821 resultados para Visible cutoff values


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Principal component analysis (PCA) is a chemometric method that allows for the extraction of chemical information that would otherwise be impossible to determine. Teaching chemometrics to undergraduates can contribute to the overall professional development and training of new teachers, whose profiles have been gaining attention due to the current demand for data interpretation. In this study, a didactic experiment involving PCA is proposed. Spectrophotometry was used in the ultraviolet-visible (UV-Vis) region to assess the behavior of anthocyanins extracted from red cabbage at different pH values. The results suggest the possible separation of anthocyanin structures into three distinct groups, according to their chemical characteristics displayed in acid, neutral, and basic media. The objective is to develop educational materials targeted to undergraduate courses, which encompass a larger number of concepts and introduce instrumental techniques currently being employed in both academic research and the industrial sector. Specifically, the proposed experiment introduces concepts related to spectrophotometry in the UV-Vis range and the PCA chemometric method. The materials used are easily accessible, and UV-Vis spectroscopy equipment is less expensive in comparison with other spectroscopy methods.

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The deterioration of surface waters is one of the most important issues in the environmental management of the European Union. Thus, the EU Water Framework Directive 2000/60/EC (WFD) requires “good ecological and chemical status” of surface waters by 2015 allowing only a slight departure from ecological reference conditions characterized by the biological communities typical for the conditions of minimal anthropogenic impact. The WFD requires the determination of ecological reference conditions and the present ecological status of surface waters. To meet this legislative demand, sedimentary diatom assemblages were used in these studies with various methods 1) to assess natural and human activity induced environmental changes, 2) to characterize background conditions 3) to evaluate the present ecological status and 4) to predict the future of the water bodies in the light of palaeolimnological data. As the WFD refers to all surface waters, both coastal and inland sites were included. Two long and two short sediment cores from the Archipelago Sea in the northern Baltic Sea were examined for their siliceous microfossils in order to assess (1) the Holocene palaeoenvironmental history and (2) the recent eutrophication of the area. The diatom record was divided into local diatom assemblage zones (LDAZ, long cores) and diatom assemblage zones (DAZ, short cores). Locally weighted weighted averaging regression and calibration (LWWA) was applied for the quantitative reconstruction of past TN concentrations (short cores). An age model for the long cores was constructed by using independent palaeomagnetic and AMS-14C methods. The short cores were dated using radiometric (210Pb, 226Ra and 137Cs) methods. The long cores date back to the early history of the Archipelago Sea, which was freshwater – no salinity increase referable to the brackish phase of the Yoldia Sea is recognized. The nutrient status of the lacustrine phase was slightly higher in the Archipelago Sea than in the Baltic Proper. Initial brackish-water influence is observed at 8 150 ±80 cal. BP (LDAZ4), but fully brackish conditions were established at 7 700 ±80 cal. BP (LDAZ5). The diatom assemblages indicate increasing salinity, warming climate and possible eutrophic conditions during the lacustrine to brackish-water transition. The decreasing abundance of Pseudosolenia calcar-avis (Schultze) Sundström and the increasing abundance of the ice-cover indicator species Pauliella taeniata (Grunow) Round and Basson indicate decreasing salinity and climatic cooling after ca. 5 000 cal. BP. Signs of eutrophication are visible in the most recent diatom assemblage zones of both short cores. Diatom-inferred total nitrogen (DI-TN) reconstructions partially fail to trace the actual measured total nitrogen concentrations especially from the late 1980s to the mid 1990s. This is most likely due to the dominating diatom species Pauliella taeniata, Thalassiosira levanderi Van Goor and Fragilariopsis cylindrus (Grunow) W. Krieger being more influenced by factors such as the length of the ice-season rather than nutrient concentrations. It is concluded that the diatom assemblages of the study sites are principally governed by climate fluctuations, with a slight influence of eutrophication visible in the most recent sediments. There are indications that global warming, with reduced ice cover, could impact the spring blooming diatom species composition in the Archipelago Sea. In addition, increased sediment accumulation in the early 90s coincides with the short ice-seasons suggesting that warming climate with decreasing ice-cover may increase sedimentation in the study area. The diverse diatom assemblages dominated by benthic species (54 %) in DAZ1 in the Käldö Fjärd core can be taken as background diatom assemblages for the Archipelago Sea. Since then turbidity has increased and the diatom assemblages have been dominated by planktonic diatoms from around the mid 1800s onwards. The reconstructed reference conditions for the total nitrogen concentrations fluctuate around 400 μg l-1. Altogether two short sediment cores and eight short cores for top-bottom analysis were retrieved from Lake Orijärvi and Lake Määrjärvi to assess the impact of the acid mine drainage (AMD) derived metals from the Orijärvi mine tailings on the diatom communities of the lakes. The Cu (Pb, Zn) mine of Orijärvi (1757 – 1956) was the first one in Finland where flotation techniques (1911 – 1955) were used to enrich ore and large quantities of tailings were produced. The AMD derived metal impact to the lakes was found to be among the heaviest thus far recorded in Finland. Concentrations of Cu, Pb and Zn in Lake Orijärvi sediments are two to three orders of magnitude higher than background values. The metal inputs have affected Lake Orijärvi and Lake Määrjärvi diatom communities at the community levels through shifts in dominant taxa (both lakes) and at the individual level through alteration in frustule morphology (Lake Orijärvi). At present, lake water still has elevated heavy metal levels, indicating that the impact from the tailings area continues to affect both lakes. Lake Orijärvi diatom assemblages are completely dominated by benthic species and are lacking planktonic diatoms. In Lake Määrjärvi the proportion of benthic and tychoplanktonic diatoms has increased and the planktonic taxa have decreased in abundance. Achnanthidium minutissimum Kützing and Brachysira vitrea (Grun.) R. Ross in Hartley were the most tolerant species to increased metal concentrations. Planktonic diatoms are more sensitive to metal contamination than benthic taxa, especially species in the genus Cyclotella (Kützing) Brébisson. The ecological reference conditions assessed in this study for Lake Orijärvi and Lake Määrjärvi comprise diverse planktonic and benthic communitites typical of circumneutral oligotrophic lakes, where the planktonic diatoms belonging to genera Cyclotella , Aulacoseira Thwaites, Tabellaria Ehrenberg and Asterionella Hassall dominate in relative abundances up to ca. 70%. The benthic communities are more diverse than the planktonic consisting of diatoms belonging to the genera Achnanthes Bory, Fragilaria Lyngbye and Navicula St. Vincent. This study clearly demonstrates that palaeolimnological methods, especially diatom analysis, provide a powerful tool for the EU Water Frame Work Directive for defining reference conditions, natural variability and current status of surface waters. The top/bottom approach is a very useful tool in larger-scale studies needed for management purposes. This “before and after” type of sediment sampling method can provide a very time and cost effective assessment of ecological reference conditions of surface waters.

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Flow injection (FI) methodology, using diffuse reflectance in the visible region of the spectrum, for the analysis of total sulfur in the form of sulfate, precipitated in the form of barium sulfate, is presented. The method was applied to biodiesel, to plant leaves and to natural waters analysis. The analytical signal (S) correlates linearly with sulfate concentration (C) between 20 and 120 ppm, through the equation S=-1.138+0.0934 C (r = 0.9993). The experimentally observed limit of detection is about 10 ppm. The mean R.S.D. is about 3.0 %. Real samples containing sulfate were analyzed and the results obtained by the FI and by the reference batch turbidimetric method using the statistical Student's t-test and F-test were compared.

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The combination of two low-cost classical procedures based on titrimetric techniques is presented for the determination of pyridoxine hydrochloride in pharmaceuticals samples. Initially some experiments were carried out aiming to determine both pKa1 and pKa2 values, being those compared to values of literature and theoretical procedures. Commercial samples containing pyridoxine hydrochloride were electrochemically analysed by exploiting their acid-base and precipitation reactions. Potentiometric titrations accomplished the reaction between the ionizable hydrogens present in pyridoxine hydrochloride, being NaOH used as titrant; while the conductimetric method was based on the chemical precipitation between the chloride of pyridoxine hydrochloride molecule and Ag+ ions from de silver nitrate, changing the conductivity of the solution. Both methods were applied to the same commercial samples leading to concordant results when compared by statistical tests (95 and 98% confidence levels). Recoveries ranging from 99.0 to 108.1% were observed, showing no significant interference on the results.

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The home as ethos, an ethical dimension of human beings, is this study’s focus of interest. Can the home as ethos comprise motive and driving force for a human being? This dissertation has a mainly hermeneutic approach with a Caring Science interpretive horizon. Firstly, the purpose of this study is to develop the concept “home” through etymological and semantic analysis. The concept’s Caring Science content is also investigated. Secondly, the purpose of this study is to investigate, through the use of a history of ideas method, how the home as ethos is made visible and evident in public health nurses’ caring during the first half of the 20th century. Which motives compromise the driving force behind public health nurses’ caring? Which idea patterns are stressed? Material for the study’s concept determination consists of tymological dictionaries as well as Swedish language dictionaries published from 1850 – 2001. The results of the concept determination provide a preliminary idea-model, where dimensions such as ethos as a human being’s innermost room, human beings’ manner of being, and the metaphor “my home is my castle” are stressed. These results comprise the background of the history of ideas portion of the study. The study’s history of ideas investigation occurs through the evaluation and interpretation of historical sources focusing on the caring provided by public health nurses. Public health nurses comprise both the context and prevalent traditions during the time-period studied. The historical sources consist of three different types of sources, namely textbooks, archived material, and the professional nursing journals Epione and Sairaanhoitajatarlehti. The purpose is to rediscover fundamental idea-patterns through the thematic structuring of the patterns appearing in the historical sources. Three main idea-patterns and underlying themes are rediscovered: love- a fire which burns inside human beings; reverence for human beings and home; and the honor of responsibility. The emerging patterns are tightly interwoven and form a pattern. A new interpretation occurs, widening the study’s horizon and leading to the emergence of the theory-model’s contours. The study’s theory-model is formed from three different levels. Ethos as a human being’s innermost room- the spirit, encompasses a human being’s value base and the spirit that he/she is permeated with. Fundamental values are converted into an internal ethic, becoming visible in human beings’ manner of being- the manner of conduct. The metaphor “my home is my castle”- the tone, symbolizes the room where a human being’s abstract or concrete being lives. The spirit, the ethos, is expressed in a home’s culture and atmosphere, that is to say the tone of a home or how one lives in a room. Communion is a significant component in the creation of a culture and atmosphere. This study’s theory-model gives rise to a new perspective that can generate new patterns of action. The study’s theory-model results in a new historically-based view that create new patterns of action in care and Caring Science today.

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Denna vårdvetenskapliga avhandling syftar till att avtäcka och belysa en vårdande och helande dimension vid existentiellt lidande patienters möten med bildkonst inom vårdkontext. Kunskapssökandet sker i två studier. Den första (studie I) är en ikonografi sk tolkning av konstnären Matthias Grünewalds (ca 1460–1528) senmedeltida altarskåpsmålningar. I studien uttolkas lidandets uttryck och narrativa budskap samt symboliska gestaltningar av vårdande och helande i valda delar av detta s.k. Isenheimaltares bildprogram. Tolkningen utgår från rekonstruktionen av altarskåpets ursprungskontext, det medeltida Isenheimklostret, där svårt sjuka och döende patienter vårdades. I studie två (II) fortsätter sökandet i den moderna hospicevårdens kontext med hjälp av en kvalitativ intervjustudie som utforskar patienters meningsskapande vid möten med självvald bildkonst (oljemålningar och akvareller av fi nländska konstnärer som donerats till det sjukhus där intervjustudien gjordes). Forskningsansatsen är inspirerad av Hans-Georg Gadamers (1901–2002) hermeneutik. Vidare används några nyare tolkningsteoretiska ansatser inom bildkonstens område. Forskningens tolkningsresultat visar att bildkonsten har potentialer såväl på ett miljöestetiskt plan som på en djupare individuell symbolnivå. Som designkomponent i vårdmiljöns rumsliga gestaltning bygger bildkonsten in estetiska, etiska och andliga kvaliteter utifrån tidsmässiga och kulturella koder. I den medeltida klostervårdens kontext sammanföll bildkonstens dekorativa betydelse med andliga och helande syften. När det gäller självvalda konstverk i den moderna vårdkontexten bidrar de till det enskilda patientrummets atmosfär på ett unikt sätt utifrån patientens personlighet och behov. På en fördjupad mötesnivå, i samspel med bildens symboliska funktion, sker en inlevelsemässig förfl yttning in i bildens värld. Betraktarens inlevelse aktiveras till en transcenderande rörelse som går bortom det faktiska rummets och den reella tidens gränser. Vid resor i konstens bildvärld spelas minnesvärda händelser upp från det förgångna, men även framtiden kommer betraktaren till mötes. I en existentiell livssituation söker människan i konstverkets bildinnehåll efter symbolisk mening som kan ge svar på lidandets frågor. Bilderna iscensätter då helande motbilder som utgör korrektiv i symboliska former när olika existentiella förluster hotar. När livet förbleknats av sjukdom besvarar bildvärlden den lidandes blick med lysande violer som blommar upp, ger livskraft och bekräftar personens värdighet mitt i det förvissnande människolivet. När ångest och otrygghet nalkas inbjuds betraktaren till besök i landskap som utvidgar sjukhusrummets väggar mot hemgårdens trygghet. Där livet hotas av förgänglighet tar bildvärlden människan med sig till naturens eviga återfödelse. Upplevelsen av att vara delaktig i ett större och heligt sammanhang öppnar vägen ut ur lidandets avskurenhet. I medeltidens vårdkontext erbjöd den sakrala bilden en kollektiv och helande Symbolon som genom sin representationskraft synliggjorde det osynliga. Vid bildmöten i den moderna hospicevårdens kontext var det naturteman som gläntade på dörren till ”det hemliga rummet i djupet av hjärtat”. Forskningen antyder att även om meningsskapandet i ett bildmöte är avhängigt tidsepok, betraktarens förförståelse och kulturella kontext samt typen av bilder kan bildsymboliken, generellt förstådd som den saknade formen eller det saknade livssammanhanget, framvisa en helande och hoppingivande ordning i lidandets kaos.

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The purpose of this thesis is to study organizational core values and their application in practice. With the help of literature, the thesis discusses the implementation of core values and the benefits that companies can gain by doing it successfully. Also, ways in which companies can improve their values’ application to their everyday work are presented. The case company’s value implementation is evaluated through a survey research conducted on their employees. The true power of values lies in their application, and therefore, core values should be the basis for all organizational behavior, integrated into everything a company does. Applying values in practice is an ongoing process and companies should continuously work towards creating a more value-based organizational culture. If a company does this effectively, they will most likely become more successful with stakeholders as well as financially. Companies looking to turn their values into actions should start with a self-assessment. Employee surveys are effective in assessing the current level of value implementation, since employees have valuable, first-hand information regarding the situations and behaviors they face in their everyday work. After the self-assessment, things like management commitment, communication, training, and support are key success factors in value implementation.

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Bakgrund Demokratiska samhällen är sårbara och historiskt sett sällsynta. Förutsättningarna för en fungerande demokrati innefattar mer än formella institutioner eller enbart frånvaron av diktatorer och extremgrupper. För att en regim skall fungera enligt demokratiska principer behövs medborgare som stöder demokratiska värden. Därför är det av vikt att förstå de processer som får individer att känna tilltro till demokratiska värden. Trots att man kan anta att stöd för sådana värderingar utvecklas som ett resultat av social inlärning är de konkreta omständigheterna som leder till ett dylikt lärande mindre uppenbara. Den klassiska litteraturen beträffande politisk socialisation lyfte fram föräldrarna som avgörande för de ungas medborgerliga fostran, men i moderna samhällen har föräldrarna sällan som en uttalad målsättning att försöka påverka sina barns nuvarande eller framtida politiska preferenser. Den föreliggande studiens mål var att fördjupa diskursen kring politisk socialisation gen om att analysera föräldraskapets betydelse för demokratiska värderingar hos ungdomar. Metod Den föreliggande studien utgick från två slumpmässiga urval. Det ena omfattade 1341 studerande, 17 år gamla, inom andra stadiets utbildning i tre regioner i Finland (södra, syd-västra och västra) och det andra 678 studerande, 16 år gamla vid studiens inledande, från den flamländska delen av Belgien. Studien innefattade frågeformulär som besvarades under skoltid. Resultat De centrala resultaten från studien kan sammanfattas i fyra punkter. För det första kunde empatiskt tänkande konstateras vara en god förklarande variabel för ungdomars demokratiska värderingar (Artikel 1). För det andra gav studien stöd för antagandet att stödjande föräldraskap är av betydelse för utvecklingen av empati under ungdomsåren (Artikel 2). För det tredje utvärderades empati, i relation till andra betydelsefulla variabler, som förklarande variabel för demokratiska värderingar (Artikel 3). För det fjärde gav den föreliggande studien bevis för att demokratiskt föräldraskap, både direkt och indirekt, är relaterat till demokratiska värderingar hos ungdomar. Sammanfattning Sammanfattningsvis visade den föreliggande studien hur föräldraskap både direkt och indirekt kan påverka demokratiska värderingar hos ungdomar och hur dessa resultat kunde användas för demokratisk samhällsfostran.

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Citrus orchards are very important in Brazil, especially in São Paulo State, where occupy an area of 600,000 ha approximately. To identify sustainability degree of citrus production system, an energy analysis allows evaluating efficiency of direct and indirect applied inputs. Thus, this study aimed to evaluate citrus production system under energetic point of view, in which invested energy is paid back with citrus production; being compared within three scenarios for operational field efficiency. As result, by sensitivity analysis was determined that fuel was the main energy demander, followed by pesticides and fertilizers. In operational work capacity analysis, all combinations between efficiency (minimum, typical and maximum) and yield levels became positive in the seventh year, except for the combination minimum efficiency and 10 % less yield, positive in the eighth year. The best combination (maximum efficiency and 10 % more yield) has promoted investment payoff around the sixth and seventh year. By this study, it is possible to determine the total energy demand to produce citrus and indentify the applied inputs that need more attention by the decision-makers. Labor and seedlings can be ommited for further studies with citrus, since they were irrelevant. Management of agricultural machinery may pose an important role on decreasing environmental impact of citrus production.

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In my doctoral thesis I evaluate strategies designed to cope with the multicultural nature of four European nations: Great Britain, The Netherlands, Sweden, and Denmark. I also analyse and clarify the question of the place of religion in present-day Europe. The empirical material analysed in the study consists of politicians’ statements and policy documents dealing with immigration policy and religious and values education in the four countries. In addition, I analyse statements issued by the Council of Europe regarding religious education, along with all cases relevant to religious education brought before the United Nations Human Rights Committee or the European Court of Human Rights. The theoretical framework is formed by the scholarly debate – among philosophers, sociologists and scholars of religion in education – concerning the question of a just society. Special emphasis is given to philosophical theories that are in favour of granting special group rights to religious minorities in the name of equal treatment. With regard to the question of the appropriate place of religion, I apply Kim Knott’s methodological model for locating religion in secular contexts, and Émile Durkheim’s theory as to the significance of religion and collective sentiments in uniting adherents or members of a group into a single moral community. The study shows that even when the positive side of immigration, as a potential force for the enrichment of the public culture, is acknowledged, there is anxiety as to the successful integration of immigrants. The premises and goals of immigration policies have also been questioned. One central problem is the incommensurability between the values upheld by Western liberal democracies and certain religious traditions, above all those of Islam. Great Britain, The Netherlands, Sweden, and Denmark have tightened control over their citizens’ ethical attitudes and want to regulate these as well. In coping with cultural diversity, the significance of education, especially religious education, plays a significant role; as future citizens, pupils are expected to internalise the society’s core values as well as gaining an understanding of different cultures and ways of life. It is also worth noting that both the Council of Europe and the European Court of Human Rights have recently expressed the view that one important goal of religious education is to enable pupils to be critical and autonomous with regard to different religions and moral positions. The study shows that religion is not seen as purely a personal matter. Religion is closely linked to individual and national identity, and religious traditions thus have a place in the public domain. It should be noted, however, that a religious tradition – more precisely, an interpretation of religious tradition – qualifies as a legitimate partner in the democratic decision-making process only if it shares similar values with Western European nations.