Numerical Modelling of Caseless Ammunition with Coreless Bullet in Internal Ballistics

In the search of a new weapon for combat in short range, it is proposed the use of a new experimentally designed 7.62 mm calibre ammunition with a lighter weight (caseless-coreless). This can be used in carbine assault rifles with short barrel or pistols. In this work, the compressible gases flowing through the gun barrel caused by the proposed ammunition were experimentally and numerically analysed. The Large Eddy Simulation was used for the numerical simulation, considering a compressible and turbulent flow, with the chemical species transport model and a complete conversion of the propellant reaction. Variations in pressure and temperature were compared with the results obtained from a conventional 7.62 mm full metal jacket (FMJ) ammunition. Results of ballistic experimental tests and numerical simulations were similar than those of the 9 mm x 19 mm FMJ ammunitions, showing feasibility for the development of new weapons intended for operations of short range shots.Defence Science Journal, Vol. 65, No. 3, May 2015, pp.203-207, DOI: http://dx.doi.org/10.14429/dsj.65.851

La evaluación de la calidad de enseñanza universitaria mediante la percepción del alumno de una actividad práctica: propuesta de escalas de medida

El panorama universitario actual, centrado en la valoración y juicio de los distintos agentes del proceso de enseñanza-aprendizaje, supone un campo adecuado para el desarrollo de investigaciones que pretendan alcanzar indicadores fiables del desempeño de las labores docentes. La futura implantación del Espacio Europeo de Educación Superior (EEES), acrecienta el interés por este tipo de investigaciones.Este trabajo, centrado en este contexto, pretende evaluar y valorar, por parte del discente, una actividad práctica constitutiva del programa de dos asignaturas universitarias impartidas en dos licenciaturas oficiales. Para su evaluación desarrollaremos una escala de medida que permita conocer la percepción de calidad de dicha actividad por parte de los alumnos y las posibles fuentes de mejora. Con los resultados obtenidos podremos conocer que aportación tiene esta práctica en el proceso de aprendizaje de esta materia y para la formación general del alumno

Efecto del ácido salicílico sobre la formación de callos en tres clones de Theobroma cacao L.

Cocoa is a crop of great economic importance and it has interest as a source of naturally occurring compounds. The tissue culture using metabolic elicitation is an alternative for large scale production of secondary metabolites. This study aimed to determine the effect of salicylic acid as elicitor for the production of cell biomass of Theobroma cacao L. in three clones. For callus formation staminodes of ‘UF-613’, ‘UF-650’ and ‘Pound-7’ clones were used. It were added 0.02, 0.05, 0.10 and 0.15 mg l-1 salicylic acid to the culture medium. At 15 and 28 days of culture the number of explants formed callus were quantified and the percentage of callus formation was calculated. In the best results clone the secondary metabolites in callus and culture medium were identified by phytochemical screening. The addition of salicylic acid accelerated callus formation in the cocoa clones ‘UF-613’, ‘UF-650’ and ‘Pound-7’. The results depended of the clone and the concentrations used. The identification of secondary metabolites in callus of ‘UF-650’ clone and in the culture medium is the starting point for future research. Key words: tissue culture, phytochemical screening, secondary metabolites.El cacao es un cultivo de gran importancia económica que resulta de interés como fuente de compuestos de origen natural. El cultivo de tejidos con empleo de elicitación metabólica es una alternativa para la producción a gran escala de estos metabolitos secundarios. El presente trabajo tuvo como objetivo determinar el efecto del ácido salicílico como elicitor para la producción de biomasa celular de Theobroma cacao L. en tres clones. Para la formación de callos se utilizaron estaminoides de los clones ‘UF-613’, ‘UF-650’ y ‘Pound-7’. Se adicionaron 0.02; 0.05; 0.10 y 0.15 mg l-1 de ácido salicílico al medio de cultivo. A los 15 y 28 días de cultivo se cuantificó el número de explantes que formaron callos y se calculó el porcentaje de formación de callos. En el clon de mejores resultados se identificaron los metabolitos secundarios presentes en callos y medio de cultivo mediante tamizaje fitoquímico. La adición de ácido salicílico aceleró la formación de callos en los clones de cacao ‘UF-613’, ‘UF-650’ y ‘Pound-7’. Los resultados dependieron del clon y de las concentraciones utilizadas. La identificación de metabolitos secundarios en callos del clon ‘UF-650’ y en el medio de cultivo es punto de partida para futuras investigaciones. Palabras clave: cultivo in vitro, metabolitos secundarios, tamizaje fitoquímico

Twist and shout: a surprising synergy between aryl and N-substituents defines the computed charge transport properties in a series of crystalline diketopyrrolopyrroles

This is the Accepted Manuscript version of an article accepted for publication in CyrstEngComm. Under embargo. Embargo end date: 22 November 2017. Jesus Calvo-Castrp, Sebastian Macza, Connor Thomson, Graeme Morris, Alan R. Kennedy and Callum J. McHugh, ‘Twist and shout: a surprising synergy between aryl and N-substituents defines the computed charge transport properties in a series of crystalline diketopyrrolopyrroles’, CrysEngComm, Vol 18(48): 9382-9390, first published online 22 November 2016, available at doi: 10.1039/C6CE02261HThe influence of systematic variation of aryl and N-substitution on predicted charge transport behaviour in a series of crystalline diketopyrrolopyrroles is evaluated. A correct combination of substituents is revealed to maximise those properties which dictate device performance in organic single crystals based upon this structural motif. For electron transport, furan and N-alkyl substitution emerge as optimal molecular design strategies, whilst phenyl structures bearing N-benzyl substituents are shown to offer the most significant promise as highly sought after crystalline hole transport materials.Peer reviewedFinal Accepted Versio

Expanding the knowledge about Leishmania species in wild mammals and dogs in the Brazilian savannah

Background: Wild, synanthropic and domestic mammals act as hosts and/or reservoirs of several Leishmania spp. Studies on possible reservoirs of Leishmania in different areas are fundamental to understand host-parasite interactions and develop strategies for the surveillance and control of leishmaniasis. In the present study, we evaluated the Leishmania spp. occurrence in mammals in two conservation units and their surroundings in Brasília, Federal District (FD), Brazil. Methods: Small mammals were captured in Brasília National Park (BNP) and Contagem Biological Reserve (CBR) and dogs were sampled in residential areas in their vicinity. Skin and blood samples were evaluated by PCR using different molecular markers (D7 24Sα rRNA and rDNA ITS1). Leishmania species were identified by sequencing of PCR products. Dog blood samples were subjected to the rapid immunochromatographic test (DPP) for detection of anti-Leishmania infantum antibodies. Results: 179 wild mammals were studied and 20.1% had Leishmania DNA successfully detected in at least one sample. Six mammal species were considered infected: Clyomys laticeps, Necromys lasiurus, Nectomys rattus, Rhipidomys macrurus, Didelphis albiventris and Gracilinanus agilis. No significant difference, comparing the proportion of individuals with Leishmania spp., was observed between the sampled areas and wild mammal species. Most of the positive samples were collected from the rodent N. lasiurus, infected by L. amazonensis or L. braziliensis. Moreover, infections by Trypanosoma spp. were detected in N. lasiurus and G. agilis. All 19 dog samples were positive by DPP; however, only three (15.8%) were confirmed by PCR assays. DNA sequences of ITS1 dog amplicons showed 100% identity with L. infantum sequence. Conclusions: The results suggest the participation of six species of wild mammals in the enzootic transmission of Leishmania spp. in FD. This is the first report of L. amazonensis in N. lasiurus

Impacto de un programa intervención em alunos del segundo ciclo

O objetivo do presente estudo consistiuem avaliar um programa de intervenção junto a alunos do 2º ciclo de escolaridade nas seguintes dimensões: tomada de decisão, conhecimentos sobre sexualidade, competências sociais, assertividade e autoconceito. Metodologia: Participaram 145 alunos, distribuídos pelos grupos controle e experimental. Os instrumentos utilizados foram: TCU Decision-Making; Questionário de Conhecimentos sobre Sexualidade; Assertion Self-Statement Test- Revised; Questionário de Competências Sociais; Piers-Harris Children’s Self-Concept Scale. Os resultados revelaram diferenças no pós-teste entre os grupos ao nível da sexualidade. Verificaram-se diferenças do pré-teste para o pós-teste no grupo experimental nos níveis da sexualidade, da assertividade e das competências sociais. No grupo experimental encontraram-se associações positivas entre tomada de decisão, competências sociais e assertividade, bem como entre sexualidade, competências sociais e autoconceito, no pós-teste. Os preditores da assertividade no pós-teste foram tomada de decisão, sexualidade e competências sociais. Como conclusão, os resultados enfatizam a importância de intervenção junto a adolescentes, particularmente na tomada de decisão, na sexualidade e nas competências sociais. Palavras-chave: Habilidades sociais, sexualidade, autoconceito.In this study we evaluate an intervention program in the following dimensions: Decision Making, Knowledge on Sexuality, Social Skills, Assertiveness and Self-Concept with students in 5th and 6th grade. Methodology: 145 students participated in the study divided by control and experimental group. The instruments used were: Decision-Making TCU, Knowledge on Sexuality Questionnaire; Assertion Self-Statement Test-Revised;Social Skills Questionnaire, and Piers-Harris Children's Self- Concept Scale. The results indicate differences at post-test between the groups on knowledge regarding sexuality. There were also differences from pre-test to post-test in the experimental group on knowledge on sexuality, assertiveness and social skills. Positive associations among decision making, social skills and assertiveness were found as well as among knowledge on sexuality, social skills and self-concept, in the experimental group, in the pos-test. Finally, the predictors of assertiveness regarding health behaviors, in the pos-test were: decision making, knowledge regarding sexuality and social skills. The results emphasize the importance of intervention for adolescents in terms of health promotion particularly in decision making, sexuality and social skills.El objetivo del presente estudio fue evaluar un programa de intervención con alumnos del 2º ciclo de escolaridad en las siguientes dimensiones: Toma de Decisión, Conocimientos sobre Sexualidad, Habilidades Sociales, Asertividad y Autoconcepto. Metodología: Participaron 145 alumnos, distribuidos en grupo control y experimental. Los instrumentos utilizados fueron: TCU Decision-Making; Cuestionario de Conocimientos sobre Sexualidad; AssertionSelf-Statement Test-Revised; Cuestionario de Habilidades Sociais; Piers-Harris Children'sSelf-Concept Scale. Los resultados mostraron diferencias en el post-test entre los grupos en cuanto a la sexualidad. Se verificaron diferencias del pre-test para el post-teste en el grupo experimental, cuanto a sexualidad, asertividad y habilidades sociales. Se encontraron asociaciones positivas entre toma de decisión, habilidades sociales y asertividad, así como entre sexualidad,habilidades sociales yautoconcepto, en el post-test en el grupo experimental. Los predictores de la asertividad en el post-test fueron toma de decisión, sexualidad y habilidades sociales. Los resultados destacan la importancia de la intervención con adolescentes particularmente en la toma de decisiones, sexualidad y habilidades sociales.(undefined

Alternative Oxidase Mediates Pathogen Resistance in Paracoccidioides brasiliensis Infection

Thermally dimorphic pathogenic fungi are responsible for potentially life-threatening diseases of immunocompetent and immunocompromised individuals. These microorganisms grow as conidia-producing mycelia in the environment, which when inhaled by the host convert to the pathogenic yeast form at 37°C. During adaptation and growth, fungi interact with host immune cells and must cope with defense mechanisms such as imposed-oxidative stress (e.g., reactive oxygen species; ROS). Alternative oxidase (AOX) is an enzyme recently implicated in the reduction of ROS production by the mitochondria when triggered by external stimuli, such as temperature and ROS. During this work we have evaluated the relevance of AOX during infection with Paracoccidioides brasiliensis, the etiological agent of one of the most prevalent mycoses in Latin America, paracoccidioidomycosis. We show that PbAOX gene expression is stimulated after interaction with alveolar macrophages or in the presence of H2O2 and is essential for survival against fungicidal activity of both the immune cells and the ROS compound. Moreover, decreasing PbAOX gene expression in P. brasiliensis led to increased survival of infected mice. Altogether, our data supports a relevant role for AOX in the virulence of P. brasiliensis

Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice

Chronic pulmonary disease and skin/soft tissue infections due to non-tuberculous mycobacteria (NTM) of the Mycobacterium chelonae-abscessus-massiliense group is an emerging health problem worldwide. Moreover, the cure rate for the infections this group causes is low despite aggressive treatment. Post-surgical outbreaks that reached epidemic proportions in Brazil recently were caused by M. massiliense isolates resistant to high-level disinfection with glutaraldehyde (GTA). Understanding the differences in the virulence and host immune responses induced by NTM differing in their sensitivity to disinfectants, and therefore their relative threat of causing outbreaks in hospitals, is an important issue.We compared the replication and survival inside macrophages of a GTA-susceptible reference Mycobacterium massiliense clinical isolate CIP 108297 and an epidemic strain from Brazil, CRM-0019, and characterized the immune responses of IFNγ knockout mice exposed to a high dose aerosol with these two isolates. CRM-0019 replicated more efficiently than CIP 108297 inside mouse bone marrow macrophages. Moreover, the animals infected with CRM-0019 showed a progressive lung infection characterized by a delayed influx of CD4+ and CD8+ T cells, culminating in extensive lung consolidation and demonstrated increased numbers of pulmonary CD4+ Foxp3+ regulatory T cells compared to those infected with the reference strain. Immunosuppressive activity of regulatory T cells may contribute to the progression and worsening of NTM disease by preventing the induction of specific protective immune responses.These results provide the first direct evidence of the increased virulence in macrophages and mice and pathogenicity in vivo of the Brazilian epidemic isolate and the first observation that NTM infections can be associated with variable levels of regulatory T cells which may impact on their virulence and ability to persist in the host