2,284 research outputs found
A Study Of The Costs Of Cloud-Based Website Parallel Archiving System
Parallel Archiving System supports web applications that are periodically renewed, frequently changed in design and supporting technologies, and are required to keep the previous periods’ applications operational in parallel with the current period application to form an easy-to-access archive for historical data. The system implements each period’s application with a virtual machine to preserve the technologies and deploys it in a cloud platform. This paper studies the costs of a cloud-based Parallel Archiving System that include the cost of virtual machine, database server, data storage, business transactions and website traffic. This study will help a manager in determining how many of previous periods’ applications an organization can afford to run for a given budget
A gradual separation from the world: a qualitative exploration of existential loneliness in old age
This study sought to explore qualitatively experiences of existential loneliness (EL) in 80 older people living in retirement communities across the United Kingdom and Australia. Qualitative semi-structured interviews permitted in-depth exploration of issues such as biographical narrative, close relationships, loss, feelings of loneliness and retirement living. It was our intention to conduct a large-scale, deep-listening exercise that would provide further clues about EL in older people and the circumstances that give rise to such feelings. Data provided rich insight into older people's inner lives. Core themes identified loss of close attachments, lack of physical touch and intimacy, deterioration of health and body, and lack of an emotional language through which to express EL as central to older people's experiences. Furthermore, there was a suggestion that the move to retirement living was for many people inextricably connected to their experience of EL. Our data further support and extend the notion that EL can be thought of as a gradual sense of separation from the world and that ageing intensifies a myriad of social, emotional and physical circumstances that prompt its emergence. This sense of existential isolation need not be thought of as exclusive to those experiencing extreme frailty or who face death imminently – our data pointed to a clear and gradual emergence of EL throughout later lif
Pairs of disjoint matchings and related classes of graphs
For a finite graph , we study the maximum -edge colorable subgraph
problem and a related ratio , where is the
matching number of , and is the size of the largest matching in any
pair of disjoint matchings maximizing (equivalently,
forming a maximum -edge colorable subgraph). Previously, it was shown that
, and the class of graphs
achieving was completely characterized. We show here that any
rational number between and can be achieved by a connected
graph. Furthermore, we prove that every graph with ratio less than must
admit special subgraphs
Numerical Simulation of Chemical Spills and Assessment of Environmental Impacts
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Recycling paper to recarbonise soil
Soil organic carbon can be increased through sympathetic land management and/or directly by incorporating carbon rich amendments. Herein, a field experiment amended paper crumble (PC) to soil at a normal deployment rate of 50 t ha−1, and at higher rates up to 200 t ha−1. The nominal 50 t ha−1 PC amendment resulted a mean increase in soil carbon of 12.5 g kg−1. Using a modified ROTH-C carbon fate model, the long-term (50 years) carbon storage potential of a 50 t ha−1 PC amendment was determined to be 0.36 tC ha−1. Modelling a rotational (4 yearly) 50 t ha−1 PC amendment indicated 6.65 tC ha−1 uplift would accrue after 50 years. Contextualised for the average farm in the East of England (~120 ha, with 79 % as arable), PC derived increases in SOC would be equivalent to 2310 t CO2e. These results support the use of PC to deliver significant levels of soil recarbonisation. Beyond carbon, PC was observed to influence other soil properties. Benefits observed included, decreased bulk density, increased water holding capacity, and increased cation exchange capacity. While PC amendment did not significantly increase wheat (Triticum aestivum) crop yield, manifold benefits in terms of increased SOC, long-term carbon storage potential, and improved soil quality sustains PC as a beneficial soil conditioner
Extreme genetic fragility of the HIV-1 capsid
Genetic robustness, or fragility, is defined as the ability, or lack thereof, of a biological entity to maintain function in the face of mutations. Viruses that replicate via RNA intermediates exhibit high mutation rates, and robustness should be particularly advantageous to them. The capsid (CA) domain of the HIV-1 Gag protein is under strong pressure to conserve functional roles in viral assembly, maturation, uncoating, and nuclear import. However, CA is also under strong immunological pressure to diversify. Therefore, it would be particularly advantageous for CA to evolve genetic robustness. To measure the genetic robustness of HIV-1 CA, we generated a library of single amino acid substitution mutants, encompassing almost half the residues in CA. Strikingly, we found HIV-1 CA to be the most genetically fragile protein that has been analyzed using such an approach, with 70% of mutations yielding replication-defective viruses. Although CA participates in several steps in HIV-1 replication, analysis of conditionally (temperature sensitive) and constitutively non-viable mutants revealed that the biological basis for its genetic fragility was primarily the need to coordinate the accurate and efficient assembly of mature virions. All mutations that exist in naturally occurring HIV-1 subtype B populations at a frequency >3%, and were also present in the mutant library, had fitness levels that were >40% of WT. However, a substantial fraction of mutations with high fitness did not occur in natural populations, suggesting another form of selection pressure limiting variation in vivo. Additionally, known protective CTL epitopes occurred preferentially in domains of the HIV-1 CA that were even more genetically fragile than HIV-1 CA as a whole. The extreme genetic fragility of HIV-1 CA may be one reason why cell-mediated immune responses to Gag correlate with better prognosis in HIV-1 infection, and suggests that CA is a good target for therapy and vaccination strategies
Ready Both to Your and to My Hands: Mapping the Action Space of Others
To date, mutual interaction between action and perception has been investigated mainly by focusing on single individuals. However, we perceive affording objects and acts upon them in a surrounding world inhabited by other perceiving and acting bodies. Thus, the issue arises as to whether our action-oriented object perception might be modulated by the presence of another potential actor. To tackle this issue we used the spatial alignment effect paradigm and systematically examined this effect when a visually presented handled object was located close either to the perceiver or to another individual (a virtual avatar). We found that the spatial alignment effect occurred whenever the object was presented within the reaching space of a potential actor, regardless of whether it was the participant's own or the other's reaching space. These findings show that objects may afford a suitable motor act when they are ready not only to our own hand but also, and most importantly, to the other's hand. Our proposal is that this effect is likely to be due to a mapping of our own and the other's reaching space and we posit that such mapping could play a critical role in joining our own and the other's action
Photonic chip-based low noise microwave oscillator
Numerous modern technologies are reliant on the low-phase noise and exquisite
timing stability of microwave signals. Substantial progress has been made in
the field of microwave photonics, whereby low noise microwave signals are
generated by the down-conversion of ultra-stable optical references using a
frequency comb. Such systems, however, are constructed with bulk or fiber
optics and are difficult to further reduce in size and power consumption. Our
work addresses this challenge by leveraging advances in integrated photonics to
demonstrate low-noise microwave generation via two-point optical frequency
division. Narrow linewidth self-injection locked integrated lasers are
stabilized to a miniature Fabry-P\'{e}rot cavity, and the frequency gap between
the lasers is divided with an efficient dark-soliton frequency comb. The
stabilized output of the microcomb is photodetected to produce a microwave
signal at 20 GHz with phase noise of -96 dBc/Hz at 100 Hz offset frequency that
decreases to -135 dBc/Hz at 10 kHz offset--values which are unprecedented for
an integrated photonic system. All photonic components can be heterogeneously
integrated on a single chip, providing a significant advance for the
application of photonics to high-precision navigation, communication and timing
systems
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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