Single-cell protein dynamics reproduce universal fluctuations in cell populations

Protein variability in single cells has been studied extensively in populations, but little is known about temporal protein fluctuations in a single cell over extended times. We present here traces of protein copy number measured in individual bacteria over multiple generations and investigate their statistical properties, comparing them to previously measured population snapshots. We find that temporal fluctuations in individual traces exhibit the same universal features as those previously observed in populations. Scaled fluctuations around the mean of each trace exhibit the same universal distribution shape as found in populations measured under a wide range of conditions and in two distinct microorganisms. Additionally, the mean and variance of the traces over time obey the same quadratic relation. Analyzing the temporal features of the protein traces in individual cells, reveals that within a cell cycle protein content increases as an exponential function with a rate that varies from cycle to cycle. This leads to a compact description of the protein trace as a 3-variable stochastic process - the exponential rate, the cell-cycle duration and the value at the cycle start - sampled once each cell cycle. This compact description is sufficient to preserve the universal statistical properties of the protein fluctuations, namely, the protein distribution shape and the quadratic relationship between variance and mean. Our results show that the protein distribution shape is insensitive to sub-cycle intracellular microscopic details and reflects global cellular properties that fluctuate between generations

Willkommensbesuche in NRW als Instrument vorbeugender Sozialpolitik: Ergebnisse einer quantitativen Untersuchung

In Willkommensbesuchen werden Familien mit Neugeborenen zu Hause besucht, damit sie über familienrelevante Angebote informiert werden können. 113 Netzwerkkoordinierende wurden mit einem Online-Fragebogen zu Willkommensbesuchen befragt. Willkommensbesuche in NRW stellen sich als ins-gesamt leicht zugängliches und in vielerlei Hinsicht vorbeugendes Angebot dar. Es werden aktuelle Ziele, Durchführungsformen, Rahmenbedingungen, Ergebnisse und Entwicklungschancen erörtert und die sich daraus ergebenden An-regungen für Forschung und Praxis diskutiert

Ratchet-Like Solitonic Transport in Quantum Hall Bilayers

The pseudo-spin model for double layer quantum Hall system with total landau level filling factor $\nu=1$ is discussed. Unlike the "traditional" one where interlayer voltage enters as static magnetic field along pseudo- spin hard axis, in our model we consider applied interlayer voltage as a frequency of precessing pseudo-magnetic field lying into the easy plane. It is shown that a Landau-Lifshitz equation for the considered pseudo magnetic system well describes existing experimental data. Besides that, the mentioned model predicts novel directed intra-layer transport phenomenon in the system: unidirectional intra-layer energy transport is realized due to interlayer voltage induced motion of topological kinks. This effect could be observed experimentally detecting counter-propagating intra-layer inhomogeneous charge currents which are proportional to the interlayer voltage and total topological charge of the pseudo-spin system.Comment: 4 pages, 4 figure

Willkommensbesuche in NRW als Instrument vorbeugender Sozialpolitik

WILLKOMMENSBESUCHE IN NRW ALS INSTRUMENT VORBEUGENDER SOZIALPOLITIK Willkommensbesuche in NRW als Instrument vorbeugender Sozialpolitik / Froncek, Benjamin (Rights reserved) ( -

Constructing 3D crystal templates for photonic band gap materials using holographic optical tweezers

A simple and robust method is presented for the construction of 3-dimensional crystals from silica and polystyrene microspheres. The crystals are suitable for use as templates in the production of three-dimensional photonic band gap (PBG) materials. Manipulation of the microspheres was achieved using a dynamic holographic assembler (DHA) consisting of computer controlled holographic optical tweezers. Attachment of the microspheres was achieved by adjusting their colloidal interactions during assembly. The method is demonstrated by constructing a variety of 3-dimensional crystals using spheres ranging in size from 3 µm down to 800 nm. A major advantage of the technique is that it may be used to build structures that cannot be made using self-assembly. This is illustrated through the construction of crystals in which line defects have been deliberately included, and by building simple cubic structures

Interaction of matter-wave gap solitons in optical lattices

We study mobility and interaction of gap solitons in a Bose-Einstein condensate (BEC) confined by an optical lattice potential. Such localized wavepackets can exist only in the gaps of the matter-wave band-gap spectrum and their interaction properties are shown to serve as a measure of discreteness imposed onto a BEC by the lattice potential. We show that inelastic collisions of two weakly localized near-the-band-edge gap solitons provide simple and effective means for generating strongly localized in-gap solitons through soliton fusion.Comment: 12 pages, 7 figure

Health-related quality of life in rural children living in four European countries: the GABRIEL study

Objective: Measuring children's health-related quality of life (HRQOL) is of growing importance given increasing chronic diseases. By integrating HRQOL questions into the European GABRIEL study, we assessed differences in HRQOL between rural farm and non-farm children from Germany, Austria, Switzerland and Poland to relate it to common childhood health problems and to compare it to a representative, mostly urban German population sample (KIGGS). Methods: The parents of 10,400 school-aged children answered comprehensive questionnaires including health-related questions and the KINDL-R questions assessing HRQOL. Results: Austrian children reported highest KINDL-R scores (mean: 80.9; 95% CI [80.4, 81.4]) and Polish children the lowest (74.5; [73.9, 75.0]). Farm children reported higher KINDL-R scores than non-farm children (p=0.002). Significantly lower scores were observed in children with allergic diseases (p<0.001), with sleeping difficulties (p<0.001) and in overweight children (p=0.04). The German GABRIEL sample reported higher mean scores (age 7-10years: 80.1, [79.9, 80.4]; age 11-13years: 77.1, [74.9, 79.2]) compared to the urban KIGGS study (age 7-10years: 79.0, [78.7-79.3]; age 11-13years: 75.1 [74.6-75.6]). Socio-demographic or health-related factors could not explain differences in HRQOL between countries. Conclusions: Future increases in chronic diseases may negatively impact children's HRQO