Propelente sólido compósito polibutadiênico: I- influência do agente de ligação

In the Brazilian Complete Spacial Mission, the research of Vehicle Satellite Launcher is important. The solid propellant composite used in this vehicle is made with ammonium perchlorate, aluminiun powder and hydroxy terminated polibutadiene resin. In the propellant the bonding agent has a function to promote the interaction between solids and polimeric matrix, improving mechanical properties as stress, strain, aging characteristics and moisture embrittlement. Due its importance in propellant, bonding agent is consider as industrial secret and the literature about it is generic, without greater informations.

Avaliação das condições ambientais da lagoa de Varano, no sul da Itália

In the sediments of Varano lagoon (South Italy) were evaluated the concentration of some toxic heavy metals. Besides in the same sites were determinated the bioluminescent inhibition of eluate sediments by Toxalert® 10 and all matrix datas comparated with biological classification proposed by author Frisoni based on abundance level of macrozoobenthos. The results from three tipes of approches (ecotoxicological, chemical and biological ) show a similar trend.

Análisis psicométrico de la escala multidimensional de autoconcepto AF5 en una muestra de adolescentes y adultos de Cataluña

Psychometric analysis of the AF5 multidimensional scale of self-concept in a sample of adolescents and adults in Catalonia. The aim of this study is to carry out a psychometric study of the AF5 scale in a sample of 4.825 Catalan subjects from 11 to 63 years-old. They are students from secondary compulsory education (ESO), from high school, middle-level vocational training (CFGM) and from the university. Using a principal component analysis (PCA) the theoretical validity of the components is established and the reliability of the instrument is also analyzed. Differential analyses are performed by gender and normative group using a 2 6 factorial design. The normative group variable includes the different levels classifi ed into 6 sub-groups: university, post-compulsory secondary education (high school and CFGM), 4th of ESO, 3rd of ESO, 2nd of ESO and 1st of ESO. The results indicate that the reliability of the Catalan version of the scale is similar to the original scale. The factorial structure also fi ts with the original model established beforehand. Signifi cant differences by normative group in the four components of self-concept explored (social, family, academic/occupational and physical) are observed. By gender, signifi cant differences appear in the component of physical self-concept, academic and social but not in the family component

Extração sortiva em barra de agitação para análise de fármacos em fluidos biológicos

A novel solventless sample preparation, stir-bar sorptive extraction (SBSE), for extraction, and sample enrichment of organic compounds from biological fluids, is described in this manuscript from principle to applications. The SBSE is based on sorptive extraction, whereby the compounds are extracted into a polymer coating, polydimethylsiloxane (PDMS), on a magnetic stirring rod. The extraction is controlled by the partitioning coefficient of drugs between the PDMS and sample matrix, and upon the sample-extraction medium phase ratio. The SBSE technique has been applied successfully, with high sensitivities, to biomedical analysis of volatiles and for semi-volatiles drugs from biological sample, including urine, plasma, and saliva. SBSE combined with in situ derivatization, drugs quite more polar (e.g. metabolites) also can be analyzed.

Variables cognitivas y metacognitivas en la resolución de problemas de química: propuesta de estrategias didácticas

This paper presents and classifies the cognitive and metacognitive variables involved in the processes that students execute in problem solving. Moreover, it shows how these variables affect the students success in problem solving. These variables are classified in: piagetian and neo-piagetian, representational, metacognitive and transfer of learning. In the first group of variables it is discussed formal reasoning ability and other neo-piagetian factors. In the second group of variables it is analysed mental models and external representations. Implications for chemistry education are collected as a proposal of didactic strategies in the classroom.

Aplicação da cromatografia gasosa bidimensional abrangente com microdetector de captura de elétrons para determinação de agrotóxicos em sedimentos

Analysis of seven pesticides in sediments was successfully achieved using comprehensive two-dimensional gas chromatography with micro-electron capture detection, as it provided higher sensitivity and less matrix interference. Repeatability and intermediate precision of peak areas and heights were less than 4% and the recovery percentage for the analytes ranged from 52 to 115%. Instrumental LOD and LOQ were in the range of 0.60 to 2.31 μg L-1 and 1.83 to 5.62 μg L-1, respectively. Concentrations of 3.34 μg kg-1 (dry basis) for trifloxystrobin and azoxystrobin (below the LOQ) were found in a sediment sample.

Novas métricas holísticas para avaliação da verdura de reações de síntese em laboratório

New semi-quantitative metrics for simple evaluation of global greenness of chemical reactions used in teaching laboratories, namely, the Green Circle (GC) and Green Matrix (GM), were developed. These metrics globally consider all Twelve Principles of Green Chemistry. To illustrate their construction, the greenness of several syntheses performed in the laboratory under different sets of conditions was assessed. The tools were validated by comparing the results with another metric, the Green Star (GS), developed in our previous study. Results showed these new metrics were useful for the intended purpose, having the advantage of being simpler than the GS.

Revisão dos tratamentos químicos da fibra natural para mistura com poliolefinas

The use of natural fibers as reinforcement in polymer composites has been a focus of interest. However, these composites exhibit lower mechanical properties than those of pure polymers because of the low interfacial interactions between the hydrophobic polymer matrix and the hydrophilic fiber. To overcome this problem, different chemical treatments applied to the fibers have been reported. One of the most used treatments is mercerization, which can improve adhesion between the fiber and polymeric matrix. Another chemical treatment involves the use of acids (stearic and oleic acids). The chemically treated fibers used in composite materials showed improved mechanical properties.

Composição elementar do aerossol atmosférico na região central da Bacia Amazônica

The processes and sources that regulate the elemental composition of aerosol particles were investigated in both fine and coarse modes during the dry and wet seasons. One hundred and nine samples were collected from the biological reserve Cuieiras - Manaus from February to October 2008, and analyzed together with 668 samples that were previously collected at Balbina from 1998 to 2002. Particle induced X-ray emission technique was used to determine the elemental composition, while the concentration of black carbon was obtained from the measurement of optical reflectance. Absolute principal factor analysis and positive matrix factorization were performed for source apportionment, which was complemented with back trajectory analysis. A regional identity for the natural biogenic aerosol was found for the Central Amazon Basin and can be used in dynamical chemical region models.

Strategian jalkauttamista tukeva optimaalinen toimintaympäristö kilpailuedun lähteenä

Tutkimus käsittelee strategian jalkauttamista. Tutkimuksen tavoitteena on kuvata millainen on strategian jalkauttamista tukeva optimaalinen toimintaympäristö kilpailuedun lähteenä. Tavoitteeseen päästään neljän alaongelman avulla: mistä elementeistä toimintaympäristö koostuu, millaisia yhteyksiä elementeillä on toisiinsa, mitkä elementeistä liittyvät johtamiseen ja millainen rooli keskijohdolla on strategian jalkauttamisessa. Tapaustutkimus on luonteeltaan kvalitatiivinen ja tutkimusote normatiivinen. Tutkimuksen teoreettinen viitekehys kattaa kuusi kokonaisuutta: strategian ja strategisen johtamisen, ulkoisen ja sisäisen toimintaympäristön, kilpailuedun, kulttuurin sekä johtamisen ja operatiivisen toiminnan. Johtaminen ja operatiivinen toiminta koostuu seitsemästä elementistä: asiakkaat, yhteys, yhteisöllisyys, kontrolli, kommunikointi, ydinkyvykkyydet ja koalitio, jotka parhaimmillaan muodostavat toisiaan tukevan syklin. Keskijohdon rooli korostuu johtamisen ja operatiivisen toiminnan kokonaisuudessa.

Liikennemerkkien hankinta ja käänteinen huutokauppa

The aim of this study was to find out the benefits of centralized procurement. Research began with description of sourcing process and tools used in it. In this process the final tendering was done with e-auction. Due the fact that e-auction is unknown for most people, there is also need to explain when it can be used and what are the pros and cons. In the end of the study the pros and cons of the centralized sourcing process were analysed. This research was qualitative and that is why the results can’t be generalised to all other situations. Spend-analysis, Cost Break Down and Kraljic Matrix were used during the sourcing process. Process began with product group analysis- After that the financial and strategic significance was analysed. After analyses first quotations were asked and according to the results suppliers were eliminated and the selected ones were invited to e-auction. E-auction is an event where suppliers bid in a live online situation against each other to have the lowest current price. Benefits of it are fast sourcing process, discovering the true market price and information transparency. In the other hand the biggest problem comes from weakened supplier relationships. Average prices degreased 26 % from the 2009 price level and acquired price level was over 20 % lover that prices asked by individual projects. In a e-auction only moderate 1,34 % saving was acquired, but it also had other benefits as increasing the internal interest towards it.

Neural correlates of language learning in adults

The human language-learning ability persists throughout life, indicating considerable flexibility at the cognitive and neural level. This ability spans from expanding the vocabulary in the mother tongue to acquisition of a new language with its lexicon and grammar. The present thesis consists of five studies that tap both of these aspects of adult language learning by using magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) during language processing and language learning tasks. The thesis shows that learning novel phonological word forms, either in the native tongue or when exposed to a foreign phonology, activates the brain in similar ways. The results also show that novel native words readily become integrated in the mental lexicon. Several studies in the thesis highlight the left temporal cortex as an important brain region in learning and accessing phonological forms. Incidental learning of foreign phonological word forms was reflected in functionally distinct temporal lobe areas that, respectively, reflected short-term memory processes and more stable learning that persisted to the next day. In a study where explicitly trained items were tracked for ten months, it was found that enhanced naming-related temporal and frontal activation one week after learning was predictive of good long-term memory. The results suggest that memory maintenance is an active process that depends on mechanisms of reconsolidation, and that these process vary considerably between individuals. The thesis put special emphasis on studying language learning in the context of language production. The neural foundation of language production has been studied considerably less than that of perceptive language, especially on the sentence level. A well-known paradigm in language production studies is picture naming, also used as a clinical tool in neuropsychology. This thesis shows that accessing the meaning and phonological form of a depicted object are subserved by different neural implementations. Moreover, a comparison between action and object naming from identical images indicated that the grammatical class of the retrieved word (verb, noun) is less important than the visual content of the image. In the present thesis, the picture naming was further modified into a novel paradigm in order to probe sentence-level speech production in a newly learned miniature language. Neural activity related to grammatical processing did not differ between the novel language and the mother tongue, but stronger neural activation for the novel language was observed during the planning of the upcoming output, likely related to more demanding lexical retrieval and short-term memory. In sum, the thesis aimed at examining language learning by combining different linguistic domains, such as phonology, semantics, and grammar, in a dynamic description of language processing in the human brain.

One reason, several logics

Humans have used arguments for defending or refuting statements long before the creation of logic as a specialized discipline. This can be interpreted as the fact that an intuitive notion of "logical consequence" or a psychic disposition to articulate reasoning according to this pattern is present in common sense, and logic simply aims at describing and codifying the features of this spontaneous capacity of human reason. It is well known, however, that several arguments easily accepted by common sense are actually "logical fallacies", and this indicates that logic is not just a descriptive, but also a prescriptive or normative enterprise, in which the notion of logical consequence is defined in a precise way and then certain rules are established in order to maintain the discourse in keeping with this notion. Yet in the justification of the correctness and adequacy of these rules commonsense reasoning must necessarily be used, and in such a way its foundational role is recognized. Moreover, it remains also true that several branches and forms of logic have been elaborated precisely in order to reflect the structural features of correct argument used in different fields of human reasoning and yet insufficiently mirrored by the most familiar logical formalisms.

Formal semantics for propositional attitudes

Contemporary logic is confined to a few paradigmatic attitudes such as belief, knowledge, desire and intention. My purpose is to present a general model-theoretical semantics of propositional attitudes of any cognitive or volitive mode. In my view, one can recursively define the set of all psychological modes of attitudes. As Descartes anticipated, the two primitive modes are those of belief and desire. Complex modes are obtained by adding to primitive modes special cognitive and volitive ways or special propositional content or preparatory conditions. According to standard logic of attitudes (Hintikka), human agents are either perfectly rational or totally irrational. I will proceed to a finer analysis of propositional attitudes that accounts for our imperfect but minimal rationality. For that purpose I will use a non standard predicative logic according to which propositions with the same truth conditions can have different cognitive values and I will explicate subjective in addition to objective possibilities. Next I will enumerate valid laws of my general logic of propositional attitudes. At the end I will state principles according to which minimally rational agents dynamically revise attitudes of any mode.

Viestintä ravitsemusosaamisen kehittämisessä Case:Sairaalan ateriaprosessi

Tutkielman tarkoituksena oli tutkia viestinnän merkitystä osaamisen kehittämisessä. Tavoitteena oli tutkia, miten viestintä edistää ravitsemusosaamisen kehittämistä sairaalan ateriaprosessissa. Tutkimuksessa etsittiin vastausta kysymyksiin, mitkä ovat ravitsemusosaamisen kehittämisen ja viestinnän tavoitteet, millä työyhteisöviestinnän foorumeilla uuden ravitsemushoitosuosituksen ja ravitsemushoidon strategian edellyttämiä muutoksia käsitellään ja millaisia työssä oppimisen prosesseja näillä foorumeilla on tunnistettavissa. Empirian näkökulmasta tutkimusta voidaan kuvata tapaustutkimukseksi. Tapauksena on sairaalan ateriaprosessi. Tutkimuksen valmistelevana aineistona käytettiin uutta ravitsemushoitosuositusta (Nuutinen ym. 2010), jota täydennettiin haastatteluaineistolla. Tutkimuksessa ovat edustettuina hoitotyön, ruokapalvelun ja ravitsemushoidon asiantuntemuksen näkökulmat sairaalasta sekä ammatti- ja aikuisopistosta. Tutkimusmenetelmänä käytettiin teemahaastatteluja. Haastattelut nauhoitettiin ja litteroitiin tekstimuotoon. Aineisto analysoitiin teemakortiston ja teemoittelun avulla. Tutkimuksen tulokset osoittavat, että ravitsemusosaamisen kehittämisen tavoitteena on uuden ravitsemushoitosuosituksen ja ravitsemushoidon strategian edellyttämien muutosten toteuttaminen sairaalan ravitsemushoidon prosesseissa ja tuotteissa. Ravitsemusosaamisen kehittämisen tavoitteena on tässä yhteydessä ateriaprosessin ja ruokapalvelun tuotteiden eli ruokavalioiden kehittäminen. Ravitsemushoidon kehittämisen tarkoituksena on asiakkaiden toipumisen, elämänlaadun ja hyvinvoinnin edistäminen sekä terveydenhuollon kustannusten säästäminen. Viestinnällä on tärkeä merkitys ravitsemusosaamisen kehittämisessä. Viestinnän avulla edistetään yksilöllistä ja yhteistä eli tiimioppimista vuorovaikutuksen kautta. Ruokapalvelu- ja hoitohenkilöstön sekä ravitsemushoidon asiantuntijoiden välinen vuoropuhelu nähdään tärkeänä ravitsemusosaamisen kehittämisessä. Vuoropuhelun avulla vahvistetaan ravitsemushoitoon liittyvää tietopohjaa ja yhteistä käsitteistöä. Tavoitteena on yhteisen kielen ja toimintamallin luominen ravitsemushoidon kehittämiseen. Ravitsemushoitosuosituksen ja ravitsemushoidon strategian edellyttämiä muutoksia käsitellään ulkoisissa ja sisäisissä verkostoissa esimerkiksi ravitsemus-yhdyshenkilöverkoston tapaamisissa, moniammatillisissa työryhmissä, henkilöstö- ja oppisopimuskoulutuksissa sekä työfoorumilla eli fyysisessä työtilassa ja hyödyntäen viestintäteknologiaa. Hoitotyön, ruokapalvelun ja ravitsemushoidon asiantuntijoilla/opettajilla on tärkeä rooli ravitsemusosaamisen kehittämiseen liittyvässä työssä oppimisen ohjaamisessa. Ravitsemusosaamisen kehittämisessä on tunnistettavissa sosiaalisia, reflektiivisiä, kognitiivisia ja operationaalisia työssä oppimisen prosesseja. Sosiaalisia prosesseja ovat työkokemusten vaihdanta ja reflektiivisiä niiden arviointi. Kognitiivisten prosessien tarkoitus on tiedonhankinta ja prosessointi, jolloin yhdistetään kokemustietoa sekä uutta ravitsemustieteellistä tietoa. Tavoitteena on yhteisen kielen ja toimintamallin luominen, jota kokeillaan käytännössä. Operationaalisia prosesseja ovat fyysisessä työtilassa tapahtuva kokeilemalla, tekemällä ja soveltamalla oppiminen, jolloin uutta toimintamallia esimerkiksi vajaaravitsemuksen seulontaa, ateriatilausta tai reseptiikkaa kokeillaan käytännössä. Johtopäätöksenä voidaan todeta, että sairaalassa on omaksuttu oppivan organisaation periaatteita ravitsemusosaamisen kehittämisessä. Ravitsemusosaamisen kehittäminen on yhteydessä muutokseen, strategiaan, prosessien ja tuotteiden kehittämiseen. Viestinnän avulla edistetään ravitsemushoitosuosituksen ja ravitsemushoidon strategian edellyttämien muutosten toteuttamista sairaalan ateriaprosessissa ja ruokavalioissa. Hoito- ja ruokapalveluhenkilöstön sekä ravitsemushoidon asiantuntijoiden välisen vuoropuhelun tavoitteena on yhteisen kielen ja toimintamallin luominen ravitsemushoidon kehittämiseen. Tutkimus palvelee ravitsemusosaamisen kehittämistä sairaalan ateriaprosessissa. Tutkimuksen tuloksia on mahdollista käyttää vertailuoppimismateriaalina terveydenhuollon organisaatioissa ja verkostoissa.