36 research outputs found

    Phononic bath engineering of a superconducting qubit

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    Phonons, the ubiquitous quanta of vibrational energy, play a vital role in the performance of many quantum technologies. Coupling to well-defined phonon modes allows for highly-connected multi-qubit gates in ion trap architectures as well as the generation of entangled states in systems of superconducting qubits. Even when the phonons take the form of a large dissipative bath, an irreversible flow of heat allows for state initialization critical to the function of laser systems and the operation of optically active spin qubits. Conversely, unintended coupling to phonons has been shown to degrade qubit performance by generating decohering quasiparticles and leading to correlated errors in superconducting qubit systems. Regardless of whether a phononic bath plays an enabling or deleterious role, it is typically intrinsic to the system and does not admit specific control over its spectral properties, nor the possibility of engineering aspects of its dissipation to be used as a resource. Here we show that by precisely designing and controlling the coupling of a superconducting qubit to phononic degrees of freedom allows a new type of quantum control over superconducting circuits. By shaping the loss spectrum of the qubit via its coupling to a bath of lossy piezoelectric surface acoustic wave phonons, we are able to prepare and stabilize arbitrary qubit states. Additionally, we find that the presence of the energy-dependent loss imparted onto the qubit by the phonons is well-described by a master equation treatment of the composite system, with excellent agreement in both the qubit dynamics as well as its steady state. Our results demonstrate the ability of engineered phononic dissipation to achieve highly efficient qubit control.Comment: 18 pages, 5 figures, 1 table, main text and S

    Structure of the mirror nuclei 9^9Be and 9^9B in a microscopic cluster model

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    The structure of the mirror nuclei 9^9Be and 9^9B is studied in a microscopic α+α+n\alpha+ \alpha+ n and α+α+p\alpha+ \alpha+ p three-cluster model using a fully antisymmetrized 9-nucleon wave function. The two-nucleon interaction includes central and spin-orbit components and the Coulomb potential. The ground state of 9^9Be is obtained accurately with the stochastic variational method, while several particle-unbound states of both 9^9Be and 9^9B are investigated with the complex scaling method.The calculation for 9^9Be supports the recent identification for the existence of two broad states around 6.5 MeV, and predicts the 322\frac{3}{2}^{-}_2 and 522\frac{5}{2}^{-}_2 states at about 4.5 MeV and 8 MeV, respectively. The similarity of the calculated spectra of 9^9Be and 9^9B enables one to identify unknown spins and parities of the 9^9B states. Available data on electromagnetic moments and elastic electron scatterings are reproduced very well. The enhancement of the EE1 transition of the first excited state in 9^9Be is well accounted for. The calculated density of 9^9Be is found to reproduce the reaction cross section on a Carbon target. The analysis of the beta decay of 9^9Li to 9^9Be clearly shows that the wave function of 9^9Be must contain a small component that cannot be described by the simple α+α+n\alpha+ \alpha+ n model. This small component can be well accounted for by extending a configuration space to include the distortion of the α\alpha-particle to t+pt+p and h+nh+n partitions.Comment: 24 page

    Moving toward and through trauma: participant experiences of multi-modal motion-assisted memory desensitization and reconsolidation (3MDR)

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    Introduction: Military members and Veterans are at risk of developing combat-related, treatment-resistant posttraumatic stress disorder (TR-PTSD) and moral injury (MI). Conventional trauma-focused therapies (TFTs) have shown limited success. Novel interventions including Multi-modal Motion-assisted Memory Desensitization and Reconsolidation therapy (3MDR) may prove successful in treating TR-PTSD.Objective: To qualitatively study the experiences of Canadian military members and Veterans with TR-PTSD who received the 3MDR intervention.Methods: This study explored qualitative data from a larger mixed-method waitlist control trial testing the efficacy of 3MDR in military members and veterans. Qualitative data were recorded and collected from 3MDR sessions, session debriefings and follow-up interviews up to 6 months post-intervention; the data were then thematically analyzed.Results: Three themes emerged from the data: (1) the participants' experiences with 3MDR; (2) perceived outcomes of 3MDR; and (3) keys to successful 3MDR treatment. Participants expressed that 3MDR provided an immersive environment, active engagement and empowerment. The role of the therapist as a coach and "fireteam partner" supports the participants' control over their therapy. The multi-modal nature of 3MDR, combining treadmill-walking toward self-selected trauma imagery with components of multiple conventional TFTs, was key to helping participants engage with and attribute new meaning to the memory of the traumatic experience.Discussion: Preliminary thematic analysis of participant experiences of 3MDR indicate that 3MDR has potential as an effective intervention for combat-related TR-PTSD, with significant functional, well-being and relational improvements reported post-intervention.Conclusion: Military members and Veterans are at risk of developing TR-PTSD, with worse outcomes than in civilians. Further research is needed into 3MDR and its use with other trauma-affected populations.Stress-related psychiatric disorders across the life spa

    Natural disturbance impacts on trade-offs and co-benefits of forest biodiversity and carbon

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    With accelerating environmental change, understanding forest disturbance impacts on trade-offs between biodiversity and carbon dynamics is of high socio-economic importance. Most studies, however, have assessed immediate or short-term effects of disturbance, while long-term impacts remain poorly understood. Using a tree-ring-based approach, we analysed the effect of 250 years of disturbances on present-day biodiversity indicators and carbon dynamics in primary forests. Disturbance legacies spanning centuries shaped contemporary forest co-benefits and trade-offs, with contrasting, local-scale effects. Disturbances enhanced carbon sequestration, reaching maximum rates within a comparatively narrow post-disturbance window (up to 50 years). Concurrently, disturbance diminished aboveground carbon storage, which gradually returned to peak levels over centuries. Temporal patterns in biodiversity potential were bimodal; the first maximum coincided with the short-term post-disturbance carbon sequestration peak, and the second occurred during periods of maximum carbon storage in complex old-growth forest. Despite fluctuating local-scale trade-offs, forest biodiversity and carbon storage remained stable across the broader study region, and our data support a positive relationship between carbon stocks and biodiversity potential. These findings underscore the interdependencies of forest processes, and highlight the necessity of large-scale conservation programmes to effectively promote both biodiversity and long-term carbon storage, particularly given the accelerating global biodiversity and climate crises

    ANN multiscale model of anti-HIV Drugs activity vs AIDS prevalence in the US at county level based on information indices of molecular graphs and social networks

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    [Abstract] This work is aimed at describing the workflow for a methodology that combines chemoinformatics and pharmacoepidemiology methods and at reporting the first predictive model developed with this methodology. The new model is able to predict complex networks of AIDS prevalence in the US counties, taking into consideration the social determinants and activity/structure of anti-HIV drugs in preclinical assays. We trained different Artificial Neural Networks (ANNs) using as input information indices of social networks and molecular graphs. We used a Shannon information index based on the Gini coefficient to quantify the effect of income inequality in the social network. We obtained the data on AIDS prevalence and the Gini coefficient from the AIDSVu database of Emory University. We also used the Balaban information indices to quantify changes in the chemical structure of anti-HIV drugs. We obtained the data on anti-HIV drug activity and structure (SMILE codes) from the ChEMBL database. Last, we used Box-Jenkins moving average operators to quantify information about the deviations of drugs with respect to data subsets of reference (targets, organisms, experimental parameters, protocols). The best model found was a Linear Neural Network (LNN) with values of Accuracy, Specificity, and Sensitivity above 0.76 and AUROC > 0.80 in training and external validation series. This model generates a complex network of AIDS prevalence in the US at county level with respect to the preclinical activity of anti-HIV drugs in preclinical assays. To train/validate the model and predict the complex network we needed to analyze 43,249 data points including values of AIDS prevalence in 2,310 counties in the US vs ChEMBL results for 21,582 unique drugs, 9 viral or human protein targets, 4,856 protocols, and 10 possible experimental measures.Ministerio de Educación, Cultura y Deportes; AGL2011-30563-C03-0

    Where are we now with European forest multi-taxon biodiversity and where can we head to?

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    The European biodiversity and forest strategies rely on forest sustainable management (SFM) to conserve forest biodiversity. However, current sustainability assessments hardly account for direct biodiversity indicators. We focused on forest multi-taxon biodiversity to: i) gather and map the existing information; ii) identify knowledge and research gaps; iii) discuss its research potential. We established a research network to fit data on species, standing trees, lying deadwood and sampling unit description from 34 local datasets across 3591 sampling units. A total of 8724 species were represented, with the share of common and rare species varying across taxonomic classes: some included many species with several rare ones (e.g., Insecta); others (e.g., Bryopsida) were represented by few common species. Tree-related structural attributes were sampled in a subset of sampling units (2889; 2356; 2309 and 1388 respectively for diameter, height, deadwood and microhabitats). Overall, multi-taxon studies are biased towards mature forests and may underrepresent the species related to other developmental phases. European forest compositional categories were all represented, but beech forests were over-represented as compared to thermophilous and boreal forests. Most sampling units (94%) were referred to a habitat type of conservation concern. Existing information may support European conservation and SFM strategies in: (i) methodological harmonization and coordinated monitoring; (ii) definition and testing of SFM indicators and thresholds; (iii) data-driven assessment of the effects of environmental and management drivers on multi-taxon forest biological and functional diversity, (iv) multi-scale forest monitoring integrating in-situ and remotely sensed information

    Exploratory study of ultraviolet B (UVB) radiation and age of onset of bipolar disorder

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    Background: Sunlight contains ultraviolet B (UVB) radiation that triggers the production of vitamin D by skin. Vitamin D has widespread effects on brain function in both developing and adult brains. However, many people live at latitudes (about > 40 N or S) that do not receive enough UVB in winter to produce vitamin D. This exploratory study investigated the association between the age of onset of bipolar I disorder and the threshold for UVB sufficient for vitamin D production in a large global sample. Methods: Data for 6972 patients with bipolar I disorder were obtained at 75 collection sites in 41 countries in both hemispheres. The best model to assess the relation between the threshold for UVB sufficient for vitamin D production and age of onset included 1 or more months below the threshold, family history of mood disorders, and birth cohort. All coefficients estimated at P ≤ 0.001. Results: The 6972 patients had an onset in 582 locations in 70 countries, with a mean age of onset of 25.6 years. Of the onset locations, 34.0% had at least 1 month below the threshold for UVB sufficient for vitamin D production. The age of onset at locations with 1 or more months of less than or equal to the threshold for UVB was 1.66 years younger. Conclusion: UVB and vitamin D may have an important influence on the development of bipolar disorder. Study limitations included a lack of data on patient vitamin D levels, lifestyles, or supplement use. More study of the impacts of UVB and vitamin D in bipolar disorder is needed to evaluate this supposition

    Mining subsidence monitoring of highway between Ostrava and Frydek-Místek,CZE

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    Artykuł został poświęcony ocenie wpływu ruchu nadkładu wydobytych złóż minerałów użytkowych na obiekty budowlane znajdujące się na powierzchni ziemi, konkretnie wpływ wydobycia przodku wybierkowego Nr. 063 541 w obszarze górniczym "Staríc" na czteropasmową autostradę R 56 z Ostrawy do Frýdku-Místku. W celu monitorowania tych efektów została wybudowana stacja obserwacyjna, przy pomocy której wykonywano pomiary. Do stworzenia takiej stacji oraz do oceny uzyskanych pomiarów został zastosowany program SUBSCH, który pozwala na obliczenie osiadań (pionowego i poziomego), upadu, promienia krzywizny i poziomych przekształceń, w określonych przedziałach czasowych.The paper deals with effect of hanging wall movement of over mined deposits of economic minerals upon the Earth surface objects, specially the mining effect of the face 063 541 in mining area "Staríc" upon R 56 fourlane highway between Ostrava and Frýdek-Místek,CZE. The observation station has been established and measurement for monitoring the effect upon it was done. SUBSCH software was used to establish the observation station and to evaluate resultes. Subsidence, horizontal movement, denivelation, curvature radius and horizontal deformation for given instant time can be calculated in this software
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