Angular dependences in electroweak semi-inclusive leptoproduction

We present the leading order unpolarized and polarized cross sections in electroweak semi-inclusive deep inelastic leptoproduction. The azimuthal dependences in the cross section differential in the transverse momentum of the vector boson arise due to intrinsic transverse momenta of the quarks. However, the presented asymmetries are not suppressed by inverse powers of the hard scale. We discuss the different opportunities to measure specific asymmetries as offered by neutral compared to charged current processes and point out the optimal kinematical regions. The present and (proposed) future HERA collider experiments would be most suitable for measuring some of the asymmetries discussed here, especially in case of Lambda production.Comment: 10 pages, Revtex, 5 Postscript figures, uses aps.sty, epsfig.st

Spin structure and longitudinal polarization of hyperon in e+e- annihilation at high energies

Longitudinal polarizations of different kinds of hyperons produced in e+e- annihilation at LEP I and LEP II energies in different event samples are calculated using two different pictures for the spin structure of hyperon: that drawn from polarized deep inelastic lepton-nucleon scattering data or that using SU(6) symmetric wave functions. The result shows that measurements of such polarizations should provide useful information to the question of which picture is more suitable in describing the spin effects in the fragmentation processes.Comment: 26 pages with 10 figures. Submitted to Phys. Rev.

Spin alignment of vector meson in e+e- annihilation at Z0 pole

We calculate the spin density matrix of the vector meson produced in e+e- annihilation at Z^0 pole. We show that the data imply a significant polarization for the antiquark which is created in the fragmentation process of the polarized initial quark and combines with the fragmenting quark to form the vector meson. The direction of polarization is opposite to that of the fragmenting quark and the magnitude is of the order of 0.5. A qualitative explanation of this result based on the LUND string fragmentation model is given.Comment: 15 pages, 2 fgiures; submitted to Phys. Rev.

Systematic analysis of the polyphenol metabolome using the Phenol-Explorer database

SCOPE: The Phenol-Explorer web database details 383 polyphenol metabolites identified in human and animal biofluids from 221 publications. Here we exploit these data to characterize and visualize the polyphenol metabolome, the set of all metabolites derived from phenolic food components. METHODS AND RESULTS: Qualitative and quantitative data on 383 polyphenol metabolites as described in 424 human and animal intervention studies were systematically analyzed. Of these metabolites, 301 were identified without prior enzymatic hydrolysis of biofluids, and included glucuronide and sulfate esters, glycosides, aglycones, and O-methyl ethers. Around one third of these compounds are also known as food constituents and corresponded to polyphenols absorbed without further metabolism. Many ring-cleavage metabolites formed by gut microbiota were noted, mostly derived from hydroxycinnamates, flavanols and flavonols. Median maximum plasma concentrations (Cmax ) of all human metabolites were 0.09 μM and 0.32 μM when consumed from foods or dietary supplements respectively. Median time to reach maximum plasma concentration in humans (Tmax ) was 2.18 h. CONCLUSION: These data show the complexity of the polyphenol metabolome and the need to take into account biotransformations to understand in vivo bioactivities and the role of dietary polyphenols in health and disease. This article is protected by copyright. All rights reserved

Problématique D’Evacuation Des Déchets Ménagers Dans La Cite De Bumba: « Cas Du Quartier Nzongo : Du 1er Janvier Au 30 Avril 2019 »

face aux impacts négatifs des déchets ménagers sur la qualité de l’environnement et sur la santé publique ; la gestion durable des déchets ménagers est devenue un sujet d’actualité et nombreuses études y menées mettent en évidence divers risques environnementaux et sanitaires pour les populations le quartier Nzongo, notre milieu d’étude dans la cité de Bumba abandonne ses déchets ménagers sur des terrains vagues et dans des trous se trouvant dans les habitations. L’insalubrité constatée dans ce quartier avec des conséquences négatives sur la santé de la population a attiré notre attention afin de traiter de la problématique d’évacuation des déchets ménagers dans la cité de Bumba ; cas du quartier Nzongo

Les Albinos Face Au Développement Economique Du Territoire De Bumba « Cas De La Cité De Bumba »

l’albinisme est une affection autosomique récessive due à l’absence de mélanine dans  la peau, les  cheveux et les jeux. Les gens qui souffrent   de cette affection sont des albinos, souvent victimes des sacrifices humains d’assassinat voire d’enlèvement pour des fins magiques.  Etant marginalisés, leurs capacités restent inexploitées dans le menu du développement leur identification intégration  et leur promotion éducative seraient  des pistes de sortie du comportement  discriminatoire  leur affiché  afin d’atteindre  les  objectifs  du  millénaire  pour le développement  qui stipule « amélioration  de la santé  sous toutes ces formes  et  réduire par  conséquent ; l’extrême pauvreté »

Structure and Function of a Mycobacterial NHEJ DNA Repair Polymerase

Non homologous end-joining (NHEJ)-mediated repair of DNA double-strand breaks in prokaryotes requires Ku and a specific multidomain DNA ligase (LigD). We present crystal structures of the primase/polymerisation domain (PolDom) of Mycobacterium tuberculosis LigD, alone and complexed with nucleotides. The PolDom structure combines the general fold of the archaeo-eukaryotic primase (AEP) superfamily with additional loops and domains that together form a deep cleft on the surface, likely used for DNA binding. Enzymatic analysis indicates that the PolDom of LigD, even in the absence of accessory domains and Ku proteins, has the potential to recognise DNA end-joining intermediates. Strikingly, one of the main signals for the specific and efficient binding of PolDom to DNA is the presence of a 5'-phosphate group, located at the single/double-stranded junction at both gapped and 3'-protruding DNA molecules. Although structurally unrelated, Pol lambda and Pol mu, the two eukaryotic DNA polymerases involved in NHEJ, are endowed with a similar capacity to bind a 5'-phosphate group. Other properties that are beneficial for NHEJ, such as the ability to generate template distortions and realignments of the primer, displayed by Pol lambda and Pol mu, are shared by the PolDom of bacterial LigD. In addition, PolDom can perform non-mutagenic translesion synthesis on termini containing modified bases. Significantly, ribonucleotide insertion appears to be a recurrent theme associated with NHEJ, maximised in this case by the deployment of a dedicated primase, although its in vivo relevance is unknown

Phenol-Explorer 2.0: a major update of the Phenol-Explorer database integrating data on polyphenol metabolism and pharmacokinetics in humans and experimental animals

Phenol-Explorer, launched in 2009, is the only comprehensive web-based database on the content in foods of polyphenols, a major class of food bioactives that receive considerable attention due to their role in the prevention of diseases. Polyphenols are rarely absorbed and excreted in their ingested forms, but extensively metabolized in the body, and until now, no database has allowed the recall of identities and concentrations of polyphenol metabolites in biofluids after the consumption of polyphenol-rich sources. Knowledge of these metabolites is essential in the planning of experiments whose aim is to elucidate the effects of polyphenols on health. Release 2.0 is the first major update of the database, allowing the rapid retrieval of data on the biotransformations and pharmacokinetics of dietary polyphenols. Data on 375 polyphenol metabolites identified in urine and plasma were collected from 236 peer-reviewed publications on polyphenol metabolism in humans and experimental animals and added to the database by means of an extended relational design. Pharmacokinetic parameters have been collected and can be retrieved in both tabular and graphical form. The web interface has been enhanced and now allows the filtering of information according to various criteria. Phenol-Explorer 2.0, which will be periodically updated, should prove to be an even more useful and capable resource for polyphenol scientists because bioactivities and health effects of polyphenols are dependent on the nature and concentrations of metabolites reaching the target tissues. The Phenol-Explorer database is publicly available and can be found online at http://www.phenol-explorer.eu. Database URL: http://www.phenol-explorer.eu

Biomarkers of intake for coffee, tea and sweetened beverages

Non-alcoholic beverages are important sources of nutrients and bioactive compounds that may influence human health and increase or decrease the risk of chronic diseases. A wide variety of beverage constituents are absorbed in the gut, found in the systemic circulation and excreted in urine. They may be used as compliance markers in intervention studies or as biomarkers of intake to improve measurements of beverage consumption in cohort studies and reveal new associations with disease outcomes that may have been overlooked when using dietary questionnaires. Here, biomarkers of intake of some major non-alcoholic beverages coffee, tea, sugar-sweetened beverages, and low-calorie-sweetened beverages are reviewed. Results from dietary intervention studies and observational studies are reviewed and analyzed, and respective strengths and weaknesses of the various identified biomarkers discussed. A variety of compounds derived from phenolic acids, alkaloids, and terpenes were shown to be associated with coffee intake and trigonelline and cyclo(isoleucylprolyl) showed a particularly high specificity for coffee intake. Epigallocatechin and 4′-O-methylepigallocatechin appear to be the most sensitive and specific biomarkers for green or black tea, while 4-O-methylgallic acid may be used to assess black tea consumption. Intake of sugar-sweetened beverages has been assessed through the measurement of carbon-13 enrichment of whole blood or of blood alanine in North America where sugar from sugarcane or corn is used as a main ingredient. The most useful biomarkers for low-calorie-sweetened beverages are the low-calorie sweeteners themselves. Further studies are needed to validate these biomarkers in larger and independent populations and to further evaluate their specificity, reproducibility over time, and fields of application