998 resultados para 289.272


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Occupational hygiene practitioners typically assess the risk posed by occupational exposure by comparing exposure measurements to regulatory occupational exposure limits (OELs). In most jurisdictions, OELs are only available for exposure by the inhalation pathway. Skin notations are used to indicate substances for which dermal exposure may lead to health effects. However, these notations are either present or absent and provide no indication of acceptable levels of exposure. Furthermore, the methodology and framework for assigning skin notation differ widely across jurisdictions resulting in inconsistencies in the substances that carry notations. The UPERCUT tool was developed in response to these limitations. It helps occupational health stakeholders to assess the hazard associated with dermal exposure to chemicals. UPERCUT integrates dermal quantitative structure-activity relationships (QSARs) and toxicological data to provide users with a skin hazard index called the dermal hazard ratio (DHR) for the substance and scenario of interest. The DHR is the ratio between the estimated 'received' dose and the 'acceptable' dose. The 'received' dose is estimated using physico-chemical data and information on the exposure scenario provided by the user (body parts exposure and exposure duration), and the 'acceptable' dose is estimated using inhalation OELs and toxicological data. The uncertainty surrounding the DHR is estimated with Monte Carlo simulation. Additional information on the selected substances includes intrinsic skin permeation potential of the substance and the existence of skin notations. UPERCUT is the only available tool that estimates the absorbed dose and compares this to an acceptable dose. In the absence of dermal OELs it provides a systematic and simple approach for screening dermal exposure scenarios for 1686 substances.

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The objective of this study is to assess the results of labyrinthine fenestration for fixed stapes in chronic ear disease. Using a prospective database, pre- and postoperative audiometric data from patients undergoing labyrinthine fenestration for fixation of the stapes in chronic ear disease others than otosclerosis between 2002 and 2012 were evaluated. Twenty-three labyrinthine fenestrations in chronic ear disease were performed (17 malleo-stapedotomies, 4 incus-stapedotomies, 1 neo-malleus-stapedotomy, 1 TORP-stapedotomy). Overall, the mean short-term (2 months) and long-term (42 months) postoperative air-bone gap (0.5-3 kHz) were 17.5 and 16.5 dB, respectively; long-term air-bone gap of <20 dB was obtained in 73 % of patients. There was no significant difference in air-bone gap closure between tympanosclerotic and post inflammatory osteogenic fixation of the stapes (p = 0.267). Hearing benefit success using the 'Belfast rule of the thumb' was achieved in 48 %. Normal bilateral hearing was achieved in 17 % and bilateral symmetric hearing impairment in 26 %. Only in 4 %, bone conduction worsened by more than 5 dB. Labyrinthine fenestration is an option in selected cases of stapes fixation in chronic ear disease and provides hearing gain without significant risk for sensorineural hearing loss. In those already selected cases, hearing benefit success 'Belfast rule of the thumb' is achieved only in half of the cases. This and the possible alternatives, should therefore be discussed preoperatively.

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The combination of high performance exclusion chromatography (HPEC) and gas chromatography (GC) was applied to the analysis of six coffee samples that were previously characterized by sensory tests as of good or poor quality. The data obtained by the two techniques were statistically evaluated by "Principal Components Analysis" (PCA) using selected peak areas. The results showed the potential of the described techniques for coffee analysis. The HPEC technique monitored with the U.V. detector at 272 nm and followed by PCA may be correlated with sensorial data, particularly if a wider group of samples is used.

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OBJECTIVES: Polypharmacy is one of the main management issues in public health policies because of its financial impact and the increasing number of people involved. The polymedicated population according to their demographic and therapeutic profile and the cost for the public healthcare system were characterised. DESIGN: Cross-sectional study. SETTING: Primary healthcare in Barcelona Health Region, Catalonia, Spain (5 105 551 inhabitants registered). PARTICIPANTS: All insured polymedicated patients. Polymedicated patients were those with a consumption of ≥16 drugs/month. MAIN OUTCOMES MEASURES: The study variables were related to age, gender and medication intake obtained from the 2008 census and records of prescriptions dispensed in pharmacies and charged to the public health system. RESULTS: There were 36 880 polymedicated patients (women: 64.2%; average age: 74.5±10.9 years). The total number of prescriptions billed in 2008 was 2 266 830 (2 272 920 total package units). The most polymedicated group (up to 40% of the total prescriptions) was patients between 75 and 84 years old. The average number of prescriptions billed monthly per patient was 32±2, with an average cost of 452.7±27.5. The total cost of those prescriptions corresponded to 2% of the drug expenditure in Catalonia. The groups N, C, A, R and M represented 71.4% of the total number of drug package units dispensed to polymedicated patients. Great variability was found between the medication profiles of men and women, and between age groups; greater discrepancies were found in paediatric patients (5-14 years) and the elderly (≥65 years). CONCLUSIONS: This study provides essential information to take steps towards rational drug use and a structured approach in the polymedicated population in primary healthcare.

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The amphiphilic nature of metal extractants causes the formation of micelles and other microscopic aggregates when in contact with water and an organic diluent. These phenomena and their effects on metal extraction were studied using carboxylic acid (Versatic 10) and organophosphorus acid (Cyanex 272) based extractants. Special emphasis was laid on the study of phase behaviour in a pre neutralisation stage when the extractant is transformed to a sodium or ammonium salt form. The pre neutralised extractants were used to extract nickel and to separate cobalt and nickel. Phase diagrams corresponding to the pre neutralisation stage in a metal extraction process were determined. The maximal solubilisation of the components in the system water(NH3)/extractant/isooctane takes place when the molar ratio between the ammonia salt form and the free form of the extractant is 0.5 for the carboxylic acid and 1 for the organophosphorus acid extractant. These values correspond to the complex stoichiometry of NH4A•HA and NIi4A, respectively. When such a solution is contacted with water a microemulsion is formed. If the aqueous phase contains also metal ions (e.g. Ni²+), complexation will take place on the microscopic interface of the micellar aggregates. Experimental evidence showing that the initial stage of nickel extraction with pre neutralised Versatic 10 is a fast pseudohomogeneous reaction was obtained. About 90% of the metal were extracted in the first 15 s after the initial contact. For nickel extraction with pre neutralised Versatic 10 it was found that the highest metal loading and the lowest residual ammonia and water contents in the organic phase are achieved when the feeds are balanced so that the stoichiometry is 2NH4+(org) = Nit2+(aq). In the case of Co/Ni separation using pre neutralised Cyanex 272 the highest separation is achieved when the Co/extractant molar ratio in the feeds is 1 : 4 and at the same time the optimal degree of neutralisation of the Cyanex 272 is about 50%. The adsorption of the extractants on solid surfaces may cause accumulation of solid fine particles at the interface between the aqueous and organic phases in metal extraction processes. Copper extraction processes are known to suffer of this problem. Experiments were carried out using model silica and mica particles. It was found that high copper loading, aromacity of the diluent, modification agents and the presence of aqueous phase decrease the adsorption of the hydroxyoxime on silica surfaces.

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Soitinnus: mieskuoro (TTBB).

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Un dels problemes típics de regulació en el camp de l’automatització industrial és el control de velocitat lineal d’entrada del fil a les bobines, ja que com més gruix acumulem a igual velocitat de rotació de la bobina s’augmenta notablement la velocitat lineal d’entrada del fil, aquest desajust s’ha de poder compensar de forma automàtica per aconseguir una velocitat d’entrada constant. Aquest problema de regulació de velocitats és molt freqüent i de difícil control a la indústria on intervé el bobinat d’algun tipus de material com cablejat, fil, paper, làmines de planxa, tubs, etc... Els dos reptes i objectius principals són, primer, la regulació de la velocitat de rotació de la bobina per aconseguir una velocitat lineal del fil d’entrada, i segon, mitjançant el guiatge de l’alimentació de fil a la bobina, aconseguir un repartiment uniforme de cada capa de fil. El desenvolupament consisteix amb l’automatització i control d’una bobinadora automàtica mitjançant la configuració i programació de PLC’s, servomotors i encoders. Finalment es farà el muntatge pràctic sobre una bancada per verificar i simular el seu correcte funcionament que ha de donar solució a aquests problemes de regulació de velocitats. Com a conclusions finals s’han aconseguit els objectius i una metodologia per fer una regulació de velocitats de rotació per bobines, amb accionaments de servomotors amb polsos, i a nivell de coneixements he aconseguit dominar les aplicacions d’aquest tipus d’accionaments aplicats a construccions mecàniques.

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JCM és una empresa dedicada al disseny de sistemes de control d’accés. Disposa d’uns equips elèctrics amb molts paràmetres configurables, així es poden utilitzar en molts tipus d’instal•lació. Aquets paràmetres són configurables pels clients. JCM, disposa d’un servei d’atenció telefònica (SAT), que intenta donar solucions a tots els problemes que puguin sorgir als clients. Sovint, no poden donar suport als dubtes dels clients per culpa de la poca informació que reben a través del client. L'objectiu del projecte és resoldre el problema de falta d'informació i mala comunicació per millorar la qualitat del servei que ofereix el SAT. La solució, no ha d’alterar el cost de producció del producte. S’ha de tenir en compte també que els equips poden estar instal•lats en qualsevol part del món i que només es poden utilitzar recursos de fàcil accés per tots els clients. Per complir amb aquests objectius, emetrem un missatge, a través del brunzidor del equip, amb la informació de configuració de l'equip. Aquest missatge viatjarà a través de la xarxa telefònica fins al SAT. Un cop allà, el descodificarem i n'enviarem les dades a un PC perquè pugui presentar les dades sobre la configuració de una forma clara pel SAT.

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The research assesses the skills of upper comprehensive school pupils in history. The focus is on locating personal motives, assessing wider reasons hidden in historical sources and evaluating source reliability. The research also questions how a wide use of multiple sources affects pupils’ holistic understanding of historical phenomena. The participants were a multicultural group of pupils. The origins of their cultures can be traced to the Balkan, the Middle East, Asia and Europe. The number of native Finnish speakers and pupils speaking Finnish as their second language was almost equal. The multicultural composition provides opportunities to assess how culturally responsive learning history from sources is. The intercultural approach to learning in a multicultural setting emphasizes equality as a precondition for learning. In order to set assignments at least to some extent match with all participants only those answers were taken into account which were produced by pupils who had studied history for a similar period of time in the Finnish comprehensive school system. Due to the small number of participants (41), the study avoids wide generalizations. Nevertheless, possible cultural blueprints in pupils’ way of thinking are noted. The first test examined the skills of pupils to find motives for emigration. The results showed that for 7th graders finding reasons is not a problematic task. However, the number of reasons noticed and justifications varied. In addition, the way the pupils explained their choices was a distinguishing factor. Some pupils interpreted source material making use of previous knowledge on the issue, while other pupils based their analysis solely on the text handed and did not try to add their own knowledge. Answers were divided into three categories: historical, explanatory and stating. Historical answers combined smoothly previously learned historical knowledge to one’s own source analysis; explanatory answers often ignored a wider frame, although they were effective when explaining e.g. historical concepts. The stating answers only noticed motives from the sources and made no attempts to explain them historically. Was the first test culturally responsive? All pupils representing different cultures tackled the first source exam successfully, but there were some signs of how historical concepts are understood in a slightly different way if the pupil’s personal history has no linkage to the concepts under scrutiny. The second test focused on the history of Native Americans. The test first required pupils to recognize whether short source extracts (5) were written by Indians or Caucasians. Based on what they had already learned from North American history, the pupils did not find it hard to distinguish between the sources. The analysis of multiphase causes and consequences of the disputes between Native Americans and white Americans caused dispersion among pupils. Using two historical sources and combining historical knowledge from both of them simultaneously was cumbersome for many. The explanations of consequences can be divided into two groups: the ones emphasizing short term consequences and those placing emphasis on long term consequences. The short term approach was mainly followed by boys in every group. The girls mainly paid attention to long term consequences. The result suggests that historical knowledge in sources is at least to some extent read through role and gender lenses. The third test required pupils to explain in their own words how the three sources given differed in their account of living conditions in Nazi Germany, which turned out to be demanding for many pupils. The pupils’ stronghold was rather the assessment of source reliability and accounts why the sources approached the same events differently. All participants wrote critical and justified comments on reliability and aspects that might have affected the content of the sources. The pupils felt that the main reasons that affected source reliability were the authors’ ethnic background, nationality and profession. The assessment showed that pupils were well aware that position in a historical situation has an impact on historical accounts, but in certain cases the victim’s account was seen as a historical truth. The account of events by a historian was chosen most often as the most reliable source, but it was often justified leniently with an indication to professionalism rather than with clear ideas of how historians conduct accounts based on sources. In brief, the last source test demonstrates that pupils have a strong idea that the ethnicity or nationalism determines how people explained events of the past. It is also an implication that pupils understand how historical knowledge is interpretative. The results also imply that history can be analyzed from a neutral perspective. One’s own membership in an ethnical or religious group does not automatically mean that a person’s cultural identity excludes historical explanations if something in them contradicts with his or her identity. The second method of extracting knowledge of pupils’ historical thinking was an essay analysis. The analysis shows that an analytical account of complicated political issues, which often include a great number of complicated political concepts, leads more likely to an inconsistent structure in the written work of pupils. The material also demonstrates that pupils have a strong tendency to take a critical stance when assessing history. Historical empathy in particular is shown if history somehow has a linkage to young people, children or minorities. Some topics can also awake strong feelings, especially among pupils with emigrant background, if there is a linkage between one’s own personal history and that of the school; and occasionally a student’s historical experience or thoughts replaced school history. Using sources during history lessons at school seems to have many advantages. It enhances the reasoning skills of pupils and their skills to assess the nature of historical knowledge. Thus one of the main aims and a great benefit of source work is to encourage pupils to express their own ideas and opinions. To conclude, when assessing the skills of adolescents in history - their work with sources, comments on history, historical knowledge and finally their historical thinking - one should be cautious and avoid cut off score evaluations. One purpose of pursuing history with sources is to encourage pupils to think independently, which is a useful tool for further identity construction. The idea that pupils have the right to conduct their own interpretations of history can be partially understood as part of a wider learning process, justification to study history comes from extrinsic reasons. The intrinsic reason is history itself; in order to understand history one should have a basic understanding of history as a specific domain of knowledge. Using sources does not mean that knowing history is of secondary importance. Only a balance between knowing the contextual history, understanding basic key concepts and working with sources is a solid base to improve pupils’ historical understanding.

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1816/10/15 (Numéro 289).

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1816/09/28 (Numéro 272).

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Invocatio: D.D.

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Invocatio: I.N.J.