487 research outputs found
Is There a Federal Definitions Power?
Although the Supreme Court decided United States v. Windsor on equal protection grounds, that case also raised important and recurring questions about federal power. In particular, defenders of the Defense of Marriage Act (DOMA) argued that Congress may always define the terms used in federal statutes, even if its definition concerns a matter reserved to the States. As the DOMA illustrates, federal definitions concerning reserved matters that depart from state law may impose significant burdens on state governments and private citizens alike. This Article argues that there is no general, freestanding federal definitions power and that sometimes—as with marriage—federal law must incorporate state law definitions
Vulnerability, Risk, and the Transition to Adulthood
Examines whether poverty and single parenthood influence the likelihood of risk behavior and dropping out among youth and how these behaviors affect the trajectory of connectedness and employment patterns in adulthood. Considers policy implications
Vortex ring refraction at large Froude numbers
We have experimentally studied the impact of an initially planar axisymmetric
vortex ring, incident at an oblique angle, upon a gravity-induced interface
separating two fluids of differing densities. After impact, the vortex ring was
found to exhibit a variety of subsequent trajectories, which we organize
according to both the incidence angle, , and the interface strength,
defined as the ratio of the Atwood and Froude numbers, . For grazing
incidence angles ( deg.) vortices either penetrate or
reflect from the interface, depending on whether the interface is weak or
strong. In some cases, reflected vortices execute damped oscillations before
finally disintegrating. For smaller incidence angles (
deg.) vortices penetrate the interface. When there is a strong interface, these
vortices are observed to curve back up toward the interface. When there is a
weak interface, these vortices are observed to refract downward, away from the
interface. The critical interface strength below which vortex ring refraction
is observed is given by .Comment: 26 pages, 11 figures; Submitted to Physical Review
ExTRUST: Reducing Exploit Stockpiles with a Privacy-Preserving Depletion System for Inter-State Relationships
Cyberspace is a fragile construct threatened by malicious cyber operations of
different actors, with vulnerabilities in IT hardware and software forming the
basis for such activities, thus also posing a threat to global IT security.
Advancements in the field of artificial intelligence accelerate this
development, either with artificial intelligence enabled cyber weapons,
automated cyber defense measures, or artificial intelligence-based threat and
vulnerability detection. Especially state actors, with their long-term
strategic security interests, often stockpile such knowledge of vulnerabilities
and exploits to enable their military or intelligence service cyberspace
operations. While treaties and regulations to limit these developments and to
enhance global IT security by disclosing vulnerabilities are currently being
discussed on the international level, these efforts are hindered by state
concerns about the disclosure of unique knowledge and about giving up tactical
advantages. This leads to a situation where multiple states are likely to
stockpile at least some identical exploits, with technical measures to enable a
depletion process for these stockpiles that preserve state secrecy interests
and consider the special constraints of interacting states as well as the
requirements within such environments being non-existent. This paper proposes
such a privacy-preserving approach that allows multiple state parties to
privately compare their stock of vulnerabilities and exploits to check for
items that occur in multiple stockpiles without revealing them so that their
disclosure can be considered. We call our system ExTRUST and show that it is
scalable and can withstand several attack scenarios. Beyond the
intergovernmental setting, ExTRUST can also be used for other zero-trust use
cases, such as bug-bounty programs.Comment: 16 pages, 3 figures, IEEE Transactions on Technology and Societ
FALLING AS A STRATEGY TO DECREASE KNEE LOADING DURING LANDINGS
Anterior cruciate ligament injuries often occur when individuals land with a single leg. Falling has been suggested as a potential strategy to decrease knee loading during landings. The purpose was to compare knee flexion angles, peak impact forces, and peak knee extension moments among natural landings, soft landings, and falling in forward and vertical landing tasks under single or double leg conditions. Sixteen male and sixteen female participants completed each landing condition, while three-dimensional kinematics and ground reaction forces (GRF) were collected. In the natural landing condition, participants landed as they would in a sport setting. In the soft-landing condition, participants landed as softly as possible with increased knee and hip flexion. In the falling condition, participants initially landed softly and then fell forward or backward onto a mat in the forward and vertical landing tasks, respectively. Knee flexion angles at initial contact and peak knee flexion angles were generally the greatest for the falling, the second greatest for the soft landing, and the least for the natural landing. Peak vertical and posterior GRF and knee extension moments during early landing were generally the least for the falling, the second least for the soft landing, and the greatest for the natural landing. When the sports environment allows, falling appears to be an innovative strategy to decrease knee loading when individuals must land with a single leg and sub-optimal body postures
Perceptions of U.S. and Canadian maple syrup producers toward climate change, its impacts, and potential adaptation measures
The production of maple syrup is an important cultural and economic activity directly related to the climate of northeastern North America. As a result, there are signs that climate change could have negative impacts on maple syrup production in the next decades, particularly for regions located at the southern margins of the sugar maple (Acer saccharum Marsh.) range. The purpose of this survey study is to present the beliefs and opinions of maple syrup producers of Canada (N = 241) and the U.S. (N = 113) on climate change in general, its impacts on sugar maple health and maple syrup production, and potential adaptation measures. Using conditional inference classification trees, we examined how the socio-economic profile of respondents and the geographic location and size of respondents’ sugar bushes shaped the responses of survey participants. While a majority (75%) of respondents are confident that the average temperature on Earth is increasing, less than half (46%) believe that climate change will have negative impacts on maple syrup yield in the next 30 years. Political view was a significant predictor of these results, with respondents at the right right and center-right of the political spectrum being less likely to believe in climate change and less likely to anticipate negative effects of climate change on maple syrup production. In addition, 77% of the participants indicated an interest in adopting adaptation strategies if those could increase maple syrup production. This interest was greater for respondents using vacuum tubing for sap collection than other collection methods. However, for many respondents (particularly in Canada), lack of information was identified as a constraint limiting adaptation to climate change.SL and AP were partly funded by the CICan Career-Launcher Internship program. AA was supported by Spanish Government through the Juan de la Cierva fellowship program (IJCI- 2016-30049)
Functional analysis of Plasmodium falciparum subpopulations associated with artemisinin resistance in Cambodia
Background: Plasmodium falciparum malaria is one of the most widespread parasitic infections in humans and remains a leading global health concern. Malaria elimination efforts are threatened by the emergence and spread of resistance to artemisinin-based combination therapy, the first-line treatment of malaria. Promising molecular markers and pathways associated with artemisinin drug resistance have been identified, but the underlying molecular mechanisms of resistance remains unknown. The genomic data from early period of emergence of artemisinin resistance (2008–2011) was evaluated, with aim to define k13 associated genetic background in Cambodia, the country identified as epicentre of anti-malarial drug resistance, through characterization of 167 parasite isolates using a panel of 21,257 SNPs. Results: Eight subpopulations were identified suggesting a process of acquisition of artemisinin resistance consistent with an emergence-selection-diffusion model, supported by the shifting balance theory. Identification of population specific mutations facilitated the characterization of a core set of 57 background genes associated with artemisinin resistance and associated pathways. The analysis indicates that the background of artemisinin resistance was not acquired after drug pressure, rather is the result of fixation followed by selection on the daughter subpopulations derived from the ancestral population. Conclusions: Functional analysis of artemisinin resistance subpopulations illustrates the strong interplay between ubiquitination and cell division or differentiation in artemisinin resistant parasites. The relationship of these pathways with the P. falciparum resistant subpopulation and presence of drug resistance markers in addition to k13, highlights the major role of admixed parasite population in the diffusion of artemisinin resistant background. The diffusion of resistant genes in the Cambodian admixed population after selection resulted from mating of gametocytes of sensitive and resistant parasite populations. (Résumé d'auteur
Singularity in the boundary resistance between superfluid He and a solid surface
We report new measurements in four cells of the thermal boundary resistance
between copper and He below but near the superfluid-transition
temperature . For fits of to the data yielded ,
whereas a fit to theoretical values based on the renormalization-group theory
yielded . Alternatively, a good fit of the theory to the data could
be obtained if the {\it amplitude} of the prediction was reduced by a factor
close to two. The results raise the question whether the boundary conditions
used in the theory should be modified.Comment: 4 pages, 4 figures, revte
The Malta cistern mapping project : expedition II
This paper documents the second of two
archeological expeditions that employed several
underwater robot mapping and localization
techniques. The goal of this project is to explore
and map ancient cisterns located on the islands of
Malta and Gozo. Dating back to 300 B.C., the
cisterns of interest acted as water storage systems
for fortresses, private homes, and churches. They
often consisted of several connected chambers,
still containing water. A Remotely Operated
Vehicle (ROV), was deployed into cisterns to
obtain video and sonar images. Using a variety of
sonar based mapping techniques, two-dimensional
maps of 18 different cisterns were created.peer-reviewe
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