Towards an Analysis of Study Habits of University Students

This paper looks at the study workload for a sample of undergraduate students during 30 min intervals over 7x24 hours. Students at the Danmarks Tekniske Universitet in Denmark and the Universidad de los Andes in Bogotá, Colombia, took part in the experiment, which focused on physics and mathematics students. Detailed data was obtained for the total study workload, the study workload during the day and during the week, the different study activities, and the differences in workload between different students. Significant differences are found between the study practices of the students at the two institutions. Further work is required to make adjustments to the teaching and learning programmes

In Silico Survey and Characterization of Babesia microti Functional and Non-Functional Proteases

Human babesiosis caused by the intraerythrocytic apicomplexan Babesia microti is an expanding tick-borne zoonotic disease that may cause severe symptoms and death in elderly or immunocompromised individuals. In light of an increasing resistance of B. microti to drugs, there is a lack of therapeutic alternatives. Species-specific proteases are essential for parasite survival and possible chemotherapeutic targets. However, the repertoire of proteases in B. microti remains poorly investigated. Herein, we employed several combined bioinformatics tools and strategies to organize and identify genes encoding for the full repertoire of proteases in the B. microti genome. We identified 64 active proteases and 25 nonactive protease homologs. These proteases can be classified into cysteine (n = 28), serine (n = 21), threonine (n = 14), asparagine (n = 7), and metallopeptidases (n = 19), which, in turn, are assigned to a total of 38 peptidase families. Comparative studies between the repertoire of B. bovis and B. microti proteases revealed differences among sensu stricto and sensu lato Babesia parasites that reflect their distinct evolutionary history. Overall, this data may help direct future research towards our understanding of the biology and pathogenicity of Babesia parasites and to explore proteases as targets for developing novel therapeutic interventions.Instituto de PatobiologíaFil: Florin-Christensen, Monica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Florin-Christensen, Monica. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wieser, Sarah Nathaly. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina.Fil: Wieser, Sarah Nathaly. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Suarez, Carlos E. USDA-ARS. Animal Disease Research Unit; Estados UnidosFil: Suarez, Carlos E. Washington State University. Department of Veterinary Microbiology and Pathology; Estados UnidosFil: Schnittger, Leonhard. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Schnittger, Leonhard. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Thermal and Dynamical Particle Creation in a Curved Geometry

A generalization of ``Termo Field Dynamics'' to a curved geometry is proposed. In particular a neutral scalar field minimally coupled to gravity is considered as matter content in a Robertson-Walker metric. A non linear amplification in the particle creation is obtained, due to the altogether action of thermal and geometric effects. As a consequence the frequencies in the system look like red shifted with respect to the case where the thermal creation is not taken into account.Comment: 13 page

Bovipain-2, the falcipain-2 ortholog, is expressed in intraerythrocytic stages of the tick-transmitted hemoparasite Babesia bovis

<p>Abstract</p> <p>Background</p> <p>Cysteine proteases have been shown to be highly relevant for Apicomplexan parasites. In the case of <it>Babesia bovis</it>, a tick-transmitted hemoparasite of cattle, inhibitors of these enzymes were shown to hamper intraerythrocytic replication of the parasite, underscoring their importance for survival.</p> <p>Results</p> <p>Four papain-like cysteine proteases were found to be encoded by the <it>B. bovis </it>genome using the MEROPS database. One of them, the ortholog of <it>Plasmodium falciparum </it>falcipain-2, here named bovipain-2, was further characterized. Bovipain-2 is encoded in <it>B. bovis </it>chromosome 4 by an ORF of 1.3 kb, has a predicted molecular weight of 42 kDa, and is hydrophilic with the exception of a transmembrane region. It has orthologs in several other apicomplexans, and its predicted amino acid sequence shows a high degree of conservation among several <it>B. bovis </it>isolates from North and South America. Synteny studies demonstrated that the <it>bovipain-2 </it>gene has expanded in the genomes of two related piroplasmids, <it>Theileria parva </it>and <it>T. annulata</it>, into families of 6 and 7 clustered genes respectively. The <it>bovipain-2 g</it>ene is transcribed in <it>in vitro </it>cultured intra-erythrocyte forms of a virulent and an attenuated <it>B. bovis </it>strain from Argentina, and has no introns, as shown by RT-PCR followed by sequencing. Antibodies against a recombinant form of bovipain-2 recognized two parasite protein bands of 34 and 26 kDa, which coincide with the predicted sizes of the pro-peptidase and mature peptidase, respectively. Immunofluorescence studies showed an intracellular localization of bovipain-2 in the middle-rear region of <it>in vitro </it>cultured merozoites, as well as diffused in the cytoplasm of infected erythrocytes. Anti-bovipain-2 antibodies also reacted with <it>B. bigemina</it>-infected erythrocytes giving a similar pattern, which suggests cross-reactivity among these species. Antibodies in sera of two out of six <it>B. bovis</it>-experimentally infected bovines tested, reacted specifically with recombinant bovipain-2 in immunoblots, thus demonstrating expression and immunogenicity during bovine-infecting stages.</p> <p>Conclusions</p> <p>Overall, we present the characterization of bovipain-2 and demonstrate its <it>in vitro </it>and <it>in vivo </it>expression in virulent and attenuated strains. Given the involvement of apicomplexan cysteine proteases in essential parasite functions, bovipain-2 constitutes a new vaccine candidate and potential drug target for bovine babesiosis.</p

Immune responses following neonatal vaccination with conserved F4 fragment of VtaA proteins from virulent Glaesserella parasuis adjuvanted with CAF®01 or CDA

Glaesserella parasuis is a Gram-negative bacterium that colonizes the upper airways of swine, capable of causing a systemic infection called Glässer’s disease. This disease is more frequent in young post-weaning piglets. Current treatments against G. parasuis infection are based on the use of antimicrobials or inactivated vaccines, which promote limited cross-protection against different serovars. For this reason, there is an interest in developing novel subunit vaccines with the capacity to confer effective protection against different virulent strains. Herein, we characterize the immunogenicity and the potential benefits of neonatal immunization with two different vaccine formulations based on the F4 polypeptide, a conserved immunogenic protein fragment from the virulence-associated trimeric autotransporters of virulent G. parasuis strains. With this purpose, we immunized two groups of piglets with F4 combined with cationic adjuvant CAF®01 or cyclic dinucleotide CDA. Piglets immunized with a commercial bacterin and non-immunized animals served as control groups. The vaccinated piglets received two doses of vaccine, at 14 days old and 21 days later. The immune response induced against the F4 polypeptide varied depending on the adjuvant used. Piglets vaccinated with the F4+CDA vaccine developed specific anti-F4 IgGs, biased towards the induction of IgG1 responses, whereas no anti-F4 IgGs were de novo induced after immunization with the CAF®01 vaccine. Piglets immunized with both formulations displayed balanced memory T-cell responses, evidenced upon in vitro re-stimulation of peripheral blood mononuclear cells with F4. Interestingly, pigs immunized with F4+CAF®01 controlled more efficiently a natural nasal colonization by a virulent serovar 4 G. parasuis that spontaneously occurred during the experimental procedure. According to the results, the immunogenicity and the protection afforded by F4 depend on the adjuvant used. F4 may represent a candidate to consider for a Glässer‘s disease vaccine and could contribute to a better understanding of the mechanisms involved in protection against virulent G. parasuis colonization.This study was financially supported by the European Project TRANSVAC2–730964–INFRAIA–2016-1 of the European Vaccine Initiative funded in turn by the European Commission under the Horizon 2020 Program. Sergi López-Serrano was funded by this Project. IRTA-CReSA is also supported by the Centres de Recerca de Catalunya (CERCA) Program from the Generalitat de Catalunya.info:eu-repo/semantics/publishedVersio

N-Glycosylation in piroplasmids : Diversity within simplicity

N-glycosylation has remained mostly unexplored in Piroplasmida, an order of tick-transmitted pathogens of veterinary and medical relevance. Analysis of 11 piroplasmid genomes revealed three distinct scenarios regarding N-glycosylation: Babesia sensu stricto (s.s.) species add one or two N-acetylglucosamine (NAcGlc) molecules to proteins; Theileria equi and Cytauxzoon felis add (NAcGlc)2-mannose, while B. microti and Theileria s.s. synthesize dolichol-P-P-NAcGlc and dolichol-P-P-(NAcGlc)2 without subsequent transfer to proteins. All piroplasmids possess the gene complement needed for the synthesis of the N-glycosylation substrates, dolichol-P and sugar nucleotides. The oligosaccharyl transferase of Babesia species, T. equi and C. felis, is predicted to be composed of only two subunits, STT3 and Ost1. Occurrence of short N-glycans in B. bovis merozoites was experimentally demonstrated by fluorescence microscopy using a NAcGlc-specific lectin. In vitro growth of B. bovis was significantly impaired by tunicamycin, an inhibitor of N-glycosylation, indicating a relevant role for N-glycosylation in this pathogen. Finally, genes coding for N-glycosylation enzymes and substrate biosynthesis are transcribed in B. bovis blood and tick stages, suggesting that this pathway is biologically relevant throughout the parasite life cycle. Elucidation of the role/s exerted by N-glycans will increase our understanding of these successful parasites, for which improved control measures are needed.Instituto de PatobiologíaFil: Florin-Christensen, Mónica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Florin-Christensen, Mónica. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguez, Anabel Elisa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Rodriguez, Anabel Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Suarez, Carlos Esteban. Washington State University. College of Veterinary Medicine. Department of Veterinary Microbiology and Pathology; Estados UnidosFil: Suarez, Carlos Esteban. United States Department of Agricultural-Agricultural Research Service. Animal Disease Research Unit; Estados UnidosFil: Ueti, Massaro W. Washington State University. College of Veterinary Medicine. Department of Veterinary Microbiology and Pathology; Estados UnidosFil: Ueti, Massaro W. United States Department of Agricultural-Agricultural Research Service. Animal Disease Research Unit; Estados UnidosFil: Delgado, Fernando Oscar. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Delgado, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Echaide, Ignacio Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Schnittger, Leonhard. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Schnittger, Leonhard. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Detection strategies for scalar gravitational waves with interferometers and resonant spheres

We compute the response and the angular pattern function of an interferometer for a scalar component of gravitational radiation in Brans-Dicke theory. We examine the problem of detecting a stochastic background of scalar GWs and compute the scalar overlap reduction function in the correlation between an interferometer and the monopole mode of a resonant sphere. While the correlation between two interferometers is maximized taking them as close as possible, the interferometer-sphere correlation is maximized at a finite value of f*d, where `f' is the resonance frequency of the sphere and `d' the distance between the detectors. This defines an optimal resonance frequency of the sphere as a function of the distance. For the correlation between the Virgo interferometer located near Pisa and a sphere located in Frascati, near Rome, we find an optimal resonance frequency f=590 Hz. We also briefly discuss the difficulties in applying this analysis to the dilaton and moduli fields predicted by string theory.Comment: 26 pages, Latex, 4 Postscript figures. Various minor improvements, misprint in eqs. 42, 127, 138 corrected, references adde