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Fomites might be responsible for virus introduction in swine farms, highlighting the importance of implementing practices to minimize the probability of virus introduction. The study's objective was to assess the efficacy of different combinations of temperatures and holding-times on detecting live PRRSV and PEDV on surfaces commonly found in supply entry rooms in swine farms. Two PRRSV isolates (MN 184 and 1-4-4 L1C variant) and one PEDV isolate (NC 49469/2013) were inoculated on cardboard and aluminum. An experimental study tested combinations of four temperatures (20°C, 30°C, 40°C, and 50°C) and six holding-times (15 minutes, 60 minutes, 6 hours, 12 hours, 24 hours, and 36 hours) for the presence of the viruses on each surface type. After virus titration, virus presence was assessed by assessing the cytopathic effects and immunofluorescence staining. The titers were expressed as log10 TCID50/ml, and regression models; half-lives equations were calculated to assess differences between treatments and time to not detect the live virus. The results suggest that the minimum time that surfaces should be held to not detect the virus at 30°C was 24 hours, 40°C required 12 hours, and 50°C required 6 hours; aluminum surfaces took longer to reach the desired temperature compared to cardboard. The results suggest that PRRSV 1-4-4 L1C variant had higher half-lives at higher temperatures than PRRSV MN 184. In conclusion, time and temperature combinations effectively decrease the concentration of PRRSV and PEDV on different surfaces found in supply entry rooms in swine farms.
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Síndrome Respiratorio y de la Reproducción Porcina , Virus de la Diarrea Epidémica Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Porcinos , Animales , Temperatura , AluminioRESUMEN
To achieve the new level of blended cement performance, the slurries of Class C and F fly ash were mechano-chemically activated in a vibro-mill with superplasticizer and nanosilica. The resulting activated products were tested in mortars replacing up to 30% portland cement. The activation process resulted in the formation of nano-seed clusters and micronized ash particles that both significantly improve the early strength of mortars as well as allow for the replacement of portland cement with industrial by-products. A small amount, 0.1% (of a binder weight), of nanosilica was used in selected compositions to improve the process of activation and facilitate the formation of nano-seeds. Due to an intensive activation of fly ash in the vibro-mill and the formation of nano-seed hydration products, the increase in the heat of the hydration flux and improvement of the mechanical properties such as compressive strength, especially in the early stages of hardening, were achieved. It is envisioned that fly ash activation and the use of supplementary cementitious materials as a precursor can induce a denser structure of cementitious matrix due to better particle packing realized with the application of the nano-seed product, nanosilica, ultra-fine particles of fly ash, and the formation of a refined C-S-H structure realized with the incorporation of the nano-seed particles.
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Ultrahigh performance concrete (UHPC), which is characterized by dense microstructure and strain hardening behavior, provides exceptional durability and a new level of structural response to modern structures. However, the design of the UHPC matrix often requires the use of high quantities of supplementary cementitious materials, such as silica fume, which can significantly increase the cost and elevate the production expenses associated with silica fume handling. This paper demonstrates that a fiber-reinforced composite with properties similar to conventional UHPC can be realized with very low quantities of silica fume, such as 1% by mass of cementitious materials. The proposed UHPC is based on reference Type I cement or Type V Portland cement with very low C3A (<1%) that also complies with Class H oil well cement specification, silica fume, small quantities of Al2O3 nanofibers, and high-density polyethylene or polyvinyl alcohol macro fibers. Previous research has demonstrated that nanofibers act as a seeding agent to promote the formation of compact and nanoreinforced calcium silicate hydrate (C-S-H) clusters within the interparticle and nanofiber spaces, providing a nanoreinforcing effect. This approach produces a denser and stronger matrix. This research expands upon this principle by adding synthetic fibers to ultrahigh strength cement-based composites to form a material with properties approaching that of UHPC. It is indicated that the developed material provides improved strain hardening and compressive strength at the level of 160 MPa.
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We report here, for the first time in the literature, a method to synthesize hydrophobic and superhydrophobic concrete. Concrete is normally a hydrophilic material, which significantly reduces the durability of concrete structures and pavements. To synthesize water-repellent concrete, hydrophobic emulsions were fabricated and applied on portland cement mortar tiles. The emulsion was enriched with the polymethyl-hydrogen siloxane oil hydrophobic agent as well as metakaolin (MK) or silica fume (SF) to induce the microroughness and polyvinyl alcohol (PVA) fibers to create hierarchical surfaces. Various emulsion types were investigated by using different mixing procedures, and single- and double-layer hydrophobic coatings were applied. The emulsions and coatings were characterized with optical microscope and scanning electron microscope (SEM), and their wetting properties, including the water contact angle (CA) and roll-off angle, were measured. A theoretical model for coated and non-coated concrete, which can be generalized for other types of materials, was developed to predict the effect of surface roughness and composition on the CA. An optimized distance between the aggregates was found where the CA has the highest value. The maximal CA measured was 156° for the specimen with PVA fibers treated with MK based emulsion. Since water penetration is the main factor leading to concrete deterioration, hydrophobic water-repellent concretes have much longer durability then regular concretes and can have a broad range of applications in civil and materials engineering.
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This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190 mV and ISC of ~9 µA, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46 mW confirmed the generation of electrical power of ~0.64 µW with almost half generated via battery effect. This work presents a first step towards realizing the additional pathways to low-cost electrical power production in urban environments based on a combined use of organic dyes, nanotitania and concrete technology.
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Arrythmogenic right ventricular dysplasia (ARVD) is rare disease but it is a major cause of sudden death in young people and in athletes. ARVD is a cardiomyopathy characterized by structural and functional abnormalities of the right ventricle precipitating its electrical instability. This electrical instability is responsible for ventricular arrhythmias. Sudden death, by ventricular fibrillation, may be the first symptom of the disease. The diagnosis is based upon specific ventricular pathology at the histological level as well as typical electrocardiographic and diagnostic imaging features. A better understanding of the disease has increased along with the new data on genetics. Its management remains a challenge because of the wide spectrum of clinical presentation as well as its natural history. We present a case of ARVD and its evolution in order to show the difficulties of the management of this particular entity.
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Arritmias Cardíacas/diagnóstico por imagen , Displasia Ventricular Derecha Arritmogénica/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Adulto , Diástole , Ecocardiografía , Imagen de Acumulación Sanguínea de Compuerta/métodos , Humanos , Masculino , RadiografíaRESUMEN
La educación sexual constituye una necesidad en la sociedad, porque tiene como objetivos básicos capacitar a la persona para que en sus relaciones con el otro sexo pueda disfrutar plenamente de los valores humanos y crear condiciones materiales y espirituales óptimas para el fortalecimiento de los más legítimos sentimientos de amor, respeto y solidaridad que sobre la base de la plena igualdad deben existir entre sus miembros;teniendo esto en cuenta, así como la alta incidencia que tienen en la actualidad las Infecciones de Transmisión Sexual, fue objetivo de esta investigación indagar sobre los conocimientos que tienen los jóvenes sobre el tema; así fue como decidimos abordarlo en 204 jóvenes con edades entre 12 y 15 años, en una escuela de nivel secundario, en el período de enero a junio del 2005. Se realizó estudio observacional, descriptivo, transversal sobre el conocimiento de los adolescentes acerca de sexualidad y enfermedades de transmisión sexual. Se aplicó encuesta que mostró desconocimiento por parte de los jóvenes acerca de las Infecciones de Transmisión Sexual, a pesar de que todos los jóvenes declararon haber recibido información sobre el tema. Existió poca congruencia entre los alumnos que habían practicado el sexo y los conocimientos de éstos sobre el tema abordado. Pudo apreciarse poca utilización de protección (condón) por parte de los estudiantes. Se evidenció que tanto el nivel escolar de los padres como el estado civil de los mismos influyeron notablemente en los conocimientos de sus hijos sobre Infecciones de Transmisión Sexual. Se señaló a la escuela y la TV como las fuentes que más le brindan información sobre el tema. Entre los lugares a los que acuden a pedir ayuda se encuentra la casa de amigos y del novio
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Humanos , Adolescente , Enfermedades de Transmisión Sexual/epidemiología , Educación Sexual/métodosRESUMEN
La educación sexual constituye una necesidad en la sociedad, porque tiene como objetivos básicos capacitar a la persona para que en sus relaciones con el otro sexo pueda disfrutar plenamente de los valores humanos y crear condiciones materiales y espirituales óptimas para el fortalecimiento de los más legítimos sentimientos de amor, respeto y solidaridad que sobre la base de la plena igualdad deben existir entre sus miembros;teniendo esto en cuenta, así como la alta incidencia que tienen en la actualidad las Infecciones de Transmisión Sexual, fue objetivo de esta investigación indagar sobre los conocimientos que tienen los jóvenes sobre el tema; así fue como decidimos abordarlo en 204 jóvenes con edades entre 12 y 15 años, en una escuela de nivel secundario, en el período de enero a junio del 2005. Se realizó estudio observacional, descriptivo, transversal sobre el conocimiento de los adolescentes acerca de sexualidad y enfermedades de transmisión sexual. Se aplicó encuesta que mostró desconocimiento por parte de los jóvenes acerca de las Infecciones de Transmisión Sexual, a pesar de que todos los jóvenes declararon haber recibido información sobre el tema. Existió poca congruencia entre los alumnos que habían practicado el sexo y los conocimientos de éstos sobre el tema abordado. Pudo apreciarse poca utilización de protección (condón) por parte de los estudiantes. Se evidenció que tanto el nivel escolar de los padres como el estado civil de los mismos influyeron notablemente en los conocimientos de sus hijos sobre Infecciones de Transmisión Sexual. Se señaló a la escuela y la TV como las fuentes que más le brindan información sobre el tema. Entre los lugares a los que acuden a pedir ayuda se encuentra la casa de amigos y del novio.
Sexual education is a society's necessity, because its main objectives are qualifying persons in that way that they could fully enjoy the human values in their relation with the other sex and creating optimal spiritual and material conditions to strengthen the most legitimated feelings of love, respect and solidarity on the basis of the full equality that should exist between the parts of a couple; taking this in to account, and also the high incidence of the sexual transmitted infections, the objective of this investigation was to look into the knowledge youngster have about the theme; we also decided to debate the theme with 204 12-to-15 years-old adolescents, in a secondary high school, from January to June 2005. We made a transversal, descriptive, observational study on the adolescents´ knowledge about sexuality and sexual transmitted diseases. We applied a query, showing lack of knowledge on the sexual transmitted diseases by youth, even though all of them declared that they received information on the theme. There was little congruence between the answers of the students that had already practice love and their knowledge on the studied theme. We could appreciate the little use of protection (condom) by students. There was evidence that parent's scholarship as much as their marital status notably influence on their children knowledge about sexual transmitted diseases. They showed school and television as the sources giving them more information on the theme. Their friends and boy (girl) friends' houses are among the most common places where they usually ask for help.
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Humanos , Adolescente , Conocimientos, Actitudes y Práctica en Salud , Educación Sexual/métodos , Enfermedades de Transmisión Sexual/epidemiologíaRESUMEN
Intracellular efflux pumps have been largely the research focus in multidrug-resistant (MDR) Gram-positive and Gram-negative microorganisms and parasites including cancers. However, drug efflux mechanisms other than pumps per se have been observed, supported by the effects of isomeric, non-antibiotic depressant (DPR), phenothiazines and thixenes, and antidepressant (ADPR) phenylpiperidine neurotropic drugs, alone or in combination with classical antimicrobials on MDR Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus pyogenes and Streptococcus pneumoniae. Of the non-antibiotics we investigated, the DPR l-thioridazine, trans-clopenthixol and isomers of phenylpiperidines NNC 20-4962 (isomer of femoxetine) and NNC 20-7052 (isomer of paroxetine) were potent antimicrobials with the least neurotropic activity, pointing to a possible general isomeric structure-activity relationship. These compounds may be regarded as new efflux inhibitors. Moreover, these isomers have considerably reduced, in some cases absent, neurotropism and reduced mammalian toxicity. This may alleviate concerns about adverse effects and therapeutic safety for infected patients in life-threatening situations where the non-antibiotic dosage would be in the lower, non-chronic dosage ranges generally prescribed for individuals with mild mental health problems. The results point to the prokaryotic and eukaryotic microorganisms' phospholipid/protein domain involvement of the cationic, amphiphilic, non-antibiotic DPR and ADPR, with the phospholipids being the initial sites attracting and concentrating the neurotropes to induce a form of suspended animation, followed by gross changes of cell wall and membrane structure, and thereby potentiating their destructive or immobilizing effects on various as yet only hinted at resistance and efflux mechanisms. Combination of appropriate isomeric non-antibiotic DPR and ADPR of low neurotropism and toxicity with conventional and classical antimicrobials promises early, new therapeutic strategies salutary against microbial resistance, resistance development, pathogenicity and virulence.
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Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Fenotiazinas/farmacología , Animales , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Bacterias Grampositivas/efectos de los fármacos , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Mycobacterium/efectos de los fármacos , Fenotiazinas/efectos adversos , Fenotiazinas/uso terapéutico , Fosfolípidos/metabolismoRESUMEN
A series of neuroleptic protonated phenothiazine derivatives (promethazine, promazine, triflupromazine, methotrimeprazine, propiomazine, trifluoperazine and fluphenazine), some with known anticancer properties, were complexed with water-insoluble antineoplastice agents such as 5-fluorouracil (5FU), methotrexate (MTX) and sulindac, as well as with components of biomembrane and synthetic phospholipids as possible models of cancer and microbial cells. In all cases water-soluble micellar inclusion adducts were formed exhibiting electron charge transfer complex behaviour, with the appearance of thazine free radicals. The thiazines sequestered the drugs and phospholipids in well-defined molar ratios (MR) parabolically-dependent on the dipole moments (mu) of the protonated phenothiazine derivatives. pH comparisons showed that the inclusion adducts followed a model in which the compounds were enveloped in the lipophilic interior of the thiazine aggregates, while the side-chains of the latter faced the aqueous environment. In the model experiment, interaction of the thiazines and the 5FU adducts with E. coli F' lac was additive to marginally synergistic, confirmed by the checkerboard technique. The parabolic dependence of the molar minimum inhibitory concentration of the thiazines and thiazine/5FU adducts on the thiazine dipole moments suggests that their primary loci of interaction are the cell wall or membrane phospholipid components. Thiazines, especially those with dipole moments centered on about 6 D, near which the lowest MR occurs, can act as effective carriers for insoluble or sparsely soluble drugs. Any new thiazine drug for use alone or as a carrier in anticancer therapy should be designed with this criterion in mind.