Electronic and magnetic structure of epitaxial NiO/Fe3_3O4_4(001) heterostructures grown on MgO(001) and Nb-doped SrTiO3_3(001)

We study the underlying chemical, electronic and magnetic properties of a number of magnetite based thin films. The main focus is placed onto NiO/Fe$_3$O$_4$(001) bilayers grown on MgO(001) and Nb-SrTiO$_3$(001) substrates. We compare the results with those obtained on pure Fe$_3$O$_4$(001) thin films. It is found that the magnetite layers are oxidized and Fe$^{3+}$ dominates at the surfaces due to maghemite ($\gamma$-Fe$_2$O$_3$) formation, which decreases with increasing magnetite layer thickness. From a layer thickness of around 20 nm on the cationic distribution is close to that of stoichiometric Fe$_3$O$_4$. At the interface between NiO and Fe$_3$O$_4$ we find the Ni to be in a divalent valence state, with unambiguous spectral features in the Ni 2p core level x-ray photoelectron spectra typical for NiO. The formation of a significant NiFe$_2$O$_4$ interlayer can be excluded by means of XMCD. Magneto optical Kerr effect measurements reveal significant higher coercive fields compared to magnetite thin films grown on MgO(001), and a 45$^{\circ}$ rotated magnetic easy axis. We discuss the spin magnetic moments of the magnetite layers and find that the moment increases with increasing thin film thickness. At low thickness the NiO/Fe$_3$O$_4$ films grown on Nb-SrTiO$_3$ exhibits a significantly decreased spin magnetic moments. A thickness of 20 nm or above leads to spin magnetic moments close to that of bulk magnetite

Utilisation du Raltegravir chez des patients infectés par HIV-1 group O

International audienc

Candidate chemoreceptor subfamilies differentially expressed in the chemosensory organs of the mollusc Aplysia

<p>Abstract</p> <p>Background</p> <p>Marine molluscs, as is the case with most aquatic animals, rely heavily on olfactory cues for survival. In the mollusc <it>Aplysia californica</it>, mate-attraction is mediated by a blend of water-borne protein pheromones that are detected by sensory structures called rhinophores. The expression of G protein and phospholipase C signaling molecules in this organ is consistent with chemosensory detection being via a G-protein-coupled signaling mechanism.</p> <p>Results</p> <p>Here we show that novel multi-transmembrane proteins with similarity to rhodopsin G-protein coupled receptors are expressed in sensory epithelia microdissected from the <it>Aplysia </it>rhinophore. Analysis of the <it>A. californica </it>genome reveals that these are part of larger multigene families that possess features found in metazoan chemosensory receptor families (that is, these families chiefly consist of single exon genes that are clustered in the genome). Phylogenetic analyses show that the novel <it>Aplysia </it>G-protein coupled receptor-like proteins represent three distinct monophyletic subfamilies. Representatives of each subfamily are restricted to or differentially expressed in the rhinophore and oral tentacles, suggesting that they encode functional chemoreceptors and that these olfactory organs sense different chemicals. Those expressed in rhinophores may sense water-borne pheromones. Secondary signaling component proteins Gα_q, Gα_i, and Gα_oare also expressed in the rhinophore sensory epithelium.</p> <p>Conclusion</p> <p>The novel rhodopsin G-protein coupled receptor-like gene subfamilies identified here do not have closely related identifiable orthologs in other metazoans, suggesting that they arose by a lineage-specific expansion as has been observed in chemosensory receptor families in other bilaterians. These candidate chemosensory receptors are expressed and often restricted to rhinophores and oral tentacles, lending support to the notion that water-borne chemical detection in <it>Aplysia </it>involves species- or lineage-specific families of chemosensory receptors.</p

Forest biomass retrieval approaches from earth observation in different biomes

The amount and spatial distribution of forest aboveground biomass (AGB) were estimated using a range of regionally developed methods using Earth Observation data for Poland, Sweden and regions in Indonesia (Kalimantan), Mexico (Central Mexico and Yucatan peninsula), and South Africa (Eastern provinces) for the year 2010. These regions are representative of numerous forest biomes and biomass levels globally, from South African woodlands and savannas to the humid tropical forest of Kalimantan. AGB retrieval in each region relied on different sources of reference data, including forest inventory plot data and airborne LiDAR observations, and used a range of retrieval algorithms. This is the widest inter-comparison of regional-to-national AGB maps to date in terms of area, forest types, input datasets, and retrieval methods. The accuracy assessment of all regional maps using independent field data or LiDAR AGB maps resulted in an overall root mean square error (RMSE) ranging from 10 t ha−1 to 55 t ha−1 (37% to 67% relative RMSE), and an overall bias ranging from −1 t ha−1 to +5 t ha−1 at pixel level. The regional maps showed better agreement with field data than previously developed and widely used pan-tropical or northern hemisphere datasets. The comparison of accuracy assessments showed commonalities in error structures despite the variety of methods, input data, and forest biomes. All regional retrievals resulted in overestimation (up to 63 t ha−1) in the lower AGB classes, and underestimation (up to 85 t ha−1) in the higher AGB classes. Parametric model-based algorithms present advantages due to their low demand on in situ data compared to non-parametric algorithms, but there is a need for datasets and retrieval methods that can overcome the biases at both ends of the AGB range. The outcomes of this study should be considered when developing algorithms to estimate forest biomass at continental to global scale level

Citizen science’s transformative impact on science, citizen empowerment and socio-political processes

Citizen science (CS) can foster transformative impact for science, citizen empowerment and socio-political processes. To unleash this impact, a clearer understanding of its current status and challenges for its development is needed. Using quantitative indicators developed in a collaborative stakeholder process, our study provides a comprehensive overview of the current status of CS in Germany, Austria and Switzerland. Our online survey with 340 responses focused on CS impact through (1) scientific practices, (2) participant learning and empowerment, and (3) socio-political processes. With regard to scientific impact, we found that data quality control is an established component of CS practice, while publication of CS data and results has not yet been achieved by all project coordinators (55%). Key benefits for citizen scientists were the experience of collective impact (“making a difference together with others”) as well as gaining new knowledge. For the citizen scientists’ learning outcomes, different forms of social learning, such as systematic feedback or personal mentoring, were essential. While the majority of respondents attributed an important value to CS for decision-making, only few were confident that CS data were indeed utilized as evidence by decision-makers. Based on these results, we recommend (1) that project coordinators and researchers strengthen scientific impact by fostering data management and publications, (2) that project coordinators and citizen scientists enhance participant impact by promoting social learning opportunities and (3) that project initiators and CS networks foster socio-political impact through early engagement with decision-makers and alignment with ongoing policy processes. In this way, CS can evolve its transformative impact

Mitigating the risk posed by fixated persons at major events: a joint police-mental health intelligence approach

The Queensland Fixated Threat Assessment Centre (QFTAC) is an integrated police-mental health agency established in Queensland, Australia, in 2013 to deal specifically with lone, fixated persons. Many of these individuals are mentally ill, but are unknown to psychiatric services or have disengaged from care. QFTAC identifies fixated persons through their ominous contacts with public office holders and intervenes, often by facilitating mental health care, to prevent progression to harmful outcomes. Prior to the G20 Meetings convened in Queensland in 2014 there was no empirically based procedural framework for managing fixated persons at major public figure gatherings. This paper describes the development of a diversionary model for assessing and managing fixated persons during major events, which combined the resources and expertise of police intelligence officers and forensic mental health practitioners. This approach effectively mitigated the risk posed by fixated individuals to delegates, staff and mentally ill intruders in the secure, armed environment of these events. The model highlights the importance for police, security and mental health services of considering fixated loners in major event planning, for the safety of the event, the public and vulnerable, mentally ill, fixated persons

Utilisation du Raltegravir chez des patients infectés par HIV-1 group O

International audienc

A model for managing the mentally ill fixated person at major events

Objective: The main risk of serious harm at major public figure gatherings comes not from terrorists or criminal activity but from fixated persons, many of whom have a serious mental illness. This paper reviews a collaborative mental healthpolice diversionary model for assessing and managing mentally ill individuals who attend major events because of their fixation on a dignitary or some idiosyncratic cause. Method: We examine the role of a multidisciplinary fixated threat assessment service during the pre-operational, operational and post-operational phases of major events in Queensland in 2014, including the G20 World Leaders? Summit. The benefits and challenges of this unique approach are reviewed. Results: The royal visit and G20 Finance Ministers? Meeting presented opportunities for the Queensland Fixated Threat Assessment Centre to develop and refine its approach to assessing and managing the threat posed by fixated persons at such events. Based on this experience, we also developed a typology to assist in the assessment of mentally ill people who present at public figure gatherings. In the week prior to the G20 Summit, six fixated people required hospitalisation for acute psychosis. A further 18 cases were identified during the event, one of whom was an involuntary patient whose leave from hospital was revoked as a consequence of his concerning behaviour at one of the G20 venues. There were no other admissions to hospital during the event, but in the remaining cases, where indicated, follow-up was arranged through the treating mental health service or general practitioner. There were no disruptive incidents involving fixated individuals during the G20. Conclusion: This novel diversionary model for assessing and intervening with concerning, fixated persons at major events proved effective in mitigating the risk posed by these individuals. It also highlighted the need for police, security and mental health services to consider the fixated in major event planning, for the safety of the event, the public and vulnerable mentally ill, fixated persons

Abnormal attentions toward the British royal family: Factors associated with approach and escalation

Abnormal approach and escalation from communication to physical intrusion are central concerns in managing risk to prominent people. This study was a retrospective analysis of police files of those who have shown abnormal attentions toward the British Royal Family. Approach (n = 222), compared with communication only (n = 53), was significantly associated with specific factors, most notably serious mental illness and grandiosity. In a sample of those who engaged in abnormal communication (n = 132), those who approached (n = 79) were significantly more likely to evidence mental illness and grandiosity, to use multiple communications, to employ multiple means of communication, and to be driven by motivations that concerned a personal entitlement to the prominent individual. Logistic regression produced a model comprising grandiosity, multiple communications, and multiple means of communication, for which receiver operating characteristic (ROC) analysis gave an area under the curve (AUC) of 0.82. The implications of these findings are discussed in relation to those for other target groups. Copyright © 2010 by the American Academy of Psychiatry and the Law