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Who counts and who is counted? Conversations around voting, access, and divisions in the disability community
Online voting platforms have been introduced in some locations as the solution to the many barriers to political participation that disabled people continue to face. Reading the experiences of disabled student voters on university campuses alongside broader trends in electoral reform taking place in jurisdictions across Canada allows us to attend to the dangerous ways in which conversations around access have been limited through virtual solutions that encourage the physical absence of disabled voters. This article situates these absences alongside other categories of exclusionâincluding groups who are formally disenfranchisedâand recalls many unstated values that are active in shaping citizenship cultures. Probing online voting through a critical disability angle, we present a critique of techno-fixes that builds upon broader notions of accessibility and inclusion
Preliminary estimates of tritium permeation and retention in the first wall of DEMO due to ion bombardment
Tritium self-sufficiency presents a critical engineering challenge for DEMO, requiring efficient breeding and extraction systems, as well as minimizing tritium losses to the surrounding systems, such as plasma-facing components, vacuum vessel, cooling system, etc. Structural and plasma-facing components will act as a tritium sink, as tritium will be accumulated in the bulk of these components due to energetic particle bombardment and may permeate out of the vacuum system. The design of the plasma-facing components will consequently directly influence the plant lifetime, operational safety and cost of any future power plant. Therefore, modeling of tritium retention and permeation in these components is required for the engineering designs of the tritium breeding and safety systems. In this work, the diffusion-transport code TESSIM-X is benchmarked against the well-established TMAP7 code and a comparison with a simplified DEMO-relevant test case is performed. The use of either code for modeling of DEMO conditions is discussed. Following this, TESSIM-X is used to provide a preliminary assessment of tritium permeation and retention in the DEMO first wall, based on the current WCLL (Water Cooled Lithium Lead) and HCPB (Helium Cooled Pebble Bed) breeding blanket designs
Fluid pressurisation and earthquake propagation in the Hikurangi subduction zone
In subduction zones, seismic slip at shallow crustal depths can lead to the generation of tsunamis. Large slip displacements during tsunamogenic earthquakes are attributed to the low coseismic shear strength of the fluid-saturated and non-lithified clay-rich fault rocks. However, because of experimental challenges in confining these materials, the physical processes responsible for the coseismic reduction in fault shear strength are poorly understood. Using a novel experimental setup, we measured pore fluid pressure during simulated seismic slip in clay-rich materials sampled from the deep oceanic drilling of the PÄpaku thrust (Hikurangi subduction zone, New Zealand). Here, we show that at seismic velocity, shear-induced dilatancy is followed by pressurisation of fluids. The thermal and mechanical pressurisation of fluids, enhanced by the low permeability of the fault, reduces the energy required to propagate earthquake rupture. We suggest that fluid-saturated clay-rich sediments, occurring at shallow depth in subduction zones, can promote earthquake rupture propagation and slip because of their low permeability and tendency to pressurise when sheared at seismic slip velocities
Application of a score system to evaluate the risk of malnutrition in a multiple hospital setting
Background: An increased but unpredictable risk of malnutrition is associated with hospitalization, especially in children with chronic diseases. We investigated the applicability of Screening Tool for Risk of Impaired Nutritional Status and Growth (STRONGkids), an instrument proposed to estimate the risk of malnutrition in hospitalized children. We also evaluated the role of age and co-morbidities as risk for malnutrition. Methods. The STRONGkids consists of 4 items providing a score that classifies a patient in low, moderate, high risk for malnutrition. A prospective observational multi-centre study was performed in 12 Italian hospitals. Children 1-18 years consecutively admitted and otherwise unselected were enrolled. Their STRONGkids score was obtained and compared with the actual nutritional status expressed as BMI and Height for Age SD-score. Results: Of 144 children (75 males, mean age 6.5 \ub1 4.5 years), 52 (36%) had an underlying chronic disease. According to STRONGkids, 46 (32%) children were at low risk, 76 (53%) at moderate risk and 22 (15%) at high risk for malnutrition. The latter had significantly lower Height for Age values (mean SD value -1.07 \ub1 2.08; p = 0.008) and BMI values (mean SD-values -0.79 \ub1 2.09; p = 0.0021) in comparison to other groups. However, only 29 children were actually malnourished. Conclusions: The STRONGkids is easy to administer. It is highly sensitive but not specific. It may be used as a very preliminary screening tool to be integrated with other clinical data in order to reliably predict the risk of malnutrition. \ua9 2013 Spagnuolo et al.; licensee BioMed Central Ltd
Variability of kinematic source parameters and its implication on the choice of the design scenario
Near-fault seismic recordings for recent earthquakes (Chi Chi earthquake,
1999, and Parkfield earthquake, 2004) show the high spatial heterogeneity
of ground motion. This variability is controlled by fault geometry, rupture complexity,
and also by wave propagation and site effects. Nowadays, the number of available
records in the near-source region is still not enough to infer a robust parameterization
of the ground motion and to retrieve multiparametric predictive equations valid at
close distances from the fault. The use of a synthetic approach may help to overcome
this limitation and to study the strong ground motion variability. In this article we
focus on ground-motion dependence on different earthquakes breaking the same fault,
as it has been rarely recorded by instruments. We model seismic scenarios from different
rupture models of a fault similar to the 1980 Irpinia, Italy, earthquake source
(Mw 6.9). A discrete wavenumber/finite element technique is used to compute fullwave
displacement and velocity time series in the low-frequency band (up to 2 Hz).
We investigate the variability of the ground motion as a function of different
source parameters (rupture velocity, slip distribution, nucleation point, and source
time function), whose values depend on the state of knowledge of the physical model
driving the process. The probability density functions of the simulated ground-motion
parameters, such as displacement response spectrum and peak ground velocity, are
used to identify particular scenarios that match specific engineering requests
Polyphenols as potential agents in the management of temporomandibular disorders
Temporomandibular disorders (TMD) consist of multifactorial musculoskeletal disorders associated with the muscles of mastication, temporomandibular joint (TMJ), and annexed structures. This clinical condition is characterized by temporomandibular pain, restricted mandibular movement, and TMJ synovial inflammation, resulting in reduced quality of life of affected people. Commonly, TMD management aims to reduce pain and inflammation by using pharmacologic therapies that show efficacy in pain relief but their long-term use is frequently associated with adverse effects. For this reason, the use of natural compounds as an effective alternative to conventional drugs appears extremely interesting. Indeed, polyphenols could represent a potential therapeutic strategy, related to their ability to modulate the inflammatory responses involved in TMD. The present work reviews the mechanisms underlying inflammation-related TMD, highlighting the potential role of polyphenols as a promising approach to develop innovative management of temporomandibular diseases
Coordination and spin state equilibria as a function of pH, ionic strength, and protein concentration in oxidized dimeric Scapharca inaequivalvis hemoglobin.
The oxidized homodimeric Scapharca inaequivalvis hemoglobin undergoes changes in coordination and spin state as a function of pH, ionic strength, and protein concentration which have been monitored by optical absorption spectroscopy. Three species contribute to the spectra between pH 5.8 and 8.7: (i) a hexacoordinate high spin aquomet derivative, whose concentration is essentially constant over the whole pH range analyzed; (ii) a pentacoordinate high spin component which prevails at alkaline pH values, and (iii) a hexacoordinate low spin hemichrome, which is formed at acid pH. The contribution of each of the components to the observed spectra was calculated with the singular value decomposition procedure and has been described quantitatively in terms of a linkage scheme which accounts for the change in heme coordination and for the observation that the high spin to low spin transition entails dissociation into monomers. An important feature of the linkage scheme is the cooperative binding of protons to aquomet dimers. Stopped flow experiments to study the kinetics indicate that dissociation into monomers is the rate-limiting process. The unusually strong tendency of oxidized HbI to loose the heme-bound water molecule is discussed in terms of strain in the iron-proximal histidine bond
Clinical application and technical standardization of indocyanine green (ICG) fluorescence imaging in pediatric minimally invasive surgery
Purpose We reported our preliminary experience using ICG fluorescence in pediatric minimally invasive surgery (MIS) with the aim to standardize indications, dose, timing, and modality of administration of ICG according to different organs. Methods ICG technology was adopted in 46 MIS procedures performed in our unit over the last 18 months: 30 left varicocele repairs; 5 cholecystectomies in obese adolescents; 3 tumor excisions; 3 nephrectomies; 2 partial nephrectomies; 3 lymphoma excisions. ICG solution was injected intravenously in all cases except for varicocelectomy in which it was injected into the testis. The ICG injection was performed intra-operatively in all cases except for cholecystectomy in which it was injected 18 h prior to the procedure. Results All procedures were completed laparoscopically without conversions or intra-operative complications. No adverse or allergic reactions to ICG were reported. Conclusion Our preliminary experience showed that ICG fluorescence is a safe, useful, and versatile technique to adopt in pediatric MIS to achieve a better identification of anatomy and an easier surgical dissection or resection in challenging cases. Currently, the main indications are varicocelectomy, difficult cholecystectomy, tumor excision, nephrectomy, and partial nephrectomy. The main limitation is the needing of a special equipment to use ICG technology
Minimization of Adverse Effects Associated with Dental Alloys
Metal alloys are one of the most popular materials used in current dental practice. In the oral cavity, metal structures are exposed to various mechanical and chemical factors. Consequently, metal ions are released into the oral fluid, which may negatively affect the surrounding tissues and even internal organs. Adverse effects associated with metallic oral appliances may have various local and systemic manifestations, such as mouth burning, potentially malignant oral lesions, and local or systemic hypersensitivity. However, clear diagnostic criteria and treatment guidelines for adverse effects associated with dental alloys have not been developed yet. The present comprehensive literature review aims (1) to summarize the current information related to possible side effects of metallic oral appliances; (2) to analyze the risk factors aggravating the negative effects of dental alloys; and (3) to develop recommendations for diagnosis, management, and prevention of pathological conditions associated with metallic oral appliances
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