3,556 research outputs found
Continuous Generation and Stabilization of Mesoscopic Field Superposition States in a Quantum Circuit
While dissipation is widely considered as being harmful for quantum
coherence, it can, when properly engineered, lead to the stabilization of
non-trivial pure quantum states. We propose a scheme for continuous generation
and stabilization of Schr\"{o}dinger cat states in a cavity using dissipation
engineering. We first generate non-classical photon states with definite parity
by means of a two-photon drive and dissipation, and then stabilize these
transient states against single-photon decay. The single-photon stabilization
is autonomous, and is implemented through a second engineered bath, which
exploits the photon number dependent frequency-splitting due to Kerr
interactions in the strongly dispersive regime of circuit QED. Starting with
the Hamiltonian of the baths plus cavity, we derive an effective model of only
the cavity photon states along with analytic expressions for relevant physical
quantities, such as the stabilization rate. The deterministic generation of
such cat states is one of the key ingredients in performing universal quantum
computation.Comment: 9 pages, 6 figure
Multimorbidity due to novel pathogenic variants in the WFS1/RP1/NOD2 genes: autosomal dominant congenital lamellar cataract, retinitis pigmentosa and Crohnâs disease in a British family
Background: A five generation family has been analysed by whole exome sequencing (WES) for genetic associations with the multimorbidities of congenital cataract (CC), retinitis pigmentosa (RP) and Crohnâs disease (CD). //
Methods: WES was performed for unaffected and affected individuals within the family pedigree followed by bioinformatic analyses of these data to identify disease-causing variants with damaging pathogenicity scores. //
Results: A novel pathogenic missense variant in WFS1: c.1897G>C; p.V633L, a novel pathogenic nonsense variant in RP1: c.6344T>G; p.L2115* and a predicted pathogenic missense variant in NOD2: c.2104C>T; p.R702W are reported. The three variants cosegregated with the phenotypic combinations of autosomal dominant CC, RP and CD within individual family members. //
Conclusions: Here, we report multimorbidity in a family pedigree listed on a CC register, which broadens the spectrum of potential cataract associated genes to include both RP1 and NOD2
Using a model of group psychotherapy to support social research on sensitive topics
This article describes the exploratory use of professional therapeutic support by social researchers working on a sensitive topic. Talking to recently bereaved parents about the financial implications of their child's death was expected to be demanding work, and the research design included access to an independent psychotherapeutic service. Using this kind of professional support is rare within the general social research community, and it is useful to reflect on the process. There are likely to be implications for collection and interpretation of data, research output and the role and experience of the therapist. Here, the primary focus is the potential impact on researcher well-being
The genetic landscape of crystallins in congenital cataract
Background: The crystalline lens is mainly composed of a large family of soluble proteins called the crystallins, which are responsible for its development, growth, transparency and refractive index. Disease-causing sequence variants in the crystallins are responsible for nearly 50% of all non-syndromic inherited congenital cataracts, as well as causing cataract associated with other diseases, including myopathies. To date, more than 300 crystallin sequence variants causing cataract have been identified. Methods: Here we aimed to identify the genetic basis of disease in five multi-generation British families and five sporadic cases with autosomal dominant congenital cataract using whole exome sequencing, with identified variants validated using Sanger sequencing. Following bioinformatics analysis, rare or novel variants with a moderate to damaging pathogenicity score, were filtered out and tested for segregation within the families. Results: We have identified 10 different heterozygous crystallin variants. Five recurrent variants were found: family-A, with a missense variant (c.145C>T; p.R49C) in CRYAA associated with nuclear cataract; family-B, with a deletion in CRYBA1 (c.272delGAG; p.G91del) associated with nuclear cataract; and family-C, with a truncating variant in CRYGD (c.470G>A; W157*) causing a lamellar phenotype; individuals I and J had variants in CRYGC (c.13A>C; T5P) and in CRYGD (c.418C>T; R140*) causing unspecified congenital cataract and nuclear cataract, respectively. Five novel disease-causing variants were also identified: family D harboured a variant in CRYGC (c.179delG; R60Qfs*) responsible for a nuclear phenotype; family E, harboured a variant in CRYBB1 (c.656G>A; W219*) associated with lamellar cataract; individual F had a variant in CRYGD (c.392G>A; W131*) associated with nuclear cataract; and individuals G and H had variants in CRYAA (c.454delGCC; A152del) and in CRYBB1 (c.618C>A; Y206*) respectively, associated with unspecified congenital cataract. All novel variants were predicted to be pathogenic and to be moderately or highly damaging. Conclusions: We report five novel variants and five known variants. Some are rare variants that have been reported previously in small ethnic groups but here we extend this to the wider population and record a broader phenotypic spectrum for these variants
Instability of metal-insulator transition against thermal cycling in phase separated Cr-doped manganites
We show that metal-insulator transition in Pr0.5Ca0.5Mn1-xCrxO3 (x =
0.015-0.025) is unstable against thermal cycling. Insulator-metal transition
shifts down and low temperature resistivity increases each time when the sample
is cycled between a starting temperature TS and a final temperature TF. The
effect is dramatic lower is x. Insulator-metal transition in x = 0.015 can be
completely destroyed by thermal cycling in absence of magnetic field as well as
under H = 2 T. Magnetic measurements suggest that ferromagnetic phase fraction
decreases with thermal cycling. We suggest that increase in strains in
ferromagnetic- charge ordered interface could be a possible origin of the
observed effect.Comment: 14 pages, 5 figures and 2 tables (revised
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Relationship between latent and rebound viruses in a clinical trial of anti-HIV-1 antibody 3BNC117.
A clinical trial was performed to evaluate 3BNC117, a potent anti-HIV-1 antibody, in infected individuals during suppressive antiretroviral therapy and subsequent analytical treatment interruption (ATI). The circulating reservoir was evaluated by quantitative and qualitative viral outgrowth assay (Q2VOA) at entry and after 6 mo. There were no significant quantitative changes in the size of the reservoir before ATI, and the composition of circulating reservoir clones varied in a manner that did not correlate with 3BNC117 sensitivity. 3BNC117 binding site amino acid variants found in rebound viruses preexisted in the latent reservoir. However, only 3 of 217 rebound viruses were identical to 868 latent viruses isolated by Q2VOA and near full-length sequencing. Instead, 63% of the rebound viruses appeared to be recombinants, even in individuals with 3BNC117-resistant reservoir viruses. In conclusion, viruses emerging during ATI in individuals treated with 3BNC117 are not the dominant species found in the circulating latent reservoir, but frequently appear to represent recombinants of latent viruses
Planet Migration and Disk Destruction due to Magneto-Centrifugal Stellar Winds
This paper investigates the influence of magneto-centrifugally driven or
simply magnetic winds of rapidly-rotating, strongly-magnetized T Tauri stars in
causing the inward or outward migration of close-in giant planets. The
azimuthal ram pressure of the magnetized wind acting on the planet tends to
increase the planet's angular momentum and cause outward migration if the
star's rotation period is less than the planet's orbital period . In
the opposite case, , the planet migrates inward. Thus, planets
orbiting at distances larger (smaller) than
tend to be pushed outward (inward), where is the rotation period of the
star assumed to have the mass of the sun. The magnetic winds are likely to
occur in T Tauri stars where the thermal speed of the gas close to the star is
small, where the star's magnetic field is strong, and where the star rotates
rapidly. The time-scale for appreciable radial motion of the planet is
estimated as Myr. A sufficiently massive close-in planet may
cause tidal locking and once this happens the radial migration due to the
magnetic wind ceases. The magnetic winds are expected to be important for
planet migration for the case of a multipolar magnetic field rather than a
dipole field where the wind is directed away from the equatorial plane and
where a magnetospheric cavity forms. The influence of the magnetic wind in
eroding and eventually destroying the accretion disk is analyzed. A momentum
integral is derived for the turbulent wind/disk boundary layer and this is used
to estimate the disk erosion time-scale as Myr, with the lower
value favored.Comment: 8 pages, 6 figure
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