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Tissue barrier permeability plays a crucial role in determining the selective transport of substances across epithelial tissues, including drugs, cosmetic substances, and chemicals. The ability of these substances to cross through tissue barriers affects their absorption into the bloodstream and ultimately their effectiveness. Therefore, the determination of their permeability on these type of tissue barriers represents a useful tool for pharmaceutical and cosmetic industries as well as for toxicological studies. In this regard, microfluidic devices and organ-on-chip technologies are becoming more important to generate reliable data. We have designed and performed an alternative new stratified epithelia-on-chip model that allows to correlate the Stokes radius and the diffusion of molecules and/or nanoformulations through the in vitro generated barrier and establish a system suitable for the analysis of diffusion through stratified epithelium. Thus, extrapolating from experimental data we can predict the Stokes radius for unknown fluorescent labelled particles within a molecular size range, such as gold nanoparticles. [ABSTRACT FROM AUTHOR]

The helminth communities of Extremeña Azul breed chickens (Gallus gallus) have been studied from south-western free-ranging farms in Spain. Two farming systems were compared: a rainfed system and an irrigated system. Necropsy was applied to the animals to compare the structure, biodiversity, and evolution of helminth communities as well as to determine the correlation between parasite burden and chicken weight. 12 species of parasites were identified: 7 cestodes (Raillietina echinobothrida, R. tetragona, Skrajabinia cesticillus. Echinolepis carioca, Davainea proglottina, Amoebotaenia cuneata and Choanotaenia infundibulum), and 5 nematodes (Heterakis gallinarum, Ascaridia galli, Baruscapillaria obsignata, Eucoleus annulatus, and Aonchotheca caudinflata). Cestode prevalence was 54% in the rainfed system whereas it was 98% in the irrigated system; nematode prevalence was 100% in both communities. There were 2 core species in the rainfed and 5 in the irrigated system. The rainfed community showed lower species richness and more dominance. In the irrigated system, the helminth community showed higher biodiversity than in the rainfed system community. This could be attributed to the abundance of intermediate hosts due to irrigation. This study provides data on the distribution of chicken helminths in south-western Europe and the influence of the farming system on their biodiversity. Helminth communities of free-ranging chickens from two different organic agrosystems (irrigated and rainfed) are compared in southern Spain. The irrigated system showed the highest prevalence of helminths. Eucoleus annulatus was only observed in this system with a prevalence of 98%. This is the first study carried out in Spain about this issue. It may be of interest to poultry organic farmers. [ABSTRACT FROM AUTHOR]

Background:Diagnosis of pneumonia in ventilated patients is challenging due to the lack of specific and definitive clinical symptoms, laboratory data or radiological abnormalities. Methods:Based on quantitative tracheal aspirate (QTA) results, three groups of patients were compared: <105 cfu/ml, ≥105 cfu/ml and <106 cfu/ml, and ≥106 cfu/ml. We recorded demographic variables, underlying diseases and severity of illness at ICU admission. On the day of pneumonia diagnosis, we registered temperature, leukocyte count, C-reactive protein, Sequential Organ Failure Assessment (SOFA) score, clinical pulmonary infection score (CPIS) and adequacy of empirical antimicrobial therapy. Results:In 231 episodes, clinical presentation, laboratory data, severity of illness, CPIS, the presence of bacteremia and radiological score did not differ among the three groups. ICU and hospital mortalities were also similar in the three groups. Factors independently associated with in-hospital mortality were age, SOFA score and inappropriate antimicrobial therapy. The bacterial burden in the QTA was not included in the model. Conclusions:Quantification of tracheal aspirate samples may not be necessary in ventilated patients clinically suspected of having nosocomial pneumonia [ABSTRACT FROM AUTHOR]

Objectives: To describe a case diagnosed with intracranial teratoma in week 32 of gestation, as well as review of the literature in order to discern the appropriate treatment method and general prognosis of this anomaly.Methods: A literature search was performed on the prenatal diagnosis of congenital intracranial teratomas in MEDLINE, EMBASE, Cochrane library data bases. Evaluated in this review are parameters such as time of prenatal diagnosis, associated pathology, size of tumors, method of terminating pregnancy, perinatal outcome and histological study of the tumor.Results: A total of 49 cases were found, of which 12 were finished gestation, 28 cesarean section was performed and only nine had vaginal delivery. All died in the neonatal period except in three cases with intrauterine death after diagnosis.Conclusion: As the incidence of intracranial immature teratomas is very low and the prognosis is poor, their prenatal diagnosis and obstetric management present a great challenge for the planning of a follow-up and treatment of the disease in accordance with the preferences of the parents. [ABSTRACT FROM AUTHOR]

Different carbon allotropes, including vulcan carbon, multiwall carbon nanotubes, graphene, and nanodiamonds, were processed by chemical purification and treated in a mixture of H2SO4–HNO3. The materials were characterized by infrared and Raman spectroscopy as well as by scanning and transmission electron microscopy. Oxidative differences are indicated by Raman through the G band (∼1570 cm−1), D band (∼1340 cm−1), and G’ band (∼2684 cm−1). The crystal size (La) and purity, relative to the amorphous carbonaceous material, were studied as well, along with the morphological changes induced by the treatments. [ABSTRACT FROM PUBLISHER]

Adding P onLotus tenuisandFestuca arundinacea, pure or mixed, on growth, nitrogen (N) and phosphorus (P) acquisition and associations with soil microorganisms was studied to investigate the establishment ofLotusfor competing withFestuca. Triple-superphosphate was applied on a Typic Natraquoll whereLotusgrows spontaneously. Biomass, N-P uptake, arbuscular mycorrhizal colonization and rhizobia nodulation were measured.Lotusachieved the highest biomass, N-P uptake in fertilized stands andFestucathe lowest in fertilized and non-fertilized stands. Mycorrhizal colonization decreased with P-fertilization in both plants. Rhizobia nodules inLotusshowed little changes with P-fertilization. In mixed fertilized-stands,Lotuspromoted the growth, N-P uptake ofFestuca. P-fertilization increases the ability ofFestucato compete withLotusfor available-P in soil.Lotusimproves nutrient cycling, maintains high level of rhizobia nodules and arbuscular mycorrhizal colonization in roots. Adding P to limited N-P environments depress grasses growth to compete with legumes for resources. [ABSTRACT FROM AUTHOR]

The investigated slow sliding speeds presented in this work enable the understanding of the wear behavior on aluminum alloys and could possibly facilitate the completion of the previously proposed wear mechanism map for aluminum at this slow sliding speed range. Dry sliding block-on-ring wear tests were carried out on aluminum alloys, AA5754 (Al-Mg), AA6082 (Al-Mg-Si), and AA7075 (Al-Zn-Cu), at a very slow sliding speed range (<0.01 m/s). A bearing steel ring of AISI 52100 was used as the counterbody. Tests were performed at varying contact pressures, 20, 100, and 140 MPa, and sliding speeds ranging from 0.001 to 1.5 m/s. The wear tracks and debris collected were examined by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD), with the aim of analyzing their morphology and composition. At relatively slow sliding speeds (>0.01 m/s), the specimens exhibited a wear process placed at the mild wear regime, characterized by oxidation and delamination mechanisms of both the aluminum specimen and the steel ring. However, at very slow speed range (<0.01 m/s), an increase in the wear rate and the friction coefficient is observed for all of the aluminum alloys, thus suggesting that an alternative wear mechanism could be taking place. [ABSTRACT FROM PUBLISHER]

The influence of the lyophilization process on the recovery of ten organochlorine compounds, (9 polychlorinated biphenyls (PCBs) and pp′-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene)] during the pretreatment step of mussels was studied at three concentration levels. Losses of more polar and water-soluble compounds were approximately 50% in samples pulverized prior to lyophilization. Two variables, moisture and lipid concentrations, had statistical influences in the losses of the lower chlorinated compounds (CB 31 and CB 28). In some PCB congeners (CB 52, CB 101, and CB 118), the variation of losses with the PCB concentrations was also statistically significant. [ABSTRACT FROM AUTHOR]

At the present time one of the most ‘desirable’ behavioural addictions that any person could develop is workaholism, a negative psychological state characterized by working excessively and compulsively. In our society, the successful person is one who spends all of their time working. Moreover, a common pattern of company management consists of stressing and putting pressure on employees to achieve the maximum profit. This trend has increased with the economic crisis in Spain and over the world. As a consequence, the terms hard working and workaholism are easily confounded, but their effects on the companies are highly different in terms of productivity. This paper proposes a discrete mathematical model to forecast the development of workaholism in Spain in the next years. A questionnaire is used in order to measure and classify our sample in subpopulations by their level of addiction. Then, different economic scenarios are simulated. Finally, economic and social consequences of this addiction are studied and public health recommendations are suggested. [ABSTRACT FROM PUBLISHER]

We consider a class of problems where a given number p of facility locations must be selected from a set of s potential locations so as to optimize a pre-determined fitness function. There exist outstanding location problems in this class, such as the p-median, max-covering, MAXCAP, and MAXPROFIT problems. These location problems may contain more than a single global optimal solution. Obtaining multiple global optimal solutions allows us to consider other characteristics in the process of selecting the preferred solution. In [B. Pelegrin, J. Redondo, P. Fernandez, I. Garcia, and P. Ortigosa, GASUB: Finding global optima to discrete location problems by a genetic-like algorithm, J. Glob. Optim. 38 (2007), pp. 249-264], a new 'multimodal' algorithm (gasub) was presented for solving the previously mentioned location problems. In the paper, the algorithm was fine-tuned to obtain a single global optimum (with 100% success) as fast as possible, and it was compared with two widely used techniques, that is, the standard optimizer Xpress-MP [Xpress-MP, Dashoptimization, 2004.] and the Multi Start Heuristic. In this paper, we propose a new set of parameter values so that gasub can explore the space more deeply and consequently find several alternative global optimal solutions. Moreover, two coarse-grain parallelizations of gasub are presented, cggasub and cggasub_mo. cggasub is able to reduce the computational time of gasub where solutions of the same quality are generated, while cggasub_mo finds more alternative global optima than the sequential version and spending similar computational time in the process. gasub, with the new parameter setting and also the parallel algorithms, will be evaluated using a comprehensive computational set of experiments. Additionally, some criteria can also be used to select one of the known global optimal solutions when several alternatives optimize the corresponding objective function. [ABSTRACT FROM AUTHOR]

The focus of this paper is on the analysis and evaluation of a type of parallel strategies applied to the algorithm Advanced Multidimensional Interval analysis Global Optimization (AMIGO). We investigate two parallel versions of AMIGO, called Parallel AMIGO (PAMIGO) algorithm, Global-PAMIGO and Local-PAMIGO. The idea behind our study is that in order to exploit the potential parallelism of algorithms, researchers need to adapt them to the target computer architectures. Our PAMIGO algorithms have been designed for shared memory architectures and are based on a threaded programming model, which is suitable to be run on current personal computers with multicore processors. Our first experimental results show a promising speed-up up to four process units. We analyse the loss of efficiency when the number of process units is greater than four by obtaining a profile of the algorithm executions. Secondly we experiment with the use of a local memory allocator per thread. This increases the efficiency by reducing the number of lock conflicts given by the standard system memory allocator. Our experimental results for both PAMIGO versions, using up to 15 process units, obtain a good performance for hard to solve problems on unicore and multicore processors. It is noteworthy that both versions of PAMIGO obtain a similar performance. Our experiments may be useful for researchers who use parallel B&B algorithms. [ABSTRACT FROM AUTHOR]

To establish polychlorinated biphenyl (PCB) levels and distribution as well as their relationship to biometric parameters in the razor clam Ensis siliqua (Linnaeus, 1758), 15 individual samples collected from two points sited in the Islas Cies, Ría de Vigo in Galicia, Spain, collected monthly between February 2003 and April 2004, were analysed. PCBs (IUPAC No. 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180) were isolated by Soxhlet extraction. Identification and quantification were performed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography (electron capture detector), respectively. The isomer concentrations in E. siliqua were in the order hexachlorobiphenyls > pentachlorobiphenyls > heptachlorobiphenyls > trichlorobiphenyls > tetrachlorbiphenyls. No correlation was observed between the E. siliqua shell length and PCBs levels. The PCBs 31, 101, 105 and 153 levels were statistically related with some biometric parameters (p < 0.05). Multivariate techniques such as principal component analysis (PCA) show clear seasonal differences between samples. [ABSTRACT FROM AUTHOR]

An improvement to a current methodology for testing iterative reconstruction algorithms is presented. This modification consists of the use of a multidimensional global optimization algorithm for the best estimate of the free parameters of the reconstruction process. This algorithm is based on a probabilistic random search method. This tool allows the best performance of the reconstruction algorithms to be to obtained without any prejudice in the parameter selection. This methodology has been applied to testing an algebraic reconstruction technique (ART) algorithm performance using classical cubic-shaped voxels and spherical symmetric basis functions, also known as blobs, as the basis functions for image representation in three-dimensional X-ray cone-beam transmission tomography. [ABSTRACT FROM AUTHOR]

The authors analyze two direct methods for solving the symmetric eigenproblem of large and sparse matrices in terms of their parallel implementations. Their proposals provide efficient parallel solutions for problems with large computational requirements. The direct solutions were decomposed in the following phases: (1) structuring the input matrix--the Lanczos method with complete reorthogonalization was implemented for this stage; (2) solving the eigenproblem of a structured matrix--two methods were applied to solve this stage, bisection and inverse iteration methods, and the divide-and-conquer method; (3) computing the eigenvectors of the input matrix, carried out by a matrix-matrix product. These methods have been implemented on a multiprocessor system and their performance evaluations carried out on a Cray T3E system with up to 32 nodes. Results show that the management of the memory hierarchy improves substantially as the number of processors increases, and that this is one of the reasons why superlinear speedups are obtained. [ABSTRACT FROM AUTHOR]

Thallium content and chemical speciation was studied at 91 sites contaminated by water and tailings spilled from the settling pond of a pyrite mine into the Agrio and Guadiamar rivers in Aznalcóllar (Spain). The contamination was highly heterogeneous, with 15% of the affected area seriously contaminated, 55% moderately contaminated and 30% uncontaminated. The total Tl content in the surface horizon increased with respect to the background level, more limit 4-fold in the uppermost 10 cm of the soils, and clearly decreased with depth without contaminating either the subsoil or groundwater. Must of the Tl (approximately 75%) was in non-extractable forms, either as a component of the particles in the tailing or adsorbed to crystalline oxides. The remaining Tl was held on, or occluded in, amorphous or poorly crystallised oxides. In acidic soils, the adsortion of Tl was dominated by iron oxides (Feo) and, in neutral-alkaline soils, by aluminium oxides (Alo). A relatively high amount of the Tl adsorbed by amorphous oxides in the uppermost 10 cm of the soils was extracted with acetic acid, and was presumably bio-available (mean values approximately 15% of the Tlo). The EDTA is a strong extractant of inorganic forms aluminium and, consequently, the quantity of Tl extracted by EDTA in neutral-alkaline soil (mean values more than 10% of the total Tl) could be higher than the truly bio-available fraction. Approximately 1% of the total Tl wan extracted with calcium chloride, hut only in the neutral-alkaline soil was the exatration significantly related to the cation-exchange capacity and. thus, adsorbed by the negative charges of the clay and organic matter. The Tl soluble in water (<1%) declined with the pH in the neutral-alkaline soils, and was unrelated to any soil property in the acid soils. Tints, the behavior of Tl is determined by climatic conditions, soils properties and time. [ABSTRACT FROM AUTHOR]

Studies the levels and distribution patterns of polychlorinated biphenyl (PCB) congeners in surface sediments from Galicia Coast, northwestern Spain according to granulometric characteristics. Isolation of different PCB by Soxhlet extractions from three fractions of different particle size; Total organic carbon and PCB content relation; Grain size and relation PCB content.