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Effective properties of non-aging linear viscoelastic and hierarchical composites are investigated via a three-scale asymptotic homogenization method. In this approach, we consider the assumption of a generalized periodicity in the different structural levels and their characterization through the so-called stratified functions. The expressions for the associated local and homogenized problems, and the effective coefficients are derived at each level of organization by using the correspondence principle and the Laplace-Carson transform. Considering isotropic components and a perfect contact at the interfaces between the constituents, analytical solutions, in the Laplace-Carson space, are found for the local problems and the effective coefficients are computed. An interconversion procedure between the effective relaxation modulus and the effective creep compliance is carried out for obtaining information about both viscoelastic properties. The numerical inversion to the original temporal space is also performed. Finally, we exploit the potential of the approach and study the overall properties of a hierarchical viscoelastic composite structure representing the dermis. [ABSTRACT FROM AUTHOR]

Seasonal variations have been described in humans in several variables such as sleep, mood, appetite, food preferences, or body weight. We hypothesized that these variations could also influence the decrease in body weight rate in patients submitted to body weight loss interventions. Thus, here we tested the variations of weight loss according to the time of the year the surgery took place in a group patients (n = 1322) submitted to bariatric surgery in the Hospital Universitari de la Vall d'Hebron in Barcelona (geographical coordinates: 41°25ʹ41″N 2°8ʹ32″E). For the analysis, the percentage of total body weight loss (%TWL), excess body weight loss (%EWL) and percentage of body mass index loss (%BMIL) were calculated at 3 (n = 1255), 6 (n = 1172), 9 (n = 1002), and 12 months (n = 1076) after surgery. For %EWL and %BMIL a statistically significant seasonal variation was detected when the variables were calculated at 3 months, but not at the other times, with more weight loss in summer-fall. However, seasonal variations were not detected for %TWL (p = 0.09). The mean amplitude of the seasonal rhythm for %EWL was of 1.8%, while for the rhythm of %BMIL was 0.7%. Moreover, a second peak was detected in January-February modulating the seasonal rhythm of the two variables. Results confirm seasonal variations in humans and indicate that short term responses to weight loss can be modulated by the time of year. [ABSTRACT FROM AUTHOR]

Seasonality is a phenomenon that is characterized by changes over the year in sleep, mood, behaviour, appetite and body weight. In humans, seasonal variations have been found in certain variables, such as lipid variables and body mass index. We hypothesize that this rhythm could influence the expected variation of the levels of biochemical variables in cases of body weight loss. Thus, the goal of this study was to observe whether the time of year in which bariatric surgery (BS) took place modulated the changes in several variables related to glucidic and lipid metabolism. Blood samples were obtained from 24 women and 10 men before BS and 1 and 3 months after BS. We calculated the percentage of variation that occurred for each individual and for each variable as a function of the time of the year. Data were adjusted to a 12-month period sinusoidal curve, with significance being set at p < 0.05. The results showed that almost all of the studied variables changed due to the BS according to a seasonal rhythm. Most of the variables showed a decrease that was most prominent in winter. In the cases of body mass index (BMI), adrenocorticotropin hormone (ACTH), and cortisol, the highest variation occurred in winter. Insulin and cholesterol in high-density lipoproteins (cHLD) variations were higher in springtime. Glucose variation showed a decrease after surgery with acrophase in summer-fall and plasminogen activator inhibitor-1 (PAI-1) and homeostatic model assessment-insulin resistance (HOMA-IR) in spring-summer. Ghrelin levels showed increases with a rhythm of variation with an acrophase in summer-fall. The seasonal rhythm found in this study fits nearly with the inverse of the endogenous circannual rhythm of the variables studied. The time of the year when the highest variation takes place is related to the circannual rhythm of the variable. The results agree with the manifestation of seasonal rhythm in human biochemical variables, which are reflected in the responses to weight loss after BS. [ABSTRACT FROM AUTHOR]

This paper presents a symmetric Kronecker product analysis of independent and identically distributed jump linear systems to develop new, lower dimensional equations for the stability and performance analysis of this type of systems than what is currently available. In addition, new closed form expressions characterising multi-parameter relative sensitivity functions for performance metrics are introduced. The analysis technique is illustrated with a distributed fault-tolerant flight control example where the communication links are allowed to fail randomly. [ABSTRACT FROM AUTHOR]

Epigenetic alterations are associated with cancer and their targeting is a promising approach for treatment of this disease. Among current epigenetic drugs, histone deacetylase (HDAC) inhibitors induce changes in gene expression that can lead to cell death in tumors. Valproic acid (VPA) is a HDAC inhibitor that has antitumor activity at mM range. However, it is known that VPA is a hepatotoxic drug. Therefore, the aim of this study was to design a set of VPA derivatives adding the arylamine core of the suberoylanilide hydroxamic acid (SAHA) with different substituents at its carboxyl group. These derivatives were submitted to docking simulations to select the most promising compound. The compound 2 (N-(2-hydroxyphenyl)-2- propylpentanamide) was the best candidate to be synthesized and evaluated in vitro as an anticancer agent against HeLa, rhabdomyosarcoma and breast cancer cell lines. Compound 2 showed a better IC50 (mM range) than VPA (mM range) on these cancer cells. And also, 2 was particularly effective on triple negative breast cancer cells. In conclusion, 2 is an example of drugs designed in silico that show biological properties against human cancer difficult to treat as triple negative breast cancer. [ABSTRACT FROM AUTHOR]

Purpouse: One Step Nucleic Acid Amplification (OSNA) has been previously proposed for the diagnosis of lymph node metastases (LNMs) from several malignant conditions by quantifying the number of copies of cytokeratin 19 mRNA. Our aim was to evaluate the results obtained by OSNA in the lymph nodes of patients with papillary thyroid carcinoma (PTC) by comparing our results with the findings observed using standard pathological examination. Materials and Methods: Fifty human lymph nodes (from five patients with diagnosed PTC) were studied. Each node was divided into two: one half was used for molecular study ('OSNA-node'), and the other half was used for conventional staining with hematoxylin and eosin ('HE-non-OSNA node'). Three cytological imprints using Papanicolaou and May-Grunwald-Giemsa strains were obtained from both node halves. The results from each technique were compared, and ROC analysis was performed. Results: The OSNA study showed 22 positive samples for LNM (44%), which demonstrate a high concordance rate with the results observed using conventional pathological examination (cytology of 'OSNA-node' and HE of 'Non-OSNA node') with specificity and sensitivity values greater than 86% and 89%, respectively. However, both comparisons differed in the number of copies of mRNA as the best cut-off (260 copies in the first case and 93 in the second case). Conclusions: The OSNA results for the detection of LNM in patients with PTC are comparable with those observed using conventional techniques. However, its quantitative nature could be useful to more accurately detect lymph node involvement. [ABSTRACT FROM AUTHOR]

Antibiotics are pharmaceutical compounds widely used to treat a broad range of infections. These chemicals appear to be recalcitrant compounds when released to water systems, and their presence at the effluent of wastewater treatment plants and surface waters has been widely documented. Sulfamethoxazole (SMX), a sulfonamide commonly used to treat urinary infections, is one of them. Ozonation was proved to be a suitable method to remove SMX antibiotic in water. However, it is stated that a high ozone dosage would be necessary to achieve the complete mineralization of the intermediates. In this work, ozonation is coupled with a Sequencing Batch Biofilm Reactor (SBBR) in order to completely degrade SMX and its metabolites from water solutions. Moreover, a precise description of the microbial community in the bioreactor is provided by means of traditional microscopy and molecular biology techniques. The results obtained showed high Total Organic Carbon removals at the end of the biological treatment (89% removal). Furthermore, nitrates produced during the aerobic SBBR's performance were monitored and eliminated by adding an anoxic stage, achieving an overall nitrogen removal of 86%. A bacterial community analysis of the SBBR during aerobic and aerobic-anoxic conditions was performed, targeting the bacterial 16S ribosomal ribonucleic acid (rRNA) gene. These results revealed a dominant contribution of bacteria from the Proteobacteria class, with a major contribution from theRhizobiales and Burkholderialesorders during the bioreactor performance, counting 52% of the total population. [ABSTRACT FROM AUTHOR]

Fliess operators, which are a type of functional series expansion, have been used to describe a broad class of nonlinear input–output maps driven by deterministic inputs. But in most applications, a system's inputs have noise components. This paper has three objectives. The first objective is to show that the notion of a Fliess operator can be generalized to admit a class of L 2-Itô stochastic input processes. The next objective is to show that they converge absolutely over an arbitrarily large but finite time interval when a certain coefficient growth condition is met. However, a significant number of systems fail to meet this condition. Thus, the final objective is to consider an interval of convergence having a random length so that a Fliess operator might converge under less restrictive growth conditions. [ABSTRACT FROM AUTHOR]

On 2002, a novel initiative was undertaken by the local water administration of Catalonia (the Agència Catalana de l'Aigua) and the Universitat Autònoma de Barcelona, leading to a ten-year project where a high number of medium resolution satellite images (MODIS and Landsat) were integrated to the daily water management to improve decision making effectiveness. This paper describes the methodology followed in the successful application of remote sensing, as well as the main problems that had to be overcome during its execution. It also presents the products that have been calculated. These are integrated into the Agency's corporate GIS and immediately available via the intranet for the staff, and a selection is available on the Internet. [ABSTRACT FROM AUTHOR]

The study aim was to correlate malnutrition and early death in children with acute lymphoblastic leukemia (ALL). A study was conducted in 100 consecutive children with ALL. An analysis included clinical and laboratory parameters as well as co-morbidity factors. Forty patients were standard risk and 60 high risk. Multivariate analysis showed variables of statistical importance, including female gender (p 010), ALL high-risk (p 04), and infection (p 036). Malnutrition (p 1.0) and poverty (p 0.5) did not influence. Early mortality was documented in 15/100 (15%) patients. The study shows that high-risk ALL and infection represent the leading causes of early mortality. [ABSTRACT FROM AUTHOR]

The objective of this work was to modify the simulation mesh model characteristics (critical areas evaluation, mesh density, and elements size) of a commercial compact disk (CD) case by using computer-aided design (CAD) and computer aided engineer (CAE) software. The designing process was carried out by studying the geometry and dimensions of the three pieces (cover, holder, and base) that form commercial and optimized CD cases. The mesh model was obtained using 3D (three dimensional) modeler software and the simulation results were obtained using a simulation program typically used for the injection-molding process. The exposed designs were evaluated and different mesh model characteristics were established. The filling time, cycle time, and residual stress concentration seemed to be influenced by the nodes number model. An analysis of the results of the simulations showed remarkable differences when a high number of nodes in the mesh model were used. [ABSTRACT FROM AUTHOR]