Fosamprenavir treatment in a highly active antiretroviral therapy schedule induces a HCV-RNA decrease and a Th1 network boost in HIV/HCV-coinfected patients

AbstractHIV/HCV co-infected naïve patients (four females and six males) were evaluated for their response to the following treatment schedule: [(AZT 300 mg + 3TC 300 mg twice daily) + (fosamprenavir 700 mg twice daily) + (RTV 100 mg)]. CD3+/CD4+ T cells, interferon-γ (INF-γ) and interleukin-4 (IL-4) HCV-specific response, viral loads and transaminase levels were evaluated at time 0, and after 1, 3 and 6 months of therapy (T0, T1, T3, and T6 respectively). HIV-RNA, HCV-RNA and transaminases decreased at T1 and T3 compared with T0 (Mann–Whitney p <0.001, p <0.01 and p <0.01, respectively). At all time points, CD4+ and HCV-specific INF-γ responses were higher (p <0.001; p <0.001), and IL-4 lower (p <0.01) after treatment. At T6, HCV-RNA was only negative in four out of ten patients whereas all had normal transaminase levels. These findings indicate that HAART treatment including fosamprenavir is able to activate a Th1 network in HIV/HCV co-infected patients. Moreover, these results, to be confirmed by larger cohort follow-up studies, suggest that this protease inhibitor could have potential implications for the treatment of chronic hepatitis C in HIV–positive patients

Tunneling spectroscopy studies of aluminum oxide tunnel barrier layers

We report scanning tunneling microscopy and ballistic electron emission microscopy studies of the electronic states of the uncovered and chemisorbed-oxygen covered surface of AlOx tunnel barrier layers. These states change when chemisorbed oxygen ions are moved into the oxide by either flood gun electron bombardment or by thermal annealing. The former, if sufficiently energetic, results in locally well defined conduction band onsets at ~1 V, while the latter results in a progressively higher local conduction band onset, exceeding 2.3 V for 500 and 600 C thermal anneals

Phase-sensitive imaging of cold atoms at the shot-noise limit

Extent: 5p.We demonstrate simultaneous phase and amplitude imaging of cold atoms using an intrinsically stable interferometer based on polarization beam-displacers. This method allows for the straight-forward retrieval of absorption and phase-shift experienced by an optical probe transmitted through an atomic sample. Furthermore, we show that our technique has a signal-to-noise ratio limited only by photon shot-noise. © 2013 AIP Publishing LLC.P. S. Light, C. Perrella, and A. N. Luite

Morphological, Gene, and Hormonal Changes in Gonads and In-Creased Micrococcal Nuclease Accessibility of Sperm Chromatin Induced by Mercury

Mercury is one of the most dangerous environmental pollutants. In this work, we analysed the effects of exposure of Mytilus galloprovincialis to 1, 10 and 100 pM HgCl2 for 24 h on the gonadal morphology and on the expression level of three stress genes: mt10, hsp70 and πgst. In this tissue we also evaluated the level of steroidogenic enzymes 3β-HSD and 17β-HSD and the expression of PL protein genes. Finally, we determined difference in sperm chromatin accessibility to micrococcal nuclease. We found alterations in gonadal morphology especially after exposure to 10 and 100 pM HgCl2 and hypo-expression of the three stress genes, particularly for hsp70. Furthermore, decreased labelling with both 3β-HSD and 17β-HSD antibodies was observed following exposure to 1 and 10 pM HgCl2 and complete absence at 100 pM HgCl2 exposure. Gonads of mussels exposed to all HgCl2 doses showed decreased expression of PL protein genes especially for PLIII. Finally, micrococcal nuclease digestions showed that all doses of HgCl2 exposure resulted in increased sperm chromatin accessibility to this enzyme, indicative of improper sperm chromatin structure. All of these changes provide preliminary data of the potential toxicity of mercury on the reproductive health of this mussel

High-efficiency cross-phase modulation in a gas-filled waveguide

Strong cross-Kerr nonlinearities have been long sought after for quantum information applications. Recent work has shown that they are intrinsically unreliable in traveling-wave configurations: cavity configurations avoid this, but require knowledge of both the nonlinearity and the loss. Here we present a detailed systematic study of cross-phase modulation and absorption in an Rb vapor confined within a hollow-core photonic crystal fiber. Using a two-photon transition, we observe phase modulations of up to pi rad with a signal power of 25 mu W, corresponding to a nonlinear Kerr coefficient, n(2), of 0.8 x 10(-6) cm(2)/W, or 1.3 x 10(-6) rad per photon

Objective Knowledge Mediates the Relationship between the Use of Social Media and COVID-19-Related False Memories

The exposure to relevant social and/or historical events can increase the generation of false memories (FMs). The Coronavirus Disease 2019 (COVID-19) pandemic is a calamity challenging health, political, and journalistic bodies, with media generating confusion that has facilitated the spread of fake news. In this respect, our study aims at investigating the relationships between memories (true memories, TMs vs. FMs) for COVID-19-related news and different individual variables (i.e., use of traditional and social media, COVID-19 perceived and objective knowledge, fear of the disease, depression and anxiety symptoms, reasoning skills, and coping mechanisms). One hundred and seventy-one university students (131 females) were surveyed. Overall, our results suggested that depression and anxiety symptoms, reasoning skills, and coping mechanisms did not affect the formation of FMs. Conversely, the fear of loved ones contracting the infection was found to be negatively associated with FMs. This finding might be due to an empathy/prosociality-based positive bias boosting memory abilities, also explained by the young age of participants. Furthermore, objective knowledge (i) predicted an increase in TMs and decrease in FMs and (ii) significantly mediated the relationships between the use of social media and development of both TMs and FMs. In particular, higher levels of objective knowledge strengthened the formation of TMs and decreased the development of FMs following use of social media. These results may lead to reconsidering the idea of social media as the main source of fake news. This claim is further supported by either the lack of substantial differences between the use of traditional and social media among participants reporting FMs or the positive association between use of social media and levels of objective knowledge. The knowledge about the topic rather than the type of source would make a difference in the process of memory formation

High-efficiency cold-atom transport into a waveguide trap

We develop and characterize an atom-guiding technique that loads 3×10⁶ cold rubidium atoms into a hollow-core optical fiber, an order-of-magnitude greater than previously reported results. This result is possible because it is guided by a physically realistic simulation that can provide the specifications for a loading efficiency of 3.0% and a peak optical depth of 600. The simulation further shows that the loading efficiency is limited solely by the geometric overlap of the atom cloud and the optical guide beam, and is thus open to further improvement with experimental modification. The experimental arrangement allows observation of the real-time effects of light-assisted cold-atom collisions and background-gas collisions by tracking the dynamics of the cold-atom cloud as it falls into the fiber. The combination of these observations, and physical understanding from the simulation, allows estimation of the limits to loading cold atoms into hollow-core fibers.A.P. Hilton, C. Perrella, F. Benabid, B.M. Sparkes, A.N. Luiten and P.S. Ligh

Engineering photon-photon interactions within rubidium-filled waveguides

Strong photon-photon interactions are a required ingredient for deterministic two-photon optical quantum logic gates. Multiphoton transitions in dense atomic vapors have been shown to be a promising avenue for producing such interactions. The strength of a multiphoton interaction can be enhanced by conducting the interaction in highly confined geometries such as small-cross-section optical waveguides. We demonstrate, both experimentally and theoretically, that the strength of such interactions scale only with the optical mode diameter, d, not d² as might be initially expected. This weakening of the interaction arises from atomic motion inside the waveguides. We create an interaction between two optical signals, at 780 and 776 nm, using the 5S₁⁄₂ → 5D₅⁄₂ two-photon transition in rubidium vapor within a range of hollow-core fibers with different core sizes. The interaction strength is characterized by observing the absorption and phase shift induced on the 780-nm beam, which is in close agreement with theoretical modeling that accounts for the atomic motion inside the fibers. These observations demonstrate that transit-time effects upon multiphoton transitions are of key importance when engineering photon-photon interactions within small-cross-section waveguides that might otherwise be thought to lead to enhanced optical nonlinearity through increased intensities.C. Perrella, P.S. Light, S. Afshar Vahid, F. Benabid, and A.N. Luite