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  • Open Access
    Authors: 
    Massimo Nespolo; Bernd Souvignier;
    Countries: Netherlands, France

    International audience; Author(s) of this paper may load this reprint on their own web site or institutional repository provided that this cover page is retained. Republication of this article or its storage in electronic databases other than as specified above is not permitted without prior permission in writing from the IUCr. For further information see http://journals.iucr.org/services/authorrights.html Many research topics in condensed matter research, materials science and the life sciences make use of crystallographic methods to study crystalline and non-crystalline matter with neutrons, X-rays and electrons. Articles published in the Journal of Applied Crystallography focus on these methods and their use in identifying structural and diffusion-controlled phase transformations, structure–property relationships, structural changes of defects, interfaces and surfaces, etc. Developments of instrumentation and crystallographic apparatus, theory and interpretation, numerical analysis and other related subjects are also covered. The journal is the primary place where crystallographic computer program information is published.

  • Open Access
    Authors: 
    Abelardo Bento Araújo;
    Publisher: Pro Reitoria de Pesquisa, Pos Graduacao e Inovacao - UFF

    Com base na economia política, este artigo traz uma discussão teórica sobre as especificidades do trabalho educativo, tendo em vista os problemas de compreensão do que seja seu produto. Colocam-se em pauta as consequências do monitoramento da qualidade da educação, quando esse conjunto de políticas pretende tornar avaliável o trabalho educativo por meio de escores de rendimento em testes em larga escala.

  • Open Access English
    Authors: 
    Hicham Jabraoui; Etienne Paul Hessou; Siwar Chibani; Laurent Cantrel; Sébastien Lebègue; Michael Badawi;
    Publisher: HAL CCSD
    Country: France

    International audience; The ability of Ag-exchanged mordenite (Ag-MOR)to capture iodine species such as I2 and CH3I as released for instance during a nuclear accident could be severely limited by the presence of volatile organic compounds (VOCs)that can disrupt their adsorption in the zeolite. Here, using density functional theory (DFT), we investigate in detail the adsorption process of several hydrocarbons (methane, cyclohexane, benzene, and 1,3-dimethylbenzene)and oxygenated compounds (methanol, ethanol, propan-2-ol and propanone)and compare it with the adsorption of I2 and CH3I for different values of the Si/Al ratio of the Ag-exchanged mordenite. It is found that the adsorption process of the iodine species becomes favorable as the Si/Al ratio is decreased. Indeed at high Si/Al ratio, some VOCs such as benzene, 1, 3-dimethylbenzene and propan-2-ol exhibit strong inhibiting effects, while at low Si/Al ratio, only the adsorption of CH3I is limited by the presence of aromatic hydrocarbons. Also, in addition to the elongation of the I[sbnd]I bond upon the adsorption of the iodine molecule in Ag-MOR with a high silver content, we found that there is a significant electron transfer between the Ag and I atoms. Thus, our results indicate that the I[sbnd]I bond becomes weaker during the adsorption and therefore the formation of AgI precipitates is favored. © 2019 Elsevier B.V.

  • Open Access English
    Authors: 
    Anthony F. Jorm; Angela Nicholas; Jane Pirkis; Alyssia Rossetto; Nicola J. Reavley;
    Publisher: BMC

    Background When a person is in severe distress, people in their social network can potentially take action to reduce the person’s suicide risk. The present study used data from a community survey to examine whether people who had received training in how to assist a person at risk of suicide had higher quality intentions and actions to provide support. Methods A national telephone survey was carried out with 3002 Australian adults on attitudes and intentions toward helping someone in severe distress or at risk of suicide as well as actions taken. Participants were asked about their intentions to assist a hypothetical person in a vignette and about any actions they took to assist a family member or friend in distress over the previous 12 months. Participants were also asked whether they had received professional training, Mental Health First Aid training or other training in how to assist a person at risk of suicide. Results Responses covered ten intentions/actions that were recommended in guidelines for the public on how to support a suicidal person and 5 that were recommended against in the guidelines. Scales were created to measure positive and negative intentions to act and positive and negative actions taken. All three types of training were associated with greater positive intentions and actions, and with lesser negative intentions. These associations were largely due to a greater willingness of those trained to talk openly about suicide with a person in distress. Conclusions Training in how to support a person at risk of suicide is associated with better quality of support. Such training merits wider dissemination in the community. Electronic supplementary material The online version of this article (10.1186/s12888-018-1722-y) contains supplementary material, which is available to authorized users.

  • Open Access
    Authors: 
    G. Muñoz; Cristina Óvilo; Jordi Estellé; Luis Silió; Almudena Fernández; Carmen Rodríguez;
    Publisher: Springer Science and Business Media LLC
    Countries: France, Spain

    Abstract The objective of this study was to search for polymorphisms in the coding region of the estrogen receptors 1 and 2 (ESR1 and ESR2 )and to analyze the effects of these variants and the well known intronic ESR1 Pvu II polymorphism on litter size in a Chinese-European pig line. We identified five silent single nucleotide polymorphisms (SNP) in the ESR1 cDNA: c.669T > C (exon 3), c.1227C > T (exon 5), c.1452C > T (exon 7), c.1665T > C and c.1755A > G (exon 8). One pair of these SNP (c.1665T > C and c.1755A > G) co-segregated in the analyzed line, and the SNP c.669T > C showed the same segregation pattern as the Pvu II polymorphism. These polymorphisms were tested in this study, although the c.1452C > T SNP within exon 7 was not analyzed due to its low informativeness. In the ESR2 cDNA, one missense SNP was found within exon 5, which caused an amino acid substitution in the coded protein: "c.949G > A (p.Val317Met)" and was tested on sow litter size. Information on 1622 litter records from 408 genotyped sows was analyzed to determine whether these SNP influenced the total number of piglets born (TNB) or the number of born alive (NBA). The polymorphisms ESR1: [Pvu II; c.669T > C], ESR1: [c.1665T > C; c.1755A > G] and ESR2: c.949G > A showed no statistically significant association with litter size. However, the ESR1: c.1227T allele was significantly associated with TNB. The additive substitution effect was estimated to be 0.40 piglets born per litter (P < 0.03), and no dominance effects were observed. This SNP could be useful in assisted selection for litter size in some pig lines, as a new genetic marker in linkage disequilibrium with the causative mutation.

  • Authors: 
    Céline Poncet-Legrand;
    Country: France

    Pourquoi s’intéresser aux colloïdes et macromolécules en œnologie ?

  • Closed Access English
    Authors: 
    Nadège Arnal; Claude Alban; Martine Quadrado; Olivier Grandjean; Hakim Mireau;
    Publisher: HAL CCSD
    Country: France

    Mitochondria are involved in the production of various vitamins, such as biotin, in plants. It is unclear why these biosynthetic pathways have been maintained partly or entirely within the mitochondria throughout evolution. The last step in biotin biosynthesis occurs within the mitochondria and is catalyzed by the biotin synthase complex containing the BIO2 gene product. We investigated whether the Arabidopsis Bio2 enzyme could function outside mitochondria, by trying to complement a bio2 mutant with a truncated version of BIO2 lacking the region encoding the mitochondrial targeting sequence. We describe the characterization of a new T-DNA allele of bio2, with the sole phenotype of an absence of biotin production, in contrast to the previously characterized EMS bio2 allele (Patton et al. 1998, Plant Physiol 116(3):935–946). We found that a cytosolic version of the Bio2 protein could not complement this mutant. Supplementation with the substrate dethiobiotin (DTB) also failed to rescue the mutant phenotype. Thus, the lack of availability of DTB in the cytosol is not the only factor preventing this reaction from occurring outside mitochondria. Bio2 requires mitochondrial targeting for activity, enabling it to fulfill its role in biotin synthesis. The reaction catalyzed by Bio2 may be subject to biochemical constraints, and the apparent close connection with the mitochondrial Fe-S machinery may account for the reaction being retained within the organelle.

  • Publication . Conference object . Article . 2021
    Open Access English
    Authors: 
    A. Adil; Ibrahima N'Doye; Ali Zemouche; Abdelghani Hamaz; Taous-Meriem Laleg-Kirati;
    Publisher: HAL CCSD
    Country: France

    Published in IFAC-PapersOnLine, 54(14):96:101, 2021; International audience; The coupled tanks system is a widely used nonlinear system for testing control and estimation methods. This system has various applications such as wastewater treatment, water desalination, pharmaceutical industries, and petrochemical plants. Among the challenging problems is the water level estimation which is needed for controlling the system. In this paper, a high-gain like observer is proposed for the estimation of the water level from delayed output measurement. This observer tolerates a larger bound of the time-delay compared to that obtained by using standard high-gain approach. We show the effectiveness of such observer design and how the standard approach fails to reconstruct the water level in the tanks in the presence of a larger bound on the time-delay.

  • Closed Access English
    Authors: 
    Nesrine Ben Yahmed; Hélène Carrère; M. Nejib Marzouki; Issam Smaali;
    Publisher: HAL CCSD
    Country: France

    Abstract The green macroalgal biomass corresponds to an emerging and promising biofuel feedstock. Their biological pretreatment and energetic conversion to biomethane were investigated and the enhancement of biogas production using the solid-state fermentation (SSF) as an eco-friendly innovative pretreatment of Ulva sp. was precisely assessed. Compared to conventional acid and alkali pretreatments, the highest methane potential of 153 ± 3 mL CH 4 g − 1 VS with an anaerobic biodegradability of 57% was obtained using SSF pretreatment with a locally isolated Aspergillus fumigatus SL1 strain. It was 132 ± 2 mL CH 4 g − 1 VS for raw Ulva sp. with biodegradability of 49%. Acid pretreatment with 4% HCl at 150 °C had a negative effect on Ulva sp.'s methane potential while alkali pretreatment with 4% NaOH at 20 °C showed a significant effect. The proposed SSF-based pretreatment enhanced therefore biogas production of 21% and permitted an eco-friendly valorization of large amounts of abundant macroalgae.

  • Open Access English
    Authors: 
    Wera Teubner; Walter Meinl; Simone Florian; Michael Kretzschmar; Hansruedi Glatt;
    Publisher: Portland Press Ltd.

    Soluble SULTs (sulfotransferases) are important in the regulation of messenger molecules and the elimination of xenobiotics. However, sulfo-conjugation of various substrates can also lead to the formation of reactive metabolites that may induce cancer and cause other damage. The aim of the present study was to identify the SULT forms expressed in the human gastrointestinal tract, especially the colon and rectum (common sites for cancer), and to determine their cellular localization. Normal colonic or rectal tissue, resected with tumours, was obtained from 39 subjects. For comparison, we additionally studied one to four samples from stomach, jejunum, ileum, cecum and liver. SULTs were detected by immunoblotting, immunohistochemistry and measurement of enzyme activities. SULT1A1, 1A3 and 1B1 were found in all parts of the gastrointestinal tract, often exceeding levels in liver (where these forms were present at high, undetectable and low levels respectively). They were predominantly localized in differentiated enterocytes. SULT1E1 and 2A1 were only detected in liver, jejunum, ileum and cecum. SULT1C1 was readily found in stomach, but was negligible elsewhere. SULT1A2 was present at low levels in individual samples. The remaining forms were not detected with the limitation that only high levels could be recognized with the antisera used. In conclusion, SULTs are abundant in the gastrointestinal tract of man. We suspect that they are involved in the presystemic elimination of bioactive food-borne components, including aglycones released by gut microbiota, as well as the bioactivation of some procarcinogens.

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