1,680 research outputs found

    Medicinal plants from the Himalayan region as potential novel antimicrobial and anti-inflammatory skin treatments

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    Background and Objectives: Adequate treatment of wounds remains one of the major medical needs globally, most notably in the regions with poor or limited access to health care. In many local and traditional systems of medicine, plants are often widely used for treating infected wounds. / Aim and objectives: The overarching aim of this project was selection of potential species for use in a future treatment by combining with plant resources with aspects of antimicrobial photodynamic therapy (aPDT). Specifically, we focussed on species used locally in the Himalayan region for the treatment of skin disorders and then assessed the existing pharmacological evidence for key species based on the published evidence available. / Methods: Database searches were performed to identify relevant publications describing local and traditional uses of plants in the Himalayan region of Bhutan, PR China, India, Nepal and Pakistan. Using the Global Biodiversity Information Facility (GBIF), species were researched in terms of their distribution including in different climatic regions, focussing on species mostly found in higher climatic zones (based on the Köppen–Geiger climate classification). For species used in three or more countries and restricted to the higher altitudes, data on safety, pharmacology, as it relates to dermatological conditions, and phytochemistry were retrieved. / Key findings: The study identified a total of 606 species that are used in the treatment of various skin conditions often associated with infections reported in 84 articles. Common weeds like Ageratum conyzoides and Bidens pilosa, widely used and cultivated species like Centealla asiatiaca and Prunus armenica were excluded. This ultimately led to the identification of a core group of five widely used species restricted to the Himalayan region (Cedrus deodara, Nardostachys jatamansi, Pinus wallichiana, Pinus roxburghii and Valeriana jatamansi). / Conclusions: Here we apply a novel approach comprising an assessment of the published information on the use of medicinal plants (i.e. local and traditional knowledge) in the context of their potential to be used in a biomedical form of clinical treatment – aPDT. Then, once sustainable sourcing based on access and benefit-sharing arrangements is in place, these species are investigated for their potential in wound treatment. Ultimately, the goal is to develop a new baseline for primary health care in some of the regions of the world with poor or limited access to health care

    Thomas-Fermi approach to resonant tunneling in delta-doped diodes

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    We study resonant tunneling in B-ÎŽ\delta-doped diodes grown by Si-molecular beam epitaxy. A Thomas-Fermi approach is used to obtain the conduction-band modulation. Using a scalar Hamiltonian within the effective-mass approximation we demonstrate that the occurrence of negative differential resistance (NDR) only involves conduction-band states, whereas interband tunneling effects seem to be negligible. Our theoretical results are in very good agreement with recent experimental observations of NDR in this type of diodes.Comment: 6 pages, REVTeX 3.0, 5 figures available from [email protected]

    Convection in colloidal suspensions with particle-concentration-dependent viscosity

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    The onset of thermal convection in a horizontal layer of a colloidal suspension is investigated in terms of a continuum model for binary-fluid mixtures where the viscosity depends on the local concentration of colloidal particles. With an increasing difference between the viscosity at the warmer and the colder boundary the threshold of convection is reduced in the range of positive values of the separation ratio psi with the onset of stationary convection as well as in the range of negative values of psi with an oscillatory Hopf bifurcation. Additionally the convection rolls are shifted downwards with respect to the center of the horizontal layer for stationary convection (psi>0) and upwards for the Hopf bifurcation (psi<0).Comment: 8 pages, 6 figures, submitted to European Physical Journal

    "From ‘What the hell is going on?’ to the ‘Mushy middle ground’ to ‘getting used to a new normal’: Young people’s biographical narratives around navigating parental dementia"

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    The number of young people who have a parent with dementia is rising as a result of improvements in diagnosis of young onset variants and demographic shifts. There has, however, been very little research focusing on this group. Accounts elicited as part of the Perceptions and Experiences of Young People With a Parent With Dementia described the period, usually some years, leading up to a diagnosis of a dementia and then the progress of the condition post diagnosis. These narratives were characterised by confusion, uncertainty, trauma and distress as the young people struggled to make sense of the significant and often extreme, behavioural and attitudinal changes that were symptoms of the illness. This paper describes and discusses how the young people experienced and navigated the temporal messiness and consequent biographical disruption arising from parental dementia

    Lubricated revolute joints in rigid multibody systems

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    The main purpose of this work is to present a general methodology for modeling lubricated revolute joints in constrained rigid multibody systems. In the dynamic analysis of journal-bearings, the hydrodynamic forces, which include both squeeze and wedge effects, generated by the lubricant fluid, oppose the journal motion. The hydrodynamic forces are obtained by integrating the pressure distribution evaluated with the aid of Reynolds’ equation, written for the dynamic regime. The hydrodynamic forces built up by the lubricant fluid are evaluated from the system state variables and included into the equations of motion of the multibody system. Numerical examples are presented in order to demonstrate the use of the methodologies and procedures described in this work.Fundação para a CiĂȘncia e a Tecnologia (FCT

    Design, Participation, and Social Change: What Design in Grassroots Spaces Can Teach Learning Scientists

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    hile a science of design (and theory of learning) is certainly useful in design-based research, a participatory design research framework presents an opening for learning scientists to rethink design and learning as processes. Grounded in the autoethnographic investigation of a grassroots organization\u27s design of a local campaign, the author traces the successive transformations of design artifacts, delineating a narrative character to design within grassroots spaces. One major lesson is that centering the question of participation is not just about including historically marginalized peoples at the core of design; it has the potential to “desettle” projects at a fundamental level, challenging dominant epistemologies that inform the practices of learning scientists, and thus transforming the field in ways that have yet to be systematically explored. More broadly, this study highlights the need for future research on design practices as they take form within understudied spaces, such as grassroots organizations

    A double-sided, shield-less stave prototype for the ATLAS upgrade strip tracker for the high luminosity LHC

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    A detailed description of the integration structures for the barrel region of the silicon strips tracker of the ATLAS Phase-II upgrade for the upgrade of the Large Hadron Collider, the so-called High Luminosity LHC (HL-LHC), is presented. This paper focuses on one of the latest demonstrator prototypes recently assembled, with numerous unique features. It consists of a shortened, shield-less, and double sided stave, with two candidate power distributions implemented. Thermal and electrical performances of the prototype are presented, as well as a description of the assembly procedures and tools

    Quantum-Enhanced Advanced LIGO Detectors in the Era of Gravitational-Wave Astronomy

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    The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in the direct measurement of gravitational waves with the Advanced LIGO H1 and L1 detectors. This achievement is the culmination of decades of research to implement squeezed states in gravitational-wave detectors. During the ongoing O3 observation run, squeezed states are improving the sensitivity of the LIGO interferometers to signals above 50 Hz by up to 3 dB, thereby increasing the expected detection rate by 40% (H1) and 50% (L1)

    A double-sided silicon micro-strip super-module for the ATLAS inner detector upgrade in the high-luminosity LHC

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    The ATLAS experiment is a general purpose detector aiming to fully exploit the discovery potential of the Large Hadron Collider (LHC) at CERN. It is foreseen that after several years of successful data-taking, the LHC physics programme will be extended in the so-called High-Luminosity LHC, where the instantaneous luminosity will be increased up to 5 × 1034 cm−2 s−1. For ATLAS, an upgrade scenario will imply the complete replacement of its internal tracker, as the existing detector will not provide the required performance due to the cumulated radiation damage and the increase in the detector occupancy. The current baseline layout for the new ATLAS tracker is an all-silicon-based detector, with pixel sensors in the inner layers and silicon micro-strip detectors at intermediate and outer radii. The super-module is an integration concept proposed for the strip region of the future ATLAS tracker, where double-sided stereo silicon micro-strip modules are assembled into a low-mass local support structure. An electrical super-module prototype for eight double-sided strip modules has been constructed. The aim is to exercise the multi-module readout chain and to investigate the noise performance of such a system. In this paper, the main components of the current super-module prototype are described and its electrical performance is presented in detail
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