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1.
Sci Total Environ ; 849: 157828, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-35934022

RESUMEN

External Thermal Insulation Composite Systems (ETICS) are multilayer solutions which provide an enhanced thermal performance to the building envelope. However, significant anomalies can be detected on ETICS facades, in some cases shortly after the application of these systems. This study intends to evaluate and compare the durability of six commercially available ETICS after two years of outdoor exposure at both urban and maritime conditions in Portugal. The systems were characterized by means of non-destructive testing (i.e., visual and microscopic assessment, water transport properties, thermal conductivity, surface roughness), thus allowing to evaluate the performance loss throughout natural aging. The bio-susceptibility and aesthetic properties (color and gloss) were also investigated. Results showed that the performance and durability of the complete system is significantly affected by the rendering system formulation. The lime-based specimens obtained the highest rate of mold development after one year of aging in a maritime environment, becoming considerably darker and with lower surface gloss. Fungal analysis of this darkish stained area indicated the presence of mold species of the genera Alternaria, Didymella, Cladosporium and Epicoccum, and yeasts of the genera Vishniacozyma and Cystobasidium. An increase of both capillary water absorption and water vapor permeability was also registered for the aged lime-based specimens. Acrylic-based systems obtained lower capillary water absorption after aging and greater dirt deposition on their surfaces, especially in urban conditions. These systems had also higher color variation and surface gloss decrease and slightly higher mold growth, when compared with those aged in a maritime environment. Finally, no mold growth was detected on the silicate-based specimens after two years of aging. However, these specimens obtained higher capillary water absorption and lower vapor permeability after aging, possibly leading to moisture accumulation within the system. Results contribute towards the development of ETICS with enhanced performance and durability.


Asunto(s)
Resinas Compuestas , Vapor , Compuestos de Calcio , Ensayo de Materiales , Óxidos , Propiedades de Superficie
2.
J Phys Condens Matter ; 33(6): 065704, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33137791

RESUMEN

We present a mixed-lattice atomistic kinetic Monte-Carlo algorithm (MLKMC) that integrates a rigid-lattice AKMC approach with the kinetic activation-relaxation technique (k-ART), an off-lattice/self-learning AKMC. This approach opens the door to study large and complex systems adapting the cost of identification and evaluation of transition states to the local environment. To demonstrate its capacity, MLKMC is applied to the problem of the formation of a C Cottrell atmosphere decorating a screw dislocation in α-Fe. For this system, transitions that occur near the dislocation core are searched by k-ART, while transitions occurring far from the dislocation are computed before the simulation starts using the rigid-lattice AKMC. This combination of the precision of k-ART and the speed of the rigid-lattice makes it possible to follow the onset of the C Cottrell atmosphere and to identify interesting mechanisms associated with its formation.

3.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1555-1560, July-Aug. 2020. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1131472

RESUMEN

Este trabalho descreve um surto de rumenite e abomasite decorrente de sobrecarga de carboidratos em um rebanho de 238 bezerros, com idades entre 12 e 15 meses, causada pela ingestão dos frutos de Enterolobium contortisiliquum. As taxas de morbidade, mortalidade e letalidade foram de, respectivamente, 12,7%, 5,2% e 42,1%. Clinicamente, os bovinos apresentaram fotossensibilização, salivação e diarreia. Os achados de necropsia foram semelhantes nos dois bezerros necropsiados e consistiram de fotodermatite e rumenite ulcerativa multifocal, subaguda a crônica, e abomasite. A relevância deste relato é que, pela primeira vez, foi possível associar a ocorrência da rumenite devido à sobrecarga de carboidratos com a intoxicação espontânea por E. contortisiliquum em bovinos, confirmando achados anteriormente descritos em experimentos realizados com ovinos.(AU)


Asunto(s)
Animales , Bovinos , Intoxicación por Plantas/veterinaria , Rumen/patología , Acidosis/veterinaria , Abomaso/patología , Trastornos por Fotosensibilidad/veterinaria , Plantas Tóxicas , Fabaceae/toxicidad
4.
J Phys Condens Matter ; 30(33): 335901, 2018 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-29989564

RESUMEN

A static and kinetic study of the interaction between a 19 ½ 〈1 1 1〉 self-interstitial atoms loop and C atoms in body-centred cubic iron is presented in this work. An empirical potential matching the density functional theory calculations is used to study the static properties of the system. The usual kinetic Monte-Carlo (KMC) on-lattice restriction is not valid when the material is highly distorted, especially in the presence of a dislocation loop. Therefore, the dynamics of the system are investigated using both molecular dynamics simulations and k-ART, a self-learning/off-lattice atomic kinetic monte-carlo. The presented work is thus a full study of the C-loop and the C2-loop systems. A good agreement is observed between the statics and the kinetics (e.g. the discovery of a zone of stability of the C atom around the Fe cluster where the C can almost freely move), even though the kinetics show some unexpected behaviours of the studied systems. The pinning time of the loop induced by the C atoms is also estimated.

5.
Pharmacogenomics J ; 18(2): 301-307, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28485375

RESUMEN

Efficacy and toxicity of anthracycline treatment in acute myeloid leukemia (AML) is mediated by reactive oxygen species (ROS). NADPH oxidase is the major endogenous source of ROS and a key mediator of oxidative cardiac damage. The impact of NADPH oxidase polymorphisms (CYBA:rs4673, NCF4:rs1883112, RAC2:rs13058338) was evaluated in 225 adult de novo AML patients. Variant alleles of NCF4 and RAC2 were related to higher complete remission (P=0.035, P=0.016), and CYBA homozygous variant showed lower overall survival with recessive model (P=0.045). Anthracycline-induced cardiotoxicity was associated to NCF4 homozygous variant (P=0.012) and CYBA heterozygous genotype (P=0.027). Novel associations were found between variant allele of CYBA and lower lung and gastrointestinal toxicities, and a protective effect in nephrotoxicity and RAC2 homozygous variant. Moreover, RAC2 homozygous variant was related to delayed thrombocytopenia recovery. This study supports the interest of NADPH oxidase polymorphisms regarding efficacy and toxicity of AML induction therapy, in a coherent integrated manner.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioterapia de Inducción/métodos , Leucemia Mieloide Aguda/genética , NADPH Oxidasas/genética , Polimorfismo de Nucleótido Simple/genética , Anciano , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Persona de Mediana Edad , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Inducción de Remisión/métodos , Estudios Retrospectivos , Proteínas de Unión al GTP rac/genética , Proteína RCA2 de Unión a GTP
6.
Bone Marrow Transplant ; 50(11): 1465-72, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26281032

RESUMEN

Studies that analyze the epidemiology and risk factors for invasive fungal disease (IFD) after engraftment in alloSCT are few in number. This single-center retrospective study included 404 alloSCT adult recipients surviving >40 days who engrafted and were discharged without prior IFD. All patients who received ⩾20 mg/day of prednisone were assigned to primary oral prophylaxis (itraconazole or low-dose voriconazole). The primary end point was the cumulative incidence (CI) of probable/proven IFD using the European Organization for Research and Treatment of Cancer and Mycoses Study Group (EORTC/MSG) criteria. The independent prognostic factors after multivariate analyses were used to construct a post-engraftment IFD risk score. The 1-year CI of IFD was 11%. The non-relapse mortality was 40% in those developing IFD and 16% in those who did not. The intent-to-treat analysis showed that 17% of patients abandoned the assigned prophylaxis. Age >40 years, ⩾1 previous SCT, pre-engraftment neutropenia >15 days, extensive chronic GVHD and CMV reactivation were independent risk factors. The post-engraftment IFD score stratified patients into low risk (0-1 factor, CI 0.7%), intermediate risk (2 factors, CI 9.9%) and high risk (3-5 factors, CI 24.7%) (P<0.0001). The antifungal prophylaxis strategy failed to prevent post-engraftment IFD in 11% of alloSCT. Our risk score could be useful to implement risk-adapted strategies using antifungal prophylaxis after engraftment.


Asunto(s)
Antifúngicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Micosis/epidemiología , Premedicación , Triazoles/uso terapéutico , Administración Oral , Adulto , Anciano , Aloinjertos , Anfotericina B/uso terapéutico , Antifúngicos/administración & dosificación , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergilosis/etiología , Caspofungina , Causas de Muerte , Quimioterapia Combinada , Equinocandinas/uso terapéutico , Femenino , Fungemia/tratamiento farmacológico , Fungemia/epidemiología , Fungemia/etiología , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neoplasias Hematológicas/terapia , Humanos , Huésped Inmunocomprometido , Incidencia , Lipopéptidos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Micosis/tratamiento farmacológico , Micosis/etiología , Micosis/prevención & control , Neutropenia/prevención & control , Cooperación del Paciente , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Acondicionamiento Pretrasplante/efectos adversos , Insuficiencia del Tratamiento , Triazoles/administración & dosificación , Adulto Joven
7.
J Phys Condens Matter ; 25(2): 025401, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-23178683

RESUMEN

Atomistic simulations with an EAM interatomic potential were used to evaluate carbon-dislocation binding energies in bcc iron. These binding energies were then used to calculate the occupation probability of interstitial sites in the vicinity of an edge and a screw dislocation. The saturation concentration due to carbon-carbon interactions was also estimated by atomistic simulations in the dislocation core and taken as an upper limit for carbon concentration in a Cottrell atmosphere. We obtained a maximum concentration of 10 ± 1 at.% C at T = 0 K within a radius of 1 nm from the dislocation lines. The spatial carbon distributions around the line defects revealed that the Cottrell atmosphere associated with an edge dislocation is denser than that around a screw dislocation, in contrast with the predictions of the classical model of Cochardt and colleagues. Moreover, the present Cottrell atmosphere model is in reasonable quantitative accord with the three-dimensional atom probe data available in the literature.


Asunto(s)
Carbono/química , Hierro/química , Modelos Químicos , Modelos Moleculares , Simulación por Computador , Transferencia de Energía , Presión
8.
Neuroradiol J ; 24(2): 249-52, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24059615

RESUMEN

Superficial siderosis of the central nervous system (CNS) is a rare entity characterized by the deposition of hemosiderin in the leptomeninges. In most cases it is caused by chronic and recurrent bleeding into the subarachnoid space as a subclinical form and for long periods of time. The cases described in the literature are associated with tumors, aneurysms, arteriovenous malformations, changes in post-surgical, traumatic cervical and brachial plexus injuries. However, the cause of bleeding is unclear in 40-50% of cases. This report describes the case of a 38-year-old man with a history of trauma with a complete lesion of the left brachial plexus. The patient presented progressively worsening gait imbalance, bilateral deafness, tinnitus and memory loss over two years. Neurological examination disclosed bilateral hearing loss, left upper limb plegia with atrophy of muscle mass, spastic paraparesis with pyramidal signs and gait ataxia. The analytical/genetic study was consistent with hereditary hemochromatosis. In addition to typical findings of siderosis, MR disclosed pseudomeningocele while CT angiography and angiography revealed an aneurysm of the internal carotid artery. Although rare, we should be aware of superficial siderosis especially in imaging studies in patients with deafness or ataxia and in those with lesions of the brachial plexus. The imaging signals are subtle and can easily go unrecognized. The radiological investigation must be extensive to find the primary cause.

9.
Rev Inst Med Trop Sao Paulo ; 36(2): 171-4, 1994.
Artículo en Portugués | MEDLINE | ID: mdl-7997795

RESUMEN

A case of nasofacial zygomycosis in a 64-year-old female patient from Barcarena, State of Pará, is reported. This is the second time that the disease is recognized in Northern Brazil. The diagnosis was initially suspected by the direct observation of broad coenocytic hyphae in biopsy specimens of the nasal cavity mucosa. Later, the cause of the disease was confirmed by the mycologial and histopathological findings. Rapid response to the therapy with potassium iodide was achieved, without however a complete resolution of the lesions. The patient still remains under treatment, with itraconazole and iodide.


Asunto(s)
Dermatosis Facial/patología , Mucormicosis/patología , Brasil , Quimioterapia Combinada , Dermatosis Facial/tratamiento farmacológico , Femenino , Humanos , Itraconazol/uso terapéutico , Persona de Mediana Edad , Mucorales/aislamiento & purificación , Mucormicosis/tratamiento farmacológico , Mucosa Nasal/microbiología , Yoduro de Potasio/uso terapéutico
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