Using functional magnetic resonance imaging, we examined the neural correlates underlying syntactic and semantic processing during auditory sentence comprehension as well as its development in preschool children by manipulating case marking and animacy hierarchy cues, respectively. A functional segregation was observed within Broca's area in the left inferior frontal gyrus for adults, where the pars opercularis was involved in syntactic processing and the pars triangularis in semantic processing. By contrast, five-year-old children sensitive to animacy hierarchy cues showed diffuse activation for semantic processing in the left inferior frontal and posterior temporal cortices. While no main effect of case marking was found in the left fronto-temporal language network, children with better syntactic skills showed greater neural responses for syntactically complex sentences, most prominently in the posterior superior temporal cortex. The current study provides both behavioral and neural evidence that five-year-old children compared to adults rely more on semantic information than on syntactic cues during sentence comprehension, but with the development of syntactic abilities, their brain activation in the left fronto-temporal network increases for syntactic processing. PMID:26497266

  9. Massively parallel conjugate heat transfer methods relying on large eddy simulation applied to an aeronautical combustor

    NASA Astrophysics Data System (ADS)

    Jaure, S.; Duchaine, F.; Staffelbach, G.; Gicquel, L. Y. M.

    2013-01-01

    Optimizing gas turbines is a complex multi-physical and multi-component problem that has long been based on expensive experiments. Today, computer simulation can reduce design process costs and is acknowledged as a promising path for optimization. However, performing such computations using high-fidelity methods such as a large eddy simulation (LES) on gas turbines is challenging. Nevertheless, such simulations become accessible for specific components of gas turbines. These stand-alone simulations face a new challenge: to improve the quality of the results, new physics must be introduced. Therefore, an efficient massively parallel coupling methodology is investigated. The flow solver modeling relies on the LES code AVBP which has already been ported on massively parallel architectures. The conduction solver is based on the same data structure and thus shares its scalability. Accurately coupling these solvers while maintaining their scalability is challenging and is the actual objective of this work. To obtain such goals, a methodology is proposed and different key issues to code the coupling are addressed: convergence, stability, parallel geometry mapping, transfers and interpolation. This methodology is then applied to a real burner configuration, hence demonstrating the possibilities and limitations of the solution.

  10. Early mouse caudal development relies on crosstalk between retinoic acid, Shh and Fgf signalling pathways.

    PubMed

    Ribes, Vanessa; Le Roux, Isabelle; Rhinn, Muriel; Schuhbaur, Brigitte; Dollé, Pascal

    2009-02-01

    The progressive generation of embryonic trunk structures relies on the proper patterning of the caudal epiblast, which involves the integration of several signalling pathways. We have investigated the function of retinoic acid (RA) signalling during this process. We show that, in addition to posterior mesendoderm, primitive streak and node cells transiently express the RA-synthesizing enzyme Raldh2 prior to the headfold stage. RA-responsive cells (detected by the RA-activated RARE-lacZ transgene) are additionally found in the epiblast layer. Analysis of RA-deficient Raldh2(-/-) mutants reveals early caudal patterning defects, with an expansion of primitive streak and mesodermal markers at the expense of markers of the prospective neuroepithelium. As a result, many genes involved in neurogenesis and/or patterning of the embryonic spinal cord are affected in their expression. We demonstrate that RA signalling is required at late gastrulation stages for mesodermal and neural progenitors to respond to the Shh signal. Whole-embryo culture experiments indicate that the proper response of cells to Shh requires two RA-dependent mechanisms: (1) a balanced antagonism between Fgf and RA signals, and (2) a RA-mediated repression of Gli2 expression. Thus, an interplay between RA, Fgf and Shh signalling is likely to be an important mechanism underpinning the tight regulation of caudal embryonic development. PMID:19168680

  11. Aquaporins in the antarctic midge, an extremophile that relies on dehydration for cold survival.

    PubMed

    Goto, Shin G; Lee, Richard E; Denlinger, David L

    2015-08-01

    The terrestrial midge Belgica antarctica relies extensively on dehydration to survive the low temperatures and desiccation stress that prevail in its Antarctic habitat. The loss of body water is thus a critical adaptive mechanism employed at the onset of winter to prevent injury from internal ice formation; a rapid mechanism for rehydration is equally essential when summer returns and the larva resumes the brief active phase of its life. This important role for water movement suggests a critical role for aquaporins (AQPs). Recent completion of the genome project on this species revealed the presence of AQPs in B. antarctica representing the DRIP, PRIP, BIB, RPIP, and LHIP families. Treatment with mercuric chloride to block AQPs also blocks water loss, thereby decreasing cell survival at low temperatures. Antibodies directed against mammalian or Drosophila AQPs suggest a wide tissue distribution of AQPs in the midge and changes in protein abundance in response to dehydration, rehydration, and freezing. Thus far, functional studies have been completed only for PRIP1. It appears to be a water-specific AQP, but expression levels are not altered by dehydration or rehydration. Functional assays remain to be completed for the additional AQPs. PMID:26338869

  12. Perceiving racism in ambiguous situations: who relies on easy-to-use information?

    PubMed

    Corning, Alexandra F; Bucchianeri, Michaela M

    2010-01-01

    In situations that are ambiguous with regard to the presence of discrimination, how do people arrive at their conclusions that discrimination has (or has not) taken place? This question was examined from a motivated social cognition perspective via the interaction of two factors: the prototype effect--the notion that ambiguously discriminatory behavior is more likely to be perceived as discriminatory when the executor is prototypical and the need for cognitive closure--the tendency to jump hastily to and seize on an answer. Results provided replicating evidence of the prototype effect among European American participants but not among African American participants. Specifically, European Americans were likely to perceive ambiguously racist behavior enacted by a prototypical executor (i.e., a White person) as more discriminatory than the same behavior exhibited by a non-prototypical executor (i.e., a Black person). African American participants, on the other hand, showed no reliance on this simple cognitive heuristic. Furthermore, results showed that European Americans with a higher need for cognitive closure were more likely to rely on the easy-to-use information offered by prototypes. These findings are discussed from a motivated social cognition perspective.

  13. Frugivorous bats maintain functional habitat connectivity in agricultural landscapes but rely strongly on natural forest fragments.

    PubMed

    Ripperger, Simon P; Kalko, Elisabeth K V; Rodríguez-Herrera, Bernal; Mayer, Frieder; Tschapka, Marco

    2015-01-01

    Anthropogenic changes in land use threaten biodiversity and ecosystem functioning by the conversion of natural habitat into agricultural mosaic landscapes, often with drastic consequences for the associated fauna. The first step in the development of efficient conservation plans is to understand movement of animals through complex habitat mosaics. Therefore, we studied ranging behavior and habitat use in Dermanura watsoni (Phyllostomidae), a frugivorous bat species that is a valuable seed disperser in degraded ecosystems. Radio-tracking of sixteen bats showed that the animals strongly rely on natural forest. Day roosts were exclusively located within mature forest fragments. Selection ratios showed that the bats foraged selectively within the available habitat and positively selected natural forest. However, larger daily ranges were associated with higher use of degraded habitats. Home range geometry and composition of focal foraging areas indicated that wider ranging bats performed directional foraging bouts from natural to degraded forest sites traversing the matrix over distances of up to three hundred meters. This behavior demonstrates the potential of frugivorous bats to functionally connect fragmented areas by providing ecosystem services between natural and degraded sites, and highlights the need for conservation of natural habitat patches within agricultural landscapes that meet the roosting requirements of bats.

  14. Hyperaccumulator Alyssum murale Relies on a Different Metal Storage Mechanism for Cobalt than for Nickel

    SciTech Connect

    Tappero, R.; Peltier, E; Grafe, M; Heidel, K; Ginder-Vogel, M; Livi, K; Rivers, M; Marcus, M; Chaney, R; Sparks, D

    2007-01-01

    The nickel (Ni) hyperaccumulator Alyssum murale has been developed as a commercial crop for phytoremediation/phytomining Ni from metal-enriched soils. Here, metal co-tolerance, accumulation and localization were investigated for A. murale exposed to metal co-contaminants. A. murale was irrigated with Ni-enriched nutrient solutions containing basal or elevated concentrations of cobalt (Co) or zinc (Zn). Metal localization and elemental associations were investigated in situ with synchrotron X-ray microfluorescence (SXRF) and computed-microtomography (CMT). A. murale hyperaccumulated Ni and Co (> 1000 {micro}g g{sup -1} dry weight) from mixed-metal systems. Zinc was not hyperaccumulated. Elevated Co or Zn concentrations did not alter Ni accumulation or localization. SXRF images showed uniform Ni distribution in leaves and preferential localization of Co near leaf tips/margins. CMT images revealed that leaf epidermal tissue was enriched with Ni but devoid of Co, that Co was localized in the apoplasm of leaf ground tissue and that Co was sequestered on leaf surfaces near the tips/margins. Cobalt-rich mineral precipitate(s) form on leaves of Co-treated A. murale. Specialized biochemical processes linked with Ni (hyper)tolerance in A. murale do not confer (hyper)tolerance to Co. A. murale relies on a different metal storage mechanism for Co (exocellular sequestration) than for Ni (vacuolar sequestration).

  15. Pneumococcal Competence Coordination Relies on a Cell-Contact Sensing Mechanism

    PubMed Central

    Prudhomme, Marc; Berge, Mathieu; Martin, Bernard; Polard, Patrice

    2016-01-01

    Bacteria have evolved various inducible genetic programs to face many types of stress that challenge their growth and survival. Competence is one such program. It enables genetic transformation, a major horizontal gene transfer process. Competence development in liquid cultures of Streptococcus pneumoniae is synchronized within the whole cell population. This collective behavior is known to depend on an exported signaling Competence Stimulating Peptide (CSP), whose action generates a positive feedback loop. However, it is unclear how this CSP-dependent population switch is coordinated. By monitoring spontaneous competence development in real time during growth of four distinct pneumococcal lineages, we have found that competence shift in the population relies on a self-activated cell fraction that arises via a growth time-dependent mechanism. We demonstrate that CSP remains bound to cells during this event, and conclude that the rate of competence development corresponds to the propagation of competence by contact between activated and quiescent cells. We validated this two-step cell-contact sensing mechanism by measuring competence development during co-cultivation of strains with altered capacity to produce or respond to CSP. Finally, we found that the membrane protein ComD retains the CSP, limiting its free diffusion in the medium. We propose that competence initiator cells originate stochastically in response to stress, to form a distinct subpopulation that then transmits the CSP by cell-cell contact. PMID:27355362

  16. Aquaporins in the antarctic midge, an extremophile that relies on dehydration for cold survival.

    PubMed

    Goto, Shin G; Lee, Richard E; Denlinger, David L

    2015-08-01

    The terrestrial midge Belgica antarctica relies extensively on dehydration to survive the low temperatures and desiccation stress that prevail in its Antarctic habitat. The loss of body water is thus a critical adaptive mechanism employed at the onset of winter to prevent injury from internal ice formation; a rapid mechanism for rehydration is equally essential when summer returns and the larva resumes the brief active phase of its life. This important role for water movement suggests a critical role for aquaporins (AQPs). Recent completion of the genome project on this species revealed the presence of AQPs in B. antarctica representing the DRIP, PRIP, BIB, RPIP, and LHIP families. Treatment with mercuric chloride to block AQPs also blocks water loss, thereby decreasing cell survival at low temperatures. Antibodies directed against mammalian or Drosophila AQPs suggest a wide tissue distribution of AQPs in the midge and changes in protein abundance in response to dehydration, rehydration, and freezing. Thus far, functional studies have been completed only for PRIP1. It appears to be a water-specific AQP, but expression levels are not altered by dehydration or rehydration. Functional assays remain to be completed for the additional AQPs.

  17. Mouse V1 population correlates of visual detection rely on heterogeneity within neuronal response patterns

    PubMed Central

    Montijn, Jorrit S; Goltstein, Pieter M; Pennartz, Cyriel MA

    2015-01-01

    Previous studies have demonstrated the importance of the primary sensory cortex for the detection, discrimination, and awareness of visual stimuli, but it is unknown how neuronal populations in this area process detected and undetected stimuli differently. Critical differences may reside in the mean strength of responses to visual stimuli, as reflected in bulk signals detectable in functional magnetic resonance imaging, electro-encephalogram, or magnetoencephalography studies, or may be more subtly composed of differentiated activity of individual sensory neurons. Quantifying single-cell Ca2+ responses to visual stimuli recorded with in vivo two-photon imaging, we found that visual detection correlates more strongly with population response heterogeneity rather than overall response strength. Moreover, neuronal populations showed consistencies in activation patterns across temporally spaced trials in association with hit responses, but not during nondetections. Contrary to models relying on temporally stable networks or bulk signaling, these results suggest that detection depends on transient differentiation in neuronal activity within cortical populations. DOI: http://dx.doi.org/10.7554/eLife.10163.001 PMID:26646184

  18. Host adaptation to viruses relies on few genes with different cross-resistance properties.

    PubMed

    Martins, Nelson E; Faria, Vítor G; Nolte, Viola; Schlötterer, Christian; Teixeira, Luis; Sucena, Élio; Magalhães, Sara

    2014-04-22

    Host adaptation to one parasite may affect its response to others. However, the genetics of these direct and correlated responses remains poorly studied. The overlap between these responses is instrumental for the understanding of host evolution in multiparasite environments. We determined the genetic and phenotypic changes underlying adaptation of Drosophila melanogaster to Drosophila C virus (DCV). Within 20 generations, flies selected with DCV showed increased survival after DCV infection, but also after cricket paralysis virus (CrPV) and flock house virus (FHV) infection. Whole-genome sequencing identified two regions of significant differentiation among treatments, from which candidate genes were functionally tested with RNAi. Three genes were validated--pastrel, a known DCV-response gene, and two other loci, Ubc-E2H and CG8492. Knockdown of Ubc-E2H and pastrel also led to increased sensitivity to CrPV, whereas knockdown of CG8492 increased susceptibility to FHV infection. Therefore, Drosophila adaptation to DCV relies on few major genes, each with different cross-resistance properties, conferring host resistance to several parasites.

  19. Activation of G Proteins by Guanine Nucleotide Exchange Factors Relies on GTPase Activity.

    PubMed

    Stanley, Rob J; Thomas, Geraint M H

    2016-01-01

    G proteins are an important family of signalling molecules controlled by guanine nucleotide exchange and GTPase activity in what is commonly called an 'activation/inactivation cycle'. The molecular mechanism by which guanine nucleotide exchange factors (GEFs) catalyse the activation of monomeric G proteins is well-established, however the complete reversibility of this mechanism is often overlooked. Here, we use a theoretical approach to prove that GEFs are unable to positively control G protein systems at steady-state in the absence of GTPase activity. Instead, positive regulation of G proteins must be seen as a product of the competition between guanine nucleotide exchange and GTPase activity--emphasising a central role for GTPase activity beyond merely signal termination. We conclude that a more accurate description of the regulation of G proteins via these processes is as a 'balance/imbalance' mechanism. This result has implications for the understanding of intracellular signalling processes, and for experimental strategies that rely on modulating G protein systems. PMID:26986850

  20. Frugivorous Bats Maintain Functional Habitat Connectivity in Agricultural Landscapes but Rely Strongly on Natural Forest Fragments

    PubMed Central

    Ripperger, Simon P.; Kalko, Elisabeth K. V.; Rodríguez-Herrera, Bernal; Mayer, Frieder; Tschapka, Marco

    2015-01-01

    Anthropogenic changes in land use threaten biodiversity and ecosystem functioning by the conversion of natural habitat into agricultural mosaic landscapes, often with drastic consequences for the associated fauna. The first step in the development of efficient conservation plans is to understand movement of animals through complex habitat mosaics. Therefore, we studied ranging behavior and habitat use in Dermanura watsoni (Phyllostomidae), a frugivorous bat species that is a valuable seed disperser in degraded ecosystems. Radio-tracking of sixteen bats showed that the animals strongly rely on natural forest. Day roosts were exclusively located within mature forest fragments. Selection ratios showed that the bats foraged selectively within the available habitat and positively selected natural forest. However, larger daily ranges were associated with higher use of degraded habitats. Home range geometry and composition of focal foraging areas indicated that wider ranging bats performed directional foraging bouts from natural to degraded forest sites traversing the matrix over distances of up to three hundred meters. This behavior demonstrates the potential of frugivorous bats to functionally connect fragmented areas by providing ecosystem services between natural and degraded sites, and highlights the need for conservation of natural habitat patches within agricultural landscapes that meet the roosting requirements of bats. PMID:25830222

  1. Chlamydia trachomatis Relies on Autonomous Phospholipid Synthesis for Membrane Biogenesis*♦

    PubMed Central

    Yao, Jiangwei; Cherian, Philip T.; Frank, Matthew W.; Rock, Charles O.

    2015-01-01

    The obligate intracellular parasite Chlamydia trachomatis has a reduced genome and is thought to rely on its mammalian host cell for nutrients. Although several lines of evidence suggest C. trachomatis utilizes host phospholipids, the bacterium encodes all the genes necessary for fatty acid and phospholipid synthesis found in free living Gram-negative bacteria. Bacterially derived phospholipids significantly increased in infected HeLa cell cultures. These new phospholipids had a distinct molecular species composition consisting of saturated and branched-chain fatty acids. Biochemical analysis established the role of C. trachomatis-encoded acyltransferases in producing the new disaturated molecular species. There was no evidence for the remodeling of host phospholipids and no change in the size or molecular species composition of the phosphatidylcholine pool in infected HeLa cells. Host sphingomyelin was associated with C. trachomatis isolated by detergent extraction, but it may represent contamination with detergent-insoluble host lipids rather than being an integral bacterial membrane component. C. trachomatis assembles its membrane systems from the unique phospholipid molecular species produced by its own fatty acid and phospholipid biosynthetic machinery utilizing glucose, isoleucine, and serine. PMID:25995447

  2. Pneumococcal Competence Coordination Relies on a Cell-Contact Sensing Mechanism.

    PubMed

    Prudhomme, Marc; Berge, Mathieu; Martin, Bernard; Polard, Patrice

    2016-06-01

    Bacteria have evolved various inducible genetic programs to face many types of stress that challenge their growth and survival. Competence is one such program. It enables genetic transformation, a major horizontal gene transfer process. Competence development in liquid cultures of Streptococcus pneumoniae is synchronized within the whole cell population. This collective behavior is known to depend on an exported signaling Competence Stimulating Peptide (CSP), whose action generates a positive feedback loop. However, it is unclear how this CSP-dependent population switch is coordinated. By monitoring spontaneous competence development in real time during growth of four distinct pneumococcal lineages, we have found that competence shift in the population relies on a self-activated cell fraction that arises via a growth time-dependent mechanism. We demonstrate that CSP remains bound to cells during this event, and conclude that the rate of competence development corresponds to the propagation of competence by contact between activated and quiescent cells. We validated this two-step cell-contact sensing mechanism by measuring competence development during co-cultivation of strains with altered capacity to produce or respond to CSP. Finally, we found that the membrane protein ComD retains the CSP, limiting its free diffusion in the medium. We propose that competence initiator cells originate stochastically in response to stress, to form a distinct subpopulation that then transmits the CSP by cell-cell contact. PMID:27355362

  3. Drug-induced reactive oxygen species (ROS) rely on cell membrane properties to exert anticancer effects

    PubMed Central

    Molavian, Hamid R.; Goldman, Aaron; Phipps, Colin J.; Kohandel, Mohammad; Wouters, Bradly G.; Sengupta, Shiladitya; Sivaloganathan, Sivabal

    2016-01-01

    Pharmacological concentrations of small molecule natural products, such as ascorbic acid, have exhibited distinct cell killing outcomes between cancer and normal cells whereby cancer cells undergo apoptosis or necrosis while normal cells are not adversely affected. Here, we develop a mathematical model for ascorbic acid that can be utilized as a tool to understand the dynamics of reactive oxygen species (ROS) induced cell death. We determine that not only do endogenous antioxidants such as catalase contribute to ROS-induced cell death, but also cell membrane properties play a critical role in the efficacy of ROS as a cytotoxic mechanism against cancer cells vs. normal cells. Using in vitro assays with breast cancer cells, we have confirmed that cell membrane properties are essential for ROS, in the form of hydrogen peroxide (H2O2), to induce cell death. Interestingly, we did not observe any correlation between intracellular H2O2 and cell survival, suggesting that cell death by H2O2 is triggered by interaction with the cell membrane and not necessarily due to intracellular levels of H2O2. These findings provide a putative mechanistic explanation for the efficacy and selectivity of therapies such as ascorbic acid that rely on ROS-induced cell death for their anti-tumor properties. PMID:27278439

  4. Regulation of Carotenoid Biosynthesis by Shade Relies on Specific Subsets of Antagonistic Transcription Factors and Cofactors.

    PubMed

    Bou-Torrent, Jordi; Toledo-Ortiz, Gabriela; Ortiz-Alcaide, Miriam; Cifuentes-Esquivel, Nicolas; Halliday, Karen J; Martinez-García, Jaime F; Rodriguez-Concepcion, Manuel

    2015-11-01

    Carotenoids are photosynthetic pigments essential for the protection against excess light. During deetiolation, their production is regulated by a dynamic repression-activation module formed by PHYTOCHROME-INTERACTING FACTOR1 (PIF1) and LONG HYPOCOTYL5 (HY5). These transcription factors directly and oppositely control the expression of the gene encoding PHYTOENE SYNTHASE (PSY), the first and main rate-determining enzyme of the carotenoid pathway. Antagonistic modules also regulate the responses of deetiolated plants to vegetation proximity and shade (i.e. to the perception of far-red light-enriched light filtered through or reflected from neighboring plants). These responses, aimed to adapt to eventual shading from plant competitors, include a reduced accumulation of carotenoids. Here, we show that PIF1 and related photolabile PIFs (but not photostable PIF7) promote the shade-triggered decrease in carotenoid accumulation. While HY5 does not appear to be required for this process, other known PIF antagonists were found to modulate the expression of the Arabidopsis (Arabidopsis thaliana) PSY gene and the biosynthesis of carotenoids early after exposure to shade. In particular, PHYTOCHROME-RAPIDLY REGULATED1, a transcriptional cofactor that prevents the binding of true transcription factors to their target promoters, was found to interact with PIF1 and hence directly induce PSY expression. By contrast, a change in the levels of the transcriptional cofactor LONG HYPOCOTYL IN FAR RED1, which also binds to PIF1 and other PIFs to regulate shade-related elongation responses, did not impact PSY expression or carotenoid accumulation. Our data suggest that the fine-regulation of carotenoid biosynthesis in response to shade relies on specific modules of antagonistic transcriptional factors and cofactors.

  5. High sugar-induced insulin resistance in Drosophila relies on the lipocalin Neural Lazarillo.

    PubMed

    Pasco, Matthieu Y; Léopold, Pierre

    2012-01-01

    In multicellular organisms, insulin/IGF signaling (IIS) plays a central role in matching energy needs with uptake and storage, participating in functions as diverse as metabolic homeostasis, growth, reproduction and ageing. In mammals, this pleiotropy of action relies in part on a dichotomy of action of insulin, IGF-I and their respective membrane-bound receptors. In organisms with simpler IIS, this functional separation is questionable. In Drosophila IIS consists of several insulin-like peptides called Dilps, activating a unique membrane receptor and its downstream signaling cascade. During larval development, IIS is involved in metabolic homeostasis and growth. We have used feeding conditions (high sugar diet, HSD) that induce an important change in metabolic homeostasis to monitor possible effects on growth. Unexpectedly we observed that HSD-fed animals exhibited severe growth inhibition as a consequence of peripheral Dilp resistance. Dilp-resistant animals present several metabolic disorders similar to those observed in type II diabetes (T2D) patients. By exploring the molecular mechanisms involved in Drosophila Dilp resistance, we found a major role for the lipocalin Neural Lazarillo (NLaz), a target of JNK signaling. NLaz expression is strongly increased upon HSD and animals heterozygous for an NLaz null mutation are fully protected from HSD-induced Dilp resistance. NLaz is a secreted protein homologous to the Retinol-Binding Protein 4 involved in the onset of T2D in human and mice. These results indicate that insulin resistance shares common molecular mechanisms in flies and human and that Drosophila could emerge as a powerful genetic system to study some aspects of this complex syndrome.

  6. Secreted autotransporter toxin (Sat) triggers autophagy in epithelial cells that relies on cell detachment.

    PubMed

    Liévin-Le Moal, Vanessa; Comenge, Yannick; Ruby, Vincent; Amsellem, Raymonde; Nicolas, Valérie; Servin, Alain L

    2011-07-01

    The secreted autotransporter toxin, Sat, which belongs to the subfamily of serine protease autotransporters of Enterobacteriaceae, acts as a virulence factor in extraintestinal and intestinal pathogenic strains of Escherichia coli. We observed that HeLa cells exposed to the cell-free culture supernatant of recombinant strain AAEC185p(Sat-IH11128) producing the Sat toxin (CFCS(Sat) ), displayed dramatic disorganization of the F-actin cytoskeleton before loosening cell-to-cell junctions and detachment. Examination of the effect of Sat on GFP-microtubule-associated protein light chain 3 (LC3) HeLa cells revealed that CFCS(Sat) -induced autophagy follows CFCS(Sat) -induced F-actin cytoskeleton rearrangement. The induced autophagy shows an acceleration of the autophagy flux soon after Sat treatment, followed later by a blockade of the flux leading to the accumulation of large GFP-LC3-positive vacuoles in the cell cytoplasm. CFCS(Sat) did not induce cell detachment in autophagy-deficient mouse embryonic fibroblasts in contrast with wild-type mouse embryonic fibroblasts. The CFCS(Sat) -induced large GFP-LC3 dots do not display the characteristics of autophagolysosomes including expression of cathepsin D and Lamp-1 and 2 proteins, and Lysotracker Red- and DQ-BSA-positive labelling. We provide evidences that CFCS(Sat) -induced autophagy is not a cell response intended to get rid of the intracellular toxin. By a pharmacological blockers approach, we found that the blockade of Erk1/2 and p38 MAPKs, but not JNK, inhibited the CFCS(Sat) -induced autophagy and cell detachment whereas phosphatidylinositol-3 kinase blockers inhibiting canonical autophagy were inactive. When attached CFCS(Sat) -treated cells start to detach they showed caspase-independent cell death and rearrangements of the focal adhesion-associated vinculin and paxillin. Collectively, our results support that Sat triggers autophagy in epithelial cells that relies on its cell-detachment effect. PMID:21501364

  7. High Sugar-Induced Insulin Resistance in Drosophila Relies on the Lipocalin Neural Lazarillo

    PubMed Central

    Pasco, Matthieu Y.; Léopold, Pierre

    2012-01-01

    In multicellular organisms, insulin/IGF signaling (IIS) plays a central role in matching energy needs with uptake and storage, participating in functions as diverse as metabolic homeostasis, growth, reproduction and ageing. In mammals, this pleiotropy of action relies in part on a dichotomy of action of insulin, IGF-I and their respective membrane-bound receptors. In organisms with simpler IIS, this functional separation is questionable. In Drosophila IIS consists of several insulin-like peptides called Dilps, activating a unique membrane receptor and its downstream signaling cascade. During larval development, IIS is involved in metabolic homeostasis and growth. We have used feeding conditions (high sugar diet, HSD) that induce an important change in metabolic homeostasis to monitor possible effects on growth. Unexpectedly we observed that HSD-fed animals exhibited severe growth inhibition as a consequence of peripheral Dilp resistance. Dilp-resistant animals present several metabolic disorders similar to those observed in type II diabetes (T2D) patients. By exploring the molecular mechanisms involved in Drosophila Dilp resistance, we found a major role for the lipocalin Neural Lazarillo (NLaz), a target of JNK signaling. NLaz expression is strongly increased upon HSD and animals heterozygous for an NLaz null mutation are fully protected from HSD-induced Dilp resistance. NLaz is a secreted protein homologous to the Retinol-Binding Protein 4 involved in the onset of T2D in human and mice. These results indicate that insulin resistance shares common molecular mechanisms in flies and human and that Drosophila could emerge as a powerful genetic system to study some aspects of this complex syndrome. PMID:22567167

  8. Fruit production in three masting tree species does not rely on stored carbon reserves.

    PubMed

    Hoch, Günter; Siegwolf, Rolf T W; Keel, Sonja G; Körner, Christian; Han, Qingmin

    2013-03-01

    Fruiting is typically considered to massively burden the seasonal carbon budget of trees. The cost of reproduction has therefore been suggested as a proximate factor explaining observed mast-fruiting patterns. Here, we used a large-scale, continuous (13)C labeling of mature, deciduous trees in a temperate Swiss forest to investigate to what extent fruit formation in three species with masting reproduction behavior (Carpinus betulus, Fagus sylvatica, Quercus petraea) relies on the import of stored carbon reserves. Using a free-air CO2 enrichment system, we exposed trees to (13)C-depleted CO2 during 8 consecutive years. By the end of this experiment, carbon reserve pools had significantly lower δ(13)C values compared to control trees. δ(13)C analysis of new biomass during the first season after termination of the CO2 enrichment allowed us to distinguish the sources of built-in carbon (old carbon reserves vs. current assimilates). Flowers and expanding leaves carried a significant (13)C label from old carbon stores. In contrast, fruits and vegetative infructescence tissues were exclusively produced from current, unlabeled photoassimilates in all three species, including F. sylvatica, which had a strong masting season. Analyses of δ(13)C in purified starch from xylem of fruit-bearing shoots revealed a complete turn-over of starch during the season, likely due to its usage for bud break. This study is the first to directly demonstrate that fruiting is independent from old carbon reserves in masting trees, with significant implications for mechanistic models that explain mast seeding.

  9. You can't rely on color, yet we all do 2.0 (Manuscript Only)

    NASA Astrophysics Data System (ADS)

    van Nes, Floris L.

    2014-01-01

    Everybody views and uses color from early childhood onwards. But this magnificent property of all objects around us turns out to be elusive if you try to specify it and communicate it to another person. Also, people often don't know what effects color may have under different conditions. However, color is so important and omnipresent, that people can hardly avoid to 'rely on it' - so they do, in particular on its predictability. Thus, there is a discrepancy between the seeming self-evidence of color and the difficulty in specifying it accurately, for the prevailing circumstances. In order to analyze this situation, and possibly remedy it, a short historic perspective of the utilization and specification of color is given. The 'utilization' includes the emotional effects of color, which are important in, for instance, interior decorating but also play a role in literature and religion. 'Specification' begins with the early efforts by scientists, philosophers and artists to bring some order and understanding in what was observed with and while using color. Color has a number of basic functions: embellishment; attracting attention; coding; and bringing order in text by causing text parts presented in the same color to be judged as belonging together. People with a profession that involves color choices for many others, such as designers and manufacturers of products, including electronic visual displays, should have a fairly thorough knowledge of colorimetry and color perception. Unfortunately, they often don't, simply because for 'practitioners' whose work involves different aspects, applying color being only one of those, the available tools for specifying and applying color turn out to be too difficult to use. Two consequences of an insufficient knowledge of the effects color may have are given here. The first of these consequences, on color blindness, relates to 8% of the population, but the second one, on reading colored text, bears on everyone. Practical

  10. A zinc(II) quinolinone complex (Et3NH)[Zn(qui)Cl2]: Synthesis, X-ray structure, spectral properties and in vitro cytotoxicity

    NASA Astrophysics Data System (ADS)

    Buchtík, Roman; Nemec, Ivan; Trávníček, Zdeněk

    2014-02-01

    A new zinc(II) complex with 2-phenyl-3-hydroxy-4(1H)-quinolinone (Hqui) of the composition (Et3NH)[Zn(qui)Cl2] was prepared and characterized by elemental analysis, FT IR, 1D and 2D NMR, and fluorescence spectroscopy, mass spectrometry and single crystal X-ray analysis. The molecular structure is composed of the triethylammonium (Et3NH+) cations and tetrahedral [ZnII(qui)Cl2]- complex anions, in which the Zn(II) atoms are bidentate coordinated by one qui ligand through keto (OK) and phenolate (OP) oxygen atoms and by two chlorido ligands, thus forming the {O2Cl2} donor set, with Zn-OK = 1.9860(14) Å, Zn-OP 1.9961(14) Å and Zn-Cl = 2.2509(6) Å and 2.2266(6) Å. The complex cations are aligned into 1D supramolecular chains through the NH⋯Cl hydrogen bonding between the amine group of the quinolinone ligand and the chlorido ligand of the adjacent complex anion. The amine group from the Et3NH+ cations provides the NH⋯OP hydrogen bond with the phenolate oxygen atoms from the complex anion. Screening of in vitro cytotoxicity of the compound was studied on human osteosarcoma (HOS) and human breast adenocarcinoma (MCF7) cell lines, with IC50 > 50 μM. The fluorescence study showed that the complex exhibits a relatively high integral intensity (29%) as compared to the standard quinine sulfate, and 1.6-fold enhancement of emission with respect to free Hqui.

  11. Immobilization of α-Amylase from Anoxybacillus sp. SK3-4 on ReliZyme and Immobead Supports.

    PubMed

    Kahar, Ummirul Mukminin; Sani, Mohd Helmi; Chan, Kok-Gan; Goh, Kian Mau

    2016-01-01

    α-Amylase from Anoxybacillus sp. SK3-4 (ASKA) is a thermostable enzyme that produces a high level of maltose from starches. A truncated ASKA (TASKA) variant with improved expression and purification efficiency was characterized in an earlier study. In this work, TASKA was purified and immobilized through covalent attachment on three epoxide (ReliZyme EP403/M, Immobead IB-150P, and Immobead IB-150A) and an amino-epoxide (ReliZyme HFA403/M) activated supports. Several parameters affecting immobilization were analyzed, including the pH, temperature, and quantity (mg) of enzyme added per gram of support. The influence of the carrier surface properties, pore sizes, and lengths of spacer arms (functional groups) on biocatalyst performances were studied. Free and immobilized TASKAs were stable at pH 6.0-9.0 and active at pH 8.0. The enzyme showed optimal activity and considerable stability at 60 °C. Immobilized TASKA retained 50% of its initial activity after 5-12 cycles of reuse. Upon degradation of starches and amylose, only immobilized TASKA on ReliZyme HFA403/M has comparable hydrolytic ability with the free enzyme. To the best of our knowledge, this is the first report of an immobilization study of an α-amylase from Anoxybacillus spp. and the first report of α-amylase immobilization using ReliZyme and Immobeads as supports. PMID:27618002

  12. 78 FR 29392 - Embedded Digital Devices in Safety-Related Systems, Systems Important to Safety, and Items Relied...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-20

    ... COMMISSION Embedded Digital Devices in Safety-Related Systems, Systems Important to Safety, and Items Relied... Regulatory Issue Summary (RIS) 2013-XX, ``Embedded Digital Devices in Safety-Related Systems, Systems... Draft Regulatory Issue Summary (RIS) 2013-XX, ``Embedded Digital Devices in Safety-Related...

  13. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  14. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  15. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  16. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  17. 39 CFR 3050.12 - Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Obsolescence of special studies relied on to produce the Postal Service's annual periodic reports to the Commission. 3050.12 Section 3050.12 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.12 Obsolescence of...

  18. Safety Relies on Climate

    ERIC Educational Resources Information Center

    Kinney, Patti

    2009-01-01

    One of the most important challenges of a principal's day is that of building and maintaining a school culture that promotes safety and supports learning. So it should come as no surprise to experienced educators that school safety and positive school climate directly affect academic achievement. This article discusses how principals can build an…

  19. Someone to rely on.

    PubMed

    2014-05-13

    When Yvonne Pywell was admitted to the Welland Centre at St Mary's Hospital in Kettering over Christmas with severe depression, 'calm, caring, compassionate and capable' healthcare assistant Paula Lawrence of Northamptonshire Healthcare NHS Foundation Trust became her refuge.

  20. ARISTOTLE RE-LYs on the ROCKET. What's new in stroke prevention in patients with atrial fibrillation?

    PubMed

    Tendera, Michał; Syzdół, Marcin; Parma, Zofia

    2012-01-01

    Warfarin has long been considered the gold standard for stroke prevention in patients with atrial fibrillation (AF). Recently, three major trials comparing the efficacy and safety of new drugs: a thrombin inhibitor dabigatran and two inhibitors of factor Xa - rivaroxaban and apixaban, with that of warfarin, have been published. The aim of this paper is to present the main results of the RE-LY, ROCKET AF and ARISTOTLE trials, compare study populations and outcomes, and discuss clinical implications of their results for the long-term anticoagulation in patients with nonvalvular AF.

  1. Relying on procedural memory to enhance independence in daily living activities: Smartphone use in a case of semantic dementia.

    PubMed

    Bier, N; Brambati, S; Macoir, J; Paquette, G; Schmitz, X; Belleville, S; Faucher, C; Joubert, S

    2015-01-01

    Relying on procedural memory is a promising approach for interventions that address the cognitive difficulties found in semantic dementia. The aim of this study was to determine if procedural memory could be used to optimise learning of relevant smartphone functions in MH, a 55-year-old man with semantic dementia. The impact of learning to use specific smartphone applications, which display concepts and their semantic characteristics, on relearning useful significant concepts, was also explored in MH. This patient, who showed no deficits in procedural learning on a serial reaction time paradigm, was able to learn manipulations related to 15 smartphone functions although, because of his deficit in word comprehension, he generally needed verbal cues to clarify which functions he was asked to perform. Six months after the end of the intervention, he was still using 8 of the 15 functions regularly. However, repeated exposure to concepts through the use of two applications did not improve naming or retrieval of semantic attributes. This study showed the potential of relying on procedural memory to optimise learning of new technologies in the ecological rehabilitation of semantic dementia.

  2. Visual control of action directed toward two-dimensional objects relies on holistic processing of object shape.

    PubMed

    Freud, Erez; Ganel, Tzvi

    2015-10-01

    Visual perception relies on holistic processing of object shape. In contrast to perception, previous studies demonstrated that vision-for-action operates in a fundamentally different manner based on an analytical representation of objects. This notion was mainly supported by the absence of Garner interference for visually guided actions, compared to robust interference effects for perceptual estimations of the same objects. This study examines the nature of the representations that subserve visually guided actions toward two-dimensional (2D) stimuli. Based on recent results suggesting that actions directed toward 2D objects are mediated by different underlying processes compared to normal actions, we predicted that visually guided actions toward 2D stimuli would rely on perceptually driven holistic representations of object shape. To test this idea, we asked participants to grasp 2D rectangular objects presented on a computer monitor along their width while the values of the irrelevant dimension of length were either kept constant (baseline condition) or varied between trials (filtering condition). Worse performance in the filtering blocks is labeled Garner interference, which indicates holistic processing of object shape. Unlike in previous studies that used real objects, the results showed that grasping toward 2D objects produced a significant Garner interference effect, with more variable within-subject performance in the filtering compared to the baseline blocks. This finding suggests that visually guided actions directed toward 2D targets are mediated by different computations compared to visually guided actions directed toward real objects.

  3. Can we rely on the antiretroviral treatment as the only means for human immunodeficiency virusprevention? A Public Health perspective.

    PubMed

    Mozalevskis, Antons; Manzanares-Laya, Sandra; García de Olalla, Patricia; Moreno, Antonio; Jacques-Aviñó, Constanza; Caylà, Joan A

    2015-11-01

    The evidence that supports the preventive effect of combination antiretroviral treatment (cART) in HIV sexual transmission suggested the so-called 'treatment as prevention' (TAP) strategy as a promising tool for slowing down HIV transmission. As the messages and attitudes towards condom use in the context of TAP appear to be somehow confusing, the aim here is to assess whether relying on cART alone to prevent HIV transmission can currently be recommended from the Public Health perspective. A review is made of the literature on the effects of TAP strategy on HIV transmission and the epidemiology of other sexual transmitted infections (STIs) in the cART era, and recommendations from Public Health institutions on the TAP as of February 2014. The evolution of HIV and other STIs in Barcelona from 2007 to 2012 has also been analysed. Given that the widespread use of cART has coincided with an increasing incidence of HIV and other STIs, mainly amongst men who have sex with men, a combination and diversified prevention methods should always be considered and recommended in counselling. An informed decision on whether to stop using condoms should only be made by partners within stable couples, and after receiving all the up-to-date information regarding TAP. From the public health perspective, primary prevention should be a priority; therefore relying on cART alone is not a sufficient strategy to prevent new HIV and other STIs.

  4. Patient outcomes using the European label for dabigatran. A post-hoc analysis from the RE-LY database.

    PubMed

    Lip, Gregory Y H; Clemens, Andreas; Noack, Herbert; Ferreira, Jorge; Connolly, Stuart J; Yusuf, Salim

    2014-05-01

    In the RE-LY trial dabigatran 150 mg twice daily (D150) showed significantly fewer strokes, and 110 mg (D110) significantly fewer major bleeding events (MBE) compared to well-controlled warfarin in patients with atrial fibrillation (AF). The European (EU) label currently recommends the use of D150 in AF patients who are aged < 80 years without an increased risk for bleeding (e.g. HAS-BLED score <3) and not on concomitant verapamil. In other patients, D110 is recommended. In this post-hoc analysis of the RE-LY dataset, we simulated how dabigatran (n=6,004) would compare to well-controlled warfarin (n=6,022) used according to the EU label. "EU label simulated dabigatran treatment" was associated with significant reductions in stroke and systemic embolism (hazard ratio [HR] 0.74; 95% confidence interval [CI] 0.60-0.91), haemorrhagic stroke (HR 0.22; 95%CI 0.11-0.44), death (HR 0.86; 95%CI 0.75-0.98), and vascular death (HR 0.80; 95%CI 0.68-0.95) compared to warfarin. Dabigatran was also associated with less major bleeding (HR 0.85; 95%CI 0.73-0.98), life-threatening bleeding (HR 0.72; 95%CI 0.58-0.91), intracranial haemorrhage (HR 0.28; 95%CI 0.17-0.45), and "any bleeds" (HR 0.86; 95%CI 0.81-0.92), but not gastrointestinal major bleeding (HR 1.23; 95%CI 0.96-1.59). The net clinical benefit was significantly better for dabigatran compared to warfarin. In conclusion, this post-hoc simulation of dabigatran usage based on RE-LY trial dataset indicates that "EU label simulated dabigatran treatment" may be associated with superior efficacy and safety compared to warfarin, and are in support of the EU label and the 2012 European Society of Cardiology AF guideline recommendations. Thus, adherence to European label/guideline use results in a clinically relevant benefit for dabigatran over warfarin, for both efficacy and safety.

  5. Optimal myelin elongation relies on YAP activation by axonal growth and inhibition by Crb3/Hippo pathway

    PubMed Central

    Fernando, Ruani N.; Cotter, Laurent; Perrin-Tricaud, Claire; Berthelot, Jade; Bartolami, Sylvain; Pereira, Jorge A.; Gonzalez, Sergio; Suter, Ueli; Tricaud, Nicolas

    2016-01-01

    Fast nerve conduction relies on successive myelin segments that electrically isolate axons. Segment geometry—diameter and length—is critical for the optimization of nerve conduction and the molecular mechanisms allowing this optimized geometry are partially known. We show here that peripheral myelin elongation is dynamically regulated by stimulation of YAP (Yes-associated protein) transcription cofactor activity during axonal elongation and limited by inhibition of YAP activity via the Hippo pathway. YAP promotes myelin and non-myelin genes transcription while the polarity protein Crb3, localized at the tips of the myelin sheath, activates the Hippo pathway to temper YAP activity, therefore allowing for optimal myelin growth. Dystrophic Dy2j/2j mice mimicking human peripheral neuropathy with reduced internodal lengths have decreased nuclear YAP which, when corrected, leads to longer internodes. These data show a novel mechanism controlling myelin growth and nerve conduction, and provide a molecular ground for disease with short myelin segments. PMID:27435623

  6. Self-control relies on glucose as a limited energy source: willpower is more than a metaphor.

    PubMed

    Gailliot, Matthew T; Baumeister, Roy F; DeWall, C Nathan; Maner, Jon K; Plant, E Ashby; Tice, Dianne M; Brewer, Lauren E; Schmeichel, Brandon J

    2007-02-01

    The present work suggests that self-control relies on glucose as a limited energy source. Laboratory tests of self-control (i.e., the Stroop task, thought suppression, emotion regulation, attention control) and of social behaviors (i.e., helping behavior, coping with thoughts of death, stifling prejudice during an interracial interaction) showed that (a) acts of self-control reduced blood glucose levels, (b) low levels of blood glucose after an initial self-control task predicted poor performance on a subsequent self-control task, and (c) initial acts of self-control impaired performance on subsequent self-control tasks, but consuming a glucose drink eliminated these impairments. Self-control requires a certain amount of glucose to operate unimpaired. A single act of self-control causes glucose to drop below optimal levels, thereby impairing subsequent attempts at self-control.

  7. Humans rely on the same rules to assess emotional valence and intensity in conspecific and dog vocalizations.

    PubMed

    Faragó, Tamás; Andics, Attila; Devecseri, Viktor; Kis, Anna; Gácsi, Márta; Miklósi, Adám

    2014-01-01

    Humans excel at assessing conspecific emotional valence and intensity, based solely on non-verbal vocal bursts that are also common in other mammals. It is not known, however, whether human listeners rely on similar acoustic cues to assess emotional content in conspecific and heterospecific vocalizations, and which acoustical parameters affect their performance. Here, for the first time, we directly compared the emotional valence and intensity perception of dog and human non-verbal vocalizations. We revealed similar relationships between acoustic features and emotional valence and intensity ratings of human and dog vocalizations: those with shorter call lengths were rated as more positive, whereas those with a higher pitch were rated as more intense. Our findings demonstrate that humans rate conspecific emotional vocalizations along basic acoustic rules, and that they apply similar rules when processing dog vocal expressions. This suggests that humans may utilize similar mental mechanisms for recognizing human and heterospecific vocal emotions.

  8. Humans rely on the same rules to assess emotional valence and intensity in conspecific and dog vocalizations.

    PubMed

    Faragó, Tamás; Andics, Attila; Devecseri, Viktor; Kis, Anna; Gácsi, Márta; Miklósi, Adám

    2014-01-01

    Humans excel at assessing conspecific emotional valence and intensity, based solely on non-verbal vocal bursts that are also common in other mammals. It is not known, however, whether human listeners rely on similar acoustic cues to assess emotional content in conspecific and heterospecific vocalizations, and which acoustical parameters affect their performance. Here, for the first time, we directly compared the emotional valence and intensity perception of dog and human non-verbal vocalizations. We revealed similar relationships between acoustic features and emotional valence and intensity ratings of human and dog vocalizations: those with shorter call lengths were rated as more positive, whereas those with a higher pitch were rated as more intense. Our findings demonstrate that humans rate conspecific emotional vocalizations along basic acoustic rules, and that they apply similar rules when processing dog vocal expressions. This suggests that humans may utilize similar mental mechanisms for recognizing human and heterospecific vocal emotions. PMID:24402716

  9. Humans rely on the same rules to assess emotional valence and intensity in conspecific and dog vocalizations

    PubMed Central

    Faragó, Tamás; Andics, Attila; Devecseri, Viktor; Kis, Anna; Gácsi, Márta; Miklósi, Ádám

    2014-01-01

    Humans excel at assessing conspecific emotional valence and intensity, based solely on non-verbal vocal bursts that are also common in other mammals. It is not known, however, whether human listeners rely on similar acoustic cues to assess emotional content in conspecific and heterospecific vocalizations, and which acoustical parameters affect their performance. Here, for the first time, we directly compared the emotional valence and intensity perception of dog and human non-verbal vocalizations. We revealed similar relationships between acoustic features and emotional valence and intensity ratings of human and dog vocalizations: those with shorter call lengths were rated as more positive, whereas those with a higher pitch were rated as more intense. Our findings demonstrate that humans rate conspecific emotional vocalizations along basic acoustic rules, and that they apply similar rules when processing dog vocal expressions. This suggests that humans may utilize similar mental mechanisms for recognizing human and heterospecific vocal emotions. PMID:24402716

  10. Do intuitive and deliberate judgments rely on two distinct neural systems? A case study in face processing

    PubMed Central

    Mega, Laura F.; Gigerenzer, Gerd; Volz, Kirsten G.

    2015-01-01

    Arguably the most influential models of human decision-making today are based on the assumption that two separable systems – intuition and deliberation – underlie the judgments that people make. Our recent work is among the first to present neural evidence contrary to the predictions of these dual-systems accounts. We measured brain activations using functional magnetic resonance imaging while participants were specifically instructed to either intuitively or deliberately judge the authenticity of emotional facial expressions. Results from three different analyses revealed both common brain networks of activation across decision mode and differential activations as a function of strategy adherence. We take our results to contradict popular dual-systems accounts that propose a clear-cut dichotomy of the processing systems, and to support rather a unified model. According to this, intuitive and deliberate judgment processes rely on the same rules, though only the former are thought to be characterized by non-conscious processing. PMID:26379523

  11. Episodic feeling-of-knowing relies on noncriterial recollection and familiarity: Evidence using an online remember-know procedure.

    PubMed

    Isingrini, Michel; Sacher, Mathilde; Perrotin, Audrey; Taconnat, Laurence; Souchay, Céline; Stoehr, Hélène; Bouazzaoui, Badiâa

    2016-04-01

    We examined the hypothesis that feeling-of-knowing judgments rely on recollection as well as on familiarity prompted by the cue presentation. A remember-know-no memory procedure was combined with the episodic FOK procedure employing a cue-target pair memory task. The magnitude of FOK judgments and FOK accuracy were examined as a function of recollection, familiarity, or the "no memory" option. Results showed that the proportion of R and K responses was similar. FOK accuracy and magnitude of FOK judgments were higher for R and K responses than for N responses. FOK accuracy related to R and K responses were above chance level, but FOK was not accurate in the "no memory" condition. Finally, both FOK magnitude and FOK accuracy were related more to recollection than to familiarity. These results support the hypothesis that both recollection and familiarity are determinants of the FOK process, although they suggest that recollection has a stronger influence. PMID:26849420

  12. Optimal myelin elongation relies on YAP activation by axonal growth and inhibition by Crb3/Hippo pathway.

    PubMed

    Fernando, Ruani N; Cotter, Laurent; Perrin-Tricaud, Claire; Berthelot, Jade; Bartolami, Sylvain; Pereira, Jorge A; Gonzalez, Sergio; Suter, Ueli; Tricaud, Nicolas

    2016-07-20

    Fast nerve conduction relies on successive myelin segments that electrically isolate axons. Segment geometry-diameter and length-is critical for the optimization of nerve conduction and the molecular mechanisms allowing this optimized geometry are partially known. We show here that peripheral myelin elongation is dynamically regulated by stimulation of YAP (Yes-associated protein) transcription cofactor activity during axonal elongation and limited by inhibition of YAP activity via the Hippo pathway. YAP promotes myelin and non-myelin genes transcription while the polarity protein Crb3, localized at the tips of the myelin sheath, activates the Hippo pathway to temper YAP activity, therefore allowing for optimal myelin growth. Dystrophic Dy(2j/2j) mice mimicking human peripheral neuropathy with reduced internodal lengths have decreased nuclear YAP which, when corrected, leads to longer internodes. These data show a novel mechanism controlling myelin growth and nerve conduction, and provide a molecular ground for disease with short myelin segments.

  13. 17 CFR 270.12d1-3 - Exemptions for investment companies relying on section 12(d)(1)(F) of the Act.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Exemption from sales charge limits. A registered investment company (“acquiring fund”) that relies on... company (“acquired fund”) may offer or sell any security it issues through a principal underwriter or... companies relying on section 12(d)(1)(F) of the Act. 270.12d1-3 Section 270.12d1-3 Commodity and...

  14. 21 CFR 314.122 - Submitting an abbreviated application for, or a 505(j)(2)(C) petition that relies on, a listed...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 505(j)(2)(C) petition that relies on, a listed drug that is no longer marketed. 314.122 Section 314... Abbreviated Applications § 314.122 Submitting an abbreviated application for, or a 505(j)(2)(C) petition that... to, or a petition under section 505(j)(2)(C) of the act and § 314.93 that relies on, a listed...

  15. 12 CFR 714.5 - What is required if you rely on an estimated residual value greater than 25% of the original cost...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... residual value greater than 25% of the original cost of the leased property? 714.5 Section 714.5 Banks and... required if you rely on an estimated residual value greater than 25% of the original cost of the leased property? If the amount of the estimated residual value you rely upon to satisfy the full payout...

  16. 12 CFR 714.5 - What is required if you rely on an estimated residual value greater than 25% of the original cost...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... residual value greater than 25% of the original cost of the leased property? 714.5 Section 714.5 Banks and... required if you rely on an estimated residual value greater than 25% of the original cost of the leased property? If the amount of the estimated residual value you rely upon to satisfy the full payout...

  17. 12 CFR 714.5 - What is required if you rely on an estimated residual value greater than 25% of the original cost...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... residual value greater than 25% of the original cost of the leased property? 714.5 Section 714.5 Banks and... required if you rely on an estimated residual value greater than 25% of the original cost of the leased property? If the amount of the estimated residual value you rely upon to satisfy the full payout...

  18. 12 CFR 714.5 - What is required if you rely on an estimated residual value greater than 25% of the original cost...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... residual value greater than 25% of the original cost of the leased property? 714.5 Section 714.5 Banks and... required if you rely on an estimated residual value greater than 25% of the original cost of the leased property? If the amount of the estimated residual value you rely upon to satisfy the full payout...

  19. 12 CFR 714.5 - What is required if you rely on an estimated residual value greater than 25% of the original cost...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... residual value greater than 25% of the original cost of the leased property? 714.5 Section 714.5 Banks and... required if you rely on an estimated residual value greater than 25% of the original cost of the leased property? If the amount of the estimated residual value you rely upon to satisfy the full payout...

  20. 21 CFR 314.122 - Submitting an abbreviated application for, or a 505(j)(2)(C) petition that relies on, a listed...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 505(j)(2)(C) petition that relies on, a listed drug that is no longer marketed. 314.122 Section 314... Abbreviated Applications § 314.122 Submitting an abbreviated application for, or a 505(j)(2)(C) petition that... to, or a petition under section 505(j)(2)(C) of the act and § 314.93 that relies on, a listed...

  1. 16 CFR Appendix to Part 1115 - Voluntary Standards on Which the Commission Has Relied Under Section 9 of the Consumer Product...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Has Relied Under Section 9 of the Consumer Product Safety Act Appendix to Part 1115 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SUBSTANTIAL PRODUCT... Relied Under Section 9 of the Consumer Product Safety Act The following are the voluntary standards...

  2. Social Plasticity Relies on Different Neuroplasticity Mechanisms across the Brain Social Decision-Making Network in Zebrafish.

    PubMed

    Teles, Magda C; Cardoso, Sara D; Oliveira, Rui F

    2016-01-01

    Social living animals need to adjust the expression of their behavior to their status within the group and to changes in social context and this ability (social plasticity) has an impact on their Darwinian fitness. At the proximate level social plasticity must rely on neuroplasticity in the brain social decision-making network (SDMN) that underlies the expression of social behavior, such that the same neural circuit may underlie the expression of different behaviors depending on social context. Here we tested this hypothesis in zebrafish by characterizing the gene expression response in the SDMN to changes in social status of a set of genes involved in different types of neural plasticity: bdnf, involved in changes in synaptic strength; npas4, involved in contextual learning and dependent establishment of GABAergic synapses; neuroligins (nlgn1 and nlgn2) as synaptogenesis markers; and genes involved in adult neurogenesis (wnt3 and neurod). Four social phenotypes were experimentally induced: Winners and Losers of a real-opponent interaction; Mirror-fighters, that fight their own image in a mirror and thus do not experience a change in social status despite the expression of aggressive behavior; and non-interacting fish, which were used as a reference group. Our results show that each social phenotype (i.e., Winners, Losers, and Mirror-fighters) present specific patterns of gene expression across the SDMN, and that different neuroplasticity genes are differentially expressed in different nodes of the network (e.g., BDNF in the dorsolateral telencephalon, which is a putative teleost homolog of the mammalian hippocampus). Winners expressed unique patterns of gene co-expression across the SDMN, whereas in Losers and Mirror-fighters the co-expression patterns were similar in the dorsal regions of the telencephalon and in the supracommissural nucleus of the ventral telencephalic area, but differents in the remaining regions of the ventral telencephalon. These results

  3. Social Plasticity Relies on Different Neuroplasticity Mechanisms across the Brain Social Decision-Making Network in Zebrafish

    PubMed Central

    Teles, Magda C.; Cardoso, Sara D.; Oliveira, Rui F.

    2016-01-01

    Social living animals need to adjust the expression of their behavior to their status within the group and to changes in social context and this ability (social plasticity) has an impact on their Darwinian fitness. At the proximate level social plasticity must rely on neuroplasticity in the brain social decision-making network (SDMN) that underlies the expression of social behavior, such that the same neural circuit may underlie the expression of different behaviors depending on social context. Here we tested this hypothesis in zebrafish by characterizing the gene expression response in the SDMN to changes in social status of a set of genes involved in different types of neural plasticity: bdnf, involved in changes in synaptic strength; npas4, involved in contextual learning and dependent establishment of GABAergic synapses; neuroligins (nlgn1 and nlgn2) as synaptogenesis markers; and genes involved in adult neurogenesis (wnt3 and neurod). Four social phenotypes were experimentally induced: Winners and Losers of a real-opponent interaction; Mirror-fighters, that fight their own image in a mirror and thus do not experience a change in social status despite the expression of aggressive behavior; and non-interacting fish, which were used as a reference group. Our results show that each social phenotype (i.e., Winners, Losers, and Mirror-fighters) present specific patterns of gene expression across the SDMN, and that different neuroplasticity genes are differentially expressed in different nodes of the network (e.g., BDNF in the dorsolateral telencephalon, which is a putative teleost homolog of the mammalian hippocampus). Winners expressed unique patterns of gene co-expression across the SDMN, whereas in Losers and Mirror-fighters the co-expression patterns were similar in the dorsal regions of the telencephalon and in the supracommissural nucleus of the ventral telencephalic area, but differents in the remaining regions of the ventral telencephalon. These results

  4. Spatial reorganization of the endoplasmic reticulum during mitosis relies on mitotic kinase cyclin A in the early Drosophila embryo.

    PubMed

    Bergman, Zane J; Mclaurin, Justin D; Eritano, Anthony S; Johnson, Brittany M; Sims, Amanda Q; Riggs, Blake

    2015-01-01

    Mitotic cyclin-dependent kinase with their cyclin partners (cyclin:Cdks) are the master regulators of cell cycle progression responsible for regulating a host of activities during mitosis. Nuclear mitotic events, including chromosome condensation and segregation have been directly linked to Cdk activity. However, the regulation and timing of cytoplasmic mitotic events by cyclin:Cdks is poorly understood. In order to examine these mitotic cytoplasmic events, we looked at the dramatic changes in the endoplasmic reticulum (ER) during mitosis in the early Drosophila embryo. The dynamic changes of the ER can be arrested in an interphase state by inhibition of either DNA or protein synthesis. Here we show that this block can be alleviated by micro-injection of Cyclin A (CycA) in which defined mitotic ER clusters gathered at the spindle poles. Conversely, micro-injection of Cyclin B (CycB) did not affect spatial reorganization of the ER, suggesting CycA possesses the ability to initiate mitotic ER events in the cytoplasm. Additionally, RNAi-mediated simultaneous inhibition of all 3 mitotic cyclins (A, B and B3) blocked spatial reorganization of the ER. Our results suggest that mitotic ER reorganization events rely on CycA and that control and timing of nuclear and cytoplasmic events during mitosis may be defined by release of CycA from the nucleus as a consequence of breakdown of the nuclear envelope.

  5. Robust intestinal homeostasis relies on cellular plasticity in enteroblasts mediated by miR-8–Escargot switch

    PubMed Central

    Antonello, Zeus A; Reiff, Tobias; Ballesta-Illan, Esther; Dominguez, Maria

    2015-01-01

    The intestinal epithelium is remarkably robust despite perturbations and demand uncertainty. Here, we investigate the basis of such robustness using novel tracing methods that allow simultaneously capturing the dynamics of stem and committed progenitor cells (called enteroblasts) and intestinal cell turnover with spatiotemporal resolution. We found that intestinal stem cells (ISCs) divide “ahead” of demand during Drosophila midgut homeostasis. Their newborn enteroblasts, on the other hand, take on a highly polarized shape, acquire invasive properties and motility. They extend long membrane protrusions that make cell–cell contact with mature cells, while exercising a capacity to delay their final differentiation until a local demand materializes. This cellular plasticity is mechanistically linked to the epithelial–mesenchymal transition (EMT) programme mediated by escargot, a snail family gene. Activation of the conserved microRNA miR-8/miR-200 in “pausing” enteroblasts in response to a local cell loss promotes timely terminal differentiation via a reverse MET by antagonizing escargot. Our findings unveil that robust intestinal renewal relies on hitherto unrecognized plasticity in enteroblasts and reveal their active role in sensing and/or responding to local demand. PMID:26077448

  6. A second mechanism for aluminum resistance in wheat relies on the constitutive efflux of citrate from roots.

    PubMed

    Ryan, Peter R; Raman, Harsh; Gupta, Sanjay; Horst, Walter J; Delhaize, Emmanuel

    2009-01-01

    The first confirmed mechanism for aluminum (Al) resistance in plants is encoded by the wheat (Triticum aestivum) gene, TaALMT1, on chromosome 4DL. TaALMT1 controls the Al-activated efflux of malate from roots, and this mechanism is widespread among Al-resistant genotypes of diverse genetic origins. This study describes a second mechanism for Al resistance in wheat that relies on citrate efflux. Citrate efflux occurred constitutively from the roots of Brazilian cultivars Carazinho, Maringa, Toropi, and Trintecinco. Examination of two populations segregating for this trait showed that citrate efflux was controlled by a single locus. Whole-genome linkage mapping using an F(2) population derived from a cross between Carazinho (citrate efflux) and the cultivar EGA-Burke (no citrate efflux) identified a major locus on chromosome 4BL, Xce(c), which accounts for more than 50% of the phenotypic variation in citrate efflux. Mendelizing the quantitative variation in citrate efflux into qualitative data, the Xce(c) locus was mapped within 6.3 cM of the microsatellite marker Xgwm495 locus. This linkage was validated in a second population of F(2:3) families derived from a cross between Carazinho and the cultivar Egret (no citrate efflux). We show that expression of an expressed sequence tag, belonging to the multidrug and toxin efflux (MATE) gene family, correlates with the citrate efflux phenotype. This study provides genetic and physiological evidence that citrate efflux is a second mechanism for Al resistance in wheat.

  7. 49 CFR 40.371 - On what information does an initiating official rely in deciding whether to start a PIE proceeding?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Public Interest Exclusions § 40.371 On what information does an initiating official rely in deciding whether...

  8. Summer kill rates and predation pattern in a wolf-moose system: can we rely on winter estimates?

    PubMed

    Sand, Håkan; Wabakken, Petter; Zimmermann, Barbara; Johansson, Orjan; Pedersen, Hans C; Liberg, Olof

    2008-05-01

    So far the vast majority of studies on large carnivore predation, including kill rates and consumption, have been based on winter studies. Because large carnivores relying on ungulates as prey often show a preference for juveniles, kill rates may be both higher and more variable during the summer season than during the rest of the year leading to serious underestimates of the total annual predation rate. This study is the first to present detailed empirical data on kill rates and prey selection in a wolf-moose system during summer (June-September) as obtained by applying modern Global Positioning System-collar techniques on individual wolves (Canis lupus) in Scandinavia. Moose (Alces alces) was the dominant prey species both by number (74.4%) and biomass (95.6%); 89.9% of all moose killed were juveniles, representing 76.0% of the biomass consumed by wolves. Kill rate in terms of the kilogram biomass/kilogram wolf per day averaged 0.20 (range: 0.07-0.32) among wolf territories and was above, or well above, the daily minimum food requirements in most territories. The average number of days between moose kills across wolf territories and study periods was 1.71 days, but increased with time and size of growing moose calves during summer. Over the entire summer (June-September, 122 days), a group (from two to nine) of wolves killed a total of 66 (confidence interval 95%; 56-81) moose. Incorporation of body growth functions of moose calves and yearlings and wolf pups over the summer period showed that wolves adjusted their kill rate on moose, so the amount of biomass/kilogram wolf was relatively constant or increased. The kill rate was much higher (94-116%) than estimated from the winter period. As a consequence, projecting winter kill rates to obtain annual estimates of predation in similar predator-prey systems may result in a significant underestimation of the total number of prey killed.

  9. Motor Learning Relies on Integrated Sensory Inputs in ADHD, but Over-Selectively on Proprioception in Autism Spectrum Conditions

    PubMed Central

    Izawa, Jun; Pekny, Sarah E; Marko, Mollie K; Haswell, Courtney C; Shadmehr, Reza; Mostofsky, Stewart H

    2012-01-01

    Lay Abstract Children with autism spectrum disorder (ASD) show deficits in development of motor skills, in addition to core deficits in social skill development. In a previous study (Haswell et al., 2009) we found that children with autism show a key difference in how they learn motor actions, with a bias for relying on joint position rather than visual feedback; further, this pattern of motor learning predicted impaired motor, imitation and social abilities. We were interested in finding out whether this altered motor learning pattern was specific to autism. To do so, we examined children with Attention Deficit Hyperactivity Disorder (ADHD), who also show deficits in motor control. Children learned a novel movement and we measured rates of motor learning, generalization patterns of motor learning, and variability of motor speed during learning. We found children with ASD show a slower rate of learning and, consistent with previous findings, an altered pattern of generalization that was predictive of impaired motor, imitation, and social impairment. In contrast, children with ADHD showed a normal rate of learning and a normal pattern of generalization; instead, they (and they alone), showed excessive variability in movement speed. The findings suggest that there is a specific pattern of altered motor learning associated with autism. Scientific Abstract The brain builds an association between action and sensory feedback to predict the sensory consequence of self-generated motor commands. This internal model of action is central to our ability to adapt movements, and may also play a role in our ability to learn from observing others. Recently we reported that the spatial generalization patterns that accompany adaptation of reaching movements were distinct in children with Autism Spectrum Disorder (ASD) as compared to typically developing (TD) children. To test whether the generalization patterns are specific to ASD, here we compared the patterns of adaptation to

  10. 17 CFR 270.12d1-2 - Exemptions for investment companies relying on section 12(d)(1)(G) of the Act.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... companies relying on section 12(d)(1)(G) of the Act. 270.12d1-2 Section 270.12d1-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.12d1-2 Exemptions for investment companies relying on section 12(d)(1)(G) of the Act....

  11. Research Advances: Pacific Northwest National Laboratory Finds New Way to Detect Destructive Enzyme Activity--Hair Dye Relies on Nanotechnology--Ways to Increase Shelf Life of Milk

    ERIC Educational Resources Information Center

    King, Angela G.

    2007-01-01

    Recent advances in various research fields are described. Scientists at the Pacific Northwest National Laboratory have found a new way to detect destructive enzyme activity, scientists in France have found that an ancient hair dye used by ancient people in Greece and Rome relied on nanotechnology and in the U.S. scientists are developing new…

  12. Cytotoxicity Comparison of Harvard Zinc Phosphate Cement Versus Panavia F2 and Rely X Plus Resin Cements on Rat L929-fibroblasts

    PubMed Central

    Mahasti, Sahabi; Sattari, Mandana; Romoozi, Elham; Akbar-zadeh Baghban, Alireza

    2011-01-01

    Objective: Resin cements, regardless of their biocompatibility, have been widely used in restorative dentistry during the recent years. These cements contain hydroxy ethyl methacrylate (HEMA) molecules which are claimed to penetrate into dentinal tubules and may affect dental pulp. Since tooth preparation for metal ceramic restorations involves a large surface of the tooth, cytotoxicity of these cements would be more important in fixed prosthodontic treatments. The purpose of this study was to compare the cytotoxicity of two resin cements (Panavia F2 and Rely X Plus) versus zinc phosphate cement (Harvard) using rat L929-fibroblasts in vitro. Materials and Methods: In this experimental study, ninety hollow glass cylinders (internal diameter 5-mm, height 2-mm) were made and divided into three groups. Each group was filled with one of three experimental cements; Harvard Zinc Phosphate cement, Panavia F2 resin cement and Rely X Plus resin cement. L929- Fibroblast were passaged and subsequently cultured in 6-well plates of 5×105 cells each. The culture medium was RPMI_ 1640. All samples were incubated in CO2. Using enzyme-linked immune-sorbent assay (ELISA) and (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) (MTT) assay, the cytotoxicity of the cements was investigated at 1 hour, 24 hours and one week post exposure. Statistical analyses were performed via two-way ANOVA and honestly significant difference (HSD) Tukey tests. Results: This study revealed significant differences between the three cements at the different time intervals. Harvard cement displayed the greatest cytotoxicity at all three intervals. After 1 hour Panavia F2 showed the next greatest cytotoxicity, but after 24-hours and oneweek intervals Rely X Plus showed the next greatest cytotoxicity. The results further showed that cytotoxicity decreased significantly in the Panavia F2 group with time (p<0.005), cytotoxicity increased significantly in the Rely X Plus group with time (p<0

  13. Comparison of Characteristics and Outcomes of Dabigatran Versus Warfarin in Hypertensive Patients With Atrial Fibrillation (from the RE-LY Trial).

    PubMed

    Nagarakanti, Rangadham; Wallentin, Lars; Noack, Herbert; Brueckmann, Martina; Reilly, Paul; Clemens, Andreas; Connolly, Stuart J; Yusuf, Salim; Ezekowitz, Michael D

    2015-10-15

    Hypertension is frequent in patients with atrial fibrillation (AF) and is an independent risk factor for stroke. The Randomized Evaluation of Long Term Anticoagulant TherapY (RE-LY) trial found dabigatran 110 mg (D110) and 150 mg twice daily (D150) noninferior or superior to warfarin for stroke reduction in patients with AF, with either a reduction (D110) or similar rates (D150) of major bleeding. Baseline characteristics and outcomes were compared in patients with and without hypertension. The quality of blood pressure control was also assessed. In RE-LY, 14,283 patients (78.9%) had hypertension. The mean blood pressure at baseline was 132.6 ± 17.6/77.7 ± 10.6 and 124.8 ± 16.7/74.6 ± 10.0 mm Hg for patients with and without hypertension, respectively. More patients with hypertension were diabetic (25.6% vs 14.8%, p <0.001), women (38.6% vs 28.3%, p <0.001), and had greater CHADS2 (2.3 vs 1.4, p <0.001) and CHA2DS2-VASc scores (3.8 vs 2.8, p <0.001). Mean blood pressure in all treatment arms in hypertensive patients was similar (130 ± 18/76 ± 11 mm Hg) during the trial. The efficacy and safety of D110 and D150 compared to warfarin were similar (p = nonsignificant) in hypertensive (stroke/systemic embolism rate of 1.47%, 1.20%, and 1.81% and major bleed rate of 2.89%, 3.70%, and 3.69% in the D110, D150, and W, respectively) and normotensive patients (stroke/systemic embolism rate of 1.79%, 0.78%, and 1.36% and major bleed rate of 2.84%, 2.37%, and 3.03% per year in the D110, D150, and W, respectively). Hypertensive patients had more major bleeds (3.39% vs 2.76%; p = 0.007). Intracranial bleeds were similar (0.47% vs 0.31%; p = 0.12). In conclusion, patients with hypertension in RE-LY were more likely female, diabetic, with a greater CHADS2 and CHA2DS2-VASc scores. Blood pressure control in RE-LY was excellent. The benefits of dabigatran over warfarin, including a substantial reduction of intracranial hemorrhage, were similar in both hypertensive

  14. Trois inconnues qui bouleversent le Big Bang

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    2002-10-01

    Deux coups de tonnerre gigantesques dans le ciel de la cosmologie ont très récemment chamboulé notre vision de l'univers. Avec l'apparition d'une mystérieuse énergie sombre et la confirmation de la platitude de l'Univers, toutes les théories sur son évolution sont à revoir. Aujourd'hui l'Univers n'a plus de visage et tout est à reconstruire. Retour sur une histoire à rebondissements.

  15. Les etoiles qui ne veulent pas vieillir

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1996-02-01

    Les astronomes les ont baptisees "trainardes bleues", blue stragglers en anglais. Ces etoiles a l'apparence tres ordinaire se rencontrent un peu partout dans la Galaxie. Elles sont chaudes et bleues, signe evident de jeunesse dans leur monde. C'est bien le paradoxe car les "blue stragglers" trichent sur leur age, comme si elles refusaient d'evoluer, laissant les astronomes dans la plus grande perplexite.

  16. [Diagnosis of the territories with the use of integral indices of chemical contamination of soil and grounds, relied on the background and hygienic standards].

    PubMed

    Bogdanov, N A

    2014-01-01

    Analysis of the efficiency of diagnosis of lands for different functional appropriations with integral indices of chemical contamination of soils and grounds under different environmental conditions showed: the greatest accuracy of the information about the structure and degree of contamination of territories is provided by the index relying on hygienic standard (index of soil contamination, ISC). The number of hygienically dangerous lithochemical anomalies revealed by ISC is several times more than the fixed by the index of total pollution of soils by trace elements (Zc), focused only on their background levels. Index Zc is in many respects subjective and unacceptable in complex soil geochemical conditions where the selection of the regional background is impossible. ISC account not only in trace elements, but other hygienically regulated substances (As, Hg, mobile forms of metals, water-soluble salts, carbohydrates, etc.) either. PMID:24749294

  17. Perioperative bridging anticoagulation during dabigatran or warfarin interruption among patients who had an elective surgery or procedure. Substudy of the RE-LY trial.

    PubMed

    Douketis, James D; Healey, Jeff S; Brueckmann, Martina; Eikelboom, John W; Ezekowitz, Michael D; Fraessdorf, Mandy; Noack, Herbert; Oldgren, Jonas; Reilly, Paul; Spyropoulos, Alex C; Wallentin, Lars; Connolly, Stuart J

    2015-03-01

    In patients with atrial fibrillation (AF) who require interruption of dabigatran or warfarin for an elective surgery/procedure, the risks and benefits of perioperative bridging anticoagulation is uncertain.We accessed the database from RE-LY, a randomised trial comparing dabigatran with warfarin for stroke prevention in AF, to assess the potential benefits and risks of bridging. In patients who had a first interruption of dabigatran or warfarin for an elective surgery/procedure, we compared the risk for major bleeding (MB), stroke or systemic embolism (SSE) and any thromboembolism (TE) in patients who were bridged or not bridged during the period of seven days before until 30 days after surgery/procedure. We used multivariable Cox regression to adjust for potential confounders.Bridging was used more during warfarin interruption than dabigatran interruption (27.5 % vs 15.4 %; p< 0.001). With dabigatran interruption, bridged patients had more MB (6.5 % vs 1.8 %, p< 0.001) than those not bridged but bridged and not bridged groups did not differ for any TE (1.2 % vs 0.6 %, p=0.16) and SSE (0.5 % vs 0.3 %, p=0.46). With warfarin interruption, bridged patients had more MB (6.8 % vs 1.6 %, p< 0.001) and any TE (1.8 % vs 0.3 %, p=0.007) than those not bridged but bridged and not bridged groups did not differ for SSE (0.5 % vs 0.2 %, p=0.321). In conclusion, in patients who interrupted dabigatran or warfarin for a surgery/ procedure in the RE-LY trial, use of bridging anticoagulation appeared to increase the risk for major bleeding irrespective of dabigatran or warfarin interruption.

  18. Influence of secreted frizzled receptor protein 1 (SFRP1) on neoadjuvant chemotherapy in triple negative breast cancer does not rely on WNT signaling

    PubMed Central

    2014-01-01

    Background Triple negative breast cancer (TNBC) is characterized by lack of expression of both estrogen and progesterone receptor as well as lack of overexpression or amplification of HER2. Despite an increased probability of response to chemotherapy, many patients resistant to current chemotherapy regimens suffer from a worse prognosis compared to other breast cancer subtypes. However, molecular determinants of response to chemotherapy specific to TNBC remain largely unknown. Thus, there is a high demand for biomarkers potentially stratifying triple negative breast cancer patients for neoadjuvant chemotherapies or alternative therapies. Methods In order to identify genes correlating with both the triple negative breast cancer subtype as well as response to neoadjuvant chemotherapy we employed publicly available gene expression profiles of patients, which had received neoadjuvant chemotherapy. Analysis of tissue microarrays as well as breast cancer cell lines revealed correlation to the triple negative breast cancer subtype. Subsequently, effects of siRNA-mediated knockdown on response to standard chemotherapeutic agents as well as radiation therapy were analyzed. Additionally, we evaluated the molecular mechanisms by which SFRP1 alters the carcinogenic properties of breast cancer cells. Results SFRP1 was identified as being significantly overexpressed in TNBC compared to other breast cancer subtypes. Additionally, SFRP1 expression is significantly correlated with an increased probability of positive response to neoadjuvant chemotherapy. Knockdown of SFRP1 in triple negative breast cancer cells renders the cells more resistant to standard chemotherapy. Moreover, tumorigenic properties of the cells are modified by knockdown, as shown by both migration or invasion capacity as well reduced apoptotic events. Surprisingly, we found that these effects do not rely on Wnt signaling. Furthermore, we show that pro-apoptotic as well as migratory pathways are differentially

  19. Can grass phytoliths and indices be relied on during vegetation and climate interpretations in the eastern Himalayas? Studies from Darjeeling and Arunachal Pradesh, India

    NASA Astrophysics Data System (ADS)

    Biswas, Oindrila; Ghosh, Ruby; Paruya, Dipak Kumar; Mukherjee, Biswajit; Thapa, Kishore Kumar; Bera, Subir

    2016-02-01

    While documenting the vegetation response to climatic changes in mountains, the use of grass phytolith data relies on the ability of phytolith assemblages or indices to differentiate the elevationally stratified vegetation zones. To infer the potential and limitations of grass phytolith assemblages and indices to reconstruct vegetation vis-à-vis climate in the Himalayan mountain regions, we analyzed phytolith assemblages from 66 dominant grasses and 153 surface soils from four different forest types along the c. 130-4000 m a.s.l. elevation gradients in the Darjeeling and Arunachal Himalayas. Grass short cell phytolith assemblages from modern grasses show significant variability with rising elevation. To test the reliability of the above observation, phytoliths from the soil samples were subjected to linear discriminant analysis (DA). DA classified 85.3% and 92.3% of the sites to their correct forest zones in the Darjeeling and Arunachal Himalayas respectively. Relative abundance of bilobate, cross, short saddle, plateau saddle, rondel and trapeziform types allow discrimination of the phytolith assemblage along the elevation gradient. Canonical correspondence analysis (CCA) on the soil phytolith data further revealed their relationships with the climatic variables. Temperature and evapotranspiration were found to be the most influential for differential distribution of grass phytolith assemblages with rising elevation in the eastern Himalayas. We also tested the reliability of phytolith indices (Ic, Iph and Fs) for tracing the dominance of different grass subfamilies in the eastern Himalayas. Ic proved to be most reliable in discriminating C3/C4 grass along the elevation gradient while Iph and Fs proved to be less reliable. We observed that in the monsoon dominated eastern Himalayas, a little adjustment in Ic index may enhance the accuracy of interpretations. In future studies more precise identification of phytolith sub-types from additional sites in the eastern

  20. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing

    PubMed Central

    McCue, Marshall D.; Guzman, R. Marena; Passement, Celeste A.; Davidowitz, Goggy

    2015-01-01

    Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation. PMID:26465334

  1. Cytosolic NADPH homeostasis in glucose-starved procyclic Trypanosoma brucei relies on malic enzyme and the pentose phosphate pathway fed by gluconeogenic flux.

    PubMed

    Allmann, Stefan; Morand, Pauline; Ebikeme, Charles; Gales, Lara; Biran, Marc; Hubert, Jane; Brennand, Ana; Mazet, Muriel; Franconi, Jean-Michel; Michels, Paul A M; Portais, Jean-Charles; Boshart, Michael; Bringaud, Frédéric

    2013-06-21

    All living organisms depend on NADPH production to feed essential biosyntheses and for oxidative stress defense. Protozoan parasites such as the sleeping sickness pathogen Trypanosoma brucei adapt to different host environments, carbon sources, and oxidative stresses during their infectious life cycle. The procyclic stage develops in the midgut of the tsetse insect vector, where they rely on proline as carbon source, although they prefer glucose when grown in rich media. Here, we investigate the flexible and carbon source-dependent use of NADPH synthesis pathways in the cytosol of the procyclic stage. The T. brucei genome encodes two cytosolic NADPH-producing pathways, the pentose phosphate pathway (PPP) and the NADP-dependent malic enzyme (MEc). Reverse genetic blocking of those pathways and a specific inhibitor (dehydroepiandrosterone) of glucose-6-phosphate dehydrogenase together established redundancy with respect to H2O2 stress management and parasite growth. Blocking both pathways resulted in ∼10-fold increase of susceptibility to H2O2 stress and cell death. Unexpectedly, the same pathway redundancy was observed in glucose-rich and glucose-depleted conditions, suggesting that gluconeogenesis can feed the PPP to provide NADPH. This was confirmed by (i) a lethal phenotype of RNAi-mediated depletion of glucose-6-phosphate isomerase (PGI) in the glucose-depleted Δmec/Δmec null background, (ii) an ∼10-fold increase of susceptibility to H2O2 stress observed for the Δmec/Δmec/(RNAi)PGI double mutant when compared with the single mutants, and (iii) the (13)C enrichment of glycolytic and PPP intermediates from cells incubated with [U-(13)C]proline, in the absence of glucose. Gluconeogenesis-supported NADPH supply may also be important for nucleotide and glycoconjugate syntheses in the insect host.

  2. Synthesis and structure determination of seven ternary bismuthides: crystal chemistry of the RELi3Bi2 family (RE = La-Nd, Sm, Gd, and Tb).

    PubMed

    Prakash, Jai; Schäfer, Marion C; Bobev, Svilen

    2015-10-01

    Zintl phases are renowned for their diverse crystal structures with rich structural chemistry and have recently exhibited some remarkable heat- and charge-transport properties. The ternary bismuthides RELi3Bi2 (RE = La-Nd, Sm, Gd, and Tb) (namely, lanthanum trilithium dibismuthide, LaLi3Bi2, cerium trilithium dibismuthide, CeLi3Bi2, praseodymium trilithium dibismuthide, PrLi3Bi2, neodymium trilithium dibismuthide, NdLi3Bi2, samarium trilithium dibismuthide, SmLi3Bi2, gadolinium trilithium dibismuthide, GdLi3Bi2, and terbium trilithium dibismuthide, TbLi3Bi2) were synthesized by high-temperature reactions of the elements in sealed Nb ampoules. Single-crystal X-ray diffraction analysis shows that all seven compounds are isostructural and crystallize in the LaLi3Sb2 type structure in the trigonal space group P-3m1 (Pearson symbol hP6). The unit-cell volumes decrease monotonically on moving from the La to the Tb compound, owing to the lanthanide contraction. The structure features a rare-earth metal atom and one Li atom in a nearly perfect octahedral coordination by six Bi atoms. The second crystallographically unique Li atom is surrounded by four Bi atoms in a slightly distorted tetrahedral geometry. The atomic arrangements are best described as layered structures consisting of two-dimensional layers of fused LiBi4 tetrahedra and LiBi6 octahedra, separated by rare-earth metal cations. As such, these compounds are expected to be valance-precise semiconductors, whose formulae can be represented as (RE(3+))(Li(1+))3(Bi(3-))2.

  3. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

    PubMed

    McCue, Marshall D; Guzman, R Marena; Passement, Celeste A; Davidowitz, Goggy

    2015-01-01

    Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation. PMID:26465334

  4. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

    PubMed

    McCue, Marshall D; Guzman, R Marena; Passement, Celeste A; Davidowitz, Goggy

    2015-01-01

    Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.

  5. Audiovisual speech integration does not rely on the motor system: evidence from articulatory suppression, the McGurk effect, and fMRI.

    PubMed

    Matchin, William; Groulx, Kier; Hickok, Gregory

    2014-03-01

    Visual speech influences the perception of heard speech. A classic example of this is the McGurk effect, whereby an auditory /pa/ overlaid onto a visual /ka/ induces the fusion percept of /ta/. Recent behavioral and neuroimaging research has highlighted the importance of both articulatory representations and motor speech regions of the brain, particularly Broca's area, in audiovisual (AV) speech integration. Alternatively, AV speech integration may be accomplished by the sensory system through multisensory integration in the posterior STS. We assessed the claims regarding the involvement of the motor system in AV integration in two experiments: (i) examining the effect of articulatory suppression on the McGurk effect and (ii) determining if motor speech regions show an AV integration profile. The hypothesis regarding experiment (i) is that if the motor system plays a role in McGurk fusion, distracting the motor system through articulatory suppression should result in a reduction of McGurk fusion. The results of experiment (i) showed that articulatory suppression results in no such reduction, suggesting that the motor system is not responsible for the McGurk effect. The hypothesis of experiment (ii) was that if the brain activation to AV speech in motor regions (such as Broca's area) reflects AV integration, the profile of activity should reflect AV integration: AV > AO (auditory only) and AV > VO (visual only). The results of experiment (ii) demonstrate that motor speech regions do not show this integration profile, whereas the posterior STS does. Instead, activity in motor regions is task dependent. The combined results suggest that AV speech integration does not rely on the motor system.

  6. D-dimer and factor VIIa in atrial fibrillation - prognostic values for cardiovascular events and effects of anticoagulation therapy. A RE-LY substudy.

    PubMed

    Siegbahn, Agneta; Oldgren, Jonas; Andersson, Ulrika; Ezekowitz, Michael D; Reilly, Paul A; Connolly, Stuart J; Yusuf, Salim; Wallentin, Lars; Eikelboom, John W

    2016-05-01

    Coagulation markers may improve monitoring the risk of stroke and bleeding in patients with atrial fibrillation (AF) during anticoagulant treatment. We examined baseline levels of D-dimer and their association with stroke, cardiovascular death and major bleeding in 6,202 AF patients randomised to dabigatran or warfarin in the RE-LY trial. The effects of treatment on serial levels of D-dimer and coagulation factor (F) VIIa in 2,567 patients were also analysed. Baseline D-dimer levels were related to the rate of stroke/systemic embolism (SEE) with 0.64 % in the lowest quartile (Q1, as reference) (D-dimer < 298 µg/l), 1.38 % Q2 (D-dimer 298-473 µg/l), 1.71 % Q3 (D-dimer 474-822 µg/l) and 2.00 % in Q4 (D-dimer > 822 µg/l) (p=0.0007). Similar associations were shown for cardiovascular death and major bleeding. Addition of baseline D-dimer to established clinical risk factors improved prediction of stroke/SEE, cardiovascular death and major bleeding (C-index increased from 0.66 to 0.68, 0.71 to 0.73 and 0.66 to 0.67, respectively). Dabigatran provided a greater reduction of D-dimer levels than warfarin regardless of baseline anticoagulant treatment. On-treatment levels of FVIIa were markedly reduced by warfarin (median 12.1-13.8 mU/ml) but significantly higher with dabigatran (median 39.4-49.0 mU/ml) at all-time points. Dabigatran is associated with greater reduction in D-dimer without the pronounced reduction of FVIIa seen with warfarin. These different effects on the coagulation system might explain the better efficacy and less intracranial bleeding observed with dabigatran compared with warfarin.

  7. Synthesis and structure determination of seven ternary bismuthides: crystal chemistry of the RELi3Bi2 family (RE = La-Nd, Sm, Gd, and Tb).

    PubMed

    Prakash, Jai; Schäfer, Marion C; Bobev, Svilen

    2015-10-01

    Zintl phases are renowned for their diverse crystal structures with rich structural chemistry and have recently exhibited some remarkable heat- and charge-transport properties. The ternary bismuthides RELi3Bi2 (RE = La-Nd, Sm, Gd, and Tb) (namely, lanthanum trilithium dibismuthide, LaLi3Bi2, cerium trilithium dibismuthide, CeLi3Bi2, praseodymium trilithium dibismuthide, PrLi3Bi2, neodymium trilithium dibismuthide, NdLi3Bi2, samarium trilithium dibismuthide, SmLi3Bi2, gadolinium trilithium dibismuthide, GdLi3Bi2, and terbium trilithium dibismuthide, TbLi3Bi2) were synthesized by high-temperature reactions of the elements in sealed Nb ampoules. Single-crystal X-ray diffraction analysis shows that all seven compounds are isostructural and crystallize in the LaLi3Sb2 type structure in the trigonal space group P-3m1 (Pearson symbol hP6). The unit-cell volumes decrease monotonically on moving from the La to the Tb compound, owing to the lanthanide contraction. The structure features a rare-earth metal atom and one Li atom in a nearly perfect octahedral coordination by six Bi atoms. The second crystallographically unique Li atom is surrounded by four Bi atoms in a slightly distorted tetrahedral geometry. The atomic arrangements are best described as layered structures consisting of two-dimensional layers of fused LiBi4 tetrahedra and LiBi6 octahedra, separated by rare-earth metal cations. As such, these compounds are expected to be valance-precise semiconductors, whose formulae can be represented as (RE(3+))(Li(1+))3(Bi(3-))2. PMID:26422218

  8. Activation of procathepsin B in human hepatoma cells: the conversion into the mature enzyme relies on the action of cathepsin B itself.

    PubMed Central

    Mach, L; Schwihla, H; Stüwe, K; Rowan, A D; Mort, J S; Glössl, J

    1993-01-01

    In order to elucidate the processing mechanism of the lysosomal cysteine proteinase, cathepsin B, in mammalian cells, recombinant rat and human cathepsin B precursors were expressed in Saccharomyces cerevisiae. The active-site cysteine residue was changed to serine to prevent autoprocessing. When the purified proenzymes were incubated with the soluble fraction of postnuclear organelles obtained from human hepatoma HepG2 cells, processing to a 33 kDa form corresponding to the mature endogenous single-chain enzyme was observed. Inhibitors of metallo-, serine and aspartic proteinases exerted no significant effect on procathepsin B processing in vitro. However, the processing activity was effectively blocked by cysteine proteinase inhibitors, in particular E-64 and its cathepsin-B-selective derivative CA-074. Processing positions were identified by using anti-peptide antibodies specific for epitopes in the N- and C-terminal cleavage regions. The single-chain form produced in vitro was thus shown to contain an N-terminal extension of at least four residues relative to the mature lysosomal enzyme, as well as a C-terminal extension present in the proenzyme but usually absent in fully processed cathepsin B. On expression of the wild-type proenzyme in yeast, procathepsin B undergoes autoprocessing, yielding a single-chain form of the active enzyme, which contains similar N- and C-terminal extensions. These results indicate that maturation of procathepsin B in vivo in mammalian tissues relies on the proteolytic activity of cathepsin B itself. Images Scheme 1 Figure 1 Figure 2 Figure 3 Figure 4 PMID:8393661

  9. [Analysis of EDS fingerprint spectra of mineral drug montmorillonite powder relying on dual index grade sequence individualized pattern recognition method and their quickly quality evaluation].

    PubMed

    Zou, Hua-Bin; Ayiguzaili; Ablimiti; Zhai, Hong

    2013-12-01

    EDS(energy dispersive spectrometer) element fingerprint spectra is able to quickly measure the kinds and the contents of elements in any mineral drug. In dual index grade sequence individualized pattern recognition method, common (quantity) index and variation (quantity) index ratios of any two samples' fingerprint spectra are calculated, and the individualized dual index sequence of each sample is constructed relying on its own EDS fingerprint spectra as the reference. Then the mean common (quantity) index ratio P and the standard deviation S of all samples in each sample's individualized dual index sequence are computed. On this basis, for each sample, its own similarity scale function P> or =P+xS is built up. By this function, the optimum x suitable for optimized classification/cluster of all samples is determined, and the individualized characteristics sequence of one sample, to which samples in the individualized characteristics sequence are significantly similar, is decided also. Finally, depending on these individualized characteristics sequences, the optimized classification/cluster of all samples can be carried out perfectly without any prior knowledge related to them. This method is not only suitable for the quantitative analysis on fingerprint spectra being of only common peaks, but also fits for that being of both common and variant peaks. In this study, the EDS element fingerprint spectra of seven mineral drug montmorillonite powder samples from different companies were detected. Then common (quantity) index and variant (quantity) index ratios of peak area (or contents of majorly active element Fe, Al, Ca, Mg, Si) among different EDS fingerprint spectra were obtained. In the similarity scale function P> or =P+xS, when x= 0. 5, these seven mineral drug montmorillonite powder samples could be quickly identified with high resolution, be classified into two groups, and their quality could be evaluated precisely. In general EDS element fingerprint spectra

  10. An optimized single chain TCR scaffold relying on the assembly with the native CD3-complex prevents residual mispairing with endogenous TCRs in human T-cells

    PubMed Central

    Knies, Diana; Klobuch, Sebastian; Xue, Shao-An; Birtel, Matthias; Echchannaoui, Hakim; Yildiz, Oezlem; Omokoko, Tana; Guillaume, Philippe; Romero, Pedro; Stauss, Hans; Sahin, Ugur; Herr, Wolfgang; Theobald, Matthias; Thomas, Simone; Voss, Ralf-Holger

    2016-01-01

    Immunotherapy of cancer envisions the adoptive transfer of T-cells genetically engineered with tumor-specific heterodimeric α/β T-cell receptors (TCRα/β). However, potential mispairing of introduced TCRα/β-chains with endogenous β/α-ones may evoke unpredictable autoimmune reactivities. A novel single chain (sc)TCR format relies on the fusion of the Vα-Linker-Vβ-fragment to the TCR Cβ-domain and coexpression of the TCR Cα-domain capable of recruiting the natural CD3-complex for full and hence, native T-cell signaling. Here, we tested whether such a gp100(280-288)- or p53(264-272) tumor antigen-specific scTCR is still prone to mispairing with TCRα. In a human Jurkat-76 T-cell line lacking endogenous TCRs, surface expression and function of a scTCR could be reconstituted by any cointroduced TCRα-chain indicating mispairing to take place on a molecular basis. In contrast, transduction into human TCRα/β-positive T-cells revealed that mispairing is largely reduced. Competition experiments in Jurkat-76 confirmed the preference of dcTCR to selfpair and to spare scTCR. This also allowed for the generation of dc/scTCR-modified cytomegalovirus/tumor antigen-bispecific T-cells to augment T-cell activation in CMV-infected tumor patients. Residual mispairing was prevented by strenghtening the Vα-Li-Vβ-fragment through the design of a novel disulfide bond between a Vα- and a linker-resident residue close to Vβ. Multimer-stainings, and cytotoxicity-, IFNγ-secretion-, and CFSE-proliferation-assays, the latter towards dendritic cells endogenously processing RNA-electroporated gp100 antigen proved the absence of hybrid scTCR/TCRα-formation without impairing avidity of scTCR/Cα in T-cells. Moreover, a fragile cytomegalovirus pp65(495-503)-specific scTCR modified this way acquired enhanced cytotoxicity. Thus, optimized scTCR/Cα inhibits residual TCR mispairing to accomplish safe adoptive immunotherapy for bulk endogenous TCRα/β-positive T-cells. PMID:27028870

  11. Biological adhesion of the flatworm Macrostomum lignano relies on a duo-gland system and is mediated by a cell type-specific intermediate filament protein

    PubMed Central

    2014-01-01

    Background Free-living flatworms, in both marine and freshwater environments, are able to adhere to and release from a substrate several times within a second. This reversible adhesion relies on adhesive organs comprised of three cell types: an adhesive gland cell, a releasing gland cell, and an anchor cell, which is a modified epidermal cell responsible for structural support. However, nothing is currently known about the molecules that are involved in this adhesion process. Results In this study we present the detailed morphology of the adhesive organs of the free-living marine flatworm Macrostomum lignano. About 130 adhesive organs are located in a horse-shoe-shaped arc along the ventral side of the tail plate. Each organ consists of exactly three cells, an adhesive gland cell, a releasing gland cell, and an anchor cell. The necks of the two gland cells penetrate the anchor cell through a common pore. Modified microvilli of the anchor cell form a collar surrounding the necks of the adhesive- and releasing glands, jointly forming the papilla, the outer visible part of the adhesive organs. Next, we identified an intermediate filament (IF) gene, macif1, which is expressed in the anchor cells. RNA interference mediated knock-down resulted in the first experimentally induced non-adhesion phenotype in any marine animal. Specifically, the absence of intermediate filaments in the anchor cells led to papillae with open tips, a reduction of the cytoskeleton network, a decline in hemidesmosomal connections, and to shortened microvilli containing less actin. Conclusion Our findings reveal an elaborate biological adhesion system in a free-living flatworm, which permits impressively rapid temporary adhesion-release performance in the marine environment. We demonstrate that the structural integrity of the supportive cell, the anchor cell, is essential for this adhesion process: the knock-down of the anchor cell-specific intermediate filament gene resulted in the inability of

  12. Controlled, prospective, randomized, clinical evaluation of partial ceramic crowns inserted with RelyX Unicem with or without selective enamel etching. Results after 2 years.

    PubMed

    Schenke, Frederike; Federlin, Marianne; Hiller, Karl-Anton; Moder, Daniel; Schmalz, Gottfried

    2012-04-01

    Among the materials used for luting indirect restorations, growing interest has been directed towards the use of self-adhesive resin cements. The aim of this prospective randomized controlled clinical trial was to evaluate the clinical performance of the self-adhesive resin cement RelyX Unicem (RXU) for luting partial ceramic crowns (PCCs). In addition, the influence of selective enamel etching prior to luting (RXU+E) was assessed. Two-year results are reported. Thirty-four patients (68 PCCs) had originally received the intended treatment at baseline (BL). Twenty-nine patients (14 male, 15 female) with a total of 58 PCCs participated in the 2-year recall. In each patient, one PCC had been placed with RXU, one PCC with RXU+E. Restorations were evaluated at BL and 24 months after placement using modified United States Public Health Service criteria for postoperative hypersensitivity, anatomic form, marginal adaptation, marginal discoloration, surface texture and recurrent caries. Additionally, the "percentage failure" within the 2-year recall period for all restorations (n = 68) was calculated according to ADA Program Guidelines. Target value for acceptability of each procedure was <5% failure within 24 m. For statistical analysis of the data, the chi-square test was applied (α = 0.05). The median patient age was 41 years (24-59 years). Median PBI was 8% (5-10%). Twenty-two RXU PCCs were placed in molars, seven in premolars. Twenty-one RXU+E PCCs were placed in molars, eight in premolars. Statistically significant changes were observed for marginal adaptation (MA) and marginal discoloration (MD) between BL and 2 years but not between the two groups (RXU, RXU+E). Percentage of alfa values at BL for MA (RXU, 97% and RXU+E, 100%) and for MD (RXU, 97% and RXU+E, 97%) decreased to RXU, 14% and RXU+E, 28% for MA and to RXU, 50% and RXU+E, 59% for MD after 24 months. Within the observation period, three failures were recorded with RXU (5.1% failure), one

  13. Mathematical Ability Relies on Knowledge, Too

    ERIC Educational Resources Information Center

    Sweller, John; Clark, Richard E.; Kirschner, Paul A.

    2011-01-01

    Recent "reform" curricula both ignore the absence of supporting data and completely misunderstand the role of problem solving in cognition. If, the argument goes, teachers are not really teaching people mathematics but rather are teaching them some form of general problem solving, then mathematical content can be reduced in importance. According…

  14. The RELi{sub x}Sn{sub 2} (RE=La–Nd, Sm, and Gd; 0≤x<1) series revisited. Synthesis, crystal chemistry, and magnetic susceptibilities

    SciTech Connect

    Makongo, Julien P.A.; Suen, Nian-Tzu; Guo, Shengping; Saha, Shanta; Greene, Richard; Paglione, Johnpierre; Bobev, Svilen

    2014-03-15

    This study is concerned with the ternary compounds RELi{sub x}Sn{sub 2} (RE=La–Nd, Sm, and Gd; 0≤x<1), which have been previously thought to be the stoichiometric RELiSn{sub 2} phases. These materials crystallize with the base-centered orthorhombic space group Cmcm (No. 63), and can be formally assigned with the CeNiSi{sub 2} structure type (Pearson symbol oC16). Our systematic single-crystal X-ray diffraction studies revealed substantial Li-deficiencies in all cases, with SmSn{sub 2} (space group Cmmm, ZrGa{sub 2} structure type, Pearson symbol oC12) and GdSn{sub 2} (space group Cmcm, ZrSi{sub 2} structure type, Pearson symbol oC12) being completely lithium-free. The structure refinements also uncovered positional disorder on the Sn site neighboring the vacancies. The Sn-disorder and the Li-deficiency correlate, and vary monotonically with the decreased size of the rare-earth atoms in the order RE=La–Nd. The SmSn{sub 2} and GdSn{sub 2} structures are devoid of any disorder. Temperature-dependent studies of the magnetic response of the title compounds are also presented and discussed. -- Graphical abstract: RELi{sub x}Sn{sub 2} (RE=La–Nd, 0≤x<1) crystallize in a defect variants of the CeNiSi{sub 2} structure type (a). The Sn-disorder and the Li-deficiency correlate, and vary monotonically with the decreased size of the rare-earth atoms in the order RE=La–Nd. The SmSn{sub 2} (b) and GdSn{sub 2} (c) structures are devoid of any disorder. Highlights: • The crystal structures of the RELi{sub x}Sn{sub 2} (RE=La–Nd, 0≤x<1) compounds are revised using single-crystal X-ray diffraction data. • The structure is a filled derivative of the ZrSi{sub 2} structure type or defect variant of the CeNiSi{sub 2} structure type. • SmSn{sub 2} is isotypic with the ZrGa{sub 2} structure, while RESn{sub 2} (RE=Gd–Lu) are isotypic with the ZrSi{sub 2} structure.

  15. Does the Spatial Distribution of the Parasitic Mite Varroa jacobsoni Oud. (Mesostigmata: Varroidae) in Worker Brood of Honey Bee Apis Mellifera L. (Hymenoptera: Apidae) Rely on an Aggregative Process?

    NASA Astrophysics Data System (ADS)

    Salvy, M.; Capowiez, Y.; Le Conte, Y.; Salvy, M.; Clément, J.-L.

    Varroa jacobsoni is an ectoparasite of honey bees which reproduces in capped brood cells. Multi-infestation is frequently observed in worker brood and can be interpreted as an aggregative phenomenon. The aim of this study was to determine whether the distribution of V. jacobsoni in worker brood cells relies on a random or an aggregative process. We studied the distribution of Varroa females in capped worker brood at similar age by comparing, by a Monte Carlo test, the observed frequency distribution of mites per cell to simulated distributions based on a random process. A complementary approach, using the "nearest neighbor distances" (NND) with Monte Carlo tests, was investigated to study the spatial distribution (a) between mites in different cells and (b) between infested cells in brood. The observed distributions did not differ significantly from that expected by a random process, and we conclude that there is no aggregation during invasion of V. jacobsoni in worker brood.

  16. Spatial imagery relies on a sensory independent, though sensory sensitive, functional organization within the parietal cortex: a fMRI study of angle discrimination in sighted and congenitally blind individuals.

    PubMed

    Bonino, Daniela; Ricciardi, Emiliano; Bernardi, Giulio; Sani, Lorenzo; Gentili, Claudio; Vecchi, Tomaso; Pietrini, Pietro

    2015-02-01

    Although vision offers distinctive information to space representation, individuals who lack vision since birth often show perceptual and representational skills comparable to those found in sighted individuals. However, congenitally blind individuals may result in impaired spatial analysis, when engaging in 'visual' spatial features (e.g., perspective or angle representation) or complex spatial mental abilities. In the present study, we measured behavioral and brain responses using functional magnetic resonance imaging in sighted and congenitally blind individuals during spatial imagery based on a modified version of the mental clock task (e.g., angle discrimination) and a simple recognition control condition, as conveyed across distinct sensory modalities: visual (sighted individuals only), tactile and auditory. Blind individuals were significantly less accurate during the auditory task, but comparable-to-sighted during the tactile task. As expected, both groups showed common neural activations in intraparietal and superior parietal regions across visual and non-visual spatial perception and imagery conditions, indicating the more abstract, sensory independent functional organization of these cortical areas, a property that we named supramodality. At the same time, however, comparisons in brain responses and functional connectivity patterns across experimental conditions demonstrated also a functional lateralization, in a way that correlated with the distinct behavioral performance in blind and sighted individuals. Specifically, blind individuals relied more on right parietal regions, mainly in the tactile and less in the auditory spatial processing. In sighted, spatial representation across modalities relied more on left parietal regions. In conclusions, intraparietal and superior parietal regions subserve supramodal spatial representations in sighted and congenitally blind individuals. Differences in their recruitment across non-visual spatial processing in

  17. Quis custodiet ipsos custodies: who watches the watchmen?

    SciTech Connect

    Ghajar, Cyrus M.; Meier, Roland; Bissell, Mina J.

    2009-06-03

    Should this be said again? No cell is an island and in tissue-specificity and cancer, context is supreme. Decades ago, seminal recombination experiments illustrated the dominant role of mammary mesenchyme in directing epithelial development, and strongly suggested that the microenvironment plays a significant role also in the manifestation of carcinoma. More direct evidence for such functions came from a study demonstrating that an unadulterated microenvironment can suppress the malignant phenotype and re-direct tumor cells to give rise to normally functioning tissues and indeed healthy mice. One may wonder why such a stunning finding did not convince the scientific community to pay more attention to the role of context. The answers are complex, not the least of which is that concomitantly with this finding, the roles of oncogenes and mutations were being discovered. That excitement carried the day, specially because no one subsequently determined whether or not these mice generated from malignant cells contained tumorigenic mutations, and no new group reproduced the work. The following decade saw the discovery that even potent oncogenes could be ruled by context, and another couple of decades later it was shown that similar reprogramming of metastatic melanoma by an embryonic microenvironment was possible. There are many more examples which are not as clear cut, but are nevertheless compelling. The extensive literature of two-stage carcinogenesis, namely initiation and progression, indeed clearly indicates that 'initiation' and DNA damage alone are not sufficient to allow carcinogenesis. Implicit in these findings is: once a tumor or an oncogene, not always a tumor or an oncogene. A renewed focus on the tumor microenvironment as a therapeutic target has also led to the recognition that markers within the microenvironment could have predictive power. Two recently published reports identifying 'stromal signatures' in breast cancer patients prognostic for patient survival and predictive of response to chemotherapeutic treatment provide proof of this concept. In the current issue of The American Journal of Pathology, two independent studies identify a novel stromal marker, caveolin (Cav)-1, which predicts clinical outcome of breast cancer patients irrespective of its expression in tumor epithelium. Cav-1 is a scaffolding protein essential to the structure of caveolae, 'little caves' or invaginations in cellular plasma membranes. Cav-1 recruits and arranges lipids and proteins to these membrane sites to function in endocytosis and signal transduction. The observation that Cav-1 expression is attenuated in oncogenically transformed cells led to exploration of whether Cav-1 loss in mammary epithelium was causative. Although mechanistic data suggested that Cav-1 null mice exhibited aberrant epithelial growth, and that forcing Cav-1 expression in breast cancer cell lines inhibited growth and metastases in xenograft models, a clinical link proved elusive. However, MMTV-PyMT tumors transplanted into the fat pads of Cav-1 knockout mice displayed significantly enhanced growth (vs. wild-type mice), motivating investigation of whether stromal Cav-1 expression correlates with human breast cancer patient survival. This is precisely what Sloan et al. and Witkiewicz, Dasgupta, et al. demonstrate in this issue of AJP. Using tissue microarray data in conjunction with breast tumor sections and extensive patient survival data, Sloan et al. demonstrate that strong stromal Cav-1 expression is associated with smaller breast tumor size and grade, and is highly predictive of increased survival (Fig. 1). Patients with positive expression of stromal Cav-1 had a 91% ten year survival rate, vs. a 43% survival rate for patients lacking stromal Cav-1 expression. Importantly, there was no correlation between Cav-1 expression in the tumor epithelium and clinical outcome in either tissue arrays or tumor sections.

  18. Saccade target selection relies on feedback competitive signal integration.

    PubMed

    Kalisvaart, Joke P; Noest, André J; van den Berg, Albert V; Goossens, Jeroen

    2013-07-17

    It is often assumed that decision making involves neural competition, accumulation of evidence "scores" over time, and commitment to a particular alternative once its scores reach a critical decision threshold first. So far, however, neither the first-to-threshold rule nor the nature of competition (feedforward or feedback inhibition) has been revealed by experiments. Here, we presented two simultaneously flashed targets that reversed their intensity difference during each presentation and instructed human subjects to make a saccade toward the brightest target. All subjects preferentially chose the target that was brightest during the first stimulus phase. Unless this first phase lasted only 40 ms, this primacy effect persisted even if the second, reversed-intensity phase lasted longer. This effect did not result from premature commitment to the initially dominant target, because a strong target imbalance in the opposite direction later drove nearly all responses toward that location. Moreover, there was a nonmonotonic relation between target imbalance and primacy: increasing the target imbalance beyond 40 cd/m(2) caused an attenuation of primacy. These are the hallmarks of hysteresis, predicted by models in which target representations compete through strong feedback. Reaction times were independent of the choice probability. This dissociation suggests that target selection and movement initiation are distinct phenomena.

  19. Number Estimation Relies on a Set of Segmented Objects

    ERIC Educational Resources Information Center

    Franconeri, S. L.; Bemis, D. K.; Alvarez, G. A.

    2009-01-01

    How do we estimate the number of objects in a set? Two types of visual representations might underlie this ability--an unsegmented visual image or a segmented collection of discrete objects. We manipulated whether individual objects were isolated from each other or grouped into pairs by irrelevant lines. If number estimation operates over an…

  20. Tubercle bacilli rely on a type VII army for pathogenicity.

    PubMed

    Stoop, Esther J M; Bitter, Wilbert; van der Sar, Astrid M

    2012-10-01

    Mycobacteria, such as the major human pathogen Mycobacterium tuberculosis, have a highly unusual and characteristic diderm cell envelope that protects them against harmful conditions. Protein secretion across this hydrophobic barrier requires specialized secretion systems. Recently, a type VII secretion (T7S) pathway has been identified that fulfills this function. Pathogenic mycobacteria have up to five different T7S systems, some of which play a crucial role in virulence. The interactions between secreted substrates and host molecules are only starting to become clear and will help in furthering our understanding of the persistence of these enigmatic pathogens. In this review, we discuss current knowledge on the role of T7S systems in mycobacterial virulence.

  1. Reinforcement learning in multidimensional environments relies on attention mechanisms.

    PubMed

    Niv, Yael; Daniel, Reka; Geana, Andra; Gershman, Samuel J; Leong, Yuan Chang; Radulescu, Angela; Wilson, Robert C

    2015-05-27

    In recent years, ideas from the computational field of reinforcement learning have revolutionized the study of learning in the brain, famously providing new, precise theories of how dopamine affects learning in the basal ganglia. However, reinforcement learning algorithms are notorious for not scaling well to multidimensional environments, as is required for real-world learning. We hypothesized that the brain naturally reduces the dimensionality of real-world problems to only those dimensions that are relevant to predicting reward, and conducted an experiment to assess by what algorithms and with what neural mechanisms this "representation learning" process is realized in humans. Our results suggest that a bilateral attentional control network comprising the intraparietal sulcus, precuneus, and dorsolateral prefrontal cortex is involved in selecting what dimensions are relevant to the task at hand, effectively updating the task representation through trial and error. In this way, cortical attention mechanisms interact with learning in the basal ganglia to solve the "curse of dimensionality" in reinforcement learning.

  2. Relying on electronic journals: Reading patterns of astronomers

    NASA Astrophysics Data System (ADS)

    Tenopir, Carol; King, Donald W.; Boyce, Peter; Grayson, Matt; Paulson, Keri-Lynn

    2005-06-01

    Surveys of the members of the American Astronomical Society identify how astronomers use journals and what features and formats they prefer. While every work field is distinct, the patterns of use by astronomers may provide a glimpse of what to expect of journal patterns and use by other scientists. Astronomers, like other scientists, continue to invest a large amount of their time in reading articles and place a high level of importance on journal articles. They use a wide variety of formats and means to get access to materials that are essential to their work in teaching, service, and research. They select access means that are convenient - whether those means be print, electronic, or both. The availability of a mature electronic journals system from their primary professional society has surely influenced their early adoption of e-journals.

  3. Colleges Rely on Consortia, Contractors, and Ingenuity to Cut Costs

    ERIC Educational Resources Information Center

    Gose, Ben

    2006-01-01

    The US colleges are struggling with soaring tuition costs as state support is unable to keep up with enrollment growth, and college officials are becoming more creative in finding ways to reduce expenses. Higher education institutions are increasingly outsourcing non-academic activities, collaborating with other institutions to share goods and…

  4. An efficient circle detector not relying on edge detection

    NASA Astrophysics Data System (ADS)

    Cai, Jia; Huang, Panfeng; Chen, Lu; Zhang, Bin

    2016-06-01

    Accurate and efficient detection of circular modules fixed on non-cooperative target is a key technology for Tethered Space Robot. This paper presents an efficient circle detector based on region-growing of gradient and histogram distribution of Euclidean distance. Region-growing of gradient is applied to generate arc support regions from single point. And the corresponding square fitting areas are defined to accelerate the detection and decrease storage. A histogram is then used to count frequency of the distances that participates in the accumulator and the parameters of each circle are acquired. Finally, a verification strategy of circular integrity is designed to test the detection results. We have tested our algorithm on 35 images dealing with kinds of circles and ellipses. Experimental results demonstrate that our method is able to detect circular objects under occlusion, image noises and moderate shape deformations with a good precision.

  5. Mosquitoes rely on their gut microbiota for development

    PubMed Central

    Coon, Kerri L.; Vogel, Kevin J.; Brown, Mark R.; Strand, Michael R.

    2014-01-01

    Field studies indicate adult mosquitoes (Culicidae) host low diversity communities of bacteria that vary greatly among individuals and species. In contrast, it remains unclear how adult mosquitoes acquire their microbiome, what influences community structure, and whether the microbiome is important for survival. Here we used pyrosequencing of 16S rRNA to characterize the bacterial communities of three mosquito species reared under identical conditions. Two of these species, Aedes aegypti and Anopheles gambiae, are anautogenous and must blood feed to produce eggs, while one, Georgecraigius atropalpus, is autogenous and produces eggs without blood feeding. Each mosquito species contained a low diversity community comprised primarily of aerobic bacteria acquired primarily from the aquatic habitat in which larvae developed. Our results suggested the communities in Ae. aegypti and An. gambiae larvae share more similarities with one another than with Ge. atropalpus. Studies with Ae. aegypti also strongly suggested that adults transstadially acquired several members of the larval bacterial community, but only four genera of bacteria present in blood fed females were detected on eggs. Functional assays showed that axenic larvae of each species failed to develop beyond the first instar. Experiments with Ae. aegypti indicated several members of the microbial community and Escherichia coli successfully colonized axenic larvae and rescued development. Overall, our results provide new insights about the acquisition and structure of bacterial communities in mosquitoes. They also indicate three mosquito species spanning the breadth of the Culicidae depend on their gut microbiome for development. PMID:24766707

  6. Questionable Practices? Relying on Individual Teacher Resilience in Remote Schools

    ERIC Educational Resources Information Center

    Sullivan, Anna; Johnson, Bruce

    2012-01-01

    Early career teachers eager to find employment are often encouraged by employers to accept positions in remote locations which are traditionally difficult to staff. This paper reports research that examined a case study of a graduate teacher employed in a remote school. Drawing on resilience theory, we challenge the profession to consider whether…

  7. Visual predictions in the orbitofrontal cortex rely on associative content.

    PubMed

    Chaumon, Maximilien; Kveraga, Kestutis; Barrett, Lisa Feldman; Bar, Moshe

    2014-11-01

    Predicting upcoming events from incomplete information is an essential brain function. The orbitofrontal cortex (OFC) plays a critical role in this process by facilitating recognition of sensory inputs via predictive feedback to sensory cortices. In the visual domain, the OFC is engaged by low spatial frequency (LSF) and magnocellular-biased inputs, but beyond this, we know little about the information content required to activate it. Is the OFC automatically engaged to analyze any LSF information for meaning? Or is it engaged only when LSF information matches preexisting memory associations? We tested these hypotheses and show that only LSF information that could be linked to memory associations engages the OFC. Specifically, LSF stimuli activated the OFC in 2 distinct medial and lateral regions only if they resembled known visual objects. More identifiable objects increased activity in the medial OFC, known for its function in affective responses. Furthermore, these objects also increased the connectivity of the lateral OFC with the ventral visual cortex, a crucial region for object identification. At the interface between sensory, memory, and affective processing, the OFC thus appears to be attuned to the associative content of visual information and to play a central role in visuo-affective prediction. PMID:23771980

  8. Rodents rely upon Merkel cells for texture discrimination tasks

    PubMed Central

    Maricich, Stephen M.; Morrison, Kristin M.; Mathes, Erin L.; Brewer, Brittany M.

    2012-01-01

    The cutaneous somatosensory system contains multiple types of mechanoreceptors that detect different mechanical stimuli (Johnson, 2001). These stimuli, either alone or in combination, are ultimately interpreted by the brain as different aspects of the sense of touch. Psychophysical and electrophysiological experiments in humans and other mammals implicate one of these mechanoreceptors, the Merkel cell/neurite complex, in two-point discrimination and the detection of curvature, shape and texture (Johnson and Lamb, 1981; Johnson et al., 2000; Johnson, 2001). However, whether Merkel cell/neurite complex function is required for the detection of these stimuli is unknown. We genetically engineered mice that lack Merkel cells (Maricich et al., 2009; Morrison et al., 2009) to directly test the hypothesis that Merkel cell/neurite complexes are necessary to perform these types of sensory discrimination tasks. We found that mice devoid of Merkel cells could not detect textured surfaces with their feet while other measures of motor and sensory function were unaffected. Interestingly, these mice retained the ability to discriminate both texture and shape using their whiskers, suggesting that other somatosensory afferents can functionally substitute for Merkel cell/neurite complexes in this sensory organ. These findings suggest that Merkel cell/neurite complexes are essential for texture discrimination tasks involving glabrous skin but not whiskers. PMID:22399751

  9. [We rely on the common sense of young people].

    PubMed

    Kudriavtseva, M V

    2000-01-01

    The principles of the primary prophylaxis, analogous to the program "Harm Reduction", are presented. The basis for placing this work on broad footing was the rapid assessment of the situation with the use of narcotic drugs in the city (the number of users exceeded 10,000 per 238,000 inhabitants) with a tendency towards a sharp decrease of the age of the users (9-13 years). The experience of work on the training of medical personnel, directly contacting with blood and thus considered to be a risk group, taking into account risky professional behavior (potentially dangerous), was accumulated. The training activities among students of medical schools proved to be effective. They became the best volunteers and leaders among young people. Adolescents aged 14-18 years were enlisted as volunteers: they worked in different places usually attended by young people and invited drug addicts to the anonymous examination room. The role of local mass media in educating the public on of the problems of the prevention of HIV infection is discussed. As a result, the activation of the youth movement in support of the program "Anti-AIDS" and an increase in the number of people in target groups coming to the anonymous examination room are noted.

  10. Estimation of the impact of warfarin's time-in-therapeutic range on stroke and major bleeding rates and its influence on the medical cost avoidance associated with novel oral anticoagulant use-learnings from ARISTOTLE, ROCKET-AF, and RE-LY trials.

    PubMed

    Amin, Alpesh; Deitelzweig, Steve; Jing, Yonghua; Makenbaeva, Dinara; Wiederkehr, Daniel; Lin, Jay; Graham, John

    2014-01-01

    Warfarin's time-in-therapeutic range (TTR) is highly variable among patients with nonvalvular atrial fibrillation (NVAF). The objective of this study was to estimate the impact of variations in wafarin's TTR on rates of stroke/systemic embolism (SSE) and major bleedings among NVAF patients in the ARISTOTLE, ROCKET-AF, and RE-LY trials. Additionally, differences in medical costs for clinical endpoints when novel oral anticoagulants (NOACs) were used instead of warfarin at different TTR values were estimated. Quartile ranges of TTR values and corresponding event rates (%/patient - year = %/py) of SSE and major bleedings among NVAF patients treated with warfarin were estimated from published literature and FDA documents. The associations of SSE and major bleeding rates with TTR values were evaluated by regression analysis and then the calculated regression coefficients were used in analysis of medical cost differences associated with use of each NOAC versus warfarin (2010 costs; US payer perspective) at different TTRs. Each 10 % increase in warfarin's TTR correlated with a -0.32%/py decrease in SSE rate (R(2) = 0.61; p < 0.001). Although, the rate of major bleedings decreased as TTR increased, it was not significant (-0.035%/py, p = 0.63). As warfarin's TTR increased from 30 to 90% the estimated medical cost decreased from -$902 to -$83 for apixaban, from -$506 to +$314 for rivaroxaban, and from -$596 to +$223 for dabigatran. Among NVAF patients there is a significant negative correlation between warfarin's TTR and SSE rate, but not major bleedings. The variations in warfarin's TTR impacted the economic comparison of use of individual NOACs versus warfarin.

  11. Who Cares for Children? Notes, Comments... No. 188 = Les enfants, qui s'en soucie?

    ERIC Educational Resources Information Center

    Bronfenbrenner, Urie

    The finding of positive effects of developmentally sensitive interaction on children's physical health is discussed and expanded in terms of five propositions. The first is that development requires participation in progressively more complex reciprocal activities on a regular basis over an extended period of time, with at least one person…

  12. 77 FR 27245 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-09

    ... articles, internet postings, and other media announcements to inform people of opportunities for input... Register (73 FR 76677) on December 17, 2008. For more about the initial process and the history of this..., wildlife observation and photography, and environmental education and interpretation. We will review...

  13. Brazilian Federal Police drug chemical profiling - the PeQui project.

    PubMed

    Zacca, Jorge J; Botelho, Elvio Dias; Vieira, Maurício L; Almeida, Fernanda L A; Ferreira, Luciana S; Maldaner, Adriano O

    2014-07-01

    Over the past six years the Brazilian Federal Police has undertaken major efforts in order to implement and to develop its own drug chemical profiling program. This paper aims to provide a broad perspective regarding the managerial strategies and some examples of subsequent technical issues involved in the implementation of such a project. Close collaboration with local drug enforcement and investigation teams, establishment of proper worldwide partnerships with well recognized institutions in the field of drug analysis and the attainment of suitable funding and human resources are shown to be key success factors. Some preliminary results concerning the chemical profile of cocaine seizures in Brazil during this process are presented. PMID:25002048

  14. Qui sera le nouvel Einstein ? Vers une nouvelle theorie de la gravitation

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1999-10-01

    Un debat de plus d'un siecle a resurgi ces toutes dernieres annees avec une vigueur nouvelle. L'enjeu ? Mettre fin, ni plus ni moins, a l'une des contradictions les plus inouies de la physique fondamentale, en reconciliant mecanique quantique et relativite generale. En effet, a l'heure ou la gravitation semble enfin sur le point de fusionner avec les trois autres forces de la nature. il est certain que la relativite d'Einstein doit etre bientot remplacer par une autre theorie... Reste quye tous les physiciens sont loin de s'accorder sur la marche a suivree. Gravitation quantique, relativite d'echelle, supersymetrie, les candidates ne manquent pas.

  15. Le verbe qui vole; mot de l'enterprete (The Flying Verb; The Interpreter's Word)

    ERIC Educational Resources Information Center

    Romer, Therese

    1975-01-01

    After a brief discussion on the nature of the interpreter's work, a survey is made of the beginnings of interpreting as a profession in 1953 and its growth since then in North America and Europe. Attention is called to the problem of incompetence brought about by the growing number of interpreters; and to the need for professional interpreter…

  16. Desiccation Tolerance in the Tardigrade Richtersius coronifer Relies on Muscle Mediated Structural Reorganization

    PubMed Central

    Halberg, Kenneth Agerlin; Jørgensen, Aslak; Møbjerg, Nadja

    2013-01-01

    Life unfolds within a framework of constraining abiotic factors, yet some organisms are adapted to handle large fluctuations in physical and chemical parameters. Tardigrades are microscopic ecdysozoans well known for their ability to endure hostile conditions, such as complete desiccation – a phenomenon called anhydrobiosis. During dehydration, anhydrobiotic animals undergo a series of anatomical changes. Whether this reorganization is an essential regulated event mediated by active controlled processes, or merely a passive result of the dehydration process, has not been clearly determined. Here, we investigate parameters pivotal to the formation of the so-called "tun", a state that in tardigrades and rotifers marks the entrance into anhydrobiosis. Estimation of body volume in the eutardigrade Richtersius coronifer reveals an 87 % reduction in volume from the hydrated active state to the dehydrated tun state, underlining the structural stress associated with entering anhydrobiosis. Survival experiments with pharmacological inhibitors of mitochondrial energy production and muscle contractions show that i) mitochondrial energy production is a prerequisite for surviving desiccation, ii) uncoupling the mitochondria abolishes tun formation, and iii) inhibiting the musculature impairs the ability to form viable tuns. We moreover provide a comparative analysis of the structural changes involved in tun formation, using a combination of cytochemistry, confocal laser scanning microscopy and 3D reconstructions as well as scanning electron microscopy. Our data reveal that the musculature mediates a structural reorganization vital for anhydrobiotic survival, and furthermore that maintaining structural integrity is essential for resumption of life following rehydration. PMID:24391987

  17. Relying on Your Own Best Judgment: Imputing Values to Missing Information in Decision Making.

    ERIC Educational Resources Information Center

    Johnson, Richard D.; And Others

    Processes involved in making estimates of the value of missing information that could help in a decision making process were studied. Hypothetical purchases of ground beef were selected for the study as such purchases have the desirable property of quantifying both the price and quality. A total of 150 students at the University of Iowa rated the…

  18. Eiger-induced cell death relies on Rac1-dependent endocytosis

    PubMed Central

    Ruan, W; Srinivasan, A; Lin, S; Kara, k-I; Barker, P A

    2016-01-01

    Signaling via tumor necrosis factor receptor (TNFR) superfamily members regulates cellular life and death decisions. A subset of mammalian TNFR proteins, most notably the p75 neurotrophin receptor (p75NTR), induces cell death through a pathway that requires activation of c-Jun N-terminal kinases (JNKs). However the receptor-proximal signaling events that mediate this remain unclear. Drosophila express a single tumor necrosis factor (TNF) ligand termed Eiger (Egr) that activates JNK-dependent cell death. We have exploited this model to identify phylogenetically conserved signaling events that allow Egr to induce JNK activation and cell death in vivo. Here we report that Rac1, a small GTPase, is specifically required in Egr-mediated cell death. rac1 loss of function blocks Egr-induced cell death, whereas Rac1 overexpression enhances Egr-induced killing. We identify Vav as a GEF for Rac1 in this pathway and demonstrate that dLRRK functions as a negative regulator of Rac1 that normally acts to constrain Egr-induced death. Thus dLRRK loss of function increases Egr-induced cell death in the fly. We further show that Rac1-dependent entry of Egr into early endosomes is a crucial prerequisite for JNK activation and for cell death and show that this entry requires the activity of Rab21 and Rab7. These findings reveal novel regulatory mechanisms that allow Rac1 to contribute to Egr-induced JNK activation and cell death. PMID:27054336

  19. Spider orb webs rely on radial threads to absorb prey kinetic energy.

    PubMed

    Sensenig, Andrew T; Lorentz, Kimberly A; Kelly, Sean P; Blackledge, Todd A

    2012-08-01

    The kinetic energy of flying insect prey is a formidable challenge for orb-weaving spiders. These spiders construct two-dimensional, round webs from a combination of stiff, strong radial silk and highly elastic, glue-coated capture spirals. Orb webs must first stop the flight of insect prey and then retain those insects long enough to be subdued by the spiders. Consequently, spider silks rank among the toughest known biomaterials. The large number of silk threads composing a web suggests that aerodynamic dissipation may also play an important role in stopping prey. Here, we quantify energy dissipation in orb webs spun by diverse species of spiders using data derived from high-speed videos of web deformation under prey impact. By integrating video data with material testing of silks, we compare the relative contributions of radial silk, the capture spiral and aerodynamic dissipation. Radial silk dominated energy absorption in all webs, with the potential to account for approximately 100 per cent of the work of stopping prey in larger webs. The most generous estimates for the roles of capture spirals and aerodynamic dissipation show that they rarely contribute more than 30 per cent and 10 per cent of the total work of stopping prey, respectively, and then only for smaller orb webs. The reliance of spider orb webs upon internal energy absorption by radial threads for prey capture suggests that the material properties of the capture spirals are largely unconstrained by the selective pressures of stopping prey and can instead evolve freely in response to alternative functional constraints such as adhering to prey.

  20. An Unexpected Route to an Essential Cofactor: Escherichia coli Relies on Threonine for Thiamine Biosynthesis

    PubMed Central

    Bazurto, Jannell V.; Farley, Kristen R.

    2016-01-01

    ABSTRACT Metabolism consists of biochemical reactions that are combined to generate a robust metabolic network that can respond to perturbations and also adapt to changing environmental conditions. Escherichia coli and Salmonella enterica are closely related enterobacteria that share metabolic components, pathway structures, and regulatory strategies. The synthesis of thiamine in S. enterica has been used to define a node of the metabolic network by analyzing alternative inputs to thiamine synthesis from diverse metabolic pathways. To assess the conservation of metabolic networks in organisms with highly conserved components, metabolic contributions to thiamine synthesis in E. coli were investigated. Unexpectedly, we found that, unlike S. enterica, E. coli does not use the phosphoribosylpyrophosphate (PRPP) amidotransferase (PurF) as the primary enzyme for synthesis of phosphoribosylamine (PRA). In fact, our data showed that up to 50% of the PRA used by E. coli to make thiamine requires the activities of threonine dehydratase (IlvA) and anthranilate synthase component II (TrpD). Significantly, the IlvA- and TrpD-dependent pathway to PRA functions in S. enterica only in the absence of a functional reactive intermediate deaminase (RidA) enzyme, bringing into focus how these closely related bacteria have distinct metabolic networks. PMID:26733068

  1. "Depend on, Rely on, Count on": Economic Subjectivities Aboard "The Polar Express"

    ERIC Educational Resources Information Center

    Saltmarsh, Sue

    2009-01-01

    Christmas literature and film produced for children is an important, albeit under-researched, site for the production of cultural values and norms. This paper analyses Chris Van Allsburg's 1985 picture book "The Polar Express", the 2004 Warner Brothers feature film of the same title, the film's official website, and resources for teachers…

  2. Deferring Higher Education Fees without Relying on Contributions from Non-Students

    ERIC Educational Resources Information Center

    Del Rey, Elena

    2012-01-01

    The benefits of deferring the payment of higher-education costs are increasingly acknowledged as a way to overcome student-borrowing constraints. Since higher education is a risky investment and students are generally risk averse, the repayment arrangements proposed in the literature frequently include some insurance. In a competitive environment,…

  3. Gustatory Habituation in "Drosophila" Relies on "Rutabaga" (Adenylate Cyclase)-Dependent Plasticity of GABAergic Inhibitory Neurons

    ERIC Educational Resources Information Center

    Paranjpe, Pushkar; Rodrigues, Veronica; VijayRaghavan, K.; Ramaswami, Mani

    2012-01-01

    In some situations, animals seem to ignore stimuli which in other contexts elicit a robust response. This attenuation in behavior, which enables animals to ignore a familiar, unreinforced stimulus, is called habituation. Despite the ubiquity of this phenomenon, it is generally poorly understood in terms of the underlying neural circuitry. Hungry…

  4. Evolutionary differences in food preference rely on Gr64e, a receptor for glycerol.

    PubMed

    Wisotsky, Zev; Medina, Adriana; Freeman, Erica; Dahanukar, Anupama

    2011-12-01

    Very little is known about how stimuli that are typically not rich in sugars, such as beer, trigger attractive gustatory responses in Drosophila. We identified a member of the gustatory receptor family, Gr64e, as a receptor that is required for feeding preference for beer and other sources that have fermenting yeast. We found that Gr64e is required for neuronal and behavioral responses to glycerol, an abundant component of growing yeast and fermentation products. Ectopic expression of Gr64e in an olfactory neuron conferred responsiveness to glycerol. We also found that Drosophila species that are predicted to carry pseudogenes of Gr64e had reduced glycerol sensitivity. Our results provide insight into the molecular mechanisms of feeding acceptance of yeast products and raise the possibility that Gr64e contributes to specific evolutionary variations in appetitive selectivity across Drosophila species. PMID:22057190

  5. Do Young and Older Adults Rely on Different Processes in Source Memory Tasks? A Neuropsychological Study

    ERIC Educational Resources Information Center

    Glisky, Elizabeth L.; Kong, Lauren L.

    2008-01-01

    Source memory has consistently been associated with prefrontal function in both normal and clinical populations. Nevertheless, the exact contribution of this brain region to source memory remains uncertain, and evidence suggests that processes used by young and older adults may differ. The authors explored the extent to which scores on composite…

  6. Extinction of cue-evoked drug-seeking relies on degrading hierarchical instrumental expectancies.

    PubMed

    Hogarth, Lee; Retzler, Chris; Munafò, Marcus R; Tran, Dominic M D; Troisi, Joseph R; Rose, Abigail K; Jones, Andrew; Field, Matt

    2014-08-01

    There has long been need for a behavioural intervention that attenuates cue-evoked drug-seeking, but the optimal method remains obscure. To address this, we report three approaches to extinguish cue-evoked drug-seeking measured in a Pavlovian to instrumental transfer design, in non-treatment seeking adult smokers and alcohol drinkers. The results showed that the ability of a drug stimulus to transfer control over a separately trained drug-seeking response was not affected by the stimulus undergoing Pavlovian extinction training in experiment 1, but was abolished by the stimulus undergoing discriminative extinction training in experiment 2, and was abolished by explicit verbal instructions stating that the stimulus did not signal a more effective response-drug contingency in experiment 3. These data suggest that cue-evoked drug-seeking is mediated by a propositional hierarchical instrumental expectancy that the drug-seeking response is more likely to be rewarded in that stimulus. Methods which degraded this hierarchical expectancy were effective in the laboratory, and so may have therapeutic potential. PMID:25011113

  7. Anticancer immunotherapy by CTLA-4 blockade relies on the gut microbiota

    PubMed Central

    Vétizou, Marie; Pitt, Jonathan M.; Daillère, Romain; Lepage, Patricia; Waldschmitt, Nadine; Flament, Caroline; Rusakiewicz, Sylvie; Routy, Bertrand; Roberti, Maria P.; Duong, Connie P. M.; Poirier-Colame, Vichnou; Roux, Antoine; Becharef, Sonia; Formenti, Silvia; Golden, Encouse; Cording, Sascha; Eberl, Gerard; Schlitzer, Andreas; Ginhoux, Florent; Mani, Sridhar; Yamazaki, Takahiro; Jacquelot, Nicolas; Enot, David P.; Bérard, Marion; Nigou, Jérôme; Opolon, Paule; Eggermont, Alexander; Woerther, Paul-Louis; Chachaty, Elisabeth; Chaput, Nathalie; Robert, Caroline; Mateus, Christina; Kroemer, Guido; Raoult, Didier; Boneca, Ivo Gomperts; Carbonnel, Franck; Chamaillard, Mathias; Zitvogel, Laurence

    2016-01-01

    Antibodies targeting CTLA-4 have been successfully used as cancer immunotherapy. We find that the antitumor effects of CTLA-4 blockade depend on distinct Bacteroides species. In mice and patients, T cell responses specific for B. thetaiotaomicron or B. fragilis were associated with the efficacy of CTLA-4 blockade. Tumors in antibiotic-treated or germ-free mice did not respond to CTLA blockade. This defect was overcome by gavage with B. fragilis, by immunization with B. fragilis polysaccharides, or by adoptive transfer of B. fragilis–specific T cells. Fecal microbial transplantation from humans to mice confirmed that treatment of melanoma patients with antibodies against CTLA-4 favored the outgrowth of B. fragilis with anticancer properties. This study reveals a key role for Bacteroidales in the immunostimulatory effects of CTLA-4 blockade. PMID:26541610

  8. The "contemporary synthesis": when politically inclusive genomic science relies on biological notions of race.

    PubMed

    Fullwiley, Duana

    2014-12-01

    This essay outlines the emergence of a contemporary synthesis regarding racial thinking in genetic science and in society more broadly. A departure from what Julian Huxley in 1942 termed the "modern synthesis," the contemporary version does not purport to leave race thinking behind in favor of evolution, population genetics, and population-based accounts of natural selection and human diversity. Specifically, the contemporary synthesis blends old concepts (such as that of pure human "types," located within continental land masses) with new attitudes (democratic inclusion, multicultural diversity, and anti-racism). Through various examples, the essay shows how this new synthesis combines ideas about human biological difference that draw on measures of physical characteristics and human genetic material that are both race and population based, yet conflated. This specific amalgam allows old notions of racial types to thrive through conceptual framings that comprise ideas that were once imagined to have the potential to liberate society from racial thinking--and that today remain attached to ideas of progress. As an emergent dynamic, the contemporary synthesis holds the possibility of reinvigorating racism, while simultaneously possessing the potential to promote antiracist science education, disease awareness, and social justice efforts.

  9. Resting lymphocyte transduction with measles virus glycoprotein pseudotyped lentiviral vectors relies on CD46 and SLAM

    SciTech Connect

    Zhou Qi; Schneider, Irene C.; Gallet, Manuela; Kneissl, Sabrina; Buchholz, Christian J.

    2011-05-10

    The measles virus (MV) glycoproteins hemagglutinin (H) and fusion (F) were recently shown to mediate transduction of resting lymphocytes by lentiviral vectors. MV vaccine strains use CD46 or signaling lymphocyte activation molecule (SLAM) as receptor for cell entry. A panel of H protein mutants derived from vaccine strain or wild-type MVs that lost or gained CD46 or SLAM receptor usage were investigated for their ability to mediate gene transfer into unstimulated T lymphocytes. The results demonstrate that CD46 is sufficient for efficient vector particle association with unstimulated lymphocytes. For stable gene transfer into these cells, however, both MV receptors were found to be essential.

  10. Single-Molecule Motions of MHC Class II Rely on Bound Peptides

    PubMed Central

    Kozono, Haruo; Matsushita, Yufuku; Ogawa, Naoki; Kozono, Yuko; Miyabe, Toshihiro; Sekiguchi, Hiroshi; Ichiyanagi, Kouhei; Okimoto, Noriaki; Taiji, Makoto; Kanagawa, Osami; Sasaki, Yuji C.

    2015-01-01

    The major histocompatibility complex (MHC) class II protein can bind peptides of different lengths in the region outside the peptide-binding groove. Peptide-flanking residues (PFRs) contribute to the binding affinity of the peptide for MHC and change the immunogenicity of the peptide/MHC complex with regard to T cell receptor (TCR). The mechanisms underlying these phenomena are currently unknown. The molecular flexibility of the peptide/MHC complex may be an important determinant of the structures recognized by certain T cells. We used single-molecule x-ray analysis (diffracted x-ray tracking (DXT)) and fluorescence anisotropy to investigate these mechanisms. DXT enabled us to monitor the real-time Brownian motion of the peptide/MHC complex and revealed that peptides without PFRs undergo larger rotational motions than peptides with PFRs. Fluorescence anisotropy further revealed that peptides without PFRs exhibit slightly larger motions on the nanosecond timescale. These results demonstrate that peptides without PFRs undergo dynamic motions in the groove of MHC and consequently are able to assume diverse structures that can be recognized by T cells. PMID:25606683

  11. Arsenate tolerance in Silene paradoxa does not rely on phytochelatin-dependent sequestration.

    PubMed

    Arnetoli, Miluscia; Vooijs, Riet; ten Bookum, Wilma; Galardi, Francesca; Gonnelli, Cristina; Gabbrielli, Roberto; Schat, Henk; Verkleij, Jos A C

    2008-04-01

    Arsenate tolerance, As accumulation and As-induced phytochelatin accumulation were compared in populations of Silene paradoxa, one from a mine site enriched in As, Cu and Zn, the other from an uncontaminated site. The mine population was significantly more arsenate-tolerant. Arsenate uptake and root-to-shoot transport were slightly but significantly higher in the non-mine plants. The difference in uptake was quantitatively insufficient to explain the difference in tolerance between the populations. As accumulation in the roots was similar in both populations, but the mine plants accumulated much less phytochelatins than the non-mine plants. The mean phytochelatin chain length, however, was higher in the mine population, possibly due to a constitutively lower cellular glutathione level. It is argued that the mine plants must possess an arsenic detoxification mechanism other than arsenate reduction and subsequent phytochelatin-based sequestration. This alternative mechanism might explain at least some part of the superior tolerance in the mine plants.

  12. Portable paper-based device for quantitative colorimetric assays relying on light reflectance principle.

    PubMed

    Li, Bowei; Fu, Longwen; Zhang, Wei; Feng, Weiwei; Chen, Lingxin

    2014-04-01

    This paper presents a novel paper-based analytical device based on the colorimetric paper assays through its light reflectance. The device is portable, low cost (<20 dollars), and lightweight (only 176 g) that is available to assess the cost-effectiveness and appropriateness of the original health care or on-site detection information. Based on the light reflectance principle, the signal can be obtained directly, stably and user-friendly in our device. We demonstrated the utility and broad applicability of this technique with measurements of different biological and pollution target samples (BSA, glucose, Fe, and nitrite). Moreover, the real samples of Fe (II) and nitrite in the local tap water were successfully analyzed, and compared with the standard UV absorption method, the quantitative results showed good performance, reproducibility, and reliability. This device could provide quantitative information very conveniently and show great potential to broad fields of resource-limited analysis, medical diagnostics, and on-site environmental detection.

  13. Viroids: from genotype to phenotype just relying on RNA sequence and structural motifs.

    PubMed

    Flores, Ricardo; Serra, Pedro; Minoia, Sofía; Di Serio, Francesco; Navarro, Beatriz

    2012-01-01

    As a consequence of two unique physical properties, small size and circularity, viroid RNAs do not code for proteins and thus depend on RNA sequence/structural motifs for interacting with host proteins that mediate their invasion, replication, spread, and circumvention of defensive barriers. Viroid genomes fold up on themselves adopting collapsed secondary structures wherein stretches of nucleotides stabilized by Watson-Crick pairs are flanked by apparently unstructured loops. However, compelling data show that they are instead stabilized by alternative non-canonical pairs and that specific loops in the rod-like secondary structure, characteristic of Potato spindle tuber viroid and most other members of the family Pospiviroidae, are critical for replication and systemic trafficking. In contrast, rather than folding into a rod-like secondary structure, most members of the family Avsunviroidae adopt multibranched conformations occasionally stabilized by kissing-loop interactions critical for viroid viability in vivo. Besides these most stable secondary structures, viroid RNAs alternatively adopt during replication transient metastable conformations containing elements of local higher-order structure, prominent among which are the hammerhead ribozymes catalyzing a key replicative step in the family Avsunviroidae, and certain conserved hairpins that also mediate replication steps in the family Pospiviroidae. Therefore, different RNA structures - either global or local - determine different functions, thus highlighting the need for in-depth structural studies on viroid RNAs.

  14. How do groundwater-dependent lakes react if the aquifer they rely on is being pumped?

    NASA Astrophysics Data System (ADS)

    Vainu, Marko; Terasmaa, Jaanus

    2015-04-01

    Groundwater is a valuable source of drinking water, but at the same time it is the primary contributor to the existence of many surface water bodies. If the latter truth is overlooked in water resources management, and ground- and surface water are not considered as a single resource, then the sustainability of groundwater-dependent ecosystems will become under threat. The necessity for implementing an integrated management of ground- and surface water has also been stressed in the EU Water Framework Directive. This study aims to evaluate the effect of increased groundwater abstraction to groundwater and lake levels; and to evaluate the effect of increased groundwater abstraction to the seepage patterns in one example lake. The Kurtna Lake District in northeastern Estonia contains almost 40 small lakes which are situated in and around the Kurtna Kame Field and constitute an EU Special Area of Conservation. The sands that form the kame field contain a Quaternary groundwater aquifer. Water has been pumped from the aquifer for household use with varying rates since the 1970s, but starting from the summer of 2012 the average pumping rate was increased by 51% compared to the year before. During the current study the water levels of five lakes were monitored regularly from May 2012 to June 2013 - before and after the increase in the pumping rate. The water levels dropped 0.3 to 0.7 m during the year in three closed-basin lakes closest to the abstraction wells, but did not change neither in a flow-through lake nor in a closed-basin lake situated 1.6 km from the wells. Groundwater level in the aquifer (monitored by the Estonian Geological Survey) dropped up to 0.8 m near the abstraction wells in the course of the year, but did not change further from the wells. The estimates of average annual groundwater recharge were derived for the twelve months before both June 2012 and June 2013. Although the recharge rate was lower in the first year, the water-level drop was nevertheless caused by the higher pumping rate, because the effects of lower recharge would have affected the whole aquifer, not just a part of it. At the beginning of June 2012 and June 2013 also lake-bed seepage was directly measured in the bottom of one of the lakes (Lake Martiska). Seepage measurements in the first year showed that outseepage from L. Martiska occurred in the northern part of the lake, which is situated closest to the abstraction wells. For the second year the area of outseepage had widened towards the western shore of the lake. Therefore the increased abstraction rate had initiated the shrinking of these lakes near the abstraction wells that were hydraulically connected to the aquifer. The results of the rare opportunity to analyse lake-groundwater interactions both before and after increased human intervention provide a cautionary example of what may happen to and in groundwater-dependent lakes if the surface water-groundwater interactions are not fully clarified before the intervention.

  15. Whom Do Centenarians Rely on for Support? Findings From the Second Heidelberg Centenarian Study.

    PubMed

    Boerner, Kathrin; Jopp, Daniela S; Park, Min-Kyung S; Rott, Christoph

    2016-01-01

    This paper provides a detailed picture of the sources and types of informal support available to centenarians, depending on their housing and care arrangements. Participants were 112 centenarians and 96 primary contacts of centenarians enrolled in the population-based Second Heidelberg Centenarian Study. Findings indicate that children of centenarians were their primary source of support in daily life. Those without living children had overall less help. Most frequently reported was help with administrative tasks, regardless of centenarians' residence or living arrangement. All other types of help (e.g., with activities of daily living and housework) were reported by about one-third and were mostly provided by children; centenarians without children were more likely to have friends/neighbors involved in some of these tasks. The one category reported by a third of the centenarians regardless of residence, living arrangements, or presence of a child was help with socializing/companionship. Findings constitute an important step toward identifying and meeting the support needs of centenarians and their families. Policy implications are discussed.

  16. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon

    SciTech Connect

    Weinberg, C.R.

    1995-11-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of {alpha}-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining {alpha}-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting {open_quotes}measurement confounding{close_quotes} can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. 18 refs., 4 figs.

  17. Relies of reconciliation: the Confederate Museum and Civil War memory in the New South.

    PubMed

    Hillyer, Reiko

    2011-11-01

    This article examines the Confederate Memorial Literary Society (CMLS), an organization of elite white women in Richmond, Virginia who founded the Confederate Museum in the 1890s. Faced with the plunder of Civil War relics and cultural homogenization on northern terms, the CMLS founded the Confederate Museum to document and defend the Confederate cause and to uphold the antebellum mores that the New South's business ethos threatened to erode. In the end, however, the museum's version of the Lost Cause served the New South. By focusing on military sacrifice, the Confederate Museum aided the process of sectional reconciliation. By depicting slavery as benevolent, the museum's exhibits reinforced the notion that Jim Crow was a just and effective means of managing postwar southern society. Lastly, by glorifying the common soldier and portraying the South as "solid," the museum promoted obedience to the mandates of industrial capitalism. Thus, the Confederate Museum both critiqued and eased the economic transformations of the New South.

  18. Persistent cell migration and adhesion rely on retrograde transport of β(1) integrin.

    PubMed

    Shafaq-Zadah, Massiullah; Gomes-Santos, Carina S; Bardin, Sabine; Maiuri, Paolo; Maurin, Mathieu; Iranzo, Julian; Gautreau, Alexis; Lamaze, Christophe; Caswell, Patrick; Goud, Bruno; Johannes, Ludger

    2016-01-01

    Integrins have key functions in cell adhesion and migration. How integrins are dynamically relocalized to the leading edge in highly polarized migratory cells has remained unexplored. Here, we demonstrate that β1 integrin (known as PAT-3 in Caenorhabditis elegans), but not β3, is transported from the plasma membrane to the trans-Golgi network, to be resecreted in a polarized manner. This retrograde trafficking is restricted to the non-ligand-bound conformation of β1 integrin. Retrograde trafficking inhibition abrogates several β1-integrin-specific functions such as cell adhesion in early embryonic development of mice, and persistent cell migration in the developing posterior gonad arm of C. elegans. Our results establish a paradigm according to which retrograde trafficking, and not endosomal recycling, is the key driver for β1 integrin function in highly polarized cells. These data more generally suggest that the retrograde route is used to relocalize plasma membrane machinery from previous sites of function to the leading edge of migratory cells.

  19. Galileo IOV Electrical Power Subsystem Relies On Li-Ion Batter Charge Management Controlled By Hardware

    NASA Astrophysics Data System (ADS)

    Douay, N.

    2011-10-01

    In the frame of GALILEO In-Orbit Validation program which is composed of 4 satellites, Thales Alenia Space France has designed, developed and tested the Electrical Power Subsystem. Besides some classical design choices like: -50V regulated main power bus provided by the PCDU manufactured by Terma (DK), -Solar array, manufactured by Dutch-Space (NL), using Ga-As triple junction technology from Azur Space Power Solar GmbH, -SAFT (FR) Lithium-ion Battery for which cell package balancing function is required, -Solar Array Drive Mechanism, provided by RUAG Space Switzerland, to transfer the power. This subsystem features a fully autonomous, failure tolerant, battery charge management able to operate even after a complete unavailability of the on-board software. The battery charge management is implemented such that priority is always given to satisfy the satellite main bus needs in order to maintain the main bus regulation under MEA control. This battery charge management principle provides very high reliability and operational robustness. So, the paper describes : -the battery charge management concept using a combination of PCDU hardware and relevant battery lines monitoring, -the functional aspect of the single point failure free S4R (Sequential Switching Shunt Switch Regulator) and associated performances, -the failure modes isolated and passivated by this architecture. The paper will address as well the autonomous balancing function characteristics and performances.

  20. Redundant mechanisms to form silent chromatin at pericentromeric regions rely on BEND3 and DNA methylation.

    PubMed

    Saksouk, Nehmé; Barth, Teresa K; Ziegler-Birling, Celine; Olova, Nelly; Nowak, Agnieszka; Rey, Elodie; Mateos-Langerak, Julio; Urbach, Serge; Reik, Wolf; Torres-Padilla, Maria-Elena; Imhof, Axel; Déjardin, Jérome; Simboeck, Elisabeth

    2014-11-20

    Constitutive heterochromatin is typically defined by high levels of DNA methylation and H3 lysine 9 trimethylation (H3K9Me3), whereas facultative heterochromatin displays DNA hypomethylation and high H3 lysine 27 trimethylation (H3K27Me3). The two chromatin types generally do not coexist at the same loci, suggesting mutual exclusivity. During development or in cancer, pericentromeric regions can adopt either epigenetic state, but the switching mechanism is unknown. We used a quantitative locus purification method to characterize changes in pericentromeric chromatin-associated proteins in mouse embryonic stem cells deficient for either the methyltransferases required for DNA methylation or H3K9Me3. DNA methylation controls heterochromatin architecture and inhibits Polycomb recruitment. BEND3, a protein enriched on pericentromeric chromatin in the absence of DNA methylation or H3K9Me3, allows Polycomb recruitment and H3K27Me3, resulting in a redundant pathway to generate repressive chromatin. This suggests that BEND3 is a key factor in mediating a switch from constitutive to facultative heterochromatin.

  1. Ants learn to rely on more informative attributes during decision-making.

    PubMed

    Sasaki, Takao; Pratt, Stephen C

    2013-01-01

    Evolutionary theory predicts that animals act to maximize their fitness when choosing among a set of options, such as what to eat or where to live. Making the best choice is challenging when options vary in multiple attributes, and animals have evolved a variety of heuristics to simplify the task. Many of these involve ranking or weighting attributes according to their importance. Because the importance of attributes can vary across time and place, animals might benefit by adjusting weights accordingly. Here, we show that colonies of the ant Temnothorax rugatulus use their experience during nest site selection to increase weights on more informative nest attributes. These ants choose their rock crevice nests on the basis of multiple features. After exposure to an environment where only one attribute differentiated options, colonies increased their reliance on this attribute relative to a second attribute. Although many species show experience-based changes in selectivity based on a single feature, this is the first evidence in animals for adaptive changes in the weighting of multiple attributes. These results show that animal collectives, like individuals, change decision-making strategies according to experience. We discuss how these colony-level changes might emerge from individual behaviour.

  2. Efficient peroxydisulfate activation process not relying on sulfate radical generation for water pollutant degradation.

    PubMed

    Zhang, Tao; Chen, Yin; Wang, Yuru; Le Roux, Julien; Yang, Yang; Croué, Jean-Philippe

    2014-05-20

    Peroxydisulfate (PDS) is an appealing oxidant for contaminated groundwater and toxic industrial wastewaters. Activation of PDS is necessary for application because of its low reactivity. Present activation processes always generate sulfate radicals as actual oxidants which unselectively oxidize organics and halide anions reducing oxidation capacity of PDS and producing toxic halogenated products. Here we report that copper oxide (CuO) can efficiently activate PDS under mild conditions without producing sulfate radicals. The PDS/CuO coupled process is most efficient at neutral pH for decomposing a model compound, 2,4-dichlorophenol (2,4-DCP). In a continuous-flow reaction with an empty-bed contact time of 0.55 min, over 90% of 2,4-DCP (initially 20 μM) and 90% of adsorbable organic chlorine (AOCl) can be removed at the PDS/2,4-DCP molar ratio of 1 and 4, respectively. Based on kinetic study and surface characterization, PDS is proposed to be first activated by CuO through outer-sphere interaction, the rate-limiting step, followed by a rapid reaction with 2,4-DCP present in the solution. In the presence of ubiquitous chloride ions in groundwater/industrial wastewater, the PDS/CuO oxidation shows significant advantages over sulfate radical oxidation by achieving much higher 2,4-DCP degradation capacity and avoiding the formation of highly chlorinated degradation products. This work provides a new way of PDS activation for contaminant removal. PMID:24779765

  3. Seed abscission and fruit dehiscence required for seed dispersal rely on similar genetic networks.

    PubMed

    Balanzà, Vicente; Roig-Villanova, Irma; Di Marzo, Maurizio; Masiero, Simona; Colombo, Lucia

    2016-09-15

    Seed dispersal is an essential trait that enables colonization of new favorable habitats, ensuring species survival. In plants with dehiscent fruits, such as Arabidopsis, seed dispersal depends on two processes: the separation of the fruit valves that protect the seeds (fruit dehiscence) and the detachment of the seeds from the funiculus connecting them to the mother plant (seed abscission). The key factors required to establish a proper lignin pattern for fruit dehiscence are SHATTERPROOF 1 and 2 (SHP1 and SHP2). Here, we demonstrate that the SHP-related gene SEEDSTICK (STK) is a key factor required to establish the proper lignin pattern in the seed abscission zone but in an opposite way. We show that STK acts as a repressor of lignin deposition in the seed abscission zone through the direct repression of HECATE3, whereas the SHP proteins promote lignin deposition in the valve margins by activating INDEHISCENT. The interaction of STK with the SEUSS co-repressor determines the difference in the way STK and SHP proteins control the lignification patterns. Despite this difference in the molecular control of lignification during seed abscission and fruit dehiscence, we show that the genetic networks regulating these two developmental pathways are highly conserved.

  4. Persistent cell migration and adhesion rely on retrograde transport of β(1) integrin.

    PubMed

    Shafaq-Zadah, Massiullah; Gomes-Santos, Carina S; Bardin, Sabine; Maiuri, Paolo; Maurin, Mathieu; Iranzo, Julian; Gautreau, Alexis; Lamaze, Christophe; Caswell, Patrick; Goud, Bruno; Johannes, Ludger

    2016-01-01

    Integrins have key functions in cell adhesion and migration. How integrins are dynamically relocalized to the leading edge in highly polarized migratory cells has remained unexplored. Here, we demonstrate that β1 integrin (known as PAT-3 in Caenorhabditis elegans), but not β3, is transported from the plasma membrane to the trans-Golgi network, to be resecreted in a polarized manner. This retrograde trafficking is restricted to the non-ligand-bound conformation of β1 integrin. Retrograde trafficking inhibition abrogates several β1-integrin-specific functions such as cell adhesion in early embryonic development of mice, and persistent cell migration in the developing posterior gonad arm of C. elegans. Our results establish a paradigm according to which retrograde trafficking, and not endosomal recycling, is the key driver for β1 integrin function in highly polarized cells. These data more generally suggest that the retrograde route is used to relocalize plasma membrane machinery from previous sites of function to the leading edge of migratory cells. PMID:26641717

  5. An Esterification Kinetics Experiment that Relies on the Sense of Smell

    ERIC Educational Resources Information Center

    Bromfield-Lee, Deborah C.; Oliver-Hoyo, Maria T.

    2009-01-01

    This experiment involves an esterification synthesis to study reaction kinetics where students explore these topics utilizing the sense of smell rather than the traditional approach of using spectroscopic methods. Students study the effects of various factors including the concentration of the carboxylic acid and the amounts of the catalyst or…

  6. A Multiple-Choice Mushroom: Schools, Colleges Rely More than Ever on Standardized Tests.

    ERIC Educational Resources Information Center

    Hawkins, B. Denise

    1995-01-01

    This discussion of college entrance examinations reviews differences between the Scholastic Assessment Test (SAT) and the American College Test. It then focuses on the SAT, discussing numbers of students taking the tests, changes in test construction to recognize contributions of women and minorities, involvement of African Americans in…

  7. Microsporidia Intracellular Development Relies on Myc Interaction Network Transcription Factors in the Host.

    PubMed

    Botts, Michael R; Cohen, Lianne B; Probert, Christopher S; Wu, Fengting; Troemel, Emily R

    2016-01-01

    Microsporidia are ubiquitous parasites that infect a wide range of animal hosts, and these fungal-related microbes undergo their entire replicative lifecycle inside of host cells. Despite being widespread in the environment and causing medical and agricultural harm, virtually nothing is known about the host factors important to facilitate their growth and development inside of host cells. Here, we perform a genetic screen to identify host transcription factors important for development of the microsporidian pathogen Nematocida parisii inside intestinal cells of its natural host, the nematode Caenorhabditis elegans Through this screen, we identified the C. elegans Myc family of transcription factors as key host regulators of microsporidia growth and development. The Mad-like transcription factor MDL-1, and the Max-like transcription factors MXL-1 and MXL-2 promote pathogen levels, while the Myc-Mondo-like transcription factor MML-1 inhibits pathogen levels. We used epistasis analysis to show that MDL-1 and MXL-1, which are thought to function as a heterodimer, appear to be acting canonically. In contrast, MXL-2 and MML-1, which are also thought to function as a heterodimer, appear to be acting in separate pathways (noncanonically) in the context of pathogen infection. We also found that both MDL-1::GFP and MML-1::GFP are expressed in intestinal cells during infection. These findings provide novel insight into the host transcription factors that regulate microsporidia development. PMID:27402359

  8. Redundant mechanisms to form silent chromatin at pericentromeric regions rely on BEND3 and DNA methylation.

    PubMed

    Saksouk, Nehmé; Barth, Teresa K; Ziegler-Birling, Celine; Olova, Nelly; Nowak, Agnieszka; Rey, Elodie; Mateos-Langerak, Julio; Urbach, Serge; Reik, Wolf; Torres-Padilla, Maria-Elena; Imhof, Axel; Déjardin, Jérome; Simboeck, Elisabeth

    2014-11-20

    Constitutive heterochromatin is typically defined by high levels of DNA methylation and H3 lysine 9 trimethylation (H3K9Me3), whereas facultative heterochromatin displays DNA hypomethylation and high H3 lysine 27 trimethylation (H3K27Me3). The two chromatin types generally do not coexist at the same loci, suggesting mutual exclusivity. During development or in cancer, pericentromeric regions can adopt either epigenetic state, but the switching mechanism is unknown. We used a quantitative locus purification method to characterize changes in pericentromeric chromatin-associated proteins in mouse embryonic stem cells deficient for either the methyltransferases required for DNA methylation or H3K9Me3. DNA methylation controls heterochromatin architecture and inhibits Polycomb recruitment. BEND3, a protein enriched on pericentromeric chromatin in the absence of DNA methylation or H3K9Me3, allows Polycomb recruitment and H3K27Me3, resulting in a redundant pathway to generate repressive chromatin. This suggests that BEND3 is a key factor in mediating a switch from constitutive to facultative heterochromatin. PMID:25457167

  9. 76 FR 69545 - Conditions and Requirements for Relying on Component Part Testing or Certification, or Another...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... the Federal Register of May 20, 2010 (75 FR 28208), we published a proposed rule that would establish... are the risks and benefits of allowing such an arrangement? 75 FR at 28209. (Comment 1)--Some... for issuing their finished product certificates (75 FR 28209). The final rule allows this...

  10. Acoustic duetting in Drosophila virilis relies on the integration of auditory and tactile signals

    PubMed Central

    LaRue, Kelly M; Clemens, Jan; Berman, Gordon J; Murthy, Mala

    2015-01-01

    Many animal species, including insects, are capable of acoustic duetting, a complex social behavior in which males and females tightly control the rate and timing of their courtship song syllables relative to each other. The mechanisms underlying duetting remain largely unknown across model systems. Most studies of duetting focus exclusively on acoustic interactions, but the use of multisensory cues should aid in coordinating behavior between individuals. To test this hypothesis, we develop Drosophila virilis as a new model for studies of duetting. By combining sensory manipulations, quantitative behavioral assays, and statistical modeling, we show that virilis females combine precisely timed auditory and tactile cues to drive song production and duetting. Tactile cues delivered to the abdomen and genitalia play the larger role in females, as even headless females continue to coordinate song production with courting males. These data, therefore, reveal a novel, non-acoustic, mechanism for acoustic duetting. Finally, our results indicate that female-duetting circuits are not sexually differentiated, as males can also produce ‘female-like’ duets in a context-dependent manner. DOI: http://dx.doi.org/10.7554/eLife.07277.001 PMID:26046297

  11. The Achievement Gap: Should We Rely on SAT Scores to Tell Us Anything about It?

    ERIC Educational Resources Information Center

    Whittington, Dale

    2004-01-01

    Increasing numbers of students taking the SAT have declined to identify their race/ethnicity. I examined the impact of non-respondents on the validity of reported racial/ethnic differences and year-to-year changes in test performance. Using an analysis reported by Wainer (1988) and SAT data from 1996 to 2003, I confirmed Wainer's findings that…

  12. Towards improved exact exchange functionals relying on G W quasiparticle methods for parametrization

    NASA Astrophysics Data System (ADS)

    Zólyomi, V.; Kürti, J.

    2015-07-01

    We use fully self-consistent GW calculations on diamond and silicon carbide to reparametrize the Heyd-Scuseria-Ernzerhof (HSE) exact exchange density functional for use in band structure calculations of semiconductors and insulators. We show that the thus modified functional is able to calculate the band structure of bulk Si, Ge, GaAs, and CdTe with good quantitative accuracy at a significantly reduced computational cost as compared to G W methods, and also gives significantly improved band gap predictions in wide-gap ionic crystals as compared to the HSE06 parametrization. We discuss the limitations of this functional in low dimensions by calculating the band structures of single-layer hexagonal BN and MoS2, and by demonstrating that the diameter scaling of curvature induced band gaps in single-walled carbon nanotubes is still physically incorrect using our functional; we consider possible remedies to this problem.

  13. First N-Heterocyclic Carbenes Relying on the Triazolone Structural Motif: Syntheses, Modifications and Reactivity.

    PubMed

    Jonek, Markus; Diekmann, Janina; Ganter, Christian

    2015-10-26

    4-Phenylsemicarbazide and 1,5-diphenylcarbazide are suitable starting materials for the syntheses of N-heterocyclic carbene (NHC) compounds with new backbone structures. In the first case, cyclisation and subsequent methylation leads to a cationic precursor whose deprotonation affords the triazolon-ylidene 2, which was converted to the corresponding sulfur and selenium adducts and a range of metal complexes. In contrast, cyclisation of diphenylcarbazide affords a neutral betain-type NHC-precursor 7, which is not in equilibrium with its carbene tautomer 7a. Precursor 7 can either be deprotonated to give the anionic NHC 8 or methylated at the N or O atom of the backbone resulting in two isomeric cationic species 16 and 20. Deprotonation of the latter two provides neutral NHC compounds with a carboxamide or carboximidate backbone, respectively. The ligand properties of the new NHC compounds were evaluated by IR and (77) Se NMR spectroscopy. Tolman electronic parameter (TEP) values range from 2050 to 2063 cm(-1) with the anionic NHC 8 being the best overall donor. PMID:26395132

  14. Neuroprotective Effects of 17β-Estradiol Rely on Estrogen Receptor Membrane Initiated Signals

    PubMed Central

    Fiocchetti, Marco; Ascenzi, Paolo; Marino, Maria

    2012-01-01

    Besides its crucial role in many physiological events, 17β-estradiol (E2) exerts protective effects in the central nervous system. The E2 effects are not restricted to the brain areas related with the control of reproductive function, but rather are widespread throughout the developing and the adult brain. E2 actions are mediated through estrogen receptors (i.e., ERα and ERβ) belonging to the nuclear receptor super-family. As members of the ligand-regulated transcription factor family, classically, the actions of ERs in the brain were thought to mediate only the E2 long-term transcriptional effects. However, a growing body of evidence highlighted rapid, membrane initiated E2 effects in the brain that are independent of ER transcriptional activities and are involved in E2-induced neuroprotection. The aim of this review is to focus on the rapid effects of E2 in the brain highlighting the specific role of the signaling pathway(s) of the ERβ subtype in the neuroprotective actions of E2. PMID:22493583

  15. Dynamic signaling in the Hog1 MAPK pathway relies on high basal signal transduction.

    PubMed

    Macia, Javier; Regot, Sergi; Peeters, Tom; Conde, Núria; Solé, Ricard; Posas, Francesc

    2009-01-01

    Appropriate regulation of the Hog1 mitogen-activated protein kinase (MAPK) pathway is essential for cells to survive osmotic stress. Here, we show that the two sensing mechanisms upstream of Hog1 display different signaling properties. The Sho1 branch is an inducible nonbasal system, whereas the Sln1 branch shows high basal signaling that is restricted by a MAPK-mediated feedback mechanism. A two-dimensional mathematical model of the Snl1 branch, including high basal signaling and a Hog1-regulated negative feedback, shows that a system with basal signaling exhibits higher efficiency, with faster response times and higher sensitivity to variations in external signals, than would systems without basal signaling. Analysis of two other yeast MAPK pathways, the Fus3 and Kss1 signaling pathways, indicates that high intrinsic basal signaling may be a general property of MAPK pathways allowing rapid and sensitive responses to environmental changes. PMID:19318625

  16. Microsporidia Intracellular Development Relies on Myc Interaction Network Transcription Factors in the Host

    PubMed Central

    Botts, Michael R.; Cohen, Lianne B.; Probert, Christopher S.; Wu, Fengting; Troemel, Emily R.

    2016-01-01

    Microsporidia are ubiquitous parasites that infect a wide range of animal hosts, and these fungal-related microbes undergo their entire replicative lifecycle inside of host cells. Despite being widespread in the environment and causing medical and agricultural harm, virtually nothing is known about the host factors important to facilitate their growth and development inside of host cells. Here, we perform a genetic screen to identify host transcription factors important for development of the microsporidian pathogen Nematocida parisii inside intestinal cells of its natural host, the nematode Caenorhabditis elegans. Through this screen, we identified the C. elegans Myc family of transcription factors as key host regulators of microsporidia growth and development. The Mad-like transcription factor MDL-1, and the Max-like transcription factors MXL-1 and MXL-2 promote pathogen levels, while the Myc-Mondo-like transcription factor MML-1 inhibits pathogen levels. We used epistasis analysis to show that MDL-1 and MXL-1, which are thought to function as a heterodimer, appear to be acting canonically. In contrast, MXL-2 and MML-1, which are also thought to function as a heterodimer, appear to be acting in separate pathways (noncanonically) in the context of pathogen infection. We also found that both MDL-1::GFP and MML-1::GFP are expressed in intestinal cells during infection. These findings provide novel insight into the host transcription factors that regulate microsporidia development. PMID:27402359

  17. Spatial and Temporal Eye–Hand Coordination Relies on the Parietal Reach Region

    PubMed Central

    Hauschild, Markus; Wilke, Melanie; Andersen, Richard A.

    2014-01-01

    Coordinated eye movements are crucial for precision control of our hands. A commonly believed neural mechanism underlying eye–hand coordination is interaction between the neural networks controlling each effector, exchanging, and matching information, such as movement target location and onset time. Alternatively, eye–hand coordination may result simply from common inputs to independent eye and hand control pathways. Thus far, it remains unknown whether and where either of these two possible mechanisms exists. A candidate location for the former mechanism, interpathway communication, includes the posterior parietal cortex (PPC) where distinct effector-specific areas reside. If the PPC were within the network for eye–hand coordination, perturbing it would affect both eye and hand movements that are concurrently planned. In contrast, if eye–hand coordination arises solely from common inputs, perturbing one effector pathway, e.g., the parietal reach region (PRR), would not affect the other effector. To test these hypotheses, we inactivated part of PRR in the macaque, located in the medial bank of the intraparietal sulcus encompassing the medial intraparietal area and area 5V. When each effector moved alone, PRR inactivation shortened reach but not saccade amplitudes, compatible with the known reach-selective activity of PRR. However, when both effectors moved concurrently, PRR inactivation shortened both reach and saccade amplitudes, and decoupled their reaction times. Therefore, consistent with the interpathway communication hypothesis, we propose that the planning of concurrent eye and hand movements causes the spatial information in PRR to influence the otherwise independent eye control pathways, and that their temporal coupling requires an intact PRR. PMID:25232123

  18. Wild hummingbirds rely on landmarks not geometry when learning an array of flowers.

    PubMed

    Hurly, T Andrew; Fox, Thomas A O; Zwueste, Danielle M; Healy, Susan D

    2014-09-01

    Rats, birds or fish trained to find a reward in one corner of a small enclosure tend to learn the location of the reward using both nearby visual features and the geometric relationships of corners and walls. Because these studies are conducted under laboratory and thereby unnatural conditions, we sought to determine whether wild, free-living rufous hummingbirds (Selasphorus rufus) learning a single reward location within a rectangular array of flowers would similarly employ both nearby visual landmarks and the geometric relationships of the array. Once subjects had learned the location of the reward, we used test probes in which one or two experimental landmarks were moved or removed in order to reveal how the birds remembered the reward location. The hummingbirds showed no evidence that they used the geometry of the rectangular array of flowers to remember the reward. Rather, they used our experimental landmarks, and possibly nearby, natural landmarks, to orient and navigate to the reward. We believe this to be the first test of the use of rectangular geometry by wild animals, and we recommend further studies be conducted in ecologically relevant conditions in order to help determine how and when animals form complex geometric representations of their local environments.

  19. Polymerase gamma mutator mice rely on increased glycolytic flux for energy production.

    PubMed

    Saleem, Ayesha; Safdar, Adeel; Kitaoka, Yu; Ma, Xiaoxing; Marquez, Olivia S; Akhtar, Mahmood; Nazli, Aisha; Suri, Rahul; Turnbull, John; Tarnopolsky, Mark A

    2015-03-01

    Several studies have illustrated that the polymerase gamma mutator (PolG) mice have reduced mitochondrial content secondary to systemic mitochondrial dysfunction, and subsequently a lower capacity to perform aerobic respiration and endurance exercise. We sought to delineate the extent of glycolysis as a means of energy production in the PolG mice in the absence of optimal mitochondrial function. PolG mice display an enhanced reliance on glycolysis as compared to their wild-type counterparts. This is evident by the resting hypoglycemia, higher PFK content, and elevated plasma lactate levels in the PolG mice. In vitro experiments provide further proof that PolG derived dermal fibroblasts have a higher rate of, and capacity for, glycolysis. PolG mice also have enhanced capacity to perform hepatic gluconeogenesis that is likely enhancing the Cori cycle capacity.

  20. Microsporidia Intracellular Development Relies on Myc Interaction Network Transcription Factors in the Host.

    PubMed

    Botts, Michael R; Cohen, Lianne B; Probert, Christopher S; Wu, Fengting; Troemel, Emily R

    2016-01-01

    Microsporidia are ubiquitous parasites that infect a wide range of animal hosts, and these fungal-related microbes undergo their entire replicative lifecycle inside of host cells. Despite being widespread in the environment and causing medical and agricultural harm, virtually nothing is known about the host factors important to facilitate their growth and development inside of host cells. Here, we perform a genetic screen to identify host transcription factors important for development of the microsporidian pathogen Nematocida parisii inside intestinal cells of its natural host, the nematode Caenorhabditis elegans Through this screen, we identified the C. elegans Myc family of transcription factors as key host regulators of microsporidia growth and development. The Mad-like transcription factor MDL-1, and the Max-like transcription factors MXL-1 and MXL-2 promote pathogen levels, while the Myc-Mondo-like transcription factor MML-1 inhibits pathogen levels. We used epistasis analysis to show that MDL-1 and MXL-1, which are thought to function as a heterodimer, appear to be acting canonically. In contrast, MXL-2 and MML-1, which are also thought to function as a heterodimer, appear to be acting in separate pathways (noncanonically) in the context of pathogen infection. We also found that both MDL-1::GFP and MML-1::GFP are expressed in intestinal cells during infection. These findings provide novel insight into the host transcription factors that regulate microsporidia development.

  1. Delayed cardiomyopathy in dystrophin deficient mdx mice relies on intrinsic glutathione resource.

    PubMed

    Khouzami, Lara; Bourin, Marie-Claude; Christov, Christo; Damy, Thibaud; Escoubet, Brigitte; Caramelle, Philippe; Perier, Magali; Wahbi, Karim; Meune, Christophe; Pavoine, Catherine; Pecker, Françoise

    2010-09-01

    Oxidative stress contributes to the pathogenesis of Duchenne muscular dystrophy (DMD). Although they have been a model for DMD, mdx mice exhibit slowly developing cardiomyopathy. We hypothesized that disease process was delayed owing to the development of an adaptive mechanism against oxidative stress, involving glutathione synthesis. At 15 to 20 weeks of age, mdx mice displayed a 33% increase in blood glutathione levels compared with age-matched C57BL/6 mice. In contrast, cardiac glutathione content was similar in mdx and C57BL/6 mice as a result of the balanced increased expression of glutamate cysteine ligase catalytic and regulatory subunits ensuring glutathione synthesis in the mdx mouse heart, as well as increased glutathione peroxidase-1 using glutathione. Oral administration from 10 weeks of age of the glutamate cysteine ligase inhibitor, l-buthionine(S,R)-sulfoximine (BSO, 5 mmol/L), led to a 33% and 50% drop in blood and cardiac glutathione, respectively, in 15- to 20-week-old mdx mice. Moreover, 20-week-old BSO-treated mdx mice displayed left ventricular hypertrophy associated with diastolic dysfunction, discontinuities in beta-dystroglycan expression, micronecrosis and microangiopathic injuries. Examination of the glutathione status in four DMD patients showed that three displayed systemic glutathione deficiency as well. In conclusion, low glutathione resource hastens the onset of cardiomyopathy linked to a defect in dystrophin in mdx mice. This is relevant to the glutathione deficiency that DMD patients may suffer.

  2. Delayed Cardiomyopathy in Dystrophin Deficient mdx Mice Relies on Intrinsic Glutathione Resource

    PubMed Central

    Khouzami, Lara; Bourin, Marie-Claude; Christov, Christo; Damy, Thibaud; Escoubet, Brigitte; Caramelle, Philippe; Perier, Magali; Wahbi, Karim; Meune, Christophe; Pavoine, Catherine; Pecker, Françoise

    2010-01-01

    Oxidative stress contributes to the pathogenesis of Duchenne muscular dystrophy (DMD). Although they have been a model for DMD, mdx mice exhibit slowly developing cardiomyopathy. We hypothesized that disease process was delayed owing to the development of an adaptive mechanism against oxidative stress, involving glutathione synthesis. At 15 to 20 weeks of age, mdx mice displayed a 33% increase in blood glutathione levels compared with age-matched C57BL/6 mice. In contrast, cardiac glutathione content was similar in mdx and C57BL/6 mice as a result of the balanced increased expression of glutamate cysteine ligase catalytic and regulatory subunits ensuring glutathione synthesis in the mdx mouse heart, as well as increased glutathione peroxidase-1 using glutathione. Oral administration from 10 weeks of age of the glutamate cysteine ligase inhibitor, l-buthionine(S,R)-sulfoximine (BSO, 5 mmol/L), led to a 33% and 50% drop in blood and cardiac glutathione, respectively, in 15- to 20-week-old mdx mice. Moreover, 20-week-old BSO-treated mdx mice displayed left ventricular hypertrophy associated with diastolic dysfunction, discontinuities in β-dystroglycan expression, micronecrosis and microangiopathic injuries. Examination of the glutathione status in four DMD patients showed that three displayed systemic glutathione deficiency as well. In conclusion, low glutathione resource hastens the onset of cardiomyopathy linked to a defect in dystrophin in mdx mice. This is relevant to the glutathione deficiency that DMD patients may suffer. PMID:20696779

  3. Persistent identifiers for web service requests relying on a provenance ontology design pattern

    NASA Astrophysics Data System (ADS)

    Car, Nicholas; Wang, Jingbo; Wyborn, Lesley; Si, Wei

    2016-04-01

    Delivering provenance information for datasets produced from static inputs is relatively straightforward: we represent the processing actions and data flow using provenance ontologies and link to stored copies of the inputs stored in repositories. If appropriate detail is given, the provenance information can then describe what actions have occurred (transparency) and enable reproducibility. When web service-generated data is used by a process to create a dataset instead of a static inputs, we need to use sophisticated provenance representations of the web service request as we can no longer just link to data stored in a repository. A graph-based provenance representation, such as the W3C's PROV standard, can be used to model the web service request as a single conceptual dataset and also as a small workflow with a number of components within the same provenance report. This dual representation does more than just allow simplified or detailed views of a dataset's production to be used where appropriate. It also allow persistent identifiers to be assigned to instances of a web service requests, thus enabling one form of dynamic data citation, and for those identifiers to resolve to whatever level of detail implementers think appropriate in order for that web service request to be reproduced. In this presentation we detail our reasoning in representing web service requests as small workflows. In outline, this stems from the idea that web service requests are perdurant things and in order to most easily persist knowledge of them for provenance, we should represent them as a nexus of relationships between endurant things, such as datasets and knowledge of particular system types, as these endurant things are far easier to persist. We also describe the ontology design pattern that we use to represent workflows in general and how we apply it to different types of web service requests. We give examples of specific web service requests instances that were made by systems at Australia's National Computing Infrastructure and show how one can 'click' through provenance interfaces to see the dual representations of the requests using provenance management tooling we have built.

  4. Desiccation tolerance in the tardigrade Richtersius coronifer relies on muscle mediated structural reorganization.

    PubMed

    Halberg, Kenneth Agerlin; Jørgensen, Aslak; Møbjerg, Nadja

    2013-01-01

    Life unfolds within a framework of constraining abiotic factors, yet some organisms are adapted to handle large fluctuations in physical and chemical parameters. Tardigrades are microscopic ecdysozoans well known for their ability to endure hostile conditions, such as complete desiccation--a phenomenon called anhydrobiosis. During dehydration, anhydrobiotic animals undergo a series of anatomical changes. Whether this reorganization is an essential regulated event mediated by active controlled processes, or merely a passive result of the dehydration process, has not been clearly determined. Here, we investigate parameters pivotal to the formation of the so-called "tun", a state that in tardigrades and rotifers marks the entrance into anhydrobiosis. Estimation of body volume in the eutardigrade Richtersius coronifer reveals an 87 % reduction in volume from the hydrated active state to the dehydrated tun state, underlining the structural stress associated with entering anhydrobiosis. Survival experiments with pharmacological inhibitors of mitochondrial energy production and muscle contractions show that i) mitochondrial energy production is a prerequisite for surviving desiccation, ii) uncoupling the mitochondria abolishes tun formation, and iii) inhibiting the musculature impairs the ability to form viable tuns. We moreover provide a comparative analysis of the structural changes involved in tun formation, using a combination of cytochemistry, confocal laser scanning microscopy and 3D reconstructions as well as scanning electron microscopy. Our data reveal that the musculature mediates a structural reorganization vital for anhydrobiotic survival, and furthermore that maintaining structural integrity is essential for resumption of life following rehydration.

  5. Efficient peroxydisulfate activation process not relying on sulfate radical generation for water pollutant degradation.

    PubMed

    Zhang, Tao; Chen, Yin; Wang, Yuru; Le Roux, Julien; Yang, Yang; Croué, Jean-Philippe

    2014-05-20

    Peroxydisulfate (PDS) is an appealing oxidant for contaminated groundwater and toxic industrial wastewaters. Activation of PDS is necessary for application because of its low reactivity. Present activation processes always generate sulfate radicals as actual oxidants which unselectively oxidize organics and halide anions reducing oxidation capacity of PDS and producing toxic halogenated products. Here we report that copper oxide (CuO) can efficiently activate PDS under mild conditions without producing sulfate radicals. The PDS/CuO coupled process is most efficient at neutral pH for decomposing a model compound, 2,4-dichlorophenol (2,4-DCP). In a continuous-flow reaction with an empty-bed contact time of 0.55 min, over 90% of 2,4-DCP (initially 20 μM) and 90% of adsorbable organic chlorine (AOCl) can be removed at the PDS/2,4-DCP molar ratio of 1 and 4, respectively. Based on kinetic study and surface characterization, PDS is proposed to be first activated by CuO through outer-sphere interaction, the rate-limiting step, followed by a rapid reaction with 2,4-DCP present in the solution. In the presence of ubiquitous chloride ions in groundwater/industrial wastewater, the PDS/CuO oxidation shows significant advantages over sulfate radical oxidation by achieving much higher 2,4-DCP degradation capacity and avoiding the formation of highly chlorinated degradation products. This work provides a new way of PDS activation for contaminant removal.

  6. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon.

    PubMed Central

    Weinberg, C R

    1995-01-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of alpha-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining alpha-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting "measurement confounding" can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. Images Figure 1. Figure 2. Figure 3. Figure 4. PMID:8605854

  7. Brucella Intracellular Life Relies on the Transmembrane Protein CD98 Heavy Chain.

    PubMed

    Keriel, Anne; Botella, Eric; Estrach, Soline; Bragagnolo, Gabriel; Vergunst, Annette C; Feral, Chloe C; O'Callaghan, David

    2015-06-01

    Brucella are intracellular bacterial pathogens that use a type IV secretion system (T4SS) to escape host defenses and create a niche in which they can multiply. Although the importance of Brucella T4SS is clear, little is known about its interactions with host cell structures. In this study, we identified the eukaryotic protein CD98hc as a partner for Brucella T4SS subunit VirB2. This transmembrane glycoprotein is involved in amino acid transport, modulation of integrin signaling, and cell-to-cell fusion. Knockdown of CD98hc expression in HeLa cells demonstrated that it is essential for Brucella infection. Using knockout dermal fibroblasts, we confirmed its role for Brucella but found that it is not required for Salmonella infection. CD98hc transiently accumulates around the bacteria during the early phases of infection and is required for both optimal bacterial uptake and intracellular multiplication of Brucella. These results provide new insights into the complex interplay between Brucella and its host.

  8. Desert ants do not rely on sky compass information for the perception of inclined path segments.

    PubMed

    Hess, Doreen; Koch, Julja; Ronacher, Bernhard

    2009-05-01

    On their foraging excursions, desert ants (Cataglyphis fortis) navigate by means of path integration, exhibiting high precision even in undulating terrain. To avoid errors in their home vector the ants must measure the slopes of ascents and descents in their itinerary. This information is necessary to convert the distances actually walked on the slopes into the ground distance, which is the crucial parameter for vector navigation. However, it is as yet unknown how Cataglyphis perceives the slopes of inclines. We asked whether the ants gauge slopes by means of the changes in the sky's polarization pattern or the sun's position imposed by the unusual head posture when walking on inclines. During training on a ramp, we manipulated the sky compass cues available for the ants. If both sky compass cues, polarization pattern and sun position, were excluded during ramp training, the ants behaved in subsequent tests as if they had never encountered a slope. However, the presence of either of the two compass cues was sufficient for the ants to memorize the sloped path segment. In a third experiment, the supposed polarization cue was excluded by covering the training and test channels with a linear polarization filter. In these tests the ants clearly showed that they had perceived and memorized an ascent also without a change in the polarization pattern. Hence, changes in polarization perception can be ruled out as the crucial cue for gauging slopes, and we conclude that slopes are monitored by a, still unknown, proprioceptive mechanism.

  9. Hearing silences: human auditory processing relies on preactivation of sound-specific brain activity patterns.

    PubMed

    SanMiguel, Iria; Widmann, Andreas; Bendixen, Alexandra; Trujillo-Barreto, Nelson; Schröger, Erich

    2013-05-15

    The remarkable capabilities displayed by humans in making sense of an overwhelming amount of sensory information cannot be explained easily if perception is viewed as a passive process. Current theoretical and computational models assume that to achieve meaningful and coherent perception, the human brain must anticipate upcoming stimulation. But how are upcoming stimuli predicted in the brain? We unmasked the neural representation of a prediction by omitting the predicted sensory input. Electrophysiological brain signals showed that when a clear prediction can be formulated, the brain activates a template of its response to the predicted stimulus before it arrives to our senses.

  10. Monkeys Rely on Recency of Stimulus Repetition When Solving Short-Term Memory Tasks

    ERIC Educational Resources Information Center

    Wittig, John H., Jr.; Richmond, Barry J.

    2014-01-01

    Seven monkeys performed variants of two short-term memory tasks that others have used to differentiate between selective and nonselective memory mechanisms. The first task was to view a list of sequentially presented images and identify whether a test matched any image from the list, but not a distractor from a preceding list. Performance was best…

  11. Detecting Bias in Meta-Analyses of Distance Education Research: Big Pictures We Can Rely On

    ERIC Educational Resources Information Center

    Bernard, Robert M.; Borokhovski, Eugene; Tamim, Rana M.

    2014-01-01

    This article has two interrelated purposes. The first is to explain how various forms of bias, if introduced during any stage of a meta-analysis, can provide the consumer with a misimpression of the state of a research literature. Five of the most important bias-producing aspects of a meta-analysis are presented and discussed. Second, armed with…

  12. Relying on fin erosion to identify hatchery-reared brown trout in a Tennessee river

    USGS Publications Warehouse

    Meerbeek, Jonathan R.; Bettoli, Phillip William

    2012-01-01

    Hatchery-induced fin erosion can be used to identify recently stocked catchable-size brown trout Salmo trutta during annual surveys to qualitatively estimate contributions to a fishery. However, little is known about the longevity of this mark and its effectiveness as a short-term (≤ 1 year) mass-marking technique. We evaluated hatchery-induced pectoral fin erosion as a mass-marking technique for short-term stocking evaluations by stocking microtagged brown trout in a tailwater and repeatedly sampling those fish to observe and measure their pectoral fins. At Dale Hollow National Fish Hatchery, 99.1% (228 of 230) of microtagged brown trout in outdoor concrete raceways had eroded pectoral fins 1 d prior to stocking. Between 34 and 68 microtagged and 26-35 wild brown trout were collected during eight subsequent electrofishing samples. In a blind test based on visual examination of pectoral fins at up to 322 d poststocking, one observer correctly identified 91.7% to 100.0% (mean of 96.9%) of microtagged brown trout prior to checking for microtags. In the laboratory, pectoral fin length and width measurements were recorded to statistically compare the fin measurements of wild and microtagged hatchery brown trout. With only one exception, all pectoral fin measurements on each date averaged significantly larger for wild trout than for microtagged brown trout. Based on the number of pectoral fin measurements falling below 95% prediction intervals, 93.7% (148 of 158) of microtagged trout were correctly identified as hatchery fish based on regression models up to 160 d poststocking. Only 72.2% (70 of 97) of microtagged trout were identified correctly after 160 d based on pectoral fin measurements and the regression models. We concluded that visual examination of pectoral fin erosion was a very effective way to identify stocked brown trout for up to 322 d poststocking.

  13. Galectin-3-induced cell spreading and motility relies on distinct signaling mechanisms compared to fibronectin.

    PubMed

    More, Shyam K; Chiplunkar, Shubhada V; Kalraiya, Rajiv D

    2016-05-01

    Secreted galectin-3 often gets incorporated into extracellular matrix and is utilized by cancer cells for spreading, movement, and metastatic dissemination. Here we investigate molecular mechanisms by which galectin-3 brings about these effects and compare it with fibronectin. Imaging of cells spread on fibronectin showed stress fibers throughout cell body, however, galectin-3-induced formation of parallel actin bundles in the lamellipodial region resulting in unique morphological features. FRAP analysis showed that the actin turnover in the lamellipodial region was much higher in cells spread on galectin-3 as compared to that on fibronectin. Rac1 activation is correlated with lamellipodial organization on both the substrates. Activation of Akt and Rac1, the regulators of actin dynamics, show inverse correlation with each other on both galectin-3 and fibronectin. Activation of Erk however, remained similar. Further, inhibition of activation of Akt and Erk inhibited spreading and motility of cells on galectin-3 but not on fibronectin. The results very comprehensively demonstrate distinct signaling pathways that regulate microfilament organization, lamellipodial structures, spreading, and movement of cells plated on galectin-3 as opposed to fibronectin.

  14. Plant tolerance to excess light energy and photooxidative damage relies on plastoquinone biosynthesis

    PubMed Central

    Ksas, Brigitte; Becuwe, Noëlle; Chevalier, Anne; Havaux, Michel

    2015-01-01

    Plastoquinone-9 is known as a photosynthetic electron carrier to which has also been attributed a role in the regulation of gene expression and enzyme activities via its redox state. Here, we show that it acts also as an antioxidant in plant leaves, playing a central photoprotective role. When Arabidopsis plants were suddenly exposed to excess light energy, a rapid consumption of plastoquinone-9 occurred, followed by a progressive increase in concentration during the acclimation phase. By overexpressing the plastoquinone-9 biosynthesis gene SPS1 (SOLANESYL DIPHOSPHATE SYNTHASE 1) in Arabidopsis, we succeeded in generating plants that specifically accumulate plastoquinone-9 and its derivative plastochromanol-8. The SPS1-overexpressing lines were much more resistant to photooxidative stress than the wild type, showing marked decreases in leaf bleaching, lipid peroxidation and PSII photoinhibition under excess light. Comparison of the SPS1 overexpressors with other prenyl quinone mutants indicated that the enhanced phototolerance of the former plants is directly related to their increased capacities for plastoquinone-9 biosynthesis. PMID:26039552

  15. Toxoplasma gondii Relies on Both Host and Parasite Isoprenoids and Can Be Rendered Sensitive to Atorvastatin

    PubMed Central

    Li, Zhu-Hong; Ramakrishnan, Srinivasan; Striepen, Boris; Moreno, Silvia N. J.

    2013-01-01

    Intracellular pathogens have complex metabolic interactions with their host cells to ensure a steady supply of energy and anabolic building blocks for rapid growth. Here we use the obligate intracellular parasite Toxoplasma gondii to probe this interaction for isoprenoids, abundant lipidic compounds essential to many cellular processes including signaling, trafficking, energy metabolism, and protein translation. Synthesis of precursors for isoprenoids in Apicomplexa occurs in the apicoplast and is essential. To synthesize longer isoprenoids from these precursors, T. gondii expresses a bifunctional farnesyl diphosphate/geranylgeranyl diphosphate synthase (TgFPPS). In this work we construct and characterize T. gondii null mutants for this enzyme. Surprisingly, these mutants have only a mild growth phenotype and an isoprenoid composition similar to wild type parasites. However, when extracellular, the loss of the enzyme becomes phenotypically apparent. This strongly suggests that intracellular parasite salvage FPP and/or geranylgeranyl diphosphate (GGPP) from the host. We test this hypothesis using inhibitors of host cell isoprenoid synthesis. Mammals use the mevalonate pathway, which is susceptible to statins. We document strong synergy between statin treatment and pharmacological or genetic interference with the parasite isoprenoid pathway. Mice can be cured with atorvastatin (Lipitor) from a lethal infection with the TgFPPs mutant. We propose a double-hit strategy combining inhibitors of host and parasite pathways as a novel therapeutic approach against Apicomplexan parasites. PMID:24146616

  16. Potential pitfalls of relying on hydrogen sulfide (H2S) production to identify Salmonella in feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella can be difficult to assess and isolate in poultry feed due to stress, uneven distribution and poor growth. Previous studies have shown that several strains of Salmonella can be affected by environmental changes, resulting in H2S-negative colonies. This is a major concern, as H2S productio...

  17. Whom Do Centenarians Rely on for Support? Findings From the Second Heidelberg Centenarian Study.

    PubMed

    Boerner, Kathrin; Jopp, Daniela S; Park, Min-Kyung S; Rott, Christoph

    2016-01-01

    This paper provides a detailed picture of the sources and types of informal support available to centenarians, depending on their housing and care arrangements. Participants were 112 centenarians and 96 primary contacts of centenarians enrolled in the population-based Second Heidelberg Centenarian Study. Findings indicate that children of centenarians were their primary source of support in daily life. Those without living children had overall less help. Most frequently reported was help with administrative tasks, regardless of centenarians' residence or living arrangement. All other types of help (e.g., with activities of daily living and housework) were reported by about one-third and were mostly provided by children; centenarians without children were more likely to have friends/neighbors involved in some of these tasks. The one category reported by a third of the centenarians regardless of residence, living arrangements, or presence of a child was help with socializing/companionship. Findings constitute an important step toward identifying and meeting the support needs of centenarians and their families. Policy implications are discussed. PMID:26959657

  18. Outcomes of Extensive Hybridization and Introgression in Epidendrum (Orchidaceae): Can We Rely on Species Boundaries?

    PubMed Central

    Vega, Yesenia; Marques, Isabel; Castro, Sílvia; Loureiro, João

    2013-01-01

    Hybridization has the potential to contribute to phenotypic and genetic variation and can be a major evolutionary mechanism. However, when hybridization is extensive it can also lead to the blurring of species boundaries and the emergence of cryptic species (i.e., two or more species not distinguishable morphologically). In this study, we address this hypothesis in Epidendrum, the largest Neotropical genus of orchids where hybridization is apparently so common that it may explain the high levels of morphological diversity found. Nonetheless, this hypothesis is mostly based on the intermediacy of morphological characters and intermediacy by itself is not a proof of hybridization. Therefore, in this study, we first assessed the existence of hybrids using cpDNA and AFLP data gathered from a large-scale sampling comprising 1038 plants of three species of Epidendrum (E. calanthum, E. cochlidium and E. schistochilum). Subsequently, a Bayesian assignment of individuals into different genetic classes (pure species, F1, F2 or backcross generations) revealed that hybrid genotypes were prevalent in all sympatric populations. In most cases, parental species were not assigned as pure individuals, rather consisting in backcrossed genotypes or F1 hybrids. We also found that reproductive barriers are apparently very weak in Epidendrum because the three species largely overlapped in their flowering periods and interspecific crosses always produced viable seeds. Further, hybridization contributed to enhance floral variability, genome size and reproductive success since we found that these traits were always higher in hybrid classes (F1, F2 and backcrosses) than in pure parental species, and offer an explanation for the blurring of species boundaries in this genus of orchids. We hypothesize that these natural hybrids possess an evolutionary advantage, which may explain the high rates of cryptic species observed in this genus. PMID:24224057

  19. Engineering Signaling Aptamers That Rely on Kinetic Rather Than Equilibrium Competition.

    PubMed

    Du, Yan; Zhen, Shu Jun; Li, Bingling; Byrom, Michelle; Jiang, Yu Sherry; Ellington, Andrew D

    2016-02-16

    During the past decade, aptasensors have largely been designed on the basis of the notion that ligand-modulated equilibration between aptamer conformations could be exploited for sensing. One implementation of this strategy has been to denature the aptamer with an antisense oligonucleotide, wait for dissociation of the antisense oligonucleotide, and stabilize the folded, signaling conformer with a ligand. However, there is a large kinetic barrier associated with releasing the oligonucleotide from the aptamer to again obtain an active, binding conformation. If the length of the antisense oligonucleotide is decreased to make dissociation from the aptamer more favorable, higher background signals are observed. To improve the general methodology for developing aptasensors, we have developed a novel and robust strategy for aptasensor design in which an oligonucleotide kinetically competes with the ligand for binding rather than having to be released from a stable duplex. While the oligonucleotide can induce conformational change, it initially chooses between the aptamer and a molecular beacon (MB), a process that does not require a lengthy pre-equilibration. Using an anti-ricin aptamer as a starting point, we developed a "competitive" aptasensor with a measured limit of detection (LOD) of 30 nM with an optical readout and as low as 3 nM for ricin toxin A-chain (RTA) detection on an electrochemical platform.

  20. Paper-Based Analytical Devices Relying on Visible-Light-Enhanced Glucose/Air Biofuel Cells.

    PubMed

    Wu, Kaiqing; Zhang, Yan; Wang, Yanhu; Ge, Shenguang; Yan, Mei; Yu, Jinghua; Song, Xianrang

    2015-11-01

    A strategy that combines visible-light-enhanced biofuel cells (BFCs) and electrochemical immunosensor into paper-based analytical devices was proposed for sensitive detection of the carbohydrate antigen 15-3 (CA15-3). The gold nanoparticle modified paper electrode with large surface area and good conductibility was applied as an effective matrix for primary antibodies. The glucose dehydrogenase (GDH) modified gold-silver bimetallic nanoparticles were used as bioanodic biocatalyst and signal magnification label. Poly(terthiophene) (pTTh), a photoresponsive conducting polymer, served as catalyst in cathode for the reduction of oxygen upon illumination by visible light. In the bioanode, electrons were generated through the oxidation of glucose catalyzed by GDH. The amount of electrons is determined by the amount of GDH, which finally depended on the amount of CA15-3. In the cathode, electrons from the bioanode could combine with the generated holes in the HOMO energy level of cathode catalysts pTTh. Meanwhile, the high energy level photoexcited electrons were generated in the LUMO energy level and involved in the oxygen reduction reaction, finally resulting in an increasing current and a decreasing overpotential. According to the current signal, simple and efficient detection of CA15-3 was achieved.

  1. Maintaining thermogenesis in cold exposed humans: relying on multiple metabolic pathways.

    PubMed

    Blondin, Denis P; Tingelstad, Hans Christian; Mantha, Olivier L; Gosselin, Chantal; Haman, François

    2014-10-01

    In cold exposed humans, increasing thermogenic rate is essential to prevent decreases in core temperature. This review describes the metabolic requirements of thermogenic pathways, mainly shivering thermogenesis, the largest contributor of heat. Research has shown that thermogenesis is sustained from a combination of carbohydrates, lipids, and proteins. The mixture of fuels is influenced by shivering intensity and pattern as well as by modifications in energy reserves and nutritional status. To date, there are no indications that differences in the types of fuel being used can alter shivering and overall heat production. We also bring forth the potential contribution of nonshivering thermogenesis in adult humans via the activation of brown adipose tissue (BAT) and explore some means to stimulate the activity of this highly thermogenic tissue. Clearly, the potential role of BAT, especially in young lean adults, can no longer be ignored. However, much work remains to clearly identify the quantitative nature of this tissue's contribution to total thermogenic rate and influence on shivering thermogenesis. Identifying ways to potentiate the effects of BAT via cold acclimation and/or the ingestion of compounds that stimulate the thermogenic process may have important implications in cold endurance and survival. PMID:25428848

  2. Evolution of a thienopyrimidine antitubercular relying on medicinal chemistry and metabolomics insights#

    PubMed Central

    Li, Shao-Gang; Vilchèze, Catherine; Chakraborty, Sumit; Wang, Xin; Kim, Hiyun; Anisetti, Monica; Ekins, Sean; Rhee, Kyu Y.; Jacobs, William R.; Freundlich, Joel S.

    2015-01-01

    The metabolic instability of an antitubercular small molecule CD117 was addressed through iterative alteration of a key sulfide substituent and interrogation of the effect on growth inhibition of cultured Mycobacterium tuberculosis. This process was informed by studies of the intramycobacterial metabolism of CD117 and its inactive carboxylic acid derivative. Isoxazole 4e and thiazole 4m demonstrated significant gains in mouse liver microsomal stability with slight losses in whole-cell activity. This work illustrates the challenges of antitubercular hit evolution, requiring a balance of chemical and biological insights. PMID:26257441

  3. Desiccation tolerance in the tardigrade Richtersius coronifer relies on muscle mediated structural reorganization.

    PubMed

    Halberg, Kenneth Agerlin; Jørgensen, Aslak; Møbjerg, Nadja

    2013-01-01

    Life unfolds within a framework of constraining abiotic factors, yet some organisms are adapted to handle large fluctuations in physical and chemical parameters. Tardigrades are microscopic ecdysozoans well known for their ability to endure hostile conditions, such as complete desiccation--a phenomenon called anhydrobiosis. During dehydration, anhydrobiotic animals undergo a series of anatomical changes. Whether this reorganization is an essential regulated event mediated by active controlled processes, or merely a passive result of the dehydration process, has not been clearly determined. Here, we investigate parameters pivotal to the formation of the so-called "tun", a state that in tardigrades and rotifers marks the entrance into anhydrobiosis. Estimation of body volume in the eutardigrade Richtersius coronifer reveals an 87 % reduction in volume from the hydrated active state to the dehydrated tun state, underlining the structural stress associated with entering anhydrobiosis. Survival experiments with pharmacological inhibitors of mitochondrial energy production and muscle contractions show that i) mitochondrial energy production is a prerequisite for surviving desiccation, ii) uncoupling the mitochondria abolishes tun formation, and iii) inhibiting the musculature impairs the ability to form viable tuns. We moreover provide a comparative analysis of the structural changes involved in tun formation, using a combination of cytochemistry, confocal laser scanning microscopy and 3D reconstructions as well as scanning electron microscopy. Our data reveal that the musculature mediates a structural reorganization vital for anhydrobiotic survival, and furthermore that maintaining structural integrity is essential for resumption of life following rehydration. PMID:24391987

  4. Response to “Accurate Risk-Based Chemical Screening Relies on Robust Exposure Estimates”

    EPA Science Inventory

    This is a correspondence (letter to the editor) with reference to comments by Rudel and Perovich on the article "Integration of Dosimetry, Exposure, and High-Throughput Screening Data in Chemical Toxicity Assessment". Article Reference: SI # 238882

  5. Optical Frequency Measurements Relying on a Mid-Infrared Frequency Standard

    NASA Astrophysics Data System (ADS)

    Rovera, G. Daniele; Acef, Ouali

    Only a small number of groups are capable of measuring optical frequencies throughout the world. In this contribution we present some of the underlying philosophy of such frequency measurement systems, including some important theoretical hints. In particular, we concentrate on the approach that has been used with the BNM-LPTF frequency chain, where a separate secondary frequency standard in the mid-infrared has been used. The low-frequency section of the chain is characterized by a measurement of the phase noise spectral density Sφ at 716GHz.Most of the significant measurements performed in the last decade are briefly presented, together with a report on the actual stability and reproducibility of the CO2/ OsO4 frequency standard.Measuring the frequency of an optical frequency standard by direct comparison with the signal available at the output of a primary frequency standard (usually between 5MHz and 100MHz) requires a multiplication factor greater than 107. A number of possible configurations, using harmonic generation, sum or difference frequency generation, have been proposed and realized in the past [1,2,3,4,5,6] and in more recent times [7]. A new technique, employing a femtosecond laser, is presently giving its first impressive results [8].All of the classical frequency chains require a large amount of manpower, together with a great deal of simultaneously operating hardware. This has the consequence that only a very few systems are actually in an operating condition throughout the world.

  6. Severely obese adolescent girls rely earlier on carbohydrates during walking than normal-weight matched girls.

    PubMed

    Gavarry, Olivier; Aguer, Celine; Delextrat, Anne; Lentin, Gregory; Ayme, Karine; Boussuges, Alain

    2015-01-01

    The purpose of this study was to determine the substrate oxidation rate and the exercise intensity at which maximal lipid oxidation and ventilatory threshold (VT) occur in obese (BMI: 36.6 ± 6.3 kg · m(-2)) and normal-weight adolescent girls (BMI: 18.7 ± 1.6 kg · m(-2)) aged 14-18 years. Substrate oxidation rate was determined by gas exchange using an incremental field test involving walking. Body composition was assessed by bioelectrical impedance. Carbohydrate oxidation rates were significantly higher in obese than in normal-weight girls at speeds ranging from 4 to 6 km · h(-1) (P < 0.05), whereas no significant differences were observed between groups regarding lipid oxidation rates. The crossover point of substrate utilisation and the VT were significantly lower in obese than in normal-weight adolescents (P < 0.05). Maximal lipid oxidation rate was observed at 46 ± 15 and 53 ± 15 %EVO2max in obese and normal-weight adolescents, respectively. At these intensities, the Lipox(max) was significantly lower in obese than in normal-weight girls (6.7 ± 2.3 versus 8.9 ± 3.5 mg · min(-1) · kg(-1) FFM, P < 0.05, 95% CI: -3.7 to -0.7, d = -0.74). The present results have implications in designing interventions to promote lipid oxidation and energy expenditure during walking in severely obese adolescent girls.

  7. Eiger-induced cell death relies on Rac1-dependent endocytosis.

    PubMed

    Ruan, W; Srinivasan, A; Lin, S; Kara, k-I; Barker, P A

    2016-01-01

    Signaling via tumor necrosis factor receptor (TNFR) superfamily members regulates cellular life and death decisions. A subset of mammalian TNFR proteins, most notably the p75 neurotrophin receptor (p75NTR), induces cell death through a pathway that requires activation of c-Jun N-terminal kinases (JNKs). However the receptor-proximal signaling events that mediate this remain unclear. Drosophila express a single tumor necrosis factor (TNF) ligand termed Eiger (Egr) that activates JNK-dependent cell death. We have exploited this model to identify phylogenetically conserved signaling events that allow Egr to induce JNK activation and cell death in vivo. Here we report that Rac1, a small GTPase, is specifically required in Egr-mediated cell death. rac1 loss of function blocks Egr-induced cell death, whereas Rac1 overexpression enhances Egr-induced killing. We identify Vav as a GEF for Rac1 in this pathway and demonstrate that dLRRK functions as a negative regulator of Rac1 that normally acts to constrain Egr-induced death. Thus dLRRK loss of function increases Egr-induced cell death in the fly. We further show that Rac1-dependent entry of Egr into early endosomes is a crucial prerequisite for JNK activation and for cell death and show that this entry requires the activity of Rab21 and Rab7. These findings reveal novel regulatory mechanisms that allow Rac1 to contribute to Egr-induced JNK activation and cell death. PMID:27054336

  8. Chunking Improves Symbolic Sequence Processing and Relies on Working Memory Gating Mechanisms

    ERIC Educational Resources Information Center

    Solopchuk, Oleg; Alamia, Andrea; Olivier, Etienne; Zénon, Alexandre

    2016-01-01

    Chunking, namely the grouping of sequence elements in clusters, is ubiquitous during sequence processing, but its impact on performance remains debated. Here, we found that participants who adopted a consistent chunking strategy during symbolic sequence learning showed a greater improvement of their performance and a larger decrease in cognitive…

  9. Evolutionary differences in food preference rely on Gr64e, a receptor for glycerol.

    PubMed

    Wisotsky, Zev; Medina, Adriana; Freeman, Erica; Dahanukar, Anupama

    2011-12-01

    Very little is known about how stimuli that are typically not rich in sugars, such as beer, trigger attractive gustatory responses in Drosophila. We identified a member of the gustatory receptor family, Gr64e, as a receptor that is required for feeding preference for beer and other sources that have fermenting yeast. We found that Gr64e is required for neuronal and behavioral responses to glycerol, an abundant component of growing yeast and fermentation products. Ectopic expression of Gr64e in an olfactory neuron conferred responsiveness to glycerol. We also found that Drosophila species that are predicted to carry pseudogenes of Gr64e had reduced glycerol sensitivity. Our results provide insight into the molecular mechanisms of feeding acceptance of yeast products and raise the possibility that Gr64e contributes to specific evolutionary variations in appetitive selectivity across Drosophila species.

  10. Spider orb webs rely on radial threads to absorb prey kinetic energy

    PubMed Central

    Sensenig, Andrew T.; Lorentz, Kimberly A.; Kelly, Sean P.; Blackledge, Todd A.

    2012-01-01

    The kinetic energy of flying insect prey is a formidable challenge for orb-weaving spiders. These spiders construct two-dimensional, round webs from a combination of stiff, strong radial silk and highly elastic, glue-coated capture spirals. Orb webs must first stop the flight of insect prey and then retain those insects long enough to be subdued by the spiders. Consequently, spider silks rank among the toughest known biomaterials. The large number of silk threads composing a web suggests that aerodynamic dissipation may also play an important role in stopping prey. Here, we quantify energy dissipation in orb webs spun by diverse species of spiders using data derived from high-speed videos of web deformation under prey impact. By integrating video data with material testing of silks, we compare the relative contributions of radial silk, the capture spiral and aerodynamic dissipation. Radial silk dominated energy absorption in all webs, with the potential to account for approximately 100 per cent of the work of stopping prey in larger webs. The most generous estimates for the roles of capture spirals and aerodynamic dissipation show that they rarely contribute more than 30 per cent and 10 per cent of the total work of stopping prey, respectively, and then only for smaller orb webs. The reliance of spider orb webs upon internal energy absorption by radial threads for prey capture suggests that the material properties of the capture spirals are largely unconstrained by the selective pressures of stopping prey and can instead evolve freely in response to alternative functional constraints such as adhering to prey. PMID:22431738

  11. Pathogenicity of Salmonella enterica in Caenorhabditis elegans relies on disseminated oxidative stress in the infected host.

    PubMed

    Sem, XiaoHui; Rhen, Mikael

    2012-01-01

    Feeding Caenorhabditis elegans with Salmonella enterica serovar Typhimurium significantly shortens the lifespan of the nematode. S. Typhimurium-infected C. elegans, stained with 2',7'-dichlorodihydrofluorescein diacetate which fluoresces upon exposure to reactive oxygen species, revealed intestinal luminal staining that along with the time of infection progressed to a strong staining in the hypodermal tissues of the nematode. Still, we could not detect invasion beyond the nematode's intestinal epithelium at any stage of the infection. A similar dispersion of oxidative response was also noted in nematodes infected with S. Dublin, but not with non-pathogenic Escherichia coli or the defined pathogen Burkholderia thailandensis. Addition of catalase or the reductant ascorbic acid significantly restored the lifespan of S. Typhimurium-infected nematodes. Mutational inactivation of the bacterial thioredoxin 1 resulted in total ablation of the hypodermal oxidative response to infection, and in a strong attenuation of virulence. Virulence of the thioredoxin 1 mutant was restored by trans-complementation with redox-active variants of thioredoxin 1 or, surprisingly, by exposing the thioredoxin 1 mutant to sublethal concentrations of the disulphide catalyst copper chloride prior to infection. In summary, our observations define a new aspect in virulence of S. enterica that apparently does not involve the classical invasive or intracellular phenotype of the pathogen, but that depends on the ability to provoke overwhelming systemic oxidative stress in the host through the redox activity of bacterial thioredoxin 1. PMID:23028994

  12. Relying on High-Stakes Standardized Tests to Evaluate Schools and Teachers: A Bad Idea

    ERIC Educational Resources Information Center

    Morgan, Hani

    2016-01-01

    In the twenty-first century, the use of standardized tests as the primary means to evaluate schools and teachers in the United States has contributed to severe dilemmas, including misleading information on what students know, lower-level instruction, cheating, less collaboration, unfair treatment of teachers, and biased teaching. This article…

  13. Heterogeneity in European research integrity guidance: relying on values or norms?

    PubMed

    Godecharle, Simon; Nemery, Benoit; Dierickx, Kris

    2014-07-01

    Similar forms of misconduct are perceived differently throughout Europe. There are no extensive surveys on the guidance on research integrity in the different countries of Europe. Therefore, we performed a systematic content analysis of (biomedical) research integrity guidance documents from all the countries of the European Economic Area. We show that there is strong heterogeneity concerning research integrity guidance on crucial aspects, for example, the defining of research misconduct, at both an international and a national level. We also sought to explain why the guidance documents differ by distinguishing the approaches that underlie them. We distinguished a value-based and a norm-based approach, as well as different perspectives on trust. The current confusing situation concerning research integrity guidance hampers international research and possibly wastes research funds. We risk talking past each other, if we do not take the distinction between these underlying approaches into account.

  14. When to rely on maternal effects and when on phenotypic plasticity?

    PubMed Central

    Kuijper, Bram; Hoyle, Rebecca B.

    2015-01-01

    Existing insight suggests that maternal effects have a substantial impact on evolution, yet these predictions assume that maternal effects themselves are evolutionarily constant. Hence, it is poorly understood how natural selection shapes maternal effects in different ecological circumstances. To overcome this, the current study derives an evolutionary model of maternal effects in a quantitative genetics context. In constant environments, we show that maternal effects evolve to slight negative values that result in a reduction of the phenotypic variance (canalization). By contrast, in populations experiencing abrupt change, maternal effects transiently evolve to positive values for many generations, facilitating the transmission of beneficial maternal phenotypes to offspring. In periodically fluctuating environments, maternal effects evolve according to the autocorrelation between maternal and offspring environments, favoring positive maternal effects when change is slow, and negative maternal effects when change is rapid. Generally, the strongest maternal effects occur for traits that experience very strong selection and for which plasticity is severely constrained. By contrast, for traits experiencing weak selection, phenotypic plasticity enhances the evolutionary scope of maternal effects, although maternal effects attain much smaller values throughout. As weak selection is common, finding substantial maternal influences on offspring phenotypes may be more challenging than anticipated. PMID:25809121

  15. Neuronal growth cone retraction relies upon proneurotrophin receptor signaling through Rac

    PubMed Central

    Deinhardt, Katrin; Kim, Taeho; Spellman, Daniel S.; Mains, Richard E.; Eipper, Betty A.; Neubert, Thomas A.; Chao, Moses V.; Hempstead, Barbara L.

    2012-01-01

    Growth of axons and dendrites is a dynamic process that involves guidance molecules, adhesion proteins, and neurotrophic factors. Although neurite extension during development has been extensively studied, the intracellular mechanisms that mediate neurite retraction are poorly understood. Here, we show that the proneurotrophin, proNGF, induces acute collapse of growth cones of cultured hippocampal neurons. This retraction is initiated by an interaction between p75NTR and the sortilin family member, SorCS2 (sortilin-related VPS10 domain containing receptor 2). Binding of proNGF to the p75NTR-SorCS2 complex induced growth cone retraction by initiating the dissociation of the guanine-nucleotide exchange factor Trio from the p75NTR- SorCS2 complex, resulting in decreased Rac activity, and consequently, growth cone collapse. The actin-bundling protein fascin also became inactivated, contributing to the destabilization and collapse of actin filaments. These results identify a bifunctional signaling mechanism by which proNGF regulates actin dynamics to modulate neuronal morphology acutely. PMID:22155786

  16. Regulators and regulations: who will guard the guards? (or 'Quis custodiet ipsos custodes' as old Juvenal used to say).

    PubMed

    Kelleher, Martin

    2015-06-01

    Overbearing regulators with their various labyrinthine regulations have had adverse impacts on dentists and their teams' behaviours. This has produced the perverse outcomes of demoralizing dental teams as well as reducing their capacity and/or desire to deliver compassionate oral healthcare. These adverse outcomes do not seem to have benefited patients, or dentists, or their teams, in any sensible or measurable way. CPD/CLINICAL RELEVANCE: The vastly increased burdens on the UK dental profession of intrusive, bullying regulations, emanating from the various UK agencies, such as the supposedly fair and independent GDC, but including the increasingly politically controlled NHS and the CQC, have had unfortunate, perverse, effects on many dentists' clinical practices and affected dental teams' desires, or willingness, to be as compassionate as they used to be about helping to solve some patients' dental or oral problems. PMID:26964442

  17. Et pourquoi pas une education aux sciences qui aborde la participation des acteurs sociaux aux controverses sociotechniques?

    ERIC Educational Resources Information Center

    Pouliot, Chantal

    2012-01-01

    In this article we discuss research that was conducted as part of a project on citizen science education. We present the research and some of the results, and then take a position on the pertinence of examining, in science classes, questions on citizen participation in socio-technical debates and the roles and capacities of the social actors…

  18. 78 FR 3911 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-17

    ... for the next 15 years. ADDRESSES: You will find the final CCP, a summary of the final CCP, and the EA... managers with a 15-year strategy for achieving refuge purposes and contributing toward the mission of the... Federal Register (73 FR 76677) on December 17, 2008. For more about the initial process and the history...

  19. QUIS: Queen's University Information Systems; Report of Activities for the Period Ending on 31st December, 1972.

    ERIC Educational Resources Information Center

    Queen's Univ., Belfast (Northern Ireland). Dept. of Computer Science.

    Two computer information systems, one for reference retrieval and the other for the retrieval of numerical data on atomic and molecular physics are being developed at the Queen's University of Belfast. The reference retrieval system is based on the atomic and molecular physics section of the INSPEC tapes. The tapes contain complete abstracts of…

  20. The Behavior-Physiology Nexus: Behavioral and Physiological Compensation Are Relied on to Different Extents between Seasons.

    PubMed

    Basson, Christine H; Clusella-Trullas, Susana

    2015-01-01

    Environmental variability occurring at different timescales can significantly reduce performance, resulting in evolutionary fitness costs. Shifts in thermoregulatory behavior, metabolism, and water loss via phenotypic plasticity can compensate for thermal variation, but the relative contribution of each mechanism and how they may influence each other are largely unknown. Here, we take an ecologically relevant experimental approach to dissect these potential responses at two temporal scales: weather transients and seasons. Using acclimation to cold, average, or warm conditions in summer and winter, we measure the direction and magnitude of plasticity of resting metabolic rate (RMR), water loss rate (WLR), and preferred body temperature (Tpref) in the lizard Cordylus oelofseni within and between seasons. In summer, lizards selected lower Tpref when acclimated to warm versus cold but had no plasticity of either RMR or WLR. By contrast, winter lizards showed partial compensation of RMR but no behavioral compensation. Between seasons, both behavioral and physiological shifts took place. By integrating ecological reality into laboratory assays, we demonstrate that behavioral and physiological responses of C. oelofseni can be contrasting, depending on the timescale investigated. Incorporating ecologically relevant scenarios and the plasticity of multiple traits is thus essential when attempting to forecast extinction risk to climate change.

  1. Dorsoventral polarity of the Nasonia embryo primarily relies on a BMP gradient formed without input from Toll.

    PubMed

    Özüak, Orhan; Buchta, Thomas; Roth, Siegfried; Lynch, Jeremy A

    2014-10-20

    In Drosophila, Toll signaling leads to a gradient of nuclear uptake of Dorsal with a peak at the ventral egg pole and is the source for dorsoventral (DV) patterning and polarity of the embryo. In contrast, Toll signaling plays no role in embryonic patterning in most animals, while BMP signaling plays the major role. In order to understand the origin of the novelty of the Drosophila system, we have examined DV patterning in Nasonia vitripennis (Nv), a representative of the Hymenoptera and thus the most ancient branch points within the Holometabola. We have previously shown that while the expression of several conserved DV patterning genes is almost identical in Nasonia and Drosophila embryos at the onset of gastrulation, the ways these patterns evolve in early embryogenesis are very different from what is seen in Drosophila or the beetle Tribolium. In contrast to Drosophila or Tribolium, we find that wasp Toll has a very limited ventral role, whereas BMP is required for almost all DV polarity of the embryo, and these two signaling systems act independently of each other to generate DV polarity. This result gives insights into how the Toll pathway could have usurped a BMP-based DV patterning system in insects. In addition, our work strongly suggests that a novel system for BMP activity gradient formation must be employed in the wasp, since orthologs of crucial components of the fly system are either missing entirely or lack function in the embryo.

  2. Paper-based biosensor relying on flower-like reduced graphene guided enzymatically deposition of polyaniline for Pb(2+) detection.

    PubMed

    Ge, Shenguang; Wu, Kaiqing; Zhang, Yan; Yan, Mei; Yu, Jinghua

    2016-06-15

    A multi-amplified paper-based electrochemical strategy using Pb(2+) dependent DNAzyme as the recognition unit for Pb(2+) detection was developed. In this work, flower-like reduced graphene (FrGO) was prepared utilizing flower-like ZnO as template, which was first one step grown on the gold nanoparticles modified paper working electrode (Au-PWE). After being treated with acid and then modified with Au, a novel sensor platform named Au/FrGO/Au-PWE with large specific surface area and good electrical conductivity was fabricated. The Mn2O3 nanoparticle-assembled hierarchical hollow spheres (H-Mn2O3) was served as nanocarrier to immobilize GOx, HRP and signal strand (S3), resulting to the formation of S3/H-Mn2O3/HRP/GOx bioconjugations. In the presence of Pb(2+), the DNAzyme (S1) was activated and the substrate strand (S2) was cleaved. After the incubation with S3/H-Mn2O3/HRP/GOx in 0.1M HAc-NaAc solution (pH 4.3) containing 30 mM aniline and 15 mM glucose, a readily measurable "turn-on" electrochemical signal could be measured. On the basis of the signal amplification strategy of Au/FrGO/Au-PWE sensing platform and S3/H-Mn2O3/HRP/GOx bioconjugations, the developed biosensor exhibited a good linear response toward over a wide range of concentration from 0.005 to 2000 nM. PMID:26851578

  3. Tor1, Sch9 and PKA downregulation in quiescence rely on Mtl1 to preserve mitochondrial integrity and cell survival.

    PubMed

    Sundaram, Venkatraghavan; Petkova, Mima I; Pujol-Carrion, Nuria; Boada, Jordi; de la Torre-Ruiz, Maria Angeles

    2015-07-01

    Here we show that Mtl1, member of the cell wall integrity pathway of Saccharomyces cerevisiae, plays a positive role in chronological life span (CLS). The absence of Mtl1 shortens CLS and causes impairment in the mitochondrial function. This is reflected in a descent in oxygen consumption during the postdiauxic state, an increase in the uncoupled respiration and mitochondrial membrane potential and also a descent in aconitase activity. We demonstrate that all these effects are a consequence of signalling defects suppressed by TOR1 (target of rapamycin) and SCH9 deletion and less efficiently by Protein kinase A (PKA) inactivation. Mtl1 also plays a role in the regulation of both Bcy1 stability and phosphorylation, mainly in response to glucose depletion. In postdiauxic phase and in conditions of glucose depletion, Mtl1 negatively regulates TOR1 function leading to Sch9 inactivation and Bcy1 phosphorylation converging in PKA inhibition. Slt2/Mpk1 kinase partially contributes to Bcy1 phosphorylation, although additional targets are not excluded. Mtl1 links mitochondrial dysfunction with TOR and PKA pathways in quiescence, glucose being the main signalling molecule.

  4. Thiol-Based Peroxidases and Ascorbate Peroxidases: Why Plants Rely on Multiple Peroxidase Systems in the Photosynthesizing Chloroplast?

    PubMed

    Dietz, Karl-Josef

    2016-01-01

    Photosynthesis is a highly robust process allowing for rapid adjustment to changing environmental conditions. The efficient acclimation depends on balanced redox metabolism and control of reactive oxygen species release which triggers signaling cascades and potentially detrimental oxidation reactions. Thiol peroxidases of the peroxiredoxin and glutathione peroxidase type, and ascorbate peroxidases are the main peroxide detoxifying enzymes of the chloroplast. They use different electron donors and are linked to distinct redox networks. In addition, the peroxiredoxins serve functions in redox regulation and retrograde signaling. The complexity of plastid peroxidases is discussed in context of suborganellar localization, substrate preference, metabolic coupling, protein abundance, activity regulation, interactions, signaling functions, and the conditional requirement for high antioxidant capacity. Thus the review provides an opinion on the advantage of linking detoxification of peroxides to different enzymatic systems and implementing mechanisms for their inactivation to enforce signal propagation within and from the chloroplast.

  5. Immigrant and Refugee Students across "Receiving" Nations: To What Extent Can Educators Rely on PISA for Answers?

    ERIC Educational Resources Information Center

    Rubinstein-Avila, Eliane

    2016-01-01

    Massive population shift is a current global reality--especially given some of the latest development on European shores; some are calling it a humanitarian crisis. Although the United States (US) receives a large number of immigrants (documented and not) and about 70,000 refugees each year, it is certainly not the only nation to do so.…

  6. Therapeutic Targeting of the Warburg Effect in Pancreatic Cancer Relies on an Absence of p53 Function.

    PubMed

    Rajeshkumar, N V; Dutta, Prasanta; Yabuuchi, Shinichi; de Wilde, Roeland F; Martinez, Gary V; Le, Anne; Kamphorst, Jurre J; Rabinowitz, Joshua D; Jain, Sanjay K; Hidalgo, Manuel; Dang, Chi V; Gillies, Robert J; Maitra, Anirban

    2015-08-15

    The "Warburg effect" describes a peculiar metabolic feature of many solid tumors, namely their increased glucose uptake and high glycolytic rates, which allow cancer cells to accumulate building blocks for the biosynthesis of macromolecules. During aerobic glycolysis, pyruvate is preferentially metabolized to lactate by the enzyme lactate dehydrogenase-A (LDH-A), suggesting a possible vulnerability at this target for small-molecule inhibition in cancer cells. In this study, we used FX11, a small-molecule inhibitor of LDH-A, to investigate this possible vulnerability in a panel of 15 patient-derived mouse xenograft (PDX) models of pancreatic cancer. Unexpectedly, the p53 status of the PDX tumor determined the response to FX11. Tumors harboring wild-type (WT) TP53 were resistant to FX11. In contrast, tumors harboring mutant TP53 exhibited increased apoptosis, reduced proliferation indices, and attenuated tumor growth when exposed to FX11. [18F]-FDG PET-CT scans revealed a relative increase in glucose uptake in mutant TP53 versus WT TP53 tumors, with FX11 administration downregulating metabolic activity only in mutant TP53 tumors. Through a noninvasive quantitative assessment of lactate production, as determined by 13C magnetic resonance spectroscopy (MRS) of hyperpolarized pyruvate, we confirmed that FX11 administration inhibited pyruvate-to-lactate conversion only in mutant TP53 tumors, a feature associated with reduced expression of the TP53 target gene TIGAR, which is known to regulate glycolysis. Taken together, our findings highlight p53 status in pancreatic cancer as a biomarker to predict sensitivity to LDH-A inhibition, with regard to both real-time noninvasive imaging by 13C MRS as well as therapeutic response. PMID:26113084

  7. The Behavior-Physiology Nexus: Behavioral and Physiological Compensation Are Relied on to Different Extents between Seasons.

    PubMed

    Basson, Christine H; Clusella-Trullas, Susana

    2015-01-01

    Environmental variability occurring at different timescales can significantly reduce performance, resulting in evolutionary fitness costs. Shifts in thermoregulatory behavior, metabolism, and water loss via phenotypic plasticity can compensate for thermal variation, but the relative contribution of each mechanism and how they may influence each other are largely unknown. Here, we take an ecologically relevant experimental approach to dissect these potential responses at two temporal scales: weather transients and seasons. Using acclimation to cold, average, or warm conditions in summer and winter, we measure the direction and magnitude of plasticity of resting metabolic rate (RMR), water loss rate (WLR), and preferred body temperature (Tpref) in the lizard Cordylus oelofseni within and between seasons. In summer, lizards selected lower Tpref when acclimated to warm versus cold but had no plasticity of either RMR or WLR. By contrast, winter lizards showed partial compensation of RMR but no behavioral compensation. Between seasons, both behavioral and physiological shifts took place. By integrating ecological reality into laboratory assays, we demonstrate that behavioral and physiological responses of C. oelofseni can be contrasting, depending on the timescale investigated. Incorporating ecologically relevant scenarios and the plasticity of multiple traits is thus essential when attempting to forecast extinction risk to climate change. PMID:26052635

  8. The Relative Effectiveness of Signaling Systems: Relying on External Items Reduces Signaling Accuracy while Leks Increase Accuracy

    PubMed Central

    Leighton, Gavin M.

    2014-01-01

    Multiple evolutionary phenomena require individual animals to assess conspecifics based on behaviors, morphology, or both. Both behavior and morphology can provide information about individuals and are often used as signals to convey information about quality, motivation, or energetic output. In certain cases, conspecific receivers of this information must rank these signaling individuals based on specific traits. The efficacy of information transfer associated within a signal is likely related to the type of trait used to signal, though few studies have investigated the relative effectiveness of contrasting signaling systems. I present a set of models that represent a large portion of signaling systems and compare them in terms of the ability of receivers to rank signalers accurately. Receivers more accurately assess signalers if the signalers use traits that do not require non-food resources; similarly, receivers more accurately ranked signalers if all the signalers could be observed simultaneously, similar to leks. Surprisingly, I also found that receivers are only slightly better at ranking signaler effort if the effort results in a cumulative structure. This series of findings suggests that receivers may attend to specific traits because the traits provide more information relative to others; and similarly, these results may explain the preponderance of morphological and behavioral display signals. PMID:24626221

  9. Do Political and Economic Choices Rely on Common Neural Substrates? A Systematic Review of the Emerging Neuropolitics Literature.

    PubMed

    Krastev, Sekoul; McGuire, Joseph T; McNeney, Denver; Kable, Joseph W; Stolle, Dietlind; Gidengil, Elisabeth; Fellows, Lesley K

    2016-01-01

    The methods of cognitive neuroscience are beginning to be applied to the study of political behavior. The neural substrates of value-based decision-making have been extensively examined in economic contexts; this might provide a powerful starting point for understanding political decision-making. Here, we asked to what extent the neuropolitics literature to date has used conceptual frameworks and experimental designs that make contact with the reward-related approaches that have dominated decision neuroscience. We then asked whether the studies of political behavior that can be considered in this light implicate the brain regions that have been associated with subjective value related to "economic" reward. We performed a systematic literature review to identify papers addressing the neural substrates of political behavior and extracted the fMRI studies reporting behavioral measures of subjective value as defined in decision neuroscience studies of reward. A minority of neuropolitics studies met these criteria and relatively few brain activation foci from these studies overlapped with regions where activity has been related to subjective value. These findings show modest influence of reward-focused decision neuroscience on neuropolitics research to date. Whether the neural substrates of subjective value identified in economic choice paradigms generalize to political choice thus remains an open question. We argue that systematically addressing the commonalities and differences in these two classes of value-based choice will be important in developing a more comprehensive model of the brain basis of human decision-making. PMID:26941703

  10. A CORF computational model of a simple cell that relies on LGN input outperforms the Gabor function model.

    PubMed

    Azzopardi, George; Petkov, Nicolai

    2012-03-01

    Simple cells in primary visual cortex are believed to extract local contour information from a visual scene. The 2D Gabor function (GF) model has gained particular popularity as a computational model of a simple cell. However, it short-cuts the LGN, it cannot reproduce a number of properties of real simple cells, and its effectiveness in contour detection tasks has never been compared with the effectiveness of alternative models. We propose a computational model that uses as afferent inputs the responses of model LGN cells with center-surround receptive fields (RFs) and we refer to it as a Combination of Receptive Fields (CORF) model. We use shifted gratings as test stimuli and simulated reverse correlation to explore the nature of the proposed model. We study its behavior regarding the effect of contrast on its response and orientation bandwidth as well as the effect of an orthogonal mask on the response to an optimally oriented stimulus. We also evaluate and compare the performances of the CORF and GF models regarding contour detection, using two public data sets of images of natural scenes with associated contour ground truths. The RF map of the proposed CORF model, determined with simulated reverse correlation, can be divided in elongated excitatory and inhibitory regions typical of simple cells. The modulated response to shifted gratings that this model shows is also characteristic of a simple cell. Furthermore, the CORF model exhibits cross orientation suppression, contrast invariant orientation tuning and response saturation. These properties are observed in real simple cells, but are not possessed by the GF model. The proposed CORF model outperforms the GF model in contour detection with high statistical confidence (RuG data set: p<10(-4), and Berkeley data set: p<10(-4)). The proposed CORF model is more realistic than the GF model and is more effective in contour detection, which is assumed to be the primary biological role of simple cells. PMID:22526357

  11. Cadmium-induced ethylene production and responses in Arabidopsis thaliana rely on ACS2 and ACS6 gene expression

    PubMed Central

    2014-01-01

    Background Anthropogenic activities cause metal pollution worldwide. Plants can absorb and accumulate these metals through their root system, inducing stress as a result of excess metal concentrations inside the plant. Ethylene is a regulator of multiple plant processes, and is affected by many biotic and abiotic stresses. Increased ethylene levels have been observed after exposure to excess metals but it remains unclear how the increased ethylene levels are achieved at the molecular level. In this study, the effects of cadmium (Cd) exposure on the production of ethylene and its precursor 1-aminocyclopropane-1-carboxylic acid (ACC), and on the expression of the ACC Synthase (ACS) and ACC Oxidase (ACO) multigene families were investigated in Arabidopsis thaliana. Results Increased ethylene release after Cd exposure was directly measurable in a system using rockwool-cultivated plants; enhanced levels of the ethylene precursor ACC together with higher mRNA levels of ethylene responsive genes: ACO2, ETR2 and ERF1 also indicated increased ethylene production in hydroponic culture. Regarding underlying mechanisms, it was found that the transcript levels of ACO2 and ACO4, the most abundantly expressed members of the ACO multigene family, were increased upon Cd exposure. ACC synthesis is the rate-limiting step in ethylene biosynthesis, and transcript levels of both ACS2 and ACS6 showed the highest increase and became the most abundant isoforms after Cd exposure, suggesting their importance in the Cd-induced increase of ethylene production. Conclusions Cadmium induced the biosynthesis of ACC and ethylene in Arabidopsis thaliana plants mainly via the increased expression of ACS2 and ACS6. This was confirmed in the acs2-1acs6-1 double knockout mutants, which showed a decreased ethylene production, positively affecting leaf biomass and resulting in a delayed induction of ethylene responsive gene expressions without significant differences in Cd contents between wild-type and mutant plants. PMID:25082369

  12. Does Maintenance of Colour Categories Rely on Language? Evidence to the Contrary from a Case of Semantic Dementia

    ERIC Educational Resources Information Center

    Haslam, C.; Wills, A. J.; Haslam, S. A.; Kay, J.; Baron, R.; McNab, F.

    2007-01-01

    Recent neuropsychological evidence, supporting a strong version of Whorfian principles of linguistic relativity, has reinvigorated debate about the role of language in colour categorisation. This paper questions the methodology used in this research and uses a novel approach to examine the unique contribution of language to categorisation…

  13. The prosensory function of Sox2 in the chicken inner ear relies on the direct regulation of Atoh1.

    PubMed

    Neves, Joana; Uchikawa, Masanori; Bigas, Anna; Giraldez, Fernando

    2012-01-01

    The proneural gene Atoh1 is crucial for the development of inner ear hair cells and it requires the function of the transcription factor Sox2 through yet unknown mechanisms. In the present work, we used the chicken embryo and HEK293T cells to explore the regulation of Atoh1 by Sox2. The results show that hair cells derive from Sox2-positive otic progenitors and that Sox2 directly activates Atoh1 through a transcriptional activator function that requires the integrity of Sox2 DNA binding domain. Atoh1 activation depends on Sox transcription factor binding sites (SoxTFBS) present in the Atoh1 3' enhancer where Sox2 directly binds, as shown by site directed mutagenesis and chromatin immunoprecipitation (ChIP). In the inner ear, Atoh1 enhancer activity is detected in the neurosensory domain and it depends on Sox2. Dominant negative competition (Sox2HMG-Engrailed) and mutation of the SoxTFBS abolish the reporter activity in vivo. Moreover, ChIP assay in isolated otic vesicles shows that Sox2 is bound to the Atoh1 enhancer in vivo. However, besides activating Atoh1, Sox2 also promotes the expression of Atoh1 negative regulators and the temporal profile of Atoh1 activation by Sox2 is transient suggesting that Sox2 triggers an incoherent feed-forward loop. These results provide a mechanism for the prosensory function of Sox2 in the inner ear. We suggest that sensory competence is established early in otic development through the activation of Atoh1 by Sox2, however, hair cell differentiation is prevented until later stages by the parallel activation of negative regulators of Atoh1 function.

  14. D-cycloserine facilitation of fear extinction and exposure-based therapy might rely on lower-level, automatic mechanisms.

    PubMed

    Grillon, Christian

    2009-10-01

    Exposure-based therapy, a leading technique in the treatment of a range of anxiety disorders, is facilitated by D-cycloserine (DCS), a partial N-methyl-D-aspartate receptor agonist. This review discusses the potential mechanisms involved in this facilitation and its implications for developing theories of fear conditioning in humans. Basic research in rodents suggests that DCS acts by speeding up extinction. However, several laboratory-based investigations found that DCS had no effect on extinction in humans. This report proposes that these observations can be accounted for by a dual-model theory of fear conditioning in humans that engages two complementary defensive systems: a reflexive lower-order system independent of conscious awareness and a higher-order cognitive system associated with conscious awareness of danger and expectation. The DCS studies in animals seem to have explored lower-order conditioning mechanisms, whereas human studies have explored higher-order cognitive processes. These observations suggest that DCS might act preferentially on lower- rather than higher-order learning. This report presents evidence suggesting that, in humans, DCS might similarly affect lower-order learning during exposure-based therapy and, consequently, might be less effective during cognitive therapy (e.g., cognitive restructuring). Finally, it is recommended that extinction studies using DCS in humans be conducted with fear-relevant stimuli (e.g., snakes), short conditional stimulus-unconditioned stimulus intervals and intense unconditioned stimulus to promote lower-order conditioning processes.

  15. Development of a millimetrically scaled biodiesel transesterification device that relies on droplet-based co-axial fluidics.

    PubMed

    Yeh, S I; Huang, Y C; Cheng, C H; Cheng, C M; Yang, J T

    2016-01-01

    In this study, we investigated a fluidic system that adheres to new concepts of energy production. To improve efficiency, cost, and ease of manufacture, a millimetrically scaled device that employs a droplet-based co-axial fluidic system was devised to complete alkali-catalyzed transesterification for biodiesel production. The large surface-to-volume ratio of the droplet-based system, and the internal circulation induced inside the moving droplets, significantly enhanced the reaction rate of immiscible liquids used here - soybean oil and methanol. This device also decreased the molar ratio between methanol and oil to near the stoichiometric coefficients of a balanced chemical equation, which enhanced the total biodiesel volume produced, and decreased the costs of purification and recovery of excess methanol. In this work, the droplet-based co-axial fluidic system performed better than other methods of continuous-flow production. We achieved an efficiency that is much greater than that of reported systems. This study demonstrated the high potential of droplet-based fluidic chips for energy production. The small energy consumption and low cost of the highly purified biodiesel transesterification system described conforms to the requirements of distributed energy (inexpensive production on a moderate scale) in the world. PMID:27426677

  16. Enterocyte loss of polarity and gut wound healing rely upon the F-actin-severing function of villin.

    PubMed

    Ubelmann, Florent; Chamaillard, Mathias; El-Marjou, Fatima; Simon, Anthony; Netter, Jeanne; Vignjevic, Danijela; Nichols, Buford L; Quezada-Calvillo, Roberto; Grandjean, Teddy; Louvard, Daniel; Revenu, Céline; Robine, Sylvie

    2013-04-01

    Efficient wound healing is required to maintain the integrity of the intestinal epithelial barrier because of its constant exposure to a large variety of environmental stresses. This process implies a partial cell depolarization and the acquisition of a motile phenotype that involves rearrangements of the actin cytoskeleton. Here we address how polarized enterocytes harboring actin-rich apical microvilli undergo extensive cell remodeling to drive injury repair. Using live imaging technologies, we demonstrate that enterocytes in vitro and in vivo rapidly depolarize their microvilli at the wound edge. Through its F-actin-severing activity, the microvillar actin-binding protein villin drives both apical microvilli disassembly in vitro and in vivo and promotes lamellipodial extension. Photoactivation experiments indicate that microvillar actin is mobilized at the lamellipodium, allowing optimal migration. Finally, efficient repair of colonic mechanical injuries requires villin severing of F-actin, emphasizing the importance of villin function in intestinal homeostasis. Thus, villin severs F-actin to ensure microvillus depolarization and enterocyte remodeling upon injury. This work highlights the importance of specialized apical pole disassembly for the repolarization of epithelial cells initiating migration.

  17. Concerted removal of the Erb1–Ytm1 complex in ribosome biogenesis relies on an elaborate interface

    PubMed Central

    Thoms, Matthias; Ahmed, Yasar Luqman; Maddi, Karthik; Hurt, Ed; Sinning, Irmgard

    2016-01-01

    The complicated process of eukaryotic ribosome biogenesis involves about 200 assembly factors that transiently associate with the nascent pre-ribosome in a spatiotemporally ordered way. During the early steps of 60S subunit formation, several proteins, collectively called A3 cluster factors, participate in the removal of the internal transcribed spacer 1 (ITS1) from 27SA3 pre-rRNA. Among these factors is the conserved hetero-trimeric Nop7–Erb1–Ytm1 complex (or human Pes1–Bop1–Wdr12), which is removed from the evolving pre-60S particle by the AAA ATPase Rea1 to allow progression in the pathway. Here, we clarify how Ytm1 and Erb1 interact, which has implications for the release mechanism of both factors from the pre-ribosome. Biochemical studies show that Ytm1 and Erb1 bind each other via their ß-propeller domains. The crystal structure of the Erb1–Ytm1 heterodimer determined at 2.67Å resolution reveals an extended interaction surface between the propellers in a rarely observed binding mode. Structure-based mutations in the interface that impair the Erb1–Ytm1 interaction do not support growth, with specific defects in 60S subunit synthesis. Under these mutant conditions, it becomes clear that an intact Erb1–Ytm1 complex is required for 60S maturation and that loss of this stable interaction prevents ribosome production. PMID:26657628

  18. If the results of an article are noteworthy, read the entire article; do not rely on the abstract alone.

    PubMed

    Dal-Ré, R; Castell, M V; García-Puig, J

    2015-11-01

    Clinicians typically update their knowledge by reading articles on the Internet. Easy access to the articles' abstracts and a lack of time to access other information sources creates a risk that therapeutic or diagnostic decisions will be made after reading just the abstracts. Occasionally, however, the abstracts of articles from clinical trials that have not obtained statistically significant differences in the primary study endpoint have reported other positive results, for example, of a secondary endpoint or a subgroup analysis. The article, however, correctly reports all results, including those of the primary endpoint. In the abstract, the safety information of the experimental treatment is usually deficient. The whole article should be read if a clinical decision is to be made. PMID:26165166

  19. Spinopelvic pathways to bipedality: why no hominids ever relied on a bent-hip-bent-knee gait.

    PubMed

    Lovejoy, C Owen; McCollum, Melanie A

    2010-10-27

    Until recently, the last common ancestor of African apes and humans was presumed to resemble living chimpanzees and bonobos. This was frequently extended to their locomotor pattern leading to the presumption that knuckle-walking was a likely ancestral pattern, requiring bipedality to have emerged as a modification of their bent-hip-bent-knee gait used during erect walking. Research on the development and anatomy of the vertebral column, coupled with new revelations from the fossil record (in particular, Ardipithecus ramidus), now demonstrate that these presumptions have been in error. Reassessment of the potential pathway to early hominid bipedality now reveals an entirely novel sequence of likely morphological events leading to the emergence of upright walking.

  20. Yeast Tolerance to Various Stresses Relies on the Trehalose-6P Synthase (Tps1) Protein, Not on Trehalose*

    PubMed Central

    Petitjean, Marjorie; Teste, Marie-Ange; François, Jean M.; Parrou, Jean-Luc

    2015-01-01

    Trehalose is a stable disaccharide commonly found in nature, from bacteria to fungi and plants. For the model yeast Saccharomyces cerevisiae, claims that trehalose is a stress protectant were based indirectly either on correlation between accumulation of trehalose and high resistance to various stresses or on stress hypersensitivity of mutants deleted for TPS1, which encodes the first enzyme in trehalose biosynthetic pathway. Our goal was to investigate more directly which one, between trehalose and/or the Tps1 protein, may serve yeast cells to withstand exposure to stress. By employing an original strategy that combined the use of mutant strains expressing catalytically inactive variants of Tps1, with MAL+ yeast strains able to accumulate trehalose from an exogenous supply, we bring for the first time unbiased proof that trehalose does not protect yeast cells from dying and that the stress-protecting role of trehalose in this eukaryotic model was largely overestimated. Conversely, we identified the Tps1 protein as a key player for yeast survival in response to temperature, oxidative, and desiccation stress. We also showed by robust RT-quantitative PCR and genetic interaction analysis that the role of Tps1 in thermotolerance is not dependent upon Hsf1-dependent transcription activity. Finally, our results revealed that the Tps1 protein is essential to maintain ATP levels during heat shock. Altogether, these findings supported the idea that Tps1 is endowed with a regulatory function in energy homeostasis, which is essential to withstand adverse conditions and maintain cellular integrity. PMID:25934390

  1. Autoimmunity conferred by chs3-2D relies on CSA1, its adjacent TNL-encoding neighbour.

    PubMed

    Xu, Fang; Zhu, Chipan; Cevik, Volkan; Johnson, Kaeli; Liu, Yanan; Sohn, Kee; Jones, Jonathan D; Holub, Eric B; Li, Xin

    2015-03-05

    Plant innate immunity depends on the function of a large number of intracellular immune receptor proteins, the majority of which are structurally similar to mammalian nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) proteins. CHILLING SENSITIVE 3 (CHS3) encodes an atypical Toll/Interleukin 1 Receptor (TIR)-type NLR protein with an additional Lin-11, Isl-1 and Mec-3 (LIM) domain at its C-terminus. The gain-of-function mutant allele chs3-2D exhibits severe dwarfism and constitutively activated defense responses, including enhanced resistance to virulent pathogens, high defence marker gene expression, and salicylic acid accumulation. To search for novel regulators involved in CHS3-mediated immune signaling, we conducted suppressor screens in the chs3-2D and chs3-2D pad4-1 genetic backgrounds. Alleles of sag101 and eds1-90 were isolated as complete suppressors of chs3-2D, and alleles of sgt1b were isolated as partial suppressors of chs3-2D pad4-1. These mutants suggest that SAG101, EDS1-90, and SGT1b are all positive regulators of CHS3-mediated defense signaling. Additionally, the TIR-type NLR-encoding CSA1 locus located genomically adjacent to CHS3 was found to be fully required for chs3-2D-mediated autoimmunity. CSA1 is located 3.9 kb upstream of CHS3 and is transcribed in the opposite direction. Altogether, these data illustrate the distinct genetic requirements for CHS3-mediated defense signaling.

  2. Do adults with cochlear implants rely on different acoustic cues for phoneme perception than adults with normal hearing?

    PubMed Central

    Moberly, Aaron C.; Lowenstein, Joanna H.; Tarr, Eric; Caldwell-Tarr, Amanda; Welling, D. Bradley; Shahin, Antoine J.; Nittrouer, Susan

    2014-01-01

    Purpose Several acoustic cues specify any single phonemic contrast. Nonetheless, adult, native speakers of a language share weighting strategies, showing preferential attention to some properties over others. Cochlear implant (CI) signal processing disrupts the salience of some cues: in general, amplitude structure remains readily available, but spectral structure less so. This study asked how well speech recognition is supported if CI users shift attention to salient cues not weighted strongly by native speakers. Method 20 adults with CIs participated. The /bɑ/-/wɑ/ contrast was used because spectral and amplitude structure varies in correlated fashion for this contrast. Normal-hearing adults weight the spectral cue strongly, but the amplitude cue negligibly. Three measurements were made: labeling decisions, spectral and amplitude discrimination, and word recognition. Results Outcomes varied across listeners: some weighted the spectral cue strongly, some weighted the amplitude cue, and some weighted neither. Spectral discrimination predicted spectral weighting. Spectral weighting explained the most variance in word recognition. Age of onset of hearing loss predicted spectral weighting, but not unique variance in word recognition. Conclusions The weighting strategies of listeners with normal hearing likely support speech recognition best, so efforts in implant design, fitting, and training should focus on developing those strategies. PMID:24686722

  3. Inhibitory motor control based on complex stopping goals relies on the same brain network as simple stopping.

    PubMed

    Wessel, Jan R; Aron, Adam R

    2014-12-01

    Much research has modeled action-stopping using the stop-signal task (SST), in which an impending response has to be stopped when an explicit stop-signal occurs. A limitation of the SST is that real-world action-stopping rarely involves explicit stop-signals. Instead, the stopping-system engages when environmental features match more complex stopping goals. For example, when stepping into the street, one monitors path, velocity, size, and types of objects and only stops if there is a vehicle approaching. Here, we developed a task in which participants compared the visual features of a multidimensional go-stimulus to a complex stopping-template, and stopped their go-response if all features matched the template. We used independent component analysis of EEG data to show that the same motor inhibition brain network that explains action-stopping in the SST also implements motor inhibition in the complex-stopping task. Furthermore, we found that partial feature overlap between go-stimulus and stopping-template led to motor slowing, which also corresponded with greater stopping-network activity. This shows that the same brain system for action-stopping to explicit stop-signals is recruited to slow or stop behavior when stimuli match a complex stopping goal. The results imply a generalizability of the brain's network for simple action-stopping to more ecologically valid scenarios.

  4. Concerted removal of the Erb1-Ytm1 complex in ribosome biogenesis relies on an elaborate interface.

    PubMed

    Thoms, Matthias; Ahmed, Yasar Luqman; Maddi, Karthik; Hurt, Ed; Sinning, Irmgard

    2016-01-29

    The complicated process of eukaryotic ribosome biogenesis involves about 200 assembly factors that transiently associate with the nascent pre-ribosome in a spatiotemporally ordered way. During the early steps of 60S subunit formation, several proteins, collectively called A3 cluster factors, participate in the removal of the internal transcribed spacer 1 (ITS1) from 27SA3 pre-rRNA. Among these factors is the conserved hetero-trimeric Nop7-Erb1-Ytm1 complex (or human Pes1-Bop1-Wdr12), which is removed from the evolving pre-60S particle by the AAA ATPase Rea1 to allow progression in the pathway. Here, we clarify how Ytm1 and Erb1 interact, which has implications for the release mechanism of both factors from the pre-ribosome. Biochemical studies show that Ytm1 and Erb1 bind each other via their ß-propeller domains. The crystal structure of the Erb1-Ytm1 heterodimer determined at 2.67Å resolution reveals an extended interaction surface between the propellers in a rarely observed binding mode. Structure-based mutations in the interface that impair the Erb1-Ytm1 interaction do not support growth, with specific defects in 60S subunit synthesis. Under these mutant conditions, it becomes clear that an intact Erb1-Ytm1 complex is required for 60S maturation and that loss of this stable interaction prevents ribosome production. PMID:26657628

  5. So you want to work? What employers say about job skills, recruitment and hiring employees who rely on AAC.

    PubMed

    Bryen, Diane Nelson; Potts, Blyden B; Carey, Allison C

    2007-06-01

    In order to better understand employer perspectives with respect to hiring and working with people who use AAC and the kinds of employment barriers they believe exist for these individuals, a study into the job requirements, recruitment processes, and hiring processes of 27 employers in the United States was conducted. Interviews with the 27 employers focused on 48 jobs in 25 unique categories, many of which had previously been identified as desirable by 38 adults who used AAC (some of whom were employed and some of whom were seeking employment). Findings suggest that, while level of education is still important to employers, skills such as time management, problem solving, communication, use of an understandable and standard voice, and basic technology may be even more so. The study also found that having an effective job-related network is important, as is the ability to provide credible references and do well during in-person interviews with potential employers.

  6. Development of a millimetrically scaled biodiesel transesterification device that relies on droplet-based co-axial fluidics

    PubMed Central

    Yeh, S. I.; Huang, Y. C.; Cheng, C. H.; Cheng, C. M.; Yang, J. T.

    2016-01-01

    In this study, we investigated a fluidic system that adheres to new concepts of energy production. To improve efficiency, cost, and ease of manufacture, a millimetrically scaled device that employs a droplet-based co-axial fluidic system was devised to complete alkali-catalyzed transesterification for biodiesel production. The large surface-to-volume ratio of the droplet-based system, and the internal circulation induced inside the moving droplets, significantly enhanced the reaction rate of immiscible liquids used here – soybean oil and methanol. This device also decreased the molar ratio between methanol and oil to near the stoichiometric coefficients of a balanced chemical equation, which enhanced the total biodiesel volume produced, and decreased the costs of purification and recovery of excess methanol. In this work, the droplet-based co-axial fluidic system performed better than other methods of continuous-flow production. We achieved an efficiency that is much greater than that of reported systems. This study demonstrated the high potential of droplet-based fluidic chips for energy production. The small energy consumption and low cost of the highly purified biodiesel transesterification system described conforms to the requirements of distributed energy (inexpensive production on a moderate scale) in the world. PMID:27426677

  7. D-cycloserine facilitation of fear extinction and exposure-based therapy might rely on lower-level, automatic mechanisms.

    PubMed

    Grillon, Christian

    2009-10-01

    Exposure-based therapy, a leading technique in the treatment of a range of anxiety disorders, is facilitated by D-cycloserine (DCS), a partial N-methyl-D-aspartate receptor agonist. This review discusses the potential mechanisms involved in this facilitation and its implications for developing theories of fear conditioning in humans. Basic research in rodents suggests that DCS acts by speeding up extinction. However, several laboratory-based investigations found that DCS had no effect on extinction in humans. This report proposes that these observations can be accounted for by a dual-model theory of fear conditioning in humans that engages two complementary defensive systems: a reflexive lower-order system independent of conscious awareness and a higher-order cognitive system associated with conscious awareness of danger and expectation. The DCS studies in animals seem to have explored lower-order conditioning mechanisms, whereas human studies have explored higher-order cognitive processes. These observations suggest that DCS might act preferentially on lower- rather than higher-order learning. This report presents evidence suggesting that, in humans, DCS might similarly affect lower-order learning during exposure-based therapy and, consequently, might be less effective during cognitive therapy (e.g., cognitive restructuring). Finally, it is recommended that extinction studies using DCS in humans be conducted with fear-relevant stimuli (e.g., snakes), short conditional stimulus-unconditioned stimulus intervals and intense unconditioned stimulus to promote lower-order conditioning processes. PMID:19520359

  8. The antibacterial activity of a microwave argon plasma jet at atmospheric pressure relies mainly on UV-C radiations

    NASA Astrophysics Data System (ADS)

    Judée, F.; Wattieaux, G.; Merbahi, N.; Mansour, M.; Castanié-Cornet, M. P.

    2014-10-01

    The main bactericidal sources produced by a microwave induced cold argon plasma jet in open air are identified and their relative proportion in the biocide efficiency of the jet is assessed on planktonic Gram-negative bacteria (wild-type strains and deletion mutants of Escherichia coli) diluted in water. In these conditions ultraviolet light (UV) most probably in the UV-C region of the electromagnetic spectrum, is responsible for 86.7 ± 3.2% of the observed bactericidal efficiency of the jet whereas hydrogen peroxide represents 9.9 ± 5.5% of it. The exposition level of the bacteria to UV-C radiations is estimated at 20 mJ cm-2 using a specific photodiode and the influence of the initial bacteria concentration on the apparent antibacterial efficiency of the jet is highlighted.

  9. The Prosensory Function of Sox2 in the Chicken Inner Ear Relies on the Direct Regulation of Atoh1

    PubMed Central

    Neves, Joana; Uchikawa, Masanori; Bigas, Anna; Giraldez, Fernando

    2012-01-01

    The proneural gene Atoh1 is crucial for the development of inner ear hair cells and it requires the function of the transcription factor Sox2 through yet unknown mechanisms. In the present work, we used the chicken embryo and HEK293T cells to explore the regulation of Atoh1 by Sox2. The results show that hair cells derive from Sox2-positive otic progenitors and that Sox2 directly activates Atoh1 through a transcriptional activator function that requires the integrity of Sox2 DNA binding domain. Atoh1 activation depends on Sox transcription factor binding sites (SoxTFBS) present in the Atoh1 3′ enhancer where Sox2 directly binds, as shown by site directed mutagenesis and chromatin immunoprecipitation (ChIP). In the inner ear, Atoh1 enhancer activity is detected in the neurosensory domain and it depends on Sox2. Dominant negative competition (Sox2HMG-Engrailed) and mutation of the SoxTFBS abolish the reporter activity in vivo. Moreover, ChIP assay in isolated otic vesicles shows that Sox2 is bound to the Atoh1 enhancer in vivo. However, besides activating Atoh1, Sox2 also promotes the expression of Atoh1 negative regulators and the temporal profile of Atoh1 activation by Sox2 is transient suggesting that Sox2 triggers an incoherent feed-forward loop. These results provide a mechanism for the prosensory function of Sox2 in the inner ear. We suggest that sensory competence is established early in otic development through the activation of Atoh1 by Sox2, however, hair cell differentiation is prevented until later stages by the parallel activation of negative regulators of Atoh1 function. PMID:22292066

  10. The Plasma Membrane Calcium Pump in Pancreatic Cancer Cells Exhibiting the Warburg Effect Relies on Glycolytic ATP*

    PubMed Central

    James, Andrew D.; Patel, Waseema; Butt, Zohra; Adiamah, Magretta; Dakhel, Raga; Latif, Ayse; Uggenti, Carolina; Swanton, Eileithyia; Imamura, Hiromi; Siriwardena, Ajith K.; Bruce, Jason I. E.

    2015-01-01

    Evidence suggests that the plasma membrane Ca2+-ATPase (PMCA), which is critical for maintaining a low intracellular Ca2+ concentration ([Ca2+]i), utilizes glycolytically derived ATP in pancreatic ductal adenocarcinoma (PDAC) and that inhibition of glycolysis in PDAC cell lines results in ATP depletion, PMCA inhibition, and an irreversible [Ca2+]i overload. We explored whether this is a specific weakness of highly glycolytic PDAC by shifting PDAC cell (MIA PaCa-2 and PANC-1) metabolism from a highly glycolytic phenotype toward mitochondrial metabolism and assessing the effects of mitochondrial versus glycolytic inhibitors on ATP depletion, PMCA inhibition, and [Ca2+]i overload. The highly glycolytic phenotype of these cells was first reversed by depriving MIA PaCa-2 and PANC-1 cells of glucose and supplementing with α-ketoisocaproate or galactose. These culture conditions resulted in a significant decrease in both glycolytic flux and proliferation rate, and conferred resistance to ATP depletion by glycolytic inhibition while sensitizing cells to mitochondrial inhibition. Moreover, in direct contrast to cells exhibiting a high glycolytic rate, glycolytic inhibition had no effect on PMCA activity and resting [Ca2+]i in α-ketoisocaproate- and galactose-cultured cells, suggesting that the glycolytic dependence of the PMCA is a specific vulnerability of PDAC cells exhibiting the Warburg phenotype. PMID:26294767

  11. Critical appraisal of quantitative PCR results in colorectal cancer research: can we rely on published qPCR results?

    PubMed

    Dijkstra, J R; van Kempen, L C; Nagtegaal, I D; Bustin, S A

    2014-06-01

    The use of real-time quantitative polymerase chain reaction (qPCR) in cancer research has become ubiquitous. The relative simplicity of qPCR experiments, which deliver fast and cost-effective results, means that each year an increasing number of papers utilizing this technique are being published. But how reliable are the published results? Since the validity of gene expression data is greatly dependent on appropriate normalisation to compensate for sample-to-sample and run-to-run variation, we have evaluated the adequacy of normalisation procedures in qPCR-based experiments. Consequently, we assessed all colorectal cancer publications that made use of qPCR from 2006 until August 2013 for the number of reference genes used and whether they had been validated. Using even these minimal evaluation criteria, the validity of only three percent (6/179) of the publications can be adequately assessed. We describe common errors, and conclude that the current state of reporting on qPCR in colorectal cancer research is disquieting. Extrapolated to the study of cancer in general, it is clear that the majority of studies using qPCR cannot be reliably assessed and that at best, the results of these studies may or may not be valid and at worst, pervasive incorrect normalisation is resulting in the wholesale publication of incorrect conclusions. This survey demonstrates that the existence of guidelines, such as MIQE, is necessary but not sufficient to address this problem and suggests that the scientific community should examine its responsibility and be aware of the implications of these findings for current and future research.

  12. Therapeutic targeting of the Warburg effect in pancreatic cancer relies on an absence of p53 function

    PubMed Central

    Rajeshkumar, N.V.; Dutta, Prasanta; Yabuuchi, Shinichi; de Wilde, Roeland F.; Matrinez, Gary V.; Le, Anne; Kamphorst, Jurre J.; Rabinowitz, Josh D.; Jain, Sanjay K.; Hidalgo, Manuel; Dang, Chi V.; Gillies, Robert J.; Maitra, Anirban

    2015-01-01

    The “Warburg effect” describes a peculiar metabolic feature of many solid tumors, namely their high glycolytic activity for biosynthesis and an inefficient generation of ATP. During aerobic glycolysis, pyruvate is preferentially metabolized to lactate by the enzyme lactate dehydrogenase-A (LDH-A), suggesting a possible vulnerability at this target for small molecule inhibition in cancer cells. In this study, we used FX11, a small molecule inhibitor of LDH-A, to investigate this possible vulnerability in a panel of 15 patient-derived mouse xenograft (PDX) models of pancreatic cancer. Unexpectedly, the p53 status of the PDX tumor determined the response to FX11. Tumors harboring wild-type (WT) TP53 were completely resistant to FX11. In contrast, tumors harboring mutant TP53 exhibited increased apoptosis, reduced proliferation indices and attenuated tumor growth when exposed to FX11. [18F]-FDG PET-CT scans revealed a relative increase in glucose uptake in mutant TP53 versus WT TP53 tumors, with FX11 administration downregulating metabolic activity only in mutant TP53 tumors. Through a non-invasive quantitative assessment of lactate production, as determined by 13C magnetic resonance spectroscopy (MRS) of hyperpolarized pyruvate, we confirmed that FX11 administration inhibited pyruvate-to-lactate conversion only in mutant TP53 tumors, a feature associated with reduced expression of the TP53 target gene TIGAR, which is known to regulate glycolysis. Taken together, our findings highlight p53 status in pancreatic cancer as biomarker to predict sensitivity to LDH-A inhibition, with regard to both real-time non-invasive imaging by 13C MRS as well as therapeutic response. PMID:26113084

  13. Attending to multiple objects relies on both feature- and dimension-based control mechanisms: Evidence from human electrophysiology.

    PubMed

    Töllner, Thomas; Conci, Markus; Müller, Hermann J; Mazza, Veronica

    2016-10-01

    Numerous everyday search tasks require humans to attentionally select and temporally store more than one object present in the visual environment. Recently, several enumeration studies sought to isolate the mechanisms underlying multiple object processing by means of electrophysiological measures, which led to a more fine-grained picture as to which processing stages are modulated by object numerosity. One critical limitation that most of these studies share is that they used stimulus designs in which multiple targets were exclusively defined by the same feature value. Accordingly, it remains an open issue whether these findings generalize to search scenarios in which multiple targets are physically not identical. To systematically address this issue, we introduced three target context conditions in which multiple targets were defined randomly by (1) the same feature (sF), (2) different features within the same dimension (dFsD), or (3) different features across dimensions (dD). Our findings revealed that participants' ability to enumerate multiple targets was remarkably influenced by inter-target relationships, with fastest responses for sF trials, slowest responses for dD trials, and responses of intermediate speed for dFsD trials. Our electrophysiological analyses disclosed that one source of this response slowing was feature-based and originated from the stage of attentional selection (as indexed by PCN waves), whereas another source was dimension-based and associated with working memory processes (as indexed by P3b waves). Overall, our results point to a significant role of physical inter-target relationships in multiple object processing-a factor that has been largely neglected in most studies on enumeration.

  14. Lactoperoxidase folding and catalysis relies on the stabilization of the alpha-helix rich core domain: a thermal unfolding study.

    PubMed

    Boscolo, Barbara; Leal, Sónia S; Ghibaudi, Elena M; Gomes, Cláudio M

    2007-09-01

    Lactoperoxidase (LPO) belongs to the mammalian peroxidase family and catalyzes the oxidation of halides, pseudo-halides and a number of aromatic substrates at the expense of hydrogen peroxide. Despite the complex physiological role of LPO and its potential involvement in carcinogenic mechanisms, cystic fibrosis and inflammatory processes, little is known on the folding and structural stability of this protein. We have undertaken an investigation of the conformational dynamics and catalytic properties of LPO during thermal unfolding, using complementary biophysical techniques (differential scanning calorimetry, electron spin resonance, optical absorption, fluorescence and circular dichroism spectroscopies) together with biological activity assays. LPO is a particularly stable protein, capable of maintaining catalysis and structural integrity up to a high temperature, undergoing irreversible unfolding at 70 degrees C. We have observed that the first stages of the thermal denaturation involve a minor conformational change occurring at 40 degrees C, possibly at the level of the protein beta-sheets, which nevertheless does not result in an unfolding transition. Only at higher temperature, the protein hydrophobic core, which is rich in alpha-helices, unfolds with concomitant disruption of the catalytic heme pocket and activity loss. Evidences concerning the stabilizing role of the disulfide bridges and the covalently bound heme cofactor are shown and discussed in the context of understanding the structural stability determinants in a relatively large protein.

  15. Redox balance mechanisms in Schistosoma mansoni rely on peroxiredoxins and albumin and implicate peroxiredoxins as novel drug targets.

    PubMed

    Sayed, Ahmed A; Cook, Shawna K; Williams, David L

    2006-06-23

    Schistosoma mansoni, a causative agent of schistosomiasis, resides in the hepatic portal circulation of their human host up to 30 years without being eliminated by the host immune attack. Production of an antioxidant "firewall," which would neutralize the oxidative assault generated by host immune defenses, is one proposed survival mechanism of the parasite. Schistosomes lack catalase, the main H2O2-neutralizing enzyme of many organisms, and their glutathione peroxidases are in the phospholipid class with poor reactivity toward H2O2. Evidence implicates peroxiredoxins (Prx) as providing the main enzymatic activity to reduce H2O2 in the parasite. Quantitative monitoring of Prx mRNAs during parasite life cycle indicated that Prx proteins are differentially expressed, with highest expression occurring in adult stages (oxidative resistant stages). Incubation of schistosomula with Prx1 double-stranded RNA knocked down total Prx enzymatic activity and resulted in lowered survival of cultured parasites compared with controls demonstrating that Prx are essential parasite proteins. These results represent the first report of lethal gene silencing in Schistosoma. Investigation of downstream effects of Prx silencing revealed an abrupt increase of lipid peroxides and the generation of several oxidized proteins. Using mass spectrometry, parasite albumin and actin were identified as the main oxidized proteins. Gene expression analysis showed that schistosome albumin was induced by oxidative stress. This study highlights Prx proteins as essential parasite proteins and potential new targets for anti-schistosome drug development and albumin as a novel, sacrificial oxidant scavenging protein in parasite redox regulation. PMID:16606626

  16. Do open-cycle hatcheries relying on tourism conserve sea turtles? Sri Lankan developments and economic-ecological considerations.

    PubMed

    Tisdell, Clem; Wilson, Clevo

    2005-04-01

    By combining economic analysis of markets with ecological parameters, this article considers the role that tourism-based sea turtle hatcheries (of an open-cycle type) can play in conserving populations of sea turtles. Background is provided on the nature and development of such hatcheries in Sri Lanka. The modeling facilitates the assessment of the impacts of turtle hatcheries on the conservation of sea turtles and enables the economic and ecological consequences of tourism, based on such hatcheries, to be better appreciated. The results demonstrate that sea turtle hatcheries serving tourists can make a positive contribution to sea turtle conservation, but that their conservation effectiveness depends on the way they are managed. Possible negative effects are also identified. Economic market models are combined with turtle population survival relationships to predict the conservation impact of turtle hatcheries and their consequence for the total economic value obtained from sea turtle populations.

  17. Multiple source genes of HAmo SINE actively expanded and ongoing retroposition in cyprinid genomes relying on its partner LINE

    PubMed Central

    2010-01-01

    Background We recently characterized HAmo SINE and its partner LINE in silver carp and bighead carp based on hybridization capture of repetitive elements from digested genomic DNA in solution using a bead-probe [1]. To reveal the distribution and evolutionary history of SINEs and LINEs in cyprinid genomes, we performed a multi-species search for HAmo SINE and its partner LINE using the bead-probe capture and internal-primer-SINE polymerase chain reaction (PCR) techniques. Results Sixty-seven full-size and 125 internal-SINE sequences (as well as 34 full-size and 9 internal sequences previously reported in bighead carp and silver carp) from 17 species of the family Cyprinidae were aligned as well as 14 new isolated HAmoL2 sequences. Four subfamilies (type I, II, III and IV), which were divided based on diagnostic nucleotides in the tRNA-unrelated region, expanded preferentially within a certain lineage or within the whole family of Cyprinidae as multiple active source genes. The copy numbers of HAmo SINEs were estimated to vary from 104 to 106 in cyprinid genomes by quantitative RT-PCR. Over one hundred type IV members were identified and characterized in the primitive cyprinid Danio rerio genome but only tens of sequences were found to be similar with type I, II and III since the type IV was the oldest subfamily and its members dispersed in almost all investigated cyprinid fishes. For determining the taxonomic distribution of HAmo SINE, inter-primer SINE PCR was conducted in other non-cyprinid fishes, the results shows that HAmo SINE- related sequences may disperse in other families of order Cypriniforms but absent in other orders of bony fishes: Siluriformes, Polypteriformes, Lepidosteiformes, Acipenseriformes and Osteoglossiforms. Conclusions Depending on HAmo LINE2, multiple source genes (subfamilies) of HAmo SINE actively expanded and underwent retroposition in a certain lineage or within the whole family of Cyprinidae. From this perspective, HAmo SINE should provide useful phylogenetic makers for future analyses of the evolutionary relationships among species in the family Cyprinidae. PMID:20426875

  18. Nocturnal Foraging by Red-Legged Kittiwakes, a Surface Feeding Seabird That Relies on Deep Water Prey During Reproduction

    PubMed Central

    Kokubun, Nobuo; Yamamoto, Takashi; Kikuchi, Dale M.; Kitaysky, Alexander; Takahashi, Akinori

    2015-01-01

    Narrow foraging specialization may increase the vulnerability of marine predators to climate change. The red-legged kittiwake (Rissa brevirostris) is endemic to the Bering Sea and has experienced drastic population fluctuations in recent decades, presumably due to climate-driven changes in food resources. Red-legged kittiwakes are presumed to be a nocturnal surface-foraging seabird that feed almost entirely on deep water Myctophidae fishes. However, there is little empirical evidence confirming their nocturnal foraging activity during the breeding season. This study investigated the foraging behavior of red-legged kittiwakes by combining GPS tracking, accelerometry, and dietary analyses at the world’s largest breeding colony of red-legged kittiwakes on St. George I. GPS tracking of 5 individuals revealed that 82.5% of non-flight behavior (including foraging and resting) occurred over the ocean basin (bottom depth >1,000 m). Acceleration data from 4 birds showed three types of behaviors during foraging trips: (1) flight, characterized by regular wing flapping, (2) resting on water, characterized by non-active behavior, and (3) foraging, when wing flapping was irregular. The proportions of both foraging and resting behaviors were higher at night (14.1 ± 7.1% and 20.8 ± 14.3%) compared to those during the day (6.5 ± 3.0% and 1.7 ± 2.7%). The mean duration of foraging (2.4 ± 2.9 min) was shorter than that of flight between prey patches (24.2 ± 53.1 min). Dietary analyses confirmed myctophids as the dominant prey (100% by occurrence and 98.4 ± 2.4% by wet-weight). Although the sample size was limited, these results suggest that breeding red-legged kittiwakes concentrated their foraging on myctophids available at the surface during nighttime in deep water regions. We propose that the diel patterns and ephemeral nature of their foraging activity reflected the availability of myctophids. Such foraging specialization may exacerbate the vulnerability of red-legged kittiwakes to climate change in the Bering Sea. PMID:26465335

  19. Catalytic ozonation of oxalate with a cerium supported palladium oxide: an efficient degradation not relying on hydroxyl radical oxidation.

    PubMed

    Zhang, Tao; Li, Weiwei; Croué, Jean-Philippe

    2011-11-01

    The cerium supported palladium oxide (PdO/CeO(2)) at a low palladium loading was found very effective in catalytic ozonation of oxalate, a probe compound that is difficult to be efficiently degraded in water with hydroxyl radical oxidation and one of the major byproducts in ozonation of organic matter. The oxalate was degraded into CO(2) during the catalytic ozonation. The molar ratio of oxalate degraded to ozone consumption increased with increasing catalyst dose and decreasing ozone dosage and pH under the conditions of this study. The maximum molar ratio reached around 1, meaning that the catalyst was highly active and selective for oxalate degradation in water. The catalytic ozonation, which showed relatively stable activity, does not promote hydroxyl radical generation from ozone. Analysis with ATR-FTIR and in situ Raman spectroscopy revealed that 1) oxalate was adsorbed on CeO(2) of the catalyst forming surface complexes, and 2) O(3) was adsorbed on PdO of the catalyst and further decomposed to surface atomic oxygen (*O), surface peroxide (*O(2)), and O(2) gas in sequence. The results indicate that the high activity of the catalyst is related to the synergetic function of PdO and CeO(2) in that the surface atomic oxygen readily reacts with the surface cerium-oxalate complex. This kind of catalytic ozonation would be potentially effective for the degradation of polar refractory organic pollutants and hydrophilic natural organic matter.

  20. The Importance of Relying on the Manual: Scoring Error Variance in the WISC-IV Vocabulary Subtest

    ERIC Educational Resources Information Center

    Erdodi, Laszlo A.; Richard, David C. S.; Hopwood, Christopher

    2009-01-01

    Classical test theory assumes that ability level has no effect on measurement error. Newer test theories, however, argue that the precision of a measurement instrument changes as a function of the examinee's true score. Research has shown that administration errors are common in the Wechsler scales and that subtests requiring subjective scoring…

  1. Position-dependent splicing activation and repression by SR and hnRNP proteins rely on common mechanisms

    PubMed Central

    Erkelenz, Steffen; Mueller, William F.; Evans, Melanie S.; Busch, Anke; Schöneweis, Katrin; Hertel, Klemens J.; Schaal, Heiner

    2013-01-01

    Alternative splicing is regulated by splicing factors that modulate splice site selection. In some cases, however, splicing factors show antagonistic activities by either activating or repressing splicing. Here, we show that these opposing outcomes are based on their binding location relative to regulated 5′ splice sites. SR proteins enhance splicing only when they are recruited to the exon. However, they interfere with splicing by simply relocating them to the opposite intronic side of the splice site. hnRNP splicing factors display analogous opposing activities, but in a reversed position dependence. Activation by SR or hnRNP proteins increases splice site recognition at the earliest steps of exon definition, whereas splicing repression promotes the assembly of nonproductive complexes that arrest spliceosome assembly prior to splice site pairing. Thus, SR and hnRNP splicing factors exploit similar mechanisms to positively or negatively influence splice site selection. PMID:23175589

  2. Adaptation of the symbiotic Mesorhizobium-chickpea relationship to phosphate deficiency relies on reprogramming of whole-plant metabolism.

    PubMed

    Nasr Esfahani, Maryam; Kusano, Miyako; Nguyen, Kien Huu; Watanabe, Yasuko; Ha, Chien Van; Saito, Kazuki; Sulieman, Saad; Herrera-Estrella, Luis; Tran, L S

    2016-08-01

    Low inorganic phosphate (Pi) availability is a major constraint for efficient nitrogen fixation in legumes, including chickpea. To elucidate the mechanisms involved in nodule acclimation to low Pi availability, two Mesorhizobium-chickpea associations exhibiting differential symbiotic performances, Mesorhizobium ciceri CP-31 (McCP-31)-chickpea and Mesorhizobium mediterranum SWRI9 (MmSWRI9)-chickpea, were comprehensively studied under both control and low Pi conditions. MmSWRI9-chickpea showed a lower symbiotic efficiency under low Pi availability than McCP-31-chickpea as evidenced by reduced growth parameters and down-regulation of nifD and nifK These differences can be attributed to decline in Pi level in MmSWRI9-induced nodules under low Pi stress, which coincided with up-regulation of several key Pi starvation-responsive genes, and accumulation of asparagine in nodules and the levels of identified amino acids in Pi-deficient leaves of MmSWRI9-inoculated plants exceeding the shoot nitrogen requirement during Pi starvation, indicative of nitrogen feedback inhibition. Conversely, Pi levels increased in nodules of Pi-stressed McCP-31-inoculated plants, because these plants evolved various metabolic and biochemical strategies to maintain nodular Pi homeostasis under Pi deficiency. These adaptations involve the activation of alternative pathways of carbon metabolism, enhanced production and exudation of organic acids from roots into the rhizosphere, and the ability to protect nodule metabolism against Pi deficiency-induced oxidative stress. Collectively, the adaptation of symbiotic efficiency under Pi deficiency resulted from highly coordinated processes with an extensive reprogramming of whole-plant metabolism. The findings of this study will enable us to design effective breeding and genetic engineering strategies to enhance symbiotic efficiency in legume crops. PMID:27450089

  3. Nocturnal Foraging by Red-Legged Kittiwakes, a Surface Feeding Seabird That Relies on Deep Water Prey During Reproduction.

    PubMed

    Kokubun, Nobuo; Yamamoto, Takashi; Kikuchi, Dale M; Kitaysky, Alexander; Takahashi, Akinori

    2015-01-01

    Narrow foraging specialization may increase the vulnerability of marine predators to climate change. The red-legged kittiwake (Rissa brevirostris) is endemic to the Bering Sea and has experienced drastic population fluctuations in recent decades, presumably due to climate-driven changes in food resources. Red-legged kittiwakes are presumed to be a nocturnal surface-foraging seabird that feed almost entirely on deep water Myctophidae fishes. However, there is little empirical evidence confirming their nocturnal foraging activity during the breeding season. This study investigated the foraging behavior of red-legged kittiwakes by combining GPS tracking, accelerometry, and dietary analyses at the world's largest breeding colony of red-legged kittiwakes on St. George I. GPS tracking of 5 individuals revealed that 82.5% of non-flight behavior (including foraging and resting) occurred over the ocean basin (bottom depth >1,000 m). Acceleration data from 4 birds showed three types of behaviors during foraging trips: (1) flight, characterized by regular wing flapping, (2) resting on water, characterized by non-active behavior, and (3) foraging, when wing flapping was irregular. The proportions of both foraging and resting behaviors were higher at night (14.1 ± 7.1% and 20.8 ± 14.3%) compared to those during the day (6.5 ± 3.0% and 1.7 ± 2.7%). The mean duration of foraging (2.4 ± 2.9 min) was shorter than that of flight between prey patches (24.2 ± 53.1 min). Dietary analyses confirmed myctophids as the dominant prey (100% by occurrence and 98.4 ± 2.4% by wet-weight). Although the sample size was limited, these results suggest that breeding red-legged kittiwakes concentrated their foraging on myctophids available at the surface during nighttime in deep water regions. We propose that the diel patterns and ephemeral nature of their foraging activity reflected the availability of myctophids. Such foraging specialization may exacerbate the vulnerability of red-legged kittiwakes to climate change in the Bering Sea.

  4. Effect of arbuscular mycorrhizal and bacterial inocula on nitrate concentration in mesocosms simulating a wastewater treatment system relying on phytodepuration.

    PubMed

    Lingua, Guido; Copetta, Andrea; Musso, Davide; Aimo, Stefania; Ranzenigo, Angelo; Buico, Alessandra; Gianotti, Valentina; Osella, Domenico; Berta, Graziella

    2015-12-01

    High nitrogen concentration in wastewaters requires treatments to prevent the risks of eutrophication in rivers, lakes and coastal waters. The use of constructed wetlands is one of the possible approaches to lower nitrate concentration in wastewaters. Beyond supporting the growth of the bacteria operating denitrification, plants can directly take up nitrogen. Since plant roots interact with a number of soil microorganisms, in the present work we report the monitoring of nitrate concentration in macrocosms with four different levels of added nitrate (0, 30, 60 and 90 mg l(-1)), using Phragmites australis, inoculated with bacteria or arbuscular mycorrhizal fungi, to assess whether the use of such inocula could improve wastewater denitrification. Higher potassium nitrate concentration increased plant growth and inoculation with arbuscular mycorrhizal fungi or bacteria resulted in larger plants with more developed root systems. In the case of plants inoculated with arbuscular mycorrhizal fungi, a faster decrease of nitrate concentration was observed, while the N%/C% ratio of the plants of the different treatments remained similar. At 90 mg l(-1) of added nitrate, only mycorrhizal plants were able to decrease nitrate concentration to the limits prescribed by the Italian law. These data suggest that mycorrhizal and microbial inoculation can be an additional tool to improve the efficiency of denitrification in the treatment of wastewaters via constructed wetlands.

  5. Leptin regulation of bone mass, appetite and energy expenditure relies on its ability to inhibit serotonin synthesis in the brainstem

    PubMed Central

    Yadav, Vijay K.; Oury, Franck; Suda, Nina; Liu, Zhong-Wu; Gao, Xiao-Bing; Confavreux, Cyrille; Klemenhagen, Kristen C; Tanaka, Kenji F.; Gingrich, Jay A.; Guo, X. Edward; Tecott, Laurence H.; Mann, J. John; Hen, Rene; Horvath, Tamas L.; Karsenty, Gerard

    2009-01-01

    Leptin inhibition of bone mass accrual requires the integrity of specific hypothalamic neurons but not expression of its receptor on these neurons. The same is true for its regulation of appetite and energy expenditure. This suggests that leptin acts elsewhere in the brain to achieve these three functions. We show here that brainstem-derived serotonin (BDS) favors bone mass accrual following its binding to Htr2c receptors on ventromedial hypothalamic neurons and appetite via Htr1a and 2b receptors on arcuate neurons. Leptin inhibits these functions and increases energy expenditure because it reduces serotonin synthesis and firing of serotonergic neurons. Accordingly, while abrogating BDS synthesis corrects the bone, appetite and energy expenditure phenotypes caused by leptin deficiency, inactivation of the leptin receptor in serotonergic neurons recapitulates them fully. This study modifies the map of leptin signaling in the brain and identifies a molecular basis for the common regulation of bone and energy metabolisms. PMID:19737523

  6. Do Political and Economic Choices Rely on Common Neural Substrates? A Systematic Review of the Emerging Neuropolitics Literature.

    PubMed

    Krastev, Sekoul; McGuire, Joseph T; McNeney, Denver; Kable, Joseph W; Stolle, Dietlind; Gidengil, Elisabeth; Fellows, Lesley K

    2016-01-01

    The methods of cognitive neuroscience are beginning to be applied to the study of political behavior. The neural substrates of value-based decision-making have been extensively examined in economic contexts; this might provide a powerful starting point for understanding political decision-making. Here, we asked to what extent the neuropolitics literature to date has used conceptual frameworks and experimental designs that make contact with the reward-related approaches that have dominated decision neuroscience. We then asked whether the studies of political behavior that can be considered in this light implicate the brain regions that have been associated with subjective value related to "economic" reward. We performed a systematic literature review to identify papers addressing the neural substrates of political behavior and extracted the fMRI studies reporting behavioral measures of subjective value as defined in decision neuroscience studies of reward. A minority of neuropolitics studies met these criteria and relatively few brain activation foci from these studies overlapped with regions where activity has been related to subjective value. These findings show modest influence of reward-focused decision neuroscience on neuropolitics research to date. Whether the neural substrates of subjective value identified in economic choice paradigms generalize to political choice thus remains an open question. We argue that systematically addressing the commonalities and differences in these two classes of value-based choice will be important in developing a more comprehensive model of the brain basis of human decision-making.

  7. 16 CFR 1115.5 - Reporting of failures to comply with a voluntary consumer product safety standard relied upon by...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... voluntary standard, or portion(s) thereof, is likely to result in an adequate reduction of the risk of... must report under this section if it has distributed in commerce, subsequent to the effective date of... or create an unreasonable risk of serious injury or death....

  8. PARKINSON'S DISEASE PATIENTS WITH DOMINANT HEMIBODY AFFECTED BY THE DISEASE RELY MORE ON VISION TO MAINTAIN UPRIGHT POSTURAL CONTROL.

    PubMed

    Lahr, Juliana; Pereira, Marcelo Pinto; Pelicioni, Paulo Henrique Silva; De Morais, Luana Carolina; Gobbi, Lilian Teresa Bucken

    2015-12-01

    This study assesses the association between disease onset side (dominant or non-dominant) and vision on postural control of Parkinson's disease patients. Patient volunteers composed two groups, according to the onset side affected: Dominant group (n=9; M age=66.1 yr., SD=7.2; 6 women, 3 men) and Non-dominant group (n=9; M age=67.4 yr., SD=6.4; 6 women, 3 men). The groups' postural control was assessed by posturography during quiet upright stance in two conditions, Eyes open and Eyes closed. Two-way analyses of variance (ANOVAs; group×condition) with repeated measures for the second factor assessed the differences associated with affected hemibody and vision on postural control. Analyses indicated that patients with the dominant side affected also presented significantly greater variation in center of pressure than those with the non-dominant side affected, mainly in the Eyes closed condition. The results demonstrate a higher reliance on vision in the dominant side, possibly to compensate somatosensory system impairments. These results also highlight the importance of analyzing the hemibody affected by the disease when postural control is assessed in this population.

  9. Proximal fibular stress fractures in children and adolescents, what should we rely on? Lessons learned from a case.

    PubMed

    de Pina, Carlos Aguiar Ramos; Balacó, Inês; Serrano, Pedro Ruas; Matos, Gabriel

    2015-02-16

    Fibula fractures are the third most common stress fractures in children and adolescents. The triad of localised periosteal reaction, endosteal thickening and radiolucent cortical lines, localised in the distal third of the fibula along with a typical clinical history is in most cases sufficient to establish the diagnosis. Proximal fibula stress lesions are a very rare finding, with few reports in the literature. Stress fractures in this location demand careful investigation before a definitive diagnosis can be made. In the presence of non-specific MRI findings, stress fracture should be a diagnosis of exclusion. The authors report a case referred to their department by a sports medicine physician with a suspicion of stress fracture of the proximal fibula without characteristic imaging findings, which was ultimately confirmed as a stress lesion only by biopsy.

  10. Self-control depletion in tufted capuchin monkeys (Sapajus spp.): does delay of gratification rely on a limited resource?

    PubMed Central

    Petrillo, Francesca De; Gori, Emanuele; Truppa, Valentina; Ariely, Dan; Addessi, Elsa

    2015-01-01

    Self-control failure has enormous personal and societal consequences. One of the most debated models explaining why self-control breaks down is the Strength Model, according to which self-control depends on a limited resource. Either previous acts of self-control or taking part in highly demanding cognitive tasks have been shown to reduce self-control, possibly due to a reduction in blood glucose levels. However, several studies yielded negative findings, and recent meta-analyses questioned the robustness of the depletion effect in humans. We investigated, for the first time, whether the Strength Model applies to a non-human primate species, the tufted capuchin monkey. We tested five capuchins in a self-control task (the Accumulation task) in which food items were accumulated within individual’s reach for as long as the subject refrained from taking them. We evaluated whether capuchins’ performance decreases: (i) when tested before receiving their daily meal rather than after consuming it (Energy Depletion Experiment), and (ii) after being tested in two tasks with different levels of cognitive complexity (Cognitive Depletion Experiment). We also tested, in both experiments, how implementing self-control in each trial of the Accumulation task affected this capacity within each session and/or across consecutive sessions. Repeated acts of self-control in each trial of the Accumulation task progressively reduced this capacity within each session, as predicted by the Strength Model. However, neither experiencing a reduction in energy level nor taking part in a highly demanding cognitive task decreased performance in the subsequent Accumulation task. Thus, whereas capuchins seem to be vulnerable to within-session depletion effects, to other extents our findings are in line with the growing body of studies that failed to find a depletion effect in humans. Methodological issues potentially affecting the lack of depletion effects in capuchins are discussed. PMID:26322001

  11. Adaptation of the symbiotic Mesorhizobium–chickpea relationship to phosphate deficiency relies on reprogramming of whole-plant metabolism

    PubMed Central

    Nasr Esfahani, Maryam; Kusano, Miyako; Nguyen, Kien Huu; Watanabe, Yasuko; Ha, Chien Van; Saito, Kazuki; Sulieman, Saad; Herrera-Estrella, Luis; Tran, Lam-Son Phan

    2016-01-01

    Low inorganic phosphate (Pi) availability is a major constraint for efficient nitrogen fixation in legumes, including chickpea. To elucidate the mechanisms involved in nodule acclimation to low Pi availability, two Mesorhizobium–chickpea associations exhibiting differential symbiotic performances, Mesorhizobium ciceri CP-31 (McCP-31)–chickpea and Mesorhizobium mediterranum SWRI9 (MmSWRI9)–chickpea, were comprehensively studied under both control and low Pi conditions. MmSWRI9–chickpea showed a lower symbiotic efficiency under low Pi availability than McCP-31–chickpea as evidenced by reduced growth parameters and down-regulation of nifD and nifK. These differences can be attributed to decline in Pi level in MmSWRI9-induced nodules under low Pi stress, which coincided with up-regulation of several key Pi starvation-responsive genes, and accumulation of asparagine in nodules and the levels of identified amino acids in Pi-deficient leaves of MmSWRI9-inoculated plants exceeding the shoot nitrogen requirement during Pi starvation, indicative of nitrogen feedback inhibition. Conversely, Pi levels increased in nodules of Pi-stressed McCP-31–inoculated plants, because these plants evolved various metabolic and biochemical strategies to maintain nodular Pi homeostasis under Pi deficiency. These adaptations involve the activation of alternative pathways of carbon metabolism, enhanced production and exudation of organic acids from roots into the rhizosphere, and the ability to protect nodule metabolism against Pi deficiency-induced oxidative stress. Collectively, the adaptation of symbiotic efficiency under Pi deficiency resulted from highly coordinated processes with an extensive reprogramming of whole-plant metabolism. The findings of this study will enable us to design effective breeding and genetic engineering strategies to enhance symbiotic efficiency in legume crops. PMID:27450089

  12. Enterocyte loss of polarity and gut wound healing rely upon the F-actin-severing function of villin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficient wound healing is required to maintain the integrity of the intestinal epithelial barrier because of its constant exposure to a large variety of environmental stresses. This process implies a partial cell depolarization and the acquisition of a motile phenotype that involves rearrangements ...

  13. Travelling light: white sharks (Carcharodon carcharias) rely on body lipid stores to power ocean-basin scale migration.

    PubMed

    Del Raye, Gen; Jorgensen, Salvador J; Krumhansl, Kira; Ezcurra, Juan M; Block, Barbara A

    2013-09-01

    Many species undertake long-distance annual migrations between foraging and reproductive areas. Such migrants depend on the efficient packaging, storage and utilization of energy to succeed. A diverse assemblage of organisms accomplishes this through the use of lipid reserves; yet, it remains unclear whether the migrations of elasmobranchs, which include the largest gill breathers on Earth, depend on such a mechanism. We examine depth records from pop-up satellite archival tags to discern changes in buoyancy as a proxy for energy storage in Eastern Pacific white sharks, and assess whether lipid depletion fuels long-distance (approx. 4000 km) migrations. We develop new algorithms to assess body condition, buoyancy and drift rate during drift dives and validate the techniques using a captive white shark. In the wild, we document a consistent increase in drift rate over the course of all migrations, indicating a decrease in buoyancy caused by the depletion of lipid reserves. These results comprise, to our knowledge, the first assessment of energy storage and budgeting in migrating sharks. The methods provide a basis for further insights into using electronic tags to reveal the energetic strategies of a wide range of elasmobranchs. PMID:23864595

  14. Decoding temporal structure in music and speech relies on shared brain resources but elicits different fine-scale spatial patterns.

    PubMed

    Abrams, Daniel A; Bhatara, Anjali; Ryali, Srikanth; Balaban, Evan; Levitin, Daniel J; Menon, Vinod

    2011-07-01

    Music and speech are complex sound streams with hierarchical rules of temporal organization that become elaborated over time. Here, we use functional magnetic resonance imaging to measure brain activity patterns in 20 right-handed nonmusicians as they listened to natural and temporally reordered musical and speech stimuli matched for familiarity, emotion, and valence. Heart rate variability and mean respiration rates were simultaneously measured and were found not to differ between musical and speech stimuli. Although the same manipulation of temporal structure elicited brain activation level differences of similar magnitude for both music and speech stimuli, multivariate classification analysis revealed distinct spatial patterns of brain responses in the 2 domains. Distributed neuronal populations that included the inferior frontal cortex, the posterior and anterior superior and middle temporal gyri, and the auditory brainstem classified temporal structure manipulations in music and speech with significant levels of accuracy. While agreeing with previous findings that music and speech processing share neural substrates, this work shows that temporal structure in the 2 domains is encoded differently, highlighting a fundamental dissimilarity in how the same neural resources are deployed.

  15. Reflex vasoconstriction in aged human skin increasingly relies on Rho kinase-dependent mechanisms during whole body cooling

    PubMed Central

    Jennings, John D.; Holowatz, Lacy A.; Kenney, W. Larry

    2009-01-01

    Primary human aging may be associated with augmented Rho kinase (ROCK)-mediated contraction of vascular smooth muscle and ROCK-mediated inhibition of nitric oxide synthase (NOS). We hypothesized that the contribution of ROCK to reflex vasoconstriction (VC) is greater in aged skin. Cutaneous VC was elicited by 1) whole body cooling [mean skin temperature (Tsk) = 30.5°C] and 2) local norepinephrine (NE) infusion (1 × 10−6 M). Four microdialysis fibers were placed in the forearm skin of eight young (Y) and eight older (O) subjects for infusion of 1) Ringer solution (control), 2) 3 mM fasudil (ROCK inhibition), 3) 20 mM NG-nitro-l-arginine methyl ester (NOS inhibition), and 4) both ROCK + NOS inhibitors. Red cell flux was measured by laser-Doppler flowmetry over each site. Cutaneous vascular conductance (CVC) was calculated as flux/mean arterial pressure and normalized to baseline CVC (%ΔCVCbaseline). VC was reduced at the control site in O during cooling (Y, −34 ± 3; and O, −18 ± 3%ΔCVCbaseline; P < 0.001) and NE infusion (Y, −53 ± 4, and O, −41 ± 9%ΔCVCbaseline; P = 0.006). Fasudil attenuated VC in both age groups during mild cooling; however, this reduction remained only in O but not in Y skin during moderate cooling (Y, −30 ± 5; and O, −7 ± 1%ΔCVCbaseline; P = 0.016) and was not altered by NOS inhibition. Fasudil blunted NE-mediated VC in both age groups (Y, −23 ± 4; and O, −7 ± 3%ΔCVCbaseline; P < 0.01). Cumulatively, these data indicate that reflex VC is more reliant on ROCK in aged skin such that approximately half of the total VC response to whole body cooling is ROCK dependent. PMID:19717729

  16. Do Adults with Cochlear Implants Rely on Different Acoustic Cues for Phoneme Perception than Adults with Normal Hearing?

    ERIC Educational Resources Information Center

    Moberly, Aaron C.; Lowenstein, Joanna H.; Tarr, Eric; Caldwell-Tarr, Amanda; Welling, D. Bradley; Shahin, Antoine J.; Nittrouer, Susan

    2014-01-01

    Purpose: Several acoustic cues specify any single phonemic contrast. Nonetheless, adult, native speakers of a language share weighting strategies, showing preferential attention to some properties over others. Cochlear implant (CI) signal processing disrupts the salience of some cues: In general, amplitude structure remains readily available, but…

  17. Does maintenance of colour categories rely on language? Evidence to the contrary from a case of semantic dementia.

    PubMed

    Haslam, Catherine; Wills, A J; Haslam, S Alexander; Kay, Janice; Baron, Rachel; McNab, Fiona

    2007-12-01

    Recent neuropsychological evidence, supporting a strong version of Whorfian principles of linguistic relativity, has reinvigorated debate about the role of language in colour categorisation. This paper questions the methodology used in this research and uses a novel approach to examine the unique contribution of language to categorisation behaviour. Results of three investigations are reported. The first required development of objective measures of category coherence and consistency to clarify questions about healthy control performance on the freesorting colour categorisation task used in previous studies. Between-participant consistency was found to be only moderate and the number of colour categories generated was found to vary markedly between individuals. The second study involved longitudinal neuropsychological examination of a patient whose colour categorisation strategy was monitored in the context of a progressive decline in language due to semantic dementia. Performance on measures of category coherence and consistency was found to be relatively stable over time despite a profound decline in the patient's colour language. In a final investigation we demonstrated that, for both the patient and controls, between- and within-participant consistency were higher than expected by (a) random sorting and (b) sorting perceptually similar chips together. These findings indicate that the maintenance of colour categorisation need not depend on language.

  18. Travelling light: white sharks (Carcharodon carcharias) rely on body lipid stores to power ocean-basin scale migration

    PubMed Central

    Del Raye, Gen; Jorgensen, Salvador J.; Krumhansl, Kira; Ezcurra, Juan M.; Block, Barbara A.

    2013-01-01

    Many species undertake long-distance annual migrations between foraging and reproductive areas. Such migrants depend on the efficient packaging, storage and utilization of energy to succeed. A diverse assemblage of organisms accomplishes this through the use of lipid reserves; yet, it remains unclear whether the migrations of elasmobranchs, which include the largest gill breathers on Earth, depend on such a mechanism. We examine depth records from pop-up satellite archival tags to discern changes in buoyancy as a proxy for energy storage in Eastern Pacific white sharks, and assess whether lipid depletion fuels long-distance (approx. 4000 km) migrations. We develop new algorithms to assess body condition, buoyancy and drift rate during drift dives and validate the techniques using a captive white shark. In the wild, we document a consistent increase in drift rate over the course of all migrations, indicating a decrease in buoyancy caused by the depletion of lipid reserves. These results comprise, to our knowledge, the first assessment of energy storage and budgeting in migrating sharks. The methods provide a basis for further insights into using electronic tags to reveal the energetic strategies of a wide range of elasmobranchs. PMID:23864595

  19. The neuroimmune changes induced by cohabitation with an Ehrlich tumor-bearing cage mate rely on olfactory information.

    PubMed

    Alves, Glaucie J; Ribeiro, Alison; Palermo-Neto, João

    2012-01-01

    Cohabitation for 14 days with Ehrlich tumor-bearing mice was shown to increase locomotor activity, to decrease hypothalamic noradrenaline (NA) levels, to increase NA turnover and to decrease innate immune responses and decrease the animals' resistance to tumor growth. Cage mates of a B16F10 melanoma-bearer mice were also reported to show neuroimmune changes. Chemosignals released by Ehrlich tumor-bearing mice have been reported to be relevant for the neutrophil activity changes induced by cohabitation. The present experiment was designed to further analyze the effects of odor cues on neuroimmune changes induced by cohabitation with a sick cage mate. Specifically, the relevance of chemosignals released by an Ehrlich tumor-bearing mouse was assessed on the following: behavior (open-field and plus maze); hypothalamic NA levels and turnover; adrenaline (A) and NA plasmatic levels; and host resistance induced by tumor growth. To comply with such objectives, devices specifically constructed to analyze the influence of chemosignals released from tumor-bearing mice were employed. The results show that deprivation of odor cues released by Ehrlich tumor-bearing mice reversed the behavioral, neurochemical and immune changes induced by cohabitation. Mice use scents for intraspecies communication in many social contexts. Tumors produce volatile organic compounds released into the atmosphere through breath, sweat, and urine. Our results strongly suggest that volatile compounds released by Ehrlich tumor-injected mice are perceived by their conspecifics, inducing the neuroimmune changes reported for cohabitation with a sick companion.

  20. Do Political and Economic Choices Rely on Common Neural Substrates? A Systematic Review of the Emerging Neuropolitics Literature

    PubMed Central

    Krastev, Sekoul; McGuire, Joseph T.; McNeney, Denver; Kable, Joseph W.; Stolle, Dietlind; Gidengil, Elisabeth; Fellows, Lesley K.

    2016-01-01

    The methods of cognitive neuroscience are beginning to be applied to the study of political behavior. The neural substrates of value-based decision-making have been extensively examined in economic contexts; this might provide a powerful starting point for understanding political decision-making. Here, we asked to what extent the neuropolitics literature to date has used conceptual frameworks and experimental designs that make contact with the reward-related approaches that have dominated decision neuroscience. We then asked whether the studies of political behavior that can be considered in this light implicate the brain regions that have been associated with subjective value related to “economic” reward. We performed a systematic literature review to identify papers addressing the neural substrates of political behavior and extracted the fMRI studies reporting behavioral measures of subjective value as defined in decision neuroscience studies of reward. A minority of neuropolitics studies met these criteria and relatively few brain activation foci from these studies overlapped with regions where activity has been related to subjective value. These findings show modest influence of reward-focused decision neuroscience on neuropolitics research to date. Whether the neural substrates of subjective value identified in economic choice paradigms generalize to political choice thus remains an open question. We argue that systematically addressing the commonalities and differences in these two classes of value-based choice will be important in developing a more comprehensive model of the brain basis of human decision-making. PMID:26941703

  1. Numerical analysis of 50 Gbaud homodyne coherent receivers relying on line-coding and injection locking in lasers

    NASA Astrophysics Data System (ADS)

    Xydas, Yannis; Ressopoulos, Constantinos; Bogris, Adonis

    2015-12-01

    We present a numerical analysis of 50 Gbaud coherent detection enabled by injection locked lasers and line coding. The coherent receiver was tested with respect to an ideal receiver for two higher order modulation formats (16-QAM, QPSK) and under diverse operating regimes relating to the slave laser linewidth properties, the injection level and the frequency detuning between the incoming signal and the slave laser. The impact of the slave laser properties and line coding techniques on the receiver performance is highlighted showing that the technique could be used as a practical solution in order to enable low-cost and short reach n × 100 Gb/s Ethernet communication systems with the potential of flexibility in terms of the data rate.

  2. If the results of an article are noteworthy, read the entire article; do not rely on the abstract alone.

    PubMed

    Dal-Ré, R; Castell, M V; García-Puig, J

    2015-11-01

    Clinicians typically update their knowledge by reading articles on the Internet. Easy access to the articles' abstracts and a lack of time to access other information sources creates a risk that therapeutic or diagnostic decisions will be made after reading just the abstracts. Occasionally, however, the abstracts of articles from clinical trials that have not obtained statistically significant differences in the primary study endpoint have reported other positive results, for example, of a secondary endpoint or a subgroup analysis. The article, however, correctly reports all results, including those of the primary endpoint. In the abstract, the safety information of the experimental treatment is usually deficient. The whole article should be read if a clinical decision is to be made.

  3. Embracing Advancement: You Can't Rely on Outside Funding. How to Build a Strong Internal Fundraising Machine

    ERIC Educational Resources Information Center

    Heaton, Paul

    2014-01-01

    In the past 7 years of working at and in community colleges, the author has seen two distinct trends: (1) Community colleges appear to be ushering in a new era of advancement; and (2) Community colleges themselves are often the biggest impediment to successful advancement efforts. Despite millions of grateful learners and business and community…

  4. Postprandial insulin action relies on meal composition and hepatic parasympathetics: dependency on glucose and amino acids: Meal, parasympathetics & insulin action.

    PubMed

    Afonso, Ricardo A; Gaspar, Joana M; Lamarão, Iva; Lautt, W Wayne; Macedo, M Paula

    2016-01-01

    Insulin sensitivity (IS) increases following a meal. Meal composition affects postprandial glucose disposal but still remains unclear which nutrients and mechanisms are involved. We hypothesized that gut-absorbed glucose and amino acids stimulate hepatic parasympathetic nerves, potentiating insulin action. Male Sprague-Dawley rats were 24 h fasted and anesthetized. Two series of experiments were performed. (A) IS was assessed before and after liquid test meal administration (10 ml.kg(-1), intraenteric): glucose + amino acids + lipids (GAL, n=6); glucose (n=5); amino acids (n=5); lipids (n=3); glucose + amino acids (GA, n=9); amino acids + lipids (n=3); and glucose + lipids (n=4). (B) Separately, fasted animals were submitted to hepatic parasympathetic denervation (DEN); IS was assessed before and after GAL (n=4) or GA administration (n=4). (A) Both GAL and GA induced significant insulin sensitization. GAL increased IS from 97.9±6.2 mg glucose/kg bw (fasting) to 225.4±18.3 mg glucose/kg bw (P<0.001; 143.6±26.0% potentiation of IS); GA increased IS from 109.0±6.6 to 240.4±18.0 mg glucose/kg bw (P<0.001; 123.1±13.4% potentiation). None of the other meals potentiated IS. (B) GAL and GA did not induce a significant insulin sensitization in DEN animal. To achieve maximal insulin sensitization following a meal, it is required that gut-absorbed glucose and amino acids trigger a vagal reflex that involves hepatic parasympathetic nerves.

  5. Instructive Bilingualism: Can Bilingual Children with Specific Language Impairment Rely on One Language in Learning a Second One?

    ERIC Educational Resources Information Center

    Armon-Lotem, Sharon

    2010-01-01

    Only a decade ago, a very few researchers considered the study of language disorders in bilingual population worth pursuing. It was mostly argued that there were enough challenges in studying bilingualism, and even more challenges in the study of specific language impairment (SLI). So why complicate things and combine the two domains?

  6. Reducing costs of managing and accessing navigation and ancillary data by relying on the extensive capabilities of NASA's spice system

    NASA Technical Reports Server (NTRS)

    Semenov, Boris V.; Acton, Charles H., Jr.; Bachman, Nathaniel J.; Elson, Lee S.; Wright, Edward D.

    2005-01-01

    The SPICE system of navigation and ancillary data possesses a number of traits that make its use in modern space missions of all types highly cost efficient. The core of the system is a software library providing API interfaces for storing and retrieving such data as trajectories, orientations, time conversions, and instrument geometry parameters. Applications used at any stage of a mission life cycle can call SPICE APIs to access this data and compute geometric quantities required for observation planning, engineering assessment and science data analysis. SPICE is implemented in three different languages, supported on 20+ computer environments, and distributed with complete source code and documentation. It includes capabilities that are extensively tested by everyday use in many active projects and are applicable to all types of space missions - flyby, orbiters, observatories, landers and rovers. While a customer's initial SPICE adaptation for the first mission or experiment requires a modest effort, this initial effort pays off because adaptation for subsequent missions/experiments is just a small fraction of the initial investment, with the majority of tools based on SPICE requiring no or very minor changes.

  7. Testis specific serine/threonine protein kinase 4 (TSSK4) leads to cell apoptosis relying on its kinase activity.

    PubMed

    Wang, Xiao-li; Wei, You-heng; Fu, Guo-long; Yu, Long

    2015-04-01

    Testis specific serine/threonine protein kinase 4 (TSSK4) belongs to the TSSK family, and its members play an important role in spermatogenesis and/or spermiogenesis. Mouse TSSK4 has been reported to be expressed exclusively in the testis and can maintain its kinase activity through autophosphorylation at Thr-197. However, its biological function remains poorly understood. Here we found that GFP-TSSK4-overexpressed HeLa cells showed apoptotic bodies, indicating TSSK4 can lead to apoptosis in vitro. Furthermore, TSSK4 induced apoptosis in different cell lines including HeLa, Cos-7 and H1299 tested by flow cytometry but not its kinase-dead mutant TSSK4-K54M. TSSK4 knockout mice showed increased testes weight and decreased apoptotic spermatogonia and spermatocytes at 21st day after birth tested by TUNEL technology. So TSSK4 was able to induce cell apoptosis in vitro depending on its kinase activity, which leads to abnormal testes weight and apoptosis, shedding light on its function in the process of spermatogenesis and/or spermiogenesis.

  8. Attending to multiple objects relies on both feature- and dimension-based control mechanisms: Evidence from human electrophysiology.

    PubMed

    Töllner, Thomas; Conci, Markus; Müller, Hermann J; Mazza, Veronica

    2016-10-01

    Numerous everyday search tasks require humans to attentionally select and temporally store more than one object present in the visual environment. Recently, several enumeration studies sought to isolate the mechanisms underlying multiple object processing by means of electrophysiological measures, which led to a more fine-grained picture as to which processing stages are modulated by object numerosity. One critical limitation that most of these studies share is that they used stimulus designs in which multiple targets were exclusively defined by the same feature value. Accordingly, it remains an open issue whether these findings generalize to search scenarios in which multiple targets are physically not identical. To systematically address this issue, we introduced three target context conditions in which multiple targets were defined randomly by (1) the same feature (sF), (2) different features within the same dimension (dFsD), or (3) different features across dimensions (dD). Our findings revealed that participants' ability to enumerate multiple targets was remarkably influenced by inter-target relationships, with fastest responses for sF trials, slowest responses for dD trials, and responses of intermediate speed for dFsD trials. Our electrophysiological analyses disclosed that one source of this response slowing was feature-based and originated from the stage of attentional selection (as indexed by PCN waves), whereas another source was dimension-based and associated with working memory processes (as indexed by P3b waves). Overall, our results point to a significant role of physical inter-target relationships in multiple object processing-a factor that has been largely neglected in most studies on enumeration. PMID:27299342

  9. Questions ouvertes/questions fermees: une dichotomie qui appelle une analyse critique (Open Questions/Closed Questions: A Dichotomy that Calls for a Critical Analysis).

    ERIC Educational Resources Information Center

    Vinter, Shirley; Bried, Charles

    1998-01-01

    Among the strategies used by the adult to engage the child in a linguistic interaction, those involving questioning occupy a central position. One of the parameters usually taken into account to differentiate the type of questions directed to the child is the opposition between closed (i.e., yes/no) and open-ended questions. The relevance of that…

  10. Systeme des fautes et correction phonetique des Anglais qui apprennent le francais (System of Errors and Phonetic Correction of English Speakers Learning French)

    ERIC Educational Resources Information Center

    Lebrun, Claire

    1975-01-01

    This article provides the results of an investigation of the system of pronunciation faults of English speakers learning French, and describes means of correction based on the verbo-tonal system. (Text is in French.) (CLK)

  11. Quand le malheur frappe les bénéficiaires de la sécurité du revenu. Sur qui peuvent-ils s’appuyer ?

    PubMed Central

    Tousignant, Michel; Caron, Jean

    2013-01-01

    Cette étude analyse les conditions de réalisation du soutien social dans les quartiers de Saint-Henri et de la Pointe Saint-Charles, en comparant un groupe de 61 prestataires de la sécurité du revenu avec un échantillon de 21 personnes de la population vivant au-dessus du seuil de la pauvreté, et en fonction du degré de détresse dans chaque groupe. Elle vise également à décrire comment une adversité vécue par les prestataires avec ou sans détresse vient briser ou modifier le réseau de soutien. Les résultats indiquent que le réseau social est moins fiable en présence de détresse qu’en son absence, que les personnes en détresse se sont vues plus fréquemment refuser du soutien ou être abandonnées et qu’elles ont davantage de personnes nuisibles dans leur entourage. De plus, les événements vécus comportent souvent une atteinte à leur réputation, des menaces, des trahisons et des refus à un droit légitime. Les personnes en détresse sont aussi davantage isolées. PMID:16505926

  12. La sténose urétérale post infectieuse et la mégacalicose: un train qui en cache un autre

    PubMed Central

    Sine, Babacar; Bagayogo, Ndeye Aissatou; Fall, Boubacar; Sow, Yaya; Thiam, Amath; Sarr, Alioune; Zakou, Abdou Razak Hamidou; Faye, Samba Thiapato; Diao, Babacar; Fall, Papa Ahmed; Ndoye, Alain khassim

    2015-01-01

    La mégacalicose est une uropathie malformative rare caractérisée par une dilatation non obstructive des calices avec hypoplasie de la médullaire rénale. Nous rapportons un cas de mégacalicose associée à une sténose urétérale bilatérale d'origine infectieuse. PMID:26977241

  13. Ad vesice dolorem et ad eos qui urinam non faciunt (For bladder pain and when a person cannot urinate): nephrological disorders in Anglo-Saxon medicine.

    PubMed

    D'Aronco, Maria A

    2009-01-01

    The attitude of 19th century (and even of 20th century) scholars toward medieval and, particularly, Anglo-Saxon medicine has been of severe criticism. According to them it was filled with superstition and stupidities. However, in these last fifty years research has proved that, compared with the Continent, Anglo-Saxon England was not a backwater. At the end of the ninth century, medical compendia in Old English began to appear, similar in structure and contents to the Latin dynamidia and to the Latin herbals. These medical treatises were written in the vernacular of the Anglo-Saxons, not in Latin, the western European language for all significant and valuable works on medicine. Bladder, kidney and urinating problems are mentioned throughout the Old English medical treatises together with their cures, that is remedies from herbs and animals. These texts contain no theoretical reflections, only very concise descriptions of symptoms (pain in the bladder, in the kidneys, difficulty in urinating etc.), while prognosis is limited to affirmations such as "he will heal very quickly," "soon there will be no pain," "it will soon be healed," etc. Remedies are made basically out of a body of medicinal plants and materials which can be traced to Greek and Roman medicine. The remedies from plants reflect a wide rational and practical knowledge of medicinal herbs. As a matter of fact, not only there is no amuletic use of plants, but most of the herbs that appear in these recipes have diuretic or analgesic properties and have been in use for centuries. PMID:20013730

  14. Class Acts: How Teachers Awaken Potential = Docentes al habla: Revelar a los alumnos el tesoro de su potencial = Performances d'enseignants: Comment eveiller un potential qui dort.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    This publication presents portraits of nine teachers from Argentina, Brazil, Canada, France, Jordan, Myanmar, New Zealand, Senegal, and Trinidad and Tobago who are opening up young minds and nurturing their potential. The portraits describe how these teachers created an educational situation in which students could thrive and grow. Some of the…

  15. The Effect of Text Translation on Perceived Musical Tension in Debussy's "Noel des enfants qui n'ont plus de maisons"

    ERIC Educational Resources Information Center

    Hackworth, Rhonda S.; Fredrickson, William E.

    2010-01-01

    The primary focus of the present study was to investigate the effect participants' (N = 100) knowledge of a text translation may have on their perceived musical tension while listening to a piece of choral music sung in another language. When examining the graphs that show the group mean responses of the participants, control (without text…

  16. Dendritic cell-mediated vaccination relies on interleukin-4 receptor signaling to avoid tissue damage after Leishmania major infection of BALB/c mice.

    PubMed

    Masic, Anita; Hurdayal, Ramona; Nieuwenhuizen, Natalie E; Brombacher, Frank; Moll, Heidrun

    2012-01-01

    Prevention of tissue damages at the site of Leishmania major inoculation can be achieved if the BALB/c mice are systemically given L. major antigen (LmAg)-loaded bone marrow-derived dendritic cells (DC) that had been exposed to CpG-containing oligodeoxynucleotides (CpG ODN). As previous studies allowed establishing that interleukin-4 (IL-4) is involved in the redirection of the immune response towards a type 1 profile, we were interested in further exploring the role of IL-4. Thus, wild-type (wt) BALB/c mice or DC-specific IL-4 receptor alpha (IL-4Rα)-deficient (CD11c(cre)IL-4Rα(-/lox)) BALB/c mice were given either wt or IL-4Rα-deficient LmAg-loaded bone marrow-derived DC exposed or not to CpG ODN prior to inoculation of 2×10⁵ stationary-phase L. major promastigotes into the BALB/c footpad. The results provide evidence that IL4/IL-4Rα-mediated signaling in the vaccinating DC is required to prevent tissue damage at the site of L. major inoculation, as properly conditioned wt DC but not IL-4Rα-deficient DC were able to confer resistance. Furthermore, uncontrolled L. major population size expansion was observed in the footpad and the footpad draining lymph nodes of CD11c(cre)IL-4Rα(-/lox) mice immunized with CpG ODN-exposed LmAg-loaded IL-4Rα-deficient DC, indicating the influence of IL-4Rα-mediated signaling in host DC to control parasite replication. In addition, no footpad damage occurred in BALB/c mice that were systemically immunized with LmAg-loaded wt DC doubly exposed to CpG ODN and recombinant IL-4. We discuss these findings and suggest that the IL4/IL4Rα signaling pathway could be a key pathway to trigger when designing vaccines aimed to prevent damaging processes in tissues hosting intracellular microorganisms.

  17. Chip-interleaved optical code division multiple access relying on a photon-counting iterative successive interference canceller for free-space optical channels.

    PubMed

    Zhou, Xiaolin; Zheng, Xiaowei; Zhang, Rong; Hanzo, Lajos

    2013-07-01

    In this paper, we design a novel Poisson photon-counting based iterative successive interference cancellation (SIC) scheme for transmission over free-space optical (FSO) channels in the presence of both multiple access interference (MAI) as well as Gamma-Gamma atmospheric turbulence fading, shot-noise and background light. Our simulation results demonstrate that the proposed scheme exhibits a strong MAI suppression capability. Importantly, an order of magnitude of BER improvements may be achieved compared to the conventional chip-level optical code-division multiple-access (OCDMA) photon-counting detector.

  18. A photon-counting spatial-diversity-and-multiplexing MIMO scheme for Poisson atmospheric channels relying on Q-ary PPM.

    PubMed

    Zhou, Xiaolin; Zhang, Dingchen; Zhang, Rong; Hanzo, Lajos

    2012-11-19

    A novel Photon-Counting Spatial-Diversity-and-Multiplexing (PC-SDM) scheme is proposed for high-speed Free-Space Optical (FSO) transmission over shot-noise limited Poisson channels experiencing turbulence-induced fading. In particular, Iterative Parallel Interference Cancellation (Iter-PIC) aided Q-ary Pulse Position Modulation (Q-PPM) is employed. Simulation results demonstrate that our proposed scheme exhibits a high integrity and a high throughput, while mitigating the effects of multi-stream interference and background radiation noise.

  19. A unique quinolineboronic acid-based supramolecular structure that relies on double intermolecular B-N bonds for self-assembly in solid state and in solution.

    PubMed

    Zhang, Yanling; Li, Minyong; Chandrasekaran, Sekar; Gao, Xingming; Fang, Xikui; Lee, Hsiau-Wei; Hardcastle, Kenneth; Yang, Jenny; Wang, Binghe

    2007-04-16

    The boronic acid functional group plays very important roles in sugar recognition, catalysis, organic synthesis, and supramolecular assembly. Therefore, understanding the unique properties of this functional group is very important. 8-Quinolineboronic acid (8-QBA) is found to be capable of self-assembling in solid state through a unique intermolecular B-N bond mechanism reinforced by intermolecular boronic anhydride formation, π-π stacking, and hydrogen bond formation. NMR NOE and diffusion studies indicate that intermolecular B-N interaction also exists in solution with 8-QBA. In contrast, a positional isomer of 8-QBA, 5-quinolineboronic acid (5-QBA) showed very different behaviors in crystal packing and in solution and therefore different supramolecular network. Understanding the structural features of this unique 8-QBA assembly could be very helpful for the future design of new sugar sensors, molecular catalysts, and supramolecular assemblies. PMID:18414645

  20. A unique quinolineboronic acid-based supramolecular structure that relies on double intermolecular B-N bonds for self-assembly in solid state and in solution

    PubMed Central

    Zhang, Yanling; Li, Minyong; Chandrasekaran, Sekar; Gao, Xingming; Fang, Xikui; Lee, Hsiau-Wei; Hardcastle, Kenneth; Yang, Jenny; Wang, Binghe

    2007-01-01

    The boronic acid functional group plays very important roles in sugar recognition, catalysis, organic synthesis, and supramolecular assembly. Therefore, understanding the unique properties of this functional group is very important. 8-Quinolineboronic acid (8-QBA) is found to be capable of self-assembling in solid state through a unique intermolecular B-N bond mechanism reinforced by intermolecular boronic anhydride formation, π-π stacking, and hydrogen bond formation. NMR NOE and diffusion studies indicate that intermolecular B-N interaction also exists in solution with 8-QBA. In contrast, a positional isomer of 8-QBA, 5-quinolineboronic acid (5-QBA) showed very different behaviors in crystal packing and in solution and therefore different supramolecular network. Understanding the structural features of this unique 8-QBA assembly could be very helpful for the future design of new sugar sensors, molecular catalysts, and supramolecular assemblies. PMID:18414645

  1. Do clinicians decide relying primarily on Bayesians principles or on Gestalt perception? Some pearls and pitfalls of Gestalt perception in medicine.

    PubMed

    Cervellin, Gianfranco; Borghi, Loris; Lippi, Giuseppe

    2014-08-01

    Clinical judgment is a foundation of medical practice and lies at the heart of a physician's knowledge, expertise and skill. Although clinical judgment is an active part of all medical fields, thus including diagnosis and therapy, communication and decision making, it is still poorly defined. It can be considered a synthesis of intuition (mainly based on Gestalt principles) and an analytical approach. Gestalt perception finds its rationale in the evidence that perception of any given object or experience exhibits intrinsic qualities that cannot be completely reduced to visual, auditory, tactile, olfactory, or gustatory components. Thus, perceptions are not constructed in a "bottom-up" fashion from such elements, but are instead globally perceived, in a more "top-down" fashion. Gestalt perception, if cautiously and carefully combined with structured (techno)logical tools, would permit one to defoliate the often too-many-branches built diagnostic trees, and help physicians to better develop their competency. On the other hand, the practice of evidence-based medicine lies in the integration of individual clinical expertise and judgment with the best available external clinical evidence from systematic research. This article is aimed at providing some general concepts about Gestalt perception, and to discuss some aspects of clinical practice potentially influenced by this approach. PMID:24610565

  2. Transcriptomic analysis by RNA-seq reveals AP-1 pathway as key regulator that green tea may rely on to inhibit lung tumorigenesis.

    PubMed

    Pan, Jing; Zhang, Qi; Xiong, Donghai; Vedell, Peter; Yan, Ying; Jiang, Hui; Cui, Peng; Ding, Feng; Tichelaar, Jay W; Wang, Yian; Lubet, Ronald A; You, Ming

    2014-01-01

    Green tea is a promising chemopreventive agent for lung cancer. Multiple signaling events have been reported, however, the relative importance of these mechanisms in mediating the chemopreventive function of green tea is unclear. In the present study, to examine the involvement of AP-1 in green tea polyphenols induced tumor inhibition, human NSCLC cell line H1299 and mouse SPON 10 cells were identified as AP-1 dependent, as these two lines exhibit high constitutive AP-1 activity, and when TAM67 expression was induced with doxycycline, cell growth was inhibited and correlated with suppressed AP-1 activity. RNA-seq was used to determine the global transcriptional effects of AP-1 inhibition and also uncover the possible involvement of AP-1 in tea polyphenols induced chemoprevention. TAM67 mediated changes in gene expression were identified, and within down-regulated genes, AP-1 was identified as a key transcription regulator. RNA-seq analysis revealed that Polyphenon E-treated cells shared 293 commonly down-regulated genes within TAM67 expressing H1299 cells, and by analysis of limited Chip-seq data, over 10% of the down-regulated genes contain a direct AP-1 binding site, indicating that Polyphenon E elicits chemopreventive activity by regulating AP-1 target genes. Conditional TAM67 expressing transgenic mice and NSCLC cell lines were used to further confirm that the chemopreventive activity of green tea is AP-1 dependent. Polyphenon E lost its chempreventive function both in vitro and in vivo when AP-1 was inhibited, indicating that AP-1 inhibition is a major pathway through which green tea exhibits chemopreventive effects.

  3. A functional network of the tumor suppressors APC, hDlg, and PTEN, that relies on recognition of specific PDZ-domains.

    PubMed

    Sotelo, Natalia S; Valiente, Miguel; Gil, Anabel; Pulido, Rafael

    2012-08-01

    APC and PTEN are tumor suppressor proteins that bind through their C-termini to the PDZ domain containing-hDlg scaffolding protein. We have found that co-expression of PTEN and hDlg enhanced the negative regulation of the PI3K/Akt pathway by PTEN, indicating the physiologic importance of these interactions. APC and PTEN share other PDZ domain containing-interacting partners, including the MAGI scaffolding proteins and the MAST family of protein kinases. Mutational analysis revealed that the C-terminal PDZ-binding motifs from APC and PTEN were differentially recognized by distinct PDZ domains. APC bound to the three PDZ domains from hDlg, whereas PTEN mainly bound to PDZ-2/hDlg. This indicates the existence of overlapping, but distinct PDZ-domain recognition patterns by APC and PTEN. Furthermore, a ternary complex formed by APC, PTEN, and hDlg was detected, suggesting that hDlg may serve as a platform to bring in proximity APC and PTEN tumor suppressor activities. In line with this, tumor-related mutations targeting the PDZ-2/hDlg domain diminished its interaction with APC and PTEN. Our results expand the PDZ-domain counterparts for the tumor suppressor APC, show that APC and PTEN share PDZ-domain partners but have individual molecular determinants for specific recognition of PDZ domains, and suggest the participation of the tumor suppressors APC, PTEN, and hDlg in PDZ-domain interaction networks which may be relevant in oncogenesis.

  4. Chloroflexi CL500-11 Populations That Predominate Deep-Lake Hypolimnion Bacterioplankton Rely on Nitrogen-Rich Dissolved Organic Matter Metabolism and C1 Compound Oxidation.

    PubMed

    Denef, Vincent J; Mueller, Ryan S; Chiang, Edna; Liebig, James R; Vanderploeg, Henry A

    2015-12-18

    The Chloroflexi CL500-11 clade contributes a large proportion of the bacterial biomass in the oxygenated hypolimnia of deep lakes worldwide, including the world's largest freshwater system, the Laurentian Great Lakes. Traits that allow CL500-11 to thrive and its biogeochemical role in these environments are currently unknown. Here, we found that a CL500-11 population was present mostly in offshore waters along a transect in ultraoligotrophic Lake Michigan (a Laurentian Great Lake). It occurred throughout the water column in spring and only in the hypolimnion during summer stratification, contributing up to 18.1% of all cells. Genome reconstruction from metagenomic data suggested an aerobic, motile, heterotrophic lifestyle, with additional energy being gained through carboxidovory and methylovory. Comparisons to other available streamlined freshwater genomes revealed that the CL500-11 genome contained a disproportionate number of cell wall/capsule biosynthesis genes and the most diverse spectrum of genes involved in the uptake of dissolved organic matter (DOM) substrates, particularly peptides. In situ expression patterns indicated the importance of DOM uptake and protein/peptide turnover, as well as type I and type II carbon monoxide dehydrogenase and flagellar motility. Its location in the water column influenced its gene expression patterns the most. We observed increased bacteriorhodopsin gene expression and a response to oxidative stress in surface waters compared to its response in deep waters. While CL500-11 carries multiple adaptations to an oligotrophic lifestyle, its investment in motility, its large cell size, and its distribution in both oligotrophic and mesotrophic lakes indicate its ability to thrive under conditions where resources are more plentiful. Our data indicate that CL500-11 plays an important role in nitrogen-rich DOM mineralization in the extensive deep-lake hypolimnion habitat.

  5. Do clinicians decide relying primarily on Bayesians principles or on Gestalt perception? Some pearls and pitfalls of Gestalt perception in medicine.

    PubMed

    Cervellin, Gianfranco; Borghi, Loris; Lippi, Giuseppe

    2014-08-01

    Clinical judgment is a foundation of medical practice and lies at the heart of a physician's knowledge, expertise and skill. Although clinical judgment is an active part of all medical fields, thus including diagnosis and therapy, communication and decision making, it is still poorly defined. It can be considered a synthesis of intuition (mainly based on Gestalt principles) and an analytical approach. Gestalt perception finds its rationale in the evidence that perception of any given object or experience exhibits intrinsic qualities that cannot be completely reduced to visual, auditory, tactile, olfactory, or gustatory components. Thus, perceptions are not constructed in a "bottom-up" fashion from such elements, but are instead globally perceived, in a more "top-down" fashion. Gestalt perception, if cautiously and carefully combined with structured (techno)logical tools, would permit one to defoliate the often too-many-branches built diagnostic trees, and help physicians to better develop their competency. On the other hand, the practice of evidence-based medicine lies in the integration of individual clinical expertise and judgment with the best available external clinical evidence from systematic research. This article is aimed at providing some general concepts about Gestalt perception, and to discuss some aspects of clinical practice potentially influenced by this approach.

  6. Therapeutic expectations: Dentistry relies less on dental plaque as a major etiological factor OR On the dental needs of young orthodontic patients (12-20 years old)

    PubMed Central

    Consolaro, Alberto; Nardoni, Daniele Nóbrega; Capelozza, Leopoldino; Franco, Paulo Henrique X.; Cappellozza, José Antônio Z.

    2016-01-01

    In Brazilian cities and states governed efficiently with wealth ethically administered, carious and periodontal diseases have prevalence rates similar to those found in socially developed European countries. This shift in reality, noticed over the last 15 years, reflects on changes in the etiological factors related to patients' major expectations and needs - especially young and orthodontic patients - which turn out to be a result of dental trauma, malocclusion, facial aspect, dental agenesis and iatrogenesis. Under such conditions, patients begin to appreciate the value of tooth position, color and shape, their smile and function: details become relevant. Carious and periodontal diseases remain an issue, not only from a preventive prospect, but also from a curative one. Nevertheless, it should be noted that changes and development are inevitable, and we should be prepared to contribute to the wellbeing of people, particularly regarding their novel needs and expectations. PMID:27007757

  7. Therapeutic expectations: Dentistry relies less on dental plaque as a major etiological factor. OR On the dental needs of young orthodontic patients (12-20 years old).

    PubMed

    Consolaro, Alberto; Nardoni, Daniele Nóbrega; Capelozza Filho, Leopoldino; Franco, Paulo Henrique X; Cappellozza, José Antônio Z

    2016-01-01

    In Brazilian cities and states governed efficiently with wealth ethically administered, carious and periodontal diseases have prevalence rates similar to those found in socially developed European countries. This shift in reality, noticed over the last 15 years, reflects on changes in the etiological factors related to patients' major expectations and needs--especially young and orthodontic patients--which turn out to be a result of dental trauma, malocclusion, facial aspect, dental agenesis and iatrogenesis. Under such conditions, patients begin to appreciate the value of tooth position, color and shape, their smile and function: details become relevant. Carious and periodontal diseases remain an issue, not only from a preventive prospect, but also from a curative one. Nevertheless, it should be noted that changes and development are inevitable, and we should be prepared to contribute to the wellbeing of people, particularly regarding their novel needs and expectations. PMID:27007757

  8. Apicoplast-Localized Lysophosphatidic Acid Precursor Assembly Is Required for Bulk Phospholipid Synthesis in Toxoplasma gondii and Relies on an Algal/Plant-Like Glycerol 3-Phosphate Acyltransferase.

    PubMed

    Amiar, Souad; MacRae, James I; Callahan, Damien L; Dubois, David; van Dooren, Giel G; Shears, Melanie J; Cesbron-Delauw, Marie-France; Maréchal, Eric; McConville, Malcolm J; McFadden, Geoffrey I; Yamaryo-Botté, Yoshiki; Botté, Cyrille Y

    2016-08-01

    Most apicomplexan parasites possess a non-photosynthetic plastid (the apicoplast), which harbors enzymes for a number of metabolic pathways, including a prokaryotic type II fatty acid synthesis (FASII) pathway. In Toxoplasma gondii, the causative agent of toxoplasmosis, the FASII pathway is essential for parasite growth and infectivity. However, little is known about the fate of fatty acids synthesized by FASII. In this study, we have investigated the function of a plant-like glycerol 3-phosphate acyltransferase (TgATS1) that localizes to the T. gondii apicoplast. Knock-down of TgATS1 resulted in significantly reduced incorporation of FASII-synthesized fatty acids into phosphatidic acid and downstream phospholipids and a severe defect in intracellular parasite replication and survival. Lipidomic analysis demonstrated that lipid precursors are made in, and exported from, the apicoplast for de novo biosynthesis of bulk phospholipids. This study reveals that the apicoplast-located FASII and ATS1, which are primarily used to generate plastid galactolipids in plants and algae, instead generate bulk phospholipids for membrane biogenesis in T. gondii. PMID:27490259

  9. Protection from oxidative stress relies mainly on derepression of OxyR-dependent KatB and Dps in Shewanella oneidensis.

    PubMed

    Jiang, Yaoming; Dong, Yangyang; Luo, Qixia; Li, Ning; Wu, Genfu; Gao, Haichun

    2014-01-01

    Shewanella thrives in redox-stratified environments where accumulation of H2O2 becomes inevitable because of the chemical oxidation of reduced metals, sulfur species, or organic molecules. As a research model, the representative species Shewanella oneidensis has been extensively studied for its response to various stresses. However, little progress has been made toward an understanding of the physiological and genetic responses of this bacterium to oxidative stress, which is critically relevant to its application as a dissimilatory metal-reducing bacterium. In this study, we systematically investigated the mechanism underlying the response to H2O2 at cellular, genomic, and molecular levels. Using transcriptional profiling, we found that S. oneidensis is hypersensitive to H2O2 in comparison with Escherichia coli, and well-conserved defense genes such as ahpCF, katB, katG, and dps appear to form the first line of defense, whereas iron-sulfur-protecting proteins may not play a significant role. Subsequent identification and characterization of an analogue of the E. coli oxyR gene revealed that S. oneidensis OxyR is the master regulator that mediates the bacterial response to H2O2-induced oxidative stress by directly repressing or activating the defense genes. The sensitivity of S. oneidensis to H2O2 is likely attributable to the lack of an inducible manganese import mechanism during stress. To cope with stress, major strategies that S. oneidensis adopts include rapid removal of the oxidant and restriction of intracellular iron concentrations, both of which are achieved predominantly by derepression of the katB and dps genes.

  10. "When I Need to Do Something Else with the Other Children, Then I Can Rely on Her": Teaching Assistants Working with Socially Disadvantaged Students

    ERIC Educational Resources Information Center

    Nemec, Zbynek; Šimácková-Laurencíková, Klára; Hájková, Vanda; Strnadová, Iva

    2015-01-01

    The article presents the results of a research study focused on the role of teaching assistants involved with socially disadvantaged students. Forty-six interviews were conducted with school principals, teachers, teaching assistants and socially disadvantaged students from 10 schools in the Czech Republic. The authors used thematic analysis of the…

  11. No transfer between conditions in balance training regimes relying on tasks with different postural demands: Specificity effects of two different serious games.

    PubMed

    Naumann, Tim; Kindermann, Stefan; Joch, Michael; Munzert, Jörn; Reiser, Mathias

    2015-03-01

    Despite the increasing use of video games involving whole body movements to enhance postural control in health prevention and rehabilitation, there is no consistent proof that training effects actually transfer to other balance tasks. The present study aimed to determine whether training effects on two different video-game-based training devices were task-specific or could be transferred to either postural control in quiet stance or to performance on the other device. 37 young healthy adults were split into three groups: two intervention groups that trained for 30min on either the Nintendo(®) Wii Fit Balance Board or the MFT Challenge Disc(®) three times per week for 4 weeks and a control group that received no training. All games require participants to control virtual avatars by shifting the center of mass in different directions. Both devices differ in their physical properties. The Balance Board provides a stable surface, whereas the Challenge Disc can be tilted in all directions. Dependent variables were the game scores on both devices and the center of pressure (COP) displacements measured via force plate. At posttest, both intervention groups showed significant increases in performance on the trained games compared to controls. However, there were no relevant transfer effects to performance on the untrained device and no changes in COP path length in quiet stance. These results suggest that training effects on both devices are highly specific and do not transfer to tasks with different postural demands.

  12. Student Information Systems Demystified: The Increasing Demand for Accurate, Timely Data Means Schools and Districts Are Relying Heavily on SIS Technologies

    ERIC Educational Resources Information Center

    McIntire, Todd

    2004-01-01

    Student information systems, one of the first applications of computer technology in education, are undergoing a significant transition yet again. The first major shift in SIS technologies occurred about 15 years ago when they evolved from mainframe programs to client-server solutions. Now, vendors across the board are offering centralized…

  13. When the Stakes Are High, Can We Rely on Value-Added? Exploring the Use of Value-Added Models to Inform Teacher Workforce Decisions

    ERIC Educational Resources Information Center

    Goldhaber, Dan

    2010-01-01

    The formula is simple: Highly effective teachers equal student academic success. Yet, the physics of American education is anything but. Thus, the question facing education reformers is how can teacher effectiveness be accurately measured in order to improve the teacher workforce? Given the demand for objective, quantitative measures of teacher…

  14. Sex biased spatial strategies relying on the integration of multimodal cues in a rat model of schizophrenia: impairment in predicting future context?

    PubMed

    Bertholet, Léa; Meunier, Cécile; Preissmann, Delphine; Schenk, Françoise

    2014-04-01

    Male and female Wistar rats were treated postnatally (PND 5-16) with BSO (l-buthionine-(S,R)-sulfoximine) to provide a rat model of schizophrenia based on transient glutathione deficit. In the watermaze, BSO-treated male rats perform very efficiently in conditions where a diversity of visual information is continuously available during orientation trajectories [1]. Our hypothesis is that the treatment impairs proactive strategies anticipating future sensory information, while supporting a tight visual adjustment on memorized snapshots, i.e. compensatory reactive strategies. To test this hypothesis, BSO rats' performance was assessed in two conditions using an 8-arm radial maze task: a semi-transparent maze with no available view on the environment from maze centre [2], and a modified 2-parallel maze known to induce a neglect of the parallel pair in normal rats [3-5]. Male rats, but not females, were affected by the BSO treatment. In the semi-transparent maze, BSO males expressed a higher error rate, especially in completing the maze after an interruption. In the 2-parallel maze shape, BSO males, unlike controls, expressed no neglect of the parallel arms. This second result was in accord with a reactive strategy using accurate memory images of the contextual environment instead of a representation based on integrating relative directions. These results are coherent with a treatment-induced deficit in proactive decision strategy based on multimodal cognitive maps, compensated by accurate reactive adaptations based on the memory of local configurations. Control females did not express an efficient proactive capacity in the semi-transparent maze, neither did they show the significant neglect of the parallel arms, which might have masked the BSO induced effect. Their reduced sensitivity to BSO treatment is discussed with regard to a sex biased basal cognitive style.

  15. Lens ion homeostasis relies on the assembly and/or stability of large connexin 46 gap junction plaques on the broad sides of differentiating fiber cells

    PubMed Central

    Cheng, Catherine; Nowak, Roberta B.; Gao, Junyuan; Sun, Xiurong; Biswas, Sondip K.; Lo, Woo-Kuen; Mathias, Richard T.

    2015-01-01

    The eye lens consists of layers of tightly packed fiber cells, forming a transparent and avascular organ that is important for focusing light onto the retina. A microcirculation system, facilitated by a network of gap junction channels composed of connexins 46 and 50 (Cx46 and Cx50), is hypothesized to maintain and nourish lens fiber cells. We measured lens impedance in mice lacking tropomodulin 1 (Tmod1, an actin pointed-end capping protein), CP49 (a lens-specific intermediate filament protein), or both Tmod1 and CP49. We were surprised to find that simultaneous loss of Tmod1 and CP49, which disrupts cytoskeletal networks in lens fiber cells, results in increased gap junction coupling resistance, hydrostatic pressure, and sodium concentration. Protein levels of Cx46 and Cx50 in Tmod1−/−;CP49−/− double-knockout (DKO) lenses were unchanged, and electron microscopy revealed normal gap junctions. However, immunostaining and quantitative analysis of three-dimensional confocal images showed that Cx46 gap junction plaques are smaller and more dispersed in DKO differentiating fiber cells. The localization and sizes of Cx50 gap junction plaques in DKO fibers were unaffected, suggesting that Cx46 and Cx50 form homomeric channels. We also demonstrate that gap junction plaques rest in lacunae of the membrane-associated actin-spectrin network, suggesting that disruption of the actin-spectrin network in DKO fibers may interfere with gap junction plaque accretion into micrometer-sized domains or alter the stability of large plaques. This is the first work to reveal that normal gap junction plaque localization and size are associated with normal lens coupling conductance. PMID:25740157

  16. ERPs show that classroom-instructed late second language learners rely on the same prosodic cues in syntactic parsing as native speakers.

    PubMed

    Nickels, Stefanie; Opitz, Bertram; Steinhauer, Karsten

    2013-12-17

    The loss of brain plasticity after a 'critical period' in childhood has often been argued to prevent late language learners from using the same neurocognitive mechanisms as native speakers and, therefore, from attaining a high level of second language (L2) proficiency [7,11]. However, more recent behavioral and electrophysiological research has challenged this 'Critical Period Hypothesis', demonstrating that even late L2 learners can display native-like performance and brain activation patterns [17], especially after longer periods of immersion in an L2 environment. Here we use event-related potentials (ERPs) to show that native-like processing can also be observed in the largely under-researched domain of speech prosody - even when L2 learners are exposed to their second language almost exclusively in a classroom setting. Participants listened to spoken sentences whose prosodic boundaries would either cooperate or conflict with the syntactic structure. Previous work had shown that this paradigm is difficult for elderly native speakers, however, German L2 learners of English showed very similar ERP components for on-line prosodic phrasing as well as for prosody-syntax mismatches (garden path effects) as the control group of native speakers. These data suggest that L2 immersion is not always necessary to master complex L2 speech processing in a native-like way.

  17. Life-threatening misdiagnosis of bulbar onset myasthenia gravis as a motor neuron disease: How much can one rely on exaggerated deep tendon reflexes

    PubMed Central

    Basiri, Keivan; Ansari, Behnaz; Okhovat, Ali Asghar

    2015-01-01

    The autoimmune disease myasthenia gravis (MG), can mimic a variety of neurological disorders leading to a delay in diagnosis and treatment. On occasions, misdiagnosis of MG could lead to unnecessary therapeutic interventions. We report the case of a 50 year-old man, in whom MG was mistaken for motor neuron disease (MND). Subsequently, correct diagnosis and optimal management resulted in saving his life and significant improvement in his functional status. We discuss the importance of considering MG as one of the potential differential diagnoses among cases of new onset or recurrent unexplained bulbar symptoms, despite exaggerated deep tendon reflexes. Also, a literature review on the misdiagnosis of MG and the potential pitfalls in MG diagnosis are discussed. PMID:25802827

  18. At the Scene of the Crime: Law Enforcement Agencies and Lawmakers Rely on Studies from the Institute for Social Research To Inform Policy-Making.

    ERIC Educational Resources Information Center

    Maurer, Rachel

    1998-01-01

    The University of New Mexico's Institute for Social Research operates eight centers that conduct policy-related research on criminal justice, criminology, delinquency, and social problems. Projects have focused on inequities in criminal sentencing in New Mexico, juveniles' access to and use of guns, New Mexico's need for a juvenile prison, and the…

  19. Apicoplast-Localized Lysophosphatidic Acid Precursor Assembly Is Required for Bulk Phospholipid Synthesis in Toxoplasma gondii and Relies on an Algal/Plant-Like Glycerol 3-Phosphate Acyltransferase

    PubMed Central

    Callahan, Damien L.; Dubois, David; van Dooren, Giel G.; Shears, Melanie J.; Cesbron-Delauw, Marie-France; Maréchal, Eric; McConville, Malcolm J.; McFadden, Geoffrey I.; Yamaryo-Botté, Yoshiki; Botté, Cyrille Y.

    2016-01-01

    Most apicomplexan parasites possess a non-photosynthetic plastid (the apicoplast), which harbors enzymes for a number of metabolic pathways, including a prokaryotic type II fatty acid synthesis (FASII) pathway. In Toxoplasma gondii, the causative agent of toxoplasmosis, the FASII pathway is essential for parasite growth and infectivity. However, little is known about the fate of fatty acids synthesized by FASII. In this study, we have investigated the function of a plant-like glycerol 3-phosphate acyltransferase (TgATS1) that localizes to the T. gondii apicoplast. Knock-down of TgATS1 resulted in significantly reduced incorporation of FASII-synthesized fatty acids into phosphatidic acid and downstream phospholipids and a severe defect in intracellular parasite replication and survival. Lipidomic analysis demonstrated that lipid precursors are made in, and exported from, the apicoplast for de novo biosynthesis of bulk phospholipids. This study reveals that the apicoplast-located FASII and ATS1, which are primarily used to generate plastid galactolipids in plants and algae, instead generate bulk phospholipids for membrane biogenesis in T. gondii. PMID:27490259

  20. Staphylococcus haemolyticus prophage ΦSH2 endolysin relies on Cysteine, Histidine-dependent Amidohydrolases/Peptidases activity for lysis ‘from without’

    PubMed Central

    Schmelcher, Mathias; Korobova, Olga; Schischkova, Nina; Kiseleva, Natalia; Kopylov, Paul; Pryamchuk, Sergey; Donovan, David M.; Abaev, Igor

    2014-01-01

    Staphylococcus aureus is an important pathogen, with methicillin-resistant (MRSA) and multi-drug resistant strains becoming increasingly prevalent in both human and veterinary clinics. S. aureus causing bovine mastitis yields high annual losses to the dairy industry. Conventional treatment of mastitis by broad range antibiotics is often not successful and may contribute to development of antibiotic resistance. Bacteriophage endolysins present a promising new source of antimicrobials. The endolysin of prophage ΦSH2 of Staphylococcus haemolyticus strain JCSC1435 (ΦSH2 lysin) is a peptidoglycan hydrolase consisting of two catalytic domains (CHAP and amidase) and an SH3b cell wall binding domain. In this work, we demonstrated its lytic activity against live staphylococcal cells and investigated the contribution of each functional module to bacterial lysis by testing a series of deletion constructs in zymograms and turbidity reduction assays. The CHAP domain exhibited three-fold higher activity than the full length protein and optimum activity in physiological saline. This activity was further enhanced by the presence of bivalent calcium ions. The SH3b domain was shown to be required for full activity of the complete ΦSH2 lysin. The full length enzyme and the CHAP domain showed activity against multiple staphylococcal strains, including MRSA strains, mastitis isolates, and CoNS. PMID:23026556

  1. On the causal mechanisms of stereotype threat: can skills that don't rely heavily on working memory still be threatened?

    PubMed

    Beilock, Sian L; Jellison, William A; Rydell, Robert J; McConnell, Allen R; Carr, Thomas H

    2006-08-01

    Recent work suggests that stereotype threat (ST) harms performance by reducing available working memory capacity. Is this the only mechanism by which ST can occur? Three experiments examined ST's impact on expert golf putting, which is not harmed when working memory is reduced but is hurt when attention is allocated to proceduralized processes that normally run outside working memory. Experiment 1 showed that well learned golf putting is susceptible to ST. Experiments 2 and 3 demonstrated that giving expert golfers a secondary task eliminates ST-induced impairment. Distracting attention away from the stereotype-related behavior eliminates the harmful impact of negative stereotype activation. These results are consistent with explicit monitoring theories of choking under pressure, which suggest that performance degradation can occur when too much attention is allocated to processes that usually run more automatically. Thus, ST alters information processing in multiple ways, inducing performance decrements for different reasons in different tasks. PMID:16861310

  2. Dithienobenzothiadiazole-based conjugated polymer: processing solvent-relied interchain aggregation and device performances in field-effect transistors and polymer solar cells.

    PubMed

    Huang, Jun; Zhu, Yongxiang; Chen, Junwu; Zhang, Lianjie; Peng, Junbiao; Cao, Yong

    2014-11-01

    DTfBT-Th(3), a new conjugated polymer based on dithienobenzothiadiazole and terthiophene, possesses a bandgap of ≈1.86 eV and a HOMO level of -5.27 eV. Due to strong interchain aggregation, DTfBT-Th(3) can not be well dissolved in chloro-benzene (CB) and o-dichlorobenzene (DCB) at room temperature (RT), but the polymer can be processed from hot CB and DCB solutions of ≈100 °C. In CB, with a lower solvation ability, a certain polymer chain aggregation can be preserved, even in hot solution. DTfBT-Th(3) displays a field-effect hole mobility of 0.55 cm(2) V(-1) s(-1) when fabricated from hot CB solution, which is higher than that of the device processed from hot DCB (0.16 cm(2) V(-1) s(-1) In DTfBT-Th(3) -based polymer solar cells, a good power conversion efficiency from 5.37% to 6.67% can be achieved with 150-300 nm thick active layers casted from hot CB solution, while the highest efficiency for hot DCB-processed solar cells is only 5.07%. The results demonstrate that using a solvent with a lower solvation ability, as a "wet control" process, is beneficial to preserve strong interchain aggregation of a conjugated polymer during solution processing, showing great potential to improve its performances in optoelectronic devices.

  3. System-Events Toolbox--Activating Urban Places for Social Cohesion through Designing a System of Events That Relies on Local Resources

    ERIC Educational Resources Information Center

    Fassi, Davide; Motter, Roberta

    2014-01-01

    This paper is a reflection on the use of public spaces in towns and the development of a system-events toolbox to activate them towards social cohesion. It is the result of a 1 year action research developed together with POLIMI DESIS Lab of the Department of Design to develop design solutions to open up the public spaces of the campus to the…

  4. Adenovirus E4-ORF3-dependent relocalization of TIF1{alpha} and TIF1{gamma} relies on access to the Coiled-Coil motif

    SciTech Connect

    Vink, Elizabeth I.; Yondola, Mark A.; Wu, Kai; Hearing, Patrick

    2012-01-20

    The adenovirus E4-ORF3 protein promotes viral replication by relocalizing cellular proteins into nuclear track structures, interfering with potential anti-viral activities. E4-ORF3 targets transcriptional intermediary factor 1 alpha (TIF1{alpha}), but not homologous TIF1{beta}. Here, we introduce TIF1{gamma} as a novel E4-ORF3-interacting partner. E4-ORF3 relocalizes endogenous TIF1{gamma} in virus-infected cells in vivo and binds to TIF1{gamma} in vitro. We used the homologous nature, yet differing binding capabilities, of these proteins to study how E4-ORF3 targets proteins for track localization. We mapped the ability of E4-ORF3 to interact with specific TIF1 subdomains, demonstrating that E4-ORF3 interacts with the Coiled-Coil domains of TIF1{alpha}, TIF1{beta}, and TIF1{gamma}, and that the C-terminal half of TIF1{beta} interferes with this interaction. The results of E4-ORF3-directed TIF1 protein relocalization assays performed in vivo were verified using coimmunoprecipitation assays in vitro. These results suggest that E4-ORF3 targets proteins for relocalization through a loosely homologous sequence dependent on accessibility.

  5. Growth of triple-negative breast cancer cells relies upon coordinate autocrine expression of the proinflammatory cytokines IL-6 and IL-8.

    PubMed

    Hartman, Zachary C; Poage, Graham M; den Hollander, Petra; Tsimelzon, Anna; Hill, Jamal; Panupinthu, Nattapon; Zhang, Yun; Mazumdar, Abhijit; Hilsenbeck, Susan G; Mills, Gordon B; Brown, Powel H

    2013-06-01

    Triple-negative breast cancers (TNBC) are aggressive with no effective targeted therapies. A combined database analysis identified 32 inflammation-related genes differentially expressed in TNBCs and 10 proved critical for anchorage-independent growth. In TNBC cells, an LPA-LPAR2-EZH2 NF-κB signaling cascade was essential for expression of interleukin (IL)-6, IL-8, and CXCL1. Concurrent inhibition of IL-6 and IL-8 expression dramatically inhibited colony formation and cell survival in vitro and stanched tumor engraftment and growth in vivo. A Cox multivariable analysis of patient specimens revealed that IL-6 and IL-8 expression predicted patient survival times. Together these findings offer a rationale for dual inhibition of IL-6/IL-8 signaling as a therapeutic strategy to improve outcomes for patients with TNBCs.

  6. Protection from Oxidative Stress Relies Mainly on Derepression of OxyR-Dependent KatB and Dps in Shewanella oneidensis

    PubMed Central

    Jiang, Yaoming; Dong, Yangyang; Luo, Qixia; Li, Ning; Wu, Genfu

    2014-01-01

    Shewanella thrives in redox-stratified environments where accumulation of H2O2 becomes inevitable because of the chemical oxidation of reduced metals, sulfur species, or organic molecules. As a research model, the representative species Shewanella oneidensis has been extensively studied for its response to various stresses. However, little progress has been made toward an understanding of the physiological and genetic responses of this bacterium to oxidative stress, which is critically relevant to its application as a dissimilatory metal-reducing bacterium. In this study, we systematically investigated the mechanism underlying the response to H2O2 at cellular, genomic, and molecular levels. Using transcriptional profiling, we found that S. oneidensis is hypersensitive to H2O2 in comparison with Escherichia coli, and well-conserved defense genes such as ahpCF, katB, katG, and dps appear to form the first line of defense, whereas iron-sulfur-protecting proteins may not play a significant role. Subsequent identification and characterization of an analogue of the E. coli oxyR gene revealed that S. oneidensis OxyR is the master regulator that mediates the bacterial response to H2O2-induced oxidative stress by directly repressing or activating the defense genes. The sensitivity of S. oneidensis to H2O2 is likely attributable to the lack of an inducible manganese import mechanism during stress. To cope with stress, major strategies that S. oneidensis adopts include rapid removal of the oxidant and restriction of intracellular iron concentrations, both of which are achieved predominantly by derepression of the katB and dps genes. PMID:24214945

  7. Denver Reengineers: By Relying More on Vendors and Technology, Jo Sarling Explains How the Denver Public Library Shifted Resources to the Public

    ERIC Educational Resources Information Center

    Sarling, Jo

    2005-01-01

    This article gives details of the developments and changes in the Denver Public Library (DPL). Through a review of advancements in technology, vendor capabilities, staffing levels and talent, as well as outsourcing opportunities, DPL reinvented its workflow and processing. The result? The once giant stacks of books, CDs, videos, and DVDs waiting…

  8. Sex biased spatial strategies relying on the integration of multimodal cues in a rat model of schizophrenia: impairment in predicting future context?

    PubMed

    Bertholet, Léa; Meunier, Cécile; Preissmann, Delphine; Schenk, Françoise

    2014-04-01

    Male and female Wistar rats were treated postnatally (PND 5-16) with BSO (l-buthionine-(S,R)-sulfoximine) to provide a rat model of schizophrenia based on transient glutathione deficit. In the watermaze, BSO-treated male rats perform very efficiently in conditions where a diversity of visual information is continuously available during orientation trajectories [1]. Our hypothesis is that the treatment impairs proactive strategies anticipating future sensory information, while supporting a tight visual adjustment on memorized snapshots, i.e. compensatory reactive strategies. To test this hypothesis, BSO rats' performance was assessed in two conditions using an 8-arm radial maze task: a semi-transparent maze with no available view on the environment from maze centre [2], and a modified 2-parallel maze known to induce a neglect of the parallel pair in normal rats [3-5]. Male rats, but not females, were affected by the BSO treatment. In the semi-transparent maze, BSO males expressed a higher error rate, especially in completing the maze after an interruption. In the 2-parallel maze shape, BSO males, unlike controls, expressed no neglect of the parallel arms. This second result was in accord with a reactive strategy using accurate memory images of the contextual environment instead of a representation based on integrating relative directions. These results are coherent with a treatment-induced deficit in proactive decision strategy based on multimodal cognitive maps, compensated by accurate reactive adaptations based on the memory of local configurations. Control females did not express an efficient proactive capacity in the semi-transparent maze, neither did they show the significant neglect of the parallel arms, which might have masked the BSO induced effect. Their reduced sensitivity to BSO treatment is discussed with regard to a sex biased basal cognitive style. PMID:24406722

  9. Short-term retention of a single word relies on retrieval from long-term memory when both rehearsal and refreshing are disrupted.

    PubMed

    Rose, Nathan S; Buchsbaum, Bradley R; Craik, Fergus I M

    2014-07-01

    Many working memory (WM) models propose that the focus of attention (or primary memory) has a capacity limit of one to four items, and therefore, that performance on WM tasks involves retrieving some items from long-term (or secondary) memory (LTM). In the present study, we present evidence suggesting that recall of even one item on a WM task can involve retrieving it from LTM. The WM task required participants to make a deep (living/nonliving) or shallow ("e"/no "e") level-of-processing (LOP) judgment on one word and to recall the word after a 10-s delay on each trial. During the delay, participants either rehearsed the word or performed an easy or a hard math task. When the to-be-remembered item could be rehearsed, recall was fast and accurate. When it was followed by a math task, recall was slower, error-prone, and benefited from a deeper LOP at encoding, especially for the hard math condition. The authors suggest that a covert-retrieval mechanism may have refreshed the item during easy math, and that the hard math condition shows that even a single item cannot be reliably held in WM during a sufficiently distracting task--therefore, recalling the item involved retrieving it from LTM. Additionally, performance on a final free recall (LTM) test was better for items recalled following math than following rehearsal, suggesting that initial recall following math involved elaborative retrieval from LTM, whereas rehearsal did not. The authors suggest that the extent to which performance on WM tasks involves retrieval from LTM depends on the amounts of disruption to both rehearsal and covert-retrieval/refreshing maintenance mechanisms. PMID:24500778

  10. Trastuzumab-resistant cells rely on a HER2-PI3K-FoxO-survivin axis and are sensitive to PI3K inhibitors.

    PubMed

    Chakrabarty, Anindita; Bhola, Neil E; Sutton, Cammie; Ghosh, Ritwik; Kuba, María Gabriela; Dave, Bhuvanesh; Chang, Jenny C; Arteaga, Carlos L

    2013-02-01

    The antibody trastuzumab is approved for treatment of patients with HER2 (ERBB2)-overexpressing breast cancer. A significant fraction of these tumors are either intrinsically resistant or acquire resistance rendering the drug ineffective. The development of resistance has been attributed to failure of the antibody to inhibit phosphoinositide 3-kinase (PI3K), which is activated by the HER2 network. Herein, we examined the effects of PI3K blockade in trastuzumab-resistant breast cancer cell lines. Treatment with the pan-PI3K inhibitor XL147 and trastuzumab reduced proliferation and pAKT levels, triggering apoptosis of trastuzumab-resistant cells. Compared with XL147 alone, the combination exhibited a superior antitumor effect against trastuzumab-resistant tumor xenografts. Furthermore, treatment with XL147 and trastuzumab reduced the cancer stem-cell (CSC) fraction within trastuzumab-resistant cells both in vitro and in vivo. These effects were associated with FoxO-mediated inhibition of transcription of the antiapoptosis gene survivin (BIRC5) and the CSC-associated cytokine interleukin-8. RNA interference-mediated or pharmacologic inhibition of survivin restored sensitivity to trastuzumab in resistant cells. In a cohort of patients with HER2-overexpressing breast cancer treated with trastuzumab, higher pretreatment tumor levels of survivin RNA correlated with poor response to therapy. Together, our results suggest that survivin blockade is required for therapeutic responses to trastuzumab and that by combining trastuzumab and PI3K inhibitors, CSCs can be reduced within HER2(+) tumors, potentially preventing acquired resistance to anti-HER2 therapy.

  11. Activated T Cell Trans-Endothelial Migration Relies on Myosin-IIA Contractility for Squeezing the Cell Nucleus through Endothelial Cell Barriers

    PubMed Central

    Jacobelli, Jordan; Estin Matthews, Miriam; Chen, Stephanie; Krummel, Matthew F.

    2013-01-01

    Following activation, T cells are released from lymph nodes to traffic via the blood to effector sites. The re-entry of these activated T cells into tissues represents a critical step for them to carry out local effector functions. Here we have assessed defects in effector T cells that are acutely depleted in Myosin-IIA (MyoIIA) and show a T cell intrinsic requirement for this motor to facilitate the diapedesis step of extravasation. We show that MyoIIA accumulates at the rear of T cells undergoing trans-endothelial migration. T cells can extend protrusions and project a substantial portion of their cytoplasm through the endothelial wall in the absence of MyoIIA. However, this motor protein plays a crucial role in allowing T cells to complete the movement of their relatively rigid nucleus through the endothelial junctions. In vivo, this defect manifests as poor entry into lymph nodes, tumors and into the spinal cord, during tissue-specific autoimmunity, but not the spleen. This suggests that therapeutic targeting of this molecule may allow for differential attenuation of tissue-specific inflammatory responses. PMID:24069389

  12. The Two Rivers of Public Education: Why Our Representative Democracy Relies on Both Individualism and Community to Be Delivered through Its Public Schools

    ERIC Educational Resources Information Center

    Draayer, Donald

    2011-01-01

    America is blessed with two river systems that feed and nourish the country by their periodic flooding. One mighty river is "individualism" (the entrepreneurial drive to advance and make a difference). The other river is "community" (wherein communal interests strengthen the whole community over the parts). Monitoring and regulating these two…

  13. On the causal mechanisms of stereotype threat: can skills that don't rely heavily on working memory still be threatened?

    PubMed

    Beilock, Sian L; Jellison, William A; Rydell, Robert J; McConnell, Allen R; Carr, Thomas H

    2006-08-01

    Recent work suggests that stereotype threat (ST) harms performance by reducing available working memory capacity. Is this the only mechanism by which ST can occur? Three experiments examined ST's impact on expert golf putting, which is not harmed when working memory is reduced but is hurt when attention is allocated to proceduralized processes that normally run outside working memory. Experiment 1 showed that well learned golf putting is susceptible to ST. Experiments 2 and 3 demonstrated that giving expert golfers a secondary task eliminates ST-induced impairment. Distracting attention away from the stereotype-related behavior eliminates the harmful impact of negative stereotype activation. These results are consistent with explicit monitoring theories of choking under pressure, which suggest that performance degradation can occur when too much attention is allocated to processes that usually run more automatically. Thus, ST alters information processing in multiple ways, inducing performance decrements for different reasons in different tasks.

  14. The biosynthesis of mycolic acids in Mycobacterium tuberculosis relies on multiple specialized elongation complexes interconnected by specific protein-protein interactions.

    PubMed

    Veyron-Churlet, Romain; Bigot, Sarah; Guerrini, Olivier; Verdoux, Sébastien; Malaga, Wladimir; Daffé, Mamadou; Zerbib, Didier

    2005-11-01

    Tuberculosis kills about two million people every year and remains one of the leading causes of mortality worldwide. As a result of the increasing antibiotic resistance of Mycobacterium tuberculosis (Mtb) strains, there is an urgent need for new antitubercular drugs. Several efficient antibiotics, including isoniazid, specifically target the fatty acid synthase-II (FAS-II) complex of mycolic acid biosynthesis. We have previously shown that there are protein-protein interactions between the components of FAS-II that are essential for mycobacterial survival. We have now looked at the potential partners of FAS-II, mtFabD, the methyltransferases MmaAs, and Pks13. A combination of yeast two-hybrid and co-immunoprecipitation experiments showed that mtFabD interacts with each beta-ketoacyl-synthase (KasA, KasB and mtFabH) and with the core of FAS-II (InhA and MabA). The methyltransferases have a greater affinity for KasA and KasB than for mtFabH, suggesting that modifications on the meromycolic chains may occur during their elongation. Finally, Pks13, which catalyzes the final Claisen condensation of mycolic acids, interacts specifically with KasB. These data allowed us to determine the architecture of the multiple specialized FAS-II complexes, giving us insights into the organization of the complete mycolic acids biosynthesis. Our studies suggest a new and crucial interaction (KasB-Pks13) as a putative target for peptidomimetic antibiotics. PMID:16213523

  15. T-cell help dependence of memory CD8+ T-cell expansion upon vaccinia virus challenge relies on CD40 signaling.

    PubMed

    Bedenikovic, Gregor; Crouse, Josh; Oxenius, Annette

    2014-01-01

    Due to their capacity to differentiate into long-lived memory cells, CD8(+) T cells are able to resolve subsequent infections faster than during the primary response. Among other factors, CD4(+) T cells play a crucial role during primary and secondary CD8(+) T-cell responses. However, the timing and mechanisms by which they influence CD8(+) T cells may differ in primary and secondary responses. Here, we demonstrate that during both primary and secondary vaccinia virus infection, CD4(+) T cells are necessary to promote CD8(+) T-cell responses. While CD4(+) T cells contributed to memory CD8(+) T-cell development, they were even more important during memory recall responses during challenge, as absence of CD4(+) T cells during challenge resulted in markedly decreased proliferation and increased apoptosis. T-cell help during primary and secondary responses was mediated via CD40 signaling, with DCs being an integral part of that pathway. As opposed to primary CD8(+) T-cell responses where only a combination of agonistic CD40 signaling and provision of IL-2 could substitute for T-cell help, agonistic CD40 triggering alone was sufficient to rescue memory CD8(+) T-cell responses in absence of T-cell help in the context of vaccinia virus infection.

  16. Chloroflexi CL500-11 Populations That Predominate Deep-Lake Hypolimnion Bacterioplankton Rely on Nitrogen-Rich Dissolved Organic Matter Metabolism and C1 Compound Oxidation

    PubMed Central

    Mueller, Ryan S.; Chiang, Edna; Liebig, James R.; Vanderploeg, Henry A.

    2015-01-01

    The Chloroflexi CL500-11 clade contributes a large proportion of the bacterial biomass in the oxygenated hypolimnia of deep lakes worldwide, including the world's largest freshwater system, the Laurentian Great Lakes. Traits that allow CL500-11 to thrive and its biogeochemical role in these environments are currently unknown. Here, we found that a CL500-11 population was present mostly in offshore waters along a transect in ultraoligotrophic Lake Michigan (a Laurentian Great Lake). It occurred throughout the water column in spring and only in the hypolimnion during summer stratification, contributing up to 18.1% of all cells. Genome reconstruction from metagenomic data suggested an aerobic, motile, heterotrophic lifestyle, with additional energy being gained through carboxidovory and methylovory. Comparisons to other available streamlined freshwater genomes revealed that the CL500-11 genome contained a disproportionate number of cell wall/capsule biosynthesis genes and the most diverse spectrum of genes involved in the uptake of dissolved organic matter (DOM) substrates, particularly peptides. In situ expression patterns indicated the importance of DOM uptake and protein/peptide turnover, as well as type I and type II carbon monoxide dehydrogenase and flagellar motility. Its location in the water column influenced its gene expression patterns the most. We observed increased bacteriorhodopsin gene expression and a response to oxidative stress in surface waters compared to its response in deep waters. While CL500-11 carries multiple adaptations to an oligotrophic lifestyle, its investment in motility, its large cell size, and its distribution in both oligotrophic and mesotrophic lakes indicate its ability to thrive under conditions where resources are more plentiful. Our data indicate that CL500-11 plays an important role in nitrogen-rich DOM mineralization in the extensive deep-lake hypolimnion habitat. PMID:26682860

  17. No transfer between conditions in balance training regimes relying on tasks with different postural demands: Specificity effects of two different serious games.

    PubMed

    Naumann, Tim; Kindermann, Stefan; Joch, Michael; Munzert, Jörn; Reiser, Mathias

    2015-03-01

    Despite the increasing use of video games involving whole body movements to enhance postural control in health prevention and rehabilitation, there is no consistent proof that training effects actually transfer to other balance tasks. The present study aimed to determine whether training effects on two different video-game-based training devices were task-specific or could be transferred to either postural control in quiet stance or to performance on the other device. 37 young healthy adults were split into three groups: two intervention groups that trained for 30min on either the Nintendo(®) Wii Fit Balance Board or the MFT Challenge Disc(®) three times per week for 4 weeks and a control group that received no training. All games require participants to control virtual avatars by shifting the center of mass in different directions. Both devices differ in their physical properties. The Balance Board provides a stable surface, whereas the Challenge Disc can be tilted in all directions. Dependent variables were the game scores on both devices and the center of pressure (COP) displacements measured via force plate. At posttest, both intervention groups showed significant increases in performance on the trained games compared to controls. However, there were no relevant transfer effects to performance on the untrained device and no changes in COP path length in quiet stance. These results suggest that training effects on both devices are highly specific and do not transfer to tasks with different postural demands. PMID:25791870

  18. Induction of Photosynthetic Carbon Fixation in Anoxia Relies on Hydrogenase Activity and Proton-Gradient Regulation-Like1-Mediated Cyclic Electron Flow in Chlamydomonas reinhardtii1

    PubMed Central

    Bailleul, Benjamin; Berne, Nicolas

    2015-01-01

    The model green microalga Chlamydomonas reinhardtii is frequently subject to periods of dark and anoxia in its natural environment. Here, by resorting to mutants defective in the maturation of the chloroplastic oxygen-sensitive hydrogenases or in Proton-Gradient Regulation-Like1 (PGRL1)-dependent cyclic electron flow around photosystem I (PSI-CEF), we demonstrate the sequential contribution of these alternative electron flows (AEFs) in the reactivation of photosynthetic carbon fixation during a shift from dark anoxia to light. At light onset, hydrogenase activity sustains a linear electron flow from photosystem II, which is followed by a transient PSI-CEF in the wild type. By promoting ATP synthesis without net generation of photosynthetic reductants, the two AEF are critical for restoration of the capacity for carbon dioxide fixation in the light. Our data also suggest that the decrease in hydrogen evolution with time of illumination might be due to competition for reduced ferredoxins between ferredoxin-NADP+ oxidoreductase and hydrogenases, rather than due to the sensitivity of hydrogenase activity to oxygen. Finally, the absence of the two alternative pathways in a double mutant pgrl1 hydrogenase maturation factor G-2 is detrimental for photosynthesis and growth and cannot be compensated by any other AEF or anoxic metabolic responses. This highlights the role of hydrogenase activity and PSI-CEF in the ecological success of microalgae in low-oxygen environments. PMID:25931521

  19. Induction of Photosynthetic Carbon Fixation in Anoxia Relies on Hydrogenase Activity and Proton-Gradient Regulation-Like1-Mediated Cyclic Electron Flow in Chlamydomonas reinhardtii.

    PubMed

    Godaux, Damien; Bailleul, Benjamin; Berne, Nicolas; Cardol, Pierre

    2015-06-01

    The model green microalga Chlamydomonas reinhardtii is frequently subject to periods of dark and anoxia in its natural environment. Here, by resorting to mutants defective in the maturation of the chloroplastic oxygen-sensitive hydrogenases or in Proton-Gradient Regulation-Like1 (PGRL1)-dependent cyclic electron flow around photosystem I (PSI-CEF), we demonstrate the sequential contribution of these alternative electron flows (AEFs) in the reactivation of photosynthetic carbon fixation during a shift from dark anoxia to light. At light onset, hydrogenase activity sustains a linear electron flow from photosystem II, which is followed by a transient PSI-CEF in the wild type. By promoting ATP synthesis without net generation of photosynthetic reductants, the two AEF are critical for restoration of the capacity for carbon dioxide fixation in the light. Our data also suggest that the decrease in hydrogen evolution with time of illumination might be due to competition for reduced ferredoxins between ferredoxin-NADP(+) oxidoreductase and hydrogenases, rather than due to the sensitivity of hydrogenase activity to oxygen. Finally, the absence of the two alternative pathways in a double mutant pgrl1 hydrogenase maturation factor G-2 is detrimental for photosynthesis and growth and cannot be compensated by any other AEF or anoxic metabolic responses. This highlights the role of hydrogenase activity and PSI-CEF in the ecological success of microalgae in low-oxygen environments. PMID:25931521

  20. Systeme de fautes et correction phonetique par la methode verbo-tonale des francophones belges qui apprenent l'espagnol (Phonetic Correction and the Verbo-tonal Method for Teaching Spanish to French-speaking Belgians)

    ERIC Educational Resources Information Center

    Sarmiento Padilla, Jose

    1974-01-01

    Describes experiments in the field of phonetic correction. Several techniques used at the University of Mons for teaching Spanish pronunciation to French-speaking Belgians are explained. (Text is in French.) (PMP)

  1. Are the Kids Alright? What's Shaping the Attitudes, Values and Behaviour of our Young People? = Les enfants se portent-ils bien? Qu'est-ce qui faconne les attitudes, les valeurs et le comportement de nos jeunes?

    ERIC Educational Resources Information Center

    Theilheimer, Ish, Ed.

    1992-01-01

    This theme issue explores the behavior of teenagers. "Are the Kids Alright?" (Ish Theilheimer) develops a perspective on the subject of teen behavior, noting that a growing number of young people demonstrate discontent, alienation, aggression, violence, and antisocial behavior, and that a growing underclass of children is likely to fail. The…

  2. L’explosion intravésicale au cours des procédures de résection endoscopique: Un incident dangereux qui peut être évité

    PubMed Central

    Anzaoui, Jihad El; Abakka, Najib; El harrech, Younes; Ghoundale, Omar; Touiti, Driss; Lahkim, Mohammed; Fihri, Jawad Fassi; Bakzaza, Walid; Mejdane, Abdelhadi

    2013-01-01

    Résumé Les explosions survenant au cours des manœuvres endoscopiques urologiques sont rares et dangereuses. Elles sont dues à une production d’hydrogène par hydrolyse de l’eau lors des procédés de coagulation et de section. L’hydrogène devient très combustible une fois mélangé avec l’oxygène ambiant. Nous rapportons un cas d’explosion intravésicale au cours d’une résection transurethrale d’une tumeur de la vessie et nous exposons, par une revue de littérature, les différentes théories physiopathologiques et les moyens de prévention. PMID:23914274

  3. L'enseignement des langues: Pour qui? Pour quoi? (Language Teaching: For Whom? For What Purpose?). Proceedings of the annual Symposium of the Canadian Association of Applied Linguistics (7th, Sherbrooke, Canada, May 6, 1976). Publication B-62.

    ERIC Educational Resources Information Center

    Taggart, Gilbert, Ed.

    These 16 papers in French and English deal with questions related to the purpose of learning a language, one's native language as well as a second one. Specifically, the presentations deal with the following topics: (1) consideration of learners' needs; (2) the usefulness of learning English in Quebec; (3) the tension between knowledge and…

  4. Les inconvénients de perdre du poids

    PubMed Central

    Bosomworth, N. John

    2012-01-01

    Résumé Objectif Explorer les raisons pour lesquelles la perte de poids à long terme échoue la plupart du temps et évaluer les conséquences de diverses trajectoires pondérales, y compris la stabilité, la perte et le gain. Source des données Les études qui évaluent les paramètres pondéraux dans la population sont en majorité observationnelles. Des données probantes de niveau I ont été publiées pour évaluer l’influence des interventions relatives au poids sur la mortalité et la qualité de vie. Message principal Seulement un petit pourcentage des personnes qui désirent perdre du poids réussissent à le faire de manière durable. La mortalité est la plus faible chez les personnes se situant dans la catégorie de poids élevé-normal et surpoids. La trajectoire pondérale la plus sécuritaire est la stabilité du poids avec une optimisation de la condition physique et métabolique. Il est démontré que la mortalité est plus faible chez les personnes ayant des comorbidités reliées à l’obésité si elles perdent du poids. Il est aussi établi que la qualité de vie sur le plan de la santé est meilleure chez les personnes obèses qui perdent du poids. Par contre, la perte de poids chez une personne obèse autrement en santé est associée à une mortalité accrue. Conclusion La perte de poids est recommandable seulement chez les personnes qui ont des comorbidités reliées à l’obésité. Les personnes obèses en santé qui veulent perdre du poids devraient être informées qu’il peut y avoir des risques à le faire. Une stratégie qui se traduit par un indice de masse corporelle stable avec une condition physique et métabolique optimisée, peu importe le poids, est l’option d’intervention la plus sécuritaire en ce qui concerne le poids.

  5. Into the Curriculum. Art: Pueblo Storyteller Figures [and] Physical Education: Games That Rely on Feet [and] Reading/Language Arts: Movie Reviews [and] Reading/Language Arts: Reader's Choice [and] Science: Float or Sink [and] Social Studies: Buildings and Designs.

    ERIC Educational Resources Information Center

    Crane, Jean; Rains, Annette

    1996-01-01

    Presents six curriculum guides for art, physical education, reading/language arts, science, and social studies. Each guide identifies library media skills objectives; curriculum objectives; grade levels; print and nonprint resources; instructional roles; the activity; and procedures for completion, evaluation, and follow-up activities. (AEF)

  6. Efficient Translation of Pelargonium line pattern virus RNAs Relies on a TED-Like 3´-Translational Enhancer that Communicates with the Corresponding 5´-Region through a Long-Distance RNA-RNA Interaction

    PubMed Central

    Blanco-Pérez, Marta; Pérez-Cañamás, Miryam; Ruiz, Leticia; Hernández, Carmen

    2016-01-01

    Cap-independent translational enhancers (CITEs) have been identified at the 3´-terminal regions of distinct plant positive-strand RNA viruses belonging to families Tombusviridae and Luteoviridae. On the bases of their structural and/or functional requirements, at least six classes of CITEs have been defined whose distribution does not correlate with taxonomy. The so-called TED class has been relatively under-studied and its functionality only confirmed in the case of Satellite tobacco necrosis virus, a parasitic subviral agent. The 3´-untranslated region of the monopartite genome of Pelargonium line pattern virus (PLPV), the recommended type member of a tentative new genus (Pelarspovirus) in the family Tombusviridae, was predicted to contain a TED-like CITE. Similar CITEs can be anticipated in some other related viruses though none has been experimentally verified. Here, in the first place, we have performed a reassessment of the structure of the putative PLPV-TED through in silico predictions and in vitro SHAPE analysis with the full-length PLPV genome, which has indicated that the presumed TED element is larger than previously proposed. The extended conformation of the TED is strongly supported by the pattern of natural sequence variation, thus providing comparative structural evidence in support of the structural data obtained by in silico and in vitro approaches. Next, we have obtained experimental evidence demonstrating the in vivo activity of the PLPV-TED in the genomic (g) RNA, and also in the subgenomic (sg) RNA that the virus produces to express 3´-proximal genes. Besides other structural features, the results have highlighted the key role of long-distance kissing-loop interactions between the 3´-CITE and 5´-proximal hairpins for gRNA and sgRNA translation. Bioassays of CITE mutants have confirmed the importance of the identified 5´-3´ RNA communication for viral infectivity and, moreover, have underlined the strong evolutionary constraints that may operate on genome stretches with both regulatory and coding functions. PMID:27043436

  7. Efficient Translation of Pelargonium line pattern virus RNAs Relies on a TED-Like 3´-Translational Enhancer that Communicates with the Corresponding 5´-Region through a Long-Distance RNA-RNA Interaction.

    PubMed

    Blanco-Pérez, Marta; Pérez-Cañamás, Miryam; Ruiz, Leticia; Hernández, Carmen

    2016-01-01

    Cap-independent translational enhancers (CITEs) have been identified at the 3´-terminal regions of distinct plant positive-strand RNA viruses belonging to families Tombusviridae and Luteoviridae. On the bases of their structural and/or functional requirements, at least six classes of CITEs have been defined whose distribution does not correlate with taxonomy. The so-called TED class has been relatively under-studied and its functionality only confirmed in the case of Satellite tobacco necrosis virus, a parasitic subviral agent. The 3´-untranslated region of the monopartite genome of Pelargonium line pattern virus (PLPV), the recommended type member of a tentative new genus (Pelarspovirus) in the family Tombusviridae, was predicted to contain a TED-like CITE. Similar CITEs can be anticipated in some other related viruses though none has been experimentally verified. Here, in the first place, we have performed a reassessment of the structure of the putative PLPV-TED through in silico predictions and in vitro SHAPE analysis with the full-length PLPV genome, which has indicated that the presumed TED element is larger than previously proposed. The extended conformation of the TED is strongly supported by the pattern of natural sequence variation, thus providing comparative structural evidence in support of the structural data obtained by in silico and in vitro approaches. Next, we have obtained experimental evidence demonstrating the in vivo activity of the PLPV-TED in the genomic (g) RNA, and also in the subgenomic (sg) RNA that the virus produces to express 3´-proximal genes. Besides other structural features, the results have highlighted the key role of long-distance kissing-loop interactions between the 3´-CITE and 5´-proximal hairpins for gRNA and sgRNA translation. Bioassays of CITE mutants have confirmed the importance of the identified 5´-3´ RNA communication for viral infectivity and, moreover, have underlined the strong evolutionary constraints that may operate on genome stretches with both regulatory and coding functions.

  8. Efficient Visual Object and Word Recognition Relies on High Spatial Frequency Coding in the Left Posterior Fusiform Gyrus: Evidence from a Case-Series of Patients with Ventral Occipito-Temporal Cortex Damage

    PubMed Central

    Roberts, Daniel J.; Woollams, Anna M.; Kim, Esther; Beeson, Pelagie M.; Rapcsak, Steven Z.; Lambon Ralph, Matthew A.

    2013-01-01

    Recent visual neuroscience investigations suggest that ventral occipito-temporal cortex is retinotopically organized, with high acuity foveal input projecting primarily to the posterior fusiform gyrus (pFG), making this region crucial for coding high spatial frequency information. Because high spatial frequencies are critical for fine-grained visual discrimination, we hypothesized that damage to the left pFG should have an adverse effect not only on efficient reading, as observed in pure alexia, but also on the processing of complex non-orthographic visual stimuli. Consistent with this hypothesis, we obtained evidence that a large case series (n = 20) of patients with lesions centered on left pFG: 1) Exhibited reduced sensitivity to high spatial frequencies; 2) demonstrated prolonged response latencies both in reading (pure alexia) and object naming; and 3) were especially sensitive to visual complexity and similarity when discriminating between novel visual patterns. These results suggest that the patients' dual reading and non-orthographic recognition impairments have a common underlying mechanism and reflect the loss of high spatial frequency visual information normally coded in the left pFG. PMID:22923086

  9. For-Profit Schools: Large Schools and Schools that Specialize in Healthcare Are More Likely to Rely Heavily on Federal Student Aid. Report to Congressional Committees. GAO-11-4

    ERIC Educational Resources Information Center

    Scott, George A.

    2010-01-01

    In the 2008-2009 school year, about 2,000 for-profit schools received almost $24 billion in grants and loans provided to students under federal student aid programs. In the early 1990s, Congress was concerned that some for-profit schools receiving federal student aid were recruiting students who were not ready for higher education. Many of these…

  10. "You must not rely upon the words that very kind and beautiful girls utter, because in that regard, no offence, they all - lie":venereal diseases as a motive of Fran Gundrum's (1856-1919) work on sexual hygiene.

    PubMed

    Kuhar, Martin; Fatović-Ferenčić, Stella

    2013-01-01

    Until the works of Fran Gundrum, there was no comprehensive analysis of sexuality in Croatia. In this article, we investigate the background of Gundrum's book Sexual Health Care, the first book on sexual hygiene in Croatia. We analyzed the motivational effect venereal diseases had on writing the book, as well as the metaphoric language he used to conceptualize them. Venereal diseases are presented in his work as a consequence of irresponsible sexual behavior, and are interpreted using the analogy of natural state of English political philosopher Thomas Hobbes. All aspects of his suggestions for suppression of venereal diseases were colored by giving priority to social over individual well-being. Tradition and modernity intermix in his work, shaping him as the pioneer of sexual hygiene on our territory in the times when questions about heredity and survival of the nation started to forcefully shape public health policies.

  11. The Downside of Relying on Research Outputs to Assess Business Faculty Performance: Comments from Down Under regarding "Facilitating and Creating Synergies between Teaching and Research: The Role of the Academic Administrator"

    ERIC Educational Resources Information Center

    Chapman, Ross L.

    2012-01-01

    This commentary presents an Australian perspective on Balkin and Mello's "Facilitating and Creating Synergies between Teaching and Research: The Role of the Academic Administrator." It addresses one particularly important aspect of the separation of teaching and research in business schools; namely, the increasing dominance of discipline-based…

  12. Efficient Translation of Pelargonium line pattern virus RNAs Relies on a TED-Like 3´-Translational Enhancer that Communicates with the Corresponding 5´-Region through a Long-Distance RNA-RNA Interaction.

    PubMed

    Blanco-Pérez, Marta; Pérez-Cañamás, Miryam; Ruiz, Leticia; Hernández, Carmen

    2016-01-01

    Cap-independent translational enhancers (CITEs) have been identified at the 3´-terminal regions of distinct plant positive-strand RNA viruses belonging to families Tombusviridae and Luteoviridae. On the bases of their structural and/or functional requirements, at least six classes of CITEs have been defined whose distribution does not correlate with taxonomy. The so-called TED class has been relatively under-studied and its functionality only confirmed in the case of Satellite tobacco necrosis virus, a parasitic subviral agent. The 3´-untranslated region of the monopartite genome of Pelargonium line pattern virus (PLPV), the recommended type member of a tentative new genus (Pelarspovirus) in the family Tombusviridae, was predicted to contain a TED-like CITE. Similar CITEs can be anticipated in some other related viruses though none has been experimentally verified. Here, in the first place, we have performed a reassessment of the structure of the putative PLPV-TED through in silico predictions and in vitro SHAPE analysis with the full-length PLPV genome, which has indicated that the presumed TED element is larger than previously proposed. The extended conformation of the TED is strongly supported by the pattern of natural sequence variation, thus providing comparative structural evidence in support of the structural data obtained by in silico and in vitro approaches. Next, we have obtained experimental evidence demonstrating the in vivo activity of the PLPV-TED in the genomic (g) RNA, and also in the subgenomic (sg) RNA that the virus produces to express 3´-proximal genes. Besides other structural features, the results have highlighted the key role of long-distance kissing-loop interactions between the 3´-CITE and 5´-proximal hairpins for gRNA and sgRNA translation. Bioassays of CITE mutants have confirmed the importance of the identified 5´-3´ RNA communication for viral infectivity and, moreover, have underlined the strong evolutionary constraints that may operate on genome stretches with both regulatory and coding functions. PMID:27043436

  13. Elaboration d'un environnement d'experimentation en simulation incluant un cadre theorique pour l'apprentissage de l'energie des fluides

    NASA Astrophysics Data System (ADS)

    Cervera, Daniel

    Dans cette these, nous presentons la demarche et les diverses etapes qui nous ont conduits a l'elaboration d'un environnement d'experimentation en simulation assistee par ordinateur, incluant un cadre theorique, susceptible d'ameliorer l'apprentissage des concepts relies aux phenomenes qui se produisent dans les systemes technologiques fermes impliquant des fluides (gaz et liquides), tels les systemes hydrauliques et pneumatiques industriels, les systemes de refrigeration, de climatisation et de chauffage. Ces phenomenes ne sont pas directement observables et leur evolution obeit aux interactions complexes qui se produisent a l'interieur des systemes, ce qui leur confere un caractere particulierement abstrait et difficile a comprendre. Notre demarche a consiste a concevoir cet environnement d'apprentissage a partir d'une situation problematique qui se caracterise notamment par la presence de fausses representations conceptuelles chez les etudiants et par la complexite des phenomenes impliques dans les systemes en question. Nous avons conceptualise un environnement d'apprentissage interactif d'inspiration essentiellement constructiviste, base sur l'experimentation et la modelisation didactique et qui permet a l'etudiant d'observer simultanement et en temps reel le comportement des systemes et l'evolution des variables au moyen de graphiques. Aussi, nous avons elabore un cadre theorique pour l'apprentissage de l'energie des fluides, de nature semblable a celui qui existe pour les circuits electriques. Ce cadre theorique explicite les regles qui sous-tendent la maniere dont les fluides se distribuent dans les circuits et permet d'articuler une analyse du comportement des systemes. Nous avons realise deux prototypes de l'environnement d'apprentissage. Le premier a permis de verifier la faisabilite technologique et l'interet didactique des principales orientations du projet. Le deuxieme prototype a ete concu et realise dans le cadre d'une entente de partenariat de type

  14. At the Time of Disclosure: A Manual for Front-Line Community Workers Dealing with Sexual Abuse Disclosures in Aboriginal Communities. Aboriginal Peoples Collection, Technical Series = A l'etape de la divulgation: guide pour les travailleurs communautaires de premiere ligne a qui des actes de violence sexuelle sont divulgues dans les collectivites Autochtones. Collection sur les Autochtones, serie technique.

    ERIC Educational Resources Information Center

    Bopp, Judie; Bopp, Michael

    This manual was developed to assist front-line community workers (including teachers) with issues concerning the disclosure and investigation of sexual abuse allegations in Canadian aboriginal communities. Written in English and French, this document examines the needs of individuals, families, and communities dealing with sexual abuse. Part 1…

  15. L'identite ethnolinguistique et les eleves 16 ans ou plus qui frequentent les ecoles secondaires de langue francaise de l'Ontario. Rapport de recherche (The Ethno-Linguistic Identity of Students Aged 16 Years or Older Attending French-Language Secondary Schools in Ontario. Research Report).

    ERIC Educational Resources Information Center

    Duquette, Georges

    The report, written in French, presents the results of a study on the ethno-linguistic identity of students aged 16 years or older attending French language secondary schools in Ontario. Goals of the questionnaire study included the following: (1) gathering demographics on students about to graduate from high school, regarding their gender,…

  16. Physiotherapy beyond Our Borders: Investigating Ideal Competencies for Canadian Physiotherapists Working in Resource-Poor Countries.

    PubMed

    Cassady, Christina; Meru, Rehana; Chan, Nga Man Carmen; Engelhardt, Julie; Fraser, Michelle; Nixon, Stephanie

    2014-01-01

    Objectif : Analyser ce que les physiothérapeutes du Canada qui ont de l'expérience en santé dans le monde pensent des compétences idéales des physiothérapeutes canadiens œuvrant dans des pays pauvres en ressources. Méthode   : À partir d'une méthodologie d'interprétation qualitative et en nous fondant sur le Profil des compétences essentielles des physiothérapeutes au Canada, 2009 (CEP) comme point de départ de l'étude et de l'analyse, nous avons procédé à des entrevues personnelles et structurées (60 à 90 minutes) auprès de 17 physiothérapeutes du Canada qui ont travaillé dans des pays pauvres en ressources. Des analyses descriptives et thématiques ont été réalisées en collaboration. Résultats : Les sept rôles reliés aux CEP—expert, communicateur, collaborateur, gestionnaire, promoteur, érudit et professionnel—ont tous été considérés comme importants pour les physiothérapeutes canadiens qui travaillent dans des pays pauvres en ressources. Deux rôles, soit ceux de communicateur et de gestionnaire, comportent des compétences supplémentaires que les participants ont jugées importantes. Trois rôles nouveaux—apprenant en santé dans le monde, penseur critique et invité respectueux—ont été créés de façon à décrire d'autres compétences liées à la santé dans le monde jugées cruciales par les participants. Conclusions : Il s'agit de la première étude qui porte sur les compétences dont ont besoin les physiothérapeutes canadiens travaillant dans des pays pauvres en ressources. Outre les rôles reliés aux CEP, d'autres compétences sont recommandées pour travailler dans des pays pauvres en ressources. Ces constatations concordent avec les concepts que véhiculent des publications courantes sur la santé dans le monde et le développement international. Des recherches futures devraient porter sur la pertinence des constatations pour les contextes pauvres en ressources au Canada.

  17. PAHs, PCBs, PBDEs and Pesticides in Cold-Pressed Vegetable Oils.

    PubMed

    Roszko, M; Szterk, A; Szymczyk, K; Waszkiewicz-Robak, B

    2012-03-01

    The aim of this study was to investigate levels of polychlorinated biphenyls (marker and dioxin-like congeners), polycyclic aromatic hydrocarbons (EPA 15 + 1), polybrominated diphenyl ethers (14 predominant congeners) and pesticides (74 compounds) in various cold-pressed vegetable oils. Poppy seed oil, rapeseed oil, sesame seed oil, pumpkinseed oil, hempseed oil, linaire oil, borage oil and evening star oil were investigated. Results of this study revealed that concentrations of PCBs, PBDEs and PAHs were low in majority of the investigated samples. However, high concentrations of organophosphorus insecticides were found. Chlorpyrifos methyl and pirimiphos methyl were the pesticide residues most commonly found in the studied oils. Concentration of 15 + 1 EPA PAHs was within the 17.85-37.16 μg kg(-1) range, concentration of (marker) PCBs varied from 127 to 24,882 pg g(-1), dioxin-like TEQ values were below 0.1 pg TEQ g(-1). Concentration of PBDEs was below LOQ in most cases. PMID:22389518

  18. Etude exploratoire des conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial

    NASA Astrophysics Data System (ADS)

    Robitaille, Jean-Marc

    Il existe peu d'etudes sur les conceptions touchant les domaines de la biologie, notamment sur les conceptions de la circulation sanguine Nous avons observe egalement l'absence de recherche menee aupres d'eleves de l'ordre collegial sur cette question. Nous avons voulu combler une lacune en menant une recherche sur les conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial. Pour mener cette recherche nous nous sommes inspires d'une methode developpee par Treagust (1988). Le premier niveau de formulation didactique etablit l'architecture du systeme et la fonction nutritive de la circulation. Le second niveau de formulation didactique decrit et relie les parametres de la dynamique de la circulation et leur relation: Pression, Debit et Resistance. Le troisieme niveau de formulation didactique s'interesse au controle de la circulation du sang dans un contexte d'homeostasie qui implique la regulation de la pression arterielle. Nous avons construit un questionnaire en nous guidant sur les niveaux de formulation didactique et l'analyse des entrevues menees aupres de dix-huit eleves, representatifs de la population cible. Ce questionnaire fut administre a un echantillon de 2300 eleves disperses dans six colleges de la region de Montreal. Notre echantillon comprend des eleves inscrits a des programmes de l'ordre collegial en Sciences de la nature et en Techniques de la sante et qui n'ont pas suivi le cours sur la circulation sanguine. Notre analyse des reponses des eleves de notre echantillon aux questions sur le premier niveau de formulation didactique revele que la majorite des eleves considerent que le systeme circulatoire relie les organes les uns aux autres dans un circuit en serie. Notre analyse revele egalement que la majorite des eleves estiment que les nutriments sont extraits du sang par les organes selon un processus de selection base sur les besoins determines par la fonction de l'organe. Ces besoins sont differents selon les organes qui ne

  19. A resolution honoring the 29 coal miners who perished in the explosion at the Upper Big Branch Mine in Montcoal, West Virginia, on April 5, 2010, and remembering all those who have lost their lives while mining for the resources on which the United States relies.

    THOMAS, 112th Congress

    Sen. Rockefeller, John D., IV [D-WV

    2011-04-04

    04/05/2011 Resolution agreed to in Senate without amendment and with a preamble by Unanimous Consent. (text: CR S2142-2143) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  20. La prise en charge à long terme de l’asthme chez les enfants inuits et des Premières nations : un outil de transfert du savoir fondé sur les lignes directrices canadiennes pour l’asthme pédiatrique, conçu pour être utilisé par les professionnels de la santé de première ligne qui travaillent dans des communautés isolées

    PubMed Central

    Kovesi, Tom; Giles, Brenda Louise; Pasterkamp, Hans

    L’asthme est un grave problème de santé pour les enfants inuits et des Premières nations. Chez les enfants de moins d’un an, il faut distinguer l’asthme de la bronchiolite virale, anormalement fréquente chez les enfants autochtones du Canada. Chez les enfants de moins de six ans, le diagnostic dépend de la présence de symptômes classiques, de l’absence de caractéristiques atypiques et de la consignation de la réponse au traitement, notamment la réponse rapide et transitoire aux bronchodilatateurs. Chez les enfants plus âgés, il faut, dans la mesure du possible, déterminer la présence d’une obstruction réversible des voies aériennes par spirométrie afin de confirmer le diagnostic, ainsi qu’évaluer et corriger les déclencheurs environnementaux. L’utilisation régulière de corticoïdes en aérosol est la principale mesure à prendre pour maintenir un bon contrôle de l’asthme chez les enfants asthmatiques. Les clients et leur famille devraient recevoir une formation sur l’asthme. Il faut réévaluer régulièrement le contrôle aux visites de suivi dans des centres de santé et rajuster le traitement à la dose la plus basse possible pour le maintien de ce contrôle.

  1. Approche pour les comportements sexuels inappropriés chez des personnes atteintes de démence

    PubMed Central

    Joller, Petra; Gupta, Neeraj; Seitz, Dallas P.; Frank, Christopher; Gibson, Michelle; Gill, Sudeep S.

    2013-01-01

    Résumé Objectif Présenter aux médecins de famille une mise à jour sur l’approche au diagnostic et à la prise en charge des comportements sexuels inappropriés (CSI) chez les personnes atteintes de démence. Sources des données On a fait une recherche dans MEDLINE et EMBASE pour cerner des articles pertinents publiés avant juin 2012. On n’a trouvé aucune étude de niveau I; la plupart des articles fournissaient des données probantes de niveau III. Message principal Les comportements sexuels inappropriés sont fréquents chez les personnes atteintes de démence. Divers facteurs (p. ex., culturels, religieux, perspectives sociétales de la sexualité gériatrique, questions médicolégales) pourraient compliquer l’évaluation de tels comportements et doivent être pris en compte pour permettre une prise en charge appropriée à chaque patient. Il existe des outils pour documenter les CSI. Des interventions créatives non pharmacologiques pour les CSI pourraient être efficaces quand elles sont adaptées à chaque patient. Certaines pharmacothérapies (p. ex., antidépresseurs, antiandrogènes, antipsychotiques et anticonvulsifs) ont été proposées pour les symptômes qui ne répondent pas aux interventions non pharmacologiques. Par ailleurs, les données probantes à l’appui des traitements à l’aide de médicaments sont limitées, les effets secondaires demeurent un aspect important à considérer et il est incertain s’ils devraient être utilisés comme traitement de première ou de deuxième intention. Conclusion Quoiqu’il n’y ait pas d’algorithme de traitements empiriquement établi pour les CSI reliés à la démence, les ouvrages actuels offrent certaines données probantes concernant diverses thérapies pharmacologiques et non pharmacologiques. Des recherches de grande qualité plus approfondies sont nécessaires de toute urgence pour guider les médecins de famille qui prennent en charge des patients qui ont des CSI reliés à la

  2. Inauguration SC

    SciTech Connect

    2006-01-23

    Le DG W.Jentschke ouvre l'inauguration du Syncro Cyclotron (8') et remercie Mons. Michaelis qui prend la parole (30') avant Mons. Wilkinson (53') qui parle du futur de la machine avec présentation des dias.

  3. Mise à jour sur la vaccination contre l’herpès zoster

    PubMed Central

    Shapiro, Marla; Kvern, Brent; Watson, Peter; Guenther, Lyn; McElhaney, Janet; McGeer, Allison

    2011-01-01

    Résumé Objectif Répondre aux questions fréquentes concernant l’utilisation du nouveau vaccin contre l’herpès zoster (HZ). Sources de l’information Les résultats publiés d’études cliniques et d’autres études, les recommandations du Comité consultatif national de l’immunisation du Canada et de l’Advisory Committee on Immunization Practices des États-Unis; des données ont aussi été obtenues dans la monographie du produit approuvée par Santé Canada sur le vaccin. Principal message L’herpès zoster est causé par la réactivation du virus varicelle-zoster; l’algie post-zostérienne (APZ) est sa complication la plus fréquente et la plus grave. L’incidence de l’APZ après un zona est directement reliée à l’âge, notamment 50 % des personnes affectées de plus de 60 ans qui ont des douleurs persistantes non soulagées. Le vaccin à base de virus vivant contre le HZ réduit l’incidence du zona d’environ 50 % et de 2 tiers l’apparition des APZ. De plus, les symptômes sont atténués et de plus courte durée chez les personnes vaccinées. Le vaccin est contre-indiqué chez de nombreux patients immunodéprimés et pourrait ne pas être efficace chez les patients qui prennent des médicaments antiviraux qui agissent contre le virus HZ. Les médecins devraient être au courant des différentes recommandations touchant ces groupes. Conclusion Le vaccin contre le HZ est une mesure de prévention sécuritaire et efficace pour réduire le fardeau global et la gravité du zona chez les adultes plus âgés. Le vaccin semble rentable lorsqu’il est administré à des adultes de 60 ans et plus.

  4. The Endangered Arctic, the Arctic as Resource Frontier: Canadian News Media Narratives of Climate Change and the North.

    PubMed

    Stoddart, Mark C J; Smith, Jillian

    2016-08-01

    The Arctic is one of the most radically altered parts of the world due to climate change, with significant social and cultural impacts as a result. Using discourse network analysis and qualitative textual analysis of articles published in the Globe and Mail and National Post during the period 2006 to 2010, we identify and analyze key frames that interpret the implications of climate change on the Arctic. We examine Canadian national news media coverage to ask: How does the Arctic enter media coverage of climate change? Is there evidence of a climate justice discourse in relation to regional disparities in the risks and harms of climate change between northern and southern Canada? Climate change in the Arctic is often framed through the lens of Canadian national interests, which downplays climate-related social impacts that are already occurring at subnational political and geographical scales. L'Arctique est une des régions du monde la plus radicalement altérée par le changement climatique, menant comme résultat des importants changements sociaux et culturels. En utilisant l'analyse des réseaux de discours ainsi que l'analyse textuelle qualitative des articles publiés dans le Globe and Mail et le National Post de 2006 à 2010, nous identifions and analysons des cadres clés qui servent à interpréter les conséquences du changement climatique dans l'Arctique. Nous examinons la couverture des médias nationaux canadiens pour pouvoir demander : comment est-ce que l'Arctique s'insère dans la couverture médiatique du changement climatique? Est-ce qu'il y a de la preuve d'un discours de la justice climatique en relation des disparités régionales des risques et méfaits du changement climatique entre le Canada du nord et du sud? Le changement climatique dans l'Arctique est souvent encadré à travers le prisme des intérêts nationaux canadiens, ce qui minimise les impacts sociaux reliés au climat qui se produisent actuellement aux échelons sous

  5. The Endangered Arctic, the Arctic as Resource Frontier: Canadian News Media Narratives of Climate Change and the North.

    PubMed

    Stoddart, Mark C J; Smith, Jillian

    2016-08-01

    The Arctic is one of the most radically altered parts of the world due to climate change, with significant social and cultural impacts as a result. Using discourse network analysis and qualitative textual analysis of articles published in the Globe and Mail and National Post during the period 2006 to 2010, we identify and analyze key frames that interpret the implications of climate change on the Arctic. We examine Canadian national news media coverage to ask: How does the Arctic enter media coverage of climate change? Is there evidence of a climate justice discourse in relation to regional disparities in the risks and harms of climate change between northern and southern Canada? Climate change in the Arctic is often framed through the lens of Canadian national interests, which downplays climate-related social impacts that are already occurring at subnational political and geographical scales. L'Arctique est une des régions du monde la plus radicalement altérée par le changement climatique, menant comme résultat des importants changements sociaux et culturels. En utilisant l'analyse des réseaux de discours ainsi que l'analyse textuelle qualitative des articles publiés dans le Globe and Mail et le National Post de 2006 à 2010, nous identifions and analysons des cadres clés qui servent à interpréter les conséquences du changement climatique dans l'Arctique. Nous examinons la couverture des médias nationaux canadiens pour pouvoir demander : comment est-ce que l'Arctique s'insère dans la couverture médiatique du changement climatique? Est-ce qu'il y a de la preuve d'un discours de la justice climatique en relation des disparités régionales des risques et méfaits du changement climatique entre le Canada du nord et du sud? Le changement climatique dans l'Arctique est souvent encadré à travers le prisme des intérêts nationaux canadiens, ce qui minimise les impacts sociaux reliés au climat qui se produisent actuellement aux échelons sous

  6. Mesure du taux de la capture radiative du muon par l'hydrogene liquide

    NASA Astrophysics Data System (ADS)

    Jonkmans, Guy

    À basse énergie, l'interaction faible entre leptons et quarks est décrite par une interaction de la forme courant × courant de type V - A. La présence de l'interaction forte induit des couplages additionnels qui doivent être déterminés expérimentalement. De ceux-ci, le couplage pseudoscalaire induit, gp , est mesuré avec la plus grande incertitude et fait l'objet de la présente recherche. L'hypothèse du Courant Axial Partiellement Conservé (CAPC) et l'usage de la relation de Goldberger-Treiman relie gp au couplage axial ga . Cette relation a été vérifiée traditionnellement par la Capture Ordinaire du Muon (COM) à une valeur fixe du moment de transfert q. La Capture Radiative du Muon (CRM), m- p-->nnmg , est un meilleur outil pour l'étude de gp à cause de sa dépendance variable en q2 qui offre une plus grande sensibilité dans la partie à haute énergie du spectre des photons. Toutefois, le petit rapport d'embranchement (~10-8) de la CRM par rapport à la désintégration du muon a retardé cette mesure jusqu'à ce jour. La théorie et les difficultés expérimentales associées à la détection des photons de CRM sont présentées au deuxième chapitre. On décrit ensuite, au troisième chapitre, les composantes du système de détection. Ce détecteur est un spectromètre à paires de grand angle solide (~3p) et qui permet l'observation des photons par l'analyse des électrons et des positrons de photo-conversion. Ainsi, le bruit de fond important des neutrons de la COM ne constitue pas un problème pour cette mesure. Nous décrivons, au quatrième chapitre, toutes les étapes de l'analyse, nécessaires pour la réduction des multiples bruits de fond. Le cinquième chapitre présente le calcul des efficacités ainsi que l'estimation des erreurs systématiques. Le sixième chapitre démontre comment l'on extrait le rapport d'embranchement pour la CRM ainsi que la valeur ae gp . On insiste sur la dépendance de gp en fonction de la valeur de

  7. Inauguration SC

    ScienceCinema

    None

    2016-07-12

    Le DG W.Jentschke ouvre l'inauguration du Syncro Cyclotron (8') et remercie Mons. Michaelis qui prend la parole (30') avant Mons. Wilkinson (53') qui parle du futur de la machine avec présentation des dias.

  8. European Cosmic Ray Symposium

    SciTech Connect

    2008-04-01

    13me Symposium qui se déroule du 27 au 31 juillet pour la première fois au Cern. Brian Pattison ouvre la cérémonie et donne la parole à Dr.Ugland (qui représente le DG C.Rubbia excusé) et d'autres intervenants

  9. Speech of italian ambassador

    SciTech Connect

    2008-04-09

    L'ambassadeur italien (nom?)fait un discours sur l'aspect de la recherche au Cern, une organisation internationale qui a comme but la connaissance dans sa forme la plus pure et libre d'un intérêt planétaire. Il remet un prix au DG C.Rubbia qui lui remercie en français

  10. Meeting LEP

    SciTech Connect

    2006-05-23

    Le DG J.Adams fait l'introduction et présente les deux autres orateurs. Pierre Darriulat qui fait un doscours sur la physique à l'occasion du LEP, Wolfgang Schnell, qui parle du projet de la machine LEP et le DG lui-même contribue avec quelques réflexions. Présentation des dias

  11. In vitro characterization of echinomycin biosynthesis: formation and hydroxylation of L-tryptophanyl-S-enzyme and oxidation of (2S,3S) β-hydroxytryptophan.

    PubMed

    Zhang, Chen; Kong, Lingxin; Liu, Qian; Lei, Xuan; Zhu, Tao; Yin, Jun; Lin, Birun; Deng, Zixin; You, Delin

    2013-01-01

    Quinoxaline-2-carboxylic acid (QXC) and 3-hydroxyquinaldic acid (HQA) feature in quinomycin family and confer anticancer activity. In light of the significant potency against cancer, the biosynthetic gene clusters have been reported from many different Streptomyces strains, and the biosynthetic pathway were proposed mainly based on the in vivo feeding experiment with isotope labeled putative intermediates. Herein we report another gene cluster from Streptomyces griseovariabilis subsp. bandungensis subsp. nov responsible for the biosynthesis of echinomycin (a member of quinomycin family, also named quinomycin A) and presented in vitro evidence to corroborate the previous hypothesis on QXC biosynthesis, showing that only with the assistance of a MbtH-like protein Qui5, did the didomain NRPS protein (Qui18) perform the loading of a L-tryptophan onto its own PCP domain. Particularly, it was found that Qui5 and Qui18 subunits form a functional tetramer through size exclusion chromatography. The subsequent hydroxylation on β-carbon of the loaded L-tryptophan proved in vitro to be completed by cytochrome P450-dependent hydroxylase Qui15. Importantly, only the Qui18 loaded L-tryptophan can be hydroxylated by Qui15 and the enzyme was inactive on free L-tryptophan. Additionally, the chemically synthesized (2S,3S) β-hydroxytryptophan was detected to be converted by the tryptophan 2,3-dioxygenase Qui17 through LC-MS, which enriched our previous knowledge that tryptophan 2,3-dioxygenase nearly exclusively acted on L-tryptophan and 6-fluoro-tryptophan.

  12. Le syndrome d’alcoolisme foetal

    PubMed Central

    2002-01-01

    L’alcool est un tératogène physique et comportemental. Le syndrome d’alcoolisme foetal (SAF) est un trouble courant mais encore sous-diagnostiqué découlant de la consommation d’alcool par la mère pendant la grossesse. Bien qu’il puisse être prévenu, le SAF est également invalidant. Même si le SAF est présent dans tous les groupes socioéconomiques du Canada, sa prévalence est élevée dans certaines communautés inuites et des Premières nations du Canada. Le présent énoncé porte sur la prévention, le diagnostic, le dépistage précoce et la prise en charge du SAF par les professionnels de la santé. La prévention du SAF doit s’effectuer à deux échelons. La prévention primaire consiste à éliminer le SAF par une formation en classe ou dans la collectivité et à inciter les femmes à éviter de consommer de l’alcool avant la conception et pendant la grossesse. La prévention secondaire consiste à repérer les femmes qui boivent pendant leur grossesse et à réduire leur consommation. Le présent énoncé décrit plusieurs stratégies de dépistage, dont la stratégie T-ACE (tolérance-agacement, réduction, éveil). Les dispensateurs de soins devraient recommander l’abstinence dès la première visite prénatale. Un envoi rapide en consultation en vue de traiter l’alcoolisme est recommandé pour les femmes enceintes incapables d’arrêter de boire. Le présent énoncé décrit le diagnostic de SAF, de SAF partiel ou atypique, d’anomalies congénitales et de troubles neurodéveloppementaux reliés à l’alcool. En cas d’exposition à l’alcool in utero, un diagnostic de SAF devrait être envisagé en présence d’un retard de croissance courant ou antérieur, de certaines anomalies faciales touchant la lèvre supérieure et les yeux et d’anomalies neurodéveloppementales. Ces caractéristiques sont mieux quantifiées au moyen d’une méthode diagnostique à quatre chiffres. Des stratégies de dépistage précoce des

  13. Étude par spectroscopie d'admittance et MEB de la dégradation électrique des couches minces de CuAlS{2} non dopé déposées sous vide

    NASA Astrophysics Data System (ADS)

    Helali, N.; Bouricha, B.; Rezig, B.

    1998-07-01

    We have accelerated the ageing of CuAlS2 by the application of a static electrical field for different degradation times. We have investigated the admittance spectroscopy and the scanning electron microscopy to follow and understand the (mass-charge) coupled transport processes produced in the volume and on the surface of these films. The electrical constraint induces, after an incubation phase, an activated decrease of the resistance, followed by a susbstantial increase correlated to the formation of an open circuit. This degradation occurs more rapidly for the films having initially a lower resistance, due to the thermal dissipation which increases considerably the temperature to about 140 °C. Admittance spectra reveal, at low frequencies, a capacitive loop related to the formation of a charge space induced by copper diffusion. Such migration develop induces the formation of copper arborescences, spreading from the cathode towards the anode. The effect of these structures on the properties of the degraded films is discussed in relation to electromigration and associated processes (whiskers, fracture, healing, bridge-building, ...). Also, we have noticed their similarity with fractal phenomena such as electrodeposition and dielectric breakdown. Nous avons accéléré le vieillissement des couches minces de CuAlS2 par l'application d'un champ électrique statique pendant des durées variables. Nous avons fait appel à la spectroscopie d'admittance et la microscopie électronique à balayage, pour suivre et comprendre les processus de transport couplé (masse- charge) qui se produisent en volume et en surface de ces couches. L'effet de la contrainte électrique s'est traduit, après une phase d'incubation, par une décroissance activée de la résistance, suivie d'une phase d'emballement reliée à la formation d'un circuit ouvert. Cette fracturation se manifeste plus rapidement pour les couches ayant initialement une faible résistance, suite à l'effet de la

  14. De l'importance des orbites periodiques: Detection et applications

    NASA Astrophysics Data System (ADS)

    Doyon, Bernard

    L'ensemble des Orbites Periodiques Instables (OPIs) d'un systeme chaotique est intimement relie a ses proprietes dynamiques. A partir de l'ensemble (en principe infini) d'OPIs cachees dans l'espace des phases, on peut obtenir des quantites dynamiques importantes telles les exposants de Lyapunov, la mesure invariante, l'entropie topologique et la dimension fractale. En chaos quantique (i.e. l'etude de systemes quantiques qui ont un equivalent chaotique dans la limite classique), ces memes OPIs permettent de faire le pont entre le comportement classique et quantique de systemes non-integrables. La localisation de ces cycles fondamentaux est un probleme complexe. Cette these aborde dans un premier temps le probleme de la detection des OPIs dans les systemes chaotiques. Une etude comparative de deux algorithmes recents est presentee. Nous approfondissons ces deux methodes afin de les utiliser sur differents systemes dont des flots continus dissipatifs et conservatifs. Une analyse du taux de convergence des algorithmes est aussi realisee afin de degager les forces et les limites de ces schemes numeriques. Les methodes de detection que nous utilisons reposent sur une transformation particuliere de la dynamique initiale. Cette astuce nous a inspire une methode alternative pour cibler et stabiliser une orbite periodique quelconque dans un systeme chaotique. Le ciblage est en general combine aux methodes de controle pour stabiliser rapidement un cycle donne. En general, il faut connaitre la position et la stabilite du cycle en question. La nouvelle methode de ciblage que nous presentons ne demande pas de connaitre a priori la position et la stabilite des orbites periodiques. Elle pourrait etre un outil complementaire aux methodes de ciblage et de controle actuelles.

  15. Le syndrome d’alcoolisme foetal

    PubMed Central

    2002-01-01

    L’alcool est un tératogène physique et comportemental. Le syndrome d’alcoolisme foetal (SAF) est un trouble courant mais encore sous-diagnostiqué découlant de la consommation d’alcool par la mère pendant la grossesse. Bien qu’il puisse être prévenu, le SAF est également invalidant. Même si le SAF est présent dans tous les groupes socioéconomiques du Canada, sa prévalence est élevée dans certaines communautés inuites et des Premières nations du Canada. Le présent énoncé porte sur la prévention, le diagnostic, le dépistage précoce et la prise en charge du SAF par les professionnels de la santé. La prévention du SAF doit s’effectuer à deux échelons. La prévention primaire consiste à éliminer le SAF par une formation en classe ou dans la collectivité et à inciter les femmes à éviter de consommer de l’alcool avant la conception et pendant la grossesse. La prévention secondaire consiste à repérer les femmes qui boivent pendant leur grossesse et à réduire leur consommation. Le présent énoncé décrit plusieurs stratégies de dépistage, dont la stratégie T-ACE (tolérance-agacement, réduction, éveil). Les dispensateurs de soins devraient recommander l’abstinence dès la première visite prénatale. Un envoi rapide en consultation en vue de traiter l’alcoolisme est recommandé pour les femmes enceintes incapables d’arrêter de boire. Le présent énoncé décrit le diagnostic de SAF, de SAF partiel ou atypique, d’anomalies congénitales et de troubles neurodéveloppementaux reliés à l’alcool. En cas d’exposition à l’alcool in utero, un diagnostic de SAF devrait être envisagé en présence d’un retard de croissance courant ou antérieur, de certaines anomalies faciales touchant la lèvre supérieure et les yeux et d’anomalies neurodéveloppementales. Ces caractéristiques sont mieux quantifiées au moyen d’une méthode diagnostique à quatre chiffres. Des stratégies de dépistage précoce des

  16. The lathyrus toxin, {beta}-N-oxalyl-L-{alpha},{beta}-diaminopropionic acid (ODAP), and homocysteic acid sensitize CA1 pyramidal neurons to cystine and L-2-amino-6-phosphonohexanoic acid

    SciTech Connect

    Chase, L.A. . E-mail: chase@hope.edu; Peterson, N.L. . E-mail: nlpeterson@noctrl.edu; Koerner, J.F. . E-mail: koern003@umn.edu

    2007-02-15

    A brief exposure of hippocampal slices to L-quisqualic acid (QUIS) sensitizes CA1 pyramidal neurons 30- to 250-fold to depolarization by certain excitatory amino acids analogues, e.g., L-2-amino-6-phosphonohexanoic acid (L-AP6), and by the endogenous compound, L-cystine. This phenomenon has been termed QUIS sensitization. A mechanism similar to that previously described for QUIS neurotoxicity has been proposed to describe QUIS sensitization. Specifically, QUIS has been shown to be sequestered into GABAergic interneurons by the System x{sub c} {sup -} and subsequently released by heteroexchange with cystine or L-AP6, resulting in activation of non-NMDA receptors. We now report two additional neurotoxins, the Lathyrus excitotoxin, {beta}-N-oxalyl-L-{alpha},{beta}-diaminopropionic acid (ODAP), and the endogenous compound, L-homocysteic acid (HCA), sensitize CA1 hippocampal neurons > 50-fold to L-AP6 and > 10-fold to cystine in a manner similar to QUIS. While the cystine- or L-AP6-mediated depolarization can be inhibited by the non-NMDA receptor antagonist CNQX in ODAP- or QUIS-sensitized slices, the NMDA antagonist D-AP5 inhibits depolarization by cystine or L-AP6 in HCA-sensitized slices. Thus, HCA is the first identified NMDA agonist that induces phosphonate or cystine sensitization. Like QUIS sensitization, the sensitization evoked by either ODAP or HCA can be reversed by a subsequent exposure to 2 mM {alpha}-aminoadipic acid. Finally, we have demonstrated that there is a correlation between the potency of inducers for triggering phosphonate or cystine sensitivity and their affinities for System x{sub c} {sup -} and either the non-NMDA or NMDA receptor. Thus, the results of this study support our previous model of QUIS sensitization and have important implications for the mechanisms of neurotoxicity, neurolathyrism and hyperhomocystinemia.

  17. Hans Bethe : Des etoiles a la bombe

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1996-06-01

    Il comprit le premier comment brillent les etoiles. Il fut aussi de cette poignee de scientifiques qui, dans le secret de Los Alamos, mirent au point la tristement celebre bombe atomique. Hans Bethe est l'un des derniers geants qui auront marque la physique de ce siecle d'une empreinte indelebile. C'est dans le bureau 01 du prestigieux laboratoire Kellog de l'institut Caltech qu'il a bien voulu retracer pour nous son impressionnante carriere, et revenir sur les motivations qui ont guide ses pas.

  18. Comparison of quisqualic and ibotenic acid nucleus basalis magnocellularis lesions on water-maze and passive avoidance performance.

    PubMed

    Riekkinen, M; Riekkinen, P; Riekkinen, P

    1991-07-01

    The present study compares water-maze (WM) (reference and working memory) and passive avoidance (PA) (acquisition and retention) deficits induced by ibotenic (ibo) and quisqualic (quis) acid nucleus basalis magnocellularis (NBM) lesions. Ibo lesions produced a large subcortical cell loss and a decrease in frontal cortex (FR) choline acetyltransferase (ChAT) activity. Ibo lesions impaired WM acquisition and PA acquisition and retention performance. Quis NBM lesions were restricted to the ventromedial pallidum, but ChAT activity was decreased in FR. Quis NBM lesions impaired PA acquisition and retention, but had no effect on the reference or working memory WM performance.

  19. Small Solid Rocket Motor Test

    NASA Video Gallery

    It was three-two-one to brilliant fire as NASA's Marshall Space Flight Center tested a small solid rocket motor designed to mimic NASA's Space Launch System booster. The Mar. 14 test provides a qui...

  20. Meeting LEP

    ScienceCinema

    None

    2016-07-12

    Le DG J.Adams fait l'introduction et présente les deux autres orateurs. Pierre Darriulat qui fait un doscours sur la physique à l'occasion du LEP, Wolfgang Schnell, qui parle du projet de la machine LEP et le DG lui-même contribue avec quelques réflexions. Présentation des dias

  1. European Cosmic Ray Symposium

    ScienceCinema

    None

    2016-07-12

    13me Symposium qui se déroule du 27 au 31 juillet pour la première fois au Cern. Brian Pattison ouvre la cérémonie et donne la parole à Dr.Ugland (qui représente le DG C.Rubbia excusé) et d'autres intervenants

  2. History of Cern

    ScienceCinema

    None

    2016-07-12

    Cérémonie à l'occasion de l'apparition du premier volume du livre sur l'histoire du Cern, avec plusieurs personnes présentes qui jouaient un rôle important dans cette organisation européenne couronnée de succès grâce à l'esprit des membres fondateurs qui est et restera essentiel

  3. Speech of italian ambassador

    ScienceCinema

    None

    2016-07-12

    L'ambassadeur italien (nom?)fait un discours sur l'aspect de la recherche au Cern, une organisation internationale qui a comme but la connaissance dans sa forme la plus pure et libre d'un intérêt planétaire. Il remet un prix au DG C.Rubbia qui lui remercie en français

  4. Une cause rare de plexopathie brachiale: une metastase d'un cancer du sein

    PubMed Central

    Maâroufi, Mustapha; Kamaoui, Imane; Boubbou, Meriem; Sqalli, Nadia; Tizniti, Siham

    2014-01-01

    Nous rapportons le cas d'une patiente de 50 ans ayant une histoire de cancer du sein et qui accuse une symptomatologie d'atteinte du plexus brachial. L'IRM montre une masse qui envahie le plexus brachial compatible avec une métastase. L'IRM est très utile pour le diagnostic et l'orientation thérapeutique des plexopathies brachiales chez les femmes présentant un cancer du sein PMID:25360196

  5. In Vitro Characterization of Echinomycin Biosynthesis: Formation and Hydroxylation of L-Tryptophanyl-S-Enzyme and Oxidation of (2S,3S) β-Hydroxytryptophan

    PubMed Central

    Liu, Qian; Lei, Xuan; Zhu, Tao; Yin, Jun; Lin, Birun; Deng, Zixin; You, Delin

    2013-01-01

    Quinoxaline-2-carboxylic acid (QXC) and 3-hydroxyquinaldic acid (HQA) feature in quinomycin family and confer anticancer activity. In light of the significant potency against cancer, the biosynthetic gene clusters have been reported from many different Streptomyces strains, and the biosynthetic pathway were proposed mainly based on the in vivo feeding experiment with isotope labeled putative intermediates. Herein we report another gene cluster from Streptomyces griseovariabilis subsp. bandungensis subsp. nov responsible for the biosynthesis of echinomycin (a member of quinomycin family, also named quinomycin A) and presented in vitro evidence to corroborate the previous hypothesis on QXC biosynthesis, showing that only with the assistance of a MbtH-like protein Qui5, did the didomain NRPS protein (Qui18) perform the loading of a L-tryptophan onto its own PCP domain. Particularly, it was found that Qui5 and Qui18 subunits form a functional tetramer through size exclusion chromatography. The subsequent hydroxylation on β-carbon of the loaded L-tryptophan proved in vitro to be completed by cytochrome P450-dependent hydroxylase Qui15. Importantly, only the Qui18 loaded L-tryptophan can be hydroxylated by Qui15 and the enzyme was inactive on free L-tryptophan. Additionally, the chemically synthesized (2S,3S) β-hydroxytryptophan was detected to be converted by the tryptophan 2,3-dioxygenase Qui17 through LC-MS, which enriched our previous knowledge that tryptophan 2,3-dioxygenase nearly exclusively acted on L-tryptophan and 6-fluoro-tryptophan. PMID:23437232

  6. Prise en charge en soins primaires des troubles liés à l’usage d’alcool et de la consommation à risque

    PubMed Central

    Spithoff, Sheryl; Kahan, Meldon

    2015-01-01

    Résumé Objectif Fournir aux médecins de soins primaires de l’information et des conseils fondés sur des données probantes sur le dépistage et l’évaluation de la consommation d’alcool à risque et des troubles liés à l’usage d’alcool (TUA). Sources des données Nous avons effectué une recherche documentaire non systématique en utilisant des expressions de recherche portant sur les soins primaires, les TUA, la dépendance à l’alcool, l’abus d’alcool, l’usage abusif d’alcool, la consommation d’alcool néfaste pour la santé, ainsi que le dépistage, la détermination et l’évaluation dans le contexte des soins primaires. Principaux messages Les médecins de famille devraient faire passer un test validé de dépistage de l’abus d’alcool à tous les patients, au moins une fois par année. Dépister les patients qui se présentent avec des problèmes médicaux ou psychosociaux pouvant être reliés à l’usage d’alcool. Déterminer si les patients qui obtiennent des résultats positifs lors du dépistage sont des consommateurs d’alcool à risque ou s’ils ont des TUA. Si les patients ont des TUA, déterminer si les troubles sont légers, modérés ou sévères en utilisant les critères de la 5e édition du Manuel diagnostique et statistique des troubles mentaux. Communiquer le diagnostic aux patients et leur offrir de l’aide. Effectuer une évaluation plus approfondie des patients ayant des TUA. Procéder à un dépistage de la consommation d’autres substances, des troubles concomitants et des traumatismes. Déterminer s’il est nécessaire de rapporter le cas aux services de protection de l’enfance ou au ministère des Transports. Déterminer les besoins en matière de prise en charge médicale du sevrage alcoolique. Effectuer un bref examen physique et prescrire l’exécution de tests de laboratoire pour évaluer la formule sanguine complète et les taux de transaminases hépatiques, comprenant les

  7. Approche au diagnostic de la maladie cœliaque chez les patients ayant une faible densité minérale osseuse ou des fractures de fragilité

    PubMed Central

    Rios, Lorena P.; Khan, Aliya; Sultan, Muhammad; McAssey, Karen; Fouda, Mona A.; Armstrong, David

    2013-01-01

    Résumé Objectif Présenter aux cliniciens une mise à jour sur le diagnostic de la maladie cœliaque (MC), ainsi que des recommandations sur les indications de procéder au dépistage de la MC chez les patients présentant une faible densité minérale osseuse (DMO) ou des fractures de fragilité. Qualité des données Un groupe de travail multidisciplinaire a élaboré des questions cliniquement pertinentes relativement au diagnostic de la MC servant de fondement à une recherche documentaire dans les bases de données MEDLINE, EMBASE et CENTRAL (de janvier 2000 à janvier 2009) à l’aide des mots clés en anglais celiac disease, osteoporosis, osteopenia, low bone mass et fracture. Les ouvrages scientifiques existants comportent des études de niveaux I et II. Message principal La prévalence estimée de la MC asymptomatique est de 2 % à 3 % chez les personnes qui ont une faible DMO. Par ailleurs, un dépistage ciblé est recommandé pour les patients qui ont des T-scores de −1,0 ou moins à la colonne vertébrale ou aux hanches ou des antécédents de fractures de fragilité associées à des symptômes ou à des problèmes reliés à la MC, des antécédents familiaux de MC ou de bas niveaux de calcium urinaire, une insuffisance en vitamine D et des niveaux à la hausse d’hormones parathyroïdiennes en dépit d’un apport suffisant en calcium et en vitamine D. Le dépistage de la MC devrait se faire pendant que le sujet consomme un régime alimentaire contenant du gluten. On procède au dépistage initial par le dosage d’immunoglobuline (Ig) A antitransglutaminase en utilisant la transglutaminase tissulaire humaine recombinante ou une autre transglutaminase tissulaire, en association avec l’immunofluorescence des IgA anti-endomysium. Une biopsie du duodénum est nécessaire pour confirmer le diagnostic de la MC. Le typage des antigènes des leucocytes humains peut aider à confirmer ou à exclure le diagnostic de la MC dans les cas où la s

  8. Blocage de Coulomb dans une boite quantique laterale contenant un faible nombre d'electrons

    NASA Astrophysics Data System (ADS)

    Gould, Charles

    Dans ce travail on utilise une nouvelle geometrie pour augmenter le controle sur le nombre d'electrons contenus dans une boite quantique laterale, et ainsi atteindre un regime de petit nombre d'electrons. Ces echantillons permettent une etude du blocage de Coulomb quand les electrons sont injectes a partir d'un gaz electronique a deux dimensions (2DEG). Les mesures a faible champ magnetique demontrent la grande flexibilite des echantillons et montrent que l'on peut faire varier le nombre d'electrons dans une boite quantique a partir de plus de 40 electrons jusqu'a un seul electron, ce qui est assez courant dans les boites quantiques verticales, mais ce qui n'avait jamais ete reussi dans une boite quantique laterale. Nos resultats montrent egalement que dans les boites quantiques laterales il est possible de determiner le spin du niveau qui participe au transport a l'aide du phenomene de blocage de spin. De plus, dans certaines circonstances il est meme possible de determiner le spin total de la boite quantique, ce qui peut avoir des applications pratiques dans des domaines tels l'informatique quantique. Les mesures dans le regime de renversement de spin a un champ magnetique plus eleve montrent l'importance des correlations electrons---electrons dans ces boites quantiques, qui menent a des depolarisations et a des structures de spins qui ont un effet sur le transport. En particulier, ces correlations menent a l'existence de niveaux excites de basse energie qui causent une dependance anormale de l'amplitude des pics de blocage de Coulomb en fonction de la temperature. Nos experiences demontrent egalement la possibilite d'utiliser ces boites quantiques comme sondes pour etudier les proprietes du bord d'un 2DEG. Une voie de recherche a etre exploree.

  9. NMR and molecular modeling: application to wine ageing

    NASA Astrophysics Data System (ADS)

    Saucier, C.; Pianet, I.; Laguerre, M.; Glories, Y.

    1998-02-01

    Red wine contains polyphenols called tannins which are very important for its taste and longevity. These polymers consist in repeating units of catechin and its epimer epicatechin. During ageing, slow condensation reactions take place which lead to new chemical structures. Among the possible reactions, we have focused our attention on acetaldehyde cross-linking. Catechin was used as a model for the production of polymers with acetaldehyde. Two reaction product fractions have been isolated by liquid chromatography. Mass measurement indicated that these fractions contain dimers. NMR (1D and 2D) and molecular modelling were then used to study the structure and conformations of these products. The first product consist in a pure dimer with the two catechin moieties connected with an ethyl bridge on the carbon 6 and 8. The second fraction was a mixture of two dimers (50/50). NMR measurements showed that it could be two symmetrical dimers involving the same carbon for each catechin moiety (6 or8). Le vin rouge contient des polyphénols appelés tanins qui sont très importants pour son goût et sa longévité. Il s'agit principalement de polymères de catéchine et d'épicatéchine. Durant le vieillissement du vin, des réactions de condensation interviennent lentement et conduisent à de nouvelles structures. Parmi les réactions possibles, nous avons plus spécialement étudié la polymérisation par pontage avec l'éthanal. La catéchine a été utilisée comme modèle de tannin et mise en présence d'éthanal en milieu acide proche du vin. Deux fractions de produits de réaction ont été isolées par chromatographie liquide. La spectrométrie de masse a révélé la présence de dimères. La RMN (1D et 2D) et la modélisation moléculaire ont ensuite été utilisées pour déterminer la structure et la conformation de ces produits. La première fraction a été identifiée comme étant un dimère de deux unités catéchines reliées par un pont éthyle par leur

  10. Self-Employment among Same-Sex and Opposite-Sex Couples in Canada.

    PubMed

    Waite, Sean; Denier, Nicole

    2016-05-01

    This study presents novel evidence on the relationship between sexual orientation and self-employment. Using data from the 2001 and 2006 Census of Canada and the 2011 Canadian National Household Survey, we explore the propensity for self-employment among same- and opposite-sex couples. We examine the demographic, human capital, and family characteristics of coupled gay men and lesbians relative to their coupled heterosexual counterparts to offer potential mechanisms generating differences in rates of self-employment. Our analysis further considers occupational variability in the likelihood of self-employment. We find that gay men are less likely and lesbians more likely than heterosexuals to be self-employed; however, there is significant variation across occupations. Gay men are more likely to be self-employed in arts and culture, sales and service, and natural and applied sciences, but less likely in business, finance, and health-related occupations. Lesbians are much more likely to be self-employed in health-related occupations, natural and applied sciences, and arts and culture. Marriage and having children are significant predictors of self-employment for coupled heterosexual women but not lesbians. Cette étude présente des évidences empiriques concernant la relation entre l'orientation sexuelle et le travail indépendant. Utilisant des données provenant du Recensement du Canada de 2001 et de 2006, ainsi que l'Enquête nationale auprès des ménages (ENM) de 2011, nous explorons la tendance du travail indépendant parmi les couples de même sexe et ceux de sexe opposé. Ainsi, nous examinons les caractéristiques démographiques, du capital humain et familiales des couples gais et lesbiens par rapport à leurs homologues hétérosexuels, afin de démontrer une corrélation entre l'orientation sexuelle et la probabilité d'être travailleur indépendant - une causation qui nous semble évident et que nous analysons plus en profondeur. Nous concluons d

  11. Comparison of brain mechanisms underlying the processing of Chinese characters and pseudo-characters: an event-related potential study.

    PubMed

    Wang, Ting; Li, Hong; Zhang, Qinglin; Tu, Shen; Yu, Caiyun; Qiu, Jiang

    2010-04-01

    basis of orthographic, phonological and perceptual-semantic processing. La plupart des caractères chinois sont composés d'un radical sémantique à gauche et d'un radical phonétique à droite. Le radical sémantique peut fournir de l'information sémantique et le radical phonétique peut fournir de l'information concernant la prononciation du caractère entier. Les pseudo-caractères consistaient en différentes parties sous-lexicales des caractères chinois réels et, conséquemment, ils avaient aussi un radical sémantique et un radical phonétique. Mais ils ne pouvaient pas être lisibles et ils n'ont actuellement aucun sens. Afin d'étudier les patrons d'activation spatiotemporels corticaux sous-jacents aux traitements orthographique, phonologique et sémantique des caractères chinois, nous avons utilisé des Potentiels cérébraux reliés aux événements (PRE) pour explorer le traitement des caractères et des pseudo-caractères chinois auprès de 14 collégiens chinois visionnant les caractères passivement. Les résultats ont montré qu'à la fois les caractères et les pseudo-caractères chinois provoquaient un potentiel négatif évident atteignant un sommet autour de 120 ms (N120), ce qui apparaissait refléter la distinction et l'évaluation orthographiques initiales. Puis, les pseudo-caractères ont provoqué une déviation PRE plus positive (P220) que les caractères chinois entre 200 et 250 ms après l'apparition des stimuli. Ceci était similaire au PR (Potentiel de reconnaissance) et pouvait refléter les processus d'intégration des traitements phonologique et sémantique sur la base de l'information orthographique initiale. L'analyse dipôle de source de la différence de courbe (pseudo-caractères moins caractères) a indiqué qu'un générateur localisé dans la jonction temporo-occipitale gauche contribuait à cet effet, ce qui était possiblement relié à l'intégration de l'information phonologique et perceptuelle-sémantique. Entre 350 et

  12. Le stéréorestituteur Kelsh

    USGS Publications Warehouse

    Kelsh, H.T.

    1949-01-01

    Le ste??re??orestituteur Kelsh est un appareil de restitution a?? double projection base?? sur le principe des anaglyphes, comme le Multiplex par exemple, mais il a une plus grande pre??cision que ce dernier, vu que les ne??gatifs sont utilise??s directement pour la restitution, sans que l'on soit oblige?? de les re??duire au pre??alable. Une telle solution devient possible lorsque l'e??chelle de l'image plastique (mode??le) est au moins 7 fois plus grande que celle des cliche??s. L'appareil comprend un support reposant par 4 pieds sur la table a?? dessin. Sa partie supe??rieure porte, par l'interme??diaire de trois vis calantes, un cadre dans lequel les deux chambres de projection sont suspendues. Des leviers de commande, agissant sur les chambres, permettent d'introduire la base, le de??versement et les inclinaisons transversale et longitudinale. Les cliche??s conjugue??s ou des diapositifs sont directement place??s dans les chambres de projection munies d'objectifs. En projetant les deux cliche??s au moyen de couleurs comple??mentaires, l'observateur - muni de lunettes a?? verres colore??s (couleurs comple??mentaires) - observe l'image plastique audessus de la table a?? dessin, l'orientation relative des chambres ayant e??te?? e??tablie au pre??alable. Pour le report des points de l'image plastique sur la minute, l'ope??rateur dispose d'une tablette amovible a?? marque-repe??re lumineuse qu'il de??place a?? la main et dont la hauteur au-dessus de la table a?? dessin peut e??tre commande??e par une molette. Pour e??tablir l'orientation absolue de l'image plastique, il suffit d'incliner convenablement le cadre de suspension a?? l'aide des vis calantes, l'orientation relative n'e??tant pas de??truite par cette ope??ration. Les deux cliche??s sont e??claire??s par des projecteurs munis d'une suspension a?? la cardan et relie??s a?? la tablette de restitution par des tiges te??lescopiques. Moyennant ce dispositif, l'e??clairage est concentre?? sur deux petites re

  13. Une spondylodiscite tuberculeuse chez une transplantée rénale compliquée d’une mycose systémique

    PubMed Central

    Haddiya, Intissar; El Housni, Siham; El Harraqui, Ryme; Rhou, Hakima; Benamar, Loubna; Eziatouni, Fatima; Ouzeddoun, Naima; Bayahia, Rabia

    2014-01-01

    En transplantation, les complications infectieuses sont fréquentes et de diagnostic souvent délicat. Elles peuvent coexister chez le transplanté rénal rendant leur diagnostic encore plus difficile. Le but de ce cas clinique est de discuter les difficultés diagnostiques et de surveillance de deux types de pathologies assez fréquentes chez le transplanté rénal, qui sont la tuberculose et la mycose, à travers l’observation clinique d’une patiente de 24 ans transplantée rénale qui présente une spondylodiscite tuberculeuse et qui développe secondairement une septicémie à Candida non albicans à point de départ urinaire dont le seul point d’appel est la fièvre post opératoire. PMID:25667684

  14. Les considérations éthiques relatives à la désadoption d'aspects inefficaces ou nuisibles des soins de santé.

    PubMed

    Niven, Daniel J; Leigh, Jeanna Parsons; Stelfox, Henry T

    2016-09-01

    La désadoption désigne l'abandon d'une pratique médicale ou d'un service de santé inefficace ou nuisible après une période d'adoption. Tandis que les dépenses croissantes en matière de santé menacent de paralyser les sociétés qui les financent, le fait de faciliter la désadoption peut faire partie intégrante de systèmes de santé durables qui prodiguent des soins de qualité. Le présent article explore des enjeux éthiques qui se rapportent à la désadoption, y compris les principes sous-jacents de bénéficience, de non-maléficience, de justice et d'autonomie. PMID:27576859

  15. Insuffisance rénale aigüe: présentation rare d’une maladie d’Addison

    PubMed Central

    Salhi, Houda

    2016-01-01

    La maladie d’Addison est une pathologie rare, qui se manifeste fréquemment par des signes cliniques non spécifiques. Ce qui peut causer un retard diagnostic et thérapeutique. Cette maladie peut se présenter comme un tableau d’insuffisance rénale aigue. Nous rapportons le cas d’un patient présentant une maladie d’Addison qui a été pris en charge initialement comme une insuffisance rénale aigue secondaire à un myélome multiple et dont le diagnostic a été redressé par la suite. Le patient s’est spectaculairement amélioré après mis en place de traitement par réhydratation par voie intraveineuse; hydrocortisone injectable.

  16. Defining the criteria for identifying constitutional epimutations.

    PubMed

    Sloane, Mathew A; Ward, Robyn L; Hesson, Luke B

    2016-01-01

    In the January 2016 issue of Clinical Epigenetics, Quiñonez-Silva et al. (Clin Epigenetics 8:1, 2016) described a possible constitutional epimutation of the RB1 gene as a cause of hereditary predisposition to retinoblastoma. The term constitutional epimutation describes an epigenetic aberration in normal tissues that predisposes to disease. The data presented by Quiñonez-Silva et al. are interesting, but further analysis is required to demonstrate a constitutional epimutation in this family. Here, we define the criteria and describe the experimental approach necessary to identify an epigenetic aberration as a constitutional epimutation. PMID:27096027

  17. L'Aventure du LHC

    SciTech Connect

    2010-06-11

    Cette présentation s’adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l’engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  18. Social orientations and adolescent health behaviours in Hungary.

    PubMed

    Piko, Bettina F; Skultéti, Dóra; Luszczynska, Aleksandra; Gibbons, Frederick X

    2010-02-01

    ôle que ces orientations sociales peuvent jouer dans les comportements de santé (à la fois néfastes et bénéfiques). Les données ont été recueillies auprès d'étudiants collégiaux (N = 548; âgés de 14 à 20 ans; 39.9% masculins) dans deux comtés du sud de la Hongrie. Les questionnaires auto-administrés contenaient des items portant sur les aspects sociodémographiques (tels que l'âge, le sexe, la scolarité des parents et le niveau économique), la performance scolaire, les comportements de santé, la compétitivité et la comparaison sociale. Des analyses de régression multiple suggèrent que ceux qui ont obtenu des scores supérieurs de compétitivité consommaient plus de substances, un patron qui n'était pas présent pour les comportements de santé bénéfiques. La comparaison sociale, cependant, était associée à de faibles niveaux de consommation de substances. De plus, en relation avec les comportements de santé néfastes, à la fois la compétitivité et la comparaison sociale interagissaient avec le sexe; les deux variables d'orientation sociale se sont révélées être plus importantes pour les garçons. La comparaison sociale contribuait aussi aux comportements de santé bénéfiques chez les garçons. Ces résultats soutiennent l'idée que le rôle des orientations sociales, telles que la compétitivité et la comparaison sociale, peut être assez différent dépendamment du sexe de l'individu et de la nature du comportement de santé. Tandis que la compétitivité peut agir comme facteur de risque pour la consommation de substances chez les garçons, la comparaison sociale peut agir comme facteur de protection. Il apparaît que les orientations sociales jouent un rôle moins grand en ce qui concerne les comportements de santé des filles. Il est nécessaire de focaliser davantage sur les différences de genre dans les influences reliées aux comportements de santé des adolescents. Las conductas de salud en adolescentes son

  19. Social orientations and adolescent health behaviours in Hungary.

    PubMed

    Piko, Bettina F; Skultéti, Dóra; Luszczynska, Aleksandra; Gibbons, Frederick X

    2010-02-01

    ôle que ces orientations sociales peuvent jouer dans les comportements de santé (à la fois néfastes et bénéfiques). Les données ont été recueillies auprès d'étudiants collégiaux (N = 548; âgés de 14 à 20 ans; 39.9% masculins) dans deux comtés du sud de la Hongrie. Les questionnaires auto-administrés contenaient des items portant sur les aspects sociodémographiques (tels que l'âge, le sexe, la scolarité des parents et le niveau économique), la performance scolaire, les comportements de santé, la compétitivité et la comparaison sociale. Des analyses de régression multiple suggèrent que ceux qui ont obtenu des scores supérieurs de compétitivité consommaient plus de substances, un patron qui n'était pas présent pour les comportements de santé bénéfiques. La comparaison sociale, cependant, était associée à de faibles niveaux de consommation de substances. De plus, en relation avec les comportements de santé néfastes, à la fois la compétitivité et la comparaison sociale interagissaient avec le sexe; les deux variables d'orientation sociale se sont révélées être plus importantes pour les garçons. La comparaison sociale contribuait aussi aux comportements de santé bénéfiques chez les garçons. Ces résultats soutiennent l'idée que le rôle des orientations sociales, telles que la compétitivité et la comparaison sociale, peut être assez différent dépendamment du sexe de l'individu et de la nature du comportement de santé. Tandis que la compétitivité peut agir comme facteur de risque pour la consommation de substances chez les garçons, la comparaison sociale peut agir comme facteur de protection. Il apparaît que les orientations sociales jouent un rôle moins grand en ce qui concerne les comportements de santé des filles. Il est nécessaire de focaliser davantage sur les différences de genre dans les influences reliées aux comportements de santé des adolescents. Las conductas de salud en adolescentes son

  20. Fleischmann seminar (fusion)

    ScienceCinema

    None

    2016-07-12

    "pictures, television out, no flash and camera, there will be a press section later on in the council room if Prof. Fleischmann will accept"..le DG C.Rubbia insiste pour cette discussion scientifique de ne pas filmer, autrement de bien quitter la salle, ce qui provoque un petit remue-ménage...

  1. Fleischmann seminar (fusion)

    SciTech Connect

    2007-10-25

    "pictures, television out, no flash and camera, there will be a press section later on in the council room if Prof. Fleischmann will accept"..le DG C.Rubbia insiste pour cette discussion scientifique de ne pas filmer, autrement de bien quitter la salle, ce qui provoque un petit remue-ménage...

  2. Speech Schopper

    ScienceCinema

    None

    2016-07-12

    Le DG H.Schopper prend congé de ses directeurs et collègues qui partent et remercie aussi les restants pour leur service; d'autres orateurs comme p.ex. Mons.Ullmann ainsi qu'un allemand prennent la parole.

  3. APPOLLO 9

    SciTech Connect

    2005-10-27

    le DG B.Grégory prend la parole et introduit le cosmonaute américain Russell Schweickart, qui fait un exposé sur la mission APPOLLO 9 et l'avenir de l'exploration spatiale avec présentation d'un film avec musique, mais sans parole, après commentaires et questions

  4. Speech Schopper

    SciTech Connect

    2006-11-03

    Le DG H.Schopper prend congé de ses directeurs et collègues qui partent et remercie aussi les restants pour leur service; d'autres orateurs comme p.ex. Mons.Ullmann ainsi qu'un allemand prennent la parole.

  5. Remarkable adsorptive removal of nitrogen-containing compounds from a model fuel by a graphene oxide/MIL-101 composite through a combined effect of improved porosity and hydrogen bonding.

    PubMed

    Ahmed, Imteaz; Jhung, Sung Hwa

    2016-08-15

    A composite was prepared by combining a highly porous metal-organic framework (MOF), MIL-101 (Cr-benzenedicarboxylate), and graphene oxide (GnO). The porosity of the composite increased appreciably by the addition of GnO up to a specific amount in the MOF, though further increases in the quantity of GnO was detrimental to porosity. The improved porosity of the GnO/MIL-101 composite was utilized for adsorptive denitrogenation (ADN) of a model fuel where indole (IND) and quinoline (QUI) were used as nitrogen-containing compounds (NCCs). It was found that both IND and QUI showed improved adsorption on the composite compared with pristine MIL-101 or GnO due to the improved porosity of the composite. Interestingly, the improvement in adsorption of IND was much higher than the quantity estimated for the porosity. Importantly, GnO/MIL-101 showed the highest adsorption capacities for NCCs. Irrespective of the studied solvents and co-presence of IND and QUI, the composite adsorbent performed ADN most effectively. This remarkable improvement is explained by the additional mechanism of hydrogen bonding between the surface functional groups of GnO and the hydrogen attached to the nitrogen atom of IND. This hydrogen bonding mechanism is also supported by the results of the adsorption of pyrrole and methylpyrrole. On the other hand, QUI does not show hydrogen-bonding capability, and therefore, its enhanced adsorption originates from only the increased porosity of the adsorbents.

  6. Oncocytome de la surrénale : Étude de cas.

    PubMed

    Chaari, Chiraz; Khabir, Abdelmajid; Mnif, Hela; Abid, Mohamed; Mhiri, Mohamed Nabil; Boudawara, Tahia Sellami

    2011-10-01

    RéSUMé: Nous rapportons ici un nouveau cas de cette entité afin de souligner les caractéristiques anatomocliniques utiles à son identification et ceci, en vue de la distinguer des corticosurrénalomes, qui sont de pronostic nettement plus sombre.

  7. Matiere sombre : Radioscopie d'un monde invisible

    NASA Astrophysics Data System (ADS)

    Jodra, S.; Harrois-Monin, F.; Bonnet-Bidaud, J. M.

    2002-05-01

    La face cachée de l'Univers est la cle de son evolution. Des resultats recents levent le voile sur l'energie sombre qui constitue la majeure partie du cote obscur du cosmos. Une bonne raison de faire le point sur l'autre composante invisible de l'Univers : la matiere "noire". Un portrait-robot circule deja.

  8. Allan Sandage : L'architecte de l'expansion

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1998-07-01

    Il fut de cette poignee de pionniers qui ouvrirent le monde extragalactique. Depuis pres de 50 ans, Allan Sandage poursuit la quete amorcee par le "maitre" Edwin Hubble : mesurer le taux d'expansion de l'Univers. Rencontre avec une legende vivante de la cosmologie...

  9. [Facial recognition and autism].

    PubMed

    Assumpçäo Júnior, F B; Sprovieri, M H; Kuczynski, E; Farinha, V

    1999-12-01

    Through the presentation of four facial expressions' illustrations, we evaluate the capacity of autistic children recognition, comparing with normal intelligence children and adults. The comparison of results was accomplished through the qui-square test. The differences observed were significant, showing that a disturbance of the facial expressions' perception is present in autistic children, and that it interferes directly in the social relationships.

  10. Radiations cosmiques : danger dans l'Espace

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.; Dzitko, H.

    2000-06-01

    Au sol, l'atmosphere nous protege plus ou moins bien. Mais dans l'espace ou a bord des avions de ligne, l'homme est directement expose aux rayonnements cosmiques qui peuvent etre mortels. Un veritable frein a la presence humaine prolongee dans l'espace. Une menace que les agences spatiales prennent tres au serieux.

  11. [The role of care assistants at the end of life].

    PubMed

    Estrate, Margot; Lacour, Frédérique

    2015-02-01

    Personal care assistants have a special place, at home, with patients at the end of their life. At the interface between carers, relatives and the person they take care of, they often live intense situations, in close contact. The Parisian palliative care network Quiétude shares their voice. PMID:26144828

  12. Syntactic and Prosodic Computations in the Resolution of Relative Clause Attachment Ambiguity by English-French Learners

    ERIC Educational Resources Information Center

    Dekydtspotter, Laurent; Donaldson, Bryan; Edmonds, Amanda C.; Fultz, Audrey Liljestrand; Petrush, Rebecca A.

    2008-01-01

    This study investigates the manner in which syntax, prosody, and context interact when second- and fourth-semester college-level English-French learners process relative clause (RC) attachment to either the first noun phrase (NP1) or the second noun phrase (NP2) in complex nominal expressions such as "le secretaire du psychologue qui se promene"…

  13. Hoja informativa de pruebas genéticas

    Cancer.gov

    Trata de pruebas genéticas para riesgos heredados de cáncer; incluye tipos de pruebas, para quién son, explicación y confidencialidad de los resultados. Ofrece información de pruebas genéticas a domicilio o pruebas para el consumidor.

  14. Awareness Training Program on Responsible Gambling for Casino Employees

    ERIC Educational Resources Information Center

    Giroux, Isabelle; Boutin, Claude; Ladouceur, Robert; Lachance, Stella; Dufour, Magali

    2008-01-01

    Over the last years, several comprehensive training programs for problem gambling have been developed and implemented in various casinos around the world. However, the efficacy of these programs has rarely been assessed and evaluated scientifically. A workshop called "Des gens qui font la difference" (People Making a Difference) was developed to…

  15. Sex differences in effects of excitotoxic spinal injury on below-level pain sensitivity.

    PubMed

    Acosta-Rua, Antonio J; Cannon, Richard L; Yezierski, Robert P; Vierck, Charles J

    2011-10-24

    Effects of excitotoxic injury to the thoracic gray matter on sensitivity to below-level nociceptive stimulation were evaluated for female and male Long-Evans rats. Operant escape and lick/guard (L/G) reflex responses to thermal stimulation were evaluated before and for 13-15 weeks after: 1) injections of quisqualic acid (QUIS) into the thoracic gray matter (T8-9), 2) laminectomy and spinal exposure and penetration without injection (sham) or 3) no surgical procedure (control). L/G responding to heat stimulation (44 °C) was unaffected for females and males following thoracic QUIS injections. Similarly, male escape performance was not significantly altered for 44 °C or 10 °C stimulation after QUIS injections or sham surgery. However, escape testing following QUIS and sham injections revealed increased heat sensitivity (44 °C) and decreased cold sensitivity (10 °C) for females. This selective effect is indicative of altered sympathetic activation by the thoracic injections. The effect of sham surgery suggests that female rats are vulnerable to ischemic injury during exposure and manipulation of the spinal cord. Escape from nociceptive heat and cold sensitivity of control males and females was unchanged over 13-15 weeks of testing. PMID:21943508

  16. Plant Stress Indicates Drought

    NASA Video Gallery

    Farmers across America rely on early drought warning systems to manage their crops. Americans everywhere rely on those farmers to provide food. A new drought tracking system called ESI helps by mon...

  17. 12 CFR 708a.5 - Notice to NCUA.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... credit union relies for its authority to convert to a mutual savings bank on a state law parity provision... regulatory authority agrees that it may rely on the state law parity provision as authority to convert;...

  18. 12 CFR 708a.105 - Notice to NCUA.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... credit union relies for its authority to convert to a mutual savings bank on a state law parity provision... regulatory authority agrees that it may rely on the state law parity provision as authority to convert;...

  19. 12 CFR 708a.105 - Notice to NCUA.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... credit union relies for its authority to convert to a mutual savings bank on a state law parity provision... regulatory authority agrees that it may rely on the state law parity provision as authority to convert;...

  20. 12 CFR 708a.105 - Notice to NCUA.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... credit union relies for its authority to convert to a mutual savings bank on a state law parity provision... regulatory authority agrees that it may rely on the state law parity provision as authority to convert;...

  1. 24 CFR 966.56 - Procedures governing the hearing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... controvert evidence relied on by the PHA or project management, and to confront and cross-examine all witnesses upon whose testimony or information the PHA or project management relies; and (5) A decision...

  2. Effective Forces Between Diamagnetic and Paramagnetic Ions in D 2 O at Low and Moderate Ionic Strengths: An NMR Relaxation Study

    NASA Astrophysics Data System (ADS)

    Sacco, A.; Belorizky, E.; Jeannin, M.; Gorecki, W.; Fries, P. H.

    1997-09-01

    Debye-Hückel screening formalism, which can be reasonably used up to moderate ionic strengths. On étudie la dynamique de plusieurs paires d'ions attractifs et répulsifs en solution aqueuseà des forces ioniques atteignant 1 mol l^{-1}. La mesure des taux de relaxation nucléaire longitudinale des protons des ions diamagnétiques fournit l'information expérimentale. On a choisi les solutions ioniques de sorte que le principal mécanique de relaxation de ces protons soit les fluctuations temporelles de leur interaction dipolaire magnétique avec les spins électroniques des ions paramagnétiques. Cette interaction dépend fortement du potentiel des forces moyennes (PMF) ion-ion et des coefficients d'auto-diffusion ioniques. On calcule les corrélations spatiales ion-ion et les PMF associés à l'aide d'une nouvelle approximation des équations intégrales de la mécanique statistique des liquides. Ce formalisme traite tous les ions comme des particules discrètes. Il est fondé sur les PMF d'infinie dilution paires d'ions. Il mélange une théorie de Born-Oppenheimer pour la dilution infinie avec une approximation de type McMillan-Mayer pour tenir compte de la concentration ionique. Il va au-delà du modèle d'écrantage de Debye-Hückel où une distribution continue de charge rend compte des effets des ions discrets environnants. Il est relié au concept des constantes diélectriques locales qui généralisent la constante diélectrique macroscopique usuelle et sont fonction des distances ion-ion. On a mesuré les coefficients d'auto-diffusion des ions diamagnétiques par des techniques RMN de gradients pulsés de champ magnétique (PMFG), appliquées aux protons résonnants. Dans les solutions paramagnétiques contenant plusieurs espèces protonées, les précautions particulières à prendre sont discutées en détail. Dans toutes les solutions considérées la théorie rend bien compte des taux de relaxation en fonction des charges des ions, de leurs

  3. Mesure de la fraction d'evenements a quatre quarks dans les desintegrations multihadroniques du boson Z au LEP

    NASA Astrophysics Data System (ADS)

    Lefebvre, Eric

    Cette thèse propose de tester la Chromodynamique Quantique (QCD) en effectuant une mesure précise d'une des trois constantes fondamentales du groupe de symétrie SU(3) utilisé pour décrire la physique des interactions fortes. Cette constante fondamentale, appelée TF, est reliée à certains états finaux spécifiques des désintégrations du Z0. Ces états apparaissent sous forme de perturbations du deuxième ordre en as et sont illustrés par des diagrammes de Feynman. À cet ordre, la chromodynamique prévoit deux types de diagrammes de Feynman distincts; le premier contient, un quark, un antiquark et deux gluons, et le second, deux quarks et deux antiquarks. La constante TF est directement proportionnelle à la fraction d'événements à deux quarks et deux antiquarks qui est l'objet de notre mesure. Notre mesure est fondée sur l'étude des événements à quatre partons dans l'état final. Ces quatre partons, en s'hadronisant, produisent quatre jets de particules qui peuvent être détectés expérimentalement et identifiés à l'aide d'algorithmes de reconstruction des jets. Des observables angulaires nous permettent de faire une discrimination parmi les états finaux de la désintégration du Z0, et ainsi déterminer la valeur de la fraction d'événements à deux quarks et deux antiquarks fq. Cette fraction peut s'exprimer par le rapport de la fraction observée expérimentalement fexq sur la fraction théorique fthq , R4q=fex qfthq. Afin d'améliorer la mesure de cette fraction et de diminuer le bruit causé par une contamination des événements d'ordres supérieurs, nous avons développe une méthode d'extrapolation. Cette méthode s'appuie sur la caractérisation de l'espace de phase des événements, exprimée par les paramètres yij. Les mesures de R4q que nous obtenons sont: R4q=2,27+0,29 -0,56 à l'aide d'une méthode conventionnelle avec la condition de sélection y34 > 0,020 > y45, et R4q=1,22+0,56 -0

  4. Microbial communities in the deep subsurface

    NASA Astrophysics Data System (ADS)

    Krumholz, Lee R.

    The diversity of microbial populations and microbial communities within the earth's subsurface is summarized in this review. Scientists are currently exploring the subsurface and addressing questions of microbial diversity, the interactions among microorganisms, and mechanisms for maintenance of subsurface microbial communities. Heterotrophic anaerobic microbial communities exist in relatively permeable sandstone or sandy sediments, located adjacent to organic-rich deposits. These microorganisms appear to be maintained by the consumption of organic compounds derived from adjacent deposits. Sources of organic material serving as electron donors include lignite-rich Eocene sediments beneath the Texas coastal plain, organic-rich Cretaceous shales from the southwestern US, as well as Cretaceous clays containing organic materials and fermentative bacteria from the Atlantic Coastal Plain. Additionally, highly diverse microbial communities occur in regions where a source of organic matter is not apparent but where igneous rock is present. Examples include the basalt-rich subsurface of the Columbia River valley and the granitic subsurface regions of Sweden and Canada. These subsurface microbial communities appear to be maintained by the action of lithotrophic bacteria growing on H2 that is chemically generated within the subsurface. Other deep-dwelling microbial communities exist within the deep sediments of oceans. These systems often rely on anaerobic metabolism and sulfate reduction. Microbial colonization extends to the depths below which high temperatures limit the ability of microbes to survive. Energy sources for the organisms living in the oceanic subsurface may originate as oceanic sedimentary deposits. In this review, each of these microbial communities is discussed in detail with specific reference to their energy sources, their observed growth patterns, and their diverse composition. This information is critical to develop further understanding of subsurface

  5. Mecanique et mecanisme de la dechirure des materiaux textiles

    NASA Astrophysics Data System (ADS)

    Triki, Ennouri

    Cette thèse vise à apporter une contribution à l’étude et à la modélisation de la déchirure des textiles et des textiles enduits. Notons que la résistance à la déchirure est l’une des caractéristiques mesurées pour les équipements de protection contre les agresseurs mécaniques en milieu de travail. Jusqu'à présent, ce comportement en déchirure a été étudié en mesurant la force de déchirure et le travail de déchirure. De fait, aucun critère de rupture en déchirure n’existe actuellement. Par conséquent, en s’inspirant de la théorie du Griffith et de la mécanique de la rupture, une formulation d’un nouveau critère de rupture des structures textiles a été proposée. Cette approche offre la possibilité de déterminer d’une manière plus précise l’énergie nécessaire pour la création d’une nouvelle surface de rupture. Ce critère nous permet d’analyser l’effet des caractéristiques des tissus sur la variation de l’énergie de rupture. Cette étude montre que la résistance au glissement des fils dans la structure est le principal facteur qui contrôle la propagation de la fissure. En se basant sur la théorie de la mécanique de la rupture, un modèle de calcul de l’énergie de rupture par déchirure a été aussi élaboré. Ce modèle de déchirure relie l’énergie aux paramètres caractérisant les phénomènes affectant la déchirure des tissus, notamment la force de glissement et la force à la rupture des fils. Cette modélisation a tenu compte de certaines caractéristiques des tissus tels que l’épaisseur du matériau, la densité des fils, etc. Par l’étude de la variation de l’énergie de rupture par déchirure en fonction du rapport établi entre la force à la rupture et la force de glissement d’un fil ( FYB/FS), l’effet des mécanismes de la propagation de la fissure dans les tissus sur leur comportement en déchirure a été aussi observé. Les résultats obtenus

  6. Patient Prioritization Preferences among Physiotherapy Entry-Level Students: The Importance of Chronic Pain.

    PubMed

    Laliberté, Maude; Ehrmann Feldman, Debbie

    2013-01-01

    Objectif : Étudier les préférences des étudiants en physiothérapie au niveau débutant sur le plan de l'attribution d'une priorité aux patients, en particulier aux patients vivant avec une douleur chronique. Méthode: Après une discussion en groupe, 249 étudiants canadiens en physiothérapie au niveau débutant ont rempli un questionnaire basé sur cinq scénarios distincts (cas de patients fictifs). On a demandé aux répondants d'attribuer une priorité aux patients (P1=priorité la plus élevée, P5=priorité la plus basse). Résultats : Les étudiants en physiothérapie ont accordé la priorité la plus élevée aux patients vivant avec de la douleur chronique et aux patients qui venaient de subir une intervention chirurgicale. Le patient âgé et le patient qui avait un déficit cognitif ont reçu une priorité plus basse. Conclusions : Les étudiants en physiothérapie accordent la plus grande priorité à un diagnostic de douleur chronique. Les publications montrent toutefois que la douleur chronique constitue la priorité la plus basse dans les outils de triage des départements de physiothérapie. Il pourrait y avoir un virage au niveau des préférences entre la période qui précède la pratique (étudiants) et celle qui la suit (clinicien) en ce qui a trait aux patients vivant avec une douleur chronique.

  7. Surgical treatment of intractable pelvic, groin, and perineal neuropathic pain in a gynaecologic patient: triple neurectomy.

    PubMed

    Farrell, Scott A; Clermont, Marie-Eve

    2015-02-01

    Contexte : Les gynécologues à qui l’on demande d’évaluer des patientes qui présentent des douleurs affectant les organes génitaux ne disposent généralement pas de la formation qui leur permettrait de tenir compte des causes neurogènes de la douleur; d’ordre général, les interventions chirurgicales permettant d’éliminer cette douleur ne leur sont également pas familières. Cas : Une femme de 54 ans qui avait subi de multiples laparotomies (césarienne, hystérectomie abdominale, prise en charge de kystes ovariens et libération d’adhérences) par l’intermédiaire d’une approche abdominale transversale connaissait de graves douleurs neuropathiques inguinales, labiales et périnéales affectant le côté gauche depuis 7-8 mois. Une neurectomie visant les nerfs ilio-hypogastrique, ilio-inguinal et génitocrural a été menée. À la suite de l’intervention, la patiente en est venue à connaître une résolution totale de la douleur. Conclusion : La présence de douleurs neuropathiques devrait être envisagée dans le cadre du diagnostic différentiel chez les femmes qui présentent des antécédents importants de chirurgie abdominale basse. La neurectomie constitue alors un traitement efficace.

  8. Transport de particules massives dans un fluide turbulent: Application a l'erosion due au sable sur les parois d'une turbine hydraulique

    NASA Astrophysics Data System (ADS)

    Bergeron, Stephen

    Le transport de particules massives par un champ turbulent est un vaste domaine de la mécanique des fluides. Il possède de nombreuses applications comme par exemple le transport de sable dans une turbine hydraulique. En raison de la dureté des grains de quartz et des grandes vitesses de collision avec les parois métalliques, un phénomène d'érosion intensif se produit. Les dommages résultants peuvent diminuer le rendement de la turbine au cours des quelques mois suivant la mise en opération. L'objectif de cette thèse est de mettre au point un outil permettant de prédire ces zones d'érosion. Ce projet de recherche en contexte industriel a été réalisé en collaboration avec la compagnie General Electric Hydro du Canada. Dans un régime hautement turbulent, il est possible d'obtenir une expression suffisamment générale en utilisant une formulation partiellement empirique: l'équation de Basset- Boussinesq-Oseen modifiée. Ce choix de modèle tient compte du niveau de précision recherché et de la méthode numérique employée afin de résoudre la phase fluide. Il permet aussi d'éliminer plusieurs ambiguïtés fréquemment rencontrées dans la littérature et implementées dans certains codes commerciaux courants. La formulation mathématique du problème est effectuée dans un espace mixte Euler-Lagrange. Les paramètres dynamiques sont relies au type de particules et à l'intensité de la turbulence. Le code numérique résultant est le plus performant développé à ce jour (août 1998). Les trajectoires de plusieurs centaines de milliers de particules peuvent être simulées et visualisées de manière interactive sur une station de travail (SGI R4K, R8K et R10K). L'utilisateur du logiciel est libre de se déplacer dans l'espace à l'aide d'un environnement similaire a un ``simulateur de vol''. Il peut ainsi analyser les détails du processus d'érosion de même que l'écoulement du fluide dans la turbine. Les zones d'érosion obtenues à l

  9. 10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... assurance that items relied on for safety will be available and reliable to perform their function when... utility services. (8) Inspection, testing, and maintenance. The design of items relied on for safety must... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based...

  10. 10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... assurance that items relied on for safety will be available and reliable to perform their function when... utility services. (8) Inspection, testing, and maintenance. The design of items relied on for safety must... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based...

  11. A martyr for modernity: Qiu Jin -- feminist warrior, and revolutionary.

    PubMed

    Fan, H; Mangan, J A

    2001-01-01

    Qui Jin, at one level, was an oriental twentieth-century Judith, the mythical Jewish widow from Bethulia who cut off the head of Holofernes, the Assyrian general besieging the city, thus saving the Israelites from destruction. Qui Jin was, as Judith was, a self-reliant heroine who when others seemed 'helpless and demoralized undertook to save them single-handedly', or in her case virtually single-handedly. This, of course, was both her making and her unmaking. In Chinese terms the story of Qui Jin, like the story of Judith if less famous, less publicised, more recent, is the story of an icon at once central and at the same time marginal to tradition. She contradicted the most cherished customs on Confucian Chinese culture. She was a radical force who thrust her way to the centre of the concentric circles of customs surrounding this culture and was pushed back to the margins by conservatism. Nevertheless Qui Jin was not without success. She challenged a long-established mythology of exclusively masterful patriarchy - and created a counter myth of purposeful patriotic feminism. She was a counter-cultural icon who changed perceptions of Chinese femininity. She gave courage, confidence and purpose to those women who came after her and absorbed her ambitions for modern Chinese womanhood. For them she was a modern national heroine and a personification of a modern nation of equal men and women. For Qui Jin the body was an instrument of female revolution to be trained, strengthened and prepared for confrontation. As a revolutionary militant she was a failure; as a revolutionary talisman she was a success. For the Chinese women of the 1911 Revolution hers was an exemplary emancipatory story: subscribe, struggle, sacrifice. Patriotism through feminism is the purpose. Her heroism was firmly outside the historic patriarchal order. Her adulation is thus all the more remarkable because of the profound traditions she rejected, the controversial mannerisms she adopted, the

  12. Effect of Menstrual Age on Failure of Medical Management in Women With Early Pregnancy Loss.

    PubMed

    Lavecchia, Melissa; Abenhaim, Haim A

    2015-07-01

    Objectif : Les femmes qui connaissent une fausse couche précoce et qui présentent un âge gestationnel < 8 semaines sont considérées comme étant de bonnes candidates pour une prise en charge médicale. Notre étude avait pour objectif d’évaluer l’effet de l’âge menstruel sur l’issue de la prise en charge médicale des femmes qui connaissent une fausse couche à un âge gestationnel estimé à < 8 semaines par échographie. Méthodes : Nous avons mené une étude de cohorte rétrospective qui portait sur toutes les femmes qui ont, entre 2011 et 2013, obtenu leur congé du service des urgences en raison d’un diagnostic de fausse couche précoce, qui ont été traitées au moyen de misoprostol et chez qui l’échographie a déterminé que l’âge gestationnel était inférieur à huit semaines. Nous avons utilisé une régression logistique pour estimer l’effet de l’âge menstruel sur l’échec de la prise en charge médicale (lequel était défini par la nécessité de procéder à une dilatation-curetage [DC] ou d’effectuer un retour imprévu au service des urgences [RISU]). Résultats : Parmi 823 femmes enceintes s’étant présentées au service des urgences en raison de saignements au premier trimestre, 199 ont connu une fausse couche à < 8 semaines (âge gestationnel déterminé par échographie) et ont obtenu leur congé de l’hôpital à la suite de la mise en œuvre d’un traitement au misoprostol. Le risque de DC et de RISU était proportionnel à l’âge menstruel. Plus particulièrement, le risque de DC était de 11,8% à < 8 semaines, de 18,5 % à 8-9 semaines, de 25,3 % à 10-11 semaines et de 30,6 % à ≥ 12 semaines (P < 0,05). Le risque de RISU était de 14,7 % à < 8 semaines, de 27,8 % à 8-9 semaines, de 36,0 % à 10-11 semaines et de 41,7 % à ≥ 12 semaines (P < 0,05). Conclusion : La hausse de l’âge gestationnel (en fonction des dates menstruelles) est associée à une

  13. Provoked Vestibulodynia and the Health Care Implications of Comorbid Pain Conditions.

    PubMed

    Lester, Robynn A; Brotto, Lori A; Sadownik, Leslie A

    2015-11-01

    Objectif : La douleur sexuelle attribuable à la vestibulodynie provoquée (VDP) est un trouble de douleur chronique qui affecte jusqu’à 16 % des femmes. Les femmes qui présentent une VDP pourraient en venir à signaler d’autres troubles de douleur chronique. Cette étude avait pour objectif (1) d’identifier la prévalence des troubles de douleur chronique auto-signalés au sein d’un échantillon de femmes ayant obtenu un diagnostic de VDP et cherchant à obtenir un traitement; et (2) de comparer les caractéristiques démographiques et cliniques et les besoins en soins de santé des femmes qui ne présentent qu’une VDP et des femmes qui présentent une VDP et au moins deux troubles de douleur chronique auto-signalés. Méthodes : Nous avons évalué les caractéristiques de 236 femmes ne présentant qu’une VDP et de 55 femmes présentant une VDP et une douleur chronique comorbide au moyen d’un questionnaire standardisé, de l’Inventaire de dépression de Beck, du State-Trait Anxiety Inventory, du Pain Vigilance and Awareness Questionnaire et de la Female Sexual Distress Scale. Résultats : Par comparaison avec les femmes qui ne présentaient qu’une VDP, les femmes qui présentaient celle-ci et une autre douleur concomitante ont signalé une douleur d’une durée significativement prolongée, une douleur irradiant vers d’autres parties de la vulve et une douleur nuisant à diverses activités de la vie quotidienne. Les femmes de ce groupe étaient également significativement plus susceptibles que les femmes ne présentant qu’une VDP d’avoir consulté un plus grand nombre de gynécologues et de s’être rendues un plus grand nombre de fois au cabinet de leur gynécologue. Elles étaient plus susceptibles d’avoir fait l’essai d’anticonvulsivants, d’antidépresseurs et d’une thérapie anti-stress / de relaxation pour contrer leur VDP, et également plus susceptibles de connaître des allergies et des sensibilités cutan

  14. A martyr for modernity: Qiu Jin -- feminist warrior, and revolutionary.

    PubMed

    Fan, H; Mangan, J A

    2001-01-01

    Qui Jin, at one level, was an oriental twentieth-century Judith, the mythical Jewish widow from Bethulia who cut off the head of Holofernes, the Assyrian general besieging the city, thus saving the Israelites from destruction. Qui Jin was, as Judith was, a self-reliant heroine who when others seemed 'helpless and demoralized undertook to save them single-handedly', or in her case virtually single-handedly. This, of course, was both her making and her unmaking. In Chinese terms the story of Qui Jin, like the story of Judith if less famous, less publicised, more recent, is the story of an icon at once central and at the same time marginal to tradition. She contradicted the most cherished customs on Confucian Chinese culture. She was a radical force who thrust her way to the centre of the concentric circles of customs surrounding this culture and was pushed back to the margins by conservatism. Nevertheless Qui Jin was not without success. She challenged a long-established mythology of exclusively masterful patriarchy - and created a counter myth of purposeful patriotic feminism. She was a counter-cultural icon who changed perceptions of Chinese femininity. She gave courage, confidence and purpose to those women who came after her and absorbed her ambitions for modern Chinese womanhood. For them she was a modern national heroine and a personification of a modern nation of equal men and women. For Qui Jin the body was an instrument of female revolution to be trained, strengthened and prepared for confrontation. As a revolutionary militant she was a failure; as a revolutionary talisman she was a success. For the Chinese women of the 1911 Revolution hers was an exemplary emancipatory story: subscribe, struggle, sacrifice. Patriotism through feminism is the purpose. Her heroism was firmly outside the historic patriarchal order. Her adulation is thus all the more remarkable because of the profound traditions she rejected, the controversial mannerisms she adopted, the

  15. Sexual and gender minority peoples' recommendations for assisted human reproduction services.

    PubMed

    Ross, Lori E; Tarasoff, Lesley A; Anderson, Scott; Green, Datejie; Epstein, Rachel; Marvel, Stu; Steele, Leah S

    2014-02-01

    Objectif : Chercher à connaître les recommandations que formuleraient les personnes lesbiennes, gaies, bisexuelles, transgenres et allosexuelles (LGBTQ) en ce qui concerne l’offre de services de procréation assistée (PA) à leurs communautés. Méthodes : En utilisant un guide semi-structuré, nous avons interviewé un échantillon choisi à dessein de 66 personnes s’identifiant comme étant LGBTQ et provenant de partout dans la province de l’Ontario qui avaient utilisé ou qui avaient envisagé d’utiliser des services de PA depuis 2007. Résultats : Les participantes étaient principalement des femmes cisgenres (non transgenres), blanches, ayant une partenaire du même sexe et vivant en milieu urbain qui comptaient des niveaux relativement élevés de scolarité et de revenu. Les participantes ont formulé des recommandations visant l’apport de modifications aux aspects suivants de l’offre de services de PA : (1) accès à des renseignements pertinents pour les personnes LGBTQ, (2) adoption de pratiques axées sur la patiente par les fournisseurs de services de PA, (3) formation et éducation des fournisseurs de services à l’égard des enjeux et des besoins des personnes LGBTQ, (4) accroissement de la visibilité des personnes LGBTQ en milieu clinique et (5) octroi d’une attention aux lacunes en matière de services qui préoccupent particulièrement les personnes LGBTQ. Conclusion : Bon nombre des recommandations formulées par les participantes à l’étude illustrent la façon dont l’adoption de modèles axés sur la patiente pourrait combler les inégalités en ce qui concerne l’offre de services aux personnes LGBTQ et à d’autres patientes pouvant avoir des besoins particuliers en matière de PA. Nos résultats semblent indiquer que des ressources éducatives devraient être mises à la disposition des fournisseurs de services pour leur permettre de mettre en œuvre de telles pratiques axées sur les patientes et d’offrir des

  16. Ureteric injury during transvaginal ultrasound guided oocyte retrieval.

    PubMed

    Vilos, Angelos G; Feyles, Valter; Vilos, George A; Oraif, Ayman; Abdul-Jabbar, Hanin; Power, Nicholas

    2015-01-01

    Contexte : Dans le cadre de la fécondation in vitro, la récupération d’ovocytes guidée par échographie transvaginale constitue une intervention qui est régulièrement menée partout dans le monde et qui a permis d’atténuer le taux de lésion intra-abdominale de façon considérable, par comparaison avec le recours à des interventions laparoscopiques. Toutefois, ces lésions n’ont pas été éradiquées pour autant. Cas : Nous signalons le cas d’une patiente de 37 ans qui a eu recours à la FIV et qui a subi une lésion urétérale au cours de la récupération des ovocytes; la présence de cette lésion a été constatée tôt et a fait l’objet d’une prise en charge (au moyen d’endoprothèses urétérales) qui s’est soldée en une résolution complète. Dans le cadre d’un cycle de FIV subséquent, la présence d’endoprothèses dans les uretères a permis une meilleure visualisation, ce qui a mené à la réussite de la récupération d’ovocytes et de la grossesse subséquente. Conclusion : Des lésions urétérales peuvent survenir dans le cadre de la récupération d’ovocytes guidée par échographie transvaginale. La rapidité de l’identification de ces lésions est d’une importance cruciale pour la réussite du traitement. La pose d’endoprothèses dans les uretères constitue la modalité thérapeutique la plus courante et peut être utilisée pour mieux identifier les uretères dans le cadre des interventions subséquentes de récupération d’ovocytes.

  17. Transfert radiatif numerique pour un code SPH

    NASA Astrophysics Data System (ADS)

    Viau, Joseph Edmour Serge

    2001-03-01

    Le besoin de reproduire la formation d'etoiles par simulations numeriques s'est fait de plus en plus present au cours des 30 dernieres annees. Depuis Larson (1968), les codes de simulations n'ont eu de cesse de s'ameliorer. D'ailleurs, en 1977, Lucy introduit une autre methode de calcul venant concurrencer la methode par grille. Cette nouvelle facon de calculer utilise en effet des points a defaut d'utiliser des grilles, ce qui est une bien meilleure adaptation aux calculs d'un effondrement gravitationnel. Il restait cependant le probleme d'ajouter le transfert radiatif a un tel code. Malgre la proposition de Brookshaw (1984), qui nous montre une formule permettant d'ajouter le transfert radiatif sous la forme SPH tout en evitant la double sommation genante qu'elle implique, aucun code SPH a ce jour ne contient un transfert radiatif satisfaisant. Cette these presente pour la premiere fois un code SPH muni d'un transfert radiatif adequat. Toutes les difficultes ont pu etre surmontees afin d'obtenir finalement le transfert radiatif "vrai" qui survient dans l'effondrement d'un nuage moleculaire. Pour verifier l'integrite de nos resultats, une comparaison avec le nonisothermal test case de Boss & Myhill (1993) nous revele un resultat fort satisfaisant. En plus de suivre fidelement la courbe de l'evolution de la temperature centrale en fonction de la densite centrale, notre code est exempt de toutes les anomalies rencontrees par les codes par grille. Le test du cas de la conduction thermique nous a lui aussi servit a verifier la fiabilite de notre code. La aussi les resultats sont fort satisfaisants. Faisant suite a ces resultats, le code fut utilise dans deux situations reelles de recherche, ce qui nous a permis de demontrer les nombreuses possibilites que nous donne notre nouveau code. Dans un premier temps, nous avons tudie le comportement de la temperature dans un disque d'accretion durant son evolution. Ensuite nous avons refait en partie une experience de Bonnell

  18. Application de l’analyse des séries chronologiques à la projection d’effectifs de population scolaire par la méthode des composantes

    PubMed Central

    Smith, Herbert L.

    2016-01-01

    Cet article veut montrer qu’on peut réécrire des modèles démographiques en vue de réaliser des projections par cohorte, en les transposant dans un modèle économétrique vecteur autoré-gressif (VAR). De cette façon, la méthode des composantes se dote d’un cadre stochastique qui étend son envergure. Le potentiel de cette perspective est illustré à travers l’exemple d’une projection d’effectifs de population scolaire. Il met en valeur une série d’équations qui permet de vérifier la validité de plusieurs choix de modélisations habituellement utilisées dans le domaine de la prévision. PMID:27346921

  19. L'Aventure du LHC

    ScienceCinema

    None

    2016-07-12

    Cette présentation s’adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l’engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  20. Arteria lusoria associée à un tronc bi carotidien: à propos d'un cas et revue de la littérature

    PubMed Central

    Khnaba, Safae; Menany, Meryem; Moukinebillah, Mouna; Amil, Touriya; Radouane, Bouchayb

    2015-01-01

    L'arteria lusoria ou artère sous Clavière droite retro-œsophagienne constitue la malformation de l'arc aortique la plus fréquente, elle peut être associée à d'autres anomalies congénitales du cœur et des gros vaisseaux, notamment le tronc bi carotidien qui constitue un tronc commun donnant naissance aux deux artères carotides primitives internes. Nous rapportons le cas d'une patiente chez qui on a diagnostiqué un adénocarcinome gastrique, le scanner thoraco-abdominopelvien réalisé dans le cadre de son bilan d'extension a permis la découverte fortuite d'une artère aberrante retro-œsophagienne associé à un tronc bi carotidien. PMID:27047617

  1. Une localisation exceptionnelle de la tuberculose vertébrale Mal de Pott sous-occipital

    PubMed Central

    Yahyaoui, Sana; Majdoub, Senda; Zaghouani, Houneida; Fradj, Hosni Ben; Bakir, Dejla; Bouajina, Elyes; Kraiem, Chakib

    2013-01-01

    Le mal de Pott est la forme la plus commune de la tuberculose osseuse touchant essentiellement le rachis dorso-lombaire. La localisation sous-occipitale reste exceptionnelle. Le diagnostic de cette entité est le plus souvent tardif ce qui expose à des complications graves. Les radiographies standard ne sont parlantes qu’à un stade tardif de la maladie, d'où l'intérêt de l'imagerie moderne notamment la tomodensitométrie (TDM) et l'imagerie par résonance magnétique (IRM) qui permettent un diagnostic précoce. Nous rapportons un nouveau cas de tuberculose sous-occipitale. Le diagnostic était posé sur l'imagerie en coupe et confirmé histologiquement à la biopsie transorale. Sont rappelés les aspects en imagerie de cette localisation particulière du mal de Pott. PMID:23819005

  2. Factory to faculty: socioeconomic difference and the educational experiences of university professors.

    PubMed

    Haney, Timothy J

    2015-05-01

    Numerous essays exist on the lived experiences of academics from working-class or poverty-class origins. Yet, to date, there exists no systematic analysis of the class origins of university faculty members. This study utilizes surveys from a random sample of full-time university professors at all 95 Canadian universities affiliated with the Association of Universities and Colleges of Canada (AUCC) to analyze the ways in which socioeconomic background impacts experiences within university and graduate school. Findings indicate that several measures of socioeconomic background are indeed significant predictors of this experience. Qualitative data reveal that working-class faculty members are hyper-aware of the ways in which their class backgrounds affected their educational trajectories; while conversely, academics from middle-class backgrounds were also reflective about the ways in which they were privileged. The paper concludes with implications for developing public policy that shifts focus away from apolitical discussions of diversity, toward promoting inclusivity for those from working-class or lower-income backgrounds. Il existe de nombreux travaux concernant les expériences vécues par des académiques qui font parties de différentes classes sociales, particulièrement les classes ouvrières. Par contre, jusqu'à date, il n'existe aucune analyse systématique concernant les classes d'origines des membres du corps professoral qui travaillent aux universités. Cette étude utilise des enquêtes qui ont été obtenues avec un échantillon aléatoire de professeurs qui travaillent à temps plein aux 95 universités Canadiennes affiliées avec "L'association des Universités et Collèges du Canada" (AUCC). Cette étude analyse les façons que le statut socio-économique de la famille affecte les expériences à l'université et aux études supérieures. Les résultats quantitatifs démontrent que plusieurs mesures de statut socio-économique prédisent ces exp

  3. Enantiomer separation of acidic chiral compounds on a quinine-silica/zirconia hybrid monolith by capillary electrochromatography.

    PubMed

    Tran, Le Ngoc; Park, Jung Hag

    2015-05-29

    A weak anion-exchanger chiral selector, quinine-incorporated silica/zirconia hybrid monolithic (QUI-S/ZHM) capillary column was prepared by sol-gel technology. The performance of the QUI-S/ZHM column was investigated for enantioresolution of a set of acidic chiral drugs and dinitrobenzoyl (DNB)-amino acids by capillary electrochromatography in aqueous organic mobile phases composed of acetonitrile (ACN) and triethylammonium acetate (TEAA) buffer. Effects of several parameters including the ACN content, concentration and pH of the mobile phase on the chiral separation were examined. Baseline resolutions of all the compounds were obtained in the mobile phase consisting of 70:30 ACN/TEAA (10mM, pH 6) under applied voltage of -10kV at 25°C within 20min.

  4. Cancer du sein historique à propos d'un cas!!! Comment réagir

    PubMed Central

    Laghzaoui, Omar

    2016-01-01

    Le cancer du sein localement avancé est une entité qui se fait rare dans les pays développés alors qu'on continue de recevoir des patientes à un stade avancé dans les pays africains. Nous proposant le cas d'une patiente intellectuelle prise en charge à l'hôpital militaire, Meknès, Maroc; qui a décelé la présence d'un nodule du sein droit par l'autopalpation mais elle n'a consulté le médecin que six mois après, dans un état historique de cancer du sein localement avancé. Le but de notre publication est donc de soulever les anomalies contemporaines aboutissant au retard diagnostic du cancer du sein et de proposer des solutions pour mieux sensibiliser la population. PMID:27642397

  5. Le zona ophtalmique: une dermatose rare chez l'enfant

    PubMed Central

    Zakia, Douhi; Meziane, Marieme; Salim, Gallouj; Zahra, Mernissi Fatima

    2015-01-01

    Le zona est dû a une réactivation du virus varicelle-zona (VZV) qui reste quiescent dans les ganglions sensitifs dorsaux après la varicelle. Le zona de l'enfant est rare et particulièrement la forme ophtalmique, qui peut être responsable de complications oculaires graves nécessitant une prise en charge adéquate et précoce. Il est parfois associé à des douleurs post-zostériennes dont le traitement est difficile. L'aciclovir per os administré dans les 72 heures après l’éruption a prouvé son efficacité dans la prévention des complications oculaires. Nous en rapportant un nouveaux cas chez un garçon immunocompétent de 9 ans, sans notion de varicelle antérieure. PMID:26955408

  6. Circular structures of Bajada del Diablo (Argentina): geophysical signatures

    NASA Astrophysics Data System (ADS)

    Prezzi, C. B.; Orgeira, M. J.; Martinez, O.; Acevedo, R. D.; Ponce, F.; Goldmann, G.; Magneres, I.; Rabassa, J.

    2016-05-01

    Bajada del Diablo is located in the Northern Patagonian Massif, Chubut, Argentina. The study area includes several circular structures found in Miocene olivine basalts of the Quiñelaf Eruptive Complex and in the Late Pliocene/Early Pleistocene Pampa Sastre conglomerates. An impact origin has been proposed for these circular structures. With the aim of further investigate the proposed impact origin, topographic, gravimetric, magnetic, resistivity, palaeomagnetic and electromagnetic surveys in two circular structures (`8' and `G') located in Pampa Sastre conglomerates and in basalts of the Quiñelaf Eruptive Complex were carried out. The new geophysical results support the hypothesis of an impact origin. However, the confirmation of such an origin through the findings of shock metamorphism evidences and/or the recovery of meteorites remains elusive.

  7. Is Any Press Good Press? The Impact of Media Portrayals of Infertility on Young Adults' Perceptions of Infertility.

    PubMed

    Sangster, Sarah L; Lawson, Karen L

    2015-12-01

    Objectif : L’infertilité suscite bien des préoccupations de nos jours en Amérique du Nord. La Société des obstétriciens et gynécologues du Canada préconise la mise en œuvre d’efforts visant la sensibilisation du public à l’égard des questions entourant l’infertilité. Bien que la sensibilisation du public constitue, en principe, l’un des objectifs fondamentaux des médias d’information, la question de savoir si ces derniers collaborent de façon efficace avec la profession médicale à cet égard (et plus particulièrement en ce qui concerne la sensibilisation des jeunes femmes) demeure trouble. De récentes études semblent indiquer que la presse écrite tend à utiliser des stratégies grandement alarmistes en ce qui concerne la communication des nouvelles traitant de l’infertilité; cependant, les effets de ces stratégies sur le public demeurent inconnus. Cette étude avait pour objectif de comparer et de comprendre les effets des stratégies de communication grandement alarmistes et peu alarmistes sur le public visé par les nouvelles traitant de l’infertilité. Méthodes : Dans le cadre de cette expérience, 131 étudiants de premier cycle ont été affectés au hasard à un groupe devant lire des articles de journaux qui, à notre avis, utilisaient des stratégies de communication grandement alarmistes pour aborder le sujet de l’infertilité ou à un groupe devant lire des articles de journaux qui, à notre avis, utilisaient des stratégies peu alarmistes pour aborder ce sujet. Les participants ont par la suite rempli un questionnaire mesurant divers paramètres psychologiques, affectifs et liés aux connaissances, et ce, pour nous permettre d’évaluer les effets de l’exposition à chacun de ces types de nouvelles. Résultats : Les participants qui ont été exposés à des stratégies de communication grandement alarmistes ont présenté des taux accrus de sensibilité personnelle perçue à l’infertilité, des taux l

  8. Volvulus gastrique aigu sur éventration diaphragmatique de l'adulte: à propos d'un cas et revue de la littérature

    PubMed Central

    Guèye, Mohamadou Lamine; Touré, Alpha Oumar; Thiam, Ousmane; Seck, Mamadou; Cissé, Mamadou; Kâ, Ousmane; Dieng, Madieng; Touré, Cheikh Tidiane

    2015-01-01

    Le volvulus gastrique aigu sur éventration diaphragmatique est une affection rare et une urgence diagnostique et thérapeutique. Sa présentation clinique est peu spécifique et la tomodensitométrie abdominale permet de confirmer le diagnostic. Nous rapportons le cas d'un patient de 22 ans qui présentaitun syndrome occlusif et une voussure épigastrique. A la radiographie de l'Abdomen Sans Préparation, on notait 2 niveaux hydro-aériques sous la coupole diaphragmatique gauche qui était surélevée. Une dévolvulation et une gastrectomie atypique ont été réalisées devant un volvulus gastrique aigu avec nécrose du fundus mis en évidence à la laparotomie. Les suites opératoires ont été simples. PMID:26161223

  9. La prévention et la prise en charge de la douleur et du stress chez le nouveau-né

    PubMed Central

    2000-01-01

    Le présent énoncé est destiné aux professionnels de la santé qui s’occupent de nouveau-nés (prématurés ou à terme, jusqu’à un mois de vie). Il vise à sensibiliser les professionnels au fait que les nouveau-nés ressentent de la douleur, à fournir les assises physiologiques de la douleur néonatale ainsi que de l’examen et de la prise en charge du stress par les professionnels de la santé, à faire des recommandations pour réduire l’exposition des nouveau-nés aux stimulus nuisibles et pour réduire au minimum les résultats indésirables associés, ainsi qu’à recommander des interventions efficaces et sécuritaires qui soulagent la douleur et le stress.

  10. Traitement arthroscopique d'une fracture articulaire de la glène: nouvelle astuce

    PubMed Central

    Hamoudi, Samir; Alassaf, Ihab; Boussakri, Hassan; Ntrataze, Philbert; Dumez, Jean François

    2015-01-01

    Le traitement des fractures de la glène scapulaire constitue un sujet de débat dans la littérature. Les auteurs décrivent une observation d'un patient âgé de 22 ans qui présente une fracture articulaire de la glène classée stade III de Ideberg traitée chirurgicalement sous arthroscopie. Nous exposons une nouvelle technique chirurgicale utilisant un matériel simple et nous la recommandons pour ce type de fracture qui constitue une alternative efficace. Globalement, nos résultats cliniques et anatomiques immédiats et à moyen terme, au dernier recul, sont excellents. PMID:26161191

  11. Diffusion dans les liquides

    NASA Astrophysics Data System (ADS)

    Dianoux, A. J.

    2003-09-01

    Après une brève introduction qui rappelle les concepts détaillés dans le cours de M. Bée, nous présentons un aperçu de trois de nos travaux sur l'étude de la diffusion. Tout d'abord la dynamique de l'eau, dans son état normal ou surfondu, révèle la complexité apportée par le réseau de liaisons hydrogène. Ensuite l'effet du confinement sur la dynamique de l'eau sera étudié dans le cas de la membrane Nafion. Enfin la diffusion dans les phases nématique et smectique A d'un cristal liquide permet d'obtenir la valeur du potentiel qui maintient les couches dans la phase smectique.

  12. La matiere noire dans l'Univers.

    NASA Astrophysics Data System (ADS)

    Mamon, G.

    Parmi les mille questions que l'on peut se poser sur l'Univers, les plus fondamentales concernent son contenu : De quoi est faite la matière de l'Univers ? Est-ce que la matière de l'Univers est principalement constituée d'étoiles, ou bien de gaz interstellaire, de poussières interstellaires, de planètes, petits astéroïdes, ou de trous noirs ? Ou doit-on admettre que l'Univers est composé d'une autre forme de matière que l'on ne connaît pas, qui serait basée sur des particules élémentaires plus exotiques que les protons, neutrons et électrons qui constituent la matière ordinaire, dite baryonique?

  13. Voyage dans le noir. Trous noirs, matière noire, énergie noire et antimatière

    ScienceCinema

    None

    2016-07-12

    Et si nous faisions avec les physiciens un voyage dans le noir ? De l'astrophysique à la physique des particules les trois noirs, la matière noire, l'énergie noire ou l’antimatière intriguent et fascinent. Que sont ces objets qui bousculent nos idées et qui véhiculent parfois des craintes irraisonnées? Luis Alvarez-Gaume, Michael Doser et Christophe Grojean, physiciens du CERN vous invitent à mettre en lumière (!) les constituants de base de la matière et à explorer les mystères de la physique contemporaine. Une soirée lumineuse pour éclairer des concepts et ne plus avoir peur du noir.

  14. Meeting Jentschke

    ScienceCinema

    None

    2016-07-12

    Après une introduction des dernières recherches et nouvelles au Cern, le DG W.Jentschke parle du futur management du Cern avec deux nouv directeurs générales, responsables pour les 5 ans prochains: le Dr.J.B.Adams qui s'occupera de l'administration du Cern et aussi de la construction des bâtiments et équipements et Le Dr.L.van Hove qui sera responsable pour les activités de la recherche. Le DG parle des changes et structures prévus, des services communs, des différentes divisions et leurs chefs etc...

  15. Meeting Jentschke

    SciTech Connect

    2006-01-23

    Après une introduction des dernières recherches et nouvelles au Cern, le DG W.Jentschke parle du futur management du Cern avec deux nouv directeurs générales, responsables pour les 5 ans prochains: le Dr.J.B.Adams qui s'occupera de l'administration du Cern et aussi de la construction des bâtiments et équipements et Le Dr.L.van Hove qui sera responsable pour les activités de la recherche. Le DG parle des changes et structures prévus, des services communs, des différentes divisions et leurs chefs etc...

  16. Le fibromatosis colli ou torticolis congénital: son diagnostic et sa prise en charge à propos de deux cas

    PubMed Central

    Tchaou, Mazamaesso; Pegbessou, Plaodezina Essobozou; Sonhaye, Lantam; Ahouanssou, Patricia Yékpé; Amadou, Abdoulatif; Kolou, Beresa; Kama, Lidi Bessi; Garba, Nouhou Mahamadou; Koussema, Lama Kegdigoma Agoda; N'dakéna, Koffi

    2015-01-01

    Le fibromatosis colli (FC) est pseudotumeur rare du muscle sterno-cléido-mastoïdien (SCM), à l'origine d'un torticolis dit congénital chez le nouveau-né ou le nourrisson. Le mécanisme étio-pathogénique de sa survenue est sujet à controverse. Son diagnostic fait appel à l’échographie qui permet de mettre en évidence un épaississement caractéristique du muscle. Nous rapportons deux cas diagnostiqués par l’échographie avec pour un cas une notion de malposition intra-utérine et pour l'autre cas une absence totale de malposition et de traumatisme obstétrical qui pourtant est évoqué comme élément du mécanisme de survenue du FC. PMID:26834927

  17. Epilepsie révélant une chorée-acanthocytose: à propos d’un cas

    PubMed Central

    Doghmi, Nawfal; Elkoundi, Abdelghafour; Meskine, Amine; Benakrout, Aziz; Baite, Abdelouahed; Haimeur, Cherqui

    2016-01-01

    La chorée-acanthocytose (ChAc) est une affection autosomique récessive très rare causée par des mutations dans le gène VSP13A sur le chromosome 9q21. Elle est caractérisée par des signes neurologiques, des manifestations psychiatriques et une atteinte multisystémique comportant une myopathie, une neuropathie axonale et la présence de globules rouges spiculées ou acanthocytes. Rarement, l’épilepsie peut être le symptôme initial chez ces patients, ce qui peut considérablement retarder le diagnostic. Nous décrivons le cas d’un patient atteint de cette pathologie qui a présenté des crises épileptiques plusieurs années avant l’apparition des manifestations typiques. PMID:27795769

  18. Lipome du corps calleux: à propos d'un cas avec revue de littérature

    PubMed Central

    Zhari, Bouchra; Mattiche, Houda; Boumdine, Hassan; Amil, Touriya; Ennouali, Hassan

    2015-01-01

    Le lipome du corps calleux est une malformation congénitale très rare, qui peut être associée à des degrés divers de dysgénésie du corps calleux. Son extension dans le ventricule latéral est encore plus rare. Il est souvent asymptomatique, mais peut se présenter par une épilepsie, hémiplégie, démence ou de simples céphalées. La tomodensitométrie et l'imagerie par résonance magnétique permettent facilement le diagnostic. Nous rapportons le cas d'une jeune fille de 14 ans, souffrant de simples céphalées, chez qui on découvre un lipome du corps calleux avec extension au ventricule latéral. PMID:26526933

  19. Fracture isolée du petit trochanter chez l'adulte, et si c’était une métastase: à propos d'un cas et revue de la littérature

    PubMed Central

    Abid, Hatim; El Idrissi, Mohamed; Shimi, Mohamed; El Ibrahimi, Abdelhalim; El Mrini, Abdelmajid

    2013-01-01

    Nous rapportons dans ce travail le cas d'une fracture du petit trochanter sans notion de traumatisme survenue chez une patiente de 85 ans. Il s'agit d'une entité pathologique rare due à une infiltration tumorale de la région trochantérienne souvent de nature métastatique qui peut être méconnue initialement. C’était le cas de notre malade, qui s'est compliquée après 1 mois d’évolution d'une fracture sous trochantérienne. Notre prise en charge thérapeutique était à visée palliative devant des localisations métastatiques multiples. PMID:24772226

  20. Pelvic floor tenderness in the etiology of superficial dyspareunia.

    PubMed

    Yong, Paul J; Mui, Justin; Allaire, Catherine; Williams, Christina

    2014-11-01

    Objectif : Calculer la prévalence de la sensibilité du plancher pelvien au sein de la population des femmes qui connaissent des douleurs pelviennes et déterminer ses implications pour ce qui est des symptômes de la douleur pelvienne. Méthodes : Nous avons mené une analyse rétrospective auprès de patientes connaissant des douleurs pelviennes au sein d’un centre spécialisé tertiaire. La sensibilité du plancher pelvien a été définie comme étant une sensibilité du muscle releveur de l’anus ressentie au moins d’un côté au cours d’un examen pelvien mené au moyen d’un seul doigt. La prévalence de la sensibilité du plancher pelvien au sein de cette cohorte de femmes connaissant des douleurs pelviennes a été comparée à la même prévalence au sein d’une cohorte de femmes exemptes de douleurs fréquentant une clinique de gynécologie. Chez les femmes connaissant des douleurs pelviennes, une régression multiple a été menée en vue d’identifier les variables qui étaient associées de façon indépendante à la sensibilité du plancher pelvien. Résultats : La prévalence de la sensibilité du plancher pelvien était de 40 % (75/189) au sein de la cohorte « douleurs pelviennes »; elle était donc considérablement supérieure à la prévalence de 13 % (4/32) qui a été constatée au sein de la cohorte « absence de douleur » (RC, 4,61; IC à 95 %, 1,55 - 13,7, P = 0,005). Dans le cadre de la régression logistique multiple, la dyspareunie superficielle (RC, 4,45; IC à 95 %, 1,86 - 10,7, P = 0,001), la douleur ressentie au niveau de la paroi abdominale (RC, 4,04; IC à 95 %, 1,44 - 11,3, P = 0,005) et la sensibilité de la base de la vessie (RC, 4,65; IC à 95 %, 1,87 - 11,6, P = 0,001) étaient associées de façon indépendante à la sensibilité du plancher pelvien. Cette dernière était tout aussi présente chez les femmes qui connaissaient une endométriose sous-jacente que chez les femmes qui ne connaissaient

  1. Avortements non médicalisés: état des lieux à travers une étude rétrospective de 451 cas traités à l'hôpital militaire d'instruction Moulay Ismail Meknès, Maroc

    PubMed Central

    Laghzaoui, Omar

    2016-01-01

    L'avortement non médicalisé est un fléau dans le monde entier mais notamment en Afrique où il constitue un marché lucratif pour les tradipraticiens qui exposent les patientes à des complications graves voir mortelles. Notre étude rétrospective de 451 dossiers représente un échantillon exhaustif de cette pratique au Maroc soulevant les raisons qui poussent les femmes à l'avortement non médicalisé, la tranche d’âge la plus concernée, les conditions et les complications inhérentes à l'acte. Notre travail aboutit sur la nécessité d'intervenir avant la grossesse en développant la notion de contraception chez les jeunes filles dès la scolarité pour minimiser ces pratiques non sanitaires. PMID:27642422

  2. Lupus érythémateux systémique à début pédiatrique: à propos d'un cas

    PubMed Central

    Khlif, Sana; Hachicha, Hend; Frikha, Faten; Feki, Sawsan; Ben Ayed, Mourad; Bahloul, Zouhir; Masmoudi, Hatem

    2015-01-01

    Le lupus érythémateux systémique (LES) est une maladie systémique auto-immune d’étiologie inconnue qui touche essentiellement les femmes à l’âge adulte. Le lupus pédiatrique est une entité rare. Nous rapportons une nouvelle observation. Il s'agissait d'un nourrisson âgé de 7 mois qui présentait des lésions cutanées purpuriques, une polyarthrite fébrile. Le bilan immunologique était positif (AAN et anti-ADN). Une amélioration clinique et biologique a été notée sous corticothérapie générale avec une récidive lors de la dégression du traitement. PMID:26015845

  3. Kyste hydatique du foie: à propos d'un mode de révélation exceptionnel

    PubMed Central

    Eddeghai, Siham; Eddoukani, Imane; Diffaa, Azzedine; Krati, Khadija

    2014-01-01

    Le kyste hydatique (KH) est une maladie parasitaire bénigne qui touche avec prédilection le foie. Il est assez fréquent dans les pays du pourtour méditerranéen, cependant il reste une cause exceptionnelle d'hypertension portale. Nous rapportons une nouvelle observation d′un patient qui présente un kyste hydatique du foie révélé par une hémorragie digestive sur un syndrome d′hypertension portale en précisant ses différentes particularités diagnostiques et thérapeutiques avec une revue de littérature. PMID:25419296

  4. POEMS syndrome: un diagnostic à ne pas méconnaitre

    PubMed Central

    Mahfoudhi, Madiha; Turki, Sami; Kheder, Adel

    2015-01-01

    Le POEMS syndrome est une affection multi-viscérale rare qui peut s'accompagner de complications graves. Nous rapportons le cas d'un homme âgé de 48 ans qui avait une poly-neuropathie périphérique, une poly-adénopathie, des ongles blancs nacrés, une hypothyroïdie et une gammapathie monoclonale. L’évolution était marquée par l'aggravation des signes neuroloqiques. Des cures de thalidomide-dexaméthasone ont été administrées sans aucune amélioration clinique. Le patient était rapidement décédé. Le but de ce travail est d'insister sur le polymorphisme clinique et le pronostic variable de cette entité. PMID:26309480

  5. Ostéchondromatose synoviale de l'articulation carpo-métacarpienne du pouce chez une patiente atteinte d'un lupus érythémateux systémique

    PubMed Central

    Loukil, Hanen; Frikha, Faten; Snoussi, Mouna; Garbaa, Saida; Salah, Raida Ben; Bahloul, Zouhir

    2015-01-01

    L'ostéchondromatose synoviale est une métaplasie du tissu synovial. Elle engendre de petites masses cartilagineuses qui font saillie à la face interne de la synoviale, puis, se pédiculisent et enfin s'en détachent en développant des chondromes libres. On en distingue deux formes d'ostéchondromatose, la forme primitive, qui est rare, et la forme secondaire plus fréquente dont l'origine est généralement l'arthrose. Nous rapportons un cas d'ostéchondromatose synoviale de l'articulation carpo-métacarpienne du pouce chez une patiente atteinte d'un lupus érythémateux systémique. PMID:26918080

  6. Polyradiculonévrite inflammatoire démyélinisante chronique révélant une thrombocytémie essentielle

    PubMed Central

    Jaafoura, Neirouz Ghannouchi; Atig, Amira; Bouker, Ahmed; Alaoua, Omar; Khalifa, Mabrouk; Bahri, Fathi

    2014-01-01

    La polyradiculonévrite inflammatoire démyélinisante chronique est une affection rare qui se caractérise par une neuropathie sensitivo-motrice démyélinisante, segmentaire et multifocale de mécanisme probablement dys-immunitaire et répondant à un traitement immunomodulateur. Une étiologie sous jacente est retrouvée dans près de 40% des cas et peut être infectieuse, auto-immune ou tumorales que ce soit les néoplasies solides ou les hémopathies notamment les gammapathies monoclonales. Nous rapportons une association exceptionnelle de polyradiculonévrite inflammatoire démyélinisante chronique qui révèle une thrombocytémie essentielle. PMID:25722774

  7. Superconductivity and charge transfer excitations in high T c superconductors

    NASA Astrophysics Data System (ADS)

    Balseiro, C. A.; Alascio, B.; Gagliano, E.; Rojo, A.

    We present some numerical results to show that in a simple model which includes Cu3d and O 2p orbitals together with inter and intra atomic correlations pairing between holes can occur due to charge transfer excitations. We present also a simple approximation to derive an effective Hamiltonian containing an interaction between particles which is attractive for some values of the different microscopic parameters. Nous présentons des résultats numériques qui montrent que dans un modèle simple, incluant les orbitales 3d du cuivre et 2p de l'oxygène, avec une interaction coulombienne interatomique et intra-atomique, les trous peuvent s'apparier à cause des excitations de transfert de charge. Nous présentons aussi une approximation simple pour obtenir un Hamiltonien effectif contenant une interaction entre particules qui peut être attractive pour certaines valeurs des paramètres microscopiques.

  8. Geoffrey Burbidge : L'art de la critique

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1997-06-01

    Avec pres de cinquante ans de carriere derriere lui, Geoffrey Burbidge n'a rien perdu de son gout du débat et de la controverse. Mondialement reconnu pour ses travaux sur les quasars, il en agace aujourd'hui plus d'un en venant deranger le bel ordonnancement de la cosmologie. Il porte sur le monde scientifique un regard tres critique, condamnant notamment ces chercheurs qui acceptent trop volontiers d'emprunter les chemins tout traces.

  9. A Woman With Marfan Syndrome in Pregnancy: Managing High Vascular Risk With Multidisciplinary Care.

    PubMed

    Naud, Kentia; Horne, Gabrielle; Van den Hof, Michiel

    2015-08-01

    Contexte : Bien que les femmes qui présentent des troubles affectant les tissus conjonctifs soient exposées à des risques de complications cardiovasculaires pendant la grossesse, nous ne disposons d’aucune ligne directrice en ce qui concerne les femmes enceintes dont le diamètre de l’anneau aortique est supérieur à 45 mm ou qui connaissent un élargissement rapide de l’aorte. Nous décrivons les facteurs significatifs sur le plan pratique dans le cadre de la prise en charge de la grossesse et de l’accouchement chez une femme atteinte du syndrome de Marfan.  Cas : Une femme enceinte atteinte du syndrome de Marfan nous a consultés pour obtenir des soins tertiaires à 26 semaines de gestation. La dilatation rapide de l’aorte a mené à la décision de procéder à un accouchement préterme (lequel a donné lieu à une bonne issue néonatale). Le recours à une approche multidisciplinaire a contribué à l’optimisation du monitorage et de la chronologie de l’accouchement (et à la réparation subséquente de l’aorte), en plus de permettre la planification de la prise en charge d’une potentielle catastrophe vasculaire.  Conclusion : Dans le cas des femmes enceintes qui sont atteintes du syndrome de Marfan, l’obtention d’issues maternelles et néonatales optimales dépend de la mise en œuvre d’un effort d’équipe grandement attentif et coordonné (y compris celle d’une planification méticuleuse de la prise en charge d’une potentielle catastrophe vasculaire).

  10. Meeting DG's

    ScienceCinema

    None

    2016-07-12

    Le DG J.Adams commente les 3 thèmes de la réunion: 1.) le prochain DG du Cern (qui sera H.Schopper) 2.) le LEP 3.) les conclusions du comité des finances concernant salaires, allocations etc. Discussion entre le DG J.Adams, Mons.Ullmann, chef du personel et l'auditoire

  11. Etude RICH Nursing. Plus de connaissances et de preuves scientifiques

    PubMed Central

    SCHUBERT, MARIA

    2009-01-01

    L’importance et la validité des résultats de l’étude RICH-Nursing* ont été récemment mises en cause par certains milieux, ce qui a provoqué certaines incertitudes chez les infirmières. Les auteurs reviennent sur l’impact actuel de cette étude et évoquent les perspectives d’avenir. PMID:25221376

  12. The False Claims Act and clinical laboratories.

    PubMed

    Vogel, R L

    1993-01-01

    In its efforts to fight fraud, the government has turned increasingly to the civil False Claims Act. The Act imposes triple damages plus monetary penalties against those who defraud the federal government. The Act also encourages whistleblowers to report fraud by offering the prospect of large bounties. This article describes the False Claims Act, its qui tam provision dealing with whistleblowers, and the application of the Act to clinical laboratories.

  13. Big Rip : la grande déchirure

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    2007-10-01

    Le jour où l'Univers se dechirera. L'énergie sombre pourrait bien faire basculer le destin de l'Univers. Disloqué par cette force mystérieuse qui accélère son expansion, le cosmos finirait alors en un immense feu d'artifice. Emietté jusqu'au moindre de ses atomes !

  14. Sursauts gamma : nés de supernovae bien ordinaires

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    2003-10-01

    L'énigme de l'origine des sursauts gamma défiait les astrophysiciens depuis trente ans. La solution semble aujourd'hui évidente : ces flashes très énergétiques seraient issus de "banales" supernovae. Une avancée due au plus puissant sursaut jamais enregistré, le 29 mars dernier, qui rend subitement accessible l'étude des premières étoiles de l'Univers.

  15. APPOLLO 9

    ScienceCinema

    None

    2016-07-12

    le DG B.Grégory prend la parole et introduit le cosmonaute américain Russell Schweickart, qui fait un exposé sur la mission APPOLLO 9 et l'avenir de l'exploration spatiale avec présentation d'un film avec musique, mais sans parole, après commentaires et questions

  16. Capteurs monopodes pour mesures accélérométriques

    NASA Astrophysics Data System (ADS)

    Delaite, R.; Valentin, J.-P.

    1993-08-01

    A new design for accelerometric measurements sensors is described. It uses a plate vibrating in thickness shear mode, maintained by the means of a single holder located at the crystal edge. This mounting does cancel the mechanical and thermal stresses which generally modify the sensor output signal. So the ratio signal/noise of a thickness shear accelerometer is improved and the intrinsic sensitivity is multiplied by a factor 40, by comparison with the sensitivity of a thickness shear plate bonded by the means of two opposite holders. Un nouveau dispositif destiné aux mesures d'accélération est présenté. Il met en œuvre une lame vibrant en cisaillement d'épaisseur, fixée à sa structure de maintien par l'intermédiaire d'une unique liaison. Ce montage permet d'éliminer les contraintes mécaniques et thermiques qui perturbent habituellement le signal de mesure, et qui sont liées soit au montage des éléments du capteur, soit aux variations rapides de température qui interviennent lors de la mise en fonctionnement du capteur. Le rapport signal/bruit d'un accéléromètre à lame vibrant en cisaillement d'épaisseur s'en trouve amélioré et la sensibilité à l'accélération est multipliée par un facteur 40, comparée à celle d'un capteur qui serait constitué d'une lame vibrant en cisaillement d'épaisseur, fixée par deux liaisons diamétralement opposées.

  17. Cómo hacer las gestiones con su plan de salud

    Cancer.gov

    Hay formas de saber si su plan de salud cubre los costos de atención médica de rutina durante un estudio clínico. Esta información puede servirle para saber con quién comunicarse para solicitar ayuda, preguntas que puede hacer y la información que debe recoger y guardar si decide participar en un estudio clínico.

  18. On the Discovery of the Asteroid 3784 Chopin

    NASA Astrophysics Data System (ADS)

    Elst, E. W.

    Le 31 octobre 1986 lords d'une campagne de recherche d'asteroides a l'observatoire de Haute Provence, un asteroide de septieme magnitude fut decouvert. A l'occasion de l'opposition consecutive en 1988, l'asteroide fut observe a nouveau a l'observatoire de Haute Provence, ce qui entraina la numerotation definitive. L'asteroide recoit le numero 3874 et le nom du grand compositeur polonais, Chopin.

  19. Everest

    SciTech Connect

    2006-04-20

    Chris Bonington, est né à Hampstead et a fait des études à University Collège School à Londres et au Royal Military Academy à Sundhorst. Il est un alpiniste mondialement connu qui a fait un grand nombre de premiers ascensions, comme celle de la face sud-ouest de l'Everest avec une équipe de 70 hommes en septembre 1975

  20. A general purpose I{sub DDQ} measurement circuit

    SciTech Connect

    Wallquist, K.M.; Hawkins, C.F.; Righter, A.W.

    1993-11-01

    A relatively high-speed I{sub DDQ} measurement circuit called QuiC-Mon is described. Depending upon IC settling times, upper measurement rates range from 50 kHz to 250 kHz at 100 nA resolution. It provides an inexpensive solution for fast, sensitive I{sub DDQ} measurements in CMOS IC wafer probe or packaged part production testing.