@inproceedings{NeumannSchaalMesserschmidtGrenzetal.2012, author = {Neumann-Schaal, M. and Messerschmidt, Katrin and Grenz, N. and Micheel, Burkhard and Heilmann, K.}, title = {Use of antibody gene library for the isolation of specific single chain antibodies by ampicillin-antigen conjugates}, series = {Immunology : an official journal of the British Society for Immunology}, volume = {137}, booktitle = {Immunology : an official journal of the British Society for Immunology}, number = {3}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0019-2805}, pages = {661 -- 661}, year = {2012}, language = {en} } @article{BangHoviSprinz2012, author = {Bang, Guri and Hovi, Jon and Sprinz, Detlef F.}, title = {US presidents and the failure to ratify multilateral environmental agreements}, series = {Climate policy}, volume = {12}, journal = {Climate policy}, number = {6}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1469-3062}, doi = {10.1080/14693062.2012.699788}, pages = {755 -- 763}, year = {2012}, abstract = {Whereas the US President signed the Kyoto Protocol, the failure of the US Congress to ratify it seriously hampered subsequent international climate cooperation. This recent US trend, of signing environmental treaties but failing to ratify them, could thwart attempts to come to a future climate agreement. Two complementary explanations of this trend are proposed. First, the political system of the US has distinct institutional features that make it difficult for presidents to predict whether the Senate will give its advice and consent to multilateral environmental agreements (MEAs) and whether Congress will pass the required enabling legislation. Second, elected for a fixed term, US presidents might benefit politically from supporting MEAs even when knowing that legislative support is not forthcoming. Four policy implications are explored, concerning the scope for unilateral presidential action, the potential for bipartisan congressional support, the effectiveness of a treaty without the US, and the prospects for a deep, new climate treaty. Policy relevance Why does the failure of US ratification of multilateral environmental treaties occur? This article analyses the domestic political mechanisms involved in cases of failed US ratification. US non-participation in global environmental institutions often has serious ramifications. For example, it sharply limited Kyoto's effectiveness and seriously hampered international climate negotiations for years. Although at COP 17 in Durban the parties agreed to negotiate a new agreement by 2015, a new global climate treaty may well trigger a situation resembling the one President Clinton faced in 1997 when he signed Kyoto but never obtained support for it in the Senate. US failure to ratify could thwart future climate agreements.}, language = {en} } @article{KirpichenkoShainyanKleinpeter2012, author = {Kirpichenko, Svetlana V. and Shainyan, Bagrat A. and Kleinpeter, Erich}, title = {Unusual conformational preferences of 1,3-dimethyl-3-isopropoxy-3-silapiperidine}, series = {Journal of physical organic chemistry}, volume = {25}, journal = {Journal of physical organic chemistry}, number = {12}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0894-3230}, doi = {10.1002/poc.3028}, pages = {1321 -- 1327}, year = {2012}, abstract = {The conformational analysis of the first representative of the Si-alkoxy substituted six-membered Si,N-heterocycles, 1,3-dimethyl-3-isopropoxy-3-silapiperidine, was performed by low-temperature 1H and 13C NMR spectroscopy and DFT theoretical calculations. In contrast to the expectations from the conformational energies of methyl and alkoxy substituents, the Meaxi-PrOeq conformer was found to predominate in the conformational equilibrium in the ratio Meaxi-PrOeq : Meeqi-PrOax of ca. 2 : 1 as from the 1H and 13C NMR study. The thermodynamic parameters obtained by the complete line shape analysis showed that the main contribution to the barrier to ring inversion originates from the entropy term of the free energy of activation.}, language = {en} } @article{KeehnerFischer2012, author = {Keehner, Madeleine and Fischer, Martin H.}, title = {Unusual bodies, uncommon behaviors individual and group differences in embodied cognition in spatial tasks}, series = {Spatial cognition and computation}, volume = {12}, journal = {Spatial cognition and computation}, number = {2-3}, publisher = {Taylor \& Francis Group}, address = {Philadelphia}, issn = {1387-5868}, doi = {10.1080/13875868.2012.659303}, pages = {71 -- 82}, year = {2012}, abstract = {This editorial introduces a set of papers on differential embodiment in spatial tasks. According to the theoretical notion of embodied cognition, our experiences of acting in the world, and the constraints of our sensory and motor systems, strongly shape our cognitive functions. In the current set of papers, the authors were asked to particularly consider idiosyncratic or differential embodied cognition in the context of spatial tasks and processes. In each contribution, differential embodiment is considered from one of two complementary perspectives: either by considering unusual individuals, who have atypical bodies or uncommon experiences of interacting with the world; or by exploring individual differences in the general population that reflect the naturally occurring variability in embodied processes. Our editorial summarizes the contributions to this special issue and discusses the insights they offer. We conclude from this collection of papers that exploring differences in the recruitment and involvement of embodied processes can be highly informative, and can add an extra dimension to our understanding of spatial cognitive functions. Taking a broader perspective, it can also shed light on important theoretical and empirical questions concerning the nature of embodied cognition per se.}, language = {en} } @phdthesis{MatallanaRamirez2012, author = {Matallana-Ram{\´i}rez, Lilian Paola}, title = {Unraveling the ORE1 regulon in Arabidopsis thaliana : molecular and functional characterization of up- and down-stream components}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-62646}, school = {Universit{\"a}t Potsdam}, year = {2012}, abstract = {Leaf senescence is an active process required for plant survival, and it is flexibly controlled, allowing plant adaptation to environmental conditions. Although senescence is largely an age-dependent process, it can be triggered by environmental signals and stresses. Leaf senescence coordinates the breakdown and turnover of many cellular components, allowing a massive remobilization and recycling of nutrients from senescing tissues to other organs (e.g., young leaves, roots, and seeds), thus enhancing the fitness of the plant. Such metabolic coordination requires a tight regulation of gene expression. One important mechanism for the regulation of gene expression is at the transcriptional level via transcription factors (TFs). The NAC TF family (NAM, ATAF, CUC) includes various members that show elevated expression during senescence, including ORE1 (ANAC092/AtNAC2) among others. ORE1 was first reported in a screen for mutants with delayed senescence (oresara1, 2, 3, and 11). It was named after the Korean word "oresara," meaning "long-living," and abbreviated to ORE1, 2, 3, and 11, respectively. Although the pivotal role of ORE1 in controlling leaf senescence has recently been demonstrated, the underlying molecular mechanisms and the pathways it regulates are still poorly understood. To unravel the signaling cascade through which ORE1 exerts its function, we analyzed particular features of regulatory pathways up-stream and down-stream of ORE1. We identified characteristic spatial and temporal expression patterns of ORE1 that are conserved in Arabidopsis thaliana and Nicotiana tabacum and that link ORE1 expression to senescence as well as to salt stress. We proved that ORE1 positively regulates natural and dark-induced senescence. Molecular characterization of the ORE1 promoter in silico and experimentally suggested a role of the 5'UTR in mediating ORE1 expression. ORE1 is a putative substrate of a calcium-dependent protein kinase named CKOR (unpublished data). Promising data revealed a positive regulation of putative ORE1 targets by CKOR, suggesting the phosphorylation of ORE1 as a requirement for its regulation. Additionally, as part of the ORE1 up-stream regulatory pathway, we identified the NAC TF ATAF1 which was able to transactivate the ORE1 promoter in vivo. Expression studies using chemically inducible ORE1 overexpression lines and transactivation assays employing leaf mesophyll cell protoplasts provided information on target genes whose expression was rapidly induced upon ORE1 induction. First, a set of target genes was established and referred to as early responding in the ORE1 regulatory network. The consensus binding site (BS) of ORE1 was characterized. Analysis of some putative targets revealed the presence of ORE1 BSs in their promoters and the in vitro and in vivo binding of ORE1 to their promoters. Among these putative target genes, BIFUNCTIONAL NUCLEASE I (BFN1) and VND-Interacting2 (VNI2) were further characterized. The expression of BFN1 was found to be dependent on the presence of ORE1. Our results provide convincing data which support a role for BFN1 as a direct target of ORE1. Characterization of VNI2 in age-dependent and stress-induced senescence revealed ORE1 as a key up-stream regulator since it can bind and activate VNI2 expression in vivo and in vitro. Furthermore, VNI2 was able to promote or delay senescence depending on the presence of an activation domain located in its C-terminal region. The plasticity of this gene might include alternative splicing (AS) to regulate its function in different organs and at different developmental stages, particularly during senescence. A model is proposed on the molecular mechanism governing the dual role of VNI2 during senescence.}, language = {en} } @article{GuljamowDelissenBaumannetal.2012, author = {Guljamow, Arthur and Delissen, Friedmar and Baumann, Otto and Thuenemann, Andreas F. and Dittmann-Th{\"u}nemann, Elke}, title = {Unique properties of eukaryote-type actin and profilin horizontally transferred to cyanobacteria}, series = {PLoS one}, volume = {7}, journal = {PLoS one}, number = {1}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0029926}, pages = {221 -- 231}, year = {2012}, abstract = {A eukaryote-type actin and its binding protein profilin encoded on a genomic island in the cyanobacterium Microcystis aeruginosa PCC 7806 co-localize to form a hollow, spherical enclosure occupying a considerable intracellular space as shown by in vivo fluorescence microscopy. Biochemical and biophysical characterization reveals key differences between these proteins and their eukaryotic homologs. Small-angle X-ray scattering shows that the actin assembles into elongated, filamentous polymers which can be visualized microscopically with fluorescent phalloidin. Whereas rabbit actin forms thin cylindrical filaments about 100 mu m in length, cyanobacterial actin polymers resemble a ribbon, arrest polymerization at 510 lam and tend to form irregular multi-strand assemblies. While eukaryotic profilin is a specific actin monomer binding protein, cyanobacterial profilin shows the unprecedented property of decorating actin filaments. Electron micrographs show that cyanobacterial profilin stimulates actin filament bundling and stabilizes their lateral alignment into heteropolymeric sheets from which the observed hollow enclosure may be formed. We hypothesize that adaptation to the confined space of a bacterial cell devoid of binding proteins usually regulating actin polymerization in eukaryotes has driven the co-evolution of cyanobacterial actin and profilin, giving rise to an intracellular entity.}, language = {en} } @phdthesis{Kuenn2012, author = {K{\"u}nn, Steffen}, title = {Unemployment and active labor market policy : new evidence on start-up subsidies, marginal employment and programs for youth unemployed}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-62718}, school = {Universit{\"a}t Potsdam}, year = {2012}, abstract = {In industrialized economies such as the European countries unemployment rates are very responsive to the business cycle and significant shares stay unemployed for more than one year. To fight cyclical and long-term unemployment countries spend significant shares of their budget on Active Labor Market Policies (ALMP). To improve the allocation and design of ALMP it is essential for policy makers to have reliable evidence on the effectiveness of such programs available. Although the number of studies has been increased during the last decades, policy makers still lack evidence on innovative programs and for specific subgroups of the labor market. Using Germany as a case study, the dissertation aims at contributing in this way by providing new evidence on start-up subsidies, marginal employment and programs for youth unemployed. The idea behind start-up subsidies is to encourage unemployed individuals to exit unemployment by starting their own business. Those programs have compared to traditional programs of ALMP the advantage that not only the participant escapes unemployment but also might generate additional jobs for other individuals. Considering two distinct start-up subsidy programs, the dissertation adds three substantial aspects to the literature: First, the programs are effective in improving the employment and income situation of participants compared to non-participants in the long-run. Second, the analysis on effect heterogeneity reveals that the programs are particularly effective for disadvantaged groups in the labor market like low educated or low qualified individuals, and in regions with unfavorable economic conditions. Third, the analysis considers the effectiveness of start-up programs for women. Due to higher preferences for flexible working hours and limited part-time jobs, unemployed women often face more difficulties to integrate in dependent employment. It can be shown that start-up subsidy programs are very promising as unemployed women become self-employed which gives them more flexibility to reconcile work and family. Overall, the results suggest that the promotion of self-employment among the unemployed is a sensible strategy to fight unemployment by abolishing labor market barriers for disadvantaged groups and sustainably integrating those into the labor market. The next chapter of the dissertation considers the impact of marginal employment on labor market outcomes of the unemployed. Unemployed individuals in Germany are allowed to earn additional income during unemployment without suffering a reduction in their unemployment benefits. Those additional earnings are usually earned by taking up so-called marginal employment that is employment below a certain income level subject to reduced payroll taxes (also known as "mini-job"). The dissertation provides an empirical evaluation of the impact of marginal employment on unemployment duration and subsequent job quality. The results suggest that being marginal employed during unemployment has no significant effect on unemployment duration but extends employment duration. Moreover, it can be shown that taking up marginal employment is particularly effective for long-term unemployed, leading to higher job-finding probabilities and stronger job stability. It seems that mini-jobs can be an effective instrument to help long-term unemployed individuals to find (stable) jobs which is particularly interesting given the persistently high shares of long-term unemployed in European countries. Finally, the dissertation provides an empirical evaluation of the effectiveness of ALMP programs to improve labor market prospects of unemployed youth. Youth are generally considered a population at risk as they have lower search skills and little work experience compared to adults. This results in above-average turnover rates between jobs and unemployment for youth which is particularly sensitive to economic fluctuations. Therefore, countries spend significant resources on ALMP programs to fight youth unemployment. However, so far only little is known about the effectiveness of ALMP for unemployed youth and with respect to Germany no comprehensive quantitative analysis exists at all. Considering seven different ALMP programs, the results show an overall positive picture with respect to post-treatment employment probabilities for all measures under scrutiny except for job creation schemes. With respect to effect heterogeneity, it can be shown that almost all programs particularly improve the labor market prospects of youths with high levels of pretreatment schooling. Furthermore, youths who are assigned to the most successful employment measures have much better characteristics in terms of their pre-treatment employment chances compared to non-participants. Therefore, the program assignment process seems to favor individuals for whom the measures are most beneficial, indicating a lack of ALMP alternatives that could benefit low-educated youths.}, language = {en} } @book{AlbrechtNaumann2012, author = {Albrecht, Alexander and Naumann, Felix}, title = {Understanding cryptic schemata in large extract-transform-load systems}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-201-8}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-61257}, publisher = {Universit{\"a}t Potsdam}, pages = {19}, year = {2012}, abstract = {Extract-Transform-Load (ETL) tools are used for the creation, maintenance, and evolution of data warehouses, data marts, and operational data stores. ETL workflows populate those systems with data from various data sources by specifying and executing a DAG of transformations. Over time, hundreds of individual workflows evolve as new sources and new requirements are integrated into the system. The maintenance and evolution of large-scale ETL systems requires much time and manual effort. A key problem is to understand the meaning of unfamiliar attribute labels in source and target databases and ETL transformations. Hard-to-understand attribute labels lead to frustration and time spent to develop and understand ETL workflows. We present a schema decryption technique to support ETL developers in understanding cryptic schemata of sources, targets, and ETL transformations. For a given ETL system, our recommender-like approach leverages the large number of mapped attribute labels in existing ETL workflows to produce good and meaningful decryptions. In this way we are able to decrypt attribute labels consisting of a number of unfamiliar few-letter abbreviations, such as UNP_PEN_INT, which we can decrypt to UNPAID_PENALTY_INTEREST. We evaluate our schema decryption approach on three real-world repositories of ETL workflows and show that our approach is able to suggest high-quality decryptions for cryptic attribute labels in a given schema.}, language = {en} } @phdthesis{Bross2012, author = {Broß, Justus F. M.}, title = {Understanding and leveraging the social physics of the blogosphere}, address = {Potsdam}, pages = {200 S.}, year = {2012}, language = {en} } @article{ZurellGrimmRossmanithetal.2012, author = {Zurell, Damaris and Grimm, Volker and Rossmanith, Eva and Zbinden, Niklaus and Zimmermann, Niklaus E. and Schr{\"o}der-Esselbach, Boris}, title = {Uncertainty in predictions of range dynamics black grouse climbing the Swiss Alps}, series = {Ecography : pattern and diversity in ecology ; research papers forum}, volume = {35}, journal = {Ecography : pattern and diversity in ecology ; research papers forum}, number = {7}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0906-7590}, doi = {10.1111/j.1600-0587.2011.07200.x}, pages = {590 -- 603}, year = {2012}, abstract = {Empirical species distribution models (SDMs) constitute often the tool of choice for the assessment of rapid climate change effects on species vulnerability. Conclusions regarding extinction risks might be misleading, however, because SDMs do not explicitly incorporate dispersal or other demographic processes. Here, we supplement SDMs with a dynamic population model 1) to predict climate-induced range dynamics for black grouse in Switzerland, 2) to compare direct and indirect measures of extinction risks, and 3) to quantify uncertainty in predictions as well as the sources of that uncertainty. To this end, we linked models of habitat suitability to a spatially explicit, individual-based model. In an extensive sensitivity analysis, we quantified uncertainty in various model outputs introduced by different SDM algorithms, by different climate scenarios and by demographic model parameters. Potentially suitable habitats were predicted to shift uphill and eastwards. By the end of the 21st century, abrupt habitat losses were predicted in the western Prealps for some climate scenarios. In contrast, population size and occupied area were primarily controlled by currently negative population growth and gradually declined from the beginning of the century across all climate scenarios and SDM algorithms. However, predictions of population dynamic features were highly variable across simulations. Results indicate that inferring extinction probabilities simply from the quantity of suitable habitat may underestimate extinction risks because this may ignore important interactions between life history traits and available habitat. Also, in dynamic range predictions uncertainty in SDM algorithms and climate scenarios can become secondary to uncertainty in dynamic model components. Our study emphasises the need for principal evaluation tools like sensitivity analysis in order to assess uncertainty and robustness in dynamic range predictions. A more direct benefit of such robustness analysis is an improved mechanistic understanding of dynamic species responses to climate change.}, language = {en} }