15,791 research outputs found
Maximizing the Sum Rate in Cellular Networks Using Multi-Convex Optimization
In this paper, we propose a novel algorithm to maximize the sum rate in
interference-limited scenarios where each user decodes its own message with the
presence of unknown interferences and noise considering the
signal-to-interference-plus-noise-ratio. It is known that the problem of
adapting the transmit and receive filters of the users to maximize the sum rate
with a sum transmit power constraint is non-convex. Our novel approach is to
formulate the sum rate maximization problem as an equivalent multi-convex
optimization problem by adding two sets of auxiliary variables. An iterative
algorithm which alternatingly adjusts the system variables and the auxiliary
variables is proposed to solve the multi-convex optimization problem. The
proposed algorithm is applied to a downlink cellular scenario consisting of
several cells each of which contains a base station serving several mobile
stations. We examine the two cases, with or without several half-duplex
amplify-and-forward relays assisting the transmission. A sum power constraint
at the base stations and a sum power constraint at the relays are assumed.
Finally, we show that the proposed multi-convex formulation of the sum rate
maximization problem is applicable to many other wireless systems in which the
estimated data symbols are multi-affine functions of the system variables.Comment: 24 pages, 5 figure
Many Labs 2 : Investigating Variation in Replicability Across Sample and Setting
We conducted preregistered replications of 28 classic and contemporary published findings with protocols that were peer reviewed in advance to examine variation in effect magnitudes across sample and setting. Each protocol was administered to approximately half of 125 samples and 15,305 total participants from 36 countries and territories. Using conventional statistical significance (p < .05), fifteen (54%) of the replications provided evidence in the same direction and statistically significant as the original finding. With a strict significance criterion (p < .0001), fourteen (50%) provide such evidence reflecting the extremely high powered design. Seven (25%) of the replications had effect sizes larger than the original finding and 21 (75%) had effect sizes smaller than the original finding. The median comparable Cohen’s d effect sizes for original findings was 0.60 and for replications was 0.15. Sixteen replications (57%) had small effect sizes (< .20) and 9 (32%) were in the opposite direction from the original finding. Across settings, 11 (39%) showed significant heterogeneity using the Q statistic and most of those were among the findings eliciting the largest overall effect sizes; only one effect that was near zero in the aggregate showed significant heterogeneity. Only one effect showed a Tau > 0.20 indicating moderate heterogeneity. Nine others had a Tau near or slightly above 0.10 indicating slight heterogeneity. In moderation tests, very little heterogeneity was attributable to task order, administration in lab versus online, and exploratory WEIRD versus less WEIRD culture comparisons. Cumulatively, variability in observed effect sizes was more attributable to the effect being studied than the sample or setting in which it was studied.
Data, materials and code available at: https://osf.io/8cd4r/</a
Early intervention and intensive management of patients with diabetes, cardiorenal, and metabolic diseases
Increasing rates of obesity and diabetes have driven corresponding increases in related cardiorenal and metabolic diseases. In many patients, these conditions occur together, further increasing morbidity and mortality risks to the individual. Yet all too often, the risk factors for these disorders are not addressed promptly in clinical practice, leading to irreversible pathologic progression. To address this gap, we convened a Task Force of experts in cardiology, nephrology, endocrinology, and primary care to develop recommendations for early identification and intervention in obesity, diabetes, and other cardiorenal and metabolic diseases. The recommendations include screening and diagnosis, early interventions with lifestyle, and when and how to implement medical therapies. These recommendations are organized into primary and secondary prevention along the continuum from obesity through the metabolic syndrome, prediabetes, diabetes, hypertension, dyslipidemia, nonalcoholic fatty liver disease (NAFLD), atherosclerotic cardiovascular disease (ASCVD) and atrial fibrillation, chronic kidney disease (CKD), and heart failure (HF). The goal of early and intensive intervention is primary prevention of comorbidities or secondary prevention to decrease further worsening of disease and reduce morbidity and mortality. These efforts will reduce clinical inertia and may improve patients\u27 well-being and adherence
Cost Sharing Games for Energy-Efficient Multi-Hop Broadcast in Wireless Networks
We study multi-hop broadcast in wireless networks with one source node and
multiple receiving nodes. The message flow from the source to the receivers can
be modeled as a tree-graph, called broadcast-tree. The problem of finding the
minimum-power broadcast-tree (MPBT) is NP-complete. Unlike most of the existing
centralized approaches, we propose a decentralized algorithm, based on a
non-cooperative cost-sharing game. In this game, every receiving node, as a
player, chooses another node of the network as its respective transmitting node
for receiving the message. Consequently, a cost is assigned to the receiving
node based on the power imposed on its chosen transmitting node. In our model,
the total required power at a transmitting node consists of (i) the transmit
power and (ii) the circuitry power needed for communication hardware modules.
We develop our algorithm using the marginal contribution (MC) cost-sharing
scheme and show that the optimum broadcast-tree is always a Nash equilibrium
(NE) of the game. Simulation results demonstrate that our proposed algorithm
outperforms conventional algorithms for the MPBT problem. Besides, we show that
the circuitry power, which is usually ignored by existing algorithms,
significantly impacts the energy-efficiency of the network.Comment: 33 pages including references, figures, and table
Biclonal myelodysplastic syndrome involving six chromosomes and monoallelic loss of RB1 - A rare case
<p>Abstract</p> <p>Background</p> <p>Myelodysplastic syndrome (MDS) represents a group of clonal hematological disorders characterized by progressive cytopenia, and reflects to defects in erythroid, myeloid and megakaryocytic maturation. MDS is more frequently observed in older aged patients with cytogenetic abnormalities like monosomy of chromosome(s) 5 and/or 7. In 50% of de novo MDS cases, chromosomal aberrations are found and rearrangements involving the retinoblastoma (<it>RB1</it>) gene in 13q14 are found.</p> <p>Results</p> <p>Here, we are presenting a case report of a rare biclonal MDS with a karyotype of 45, XY,-4, der(6)t(4;6)(p15.1;p21.3), der(8)t(4;8)(q31.2;q22), t(13;16)(q21.3;p11.2)<abbrgrp><abbr bid="B11">11</abbr></abbrgrp>/45, XY, der(7)t(7;13)(p22.2~22.3;q21.3),-13 <abbrgrp><abbr bid="B9">9</abbr></abbrgrp>. The patient was diagnosed according to WHO classification as refractory anemia with excess of blasts (RAEB-II).</p> <p>Immunophenotyping was positive for CD11b, CD11c, CD10, CD13, CD15, CD16 and CD33.</p> <p>Conclusion</p> <p>We report, a novel and cytogenetically rare case of a biclonal MDS with complex chromosomal aberrations and deletion of <it>RB1</it>-gene in both clones. These findings are associated with a poor prognosis as the patient died 3 months after diagnosis.</p
EFSA Guidance Document for evaluating laboratory and field dissipation studies to obtain DegT50 values of active substances of plant protection products and transformation products of these active substances in soil
EFSA was asked by the European Commission to prepare a Guidance of EFSA for evaluating laboratory and field dissipation studies to obtain degradation rate parameters (DegT50matrix values) of active substances of plant protection products and transformation products of these active substances in soil. This EFSA Guidance Document provides guidance for users on how to obtain DegT50matrix values when performing risk assessments according to Regulation EC No 1107/2009 of the European Parliament and the Council. In addition, this document provides guidance on adsorption parameter (Koc) selection and new Crop Interception values
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