429 research outputs found
Cosmic Ray Small Scale Anisotropies and Local Turbulent Magnetic Fields
Cosmic ray anisotropy has been observed in a wide energy range and at
different angular scales by a variety of experiments over the past decade.
However, no comprehensive or satisfactory explanation has been put forth to
date. The arrival distribution of cosmic rays at Earth is the convolution of
the distribution of their sources and of the effects of geometry and properties
of the magnetic field through which particles propagate. It is generally
believed that the anisotropy topology at the largest angular scale is
adiabatically shaped by diffusion in the structured interstellar magnetic
field. On the contrary, the medium- and small-scale angular structure could be
an effect of non-diffusive propagation of cosmic rays in perturbed magnetic
fields. In particular, a possible explanation of the observed small-scale
anisotropy observed at TeV energy scale, may come from the effect of particle
scattering in turbulent magnetized plasmas. We perform numerical integration of
test particle trajectories in low- compressible magnetohydrodynamic
turbulence to study how the cosmic rays arrival direction distribution is
perturbed when they stream along the local turbulent magnetic field. We utilize
Liouville's theorem for obtaining the anisotropy at Earth and provide the
theoretical framework for the application of the theorem in the specific case
of cosmic ray arrival distribution. In this work, we discuss the effects on the
anisotropy arising from propagation in this inhomogeneous and turbulent
interstellar magnetic field.Comment: 14 pages, 7 figures. Accepted for publication in Ap
Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems
(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.[EN] 3GPP has enhanced the point-to-multipoint
(PTM) communication capabilities of 4G LTE in all
releases since the adoption of eMBMS in Release-9.
Recent enhancements cover not only television services, but also critical machine-type and vehicular
communications, following the backward-compatibility design philosophy of LTE. This article discusses
the opportunity in the design and standardization
of 5G to break with the existing paradigm for PTM
transmissions in 4G LTE, where broadcast PTM
transmissions were initially conceived as an add-on
and pre-positioned service. 5G brings the opportunity to incorporate PTM capabilities as built-in delivery
features from the outset, integrating point-to-point
and PTM modes under one common framework
and enabling dynamic use of PTM to maximize network and spectrum efficiency. This approach will
open the door to completely new levels of network
management and delivery cost efficiency. The article
also discusses the implications of PTM for network
slicing to customize and optimize network resources
on a common 5G infrastructure to accommodate
different use cases and services taking into account
user densityThis work was supported in part by the European Commission under the 5G-PPP project Broadcast and Multicast Communication Enablers for the Fifth-(H2020-ICT-2016-2 call, grant number 761498).
The views expressed in this contribution are those
of the authors and do not necessarily represent
the project.Generation of Wireless Systems 5G-XcastGomez-Barquero, D.; Navratil, D.; Appleby, S.; Stagg, M. (2018). Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems. IEEE Communications Standards Magazine. 2(1):53-59. https://doi.org/10.1109/MCOMSTD.2018.170006953592
Non-invasive Estimation of Atrial Fibrillation Driver Position With Convolutional Neural Networks and Body Surface Potentials
[EN] Atrial fibrillation (AF) is characterized by complex and irregular propagation patterns, and AF onset locations and drivers responsible for its perpetuation are the main targets for ablation procedures. ECG imaging (ECGI) has been demonstrated as a promising tool to identify AF drivers and guide ablation procedures, being able to reconstruct the electrophysiological activity on the heart surface by using a non-invasive recording of body surface potentials (BSP). However, the inverse problem of ECGI is ill-posed, and it requires accurate mathematical modeling of both atria and torso, mainly from CT or MR images. Several deep learning-based methods have been proposed to detect AF, but most of the AF-based studies do not include the estimation of ablation targets. In this study, we propose to model the location of AF drivers from BSP as a supervised classification problem using convolutional neural networks (CNN). Accuracy in the test set ranged between 0.75 (SNR = 5 dB) and 0.93 (SNR = 20 dB upward) when assuming time independence, but it worsened to 0.52 or lower when dividing AF models into blocks. Therefore, CNN could be a robust method that could help to non-invasively identify target regions for ablation in AF by using body surface potential mapping, avoiding the use of ECGI.This work has been partially supported by: Ministerio de Ciencia e Innovacion (PID2019-105032GB-I00), Instituto de Salud Carlos III, and Ministerio de Ciencia, Innovacion y Universidades (supported by FEDER Fondo Europeo de Desarrollo Regional PI17/01106 and RYC2018-024346B-750), Consejeria de Ciencia, Universidades e Innovacion of the Comunidad de Madrid through the program RIS3 (S-2020/L2-622), EIT Health (Activity code 19600, EIT Health is supported by EIT, a body of the European Union) and the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 860974.Cámara-Vázquez, MÁ.; Hernández-Romero, I.; Morgado-Reyes, E.; Guillem Sánchez, MS.; Climent, AM.; Barquero-Pérez, O. (2021). Non-invasive Estimation of Atrial Fibrillation Driver Position With Convolutional Neural Networks and Body Surface Potentials. Frontiers in Physiology. 12:1-11. https://doi.org/10.3389/fphys.2021.733449S1111
Fusarium Wilt of Banana: Current Knowledge on Epidemiology and Research Needs Toward Sustainable Disease Management
Banana production is seriously threatened by Fusarium wilt (FW), a disease caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc). In the mid-twentieth century FW, also known as “Panama disease”, wiped out the Gros Michel banana industry in Central America. The devastation caused by Foc race 1 was mitigated by a shift to resistant Cavendish cultivars, which are currently the source of 99% of banana exports. However, a new strain of Foc, the tropical race 4 (TR4), attacks Cavendish clones and a diverse range of other banana varieties. Foc TR4 has been restricted to East and parts of Southeast Asia for more than 20 years, but since 2010 the disease has spread westward into five additional countries in Southeast and South Asia (Vietnam, Laos, Myanmar, India, and Pakistan) and at the transcontinental level into the Middle East (Oman, Jordan, Lebanon, and Israel) and Africa (Mozambique). The spread of Foc TR4 is of great concern due to the limited knowledge about key aspects of disease epidemiology and the lack of effective management models, including resistant varieties and soil management approaches. In this review we summarize the current knowledge on the epidemiology of FW of banana, highlighting knowledge gaps in pathogen survival and dispersal, factors driving disease intensity, soil and plant microbiome and the dynamics of the disease. Comparisons with FW in other crops were also made to indicate possible differences and commonalities. Our current understanding of the role of main biotic and abiotic factors on disease intensity is reviewed, highlighting research needs and futures directions. Finally, a set of practices and their impact on disease intensity are discussed and proposed as an integrative management approach that could eventually be used by a range of users, including plant protection organizations, researchers, extension workers and growers
The release of wastewater contaminants in the Arctic : a case study from Cambridge Bay, Nunavut, Canada
The treatment of municipal wastewater in the Arctic is challenging due to a variety of financial, operational, climatic and technical issues. To better understand the efficacy of current wastewater treatment in this region and the hazard posed to receiving waters, we assessed the occurrence of contaminants (i.e., pharmaceuticals, antibiotic resistance genes and nutrients) as they moved through a lagoon-based treatment system in Cambridge Bay in Nunavut, Canada. Wastewater treatment in this community is performed by the use of a lagoon-tundra wetland system that is discharged into the marine environment and is representative of current common practices throughout the region. In 2014, samples were collected before and during lagoon discharge from two locations in the main lagoon, one location downstream from the lagoon effluent and three locations offshore. Grab samples were collected to measure nutrients (e.g. total nitrogen and phosphorus) and the presence of antibiotic resistance gene-bearing microbes, and Polar Organic Chemical Integrative Samplers (POCIS) were deployed to collect passively organic contaminants in all locations. A total of six pharmaceuticals were detected from a screen of twenty-eight analytes during the study: atenolol, carbamazepine, clarithromycin, metoprolol, sulfamethoxazole and trimethoprim. The greatest concentrations of nutrients, antibiotic resistance genes (ARGs) and pharmaceuticals were found in sampling locations within the treatment lagoon. Offshore of the release point, we observed limited to no detection of pharmaceuticals and ARGs and no change in total nitrogen and phosphorus from pre-release. We conclude that the current concentrations of monitored pharmaceuticals do not pose a significant hazard at this time to aquatic organisms in Cambridge Bay
La entrevista estructurada en Psiquiatría.
Se analizan en este trabajo los fundamentos teóricos del proceso de estructuración de la entrevista psiquiátrica, así como las estrategias metodológicas seguidas para mejorar los niveles de fiabilidad del diagnóstico psiquiátrico. Para ello se toman como ejemplo las entrevistas psiquiátricas estructuradas o semi-estructuradas más significativas desarrolladas en los últimos años y que han tenido un especial impacto en nuestro país. Finalmente se presentan las entrevistas psiquiátricas de última generación (CIDI y SCAN) desarrolladas en el contexto de un programa multicéntrico internacional promovido por la OMS y la ADAMHA
La entrevista estructurada en Psiquiatría.
Se analizan en este trabajo los fundamentos teóricos del proceso de estructuración de la entrevista psiquiátrica, así como las estrategias metodológicas seguidas para mejorar los niveles de fiabilidad del diagnóstico psiquiátrico. Para ello se toman como ejemplo las entrevistas psiquiátricas estructuradas o semi-estructuradas más significativas desarrolladas en los últimos años y que han tenido un especial impacto en nuestro país. Finalmente se presentan las entrevistas psiquiátricas de última generación (CIDI y SCAN) desarrolladas en el contexto de un programa multicéntrico internacional promovido por la OMS y la ADAMHA
Admission to hospital following head injury in England: Incidence and socio-economic associations
BACKGROUND:
Head injury in England is common. Evidence suggests that socio-economic factors may cause variation in incidence, and this variation may affect planning for services to meet the needs of those who have sustained a head injury.
METHODS:
Socio-economic data were obtained from the UK Office for National Statistics and merged with Hospital Episodes Statistics obtained from the Department of Health. All patients admitted for head injury with ICD-10 codes S00.0–S09.9 during 2001–2 and 2002–3 were included and collated at the level of the extant Health Authorities (HA) for 2002, and Primary Care Trust (PCT) for 2003. Incidence was determined, and cluster analysis and multiple regression analysis were used to look at patterns and associations.
Results: 112,718 patients were admitted during 2001–2 giving a hospitalised incidence rate for England of 229 per 100,000. This rate varied across the English HA's ranging from 91–419 per 100,000. The rate remained unchanged for 2002–3 with a similar magnitude of variation across PCT's. Three clusters of HA's were identified from the 2001–2 data; those typical of London, those of the Shire counties, and those of Other Urban authorities. Socio-economic factors were found to account for a high proportion of the variance in incidence for 2001–2. The same pattern emerged for 2002–3 at the PCT level. The use of public transport for travel to work is associated with a
decreased incidence and lifestyle indicators, such as the numbers of young unemployed, increase the incidence.
CONCLUSION:
Head injury incidence in England varies by a factor of 4.6 across HA's and PCT's.
Planning head injury related services at the local level thus needs to be based on local incidence
figures rather than regional or national estimates. Socio-economic factors are shown to be
associated with admission, including travel to work patterns and lifestyle indicators, which suggests
that incidence is amenable to policy initiatives at the macro level as well as preventive programmes
targeted at key groups
Non-invasive clinical and microscopic evaluation of the response to treatment with clobetasol cream vs. calcipotriol/betamethasone dipropionate foam in mild to moderate plaque psoriasis : an investigator-initiated, phase IV, unicentric, open, randomized clinical trial
Treatment response for psoriasis is typically evaluated using clinical scores. However, patients can relapse after clinical clearance, suggesting persistent inflammation. Dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) can non-invasively improve treatment response assessment. To compare the clinical and non-invasive microscopic features in a psoriatic target lesion treated with clobetasol cream or calcipotriol/betamethasone dipropionate foam (Cal/BD foam). Prospective, unicentric, open, randomized clinical trial comparing clinical data [total clinical score (TCS)] and microscopic data (dermoscopy, RCM and OCT) in psoriasis patients treated with clobetasol or Cal/BD foam. We included 36 adult patients (22 men). At week 4, more patients treated with Cal/BD foam achieved TCS ≤1 than with clobetasol (63.2% vs. 18.8%, P = 0.016). Treatment satisfaction was higher with Cal/BD foam (P < 0.03). Microscopically, Cal/BD foam induced more reduction in epidermal thickness at week 4 (P < 0.049). Dilated horizontal blood vessels were more common with clobetasol than with Cal/BD foam at week 8 (69.2% vs. 31.2%, P = 0.159). If epidermal hyperplasia was noted at baseline, the response was poorer with clobetasol (P = 0.029). Small sample size, open study, imaging sampling bias. Cal/BD foam is more effective than clobetasol, has better patient satisfaction and induces greater reduction in the hyperkeratosis/acanthosis, regardless of baseline epidermal hyperplasia
Opportunities, Constraints and Perceptions of Rural Communities Regarding Their Potential to Contribute to Forest Landscape Transitions Under REDD+: Case Studies from Mexico
In Mexico, REDD+ is being presented as a win-win policy enabling forest communities to benefit financially and diversify their income sources while preserving and increasing their forest carbon stocks through more sustainable management. Under the national programme, it is expected that forest communities will have opportunities to tailor their own approaches. However, to date there is little understanding about what opportunities and constraints exist in reality for forest communities to contribute to REDD+, and even less about how their members perceive these opportunities. We assess potential and constraints at community level and investigate perceptions about opportunities in REDD+ and strategies that communities are currently envisaging for participation, in seven communities in the Ayuquila River Basin and around the Chamela-Cuixmala Biosphere Reserve in Jalisco, and in the area surrounding the Monarch Butterfly Reserve in Michoacan. We find that there is more opportunity for reduced degradation and forest enhancement than for reduced deforestation, in all the communities; that it may be difficult to establish additionality for REDD+ activities in some communities; that the amount of forest resource per community may greatly affect the potential to participate; that the presence of people with no land rights may complicate the distribution of benefits; that communities expect REDD+ in general to follow the Payment for Environmental Services model, and that lack of information about what activities may count as REDD+ activities and what level of financial rewards may be expected mean that communities cannot at present adequately appraise whether REDD+ will be worth their while or no
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