Modelization of anaerobic processes during co-digestion of slowly biodegradable substrates.

The influence of the soluble substrates over the anaerobic processes has been extensively investigated, but little is known about the effects of particulate substrate. The biodegradation of these substrates starts with the hydrolytic step, this process is slower than the other ones involved in the biodegradation of particulate substrates and usually becomes the rate-limiting step. This study investigate the effect of the initial total solids (TS) concentration on the anaerobic co-digestion of two slowly biodegradable organic substrates. The wastes mixtures were prepared at different dilutions in the range from 10% to 28% TS. From these experiments it was observed that as TS concentration increased, the methane production decreased. These results were modelled and it was observed that neither hydrolysis nor fermentation stages controlled the methane production rate. Being a substrate inhibition event experienced at the methanogenic stage the responsible of the lower methane production when operating at high TS concentrations.

Modeling and simulation of different and representative engineering problems using Network Simulation Method.

Mathematical models simulating different and representative engineering problem, atomic dry friction, the moving front problems and elastic and solid mechanics are presented in the form of a set of non-linear, coupled or not coupled differential equations. For different parameters values that influence the solution, the problem is numerically solved by the network method, which provides all the variables of the problems. Although the model is extremely sensitive to the above parameters, no assumptions are considered as regards the linearization of the variables. The design of the models, which are run on standard electrical circuit simulation software, is explained in detail. The network model results are compared with common numerical methods or experimental data, published in the scientific literature, to show the reliability of the model.

[Study of the diagnostic agreement on headaches between neurology and primary care]. / Estudio de concordancia diagnostica en cefalea entre neurologia y atencion primaria.

INTRODUCTION: Headache as a symptom is a very common disease and one of the main reasons for consultation in primary care. AIM: To analyze the characteristics of patients referred from primary care to general neurology whose chief complaint was headache and/or neuralgia and diagnostic agreement. PATIENTS AND METHODS: Cross-sectional study of all patients referred from primary care; demographic/clinical variables were collected and diagnostic hypothesis by primary care and general neurology were compared by determining their agreement. RESULTS: 2,514 were referred from primary care patients (588 of them on a preferential basis); in 378 cases the reason for consultation was headache and/or neuralgia (average 42.46 years; 77.8% female). In 139 patients it was established only a semiological diagnostic and other episodic migraine predominated (49.79%), chronic tension headache (18.41%) and trigeminal neuralgia (12.13%). Since general neurology, the most common diagnoses were, respectively, 33.86%, 24.05% and 18.67%. A compatible kappa coefficient of 0.543 (p < 0.05) with a moderate agreement when considering only those patients referred from primary care to a specific diagnosis was obtained. CONCLUSIONS: Headaches are a very common reason for consultation in primary care (15%). The diagnostic agreement is moderate in our health sector so it is necessary to design training programs to help outline the criteria for referral to specialists and improve care for our patients.

TITLE: Estudio de concordancia diagnostica en cefalea entre neurologia y atencion primaria.Introduccion. La cefalea como sintoma es una patologia frecuente y uno de los principales motivos de consulta por parte de atencion primaria. Objetivo. Analizar las caracteristicas de los pacientes derivados desde atencion primaria a la consulta de neurologia general con cefalea o neuralgia como motivo de consulta, y la concordancia diagnostica. Pacientes y metodos. Estudio descriptivo transversal de todos los pacientes remitidos desde atencion primaria; se recogieron variables demograficas/clinicas y se compararon las hipotesis diagnosticas de atencion primaria y neurologia, determinando su concordancia. Resultados. Se remitieron desde atencion primaria 2.514 pacientes (588 de ellos con caracter preferente); en 378 casos el motivo de la consulta fue cefalea o neuralgia (42,46 años de media; el 77,8%, mujeres). En 139 pacientes se establecio tan solo un diagnostico semiologico y en el resto predominaron la migraña episodica (49,79%), la cefalea tensional cronica (18,41%) y la neuralgia del trigemino (12,13%). Desde neurologia, los diagnosticos mas frecuentes fueron, respectivamente, 33,86%, 24,05% y 18,67%. Se obtuvo un coeficiente kappa de 0,543 (p < 0,05), compatible con una concordancia moderada al considerar solo los pacientes remitidos desde atencion primaria con un diagnostico concreto. Conclusiones. Las cefaleas constituyen un motivo de consulta desde atencion primaria muy frecuente (15%). La concordancia diagnostica es moderada en nuestro sector sanitario, por lo que es necesario diseñar programas de formacion que ayuden a perfilar los criterios de derivacion al especialista y mejorar la atencion a nuestros pacientes.

Evaluating clinical dermatology practice in medical undergraduates.

The acquisition of competences (the set of knowledge, skills and attitudes required to perform a job to a professional level) is considered a fundamental part of medical training. Dermatology competences should include, in addition to effective clinical interviewing and detailed descriptions of skin lesions, appropriate management (diagnosis, differentiation, and treatment) of common skin disorders and tumors. Such competences can only be acquired during hospital clerkships. As a way of certifying these competences, we propose evaluating the different components as follows: knowledge, via clinical examinations or critical incident discussions; communication and certain instrumental skills, via structured workplace observation and scoring using a set of indicators; and attitudes, via joint evaluation by staff familiar with the student.

Influence of land use and climate on the load of suspended solids in catchments of Andean rivers.

Understanding the interaction between anthropogenic land use and the rainfall pattern can be crucial to predict changes in total suspended solids (TSS) in streams and rivers. We assessed the effects of land use and annual rainfall on the TSS load of 19 southern Chilean catchments. The results indicated that the concentration of TSS increased in catchments with a rainy regime and greater annual precipitation. TSS load also increased as the surface of open areas increased at the catchment scale and decreased with increasing cover of glaciers and perennial snow. However, we did not find support for models with interaction terms between climate and land use. Results suggest that a regional decrease in annual rainfall accompanied by an increase in the altitude of the zero isotherms, as predicted by climate models, should have multiple effects on TSS. In particular, increased TSS load can be expected from a contraction of glaciers and perennial snow areas as well as the intensification of new crops and urban expansion.

[Towards a comprehensive integration of obesity from an interdisciplinar perspective]. / Hacia una integración comprensiva de la obesidad desde una perspectiva multidisciplinar.

This article summarizes the current situation of one of the most important XXI century epidemics. The high rates of obesity in all countries and specially in our country at early ages are worrying. Traditionally, investigations have focused on the most nutritional aspects, such us dietary factors, metabolism, calory intake and energy expenditure. However, other sciences -such as Psychology- point out new influencing factors, such as food addiction, depression, stress and anxiety. In this piece of work, more than 80 articles from all disciplines and different databases and related to obesity are analyzed, as well as a new theoretical approach is proposed to ensure a more accurate comprehension. The literature review shows the necessary evidence to introduce a new model of obesity named edorexia, and raise issues to be resolved in future research oriented from a multidisciplinary perspective.

Evolution of butyric acid and the methanogenic microbial population in a thermophilic dry anaerobic reactor.

Knowledge of the relationship between the evolution of butyric acid, the main precursor of methane, and the methanogenic microbial population, quantified by fluorescent in situ hybridization (FISH), is important for understating and controlling the anaerobic digestion of solid waste. In this study, a statistical analysis has been made of this relationship in a laboratory-scale continuously stirred tank reactor (CSTR) without recycling of biomass. The CSTR has been operated at four organic loading rates (OLR) between 4.42 and 7.50 kg VS m(-3)day(-1), using the Organic Fraction of Municipal Solid Waste (OFMSW) as the substrate. During the start-up stage, the consumption of butyric acid is related to the population of H(2)-utilising methanogens (R(2)=0.774), whereas in the stabilization stage, it is related to that of acetoclastic methanogens (R(2)=0.716). Therefore, it can be concluded that the methanogenic population dynamics are closely correlated with the concentration of volatile fatty acids, and in particular, with that of butyric acid.

Spatial distribution of contaminants in sediments of two rivers crossing Tangier (northern Morocco).

The distribution and accumulation of heavy metals in the sediments of two rivers which cross various agglomerations of Tangier city, Morocco, were investigated. Surficial sediment samples were collected during 2005 and characterized for metal content (Zn, Pb, Cd, Cu, Cr and Ni), organic matter, total nitrogen, and n-hexane extractable material (HEM). The organic components (organic carbon, total nitrogen and HEM) show a slightly increasing enrichment from the upstream to the downstream of the emissary. An evaluation of the heavy metal pollution status of both tributaries was carried out using the metal pollution index (MPI). The results revealed the importance of anthropic pressure and the zones influenced by industrial discharges, which keep the metals Pb, Cr and Ni at high levels. Comparison with international regulatory guidelines for sediments revealed serious contamination of Cr, Zn and Ni.

An assessment of heavy metal contamination in surface sediment using statistical analysis.

The distribution and accumulation of heavy metals in the sediments, especially those nearest of wastewater discharges of south of Spain, were investigated. Sediment samples from 14 locations were collected and characterised for metal content (e.g. Ni, Cu, Zn, Cr, Pb, Mn, Cd and Hg), organic carbon, total nitrogen, total phosphorous, n-hexane-extractable material, carbonates and grain size. Concentration data were processed using correlation analysis and factor analysis. The correlation analysis of concentrations data showed important positive correlations among organic carbon, total phosphorus, Cu, Zn, Cd and Hg, otherwise weak correlations among Mn, Cr, Ni and CO(3) (2-), indicating that these metals have complicated geochemical behaviours. The use of statistical factor analysis also confirmed these results. Sediments pollution assessment was carried out using geoaccumulation and metal pollution indexes (MPI(8)). The results revealed that sediments of Cádiz bay and Sancti Petri channel were uncontaminated with the studied metals.

Analysis of methanogenic activity in a thermophilic-dry anaerobic reactor: use of fluorescent in situ hybridization.

Methanogenic activity in a thermophilic-dry anaerobic reactor was determined by comparing the amount of methane generated for each of the organic loading rates with the size of the total and specific methanogenic population, as determined by fluorescent in situ hybridization. A high correlation was evident between the total methanogenic activity and retention time [-0.6988Ln(x)+2.667] (R(2) 0.8866). The total methanogenic activity increased from 0.04x10(-8) mLCH(4) cell(-1)day(-1) to 0.38x10(-8) mLCH(4) cell(-1)day(-1) while the retention time decreased, augmenting the organic loading rates. The specific methanogenic activities of H(2)-utilizing methanogens and acetate-utilizing methanogens increased until they stabilised at 0.64x10(-8) mLCH(4) cell(-1)day(-1) and 0.33x10(-8) mLCH(4) cell(-1)day(-1), respectively. The methanogenic activity of H(2)-utilizing methanogens was higher than acetate-utilizing methanogens, indicating that maintaining a low partial pressure of hydrogen does not inhibit the acetoclastic methanogenesis or the anaerobic process.

Evaluation of metal contamination in sediments from north of Morocco: geochemical and statistical approaches.

Concentrations of Fe, Mn, Cr, Cu, Ni, Pb, Zn, Cd and Hg were evaluated in surface sediments of two rivers from north of Morocco, known as Souani and Mghogha rivers. Significantly higher concentrations in mg kg(-1) dry weight (dw) of Mn (747.6 vs. 392.9), Cr (86.4 vs. 56.3), Zn (299.5 vs. 138.5) were found in sediment samples from Mghogha when compared with Souani river. Average concentrations of Cd and Hg in several sediment samples from both rivers were above the effect range median that predicts toxic effects to aquatic organisms. The calculation of enrichment factors showed that Mn, Cr, Cu and Ni were depleted, whereas Pb and Hg were enriched. The results of geoaccumulation index revealed that sediments of both rivers were unpolluted with most of the metals and moderately contaminated with Fe and Hg. Some of elevated concentrations of Hg, principally in Mghogha River, were due to anthropogenic sources including the direct discharges of industrial zone.

Evolution of microorganisms in thermophilic-dry anaerobic digestion.

Microbial population dynamics were studied during the start-up and stabilization periods in thermophilic-dry anaerobic digestion at lab-scale. The experimental protocol was defined to quantify Eubacteria and Archaea using Fluorescent in situ hybridization (FISH) in a continuously stirred tank reactor (CSTR), without recycling solids. The reactor was subjected to a programme of steady-state operation over a range of the retention times from 40 to 25 days, with an organic loading rate between 4.42 and 7.50 kg volatile solid/m3/day. Changes in microbial concentrations were linked to traditional performance parameters such as biogas production and VS removal. The relations of Eubacteria:Archaea and H2-utilising methanogens:acetate-utilising methanogens were 88:12 and 11:1, respectively, during start-up stage. Hydrogenotrophic methanogens, although important in the initial phase of the reactor start-up, were displaced by acetoclastic methanogens at steady-state, thus their relation were 7:32, respectively. The methane yield coefficient, the methane content in the biogas and VS removal were stabilized around 0.30 LCH4/gCOD, 50% and 80%, respectively. Methanogenic population correlated well with performance measurements.

Intento autolítico por ingestión de cáusticos / Caustic ingestion in a suicide attempt

Las lesiones por ingestión de cáusticos suelen ser leves debido a que la toma del producto es escasa. Sin embargo, los intentos autolíticos conllevan graves daños esofágicos con más frecuencia. Pesentamos el caso clínico de un paciente de 14 años, con antecedentes depresivos, que acude a urgencias tras haber ingerido un producto decapante de pinturas, el cual resultó ser un potente álcali( pH>12)

The lesions produced by caustic substances are usually mild because the amount ingested is small. However, in a suicide attempt, serious damage to the esophagus is more common. We report the case of a 14-year-old patient with a previous diagnosis of depression, who was brought to the emergency service after drinking a caustic alkali

Thermal analysis in the evaluation of sediment pollution.

Characterization of organic matter in four sediments in the infuence area of wastewater discharges was carried out by both chemical and thermal analysis in order to assess their pollution level. Oxidisable organic carbon and organic matter were calculated by the standard methodology in laboratory. Thermogravimetry (TG), between 50 and 900 degrees C, was simultaneously performed in oxidizing conditions on ground sediments samples after three different pretreatments. Linear regression adjust of thermal analysis results versus chemical parameters provides the better Pearson's coefficients, leading to the best coefficients for weight loss in 250-400 degree C temperature range versus oxidisable organic carbon and organic matter at 360 degrees C, respectively. These results demonstrated the utility of thermoanalysis technique for the evaluation of the organic matter content of fresh sediments.

Structural and ultrastructural study of the intracranial portion of the oculomotor, trochlear and abducent nerves in dog.

The right intracranial portion of the oculomotor, trochlear and abducent nerves were removed from six adult German shepherd dogs and analysed by light and electron microscopy. In all cases the nerve sectional area was calculated. Unmyelinated and myelinated fibres were analysed and number, diameter and cross-sectional area were calculated. In myelinated fibres, also calculated were the corresponding axon area and diameter, and myelin sheath thickness. The mean number of myelinated fibres was 8543.50 +/- 1231.85 being the unmyelinated 1402 +/- 241.58 in the oculomotor nerve; 1509 +/- 223.17 and 287.67 +/- 72.28 in the trochlear nerve and 2473.00 +/- 211.41 and 231.25 +/- 92.67 respectively in the abducent. The mean diameter was 10.23 +/- 0.68 microm in myelinated and 0.43 +/- 0.21 for unmyelinated in oculomotor nerve, 10.53 +/- 0.55 microm and 0.33 +/- 0.04 for the trochlear, and 10.45 +/- 1.27 microm and 0.47 +/- 0.09 in the abducent nerve respectively. This study reveals that oculomotor, trochlear and abducent nerves of the dog show structural and ultra-structural features similar to the same nerves in other species.

Seudotumor testicular y síndrome constitucional / Testicular pseudotumor and constitutional syndrome

No disponible

[Spontaneous tumor lysis syndrome in a patient with non-Hodgkin's lymphoma]. / Síndrome de lisis tumoral espontáneo en una paciente con linfoma no Hodgkin.

An 77-year-old woman with no previous history of malignancy was admitted to the hospital with generalized weakness and malaise. Physical examination demonstrate multiple cervical adenopathies. The day after admission the patient developed severe metabolic derangements (hyperuricemia, hypocalcemia, hyperkalemia, hyperphosphatemia and azotemia) and expired. Consent for necropsy was refused. The cytology and molecular studies of cervical adenopathy sample were diagnostic of high-grade non-Hodgkin's lymphoma. A presumptive diagnosis of non Hodgkin lymphoma with spontaneous tumor lysis syndrome was made.

Síndrome de lisis tumoral espontáneo en una paciente con linfoma no Hodgkin / Spontaneous tumor lysis syndrome in a patient with non-Hodgkin´s lymphoma

Presentamos el caso de una mujer de 77 años sin antecedentes de proceso neoplásico que ingresa por la aparición en pocas semanas de múltiples adenopatías cervicales y que fallece a las pocas horas presentado hiperuricemia, hipocalcemia, hiperpotasemia, hiperfosfatemia e hiperazotemia. La citología y estudio molecular de una muestra de una adenopatía cervical fueron compatibles con de linfoma no Hodgkin de estirpe B de alto grado. Se trataría por tanto de un síndrome de lisis tumoral espontáneo como debut de un linfoma no Hodgkin

An 77-year-old woman with no previous history of malignancy was admited to the hospital with generalized weakness and malaise. Physical examination demostrate multiple cervical adenopathies. The day after admission the patient developed severe metabolic derangements (hyperuricemia, hypocalcemia, hyperkalemia, hyperphosphotemia and azotemia) and expired. Consent for necropsy was refused. The cytology and molecular studies of cervical adenopathy sample were diagnostic of high-grade non-Hodgkin’s lymphoma. A presumptive diagnosis of non Hodgkin lymphoma with spontaneous tumor lysis syndrome was made