175 research outputs found

    Exploring RCNN for the automated analysis of paramagnetic rim lesions in Multiple Sclerosis MRI

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    In multiple sclerosis, lesions with a peripheral paramagnetic rim is a negative prognostic imaging biomarker and represents a potential outcome measure in MRI-based clinical trials. Nowadays, the presence or absence of paramagnetic rims is determined through visual inspection by medical experts, which is tedious, time consuming and prone to observer variability. So far, few solutions to the automated classification of rims problem have been proposed. These studies present limitations that represent an obstacle to full automation of the rim analysis process and its large-scale application. Our goal is to implement and assess a fully automated algorithm capable of identifying rim lesions in MRI. In this work, we explore a Region-proposal CNN deep learning approach to solve the fully automated rim lesions classification problem that perform instance segmentation by object detection and have shown promising results in recent challenges, particularly in medical imaging. After different approaches focus on implifying the task, Mask RCNN with MobileNet v2 as backbone using attention gaussian filtering to the input images showed better performance than the rest with rates of 0.42 TPR and 0.61 FPR for the test set. However, the achieved results reveal the weaknesses of our approach and the difficulty of our classification problem

    C. elegans epigenetic regulation in development and aging

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License.The precise developmentalmap of the Caenorhabditis elegans cell lineage, as well as a complete genome sequence and feasibility of genetic manipulation make this nematode species highly attractive to study the role of epigenetics during development. Genetic dissection of phenotypical traits, such as formation of egg-laying organs or starvation- resistant dauer larvae, has illustrated how chromatin modifiers may regulate specific cell-fate decisions and behavioral programs. Moreover, the transparent body of C. elegans facilitates non-invasive microscopy to study tissue-specific accumulation of heterochromatin at the nuclear periphery. We also review here recent findings on how small RNA molecules contribute to epigenetic control of gene expression that can be propagated for several generations and eventually determine longevity.This work was supported by the CNRS [to F.P.]; Fondation ARC [SFI20101201659 to F.P.]; Ligue Contre le Cancer [to F.P.]; the Spanish Ministry of Economy and Competitiveness [BFU2010-15478 to P.A.]; the Autonomous Government of Andalusia [P08-CVI-3920 to P.A.]; and the European Regional Development Fund.Peer Reviewe

    Geophysical exploration for shallow geothermal applications: A case study in ArtĂ , (Balearic Islands, Spain)

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    [EN] Within the installation of a shallow geothermal system, the lack of information on the subsoil frequently leads to errors in the design of the geothermal wellfield. This research presents the application of geophysics, combining 2D and 3D electrical resistivity tomography surveys and the geological information of a certain area for defining the structural distribution of the underground. Processed electrical resistivity data allow elucidating possible geological units and the thermal behavior of the in-depth materials. Two different assumptions (with different locations of the wells) are designed by using the specific geothermal software GES-CAL. Results show, that Case 1 (based on the geophysical results, so avoiding complex areas) allows the reduction of the global drilling length, and hence, the general initial investment of the system (around 20% lower). Meanwhile, Case 2 (without considering the geophysics) is less economically advantageous and could also present technical difficulties during the drilling process, as well as the possible alteration to the normal system operation. The study highlights the benefits of geophysics as an effective approach to characterize the underground and to help to understand its thermal behavior, which is, in turn, crucial for a proper geothermal design.S

    Investigating the potential of the slurry technology for sustainable pig farm heating

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    Sustainable energy development in the farming sector is an essential strategy to respond the combined challenge of achieving a reliable and affordable solution but including mitigation and adaptation to climate change. Intensive breeding farms require maintaining an adequate indoor thermal environment that results in high energy demands, usually covered by fossil fuels and electricity. This paper addresses the application of the combined slurry technology for a particular pig farm that currently uses a diesel boiler to supply the piglet heating energy needs. The study also considers different options based on closed ground source heat pump systems. After the design of the slurry alternative and the geothermal ones, notable advantages are detected compared to the existing diesel system. Results show that the implementation of the slurry technology implies an important reduction of the operational costs, which, in turn, involves short amortization periods for this system in relation to the diesel one. Greenhouse gases emissions are also highly reduced in the slurry alternative based on the low electricity use of the heat pump. The environmental side is reinforced by the reduction of polluting substances such as methane of ammonia derived from the descent of temperature of the slurry

    Geophysical Prospecting for Geothermal Resources in the South of the Duero Basin (Spain)

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    [EN]The geothermal resources in Spain have been a source of deep research in recent years and are, in general, well-defined. However, there are some areas where the records from the National Institute for Geology and Mining show thermal activity from different sources despite no geothermal resources being registered there. This is the case of the area in the south of the Duero basin where this research was carried out. Seizing the opportunity of a deep borehole being drilled in the location, some geophysical resources were used to gather information about the geothermal properties of the area. The employed geophysical methods were time-domain electromagnetics (TDEM) and borehole logging; the first provided information about the depth of the bedrock and the general geological structure, whereas the second one gave more detail on the geological composition of the different layers and a temperature record across the whole sounding. The results allowed us to establish the geothermal gradient of the area and to discern the depth of the bedrock. Using the first 200 m of the borehole logging, the thermal conductivity of the ground for shallow geothermal systems was estimated

    Inflammatory markers and bone mass in children with overweight/obesity: the role of muscular fitness

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    Objectives To examine which inflammatory markers are associated with bone mass and whether this association varies according to muscular fitness in children with overweight/obesity. Methods Plasma interleukin-1ÎČ (IL-1ÎČ), IL-6, tumor necrosis factor-α (TNF-α), epidermal growth factor, vascular endothelial growth factor A (VEGF), and C-reactive protein were analyzed in 55 children aged 8–11 years. A muscular fitness score was computed. Bone mineral content (BMC) of the total body-less head (TBLH) and lumbar spine (LS) were assessed using dual-energy x-ray absorptiometry. Results IL-6 (ÎČ = −0.136) and VEGF (ÎČ = −0.099) were associated with TBLH BMC, while TNF-α (ÎČ = −0.345) and IL-1ÎČ (ÎČ = 0.212) were associated with LS BMC (P < 0.05). The interaction effect of muscular fitness showed a trend in the association of VEGF with TBLH BMC (P = 0.122) and TNF-α with LS BMC (P = 0.057). Stratified analyses by muscular fitness levels showed an inverse association of VEGF with TBLH BMC (ÎČ = −0.152) and TNF-α with LS BMC (ÎČ = −0.491) in the low-fitness group, while no association was found in the high-fitness group. Conclusion IL-6, VEGF, TNF-α, and IL-1ÎČ are significantly associated with bone mass. Higher muscular fitness may attenuate the adverse effect of high VEGF and TNF-α on bone mass

    Use of 3D electrical resistivity tomography to improve the design of low enthalpy geothermal systems

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    [EN] In designing low enthalpy geothermal systems, the ideal location and length of the boreholes in the well-field is the key to improve the performance and reduce the costs of the installation. The correct assessment of the heat conductivity of the ground (λ) plays also a very important role in estimating the amount of energy that we are going to be able to obtain from the subsoil and the ideal pace of the process. In low enthalpy geothermal installations based on granite type environments is especially important to improve the information we have from the subsoil at a small scale. This is due to the great horizontal variation we can find on this kind of terrain. Electrical conductivity (C = 1/ρ, ρ = resistivity in ohm meters) can be related to thermal conductivity (λ) of many rock types (Directive (EU), 2019) (see Robertson, 1988). We show that a 3D electrical resistivity survey can be used as a proxy for λ in terrain with weathered and solid granitic rock. Knowledge of λ is essential for the design of efficient ground source heat pump systems that use vertical wells for closed-loop systems. Shorter well lengths are accomplished if wells are in solid granite with high λ. Furthermore the electrical resistivity survey identifies low density, clayey subsurface materials that may require specialized drilling methods. Project cost savings can result from shorter borehole lengths, number of holes, and correct drilling methods

    Benefits of oral Polypodium Leucotomos extract in MM high-risk patients

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    Background: UV radiation and the presence of melanocytic nevi are the main risk factors of sporadic melanoma (MM). Protection of skin by an oral photoprotective agent would have substantial benefits. Objective: We investigated the possible role of an oral Polypodium leucotomos (PL) extract to improve systemic photoprotection in patients at risk of skin cancer analyzing the ability to decrease UV‐induced erythema. We also studied the interaction among MC1R polymorphisms and CDKN2A status with the minimal erythematous dose (MED) and their influence in the response after oral PL. Methods: A total of 61 patients (25 with familial and/or multiple MM, 20 with sporadic MM and 16 with atypical mole syndrome without history of MM) were exposed to varying doses of artificial UVB radiation without and after oral administration of a total dose of 1080mg of PL. Results: Oral PL treatment significantly increased the MED mean in all group patients (0.123 to 0.161 J/cm2, p<0.05). Although not significant, we noticed a stronger effect of PL on the MED of patients with familial MM compared to those with MM (U=273, p=0.06). Among the patients with familial MM, those exhibiting a mutated CDKN2A and/or polymorphisms in MC1R had the bigger differences in response to treatment with PL. Limitations: Reduced number of patients. No control population. Conclusions: Administration of PL leads to a significant reduction of sensitivity to UVR (p<0.05) in all patients. Dark‐eye patients and patients with higher UVR sensibility (lower basal MED) would be the most benefited from oral PL treatment
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