716 research outputs found
Fundamental Concepts of Cyber Resilience: Introduction and Overview
Given the rapid evolution of threats to cyber systems, new management
approaches are needed that address risk across all interdependent domains
(i.e., physical, information, cognitive, and social) of cyber systems. Further,
the traditional approach of hardening of cyber systems against identified
threats has proven to be impossible. Therefore, in the same way that biological
systems develop immunity as a way to respond to infections and other attacks,
so too must cyber systems adapt to ever-changing threats that continue to
attack vital system functions, and to bounce back from the effects of the
attacks. Here, we explain the basic concepts of resilience in the context of
systems, discuss related properties, and make business case of cyber
resilience. We also offer a brief summary of ways to assess cyber resilience of
a system, and approaches to improving cyber resilience.Comment: This is a preprint version of a chapter that appears in the book
"Cyber Resilience of Systems and Networks," Springer 201
Long term follow up after surgery in congenitally corrected transposition of the great arteries with a right ventricle in the systemic circulation
Aim of the study: To investigate the long-term outcome of surgical treatment for congenitally corrected transposition of the great arteries (CCTGA), in patients with biventricular repair with the right ventricle as systemic ventricle.Methods: A total of 32 patients with CCTGA were operated between January 1972 and October 2008. These operations comprised 18 patients with a repair with a normal left ventricular outflow tract, 11 patients with a Rastelli repair of the left ventricle to the pulmonary artery and 3 patients with a cardiac transplantation.Results: Excluding the cardiac transplantation patients, mean age at operation was 16 years (sd 15 years, range 1 week - 49 years). Median follow-up was 12 years (sd 10 years, range 7 days - 32 years). Survival obtained from Kaplan-Meier analysis at 20 years after surgery was 63% (CI 53-73%). For the non-Rastelli group these data at 20 years were
Benefit of warm water immersion on biventricular function in patients with chronic heart failure
Targeting of the Human Coagulation Factor IX Gene at rDNA Locus of Human Embryonic Stem Cells
BACKGROUND: Genetic modification is a prerequisite to realizing the full potential of human embryonic stem cells (hESCs) in human genetic research and regenerative medicine. Unfortunately, the random integration methods that have been the primary techniques used keep creating problems, and the primary alternative method, gene targeting, has been effective in manipulating mouse embryonic stem cells (mESCs) but poorly in hESCs. METHODOLOGY/PRINCIPAL FINDINGS: Human ribosomal DNA (rDNA) repeats are clustered on the short arm of acrocentric chromosomes. They consist of approximately 400 copies of the 45S pre-RNA (rRNA) gene per haploid. In the present study, we targeted a physiological gene, human coagulation factor IX, into the rDNA locus of hESCs via homologous recombination. The relative gene targeting efficiency (>50%) and homologous recombination frequency (>10(-5)) were more than 10-fold higher than those of loci targeted in previous reports. Meanwhile, the targeted clones retained both a normal karyotype and the main characteristics of ES cells. The transgene was found to be stably and ectopically expressed in targeted hESCs. CONCLUSION/SIGNIFICANCE: This is the first targeting of a human physiological gene at a defined locus on the hESC genome. Our findings indicate that the rDNA locus may serve as an ideal harbor for transgenes in hESCs
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector
This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}4.6\;{\rm f}{{{\rm b}}^{-1}}{{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}|\eta |\lt 1.9{{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques
Search for pair-produced long-lived neutral particles decaying to jets in the ATLAS hadronic calorimeter in ppcollisions at √s=8TeV
The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3fb−1of data collected in proton–proton collisions at √s=8TeV. This search is sensitive to long-lived particles that decay to Standard Model particles producing jets at the outer edge of the ATLAS electromagnetic calorimeter or inside the hadronic calorimeter. No significant excess of events is observed. Limits are reported on the product of the scalar boson production cross section times branching ratio into long-lived neutral particles as a function of the proper lifetime of the particles. Limits are reported for boson masses from 100 GeVto 900 GeV, and a long-lived neutral particle mass from 10 GeVto 150 GeV
Transthyretin Aggregation Pathway toward the Formation of Distinct Cytotoxic Oligomers
Characterization of small oligomers formed at an early stage of amyloid formation is critical to
understanding molecular mechanism of pathogenic aggregation process. Here we identifed and
characterized cytotoxic oligomeric intermediates populated during transthyretin (TTR) aggregation
process. Under the amyloid-forming conditions, TTR initially forms a dimer through interactions
between outer strands. The dimers are then associated to form a hexamer with a spherical shape, which
serves as a building block to self-assemble into cytotoxic oligomers. Notably, wild-type (WT) TTR tends
to form linear oligomers, while aTTR variant(G53A) prefers forming annular oligomers with pore-like
structures. Structural analyses of the amyloidogenic intermediates using circular dichroism (CD) and
solid-state NMR revealthatthe dimer and oligomers have a signifcant degree of native-like β-sheet
structures (35–38%), but with more disordered regions (~60%)than those of nativeTTR.TheTTR variant
oligomers are also less structured than WT oligomers. The partially folded nature of the oligomeric
intermediates might be a common structural property of cytotoxic oligomers.The higher fexibility of
the dimer and oligomers may also compensate for the entropic loss due to the oligomerization of the
monomers
Accounting for Ecosystem Alteration Doubles Estimates of Conservation Risk in the Conterminous United States
Previous national and global conservation assessments have relied on habitat conversion data to quantify conservation risk. However, in addition to habitat conversion to crop production or urban uses, ecosystem alteration (e.g., from logging, conversion to plantations, biological invasion, or fire suppression) is a large source of conservation risk. We add data quantifying ecosystem alteration on unconverted lands to arrive at a more accurate depiction of conservation risk for the conterminous United States. We quantify ecosystem alteration using a recent national assessment based on remote sensing of current vegetation compared with modeled reference natural vegetation conditions. Highly altered (but not converted) ecosystems comprise 23% of the conterminous United States, such that the number of critically endangered ecoregions in the United States is 156% higher than when calculated using habitat conversion data alone. Increased attention to natural resource management will be essential to address widespread ecosystem alteration and reduce conservation risk
Research on Teaching and Learning Mathematics at the Tertiary Level:State-of-the-art and Looking Ahead
This topical survey focuses on research in tertiary mathematics education, a field that has experienced considerable growth over the last 10 years. Drawing on the most recent journal publication as well as the latest advances from recent high quality conference proceedings, our review culls out the following five emergent areas of interest: mathematics teaching at the tertiary level; the role of mathematics in other disciplines; textbooks, assessment and students’ studying practices; transition to the tertiary level; and theoretical-methodological advances. We conclude the survey with a discussion of some potential ways forward for future research in this new and rapidly developing domain of inquiry
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