Neoproterozoic geodynamic evolution of SW-Gondwana: a southern African perspective

Our current understanding of the tectonic history of the principal Pan-African orogenic belts in southwestern Africa, reaching from the West Congo Belt in the north to the Lufilian/Zambezi, Kaoko, Damara, Gariep and finally the Saldania Belt in the south, is briefly summarized. On that basis, possible links with tectono-stratigraphic units and major structures on the eastern side of the Rio de la Plata Craton are suggested, and a revised geodynamic model for the amalgamation of SW-Gondwana is proposed. The Rio de la Plata and Kalahari Cratons are considered to have become juxtaposed already by the end of the Mesoproterozoic. Early Neoproterozoic rifting led to the fragmentation of the northwestern (in today`s coordinates) Kalahari Craton and the splitting off of several small cratonic blocks. The largest of these ex-Kalahari cratonic fragments is probably the Angola Block. Smaller fragments include the Luis Alves and Curitiba microplates in eastern Brazil, several basement inliers within the Damara Belt, and an elongate fragment off the western margin, named Arachania. The main suture between the Kalahari and the Congo-So Francisco Cratons is suspected to be hidden beneath younger cover between the West Congo Belt and the Lufilian/Zambezi Belts and probably continues westwards via the Cabo Frio Terrane into the Goias magmatic arc along the Brasilia Belt. Many of the rift grabens that separated the various former Kalahari cratonic fragments did not evolve into oceanic basins, such as the Northern Nosib Rift in the Damara Belt and the Gariep rift basin. Following latest Cryogenian/early Ediacaran closure of the Brazilides Ocean between the Rio de la Plata Craton and the westernmost fragment of the Kalahari Craton, the latter, Arachania, became the locus of a more than 1,000-km-long continental magmatic arc, the Cuchilla Dionisio-Pelotas Arc. A correspondingly long back-arc basin (Marmora Basin) on the eastern flank of that arc is recognized, remnants of which are found in the Marmora Terrane-the largest accumulation of oceanic crustal material known from any of the Pan-African orogenic belts in the region. Corresponding foredeep deposits that emerged from the late Ediacaran closure of this back-arc basin are well preserved in the southern areas, i.e. the Punta del Este Terrane, the Marmora Terrane and the Tygerberg Terrane. Further to the north, present erosion levels correspond with much deeper crustal sections and comparable deposits are not preserved anymore. Closure of the Brazilides Ocean, and in consequence of the Marmora back-arc basin, resulted from a change in the Rio de la Plata plate motion when the Iapetus Ocean opened between the latter and Laurentia towards the end of the Ediacaran. Later break-up of Gondwana and opening of the modern South Atlantic would have followed largely along the axis of the Marmora back-arc basin and not along major continental sutures.

The Cariris Velhos tectonic event in Northeast Brazil

The Borborema Province in northeastern South America is a typical Brasiliano-Pan-African branching system of Neoproterozoic orogens that forms part of the Western Gondwana assembly. The province is positioned between the Sao Luis-West Africa craton to the north and the Sao Francisco (Congo-Kasai) craton to the south. For this province the main characteristics are (a) its subdivision into five major tectonic domains, bounded mostly by long shear zones, as follows: Medio Coreau, Ceara Central, Rio Grande do Norte, Transversal, and Southern; (b) the alternation of supracrustal belts with reworked basement inliers (Archean nuclei + Paleoproterozoic belts); and (c) the diversity of granitic plutonism, from Neoproterozoic to Early Cambrian ages, that affect supracrustal rocks as well as basement inliers. Recently, orogenic rock assemblages of early Tonian (1000-920 Ma) orogenic evolution have been recognized, which are restricted to the Transversal and Southern domains of the Province. Within the Transversal Zone, the Alto Pajeu terrane locally includes some remnants of oceanic crust along with island arc and continental arc rock assemblages, but the dominant supracrustal rocks are mature and immature pelitic metasedimentary and metavolcaniclastic rocks. Contiguous and parallel to the Alto Pajeu terrane, the Riacho Gravata subterrane consists mainly of low-grade metamorphic successions of metarhythmites, some of which are clearly turbiditic in origin, metaconglomerates, and sporadic marbles, along with interbedded metarhyolitic and metadacitic volcanic or metavolcaniclastic rocks. Both terrane and subterrane are cut by syn-contractional intrusive sheets of dominantly peraluminous high-K calc-alkaline, granititic to granodioritic metaplutonic rocks. The geochemical patterns of both supracrustal and intrusive rocks show similarities with associations of mature continental arc volcano-sedimentary sequences, but some subordinate intra-plate characteristics are also found. In both the Alto Pajeu and Riacho Gravata terranes, TIMS and SHRIMP U-Pb isotopic data from zircons from both metavolcanic and metaplutonic rocks yield ages between 1.0 and 0.92 Ga, which define the time span for an event of orogenic character, the Cariris Velhos event. Less extensive occurrences of rocks of Cariris Velhos age are recognized mainly in the southernmost domains of the Province, as for example in the Polo Redondo-Maranco terrane, where arc-affinity migmatite-granitic and meta-volcano-sedimentary rocks show U-Pb ages (SHRIMP data) around 0.98-0.97 Ga. For all these domains, Sm-Nd data exhibit Tom model ages between 1.9 and 1.1 Ga with corresponding slightly negative to slightly positive epsilon(Nd)(t) values. These domains, along with the Borborema Province as a whole, were significantly affected by tectonic and magmatic events of the Brasiliano Cycle (0.7-0.5 Ga), so that it is possible that there are some other early Tonian rock assemblages which were completely masked and hidden by these later Brasiliano events. Cariris Velhos processes are younger than the majority of orogenic systems at the end of Mesoproterozoic Era and beginning of Neoproterozoic throughout the world, e.g. Irumide belt, Kibaride belt and Namaqua-Natal belt, and considerably younger than those of the youngest orogenic process (Ottawan) in the Grenvillian System. Therefore, they were probably not associated with the proposed assembly of Rodinia. We suggest, instead, that Cariris Velhos magmatism and tectonism could have been related to a continental margin magmatic arc, with possible back-arc associations, and that this margin may have been a short-lived (<100 m.y.) leading edge of the newly assembled Rodinia supercontinent. (C) 2009 Elsevier Ltd. All rights reserved.

Relics of eclogite facies assemblages in the Ceara Central Domain, NW Borborema Province, NE Brazil: Implications for the assembly of West Gondwana

The Borborema Province, in the NE of Brazil, is a rather complex piece in the Brazil-Africa puzzle as it represents the junction of the Dahomeyide/Pharusian, Central African, Aracuai and Brasilia fold belts located between the West-African/Sao Luis, Congo/Sao Francisco and Amazonas craton. The correlation between the Dahomeyides from W-Africa (Ghana, Benin, Togo, and Mali) and the Borborema Province involves the Medio Coreau and Central Ceara domains. The inferred continuation of the main oceanic suture zone exposed in the Dahomeyides of W Africa is buried beneath the Phanerozoic Parnaiba Basin in Brazil (northwest of the Medio Coreau domain) where some high density gravity anomalies may represent hidden remnants of an oceanic suture. In addition to this major suture a narrow, nearly continuous strip composed of mainly mafic pods containing relics of eclogite-facies assemblages associated with partially migmatized granulite-facies metapelitic gneisses has been found further east in the NW Borborema Province. These high pressure mafic rocks, interpreted as retrograded eclogites, are located between the Transbrasiliano Lineament and the Santa Quiteria continental arc and comprise primitive to evolved arc-related rocks with either arc- or MORB-type imprints that can indicate either deep subduction of oceanic lithosphere or roots of continental and oceanic magmatic arcs. Average peak P-T conditions under eclogite-facies metamorphism (T=770 degrees C and P = 17.3 kbar) were estimated using garnet-clinopyroxene thermometry and Jd content in clinopyroxene. Transition to granulite-facies conditions, as well as later widespread re-equilibration under amphibolite facies, were registered both in the basic and the metapelitic rocks and suggest a clockwise P-T path characterized by an increase in temperature followed by strong decompression. A phenomenon possibly related to the exhumation of a highly thickened crust associated with the suturing of the Medio Coreau and Central Ceara domains, two distinct crustal blocks separated by the Transbrasiliano Lineament. (C) 2009 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Chemical variability within the marine sponge Aplysina fulva

Dibromotyrosine-derived metabolites are of common occurrence within marine sponges belonging to the order Verongida. However, previous chemical analysis of crude extracts obtained from samples of the verongid sponge Aplysina fulva collected in Brazil did not provide any dibromotyrosine-derived compounds. In this investigation, five samples of A. fulva from five different locations along the Brazilian coastline and one sample from a temperate reef in the South Atlantic Bight (SAB) (Georgia, USA) were investigated for the presence of bromotyrosine-derived compounds. All six samples collected yielded dibromotyrosine-derived compounds, including a new derivative, named aplysinafulvin, which has been identified by. analysis of spectroscopic data. These results confirm previous assumptions that dibromotyrosine-derived metabolites can be considered as chemotaxonomic markers of verongid sponges. The isolation of aplysinafulvin provides additional support for a biogenetic pathway involving an arene oxide intermediate in the biosynthesis of Verongida metabolites. It cannot yet be established if the chemical variability observed among the six samples of A.fulva collected in Brazil and the SAB is the result of different environmental factors, distinct chemical extraction and isolation protocols, or a consequence of hidden genetic diversity within the postulated morphological plasticity of this species. (C) 2007 Elsevier Ltd. All rights reserved.

Kriminalitetens geografi : vardagsbrottslighetens spatiala fördelning i Borlänge

The aim of this thesis is to describe and analyze the geographical distribution of everyday criminality in the town of Borlänge during the year 2002 and to analyze which measures to be taken in the physical social planning to decrease this everyday criminality there. The term everyday criminality is here to be understood as those categories of crime that appear most frequently in the records of reports to the police every year. Here two kinds of crime have been in focus, thefts from cars and office burglary.In fulfilling this aim two main questions have been answered. The first one is how the everyday criminality was distributed geographically in the town of Borlänge during the year 2002. The second one is which measures to be taken in the physical social planning to decrease this everyday criminality in the town of Borlänge.In order to answer the first question a spatial autocorrelation analysis, Local Moran LISA has been used. This method is based on the measurement Moran´s I and shows the spatial autocorrelation for every single location. To answer the second question three different theories of crime prevention through environmental design have been studied and applied in the analysis. These are Jane Jacobs’ ideas about ”the living city”, Oscar Newman´s ideas about ”defensible space” and Ronald V. Clarke´s theories about crime prevention.The major conclusions that can be drawn from this thesis are that the risk of being exposed to thefts from cars, during the analyzed time period, was highest in Centrum and Hagalund and their surroundings. The lowest risk of being exposed to this type of crime was found in Domnarvet and Islingby, during the year 2002. The highest risk of being a victim of the crime office burglary was found in Hagalund and its surroundings and in the single area of Kvarnsveden. The corresponding lowest risk was found in Lergärdet and its surroundings and in Norra Backa and Kupolen. The measures that should be taken in order to decrease these types of criminality can be divided into overall changes and place-specific changes. When it comes to the crime thefts from cars a more attractive central business district, a better view of parking lots from nearby buildings, dividing of larger parking lot zones into smaller ones, migration of hidden parking lots and stronger access control to parking lots where problems with this kind of crime have occurred have been suggested as overall changes. The corresponding place-specific changes are to remove vegetation that is blocking the view, better lighting and to put up signs with information about increased risk of exposure to crime at parking lots with the most problems. To decrease the amount of office burglaries overall changes as to create a better view of the area from nearby surroundings, move bigger office compartments or divide them into smaller units, rebuild characteristic buildings and increase security by strengthening the access control to offices with these kinds of problems could be useful. Finally there are possibilities to decrease office burglary by using place-specific measures as surveillance cameras combined with signs containing information about these, high fences and better lighting around the buildings where a higher risk of being exposed to this kind of criminality is present.

Power Management Controls

In an office building in the US the office equipment uses about 7% of the total electricity use. Eventhough this is a low number, there is still a reason to save more energy, especially since one third of theenergy savings are lost when power management is not enabled.The core in the project ”Power Management Controls” is to develop a voluntary standard, The UserInterface Standard, that manufacturers of office equipment can use as a reference when they developnew equipment and design new interfaces. The interface is an important part of the use of powermanagement and doing this should increase the use of power management and save more energy. Theinterfaces are ofter hidden or inconsistent and confusing, which makes it harder for the user tounderstand power management. A more consistent interface makes it easier for the user to understandthe meaning of an interface and power management itselfThe standard consists of six different parts, which describe what can be done to achieve a consistentinterface. The standard also describes the part of the project called Dynamic Behavior. This part isconcentrating on the interfaces and the behavior of the device over time, which is important for the userto understand.The purpose of this degree project is to study and participate in the project ”Power ManagementControls”, and to understand what is being done to save more energy.

Kunskapsöverföring- att leda rätt : Ledarens roll vid kunskapsöverföring i en organisation

I en rapport som Svensk Näringsliv (2010) har utfört beskriver de att företag redan idag och inom en snar framtid står inför den största pensionsavgången någonsin i Svensk historia. 40- talisternas avgång ställer företag inför stora utmaningarna, framförallt att lyckas genomföra en lyckad generationsväxling. De personer som går i pension har under sitt yrkesverksamma liv utvecklat en kunskap som många organisationer vilar på. En stor del av denna kunskap måste överföras för att organisationerna ska kunna fortsätta att vara effektiva på marknaden. Syftet med denna studie var att få en djupare förståelse för ledarskapets betydelse gällande kunskapsöverföring i en organisation, samt bidra med praktiska verktyg till chefer och medarbetare för att undvika att förlora värdefull kunskap vid en generationsväxling. Industriföretaget LEAX har själva identifierat ett problem i att överföra viktig kunskap i och med kommande generationsväxling. Deras önskan var att få hjälp med praktiska verktyg för hur de ska tänka och verka för att mildra kunskapsglappet som kan uppstå. För att undersöka detta och därmed uppfylla denna studies syfte har intervjuer genomförts med fyra produktionsledare, fyra medarbetare som förväntas dela kunskap och tre medarbetare som förväntas ta till sig kunskap. Innan intervjuerna genomfördes läste vi in oss på teori om kunskap, kunskapsöverföring och ledarskap. Eftersom begreppet kunskap har en bred betydelse och kan definieras olika beroende om den är individuell eller organisatorisk, började vi i vårt teoriavsnitt att bena ut detta begrepp. Nonaka och Takeuchi (1995) gör en förenklad bild av kunskap som ett isberg, där den explicita kunskapen benämns som toppen. Väl synlig över ytan på vattnet är den enkel att upptäcka och ta till sig. Under vattnet döljer sig en osynlig kunskap som är svår att upptäcka, så kallas implicit eller tyst kunskap. Denna kunskap utgör en enorm del av isberget och blir därmed viktig att bevara. Dock är denna kunskap svår att överföra då den är osynlig och svår att ta på. För att förstå vad kunskapsöverföring innebär, behöver organisationer identifiera vilken sorts kunskap som behöver överföras för att kunskapsöverföringen ska bli lyckad (Jonsson, 2012). Men även fast organisationer gör detta måste även ledningen förstå att kunskapsöverföring är en strategisk angelägenhet som kan ses som en process som involverar medarbetare. I denna studie har vi undersökt hur ledare kan skapa motivation, engagemang och resurser för medarbetare att vilja medverka och bidra till kunskapsöverföring. För att försöka förstå hur kunskap överförs i en organisation har vi använt oss av Nonaka och Takeuchi, (1995) SECI-modell. Modellen bygger på samspelet mellan den tysta och explicita kunskapen, vilket sker i fyra processer. Dessa processer har vi sedan utvecklat till en egen modell som inkluderar institutionella, organisatoriska och kognitiva faktorer. Utifrån dessa faktorer har vi skapat praktiska förslag på hur ledare tillsammans med medarbetarna kan planera kunskapsöverföring. Dessa praktiska förslag gynnar både individuell- och organisatorisk utveckling, samt bidrar till att mildra kunskapsförlust vid generationsväxlingen. Ett av de praktiska exempel vi utformat är en kompetensprofil, som är ett hjälpmedel för organisationer att identifiera vilken kunskap som medarbetarna besitter, vilket synliggör vilken kunskap det är som kan gå förlorad. Kompetensprofilen tillsammans med vår modell kan appliceras på liknande företag, men även på organisationer som verkar inom andra branscher. Eftersom denna kompetensprofil är utvecklad efter de krav som finns inom aktuell verksamhet, finns det möjlighet att anpassa efter andra verksamheter.

Homosocialitetens kraft : hur unga män ”gör” maskulinitet i grupp och individuellt

The power of homosociality: how young men “do” masculinity in groups and individually Using young men’s narratives, about other men, friends, dates and girlfriends, this article discusses the following questions: Can the interpretation – the understanding of young men’s collective presentations of masculinity as a surface that hides a more complex masculinity – undermine how we interpret young men’s talk about and interaction with other men, as well as with women? Can this disassembling understanding have an impact on how young men interpret and relive the interactions with other men, as well as with women? Can this disassembling of the homosocially created masculinity from the more individually created masculinity shape secondary gains for the young men, such as e.g. a more flexible and stretchable arena of responsibility, as well as more flexible space of acting? Thomas Johansson, Professor of Social Work social work, states that if we only focus the homosocially created masculinity, this will reshape a less nuanced picture of young men’s way of doing masculinity (Johansson 2005). Thus, young men’s vulnerability and difficulties remain hidden. However, this disassembling of the homosocially created masculinity from the more individually based doings of masculinity could possibly also give secondary gains, such as e.g. a more flexible and stretchable field of responsibility, as well as more flexible space of acting. This article shows that using a fragmentised and situated masculinity, as a way of understanding the complexity and the ambivalence in young men’s project of doing masculinity, makes evident – on the one hand – the vulnerability in young men’s process of doing masculinity. On the other hand, however, this view also makes it possible for young men to avoid responsibility for their actions. Instead the situated context – e.g. if in a peer group or alone, and what kind of relations the young man has – will be significant for how the act will be interpreted. The empirical material consists of six individual interviews and one group interview with four men. The age span of the participants is 16 to 24 years old. The overall theme for the discussions is heterosexual practice and relations.

Det är enklare i teorin… Om skolutveckling i praktiken : En fallstudie av ett skolutvecklingsprojekt i en gymnasieskola

This dissertation is a case study dealing with a school development project that took place in an upper secondary school as a result of a merger of two schools with different cultures. The project used a method called “Frirumsmodellen” and was planned to be conducted in three steps. The first was to carry out a cultural analysis in order to map the preconditions to start a school development project. The second was to carry out concrete actions and finally study eventual effects from such activities by doing a second cultural analysis. My role was to be a supervisor in the school development work, but at the same time study how this work was conducted and its impact in the ordinary school day. The dissertation takes its departure in the fact that schools are political governed. The mission of schools is never neutral; it is always an expression of behind laying social forces, ideologies and ideals of the contemporary society. Of this reason, there is a close connection between the macro political level and the micro political level. Another point of departure is the transition from a modern to a post modern society that gives the character to the changes that take place in schools. Steering of schools has partly been treated as a technical implementation problem. Schools contain on going conflicts between different interest groups that, more or less regularly, end up in educational reforms. These reforms generate school development activities in the single school. Undoubtedly, this makes school development to a complex process. At a rather late stage of the study I decided not to fulfil my task to follow the original plan. I instead let the school development project as a model to be in focus. The over all purpose was formulated: How is it possible to understand what happened in the school development project in the Falkgymnasiet and why was it not possible to carry it out as it was said in the project plan? To interpret what took place during the project I did create an interpretation frame of implementation and complexity theory that also made it possible to critically scrutinise the “Frirumsmodellen”. Already in an early stage of the process it was obvious that the “Frirumsmodellen” did not supply any tools to use and it became disconnected from the project. The project in it selves was marginalised and made invisible. The headmaster used the situation to change things she thought were important to develop. As a result, things happened, but most of the involved people did not at first hand connect this to the project. It is, of course, difficult in detail to say what caused what. The complexity theory successively made the hidden patterns revealed, hidden unofficial potentates visible, as well as unpredictable conditions that generated reactions from the personnel in front of a development work. Together this was rather efficient obstacles for not changing this school. I also discuss school development and implementation problems on a general level, for example, the possibility to transform a top-down initiated project to be bottom-up driven and using project as a tool for school development work. It was obvious that headmasters and teachers must be prepared to handle the ideological dimensions of problems schools have to face. Consequently, development work is about making problems visible and to handle these in the intersection point between the intentions of educational policies, pedagogical researchers, school administrators, headmasters, teachers and pupils. The ideological dimension also contains an existential issue. Do I as a teacher share the intentions for the development work? If not, how must I act?

Predictive models for chronic renal disease using decision trees, naïve bayes and case-based methods

Data mining can be used in healthcare industry to “mine” clinical data to discover hidden information for intelligent and affective decision making. Discovery of hidden patterns and relationships often goes intact, yet advanced data mining techniques can be helpful as remedy to this scenario. This thesis mainly deals with Intelligent Prediction of Chronic Renal Disease (IPCRD). Data covers blood, urine test, and external symptoms applied to predict chronic renal disease. Data from the database is initially transformed to Weka (3.6) and Chi-Square method is used for features section. After normalizing data, three classifiers were applied and efficiency of output is evaluated. Mainly, three classifiers are analyzed: Decision Tree, Naïve Bayes, K-Nearest Neighbour algorithm. Results show that each technique has its unique strength in realizing the objectives of the defined mining goals. Efficiency of Decision Tree and KNN was almost same but Naïve Bayes proved a comparative edge over others. Further sensitivity and specificity tests are used as statistical measures to examine the performance of a binary classification. Sensitivity (also called recall rate in some fields) measures the proportion of actual positives which are correctly identified while Specificity measures the proportion of negatives which are correctly identified. CRISP-DM methodology is applied to build the mining models. It consists of six major phases: business understanding, data understanding, data preparation, modeling, evaluation, and deployment.