1,416 research outputs found
Stabilization of Linear Systems Over Gaussian Networks
The problem of remotely stabilizing a noisy linear time invariant plant over
a Gaussian relay network is addressed. The network is comprised of a sensor
node, a group of relay nodes and a remote controller. The sensor and the relay
nodes operate subject to an average transmit power constraint and they can
cooperate to communicate the observations of the plant's state to the remote
controller. The communication links between all nodes are modeled as Gaussian
channels. Necessary as well as sufficient conditions for mean-square
stabilization over various network topologies are derived. The sufficient
conditions are in general obtained using delay-free linear policies and the
necessary conditions are obtained using information theoretic tools. Different
settings where linear policies are optimal, asymptotically optimal (in certain
parameters of the system) and suboptimal have been identified. For the case
with noisy multi-dimensional sources controlled over scalar channels, it is
shown that linear time varying policies lead to minimum capacity requirements,
meeting the fundamental lower bound. For the case with noiseless sources and
parallel channels, non-linear policies which meet the lower bound have been
identified
Massive migration from the steppe is a source for Indo-European languages in Europe
We generated genome-wide data from 69 Europeans who lived between 8,000-3,000
years ago by enriching ancient DNA libraries for a target set of almost four
hundred thousand polymorphisms. Enrichment of these positions decreases the
sequencing required for genome-wide ancient DNA analysis by a median of around
250-fold, allowing us to study an order of magnitude more individuals than
previous studies and to obtain new insights about the past. We show that the
populations of western and far eastern Europe followed opposite trajectories
between 8,000-5,000 years ago. At the beginning of the Neolithic period in
Europe, ~8,000-7,000 years ago, closely related groups of early farmers
appeared in Germany, Hungary, and Spain, different from indigenous
hunter-gatherers, whereas Russia was inhabited by a distinctive population of
hunter-gatherers with high affinity to a ~24,000 year old Siberian6 . By
~6,000-5,000 years ago, a resurgence of hunter-gatherer ancestry had occurred
throughout much of Europe, but in Russia, the Yamnaya steppe herders of this
time were descended not only from the preceding eastern European
hunter-gatherers, but from a population of Near Eastern ancestry. Western and
Eastern Europe came into contact ~4,500 years ago, as the Late Neolithic Corded
Ware people from Germany traced ~3/4 of their ancestry to the Yamnaya,
documenting a massive migration into the heartland of Europe from its eastern
periphery. This steppe ancestry persisted in all sampled central Europeans
until at least ~3,000 years ago, and is ubiquitous in present-day Europeans.
These results provide support for the theory of a steppe origin of at least
some of the Indo-European languages of Europe
Microbial differences between dental plaque and historic dental calculus are related to oral biofilm maturation stage
Dental calculus, calcified oral plaque biofilm, contains microbial and host biomolecules that can be used to study historic microbiome communities and host responses. Dental calculus does not typically accumulate as much today as historically, and clinical oral microbiome research studies focus primarily on living dental plaque biofilm. However, plaque and calculus reflect different conditions of the oral biofilm, and the differences in microbial characteristics between the sample types have not yet been systematically explored. Here, we compare the microbial profiles of modern dental plaque, modern dental calculus, and historic dental calculus to establish expected differences between these substrates.- Background - Results -- Authentication of a preserved oral biofilm in calculus samples -- Dental calculus and plaque biofilm communities are distinct -- Health-associated communities of dental plaque and calculus are distinct -- Signatures of health and of disease are shared in modern and historic calculus samples -- Microbial community differences between health and disease in calculus are poorly resolved -- Absence of caries-specific microbial profiles in dental calculus -- Microbial co-exclusion patterns in plaque and calculus reflect biofilm maturity -- Microbial complexes in plaque and calculus -- Functional prediction in calculus is poorly predictive of health status -- Proteomic profiles of historic healthy site calculus -- Correlations between taxonomic, proteomic, and metabolomic profiles - Discussion - Conclusions - Materials and methods --Historic and modern calculus sample collection DNA extraction -- DNA library construction and high-throughput sequencing -- DNA sequence processing -- Genetic assessment of historic calculus sample preservation -- Genetic microbial taxonomic profiling -- Principal component analysis -- Assessment of differentially abundant taxa -- Sparse partial least squares-discriminant analysis -- Assessment of microbial co-exclusion patterns -- Gene functional categorization with SEED -- Proteomics -- Metabolomics -- Regularized canonical correlation analysi
Amlodipine+Benazepril is Superior to Hydrochlorothiazide+Benazepril Irrespective of Baseline Pulse Pressure: Subanalysis of the ACCOMPLISH Trial
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110751/1/jch12460.pd
Iron Age and Anglo-Saxon genomes from East England reveal British migration history
British population history has been shaped by a series of immigrations, including the early Anglo-Saxon migrations after 400 CE. It remains an open question how these events affected the genetic composition of the current British population. Here, we present whole-genome sequences from 10 individuals excavated close to Cambridge in the East of England, ranging from the late Iron Age to the middle Anglo-Saxon period. By analysing shared rare variants with hundreds of modern samples from Britain and Europe, we estimate that on average the contemporary East English population derives 38% of its ancestry from Anglo-Saxon migrations. We gain further insight with a new method, rarecoal, which infers population history and identifies fine-scale genetic ancestry from rare variants. Using rarecoal we find that the Anglo-Saxon samples are closely related to modern Dutch and Danish populations, while the Iron Age samples share ancestors with multiple Northern European populations including Britain
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