478 research outputs found
Kraichnan-Leith-Batchelor similarity theory and two-dimensional inverse cascades
No full textWe study the scaling properties and Kraichnan-Leith-Batchelor (KLB) theory of forced inverse cascades in generalized two-dimensional (2D) fluids (-turbulence models) simulated at resolution . We consider (surface quasigeostrophic flow), (2D vorticity dynamics) and . The forcing scale is well-resolved, a direct cascade is present and there is no large-scale dissipation. Coherent vortices spanning a range of sizes, most larger than the forcing scale, are present for both and . The active scalar field for contains comparatively few and small vortices. The energy spectral slopes in the inverse cascade are steeper than the KLB prediction in all three systems. Since we stop the simulations well before the cascades have reached the domain scale, vortex formation and spectral steepening are not due to condensation effects; nor are they caused by large-scale dissipation, which is absent. One- and two-point pdfs, hyperflatness factors and structure functions indicate that the inverse cascades are intermittent and non-Gaussian over much of the inertial range for and , while the inverse cascade is much closer to Gaussian and non-intermittent. For the steep spectrum is close to that associated with enstrophy equipartition. Continuous wavelet analysis shows approximate KLB scaling () and () in the interstitial regions between the coherent vortices. Our results demonstrate that coherent vortex formation ( and ) and non-realizability () cause 2D inverse cascades to deviate from the KLB predictions, but that the flow between the vortices exhibits KLB scaling and non-intermittent statistics for and . The results will appear in \cite{BurgessEA2015}, which has been accepted to the \emph{Journal of Fluid Mechanics}
Soluble and multivalent Jag1 DNA origami nanopatterns activate Notch without pulling force
No full textFunding Information: The authors would like to acknowledge support from the NIH grant number R35GM133482 for V.C.L., the Knut and Alice Wallenberg Foundation (Grants KAW 2017.0114 for B.H. and A.I.T. and KAW 2017.0276 for B.H.), from the European Research Council ERC for B.H. (Acronym: Cell Track GA No. 724872) and A.I.T (Acronym: MechComm GA No. 617711), and from the Swedish Research Council for B.H. (grant no. 2019-01474) and from the Göran Gustafsson Foundation for B.H. And from the Academy of Finland for B.S. (grant no. 341908). lt-NES samples were obtained from, and initial culture protocols was made possible with the help of Anna Falk’s team and the iPS Core facility at Karolinska Institutet. Part of this work was performed at the Karolinska Institutet/SciLifeLab Protein Science Core Facility (PSF). Part of this work was performed at the Karolinska Institutet Biomedicum Imaging Core (BIC). EM data was collected at the Karolinska Institutet 3D-EM facility. Publisher Copyright: © 2024, The Author(s).The Notch signaling pathway has fundamental roles in embryonic development and in the nervous system. The current model of receptor activation involves initiation via a force-induced conformational change. Here, we define conditions that reveal pulling force-independent Notch activation using soluble multivalent constructs. We treat neuroepithelial stem-like cells with molecularly precise ligand nanopatterns displayed from solution using DNA origami. Notch signaling follows with clusters of Jag1, and with chimeric structures where most Jag1 proteins are replaced by other binders not targeting Notch. Our data rule out several confounding factors and suggest a model where Jag1 activates Notch upon prolonged binding without appearing to need a pulling force. These findings reveal a distinct mode of activation of Notch and lay the foundation for the development of soluble agonists.Peer reviewe
Multimode interference couplers: Design and applications
No full textElectrical Engineering, Mathematics and Computer Scienc
High Capacity Integrated Optical Receivers
No full textElectrical Engineering, Mathematics and Computer Scienc
InP-based Photonic Integrated Circuits for Wavelength Routing and Switching
No full textElectrical Engineering, Mathematics and Computer Scienc
Phased-array wavelength demultiplexers and their integration with photodetectors
No full textElectrical Engineering, Mathematics and Computer Scienc
Compact integrated optical components for telecommunication networks
No full textElectrical Engineering, Mathematics and Computer Scienc
Educational Problems Among Children Of The Nomadic Tribes In Karnataka
No full textEducation is widely recognized as a critical instrument in the global social inclusion process, particularly within India\u27s context. However, educational development in India exhibits significant disparities, particularly among various tribal communities. Nomadic tribes, in particular, face notable challenges and are markedly behind in educational attainment. Presently, children belonging to nomadic tribes continue to experience educational exclusion, impeding their integration into mainstream society. This lack of educational access contributes to their socio-economic and political marginalization. Consequently, this study aims to address the educational deficiencies among nomadic tribal children and facilitate their integration into broader societal frameworks. This research aims to investigate the economic circumstances of nomadic tribes and the educational hurdles faced by their children. Data was sourced from both primary and secondary outlets. Primary data was collected through a sample of 60 respondents, comprising 15 individuals each from Iruliga, Hakki-Pikki, Malekudiya, and Medar tribes, selected via a simple random sampling approach. The study underlines that educational development among children from nomadic tribes remains significantly behind expectations
Optische eigenschappen van halfgeleider lasers en laser versterkers voor glasvezel telecommunicatie
No full textElectrical Engineering, Mathematics and Computer Scienc
- …
