FPF-SB: a Scalable Algorithm for Microarray Gene Expression Data Clustering

Efficient and effective analysis of large datasets from microarray gene expression data is one of the keys to time-critical personalized medicine. The issue we address here is the scalability of the data processing software for clustering gene expression data into groups with homogeneous expression profile. In this paper we propose /FPF-SB/, a novel clustering algorithm based on a combination of the Furthest-Point-First (FPF) heuristic for solving the /k/-center problem and a stability-based method for determining the number of clusters /k/. Our algorithm improves the state of the art: it is scalable to large datasets without sacrificing output quality

K-Boost: a Scalable Algorithm for High-Quality Clustering of Microarray Gene Expression Data

Motivation: Microarray technology for profiling gene expression levels is a popular tool in modern biological research. Applications range from tissue classification to the detection of metabolic networks, from drug discovery to time-critical personalized medicine. Given the increase in size and complexity of the data sets produced, their analysis is becoming problematic in terms of time/quality tradeoffs. Clustering genes with similar expression profiles is a key initial step for subsequent manipulations and the increasing volumes of data to be analyzed requires methods that are at the same time efficient (completing an analysis in minutes rather than hours) and effective (identifying significant clusters with high biological correlations). Results: In this paper we propose K-Boost, a novel clustering algorithm based on a combination of the Furthest-Point-First (FPF) heuristic for solving the metric k-centers problem, a stability-based method for determining the number of clusters (i.e. the value of k), and a k-means-like cluster refinement. K-Boost is able to detect the optimal number of clusters to produce. It is scalable to large data-sets without sacrificing output quality as measured by several internal and external criteria

Risk of SARS-CoV-2 infection in migrants and ethnic minorities compared with the general population in the European WHO region during the first year of the pandemic. A systematic review

Background: Migrants and ethnic minorities have suffered a disproportionate impact of the COVID-19 pandemic compared to the general population from different perspectives. Our aim was to assess specifically their risk of infection in the 53 countries belonging to the World Health Organization European Region, during the first year of the pandemic. Methods: We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO CRD42021247326). We searched multiple databases for peer-reviewed literature, published on Medline, Embase, Scisearch, Biosis and Esbiobase in 2020 and preprints from PubMed up to 29/03/2021. We included cross-sectional, case-control, cohort, intervention, case-series, prevalence or ecological studies, reporting the risk of SARS-CoV-2 infection among migrants, refugees, and ethnic minorities. Results: Among the 1905 records screened, 25 met our inclusion criteria and were included in the final analysis. We found that migrants and ethnic minorities during the first wave of the pandemic were at increased exposure and risk of infection and were disproportionately represented among COVID-19 cases. However, the impact of COVID-19 on minorities does not seem homogeneous, since some ethnic groups seem to be more at risk than others. Risk factors include high-risk occupations, overcrowded accommodations, geographic distribution, social deprivation, barriers to access to information concerning preventive measures (due to the language barrier or to their marginality), together with biological and genetic susceptibilities. Conclusions: Although mixed methods studies will be required to fully understand the complex interplay between the various biological, social, and cultural factors underlying these findings, the impact of structural determinants of health is evident. Our findings corroborate the need to collect migration and ethnicity-disaggregated data and contribute to advocacy for inclusive policies and programmatic actions tailored to reach migrants and ethnic minorities

Patients perception of ionising radiation risks in CT ionising exposure. Does dose bill works?

Communicating to patients the magnitude of risk related to ionizing radiation exposure is problematic because of the uncertainty in estimates derived principally from epidemiological studies of large populations [1-6]. Euratom directive 59/2013 requires that dose bill will be part of the radiological report in European Countries [7]. However, how a risk is framed has a profound effect on risk perception. To date, no previous studies evaluated which could be the best way to make patient friendly dose bill. Our aim was to evaluate patients' perception of radiation exposure related to routine CT and their understanding after dose bill

PATIENTS' KNOWLEDGE AND AWARENESS OF RADIATION DOSE AND RISKS FROM CT: DO PATIENTS NEED A PERSONALIZED COMMUNICATION OF DOSE BILL?

In the last decades exposure to ionizing radiations in computed tomography (CT) has constantly increased. Only a few years ago it was quite difficult to assess how much radiation had been delivered to a patient during a CT examination. Nowadays, the technical challenges of dose data reporting between CT scanners from different vendors have been met, making dose tracking a reality since these dose data are automatically stored in the picture achieving system of the radiology department. Most authors affirm communication of CT risk to patients should be personalized, but no studies investigate if a tailored communication is needed. Aim of our study is to understand how patients' characteristics may condition the comprehension of this information

US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report

This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference

Coulomb dissociation of O-16 into He-4 and C-12

We measured the Coulomb dissociation of O-16 into He-4 and C-12 within the FAIR Phase-0 program at GSI Helmholtzzentrum fur Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section O-16(alpha,gamma)C-12, which is the time reversed reaction to C-12(alpha,gamma)O-16. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the (RB)-B-3 setup were necessary to cope with the high-intensity O-16 beam. All tracking detectors were designed to let the unreacted O-16 ions pass, while detecting the C-12 and He-4

Measurement of the CP-violating phase ϕs in B¯s0→Ds+Ds− decays

We present a measurement of the CP-violating weak mixing phase ϕs using the decay B¯0s→D+sD−s in a data sample corresponding to 3.0 fb−1 of integrated luminosity collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV. An analysis of the time evolution of the system, which does not use the constraint |λ|=1 to allow for the presence of CP violation in decay, yields ϕs=0.02±0.17(stat)±0.02(syst)  rad, |λ|=0.91+0.18−0.15(stat)±0.02(syst). This result is consistent with the standard model expectation