5,923 research outputs found

    The envirome and the connectome: exploring the structural noise in the human brain associated with socioeconomic deprivation

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    Complex cognitive functions are widely recognized to be the result of a number of brain regions working together as large-scale networks. Recently, complex network analysis has been used to characterize various structural properties of the large scale network organization of the brain. For example, the human brain has been found to have a modular architecture i.e. regions within the network form communities (modules) with more connections between regions within the community compared to regions outside it. The aim of this study was to examine the modular and overlapping modular architecture of the brain networks using complex network analysis. We also examined the association between neighborhood level deprivation and brain network structure – modularity and grey nodes. We compared network structure derived from anatomical MRI scans of 42 middle-aged neurologically healthy men from the least (LD) and the most deprived (MD) neighborhoods of Glasgow with their corresponding random networks. Cortical morphological covariance networks were constructed from the cortical thickness derived from the MRI scans of the brain. For a given modularity threshold, networks derived from the MD group showed similar number of modules compared to their corresponding random networks, while networks derived from the LD group had more modules compared to their corresponding random networks. The MD group also had fewer grey nodes – a measure of overlapping modular structure. These results suggest that apparent structural difference in brain networks may be driven by differences in cortical thicknesses between groups. This demonstrates a structural organization that is consistent with a system that is less robust and less efficient in information processing. These findings provide some evidence of the relationship between socioeconomic deprivation and brain network topology

    High Altitude Rangelands and Pastoralism in Bhutan: Using Sustainable Development Goals to Address Land Degradation and Poverty

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    Semi-nomadic pastoralists in Bhutan live in high altitude rangelands where they seasonally migrate with yak and cattle herds from 3,000m to 5,000m. Population increase, overgrazing and climate change in eastern Bhutan have led to severe land degradation, winter fodder shortage and reduced milk production per head for herding families. This paper describes how Sustainable Development Goals (SDGs) were used to design a rangeland rehabilitation and livelihoods improvement program with herders in Merak district from 2016 to 2019. The aim was to restore degraded rangelands, improve pastures, develop savings schemes, resolve conflicts and increase conservation knowledge. The approach involved gender sensitive capacity building, on-ground works, action research and social learning. Six SDGs were addressed over three years, SDG 1. No Poverty; SDG 4 Quality Education; SDG 5 Gender Equality; SDG 8 Decent work and economic growth; and SDG 15 Life on the Land. Poverty in Merak district is higher than the rest of Bhutan due to remoteness and lack of livelihood alternatives. Two women’s savings groups were formed in 2017 with 148 members, each investing 100-150 Ngultrum per month (US23).Intwoyears,thegroupssaved(US2-3). In two years, the groups saved (US3,700) with (US$2,363) borrowed by 10 households for enterprises such as cheese making, wooden bowls, small shops, carpentry, homestays and livestock. The community were trained in organisational and financial management which increased their confidence and skills in working together and resolving conflicts. Eroded rangeland areas were fenced, reforested and checkdams installed. Pasture was sown over 80 hectares at 3,000m and silage produced for winter feed. Collaborative learning between the forest and livestock agencies, environmental NGOs and the community led to declaration of special protection zones, a red panda conservation action plan, junior ranger clubs and a wool processing centre. Challenges included communal areas where families could not agree on whether to improve pasture which required fencing investment. The SDGs provided a useful framework for achieving and monitoring outcomes of integrated rangeland management and livelihood development

    Low loss Ge-on-Si waveguides operating in the 8–14 µm atmospheric transmission window

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    Germanium-on-silicon waveguides were modeled, fabricated and characterized at wavelengths ranging from 7.5 to 11 µm. Measured waveguide losses are below 5 dB/cm for both TE and TM polarization and reach values of ∼ 1 dB/cm for ≥ 10 µm wavelengths for the TE polarization. This work demonstrates experimentally for the first time that Ge-on-Si is a viable waveguide platform for sensing in the molecular fingerprint spectral region. Detailed modeling and analysis is presented to identify the various loss contributions, showing that with practical techniques losses below 1 dB/cm could be achieved across the full measurement range

    Light and circadian regulation of clock components aids flexible responses to environmental signals

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    The circadian clock measures time across a 24h period, increasing fitness by phasing biological processes to the most appropriate time of day. The interlocking feedback loop mechanism of the clock is conserved across species; however, the number of loops varies. Mathematical and computational analyses have suggested that loop complexity affects the overall flexibility of the oscillator, including its responses to entrainment signals. We used a discriminating experimental assay, at the transition between different photoperiods, in order to test this proposal in a minimal circadian network (in Ostreococcus tauri) and a more complex network (in Arabidopsis thaliana). Transcriptional and translational reporters in O.tauri primarily tracked dawn or dusk, whereas in A.thaliana, a wider range of responses were observed, consistent with its more flexible clock. Model analysis supported the requirement for this diversity of responses among the components of the more complex network. However, these and earlier data showed that the O.tauri network retains surprising flexibility, despite its simple circuit. We found that models constructed from experimental data can show flexibility either from multiple loops and/or from multiple light inputs. Our results suggest that O.tauri has adopted the latter strategy, possibly as a consequence of genomic reduction

    Mid-infrared intersubband absorption from p-Ge quantum wells grown on Si substrates

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    Mid-infrared intersubband absorption from p-Ge quantum wells with Si0.5Ge0.5 barriers grown on a Si substrate is demonstrated from 6 to 9 μm wavelength at room temperature and can be tuned by adjusting the quantum well thickness. Fourier transform infra-red transmission and photoluminescence measurements demonstrate clear absorption peaks corresponding to intersubband transitions among confined hole states. The work indicates an approach that will allow quantum well intersubband photodetectors to be realized on Si substrates in the important atmospheric transmission window of 8–13 μm

    Mid-Infrared Intersubband Absorption from P-Ge Quantum Wells on Si

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    Mid-infrared intersubband absorption from p-Ge quantum wells with Si0.5Ge0.5 barriers grown on a Si substrate is demonstrated from 6 to 9 μm wavelength at room temperature and can be tuned by adjusting the quantum well thickness. Fourier transform infra-red spectroscopy measurements demonstrate clear absorption peaks corresponding to intersubband transitions among confined hole states. The work indicates an approach that will allow quantum well intersubband photodetectors to be realized on Si substrates in the important atmospheric transmission window of 8–13 μm

    AI as a legal person

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    Abstract: The idea of the legal personhood of artificial intelligence (AI) — the idea that intelligent agents can have rights and incur obligations under the law— is controversial, and in fact is often dismissed out of hand: in this paper I will argue that, on the contrary, such legal personhood may be the next big challenge for our legal systems, and we need it to deal with the new kinds ofcomplexity introduced by AI. Furthermore, I argue that we already have experiences we can look: to this end we can draw on the reasoning applied to the legal personhood recognized for corporations and other nonhuman entities. In order to do this, I address some of the criticisms against ascribing legal personhood to AI. I also look at the Canadian and EU ethical guidelines so as to keep the development of AI within the framework of human values, and I show that an ascription of legal personhood to AI is consistent with them. I also address a few of the big issues involved in making the legal personhood of AI a reality.This paper is part of the project supported by the CONEX programme and has received funding from the Universidad Carlos III de Madrid, the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement N. 600371, el Ministerio de Economia, Industria y Competitividad (COFUND2014-51509), el Ministerio de Educacion, Cultura y Deporte (CEI-15-17) and Banco SantanderUniversidad Carlos III de Madrid (APC. Read & Publish Agreement CRUE-CSIC 2023

    The effect of transmucosal 0.2mg/kg Midazolam premedication on dental anxiety, anaesthetic induction and psychological morbidity in children undergoing general anaesthesia for tooth extraction

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    <b>Background:</b> The project aims were to evaluate the benefit of transmucosal Midazolam 0.2mg/kg pre-medication on anxiety, induction behaviour and psychological morbidity in children undergoing general anaesthesia (GA) extractions. <b>Method:</b> 179 children aged 5-10 years (mean 6.53 years) participated in this randomised, double blind, placebo controlled trial. Ninety children had Midazolam placed in the buccal pouch. Dental anxiety was recorded pre operatively and 48 hours later using a child reported MCDAS-FIS scale. Behaviour at anaesthetic induction was recorded and psychological morbidity was scored by the parent using the Rutter Scale pre-operatively and again one-week later. Subsequent dental attendance was recorded at one, three and six months after GA. <b>Results:</b> Whilst levels of mental anxiety did not reduce overall, the most anxious patients demonstrated a reduction in anxiety after receiving midazolam premedicationmay (p=0.01). Neither induction behaviour nor psychological morbidity improved. Irrespective of group, parents reported less hyperactive (p= 0.002) and more prosocial behaviour (p=0.002) after the procedure:;, older children improved most (p=0.048), Post GA Dental attendance was poor and unrelated to after the procedure and unaffected by premedication. <b>Conclusion:</b> 0.2mg/kg buccal Midazolam provided some evidence for reducing anxiety in the most dentally anxious patients. However, induction behaviour, psychological morbidity and subsequent dental attendance were not found to alter between the premedication groups

    Slow-light optical bullets in arrays of nonlinear Bragg-grating waveguides

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    We demonstrate how to control independently both spatial and temporal dynamics of slow light. We reveal that specially designed nonlinear waveguide arrays with phase-shifted Bragg gratings demonstrate the frequency-independent spatial diffraction near the edge of the photonic bandgap, where the group velocity of light can be strongly reduced. We show in numerical simulations that such structures allow a great flexibility in designing and controlling dispersion characteristics, and open a way for efficient spatiotemporal self-trapping and the formation of slow-light optical bullets.Comment: 4 pages, 4 figures; available from http://link.aps.org/abstract/PRL/v97/e23390
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