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This essay sets out to theorize the "new" Arctic Ocean as a pivot from which our standard map of the world is currently being reconceptualized. Drawing on theories from the fields of Atlantic and Pacific studies, I argue that the changing Arctic, characterized by melting ice and increased accessibility, must be understood both as a space of transit that connects Atlantic and Pacific worlds in unprecedented ways, and as an oceanic world and contact zone in its own right. I examine both functions of the Arctic via a reading of the dispute over the Northwest Passage (which emphasizes the Arctic as a space of transit) and the contemporary assessment of new models of sovereignty in the Arctic region (which concentrates on the circumpolar Arctic as an oceanic world). However, both of these debates frequently exclude indigenous positions on the Arctic. By reading Canadian Inuit theories on the Arctic alongside the more prominent debates, I argue for a decolonizing reading of the Arctic inspired by Inuit articulations of the "Inuit Sea." In such a reading, Inuit conceptions provide crucial interventions into theorizing the Arctic. They also, in turn, contribute to discussions on indigeneity, sovereignty, and archipelagic theory in Atlantic and Pacific studies.
Background/Aims: Angiogenesis plays a key role during embryonic development. The vascular endothelin (ET) system is involved in the regulation of angiogenesis. Lipopolysaccharides (LPS) could induce angiogenesis. The effects of ET blockers on baseline and LPS-stimulated angiogenesis during embryonic development remain unknown so far. Methods: The blood vessel density (BVD) of chorioallantoic membranes (CAMs), which were treated with saline (control), LPS, and/or BQ123 and the ETB blocker BQ788, were quantified and analyzed using an IPP 6.0 image analysis program. Moreover, the expressions of ET-1, ET-2, ET3, ET receptor A (ETRA), ET receptor B (ETRB) and VEGFR2 mRNA during embryogenesis were analyzed by semi-quantitative RT-PCR. Results: All components of the ET system are detectable during chicken embryogenesis. LPS increased angiogenesis substantially. This process was completely blocked by the treatment of a combination of the ETA receptor blockers-BQ123 and the ETB receptor blocker BQ788. This effect was accompanied by a decrease in ETRA, ETRB, and VEGFR2 gene expression. However, the baseline angiogenesis was not affected by combined ETA/ETB receptor blockade. Conclusion: During chicken embryogenesis, the LPS-stimulated angiogenesis, but not baseline angiogenesis, is sensitive to combined ETA/ETB receptor blockade.
Many educational technology proponents support the Technological Pedagogical Content Knowledge (TPACK) model as a way to conceptualize teaching with technology, but recent TPACK research shows a need for empirical studies regarding the development of this knowledge. This proof-of-concept study applies mixed-methods to investigate the meta-cognitive awareness produced by teachers who participate in the Graphic Assessment of TPACK Instrument (GATI). This process involves creating graphical representations (circles of differing sizes and the degree of their overlap) that represent what teachers understand to be their current and aspired TPACK. This study documented teachers’ explanations during a think-aloud procedure as they created their GATI figures. The in-depth data from two German teachers who participated in the process captured the details of their experience and demonstrated the potential of the GATI to support teachers in reflecting about their professional knowledge and in determining their own professional development activities. These findings will be informative to future pilot studies involving the larger design of the GATI process, to better understand the role of teachers’ meta-conceptual awareness, and to better ascertain how the GATI might be used to support professional development on a larger scale.
This paper analyses the interaction of domestic political elites and external donors against the backdrop of Mozambique’s decentralisation process. The empirical research at national and local levels supports the hypothesis that informal power structures influence the dynamics of this interaction. Consequently, this contributes to an outcome of externally induced democratisation different to what was intended by external actors. The decentralisation process has been utilised by ruling domestic elites for political purposes. Donors have rather focused on the technical side and ignored this informal dimension. By analysing the diverging objectives and perceptions of external and internal actors, as well as the instrumentalisation of formal democratic structures, it becomes clear, that the ‘informal has to be seen as normal’. At a theoretical level, the analysis contributes to elite-oriented approaches of post-conflict democratisation by adding ‘the informal’ as an additional factor for the dynamics of external-internal interaction. At a policy level, external actors need to take more into account informal power structures and their ambivalence for state-building and democratisation.
Involvement of disadvantaged individuals into entrepreneurship facilitates their social integration into mainstream societies. The present study addresses the drivers of social entrepreneurial appraisal among hearing-impaired individuals within a unique social minority environment. In prior research, social appraisal was empirically shown to determine social entrepreneurial intention. Adopting the theory of planned behaviour, this study investigates the impact of entrepreneurial self-efficacy, general social support and perceived barriers on social entrepreneurial appraisal. Based on a survey with 221 respondents, our results demonstrate that social entrepreneurial appraisal of hearing-impaired individuals result from their entrepreneurial self-efficacy and general social support. In terms of taking advantage of social opportunities, importance should be given to the role of entrepreneurial education and heterogeneous networks across minorities.
Background: The association between stature and social dominance is known. Dominance within social groups and current politics are related issues. We therefore aimed to compare estimates of the opinion of a population about their current political issues, with physical growth. Material and methods: We used data on the 2012 and the 2014 elections for the Japanese House of Representatives and the percent proportion of votes of the 47 prefectures of Japan, and regional data on body height of 17.5 year old men and women. Information on capita income, possession of mobile phones, urban/rural population ratio, and age distribution were added to capture socioeconomic factors. Four political parties were present in most of the 47 prefectures: the Liberal Democratic Party (LDP), the Democratic Party of Japan (DPJ), the New Komeito Party (Kom) that is known for their social network community, and the Japanese Communist Party (JCP). Results: A dense network of associations exists between height, age distribution, per capita income, number of smartphones, and voting results. Male and female body height was inversely related with the proportion of votes for New Komeito Party. Average stature decreases by one mm per percent votes for this political party. Medium strong positive associations were found for male body height and voting results of the DPJ and for female body height with the JCP election results. Conclusion: In modern Japan, popular preferences for conservative political structures coincide with shorter stature.
Introduction: Body height is influenced by biological factors such as genetics, nutrition and health, but also by the social network, and environmental and economical factors. During centuries, the Japanese society has developed on islands. This setting provides ideal natural conditions for studying the influence of social networks on human height. Material and methods: We investigated body height of male Japanese students aged 17.5 years obtained in 47 prefectures, from the Japanese school health survey of the years 1955, 1975, 1995, and 2015. Results: Japanese students increased in height from 163.23 cm in 1955 to 170.84 cm in 1995, with no further increase thereafter (170.63 cm in 2015). Students living in neighboring prefectures were similar in height. The correlation of height between neighboring prefectures ranged between r = 0.79 and r = 0.49 among first degree neighbors, between r = 0.49 and r = 0.21 among second degree neighbors and dropped to insignificance among third degree neighbors indicating psychosocial effects of the community on body height. Tall stature and short stature prefectures did not remain tall or short throughout history. Autocorrelations of height within the same prefectures decreased from the 20 years periods of 1955-1975, 1975-1995 and 1995-2015 (r = 0.52, r = 0.61, r = 0.63, respectively) to the 40 years periods of 1955-1995 and 1975-2015 (r = 0.49, r = 0.52), down to the 60 years period of 1955-2015 (r = 0.27), indicating significant volatility of height. Conclusion: Body height of 17.5 years old Japanese students increased since 1955. Body height depended on height of the neighboring prefecture, but was volatile with decreasing autocorrelation during a period of 60 years.
Body height has traditionally been looked upon as a mirror of the condition of society, short height being an indicator of poor nutritional status, poor education, and low social status and income. This view has recently been questioned. We aimed to quantify the effects of nutrition, education, sibship size, and household income, factors that are conventionally considered to be related to child growth, on body height of children and adolescents raised under urban Indian conditions. Sample and methods: We re-analyzed several anthropometric measurements and questionnaires with questions on sibship size, fathers’ and mother’s education, and monthly family expenditure, from two cross-sectional growth studies performed in Kolkata, India. The first Kolkata Growth Study (KG1) took place in 1982-1983, with data on 825 Bengali boys aged 7 to 16 years; and the second Kolkata Growth Study (KG2) between 1999 and 2011 with data of 1999 boys aged 7 to 21 years from Bengali Hindu families, and data of 2195 girls obtained between 2005 and 2011. Results: Indian children showed positive insignificant secular trends in height and a significant secular trend in weight and BMI between between 1982 and 2011. Yet, multiple regression analysis failed to detect an association between nutritional status (expressed in terms of skinfold thickness), monthly family expenditure and sibship size with body height of these children. The analysis only revealed an influence of parental education on female, but not on male height. Conclusion: We failed to detect influences of nutrition, sibship size, and monthly family expenditure on body height in a large sample of children and adolescents raised in Kolkata, India, between 1982 and 2011. We found a mild positive association between parental education and girls’ height. The data question current concepts regarding the impact of nutrition, and household and economic factors on growth, but instead underscore the effect of parental education.
Background: In our modern world, the way of life in nutritional and activity behaviour has changed. As a consequence, parallel trends of an epidemic of overweight and a decline in external skeletal robusticity are observed in children and adolescents. Aim: We aim to develop reference centiles for external skeletal robusticity of European girls and boys aged 0 to 18 years using the Frame Index as an indicator and identify population specific age-related patterns. Methods: We analysed cross-sectional & longitudinal data on body height and elbow breadth of boys and girls from Europe (0-18 years, n = 41.679), India (7-18 years, n = 3.297) and South Africa (3-18 years, n = 4.346). As an indicator of external skeletal robusticity Frame Index after Frisancho (1990) was used. We developed centiles for boys and girls using the LMS-method and its extension. Results: Boys have greater external skeletal robusticity than girls. Whereas in girls Frame Index decreases continuously during growth, an increase of Frame Index from 12 to 16 years in European boys can be observed. Indian and South African boys are almost similar in Frame Index to European boys. In girls, the pattern is slightly different. Whereas South African girls are similar to European girls, Indian girls show a lesser external skeletal robusticity. Conclusion: Accurate references for external skeletal robusticity are needed to evaluate if skeletal development is adequate per age. They should be used to monitor effects of changes in way of life and physical activity levels in children and adolescents to avoid negative health outcomes like osteoporosis and arthrosis.
As tall as my peers
(2018)
Background: We define migrants as people who move from their place of birth to a new place of residence. Migration usually is directed by "Push-Pull" factors, for example to escape from poor living conditions or to find more prosperous socio-economic conditions. Migrant children tend to assimilate quickly, and soon perceive themselves as peers within their new social networks. Differences exist between growth of first generation and second generation migrants. Methods: We review body heights and height distributions of historic and modern migrant populations to test two hypotheses: 1) that migrant and adopted children coming from lower social status localities to higher status localities adjust their height growth toward the mean of the dominant recipient social network, and 2) social dominant colonial and military migrants display growth that significantly surpasses the median height of both the conquered population and the population of origin. Our analytical framework also considered social networks. Recent publications indicate that spatial connectedness (community effects) and social competitiveness can affect human growth. Results: Migrant children and adolescents of lower social status rapidly adjust in height towards average height of their hosts, but tend to mature earlier, and are prone to overweight. The mean height of colonial/military migrants does surpass that of the conquered and origin population. Conclusion: Observations on human social networks, non-human animal strategic growth adjustments, and competitive growth processes strengthen the concept of social connectedness being involved in the regulation of human migrant growth.
Because of political conflicts and climate change, migration will be increased worldwide and integration in host societies is a challenge also for migrants. We hypothesize that migrants, who take up the challenge in a new social environment are taller than migrants who do not pose this challenge. We analyze by a questionnaire possible social, nutritional and ethnic influencing factors to body height (BH) of adult offspring of Turkish migrants (n = 82, 39 males) aged from 18 to 34 years (mean age 24.6 years). The results of multiple regression (downward selection) show that the more a male adult offspring of Turkish migrants feels like belonging to the Turkish culture, the smaller he is (95% CI, -3.79, -0.323). Further, the more a male adult offspring of Turkish migrants feels like belonging to the German culture, the taller he is (95% CI, -0.152, 1.738). We discussed it comparable to primates taking up their challenge in dominance, where as a result their body size increase is associated with higher IGF-1 level. IGF-1 is associated with emotional belonging and has a fundamental role in the regulation of metabolism and growth of the human body. With all pilot characteristics of our study results show that the successful challenge of integration in a new society is strongly associated with the emotional integration and identification in the sense of a personal sense of belonging to society. We discuss taller BH as a signal of social growth adjustment. In this sense, a secular trend of BH adaptation of migrants to hosts is a sign of integration.
Lipid-soluble arsenicals, so-called arsenolipids, have gained a lot of attention in the last few years because of their presence in many seafoods and reports showing substantial cytotoxicity emanating from arsenic-containing hydrocarbons (AsHCs), a prominent subgroup of the arsenolipids. More recent in vivo and in vitro studies indicate that some arsenolipids might have adverse effects on brain health. In the present study, we focused on the effects of selected arsenolipids and three representative metabolites on the blood-cerebrospinal fluid barrier (B-CSF-B), a brain-regulating interface. For this purpose, we incubated an in vitro model of the B-CSF-B composed of porcine choroid plexus epithelial cells (PCPECs) with three AsHCs, two arsenic-containing fatty acids (AsFAs) and three representative arsenolipid metabolites (dimethylarsinic acid, thio/oxo-dimethylpropanoic acid) to examine their cytotoxic potential and impact on barrier integrity. The toxic arsenic species arsenite was also tested in this way and served as a reference substance. While AsFAs and the metabolites showed no cytotoxic effects in the conducted assays, AsHCs showed a strong cytotoxicity, being up to 1.5-fold more cytotoxic than arsenite. Analysis of the in vitro B-CSF-B integrity showed a concentration dependent disruption of the barrier within 72 h. The correlation with the decreased plasma membrane surface area (measured as capacitance) indicates cytotoxic effects. These findings suggest exposure to elevated levels of certain arsenolipids may have detrimental consequences for the central nervous system.
Multi-element determination in human samples is very challenging. Especially in human intervention studies sample volumes are often limited to a few microliters and due to the high number of samples a high-throughput is indispensable. Here, we present a state-of-the-art ICP-MS/MS-based method for the analysis of essential (trace) elements, namely Mg, Ca, Fe, Cu, Zn, Mo, Se and I, as well as food-relevant toxic elements such as As and Cd. The developed method was validated regarding linearity of the calibration curves, method LODs and LOQs, selectivity and trueness as well as precision. The established reliable method was applied to quantify the element serum concentrations of participants of a human intervention study (LeguAN). The participants received isocaloric diets, either rich in plant protein or in animal protein. While the serum concentrations of Mg and Mo increased in participants receiving the plant protein-based diet (above all legumes), the Se concentration in serum decreased. In contrast, the animal protein-based diet, rich in meat and dairy products, resulted in an increased Se concentration in serum.
Obwohl argumentative Kompetenzen in den Bildungsstandards einen hohen Stellenwert einnehmen, existiert nach wie vor eine eher geringe Anzahl empirischer Untersuchungen zur Entwicklung argumentativer Fähigkeiten von Schülerinnen und Schülern. Dieser Umstand wird weniger durch einen Mangel an argumentationstheoretischen Modellen verursacht als vielmehr von einer Reihe theoretischer Probleme, die insbesondere darin liegen, dass alltagsweltliche Argumentationen sprachliche Vagheiten und strukturelle Unvollständigkeiten aufweisen, die eine disjunkte empirische Kategorisierung erschweren. Im Beitrag wird ein Analysemodell vorgestellt, das diese Probleme teils löst, teils theoretisch umgeht und so die Grundlagen für eine reliable Datenerhebung bildet. Die Funktionsfähigkeit und didaktische Aussagekraft des Modells wird im Anschluss anhand eines Korpus mit argumentativen Gesprächsbeiträgen von Schülerinnen und Schülern der 8. und 10. Jahrgangsstufe demonstriert, bei der verschiedene Altersunterschiede sowie unterschiedliche argumentative Stile belegt werden können.
Ein Werk zweier Künstler?
(2018)
The author suggests an attribution for two largely unknown Baroque sculptures inside the Church of St. Peter and Paul at Potsdam. The crucifixus, which has so far not been attributed to an artist, is shown to exhibit parallels to a 1716 work by Paul Egell. It remains unclear, however, whether the Potsdam crucifixus was also created by Egell himself or by Johann Peter Benckert, who congenially completed it in 1763 with a statue of the kneeling Maria Magdalena. The appealing depiction of the saint as an elegant sinner and penitent offers believers various possibilities for identification.
Learning analytics design
(2018)
Instructional designers use learning analytics information to evaluate designs of learning environments, learning materials, and tasks, and adjust difficulty levels, as well as measure the impact of interventions and feedback. Integrating real-time educational data and analysis into the design of learning environments, referred to as learning analytics design (LAD), seems to be a promising approach. Valid pedagogical recommendations may be suggested on the fly as learning analytics methodologies and visualizations evolve and as reliable tools become available and ready for classroom practice. This chapter aims to offer an overview on design and analytics of learning environments before reviewing opportunities of learning analytics design for optimizing learning environments in near real time. Learning analytics (LA) use static and dynamic information about learners and learning environments—assessing, eliciting, and analyzing them—for real-time modeling, prediction, and optimization of learning processes, learning environments, and educational decision-making.
Conservation nongovernmental organisations (NGOs) are often involved in the design and implementation of global forest management initiatives such as the REDD+, which currently is being rolled out by the UNFCCC, the UN-REDD Programme and the World Bank as part of efforts to mitigate climate change. Nigeria joined the UN-REDD in 2010 and submitted its REDD+ readiness proposal in 2011. The proposal has a national component and subnational forestry activities in the Cross River State (CRS) as the pilot site. This chapter examines the involvement of local NGOs in the CRS consultative participatory meetings to validate the Nigeria-REDD proposal. It shows that political representation of local communities in the validation exercise was through customary authorities and NGOs who claim to speak for and are recognised as advocates for the communities. Local government authorities, the substantive political representatives of local communities were left out of the process. The chapter also shows how the CRS Forestry Commission, which organised the validation exercise, used NGOs as pawns to legitimise it, and how these NGOs were powerless to challenge the Forestry Commission. In contrast, local governments, the third tier of government and political authority routinely disrespected by state-level administrators, regularly challenge such higher level government actors in the courts and the national legislature. Thus, local NGOs may speak and work for local social development but compared to the substantive political representatives at the local level (e.g., local government authorities), local NGOs have limited resources to challenge the political shenanigans of the state.
Remote sensing, which is a common method to examine land-use/land-cover (LULC) changes, could be useful in the analysis of livestock ecosystem transformations. In the last two decades, before Landsat images were free, developing countries could not afford monitoring through remote sensing because of the high cost of acquiring satellite imagery and commercial software. However, Landsat time series nowadays allows the characterization of changes in vegetation across large areas over time. The aim of this study is to analyse the LULC changes affecting forest frontiers and traditional silvopastoral systems (TSPS) in a representative livestock area of Nicaragua. Nearly cloud-free Landsat scenes - a Landsat 5 Thematic Mapper (TM) scene from 1986 and a Landsat 8 Operational Land Imager (OLI) scene from 2015 - have been the data sets used in the study. A process chain following a four-step definition of the remote-sensing process was conceptually developed and implemented based onfree open source software components and by applying the random forest (RF) algorithm. A conceptual LULC classification scheme representing TSPS was developed. Although the imagery shows a heterogeneous surface cover and mixed pixels, it is possible to achieve promising classification results with the RF algorithm with out-of-the-bag (OOB) errors below 13% for both images along with an overall accuracy level of 85.9% for the 2015 subset and 85.2% for the 1986 subset. The classification shows that from 1986 to 2015 (29years) the intervened secondary forest (ISF) increased 2.6 times, whereas the degraded pastures decreased by 34.5%. The livestock landscape in Matiguas is in a state of constant transformation, but the main changes head towards the positive direction of tree-cover recovery and an increased number of areas of natural regeneration.
Александр фон Гумбольдт
(2018)
Научные интересы А. фон Гумбольдта протираются от антропологии и доколумбовой истории Америки до геологии и географии, климатологии и теории культуры; от физики и географии растений до истории языка, вулканологии и зоологии. Будучи ученым, он пересекал дисциплинарные границы и искал новые пути познания. Гумбольдт развивал трансдисциплинарное и, в широком смысле, номадическое знание. Как настоящий кочевник, он не стремился завоевать или разрушить территорию знания. И потому неудивительно, что он стал одним из основоположников экологического и гео-экологического мышления. Гумбольдт публиковал работы на немецком и французском языках. В своих «Американских дневниках», которые были возвращены в Берлин в ноябре 2013 г., но до сих пор не изучены, Гумбольдт постоянно переходит с немецкого на французский, с латинского на испанский. Автор «Космоса» чужд всякого национализма. Гумбольдт – это номад от науки, и в этом смысле – гражданин мира. Первый теоретик глобализации кочевал от слова к слову, от науки к науке, от мира к миру. Для него постоянное перемещение было не просто основой научной программы, а образом жизни. Гумбольдт не стремился к специализации в знании, поскольку она ограничивает диалог с другими областями. Его мышление не укладывается в привычные понятия дисциплинарности или междисциплинарности. Оно взыскует нового мира, в котором человечество будет существовать в согласии и свободе.