Regional Disparities in the European Union: Convergence and Agglomeration

Economic disparities between the regions of the European Union are of constant concern both for policy and economic research. In this paper we examine whether there are overlapping trends of regional development in the EU: overall convergence on the one hand and persistent or even increasing spatial concentration (agglomeration) on the other. Kernel density estimation, Markov chain analysis and cross-sectional regressions provide evidence that convergence of regional per-capita income in the EU15 has become considerably stronger in the 1990s. The reduction of income disparities, however, is a phenomenon between nations but not between regions within the EU countries. European integration (and possibly European regional policy) foster the catching-up of lagging countries but at the same time forces for agglomeration of economic activities tend to increase disparities within the EU member states. Obviously, the productive advantages of spatial proximity do not vanish in the knowledge economy.Regional growth; Agglomeration; Markov chains

Regional Disparities in the European Union: Convergence and Agglomeration

Economic disparities between the regions of the European Union are of constant concern both for policy and economic research. In this paper we examine whether there are overlapping trends of regional development in the EU: overall convergence on the one hand and persistent or even increasing spatial concentration (agglomeration) on the other. Kernel density estimation, Markov chain analysis and cross-sectional regressions provide evidence that convergence of regional per-capita income in the EU15 has become considerably stronger in the 1990s. The reduction of income disparities, however, is a phenomenon between nations but not between regions within the EU countries. European integration (and possibly European regional policy) foster the catching-up of lagging countries but at the same time forces for agglomeration of economic activities tend to increase disparities within the EU member states. Obviously, the productive advantages of spatial proximity do not vanish in the knowledge economy. --Regional growth,agglomeration,Markov chains

Regional disparities in the European Union: Convergence and Agglomeration

Economic disparities between the regions of the European Union are of constant concern both for policy and economic research. One of the “stylised facts” from the empirical literature is that the process of absolute convergence observed for decades has slowed down or even petered out during the 1980s. In this paper we analyse whether it has resumed and persisted in the 1990s when European integration made huge steps forward. We construct a typology of regions in order to examine whether there are overlapping trends of regional development, in particular, overall convergence on the one hand and persistent or even increasing spatial concentration (agglomeration) on the other. Both of our approaches, Marcov chain analysis and dynamic panel estimation, provide evidence that regional convergence in the EU15 has become stronger in the 1990s. At the same time there appears to exist a tendency towards further agglomeration of high income economic activities. Keywords: Regional growth, agglomeration, dynamic panel estimation

Nuclear Charge Radius of 12^{12}Be

The nuclear charge radius of $^{12}$Be was precisely determined using the technique of collinear laser spectroscopy on the $2s_{1/2}\rightarrow 2p_{1/2, 3/2}$ transition in the Be$^{+}$ ion. The mean square charge radius increases from $^{10}$Be to $^{12}$Be by \delta ^{10,12} = 0.69(5) \fm^{2} compared to \delta ^{10,11} = 0.49(5) \fm^{2} for the one-neutron halo isotope $^{11}$Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of $^{12}$Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure.Comment: 5 pages, 3 figure

Observation of the hyperfine transition in lithium-like Bismuth 209Bi80+^{209}\text{Bi}^{80+}: Towards a test of QED in strong magnetic fields

We performed a laser spectroscopic determination of the $2s$ hyperfine splitting (HFS) of Li-like $^{209}\text{Bi}^{80+}$ and repeated the measurement of the $1s$ HFS of H-like $^{209}\text{Bi}^{82+}$. Both ion species were subsequently stored in the Experimental Storage Ring at the GSI Helmholtzzentrum f\"ur Schwerionenforschung Darmstadt and cooled with an electron cooler at a velocity of $\approx 0.71\,c$. Pulsed laser excitation of the $M1$ hyperfine-transition was performed in anticollinear and collinear geometry for $\text{Bi}^{82+}$ and $\text{Bi}^{80+}$, respectively, and observed by fluorescence detection. We obtain $\Delta E^{(1s)}= 5086.3(11)\,\textrm{meV}$ for $\text{Bi}^{82+}$, different from the literature value, and $\Delta E^{(2s)}= 797.50(18)\,\textrm{meV}$ for $\text{Bi}^{80+}$. These values provide experimental evidence that a specific difference between the two splitting energies can be used to test QED calculations in the strongest static magnetic fields available in the laboratory independent of nuclear structure effects. The experimental result is in excellent agreement with the theoretical prediction and confirms the sum of the Dirac term and the relativistic interelectronic-interaction correction at a level of 0.5% confirming the importance of accounting for the Breit interaction.Comment: 5 pages, 2 figure

Collinear laser spectroscopy of atomic cadmium

Hyperfine structure $A$ and $B$ factors of the atomic 5s\,5p\,\; ^3\rm{P}_2 \rightarrow 5s\,6s\,\; ^3\rm{S}_1 transition are determined from collinear laser spectroscopy data of $^{107-123}$Cd and $^{111m-123m}$Cd. Nuclear magnetic moments and electric quadrupole moments are extracted using reference dipole moments and calculated electric field gradients, respectively. The hyperfine structure anomaly for isotopes with $s_{1/2}$ and $d_{5/2}$ nuclear ground states and isomeric $h_{11/2}$ states is evaluated and a linear relationship is observed for all nuclear states except $s_{1/2}$. This corresponds to the Moskowitz-Lombardi rule that was established in the mercury region of the nuclear chart but in the case of cadmium the slope is distinctively smaller than for mercury. In total four atomic and ionic levels were analyzed and all of them exhibit a similar behaviour. The electric field gradient for the atomic 5s\,5p\,\; ^3\mathrm{P}_2 level is derived from multi-configuration Dirac-Hartree-Fock calculations in order to evaluate the spectroscopic nuclear quadrupole moments. The results are consistent with those obtained in an ionic transition and based on a similar calculation.Comment: 12 pages, 5 figure

Creative beyond TikToks : investigating adolescents' social privacy management on TikTok

TikTok has been criticized for its low privacy standards, but little is known about how its adolescent users protect their privacy. Based on interviews with 54 adolescents in Switzerland, this study provides a comprehensive understanding of young TikTok users' privacy management practices related to the creation of videos. The data were explored using the COM-B model, an established behavioral analysis framework adapted for sociotechnical privacy research. Our overall findings are in line with previous research on other social networks: adolescents are aware of privacy related to their online social connections (social privacy) and perform conscious privacy management. However, we also identified new patterns related to the central role of algorithmic recommendations potentially relevant for other social networks. Adolescents are aware that TikTok's special algorithm, combined with the app's high prevalence among their peers, could easily put them in the spotlight. Some adolescents also reduce TikTok, which was originally conceived as a social network, to its extensive audio-visual capabilities and share TikToks via more private channels (e.g., Snapchat) to manage audiences and avoid identification by peers. Young users also find other creative ways to protect their privacy such as identifying stalkers or maintaining multiple user accounts with different privacy settings to establish granular audience management. Based on our findings, we propose various concrete measures to develop interventions that protect the privacy of adolescents on TikTok