Miracle-dz/UniFAR-FTUs huggingface dataset:
An overview of the LEAR (Lobster Ecology and Recruitment) project: results of field and experimental studies on the juvenile ecology of Homarus gammarus in cobble

Field and experimental studies were undertaken in four European countries on clawed lobster (Homarus gammarus) ecology and recruitment. The aims were to assess: (a) abundance of early benthic phase (EBP) lobsters and other benthic species at cobble sites, (b) the effect of these species on EBP growth and survival, and (c) influence of these factors on recruitment and/or viability of restocking. Suction sampling of cobble sites revealed a wide diversity and abundance of potential competitors but no EBP lobsters. Hatchery-produced EBPs were therefore used for small-scale mesocosm experiments. In nature, predation on EBP was rapid without shelter, whereas in-vitro mortality, growth, and behaviour experiments showed that cover potentially increases survival. Scarcity per se may not completely explain the apparently absence of EBP, given that not a single EBP lobster was located either during this study or during any other of the extensive benthic investigations. The present paper discusses the implications of their apparent absence and whether it arises because EBPs are very scarce, cannot be captured by suction sampling, are not within lobster habitat, or occupy a specialized niche within adult habitat outside the range of current sampling methods.
Structural biology of viruses

Roger M. Burnett and Wah Chiu: Introduction. 1: Sherwood Casjens: Principles of Virion Structure, Function and Assembly. 2: Timothy S. Baker and John E. Johnson: Principles of Virus Structure Determination. 3: Judith M. White, et al.: Attachment and Entry of Influenza Virus Into Host Cells: Pivotal Roles of the Hernagglutin. 4: Michael G. Rossman, et al.: Rhinovirus Attachment and Cell Entry. 5: Thomas J. Smith and Anne G. Mosser: Antibody Mediated Neutralization of Picornaviruses. 6: Marie Chow, Ravi Basavappa and James M. Hogle: The Role of Conformational Transitions in Poliovirus Pathogenesis. 7: Robert L. Garcea and Robert C. Liddington: Structural Biology of Polyomaviruses. 8: Roger M. Burnett: The Structure of Adenovirus. 9: B.V. V. Prasad and Mary K. Estes: Molecular Basis of Rotavirus Replication: Structure-Function Correlations. 10: John E. Johnson and Roland R. Rueckert: Packaging and Release of the Viral Genome. 11: Johnathan King and Wah Chiu: The Procapsid to Capsid Transition in Double-Stranded DNA Bacteriophages. 12: Alasdair C. Steven and Patricia G. Spear: Herpesvirus Capsid Assembly and Envelopment. 13: Lee Makowski and Marjorie Russel: Structure and Assembly of Filamentous Bacteriophages. 14: Robert Weldon, Jr. and Eric Hunter: Molecular Requirements for Retrovirus Assembly. 15: Gillian M. Air and Ming Luo: Structure-Guided Therapeutic Strategies: General Overview. 16: Guy D. Diana, Mark A. McKinlay and Adi Treasurywala: The Use of Structural Information in the Design of Picornavirus Capsid Binding Agents. 17: C. Nicholas Hodge, et al.: Rational Design of HIV Protease Inhibitors
Manipulation of the ubiquitin-proteasome system by HIV-1 : role of the accessory protein Vpr

Human immunodeficiency virus 1 (HIV-1), the etiologic agent of AIDS, is a complex retrovirus with several accessory proteins. HIV-1 accessory proteins Nef, Vif, Vpr, and Vpu have been implicated in the modulation of viral replication, enhancement of viral fitness, immune evasion, and progression of AIDS pathogenesis. In that regard, viral protein R (Vpr) induces a cell cycle arrest in the G2 phase by activating the canonical ATR (Ataxia telangiectasia and Rad3 related)-mediated DNA damage checkpoint, but cellular factors and mechanisms directly engaged in this process remain unknown. To identify novel Vpr-interacting cellular factors, we used tandem affinity purification (TAP) to isolate native Vpr-containing complexes. We found that Vpr hijacks a cellular E3 ubiquitin ligase complex, CRL4A(VprBP), composed of Cullin 4A, DDB1 (DNA damage-binding protein 1) and VprBP (Vpr-binding protein). Moreover, we observed that recruitment of the E3 ligase by Vpr was necessary but not sufficient for the induction of G2 cell cycle arrest, suggesting that additional events are involved. In this context, we provide direct evidence that Vpr usurps the function of CRL4A(VprBP) to induce the K48-linked polyubiquitination and proteasomal degradation of as-yet-unknown cellular proteins. These ubiquitination events mediated by Vpr were necessary for the activation of ATR. Moreover, we show that Vpr forms chromatin-associated foci that co-localize with VprBP and DNA repair factors. Our data indicate that formation of these foci represent a critical early event in the induction of G2 arrest. Finally, we show that Vpr is able to recruit CRL4A(VprBP) on chromatin and we provide evidence that the unknown substrate targeted by Vpr is a chromatinassociated protein.
Target site DNA recognition by Tn3 and Sin resolvases

This work examined the DNA-recognition and synapsis capabilities of Sin and Tn3 resolvases, by alteration of regions of the protein to determine their significance for resolvase function. The importance of the E-helix (an -helical structure in the centre of the resolvase, connecting the catalytic domain and DNA-binding domain of the protein) of Sin recombinase, for DNA recognition at the centre of res site I, and for the formation of a synaptic tetramer was investigated. It was observed that swapping of the E-helix ‘arm’ region from Sin residues to the equivalent residues from Tn3resolvase abolished formation of the synapse. Truncated variants of Sin with the catalytic domain removed, termed ‘tadpoles’, were compared with a full-length activated mutant of Sin (Q115R) to determine the importance of the E-helices in formation of the synapse. From the ‘tadpole’ constructs, it was determined that the E-helix region between residues 109 and 124 is required for the formation of synaptic complexes, as deletion of this region was observed to abolish formation of the complex in vitro. Structure-guided single-residue mutations in this region of the E-helix further demonstrated that residues L112, I116 and M119, which are located on the flat hydrophobic interface between the E-helices of the Sin subunits in the synaptic tetramer complex, have a key role in the formation of this complex. Mutation of any of these residues to an alanine, both in the truncated Sin variants with a wildtype background and in the full-length activated mutant Q115R blocks formation of this complex. The truncated versions of Sin support the hypothesis that a bundle offour E–helices comprises a basic synapsis-competent module. In a related project, transcription activator-like effector recombinases (TALERs), chimeric constructs were constructed with the catalytic domain of an activated variant of Tn3 resolvase (NM) fused to the DNA binding domain of a TALE protein, TALERs with different N-terminal TALE truncations were constructed. It was demonstrated that the TALER constructs were successfully targeted to designed cognate ‘T-sites’, utilising the DNA-binding specificity of the TALE domain. It was also demonstrated that some of the TALERs constructed are able to catalyse cleavage at T-sites in vitro.
Phylogenetic position of Dendropsophus gaucheri (Lescure and Marty 2000) highlights the need for an in-depth investigation of the phylogenetic relationships of Dendropsophus (Anura: Hylidae)

Dendropsophus gaucheri is a recently described species which inhabits open areas of the eastern part of the Guiana Shield and is currently assigned to the D. parviceps species group based on the presence of a subocular cream spot. Herein we investigate its phylogenetic position including material from the type locality and newly documented populations from Suriname and Brazil based on mtDNA sequences. The species, as well as D. riveroi which is assigned to the D. minimus species group, were recovered nested within the D. microcephalus species group which implies the paraphyly of the three Dendropsophus species groups. Such result, along with other evidences, highlights the need for a thorough revision of the genus. The genetic distances among D. gaucheri samples studied are low confirming their conspecificity and suggesting recent connections among populations from open areas currently isolated by rainforest in the lowlands of the Guiana Shield.
The coevolution of gene mobility and sociality in bacteria

Bacteria are social organisms which participate in multiple cooperative and group behaviours. They moreover have peculiar genetic systems, as they often bear mobile genetic elements like plasmids, molecular symbionts that are the cause of widespread horizontal gene transfer and play a large role in bacterial evolution. Both cooperation and horizontal transfer have consequences for human health: cooperative behaviours are very often involved in the virulence of pathogens, and horizontal gene transfer leads to the spread of antibiotic resistance. The evolution of plasmid transfer has mainly been analyzed in terms of infectious benefits for selfish mobile elements. However, chromosomal genes can also modulate horizontal transfer. A huge diversity in transfer rates is observed among bacterial isolates, suggesting a complex co-evolution between plasmids and hosts. Moreover, plasmids are enriched in genes involved in social behaviours, and so could play a key role in bacterial cooperative behaviours. We study here the coevolution of gene mobility and sociality in bacteria. To investigate the selective pressures acting on plasmid transfer and public good production, we use both mathematical modelling and a synthetic system that we constructed where we can independently control public good cooperation and plasmid conjugation in Escherichia coli. We first show experimentally that horizontal transfer allows the specific maintenance of public good alleles in a structured population by increasing relatedness at the gene-level. We further demonstrate experimentally and theoretically that this in turn allows for second-order selection of transfer ability: when cooperation is needed, alleles promoting donor and recipient abilities for public good traits can be selected both on the plasmid and on the chromosome in structured populations. Moreover, donor ability for private good traits can also be selected on the chromosome, provided that transfer happens towards kin. The interactions between transfer and cooperation can finally lead to an association between transfer and public good production alleles, explaining the high frequency of genes related to cooperation that are located on plasmids. Globally, these results provide insight into the mechanisms maintaining cooperation in bacteria, and may suggest ways to target cooperative virulence.
Salinity tolerance of some bivalves of Ennore estuary

The clam Meretrix meretrix, the green mussel Perna viridis and the oyster Crassostrea madrasensis exist in the Ennore Estuary. The ' bar' is open throughout the year and as a result except during the Northeast Monsoon period when there is significant fall in salinity, higher salinity as in the inshore waters are prevalent. The present investigations were designed and aimed at studying the salinity tolerance of the above mentioned bivalves. In the experiments conducted they were subjected to a series of salinity changes ranging from 0 to 35 %„. The rates of mortality of the animals in different salinity media were noted at the end of 24 hours for a consecutive period of ten days. It was found that the bivalves were tolerant to the salinity change of the experimental media when the survival rate was 50% and above at the close of this period. The results obtained show that Crassostrea madrasensis, Meretrix meretrix and Perm viridis can tolerate an approximate low salinity of 7, 13 and 16%, respectively under laboratory conditions.
Sistema para la generación personalizada de resúmenes a partir de múltiples documentos

Nowadays the information needs are constantly increasing and at the same time they are very diverse, this last due to the presence of users with different profiles. During the last decade the increase in content generation has grown so much that it requires a great amount of resources for storing and accurately processing all this information. This explosion of information requires the development of intelligent
Les cellules initiatrices de tumeurs à l'origine de l'hétérogénéité d'expression de l'intégrine α5β1 dans les glioblastomes

Le glioblastome (GBM) est la tumeur cerebrale la plus agressive. L’echec therapeutique s’explique par son caractere heterogene. Nous etudions l’integrine α5β1, le recepteur de la fibronectine, dont les travaux du laboratoire ont montre l'implication dans l’agressivite du GBM. Il a ete observe que l’expression de l’integrine α5 est heterogene entre patients et au sein d’une meme tumeur. Nous avons emis l’hypothese que cette heterogeneite peut etre expliquee par l’existence de differentes cellules souches de GBM (CSGs). Nos travaux montrent que certaines CSGs expriment l’integrine apres differentiation, demontrant une heterogeneite intertumorale. Une expression heterogene a egalement ete mise en evidence au sein d’une meme lignee, indiquant une heterogeneite intratumorale. Nos resultats demontrent que les CSGs programmees a exprimer l’integrine forment des cellules differenciees agressives. Nos donnees montrent que l’integrine α5 est impliquee dans l’expansion tumorale mais aussi dans la survie et la migration en presence de fibronectine. Ce travail permet de mieux comprendre l’origine de foyers plus agressifs et souligne l’interet de l’integrine α5β1 comme cible therapeutique pour une sous-population de patients.
Physiology, NMDA Receptor

The N-methyl-D-aspartate (NMDA) receptor is a ligand of glutamate, the primary excitatory neurotransmitter in the human brain. It plays an integral role in synaptic plasticity, which is a neuronal mechanism believed to be the basis of memory formation. NMDA receptors also appear to have involvement in a process called excitotoxicity. Excitotoxicity may play a role in the pathophysiology of a variety of diseases such as epilepsy or Alzheimer disease. Many drugs inhibit NMDA receptors, including ketamine and phencyclidine, two common drugs of abuse.
Safening effects of 1,8-naphthalic anhydride in corn plants treated with bensulfuron-methyl and imazaquin

除草剤, bensulfuron-methyl [BEN; methyl-2-[[[[{(4,6-dimethoxy-2-pyrimidinyl)amino}carbonyl]amino]sulfonyl]-methyl]benzoic acid] および imazaquin [IMA; 2-{4,5-dihydro-4-methyl-4-(1-methyl ethyl)-5-oxo-1H-imidazol-2-yl}-3-quinolinecarboxylic acid] を処理したトウモロコシ (Zea mays L.) における, 1,8-naphthalic anhydride (NA) の薬害軽減作用を調べた. NAを処理したトウモロコシはBENあるいはIMAに対してそれぞれ10.2と5. 1の薬害軽減効果指数 (safening index) を示し, 0.2% (w/w) 濃度のNAを種子粉依処理した場合がもっとも効果的であった. またトウモロコシ生長初期に除草剤を処理した場合, NAによる薬害軽減効果が増加する傾向を示した. NAはトウモロコシ組織の acetolactate synthase (ALS) と acetyl CoA carboxylase (ACCase) の活性をそれぞれ32%と216%増加させた. しかし, in vitro 実験では, これらの両除草剤はNA処理または無処理のトウモロコシの ACCase に対し, 阻害活性をまったく示さなかった. これらの両除草剤のALSに対する阻害活性は高かったが, NAの処理によってALS活性阻害は減少した. また, これらの両除草剤を処理するとトウモロコシの組織に pyruvate が蓄積されたが, NAを処理したトウモロコシの組織では蓄積されなかった. したがって, NA処理による薬害軽減作用には, ALSと ACCase などの酵素活性増加および pyruvate 蓄積の抑制などが部分的に関与していると考えられる.
Ensamble de clasificadores para determinar el perfil académico del estudiante usando árboles de decisión y redes neuronales

Resumen. En este artículo, se propone el uso de un ensamble de clasificadores para determinar el perfil académico del estudiante, basado en su promedio general y en datos relacionados a los factores educativos: actividades de estudio, formas de aprendizaje y hábitos de estudio. Los datos usados se obtuvieron del cuestionario socioeconómico aplicado a los estudiantes del Centro Universitario UAEM Valle de México, asignándole la clase correspondiente de acuerdo con su promedio general. Las clases se definieron como excelente, bueno y regular. Para cada grupo de factores
Imbalance in antioxidant defence and human diseases: Multiple approach of natural antioxidants therapy

The origin of diseases of multifactorial natur e is being understood now due to vitiation in the basic homeostatic balance phenomenon in the body. A majority of disease conditions like atherosclerosis, hypertension, ischaemic diseases, Alzheimer’s disease, Parkinsonism, cancer and inflammatory conditions are being considered caused primarily due to the imbalance between pro-oxidant and antioxidant homeostasis. Antioxidant principles from natural resources possess multifacetedness in their multitude and magnitude of activities and provide enormous scope in correcting the imbalance. Therefore, much attention is being directed to harness and harvest the antioxidant principles from natural resources. In the light of present under standing about the role of free radicals in pathogenesis of multiple diseases, this article provides an account of multifaceted activities of antioxidants and discusses the multiple approach due to which these phytochemicals deserve proper position in therapeutic armamentarium.
Original Research Report A Real-Time PCR Approach to Evaluate Adipogenic Potential of Amniotic Fluid-Derived Human Mesenchymal Stem Cells

Regulation of adipocyte differentiation is an important process in the control of adipose tissue development. So far, adipogenesis has been investigated through the use of various experimental models. In this work, we used human mesenchymal stem cells (hMSCs) obtained from amniotic fluid (AF) as an alternative model more representative of what naturally happens in vivo. In our opinion, these hMSCs are still not influenced by differentiation stimuli and could act in a way more correspondent to the physiological process of adipogenesis, representing also an ethically acceptable alternative to totipotent human embryonic stem cells (ES). Adipocyte differentiation was monitorated following the expressions of key genes. We measured the expression levels of PPAR� 2, PPAR� -C1� , UCP-1, adipsin, and leptin genes using quantitative real-time PCR. We tested our experimental model with two different media. Understanding in vivo adipogenesis mechanisms will shed light on the pathophysiology of many diseases.
Nonlinear propagation in optical fibers : from soliton radiations to multimode instabilities

Ces travaux de these portent sur l'etude de la propagation non lineaire de la lumiere dans les fibres optiques. Nous nous sommes concentres sur deux types de problemes: les solitons dans les fibres monomode et la propagation de la lumiere multimodes dans les fibres a gradient d'indice. Lorsque la frequence porteuse d’un soliton est proche de la longueur d'onde de dispersion nulle ou que la birefringence de la fibre est prise en compte, les solitons peuvent interagir avec des ondes de faible amplitude et generer de nouvelles frequences. Nous avons etudie theoriquement l'efficacite de ces processus dans le cas de solitons sombres qui se propagent pres de longueur d'onde de dispersion nulle et de solitons brillants dans une fibre hautement birefringente. Les resultats de ces analyses ont ete valides par des experiences.Dans les fibres monomodes, les effets physiques etudies sont limites au domaine temporel. Dans la deuxieme partie de cette these, nous augmentons les degres de liberte en utilisant des fibres multimode a gradient d’indice. Un effet qui se produit dans les fibres GRIN est auto-imagerie, un processus dans lequel le faisceau injecte a l'entree se replique periodiquement le long de la fibre, creant un reseau d'indice du a l’effet Kerr de la silice. En raison de ce comportement periodique, certaines frequences sont amplifiees (processus appele instabilite parametrique geometrique). Nous avons caracterise la distribution des frequences instables quand une variation periodique du diametre de la fibre est realisee. Nous presentons egalement un modele unidimensionnel capable d'imiter la dynamique spatio-temporelle de la lumiere dans une fibre multimode.
Molecular Biology of Epstein-Barr Virus

This chapter discusses the pathologies associated with Epstein-Barr virus (EBV) infection. Infection with EBV usually occurs early in childhood and results in an asymptomatic infection. The majority of EBV isolates in Western communities are type 1, while type 2 EBV isolates appear to be largely restricted to equatorial Africa and Papua New Guinea. EBV, in contrast to herpes simplex virus (HSV), has a limited host range. This restriction is at least partially due to absence of the cellular receptor CD21 for EBV, which is also the receptor for the C3d component of complement. In addition to the essential components, EBV DNA encodes two genes that augment viral DNA replication. It is likely that the role of BHRF1 in EBV is to protect latently infected cells in vivo when they switch from latent infection to lytic infection when there is an absence of or very low Bcl2 expression, thus delaying apoptosis induced by lytic replication and ensuring productive lytic replication. EBV-transformed and latently infected lymphoblastoid cell lines (LCLs) express nine proteins and two small RNAs when grown in tissue culture. The proteins are expressed either in the nucleus (Epstein-Barr nuclear antigen [EBNA]) or in the plasma membrane (latent membrane protein [LMP]), and recent work has elucidated many of their functions. EBNA1 binds the 20-bp sequence as a homodimer. The structure of EBNA1 bound to DNA has been solved. Key elements in that structure determination are discussed in the chapter.
Why do Firms Change Their Dividend Policy

Prior literature has largely documented managers’ preference of sticking to their dividend policy. This perceived inflexibility of managers makes a dividend policy switch an important milestone in a firm’s life. Blau and Fuller (2008) state that existing theories do not help understand why some firms never pay dividends, while others consistently pay them. This paper examines the factors that motivate managers to change their long term dividend policy. By employing univariate and multivariate tests and propensity score matching method, the authors provide empirical evidence consistent with the life cycle theory of dividends and Litner’s proposition, and inconsistent with the signaling theory of dividends. Unlike previous studies, by investigating the characteristics of dividend policy switchers, this study examines factors affecting firms’ long term dividend policy. In addition, by analyzing both positive and negative switchers, this study helps to determine whether the same factors are responsible for dividend abandonments and initiations.