On the influence of climatic factors on the ratio between the cosmogenic isotope 14C and total carbon in the atmosphere in the past

Radiocarbon ¹⁴C is a cosmogenic isotope, which is most extensively used by scientists from a wide variety of fields. Its rate of generation in the atmosphere depends on solar modulation and thus, studying ¹⁴C concentration in natural archives, one can reconstruct solar activity level in the past. The paper shows results of box-model calculations of generation of the ¹⁴C isotope in the atmosphere and its relative abundance during the time interval 1389–1800 AD, taking into account influence of changing climate. This interval includes the deep minimum of solar activity and period of significant change in atmospheric concentration of CO₂ and global temperature. The performed analysis showed that concentration of ¹⁴C in the atmosphere reflects not only variations of the galactic cosmic rays intensity but as well changes of temperature and atmospheric CO₂ concentration. It is shown that the decrease in CO₂ concentration in the atmosphere during 1550–1600 can be connected with absorption of CO₂ by the ocean surface layer. Thus, taking into account the climatic changes is an important condition for the reconstruction of solar activity in the past using data based on cosmogenic isotopes.     

Performing the global through the local—globalisation and individualisation in the spatial practices of young East Germans

This paper aims to show how young people in former East Germany respond to the globalising processes that are part of the transformation of their society from a state-socialist to a capitalist one. It focuses particularly on the differential ways in which young people perform their identities as global/local subjects through the uses that they make of urban space. While emphasising the agency of young people, the paper seeks to examine the dialectic between globalising forces that are largely beyond their control and the negotiation of these forces in everyday practices of identity-formation. Conceptually, the paper draws particularly on the work of Beck (2000) Beck, U. 2000. “What is Globalization?”. Cambridge and Oxford: Polity Press.  [Google Scholar], Beck and Gernsheim (2002) Beck, U. and Beck-Gernsheim, E. 2002. Individualization. Institutionalized Individualism and its Social and Political Consequences, London: Sage.  [Google Scholar] and Giddens (1994) Giddens, A. 1994. Modernity and Self-Identity. Self and Society in the Late Modern Age, Cambridge: Polity Press.  [Google Scholar] in order to conceptualise the connections between globalisation and individualisation, as well as on feminist and recent geographical work on performativity (Butler, 1990 Butler, J. 1990. Gender Trouble. Feminism and the Subversion of Identity, London and New York: Routledge.  [Google Scholar], 1993 Butler, J. 1993. Bodies that Matter. On the Discursive Limits of ‘Sex’, London and New York: Routledge.  [Google Scholar]; Rose, 1996 Rose, G. 1996. “As if the mirrors had bled: masculine dwelling, masculine theory and feminist masquerades”. In BodySpace: Destabilising Geographies of Gender and Sexuality, Edited by: Duncan, N. 56–74. London and New York: Routledge.  [Google Scholar]; Gregson and Rose, 2000 Gregson, N. and Rose, G. 2000. ‘Taking Butler elsewhere: performativities, spatialities and subjectivities’. Environment and Planning D: Society and Space, 18(4): 433–452. [Crossref], [Web of Science ®] [Google Scholar]; Thrift, 1996 Thrift, N. 1996. Spatial Formations, London: Sage.  [Google Scholar]; Dewsbury, 2000 Dewsbury, J.-D. 2000. ‘Performativity and the event: enacting a philosophy of difference’. Environment and Planning D: Society and Space, 18(4): 473–496. [Crossref], [Web of Science ®] [Google Scholar]; Dewsbury and Naylor, 2002 Dewsbury, J.-D. and Naylor, S. 2002. Practicing geographical knowledge: fields, bodies and dissemination. Area, 34(3): 253–260.  [Google Scholar]) in order to gain an embodied understanding of the ways in which individuals construct themselves as global/local subjects.     

Selbstständigkeit als Berufsalternative?!

Ohne Zusammenfassung     

Problems and pitfalls in the diagnosis of linear enamel hypoplasia in cheek teeth of cattle

Prevalence and intensity of enamel hypoplasia have been used as markers of generalized physiological stress during dental development in a wide range of mammalian taxa. We studied cattle (Bos taurus) cheek teeth exhibiting morphological characteristics that are of relevance to the diagnosis of enamel hypoplasia in this and other bovid species. These characteristics were multiple, more or less horizontally arranged (waveform) lines or grooves in the cementum of the tooth crown and the adjacent root area, leading to an imbricated appearance of the cementum. On macroscopic examination of tooth surfaces, these lines resembled linear enamel hypoplasia (LEH). Microscopic analysis of tooth sections, however, revealed that the lines occurred in the cementum only, and that the underlying enamel did not exhibit morphological irregularities. In cheek teeth of older cattle, a thick cementum layer is regularly found in the cervical crown portion and the adjacent root area. Apposition of this cementum is related to the uplifting of the teeth from their alveoli, a process that compensates for the shortening of the tooth crowns due to occlusal wear. In the studied specimens, a pronounced periodic nature of tooth uplifting and the related deposition of cementum is the likely cause for the observed imbricated appearance of the cementum. While this phenomenon may be misinterpreted as representing a case of LEH, presence of enamel hypoplasia in bovid teeth may be overlooked when the defects become filled with coronal cementum and are therefore not apparent on external inspection. This was the case in one of the cattle teeth analyzed by us, in which the hypoplastic enamel defects were, however, clearly discernible in ground sections. Microscopic analysis of tooth sections is recommended for recording of LEH in bovid teeth in cases where macroscopic examination of tooth surfaces alone does not produce unequivocal results.     

Proximity,trust and morality in networks

Network interaction is embedded in social settings, which allows for the development of trust. Trust is supposed to be an efficient functional equivalent of contracts, guarantees, insurances, safeguards, etc. Trust between actors reduces transaction costs. However, trust cannot be introduced and enforced within interaction relationships. It is argued that trust is more likely to occur and to be prevalent when actors have the spatial capability for personal, direct interaction. Thus, proximity and trust are supposed to be positively related to each other. Proximity is strongly interrelated with embeddedness. In the discussion about morality in organisations, there is an assumption we referred to as the 'moral spill-over effect': it is impossible, it is said, to restrict moral competencies and moral behaviour to one particular situation, environment, or topic. However, we argue that, even though trust is a term that is described in moral theory, trust and morality are not necessarily positively correlated. This means that even if embeddedness and proximity in a network lead to an increase of trust between network partners, it does not necessarily produce moral spill-over effects. Thus, proximity and morality do not necessarily have to be positively correlated with each other. The influence of proximity on morality can be positive or negative, depending on the social surrounding in which network collaboration is embedded.     

Hochschulausbildung und Consultingpraxis

Die Consultingbranche bietet für Geographinnen und Geographen ein breites und interessantes Betätigungsfeld. Dieses Berufsfeld kann bereits durch universitäre Veranstaltungen für Studierende erschlossen werden. Um Einblicke in das Tätigkeitsfeld, die Anforderungen und Qualifikationsprofile eines Beraters zu geben, bieten sich Projektseminare an, die in Kooperation mit der Hochschule und Berufspraktikern durchgeführt werden.     

Papier oder Online?

Am Beispiel einer touristischen Image- bzw. Marktuntersuchung besch?ftigt sich der vorliegende Aufsatz mit den M?glichkeiten zur internet-basierten Datenerhebung im Rahmen empirischer Forschungsprojekte. Die Ergebnisse einer auf einer Zufallsauswahl basierenden schriftlichen Befragung mit Postversand und einer Befragung im Internet werden hierzu miteinander verglichen und ihre Eignung für die gew?hlte Zielsetzung bewertet. Die Darstellung erfolgt anhand des konkreten Fallbeispiels des Projektes „Stuttgart Regio: Touristische Infrastruktur- und Marketing-Analyse.”