1,319 research outputs found
Self-Focusing Dynamics of Coupled Optical Beams
We theoretically and experimentally investigate the mutual collapse dynamics
of two spatially separated optical beams in a Kerr medium. Depending on the
initial power, beam separation, and the relative phase, we observe repulsion or
attraction, which in the latter case reveals a sharp transition to a single
collapsing beam. This transition to fusion of the beams is accompanied by an
increase in the collapse distance, indicating the effect of the nonlinear
coupling on the individual collapse dynamics. Our results shed light on the
basic nonlinear interaction between self-focused beams and provide a mechanism
to control the collapse dynamics of such beams.Comment: 5 pages, 4 figure
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Draft Genome Sequences of Four Saccharibacter sp. Strains Isolated from Native Bees.
The genus Saccharibacter is currently understudied, with only one described species, Saccharibacter floricola, isolated from a flower. In an effort to better understand the microbes that come in contact with native bee pollinators, we isolated and sequenced four additional strains of Saccharibacter from native bees in the genera Melissodes and Anthophora These genomes range in size from 2,104,494 to 2,316,791 bp (mean, 2,246,664 bp) and contain between 1,860 and 2,167 (mean, 2,060) protein-coding genes
Net neutrality discourses: comparing advocacy and regulatory arguments in the United States and the United Kingdom
Telecommunications policy issues rarely make news, much less mobilize thousands of people. Yet this has been occurring in the United States around efforts to introduce "Net neutrality" regulation. A similar grassroots mobilization has not developed in the United Kingdom or elsewhere in Europe. We develop a comparative analysis of U.S. and UK Net neutrality debates with an eye toward identifying the arguments for and against regulation, how those arguments differ between the countries, and what the implications of those differences are for the Internet. Drawing on mass media, advocacy, and regulatory discourses, we find that local regulatory precedents as well as cultural factors contribute to both agenda setting and framing of Net neutrality. The differences between national discourses provide a way to understand both the structural differences between regulatory cultures and the substantive differences between policy interpretations, both of which must be reconciled for the Internet to continue to thrive as a global medium
Net neutrality discourses: comparing advocacy and regulatory arguments in the United States and the United Kingdom
Telecommunications policy issues rarely make news, much less mobilize thousands of people. Yet this has been occurring in the United States around efforts to introduce "Net neutrality" regulation. A similar grassroots mobilization has not developed in the United Kingdom or elsewhere in Europe. We develop a comparative analysis of U.S. and UK Net neutrality debates with an eye toward identifying the arguments for and against regulation, how those arguments differ between the countries, and what the implications of those differences are for the Internet. Drawing on mass media, advocacy, and regulatory discourses, we find that local regulatory precedents as well as cultural factors contribute to both agenda setting and framing of Net neutrality. The differences between national discourses provide a way to understand both the structural differences between regulatory cultures and the substantive differences between policy interpretations, both of which must be reconciled for the Internet to continue to thrive as a global medium
The International-Trade Network: Gravity Equations and Topological Properties
This paper begins to explore the determinants of the topological properties
of the international - trade network (ITN). We fit bilateral-trade flows using
a standard gravity equation to build a "residual" ITN where trade-link weights
are depurated from geographical distance, size, border effects, trade
agreements, and so on. We then compare the topological properties of the
original and residual ITNs. We find that the residual ITN displays, unlike the
original one, marked signatures of a complex system, and is characterized by a
very different topological architecture. Whereas the original ITN is
geographically clustered and organized around a few large-sized hubs, the
residual ITN displays many small-sized but trade-oriented countries that,
independently of their geographical position, either play the role of local
hubs or attract large and rich countries in relatively complex
trade-interaction patterns
Older cancer patients during the COVID-19 epidemic: Practice proposal of the international geriatric radiotherapy group
The coronavirus disease 19 (COVID-19) pandemic is unprecedented as it reached all countries in the world within a record short period of time. Even though COVID-19 infection may be just severe in any adults, older adults (65-year-old or older) may experience a higher mortality rate. Among those affected, cancer patients may have a worse outcome compared to the general population because of their depressed immune status. As the health resources of most countries are limited, clinicians may face painful decisions about which patients to save if they require artificial ventilation. Cancer patients, especially the older ones, may be denied supportive care because of their shorter life expectancy. Thus, special considerations should be taken to prevent infection of older cancer patients and to provide them with adequate social support during their cancer treatment. The following proposal was reached: (1) Education of health care providers about the special needs of older cancer patients and their risks of infection. (2) Special consideration such as surgical masks and separate scheduling should be made to protect them from being infected. (3) Social services such as patient navigators should be provided to ensure adequate medical supply, food, and daily transportation to cancer centers. (4) Close monitoring through phone calls, telecommunication to ensure social distancing and psychological support from patient family to prevent anxiety and depression. (5) Shorter course of radiotherapy by use of hypofractionation where possible to decrease the needs for daily transportation and exposure to infection. (6) Enrollment of older cancer patients in clinical trials for potential antiviral medications if infection does occur. (7) Home health care telemedicine may be an effective strategy for older cancer patients with COVID-19 infection to avoid hospital admission when health care resources become restricted. (8) For selected patients, immunotherapy and targeted therapy may become the systemic therapy of choice for older cancer patients and need to be tested in clinical trials
Sensitivity of a tonne-scale NEXT detector for neutrinoless double beta decay searches
The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless
double-beta decay of Xe-136 using high-pressure xenon gas TPCs with
electroluminescent amplification. A scaled-up version of this technology with
about 1 tonne of enriched xenon could reach in less than 5 years of operation a
sensitivity to the half-life of neutrinoless double-beta decay decay better
than 1E27 years, improving the current limits by at least one order of
magnitude. This prediction is based on a well-understood background model
dominated by radiogenic sources. The detector concept presented here represents
a first step on a compelling path towards sensitivity to the parameter space
defined by the inverted ordering of neutrino masses, and beyond.Comment: 22 pages, 11 figure
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