Plato\u27s Political Philosophy (abstract)

Plato had one consistent theory of politics; the Republic, Politicus, and Laws form a unity, complementary rather than contradictory. These dialogues are all theoretical, none provides a blueprint for political action. Political theory establishes the standard by which we must judge and thus allows us to act according to an aim

The Idea of Progress in Classical Antiquity

Originally published in 1967. Ludwig Edelstein characterizes the idea of "progress" in Greek and Roman times. He analyzes the ancients' belief in "a tendency inherent in nature or in man to pass through a regular sequence of stages of development in past, present, and future, the latter stages being—with perhaps occasional retardations or minor regressions—superior to the earlier." Edelstein's contemporaries asserted that the Greeks and Romans were entirely ignorant of a belief in progress in this sense of the term. In arguing against this dominant thesis, Edelstein draws from the conclusions of scholars of the nineteenth and early twentieth centuries and discusses ideas of Auguste Comte and Wilhelm Dilthey

Vocational Education and Training and Transitions into the Labor Market

Stage 6 of the German National Educational Panel Study (NEPS) 6 is devoted to the transition of young people from school to work. Stage 6 focuses in particular on the transition from school to vocational education and training and then to work (for tertiary education, see Chap. 16). In all Western societies, vocational education and training (VET) systems face a number of challenges, including the need to adapt to increasing skill requirements across the economy and to handle the danger of producing an "underclass" of low-skilled youth. This chapter presents the life-course approach for investigating school-leavers' pathways from school into the labor market within NEPS. Several factors shape young people’s school-to-work transitions: their motivation and competence endowment, their decisions to apply for specific educational programs, the constraints they face regarding the opportunities for VET programs and the gatekeepers’ recruitment behavior, the information and support youths may or may not receive from social networks, and the learning environments they encounter in firms and schools. We outline the basic theories that guide our research concerning these influences and discuss how we take them into account within NEPS Stage 6. Thus, we provide an overview of the study’s research potential in the area of VET. For now, it is mainly the Scientific Use Files of Starting Cohort 4 (SC4) that provide ample opportunities for innovative interdisciplinary analyses - including analyses of students from special education schools. As the starting cohorts age, Starting Cohort 3 (SC3) has now also entered NEPS Stage 6 and its data on VET transitions will soon be available as well

Spatio-temporal Models of Lymphangiogenesis in Wound Healing

Several studies suggest that one possible cause of impaired wound healing is failed or insufficient lymphangiogenesis, that is the formation of new lymphatic capillaries. Although many mathematical models have been developed to describe the formation of blood capillaries (angiogenesis), very few have been proposed for the regeneration of the lymphatic network. Lymphangiogenesis is a markedly different process from angiogenesis, occurring at different times and in response to different chemical stimuli. Two main hypotheses have been proposed: 1) lymphatic capillaries sprout from existing interrupted ones at the edge of the wound in analogy to the blood angiogenesis case; 2) lymphatic endothelial cells first pool in the wound region following the lymph flow and then, once sufficiently populated, start to form a network. Here we present two PDE models describing lymphangiogenesis according to these two different hypotheses. Further, we include the effect of advection due to interstitial flow and lymph flow coming from open capillaries. The variables represent different cell densities and growth factor concentrations, and where possible the parameters are estimated from biological data. The models are then solved numerically and the results are compared with the available biological literature.Comment: 29 pages, 9 Figures, 6 Tables (39 figure files in total

EHD2 is a mechanotransducer connecting caveolae dynamics with gene transcription

Caveolae are small invaginated pits that function as dynamic mechanosensors to buffer tension variations at the plasma membrane. Here we show that under mechanical stress, the EHD2 ATPase is rapidly released from caveolae, SUMOylated, and translocated to the nucleus, where it regulates the transcription of several genes including those coding for caveolae constituents. We also found that EHD2 is required to maintain the caveolae reservoir at the plasma membrane during the variations of membrane tension induced by mechanical stress. Metal-replica electron microscopy of breast cancer cells lacking EHD2 revealed a complete absence of caveolae and a lack of gene regulation under mechanical stress. Expressing EHD2 was sufficient to restore both functions in these cells. Our findings therefore define EHD2 as a central player in mechanotransduction connecting the disassembly of the caveolae reservoir with the regulation of gene transcription under mechanical stress

fMRI scanner noise interaction with affective neural processes

The purpose of the present study was the investigation of interaction effects between functional MRI scanner noise and affective neural processes. Stimuli comprised of psychoacoustically balanced musical pieces, expressing three different emotions (fear, neutral, joy). Participants (N=34, 19 female) were split into two groups, one subjected to continuous scanning and another subjected to sparse temporal scanning that features decreased scanner noise. Tests for interaction effects between scanning group (sparse/quieter vs continuous/noisier) and emotion (fear, neutral, joy) were performed. Results revealed interactions between the affective expression of stimuli and scanning group localized in bilateral auditory cortex, insula and visual cortex (calcarine sulcus). Post-hoc comparisons revealed that during sparse scanning, but not during continuous scanning, BOLD signals were significantly stronger for joy than for fear, as well as stronger for fear than for neutral in bilateral auditory cortex. During continuous scanning, but not during sparse scanning, BOLD signals were significantly stronger for joy than for neutral in the left auditory cortex and for joy than for fear in the calcarine sulcus. To the authors' knowledge, this is the first study to show a statistical interaction effect between scanner noise and affective processes and extends evidence suggesting scanner noise to be an important factor in functional MRI research that can affect and distort affective brain processes