Prediction of the bulking phenomenon in wastewater treatment plants

The control and prediction of wastewater treatment plants poses an important goal: to avoid breaking the environmental balance by always keeping the system in stable operating conditions. It is known that qualitative information — coming from microscopic examinations and subjective remarks — has a deep influence on the activated sludge process. In particular, on the total amount of effluent suspended solids, one of the measures of overall plant performance. The search for an input–output model of this variable and the prediction of sudden increases (bulking episodes) is thus a central concern to ensure the fulfillment of current discharge limitations. Unfortunately, the strong interrelationbetween variables, their heterogeneity and the very high amount of missing information makes the use of traditional techniques difficult, or even impossible. Through the combined use of several methods — rough set theory and artificial neural networks, mainly — reasonable prediction models are found, which also serve to show the different importance of variables and provide insight into the process dynamics

A study of the labour market trajectories in the Grand Duchy of Luxembourg

We present an analysis of the register of all unemployment episodes in the Grand Duchy of Luxembourg over a recent period of 55 months. We apply propensity score matching to account forthe systematic differences among the groups of subjects (registrants) and unemployment spells.We devise graphical and tabular summaries for describing the sequences of employment states ofthe members of the labour force who register at Agence pour le d?veloppement de l'emploi, theLuxembourg Public Unemployment Agency. Some employment-related information about themis collected by linking their records to the national register of social security contributions, maintained by Inspection g?n?rale de la s?curit? sociale. A class of univariate indices for characterisingthe sequences of labour force states is defined.

Preliminary results of the Social Impact Research Group of MEDEX: the request database (2000-2002) of two Meteorological Services

One of the aims of the MEDEX project is to improve the knowledge of high-impact weather events in the Mediterranean. According to the guidelines of this project, a pilot study was carried out in two regions of Spain (the Balearic Islands and Catalonia) by the Social Impact Research group of MEDEX. The main goal is to suggest some general and suitable criteria about how to analyse requests received in Meteorological Services arising out of the damage caused by weather events. Thus, all the requests received between 2000 and 2002 at the Servei Meteorològic de Catalunya as well as at the Division of AEMET in the Balearic Islands were analysed. Firstly, the proposed criteria in order to build the database are defined and discussed. Secondly, the temporal distribution of the requests for damage claims is analysed. On average, almost half of them were received during the first month after the event happened. During the first six months, the percentage increases by 90%. Thirdly, various factors are taken into account to determine the impact of specific events on society. It is remarkable that the greatest number of requests is for those episodes with simultaneous heavy rain and strong wind, and finally, those that are linked to high population density.

Predictive ability of severe rainfall events over Catalonia for the year 2008

This paper analyses the predictive ability of quantitative precipitation forecasts (QPF) and the so-called "poor-man" rainfall probabilistic forecasts (RPF). With this aim, the full set of warnings issued by the Meteorological Service of Catalonia (SMC) for potentially-dangerous events due to severe precipitation has been analysed for the year 2008. For each of the 37 warnings, the QPFs obtained from the limited-area model MM5 have been verified against hourly precipitation data provided by the rain gauge network covering Catalonia (NE of Spain), managed by SMC. For a group of five selected case studies, a QPF comparison has been undertaken between the MM5 and COSMO-I7 limited-area models. Although MM5's predictive ability has been examined for these five cases by making use of satellite data, this paper only shows in detail the heavy precipitation event on the 9¿10 May 2008. Finally, the "poor-man" rainfall probabilistic forecasts (RPF) issued by SMC at regional scale have also been tested against hourly precipitation observations. Verification results show that for long events (>24 h) MM5 tends to overestimate total precipitation, whereas for short events (¿24 h) the model tends instead to underestimate precipitation. The analysis of the five case studies concludes that most of MM5's QPF errors are mainly triggered by very poor representation of some of its cloud microphysical species, particularly the cloud liquid water and, to a lesser degree, the water vapor. The models' performance comparison demonstrates that MM5 and COSMO-I7 are on the same level of QPF skill, at least for the intense-rainfall events dealt with in the five case studies, whilst the warnings based on RPF issued by SMC have proven fairly correct when tested against hourly observed precipitation for 6-h intervals and at a small region scale. Throughout this study, we have only dealt with (SMC-issued) warning episodes in order to analyse deterministic (MM5 and COSMO-I7) and probabilistic (SMC) rainfall forecasts; therefore we have not taken into account those episodes that might (or might not) have been missed by the official SMC warnings. Therefore, whenever we talk about "misses", it is always in relation to the deterministic LAMs' QPFs.

Improving QPF by blending techniques at the Meteorological Service of Catalonia

The current operational very short-term and short-term quantitative precipitation forecast (QPF) at the Meteorological Service of Catalonia (SMC) is made by three different methodologies: Advection of the radar reflectivity field (ADV), Identification, tracking and forecasting of convective structures (CST) and numerical weather prediction (NWP) models using observational data assimilation (radar, satellite, etc.). These precipitation forecasts have different characteristics, lead time and spatial resolutions. The objective of this study is to combine these methods in order to obtain a single and optimized QPF at each lead time. This combination (blending) of the radar forecast (ADV and CST) and precipitation forecast from NWP model is carried out by means of different methodologies according to the prediction horizon. Firstly, in order to take advantage of the rainfall location and intensity from radar observations, a phase correction technique is applied to the NWP output to derive an additional corrected forecast (MCO). To select the best precipitation estimation in the first and second hour (t+1 h and t+2 h), the information from radar advection (ADV) and the corrected outputs from the model (MCO) are mixed by using different weights, which vary dynamically, according to indexes that quantify the quality of these predictions. This procedure has the ability to integrate the skill of rainfall location and patterns that are given by the advection of radar reflectivity field with the capacity of generating new precipitation areas from the NWP models. From the third hour (t+3 h), as radar-based forecasting has generally low skills, only the quantitative precipitation forecast from model is used. This blending of different sources of prediction is verified for different types of episodes (convective, moderately convective and stratiform) to obtain a robust methodology for implementing it in an operational and dynamic way.

Unusual concentration of Early Albian arthropod-bearing amber in the Basque-Cantabrian Basin (El Soplao, Cantabria, Spain): Palaeoenvironmental and paleobiological implications.

The El Soplao site is a recently-discovered Early Albian locality of the Basque-Cantabrian Basin (northern Spain) that has yielded a number of amber pieces with abundant bioinclusions. The amber-bearing deposit occurs in a non-marine to transitional marine siliciclastic unit (Las Peñosas Formation) that is interleaved within a regressive-transgressive, carbonate-dominated Lower Aptian-Upper Albian marine sequence. The Las Peñosas Formation corresponds to the regressive stage of this sequence and in its turn it splits into two smaller regressive-transgressive cycles. The coal and amber-bearing deposits occur in deltaic-estuarine environments developed during the maximum regressive episodes of these smaller regressive-transgressive cycles. The El Soplao amber shows Fourier Transform Infrared Spectroscopy spectra similar to other Spanish Cretaceous ambers and it is characterized by the profusion of sub-aerial, stalactite-like flows. Well-preserved plant cuticles assigned to the conifer genera Frenelopsis and Mirovia are abundant in the beds associated with amber. Leaves of the ginkgoalean genera Nehvizdya and Pseudotorellia also occur occasionally. Bioinclusions mainly consist of fossil insects of the orders Blattaria, Hemiptera, Thysanoptera, Raphidioptera, Neuroptera, Coleoptera, Hymenoptera and Diptera, although some spiders and spider webs have been observed as well. Some insects belong to groups scarce in the fossil record, such as a new morphotype of the wasp Archaeromma (of the family Mymarommatidae) and the biting midge Lebanoculicoides (of the monogeneric subfamily Lebanoculicoidinae). This new amber locality constitutes a very significant finding that will contribute to improving the knowledge and comprehension of the Albian non-marine paleoarthropod fauna.

Upper gastrointestinal bleeding in cirrhosis: clinical and endoscopic correlations

The clinical data of 180 episodes of upper gastrointestinal bleeding in 168 patients with cirrhosis of the liver are examined. The source of bleeding had been determined by early endoscopy in all cases. In men under the age of 50 years, and without symptoms of liver failure, bleeding was due to ruptured gastro-oesophageal varices in 84% of cases. Severe liver failure was associated with acute lesions of gastric mucosa in many cases. No presumptive diagnosis of the source of haemorrhage could be based on the examination of other clinical data (presence of ascites, mode of presentation and pattern of bleeding, history of ulcer disease, alcoholism, and previous medication.

Upper gastrointestinal bleeding in cirrhosis: clinical and endoscopic correlations

The clinical data of 180 episodes of upper gastrointestinal bleeding in 168 patients with cirrhosis of the liver are examined. The source of bleeding had been determined by early endoscopy in all cases. In men under the age of 50 years, and without symptoms of liver failure, bleeding was due to ruptured gastro-oesophageal varices in 84% of cases. Severe liver failure was associated with acute lesions of gastric mucosa in many cases. No presumptive diagnosis of the source of haemorrhage could be based on the examination of other clinical data (presence of ascites, mode of presentation and pattern of bleeding, history of ulcer disease, alcoholism, and previous medication.

Reconstructing snow avalanches in the Southeastern Pyrenees

A regional study of snow avalanche processes was undertaken in the SE Pyrenees. Dendrogeomorphology was used to date and reconstruct large-scale snow avalanche events that occurred in the last four decades. Dendrochronological analyses yielded the dates of nine winters when avalanches occurred in the recent past in six studied avalanche paths. Some of these avalanches were already known, but others had not been documented. In one case, the existing avalanche path map was improved with the dendrogeomorphological information of a larger past event. As a result of the dendrogeomorphological analyses, evidence for three regional-scale major avalanche years was identified in the SE Pyrenees from 1971 to 2004: 1971¿1972, 1995¿1996 and 2002¿2003. The specific synoptic atmospheric situations and the most likely nivometeorological and snowpack conditions that released these major avalanches were determined using weather data for the seasons of major avalanche releases. In 1971¿1972 the snow avalanche episode was characterized by a deep trough crossing the Pyrenees. In 1995¿1996 a variety of meteorological situations produced several episodes of major avalanches. In 2002¿2003 the more significant of two episodes was attributed to a north advection pumping an arctic air mass over the Pyrenees. The 1995¿1996 avalanche season proved to be the most notable in the four past decades in the Pyrenees.

Buenos libros, malas lectoras: la enfermedad moral de las mujeres del siglo XIX

El seu article parteix de l'afirmació que el destí de les dones al segle XIX està marcat, en la ficció, pel "bovarysme", malaltia que proposa que les dones s'emmalalteixen i moren perquè llegeixen malament. El treball analitza aquest problema de la "mala lectura" traçant un recorregut que va des de Fernán Caballero fins a Freud i es comenten alguns episodis de lectura que apareixen en la "Autobiografía" de Gertrudis Gómez de Avellaneda, Clemencia, Amalia, Madame Bovary, María, La regenta i El caso Dora. Her article departs from the statement that the destiny of women in the 19th century is determined, in fiction, by "bovarysm", an illness which proposes that women get sick and die because they read incorrectly. The work analyzes this problem of "bad reading" tracing a journey from Fernán Caballero to Freud, and comments on several episodes about the act of reading, from Gertrudis Gómez de Avellaneda's "Autobiography", Clemencia, Amalia, Madame Bovary, María, La Regenta and Dora's Case.

Depositional models of lacustrine evaporites in the SE margin of the Ebro basin (Paleogene, NE Spain)

An important evaporitic sedimentation occurred during the Paleogene (Eocene to lower Oligocene) in the Barberà sector of the southeastern margin of the Tertiary Ebro Basin. This sedimentation took place in shallow lacustrine environments and was controlled by a number of factors: 1) the tectonic structuration of the margin; 2) the high calcium sulphate content in the meteoric waters coming from the marginal reliefs; 3) the semiarid climate; and 4) the development of large alluvial fans along the basin margin, which also conditioned the location of the saline lakes. The evaporites are currently composed of secondary gypsum in surface and anhydrite at depth. There are, however, vestiges of the local presence of sodium sulphates. The evaporite units, with individual thicknesses ranging between 50 and 100 m, are intercalated within various lithostratigraphic formations and exhibit a paleogeographical pattern. The units located closer to the basin margin are characterized by a massive gypsum lithofacies (originally, bioturbated gypsum) bearing chert, and also by meganodular gypsum locally (originally, meganodules of anhydrite) in association with red lutites and clastic intercalations (gypsarenites, sandstones and conglomerates). Chert, which is only linked to the thickest gypsum layers, seems to be an early diagenetic, lacustrine product. Cyclicity in these proximal units indicates the progressive development of lowsalinity, lacustrine bodies on red mud flats. At the top of some cycles, exposure episodes commonly resulted in dissolution, erosion, and the formation of edaphic features. In contrast, the units located in a more distal position with regard to the basin margin are formed by an alternation of banded-nodular gypsum and laminated gypsum layers in association with grey lutites and few clastic intercalations. These distal units formed in saline lakes with a higher ionic concentration. Exposure episodes in these lakes resulted in the formation of synsedimentary anhydrite and sabkha cycles. In some of these units, however, outer rims characterized by a lithofacies association similar to that of the proximal units occur (nodular gypsum, massive gypsum and chert nodules).

Buenos libros, malas lectoras: la enfermedad moral de las mujeres del siglo XIX

El seu article parteix de l'afirmació que el destí de les dones al segle XIX està marcat, en la ficció, pel "bovarysme", malaltia que proposa que les dones s'emmalalteixen i moren perquè llegeixen malament. El treball analitza aquest problema de la "mala lectura" traçant un recorregut que va des de Fernán Caballero fins a Freud i es comenten alguns episodis de lectura que apareixen en la "Autobiografía" de Gertrudis Gómez de Avellaneda, Clemencia, Amalia, Madame Bovary, María, La regenta i El caso Dora. Her article departs from the statement that the destiny of women in the 19th century is determined, in fiction, by "bovarysm", an illness which proposes that women get sick and die because they read incorrectly. The work analyzes this problem of "bad reading" tracing a journey from Fernán Caballero to Freud, and comments on several episodes about the act of reading, from Gertrudis Gómez de Avellaneda's "Autobiography", Clemencia, Amalia, Madame Bovary, María, La Regenta and Dora's Case.

Incidencia de la incapacidad temporal por contingencia común y profesional en la muestra continua de vidas laborales en 2009

Objetivo: Describir la incidencia de la incapacidad temporal por contingencia común (ITcc) y profesional (ITcp) iniciada en 2009 en afiliados a la Seguridad Social (SS) que forman parte de la Muestra Continua de Vida Laboral.Métodos: Cohorte formada por 873.008 afiliados a la SS en España que registraron 163.008 episodios de IT con un tiempo acumulado total en riesgo de 675.923,6 trabajadores-año. Se estimó la tasa de incidencia de todos los primeros episodios de IT y por trastornos musculo-esqueléticos (TME) según variables demográficas y laborales. Posteriormente se calcularon las razones de tasas crudas (RTc) y ajustadas (RTa) mediante un modelo de regresión Poisson.Resultados: La incidencia de la ITcc e ITcp fue de 23,1 y 1,0 casos por 100 trabajadores-año, respectivamente. La incidencia por ITcc fue superior en mujeres, en menores de 26 años y en Navarra (32,8 casos por 100 trabajadores-año), y por ITcp las mayores incidencias se observaron en hombres y en Galicia. Por diagnóstico, los TME presentaron 424,7 casos y 3,6 casos por 10.000 trabajadores-año según contingencia común y profesional respectivamente. Por otra parte, los trabajadores temporales tuvieron más riesgo de desarrollar ITcp (RTa=1,09;IC95%=1,04-1,15) e ITcc (RTa=1,02;IC95%=1,01-1,03) respecto a los permanentes.Conclusiones: La incidencia de la IT sigue un mismo patrón según edad, régimen de afiliación y relación laboral. Por tipo de contingencia se observaron diferencias en la ocupación, sexo, tamaño de empresa, comunidad autónoma y actividad económica. Es necesario estudiar con más detenimiento las diferencias observadas por actividad económica y tipo de relación contractual.

Heterogeneity and event dependence in the analysis of sickness absence

Sickness absence (SA) is an important social, economic and public health issue. Identifying and understanding the determinants, whether biological, regulatory or, health services-related, of variability in SA duration is essential for better management of SA. The conditional frailty model (CFM) is useful when repeated SA events occur within the same individual, as it allows simultaneous analysis of event dependence and heterogeneity due to unknown, unmeasured, or unmeasurable factors. However, its use may encounter computational limitations when applied to very large data sets, as may frequently occur in the analysis of SA duration. To overcome the computational issue, we propose a Poisson-based conditional frailty model (CFPM) for repeated SA events that accounts for both event dependence and heterogeneity. To demonstrate the usefulness of the model proposed in the SA duration context, we used data from all non-work-related SA episodes that occurred in Catalonia (Spain) in 2007, initiated by either a diagnosis of neoplasm or mental and behavioral disorders. As expected, the CFPM results were very similar to those of the CFM for both diagnosis groups. The CPU time for the CFPM was substantially shorter than the CFM. The CFPM is an suitable alternative to the CFM in survival analysis with recurrent events,especially with large databases.

La depressió major i els esdeveniments estressants vitals

Introducció: La Depressió Major (DM) és una malaltia psiquiàtrica freqüent en la societat actual. Cada vegada més, es relaciona la DM amb els esdeveniments estressants vitals (EEV) i un d’aquests EEV és l’actual situació de crisis econòmica que afegeix un risc degut a la desigualtat que representa per la persona en termes econòmics.Metodologia: S’ha dut a terme una revisió de la literatura a les bases de dades Pubmed, ElSevier i PsycInfo en els últims 15 anys utilitzant les paraules clau “major depressive disorder”, “depression”, “stressful events” i “life events”.Resultats: Es troben 11 articles que relacionen la depressió major amb els esdeveniments estressants vitals. Tots els articles revisats coincideixen en que els EEV tenen una relació amb la DM i a partir d’aquí s’estableixen altres variables com els EEV dependents i independents, la influència del gènere, l’edat, del factor genètic i la de la història depressiva prèvia.Conclusions: L’exposició als EEV augmenta el risc de desenvolupar una DM. Altres variables com el factor genètic i l’edat també es relacionen amb els EEV. Hi ha certa evidència que aquells entre 41 i 57 anys tenen major incidència d’EEV com a causant d’una DM. També s’ha descrit una relació directe entre el risc genètic i la incidència d’EEV. Ara bé, quants més episodis depressius previs menys probabilitats de patir una DM degut als EEV