Unparticle inspired corrections to the Gravitational Quantum Well

We consider unparticle inspired corrections of the type ${(\frac{R_{G}}{r})}^\beta$ to the Newtonian potential in the context of the gravitational quantum well. The new energy spectrum is computed and bounds on the parameters of these corrections are obtained from the knowledge of the energy eigenvalues of the gravitational quantum well as measured by the GRANIT experiment.Comment: Revtex4 file, 4 pages, 2 figures and 1 table. Version to match the one published at Physical Review

The rad18 Gene of Schizosaccharomyces pombe Defines a New Subgroup of the SMC Superfamily Involved in DNA Repair

The rad18 mutant of Schizosaccharomyces pombe is very sensitive to killing by both UV and ¿ radiation. We have cloned and sequenced the rad18 gene and isolated and sequenced its homolog from Saccharomyces cerevisiae, designated RHC18. The predicted Rad18 protein has all the structural properties characteristic of the SMC family of proteins, suggesting a motor function- the first implicated in DNA repair. Gene deletion shows that both rad18 and RHC18 are essential for proliferation. Genetic and biochemical analyses suggest that the product of the rad18 gene acts in a DNA repair pathway for removal of UV-induced DNA damage that is distinct from classical nucleotide excision repair. This second repair pathway involves the products of the rhp51 gene (the homolog of the RAD51 gene of S. cerevisiae) and the rad2 gene

Evidence of Novel Quasiparticles in a Strongly Interacting Two-Dimensional Electron System: Giant Thermopower and Metallic Behaviour

We report thermopower ($S$) and electrical resistivity ($\rho_{2DES}$) measurements in low-density (10$^{14}$ m$^{-2}$), mesoscopic two-dimensional electron systems (2DESs) in GaAs/AlGaAs heterostructures at sub-Kelvin temperatures. We observe at temperatures $\lesssim$ 0.7 K a linearly growing $S$ as a function of temperature indicating metal-like behaviour. Interestingly this metallicity is not Drude-like, showing several unusual characteristics: i) the magnitude of $S$ exceeds the Mott prediction valid for non-interacting metallic 2DESs at similar carrier densities by over two orders of magnitude; and ii) $\rho_{2DES}$ in this regime is two orders of magnitude greater than the quantum of resistance $h/e^2$ and shows very little temperature-dependence. We provide evidence suggesting that these observations arise due to the formation of novel quasiparticles in the 2DES that are not electron-like. Finally, $\rho_{2DES}$ and $S$ show an intriguing decoupling in their density-dependence, the latter showing striking oscillations and even sign changes that are completely absent in the resistivity.Comment: QFS2012 Conference proceedings, Journal of Low Temperature Physics, accepted (figure and discussion added upon referee suggestions

Top-down social modulation of interpersonal observation-execution.

Cyclical upper limb movement can involuntarily deviate from its primary movement axis when the performer concurrently observes incongruent biological motion (i.e. interpersonal observation-execution). The current study examined the social modulation of such involuntary motor interference using a protocol that reflected everyday social interactions encountered in a naturalistic social setting. Eighteen participants executed cyclical horizontal arm movements during the observation of horizontal (congruent) or curvilinear (incongruent) biological motion. Both prior to, and during the interpersonal observation-execution task, participants also received a series of social words designed to prime a pro-social or anti-social attitude. The results showed greater orthogonal movement deviation, and thus interference, for the curvilinear compared to horizontal stimuli. Importantly, and opposite to most of the previous findings from work on automatic imitation and mimicry, there was a greater interference effect for the anti-social compared to pro-social prime condition. These findings demonstrate the importance of interpreting the context of social primes, and strongly support predictions of a comparison between the prime construct and the self-concept/-schema and the top-down response modulation of social incentives

Raltegravir-intensified initial antiretroviral therapy in advanced HIV in Africa: a randomized controlled trial

BACKGROUND: In sub-Saharan Africa, severely immunocompromised HIV-infected individuals have high mortality (10%) shortly after starting antiretroviral therapy (ART). This group also have the greatest risk of morbidity and mortality associated with immune reconstitution inflammatory syndrome (IRIS), a paradoxical response to successful ART. Integrase inhibitors lead to significantly more rapid declines in HIV viral load (VL) than all other ART classes. We hypothesised that intensifying standard triple-drug ART with the integrase inhibitor, raltegravir, would reduce HIV VL faster, and hence reduce early mortality, although this strategy could also risk more IRIS events. METHODS AND FINDINGS: In a 2x2x2 factorial open-label parallel-group trial, treatment-naïve HIV-infected adults, adolescents and children >5 years with CD4 0.7), and despite significantly greater VL suppression with raltegravir-intensified-ART at 4-weeks (343/836 (41.0%) vs 113/841 (13.4%) standard-ART, p<0.001) and 12-weeks (567/789 (71.9%) vs 415/803 (51.7%) standard-ART, p<0.001). Through 48-weeks there was no evidence of differences in mortality (aHR=0.98 (95%CI 0.76-1.28) p=0.91); serious (aHR=0.99 (0.81-1.21) p=0.88), grade-4 (aHR=0.88 (0.71-1.09) p=0.29) or ART-modifying (aHR=0.90 (0.63-1.27) p=0.54) adverse events (the latter occurring in occurring in 59 (6.5%) raltegravir-intensified-ART vs 66 (7.3%) standard-ART); in events judged compatible with IRIS (occurring in 89 (9.9%) raltegravir-intensified-ART vs 86 (9.5%) standard-ART, p=0.79) or hospitalizations (aHR=0.94 (95%CI 0.76-1.17) p=0.59). At 12 weeks, one and two raltegravir-intensified participants had predicted intermediate-level and high-level raltegravir resistance respectively. At 48 weeks, the NRTI mutation K219E/Q (p=0.004), and the NNRTI mutations K101E/P (p=0.03) and P225H (p=0.007), were less common in raltegravir-intensified-ART, with weak evidence of less intermediate or high-level resistance to tenofovir (p=0.06), abacavir (p=0.08) and rilpivirine (p=0.07). Limitations were limited clinical, radiological and/or microbiological information for some participants, reflecting available services at the centres, and lack of baseline genotypes. CONCLUSIONS: Although 12-weeks raltegravir-intensification was well-tolerated and reduced HIV viraemia significantly faster than standard triple-drug ART during the time of greatest risk for early death, this strategy did not reduce mortality or clinical events, and is not warranted. There was no excess of IRIS-compatible events, suggesting integrase inhibitors can be used safely as part of standard triple-drug first-line therapy in severely immuno-compromised individuals

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The role of teachers in editing and authoring units of learning using IMS Learning Design

The UNFOLD project, funded by the European Commission, runs a Community of Practice for Teachers and Learning Providers that has examined the way in which teachers can work with the IMS Learning Design Specification. The results of this work are presented. Relevant aspects of the specification are discussed, in particular the design process as it is set out in the Best Practice Guide. Two main challenges are identified and the approaches taken to address them described: a) how to enable teachers to participate in the initial design stages, and b) ways of representing Learning Design to teachers. The role of design primitives, patterns, taxonomies, and templates is outlined, and interface issues for tool design are explored. A short description is provided of some key projects in the area, including ACETS, DialogPlus, 8LEM, MOT+ and LAMS