533 research outputs found
Perceptions of the past in the post-Soviet space
Honing in on how citizens in the former Soviet Union find themselves in an information competition over their own past, this paper explores whether and why ordinary people’s perceptions of historical events and figures in their country’s past are in line with a Russian-promoted narrative that highlights World War II – known as the “Great Patriotic War” in Russia and some former Soviet states – as a glorious Soviet victory and Stalin as a great leader. We draw on comparative survey data across six states and one de facto state in 2019–2020 to examine whether geopolitical or cultural proximity to Russia is associated with a more favourable view on a Russian-promoted narrative about the past. We find that closer geopolitical proximity to Russia is associated with perceiving the past in line with the Russian-promoted narrative, though the findings are less consistent when it comes to measures for closer cultural proximity
A CRISPR-Cas9 sex-ratio distortion system for genetic control.
Genetic control aims to reduce the ability of insect pest populations to cause harm via the release of modified insects. One strategy is to bias the reproductive sex ratio towards males so that a population decreases in size or is eliminated altogether due to a lack of females. We have shown previously that sex ratio distortion can be generated synthetically in the main human malaria vector Anopheles gambiae, by selectively destroying the X-chromosome during spermatogenesis, through the activity of a naturally-occurring endonuclease that targets a repetitive rDNA sequence highly-conserved in a wide range of organisms. Here we describe a CRISPR-Cas9 sex distortion system that targets ribosomal sequences restricted to the member species of the Anopheles gambiae complex. Expression of Cas9 during spermatogenesis resulted in RNA-guided shredding of the X-chromosome during male meiosis and produced extreme male bias among progeny in the absence of any significant reduction in fertility. The flexibility of CRISPR-Cas9 combined with the availability of genomic data for a range of insects renders this strategy broadly applicable for the species-specific control of any pest or vector species with an XY sex-determination system by targeting sequences exclusive to the female sex chromosome
Holography for the Lorentz Group Racah Coefficients
A known realization of the Lorentz group Racah coefficients is given by an
integral of a product of 6 ``propagators'' over 4 copies of the hyperbolic
space. These are ``bulk-to-bulk'' propagators in that they are functions of two
points in the hyperbolic space. It is known that the bulk-to-bulk propagator
can be constructed out of two bulk-to-boundary ones. We point out that there is
another way to obtain the same object. Namely, one can use two bulk-to-boundary
and one boundary-to-boundary propagator. Starting from this construction and
carrying out the bulk integrals we obtain a realization of the Racah
coefficients that is ``holographic'' in the sense that it only involves
boundary objects. This holographic realization admits a geometric
interpretation in terms of an ``extended'' tetrahedron.Comment: 12 pages, 2 figures; v2: minor changes; v3: "extended" tetrahedron
interpretation adde
Penrose Limits and Spacetime Singularities
We give a covariant characterisation of the Penrose plane wave limit: the
plane wave profile matrix is the restriction of the null geodesic
deviation matrix (curvature tensor) of the original spacetime metric to the
null geodesic, evaluated in a comoving frame. We also consider the Penrose
limits of spacetime singularities and show that for a large class of black
hole, cosmological and null singularities (of Szekeres-Iyer ``power-law
type''), including those of the FRW and Schwarzschild metrics, the result is a
singular homogeneous plane wave with profile , the scale
invariance of the latter reflecting the power-law behaviour of the
singularities.Comment: 9 pages, LaTeX2e; v2: additional references and cosmetic correction
The compression type of coronary artery motion in patients with ST-segment elevation acute myocardial infarction and normal controls: a case-control study
<p>Abstract</p> <p>Background</p> <p>Prediction of the location of culprit lesions responsible for ST-segment elevation myocardial infarctions may allow for prevention of these events. A retrospective analysis of coronary artery motion (CAM) was performed on coronary angiograms of 20 patients who subsequently had ST-segment elevation myocardial infarction treated by primary or rescue angioplasty and an equal number of age and sex matched controls with normal angiograms.</p> <p>Findings</p> <p>There was no statistically significant difference between the frequency of CAM types of the ST-segment elevation acute myocardial infarction and control patients (p = 0.97). The compression type of CAM is more frequent in the proximal and mid segments of all three coronary arteries. No statistically significant difference was found when the frequency of the compression type of CAM was compared between the ST-segment elevation acute myocardial infarction and control patients for the individual coronary artery segments (p = 0.59).</p> <p>Conclusion</p> <p>The proportion of the compression type of coronary artery motion for individual artery segments is not different between patients who have subsequent ST-segment elevation myocardial infarctions and normal controls.</p
On the Boundary Dynamics of Chern-Simons Gravity
We study Chern-Simons theory with a complex G_C or a real G x G gauge group
on a manifold with boundary - this includes Lorentzian and Euclidean (anti-) de
Sitter (E/A)dS gravity for G=SU(2) or G=SL(2,R). We show that there is a
canonical choice of boundary conditions that leads to an unambiguous, fully
covariant and gauge invariant, off-shell derivation of the boundary action - a
G_C/G or G WZW model, coupled in a gauge invariant way to the boundary value of
the gauge field. In particular, for (E/A)dS gravity, the boundary action is a
WZW model with target space (E/A)dS_3, reminiscent of a worldsheet for
worldsheet mechanism. We discuss in some detail the properties of the boundary
theories that arise and we confront our results with various related
constructions in the literature.Comment: 22 pages, LaTeX2e, v2: JHEP3.cls, references and a footnote adde
The effect of multimorbidity patterns and the impact of comorbid anxiety and depression on primary health service use: the Men Androgen Inflammation Lifestyle Environment and Stress (MAILES) study
This study sought to determine patterns of multimorbidity and quantify their impact on use of primary health services in the presence and absence of anxiety and depression among a cohort of urban community-dwelling men in Australia. The analytic sample consisted of men (n = 2039; age 38-85) from the follow-up wave of a prospective cohort study of all participants of the Florey Adelaide Male Ageing Study (FAMAS; Stage 2 [2007-2010]) and age-matched men from the North-West Adelaide Health Study (NWAHS; Stage 3 [2008-2010]). Self-reported data and linkage with a national universal health coverage scheme (Medicare) provided information on the prevalence of eight chronic conditions and health service utilization information (including annual GP visits). Obesity and cardiovascular disease (CVD) were associated with the highest number of comorbid conditions. Two nonrandom multimorbidity "clusters" emerged: "CVD, Obesity, Diabetes" and "CVD, Obesity, Osteoarthritis." Participants with conditions comorbid with CVD were more likely to have 10 or more annual GP visits, compared to multimorbidity involving other conditions. In comparison to participants without CVD, the presence of CVD increased the chance of having 10 or more annual GP visits (adjusted risk ratio: 3.7; 95% CI [2.8, 4.8]). When CVD was comorbid with anxiety and depression, having 10 or more annual GP visits was more common (adjusted risk ratio: 1.8; 95% CI [1.2, 2.5]). Multimorbidity patterns involving CVD, especially for multimorbidity that includes CVD with comorbid anxiety and depression, should be considered in developing clinical trials to better inform medical decision-making and care for patients with CVD and comorbid conditions.Shu-Kay Ng, Sean A. Martin, Robert J. Adams, Peter O’Loughlin, and Gary A. Witter
Black Hole Remnants and the Information Puzzle
Magnetically charged dilatonic black holes have a perturbatively infinite
ground state degeneracy associated with an infinite volume throat region of the
geometry. A simple argument based on causality is given that these states do
not have a description as ordinary massive particles in a low-energy effective
field theory. Pair production of magnetic black holes in a weak magnetic field
is estimated in a weakly-coupled semiclassical expansion about an instanton and
found to be finite, despite the infinite degeneracy of states. This suggests
that these states may store the information apparently lost in black hole
scattering processes.Comment: 16 pages, revision has 5 figures uuencode
- …