Influencia del espesor de la junta de mortero en muros de ladrillo sometidos a esfuerzos de compresión

En este trabajo se analiza la influencia del espesor de la junta de mortero en la resistencia a compresión de la fábrica de ladrillo cerámico bajo esfuerzos de compresión uniaxial. Además se estudia el progresivo agrietamiento del material durante el proceso de carga. Se han ensayado nueve muros y nueve pilares, combinando tres espesores de junta de mortero relizando medidas con ultrasonidos, además se han realizado medidas con extensómetros y esclerómetro. Los resultados obtenidos muestran que a menor espesor de junta mayor carga de rotura y mayor valor de la velocidad de pulso ultrasónico. La medida con ultrasonidos muestra una buena correlación con las medidas extensométricas y permite una eficaz detección del agrietamiento interior del material durante el proceso de rotur

Influencia de las propiedades de la fábrica de la catedral de León en su comportamiento estructural

Mechanical and physical properties of the masonry have a considerable bearing on the structural behaviour. Ancient buildings, like Leon’s cathedral, show uncertainty about real condition of the material and even structural compounds. These uncertainties make it difficult to assessment the bearing capacity of the structure and the affect of the restorations. This paper shows a study to select the most influential material’s parameters on the structural behaviour. The study is based on a sensitiveness analysis.The study starts with a structural analysis to select the most responsible areas of the transversal structural section. Then, the structural calculation is done by modifying the value of the material’s parameters in the expected scatter band. The statistical study provides the most influential parameters on the structural masonry behaviour. Finally the conclusions are proponed.Las propiedades de un material como la fábrica influyen de forma determinante en el comportamiento de la estructura. En una estructura histórica, como la catedral de León, se añade la incertidumbre del estado real del material y la composición de sus elementos estructurales. Estos aspectos dificultan la evaluación de la capacidad resistente de la estructura y la incidencia de actuaciones de reparación o remodelación. Este trabajo presenta el estudio realizado para seleccionar, mediante un análisis de sensibilidad del comportamiento de la estructura, cuáles son las variables del material que más afectan al comportamiento estructural de la catedral.El estudio se inicia con el análisis estructural de la sección tipo para identificar las zonas de mayor responsabilidad. A continuación se hace el estudio estructural con la combinación de todas las variables, especialmente las dependientes de los materiales, modificando su valor. Mediante un tratamiento estadístico de los resultados, se determina qué parámetros de los adoptados afectan más al comportamiento de la estructura de fábrica y se establecen las conclusiones

Evaluación Estructural Mediante Ultrasonidos del Efecto del Espesor de la Junta de Mortero en Muros de Fábrica de Ladrillo Cerámino Sometidos a Esfuerzo de Compresión hasta su Rotura.

En este trabajo se analiza la influencia del espesor de la junta de mortero en el comportamiento estructural de probetas de fábrica de ladrillo cerámico bajo esfuerzos de compresión uniaxial. El ensayo de compresión reproduce la forma habitual de trabajo de estas estructuras. Se han ensayado nueve muros y nueve pilares, combinando tres espesores de junta de mortero, sometidos a carga de compresión hasta rotura. Con el fin de evaluar el progresivo agrietamiento del material durante el proceso de carga, se han realizado medidas con ultrasonidos. Además se han realizado medidas con extensómetros y esclerómetro para contrastar la validez de las medidas de ultrasonidos. Los resultados obtenidos muestran que existe una correlación entre los valores de la fuerza de compresión que soportan las probetas y el tamaño del espesor de la junta: a menor espesor de junta mayor carga de rotura. Del estudio también se desprende que esta relación es más clara en los muros que en los pilares, ya que la esbeltez de los muros es mayor y aparecen efectos de pandeo. La medida con ultrasonidos muestra una buena correlación con las medidas extenso métricas y permite una eficaz detección del agrietamiento interior del material durante el proceso de rotura

Adsorció de l'herbicida Paraquat en Alginat de Calci

La sostenibilitat de l’ús de l’aigua esta lligada de forma fonamental al seu ús en l’agricultura. L’activitat agrària afecta directament la qualitat de les aigües. Els residus de fertilitzants i de productes fitosanitaris, entre ells els herbicides, constitueixen una font de contaminació del sòl, els quals a través de processos d’escorrentia i infiltració alteren la qualitat de diferents masses d’aigua. La detecció de residus d’herbicides i els seus metabòlits en les aigües dels rius i el mar fa que la eliminació d’aquets productes orgànics, molts d’ells tòxics, s’hagi convertit en un dels problemes mediambientals més importants. Per tal de intentar solucionar aquest problema s’han realitzat nombrosos estudis sobre la eliminació d’aquests compostos mitjançant diferents processos, essent uns del més utilitzats el procés d’adsorció. En les últimes dècades, la utilització de biopolímers com adsorbents per la eliminació de compostos orgànics de les aigües residuals ha demostrat ser eficaç [1]. En aquest treball es presenta l’estudi sobre l’adsorció de l’herbicida paraquat en l’alginat de calci, així com l’efecte de la presencia del colorant reactive black 5 (RB5) sobre l’adsorció del paraquat. Hem de tenir en compte que les formulacions comercials contenen a més del propi herbicida altres substancies com els colorants que eviten la confusió amb altres tipus de begudes. El paraquat és altament tòxic i pel fet de estar carregat positivament s’uneix fortament a les argiles del sòl, al humus i altres compostos orgànics que poden estar presents en el sòl, però no s’adsorbeix en terres sorrenques amb baix contingut de matèria orgànica. En aquest últim cas el paraquat pot esser alliberat passant a les aigües circumdants al terreny on s’ha aplicat, per escorrentia o infiltració [2]. Les variables que s’han tingut en compte en l’estudi de la capacitat d’adsorció del paraquat en alginat de calci són: el pH, la concentració inicial de paraquat; la velocitat d’agitació; massa d’adsorbent i la concentració de colorant present en la dissolució. Els resultats obtinguts ens han demostrat que l’alginat de calci és eficaç en l’eliminació del paraquat de les dissolucions aquoses. L’adsorció del paraquat es veu influenciada per el pH. Al augmentar el pH augmenta la capacitat d’adsorció del paraquat. La presència de colorant disminueix l’adsorció del paraquat, conservant-se una reducció del 20 i 24% quan s’addicionen 50 i 100 mg/L, respectivament. En aquest estudi també s’ha realitzat un tractament estadístic dels resultats experimentals, aplicant la tècnica de mínims quadrats parcials (PLS; Partial Least Square) [3-5]. La regressió per mínims quadrats parcials (PLS, Partial Least Squares) fa ser introduïda per Herman Wold (1975) per a ser aplicada a ciències econòmiques i socials, tot i que desprès ha estat aplicada a moltes altres branques científiques. La metodologia PLS generalitza i combina característiques de l’Anàlisi de Components Principals (PCA) i l’Anàlisi de Regressió Múltiple. L’anàlisi PLS és utilitzat quan volem correlacionar un elevat nombre de descriptors (variables independents), amb un determinat nombre de variables dependents. Els càlculs s’han realitzat amb el programa SIMPCA-P [6], fent possible la valoració de la capacitat d’adsorció, la predicció toxicològica i l’impacta ambiental en processos similars.Peer Reviewe

Kinetics of antibodies in sera, saliva, and urine samples from adult patients with primary or secondary dengue 3 virus infections

SummaryObjectivesThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue infection were studied.DesignSerum, saliva, and urine samples were collected from 22 patients with clinical and confirmed dengue 3 virus infection during the outbreak in Havana City in 2001. They were tested by capture IgM (MAC-ELISA), IgA (AAC-ELISA), and IgE (EAC-ELISA) and IgG ELISA inhibition method (EIM) to detect specific dengue antibodies.ResultsSimilar kinetics were observed in IgM, IgA, and IgG antibodies in saliva and IgA and IgG in urine samples from secondary cases compared with kinetics in serum samples, although the values were lower. No IgG antibody was detected in saliva and urine samples in primary cases and IgM antibody was not detected in urine samples from either primary or secondary infection. All secondary cases were positive for IgG in saliva and urine samples at day 7. The kinetics of specific IgE antibodies in primary and secondary cases were different.ConclusionsThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue 3 virus infection were studied for the first time, showing its behavior and usefulness in dengue virus diagnosis. The specific IgE could play a role as a serological marker in secondary infections

Cigarette smoke induces pulmonary arterial dysfunction through an imbalance in the redox status of the soluble guanylyl cyclase

Chronic obstructive pulmonary disease (COPD), whose main risk factor is cigarette smoking (CS), is one of the most common diseases globally. Some COPD patients also develop pulmonary hypertension (PH), a severe complication that leads to premature death. Evidence suggests reactive oxygen species (ROS) involvement in COPD and PH, especially regarding pulmonary artery smooth muscle cells (PASMC) dysfunction. However, the effects of CS-driven oxidative stress on the pulmonary vasculature are not completely understood. Herein we provide evidence on the effects of CS extract (CSE) exposure on PASMC regarding ROS production, antioxidant response and its consequences on vascular tone dysregulation. Our results indicate that CSE exposure promotes mitochondrial fission, mitochondrial membrane depolarization and increased mitochondrial superoxide levels. However, this superoxide increase did not parallel a counterbalancing antioxidant response in human pulmonary artery (PA) cells. Interestingly, the mitochondrial superoxide scavenger mitoTEMPO reduced mitochondrial fission and membrane potential depolarization caused by CSE. As we have previously shown, CSE reduces PA vasoconstriction and vasodilation. In this respect, mitoTEMPO prevented the impaired nitric oxide-mediated vasodilation, while vasoconstriction remained reduced. Finally, we observed a CSE-driven downregulation of the Cyb5R3 enzyme, which prevents soluble guanylyl cyclase oxidation in PASMC. This might explain the CSE-mediated decrease in PA vasodilation. These results provide evidence that there might be a connection between mitochondrial ROS and altered vasodilation responses in PH secondary to COPD, and strongly support the potential of antioxidant strategies specifically targeting mitochondria as a new therapy for these diseasesThe Spanish Ministerio de Ciencia e Innovacion, ´ Programa Retos en Investigacion ´ (grant number PID2019-104406RB-100) to MJC provided the financial support for the conduct of the research included in this manuscript. Garantia Juvenil program from Comunidad de Madrid contributed with the research assistant contract to M-R,

Psychosocial burden in adult patients with atopic dermatitis

P16 Objective: Atopic dermatitis affects patients’ quality of life (QoL) in many ways. It is important to analyze the impact that the disease produces in order to better define the healthcare needs of adult patients with atopic dermatitis. Patients and Methods: 14 adult patients with atopic dermatitis were interviewed. The qualitative interviews were semi-structured and supported by a simple script, which allowed a complete and flexible interview. Results: Six affected areas of the patient’s life with atopic dermatitis were identified: economic, work-related, personal, psychosocial, clinical and relational. It is emphasized that atopic dermatitis has a great psychosocial impact on the adult patient, since it alters interpersonal relationships, generates rejection, stigmatization and social isolation, limits the patient in various areas and activities of their daily life or alters sleep, among others. The visible aspect, the itching-scratching cycle, the lack of awareness and ignorance of the disease, the lack of a definitive solution among the treatments and the side effects of some of them are of great concern. Conclusions: The QoL of the patients with atopic dermatitis is negatively affected and a holistic multidisciplinary intervention is necessary in order to mitigate the negative impact of the disease

Patient reported outcomes (PROS) in psoriasis patients

P20 Introduction: Psoriasis is a chronic skin disease with negative physical, mental and social manifestations. Method: We carried out a longitudinal and prospective study under routine clinical practice conditions. The objective of the study was to measure quality of life with the Short Form-36 Survey (SF-36) and correlate the results with clinical variables using the PASI and BSA in a group of 17 patients with moderate to severe psoriasis treated with Ustekinumab. Results: In the baseline evaluation we observed the following results: 35.3% reported physical malfunction, 64.7% debilitating pain, 82.3% poor health in general, 76.4% bad vitality, 88.2% social malfunction, 100% emotional malfunction and 82.3% poor mental health. At week 78 we observed the following results: 41.15% reported very good physical functioning, 76.1% no pain, 58.8% good general health, 58.8% very good vitality, 70%, 5% good social functioning, 70.5% good emotional functioning and 52.9% good mental health. Conclusion: We observed that the perception of patients with moderate-severe psoriasis regarding their health at the beginning of treatment with Ustekinumab was poor and that they experienced a significant improvement throughout the successive weeks of treatment

A clinical pathway for community-acquired pneumonia: an observational cohort study

<p>Abstract</p> <p>Background</p> <p>Six hospitals instituted a voluntary, system-wide, pathway for community acquired pneumonia (CAP). We proposed this study to determine the impact of pathway antibiotics on patient survival, hospital length of stay (LOS), and total hospital cost.</p> <p>Methods</p> <p>Data were collected for adults from six U.S. hospitals with a principal CAP discharge diagnosis code, a chest infiltrate, and medical notes indicative of CAP from 2005-2007. Pathway and non-pathway cohorts were assigned according to antibiotics received within 48 hours of admission. Pathway antibiotics included levofloxacin 750 mg monotherapy or ceftriaxone 1000 mg plus azithromycin 500 mg daily. Multivariable regression models assessed 90-day mortality, hospital LOS, total hospital cost, and total pharmacy cost.</p> <p>Results</p> <p>Overall, 792 patients met study criteria. Of these, 505 (64%) received pathway antibiotics and 287 (36%) received non-pathway antibiotics. Adjusted means and p-values were derived from Least Squares regression models that included Pneumonia Severity Index risk class, patient age, heart failure, chronic obstructive pulmonary disease, and admitting hospital as covariates. After adjustment, patients who received pathway antibiotics experienced lower adjusted 90-day mortality (<it>p </it>= 0.02), shorter mean hospital LOS (3.9 vs. 5.0 days, <it>p </it>< 0.01), lower mean hospital costs ($2,485 vs.$3,281, <it>p </it>= 0.02), and similar mean pharmacy costs ($356 vs.$442, <it>p </it>= 0.11).</p> <p>Conclusions</p> <p>Pathway antibiotics were associated with improved patient survival, hospital LOS, and total hospital cost for patients admitted to the hospital with CAP.</p