A5069314096- Gene Regulatory Network Analysis
- Pluripotent Stem Cells Research
- Genetics, Aging, and Longevity in Model Organisms
- Single-cell and spatial transcriptomics
- Cell Image Analysis Techniques
- Neural dynamics and brain function
- Fungal and yeast genetics research
- Photoreceptor and optogenetics research
- Developmental Biology and Gene Regulation
- Cooperative Communication and Network Coding
- Advanced Wireless Network Optimization
- Gene expression and cancer classification
- Network Traffic and Congestion Control
- Microbial Metabolic Engineering and Bioproduction
- Mobile Ad Hoc Networks
- Neuroscience and Neural Engineering
- Planarian Biology and Electrostimulation
- CRISPR and Genetic Engineering
- stochastic dynamics and bifurcation
- Theoretical and Computational Physics
- Advanced Graph Theory Research
- Software-Defined Networks and 5G
- Advanced Optical Network Technologies
- Interconnection Networks and Systems
- Elasticity and Wave Propagation
Harvard University
2015-2024
Harvard University Press
2007-2024
Harvard Stem Cell Institute
2011-2023
Tamil Nadu Agricultural University
2021-2022
Quantitative BioSciences
2018-2020
Center for Systems Biology
2007-2017
Allen Institute
2016-2017
Allen Institute for Brain Science
2016-2017
Alcatel Lucent (Germany)
2002-2007
McGill University
2005
Competition between random genetic drift and natural selection plays a central role in evolution: Whereas non-beneficial mutations often prevail small populations by chance, that sweep through large typically confer selective advantage. Here, however, we observe chance effects during range expansions dramatically alter the gene pool even microbial populations. Initially well-mixed of two fluorescently labeled strains Escherichia coli develop well-defined, sector-like regions with fractal...
Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to differentiated cell state. Here, asked mouse embryonic stem cells (ESCs) leave state and choose between germ layer fates. By analyzing dynamics of circuit that maintains pluripotency, found Oct4 Sox2, proteins maintain ESC identity, also orchestrate selection. suppresses neural ectodermal differentiation promotes mesendodermal...
Biological systems involving short-range activators and long-range inhibitors can generate complex patterns. Reaction-diffusion models postulate that differences in signaling range are caused by differential diffusivity of inhibitor activator. Other suggest clearance underlies different ranges. To test these models, we measured the biophysical properties Nodal/Lefty activator/inhibitor system during zebrafish embryogenesis. Analysis Nodal Lefty gradients revealed Nodals have a shorter than...
Simple models for ruptures along a heterogeneous earthquake fault zone are studied, focusing on the interplay between roles of disorder and dynamical effects. A class found to operate naturally at critical point whose properties yield power-law scaling statistics. Various effects can change behavior distribution small events combined with characteristic system size events. The studies employ various analytic methods as well simulations.
Signaling pathways relay information about changes in the external environment so that cells can respond appropriately. How much a pathway carry depends on its bandwidth. We designed microfluidic device to reliably change of single over range frequencies. Using this device, we measured bandwidth Saccharomyces cerevisiae signaling responds high osmolarity. This prototypical pathway, HOG is shown act as low-pass filter, integrating signal when it rapidly and following faithfully more slowly....
Channel assignment problems in the time, frequency and code domains have thus far been studied separately. Exploiting similarity of "constraints" that characterize assignments within across these domains, we introduce first unified framework for study problems. Our identifies eleven atomic constraints underlying most current potential problems, characterizes a problem as combination constraints. Based on this framework, present algorithm efficient (T/F/C)DMA channel to nodes or inter-nodal...
Abstract Morphogen signals are essential for cell fate specification during embryogenesis. Some receptors that sense these morphogens known to localize only the apical or basolateral membrane of polarized lines in vitro. How such localization affects morphogen sensing and patterning developing embryo remains unknown. Here, we show formation a robust BMP signaling gradient early mouse depends on restricted, receptors. The mis-localization results ectopic epiblast vivo. With evidence from...
The dynamics of tensile crack fronts restricted to advance in a plane are studied. In an ideal linear elastic medium, propagating mode along the front with velocity slightly less than Rayleigh wave velocity, is found exist. But dependence effective fracture toughness $\ensuremath{\gamma}(v)$ on shown destabilize if $\frac{d\ensuremath{\gamma}}{\mathrm{dv}}<0$. Short wavelength radiation due weak random heterogeneities tends lead this instability at low velocities. implications these results...
We formulate the problem of multicast tree generation as one computing a directed Steiner minimal cost. In this context, we present polynomial-time algorithm that provides for trade-off selection, using single parameter /spl kappa/, between tree-cost (Steiner cost) and run time efficiency. Further, same may be used delay optimization or minimization simply by configuring value kappa/ appropriately. theoretical experimental analysis characterizing performance our algorithm. Theoretically,...
The dynamics of a single crack moving through heterogeneous medium is studied in the quasi-static approximation. Equations motion for front are formulated and resulting scaling behaviour analyzed. In model scalar system mode III (tearing) cracks, surface found to be self affine with roughness exponent $\zeta=1/2$. But usual experimental case I (tensile) local preference causes only logarithmically rough, quite unlike those seen experiments. effects residual stresses considered found,...
New algorithms for transmission scheduling in multihop broadcast radio networks are presented. Both link and considered. In each instance given that improve upon existing both theoretically experimentally. Theoretically, it is shown tree can be scheduled optimally, arbitrary so the schedule bounded by a length proportional to function of network thickness times optimum. Previous could guarantee only schedules were no worse than maximum node degree, presented here represent considerable...
Abstract Despite its high prevalence among dementias, Lewy body dementia (LBD) remains poorly understood with a limited, albeit growing, evidence base. The public‐health burden that LBD imposes is worsened by overlapping pathologies, which contribute to misdiagnosis, and lack of treatments. For this report, we gathered analyzed public‐domain information on advocacy, funding, research outputs, the therapeutic pipeline identify gaps in each these key elements. To further understand current...
We present a routing paradigm called PBR that utilizes steepest gradient search methods to route data packets. More specifically, the assigns scalar potentials network elements and forwards packets in direction of maximum positive force. show family schemes are loop free standard shortest path algorithms special case paradigm. then how design potential function accounts for traffic conditions at node. The resulting algorithm routes around congested areas while preserving key desirable...
The dynamics of planar crack fronts in hetergeneous media near the critical load for onset motion are investigated both analytically and by numerical simulations. Elasticity solid leads to long-range stress transfer along front which is nonmonotonic time due elastic waves medium. In quasistatic limit with instantaneous transfer, exhibits dynamic phenomenon, a second-order-like transition from pinned moving phase as applied increased through value. At criticality, self-affine, roughness...