85 research outputs found

    Mapping Wide Row Crops with Video Sequences Acquired from a Tractor Moving at Treatment Speed

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    This paper presents a mapping method for wide row crop fields. The resulting map shows the crop rows and weeds present in the inter-row spacing. Because field videos are acquired with a camera mounted on top of an agricultural vehicle, a method for image sequence stabilization was needed and consequently designed and developed. The proposed stabilization method uses the centers of some crop rows in the image sequence as features to be tracked, which compensates for the lateral movement (sway) of the camera and leaves the pitch unchanged. A region of interest is selected using the tracked features, and an inverse perspective technique transforms the selected region into a bird’s-eye view that is centered on the image and that enables map generation. The algorithm developed has been tested on several video sequences of different fields recorded at different times and under different lighting conditions, with good initial results. Indeed, lateral displacements of up to 66% of the inter-row spacing were suppressed through the stabilization process, and crop rows in the resulting maps appear straight

    Arrhythmia and impaired myocardial function in heritable thoracic aortic disease: An international retrospective cohort study

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    Arrhythmia; Heritable thoracic aortic diseaseArritmia; Enfermedad hereditaria de la aorta torácicaArrítmia; Malaltia hereditària de l'aorta toràcicaBackground Heritable thoracic aortic diseases (HTAD), typically entailing aortic complications, can be caused by pathogenic variants or likely pathogenic variants (PV/LPVs) in several genes, including fibrillin1 (FBN1), Actin Alpha2 (ACTA2) and genes encoding components of the transforming growth factor (TGF)-β signaling pathway. In addition to aortic complications, non-aortic cardiac disease such as impaired myocardial function and/or arrhythmia have been increasingly reported, mainly in Marfan syndrome with underlying FBN1 PV/LPVs and are acknowledged as additional causes of morbidity and mortality. The prevalence of these manifestations in the various HTAD entities is largely unknown. Methods This international multicentre retrospective study collected data on patients with HTAD presenting non-aortic cardiac disease. A total of 9 centers from 7 different countries participated. Patients 12 years or older carrying a PV/LPV in one of the following genes: FBN1, TGFBR1, TGFBR2, TGFB2, TGFB3, SMAD3 and ACTA2 were screened. Non-aortic cardiac disease included impaired myocardial function and/or arrhythmia. Impaired myocardial function was defined as (a)symptomatic reduced ejection fraction (EF<50%). Arrhythmias included atrial fibrillation (AF), atrial flutter (AFL), ventricular tachycardia (VT), ventricular fibrillation (VF) and (aborted) sudden cardiac death (presumed arrhythmogenic) (SCD). Results Medical records of 3219 patients with HTAD were screened (2761, 385 and 73 carrying a PV/LPV in FBN1, in a TGF-β signaling gene and in ACTA2 respectively). Non-aortic cardiac disease was reported 142 times in 101 patients (3.1%) (age 37 [range 12–77] years, 39% female): 88 patients carrying an FBN1 PV/LPV and 13 carrying a PV/LPV in one of the TGF-β signaling genes. Neither impaired myocardial function nor arrhythmia was reported in screened patients carrying a PV/LPV in ACTA2. Among the 142 reported non-aortic cardiac diseases, 68 (48%) were impaired myocardial function, 47 (33%) were AF/AFL and 27 (19%) were VT/VF/SCD. Among the patients with non-aortic cardiac disease, prior cardiac surgery was noted in 80% and severe valvular disease (valvular surgery or severe valvular regurgitation) in 58%, while 18% of the patients developed non-aortic cardiac disease in the absence of any of the latter. Conclusions In patients with HTAD, arrhythmia and impaired myocardial function was reported in patients with PV/LPVs in FBN1 and in the TGF-β signaling genes and not in patients harboring PV/LPVs in ACTA2. Though infrequent, non-aortic cardiac disease should be acknowledged as potentially severe, also occurring in young patients with no underlying significant valvular or aortic disease

    Predictors of Ascending Aorta Enlargement and Valvular Dysfunction Progression in Patients with Bicuspid Aortic Valve

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    Aneurisma; Estenosis aórtica; Válvula aórtica bicúspideAneurisma; Estenosi aòrtica: Vàlvula aòrtica bicúspideAneurysm; Aortic stenosis; Bicuspid aortic valveBicuspid aortic valve (BAV) patients are at high risk of developing progressive aortic valve dysfunction and ascending aorta dilation. However, the progression of the disease is not well defined. We aimed to assess mid-long-term aorta dilation and valve dysfunction progression and their predictors. Patients were referred from cardiac outpatient clinics to the echocardiographic laboratories of 10 tertiary hospitals and followed clinically and by echocardiography for >5 years. Seven hundred and eighteen patients with BAV (median age 47.8 years [IQR 33–62], 69.2% male) were recruited. BAV without raphe was observed in 11.3%. After a median follow-up of 7.2 years [IQR5–8], mean aortic root growth rate was 0.23 ± 0.15 mm/year. On multivariate analysis, rapid aortic root dilation (>0.35 mm/year) was associated with male sex, hypertension, presence of raphe and aortic regurgitation. Annual ascending aorta growth rate was 0.43 ± 0.32 mm/year. Rapid ascending aorta dilation was related only to hypertension. Variables associated with aortic stenosis and regurgitation progression, adjusted by follow-up time, were presence of raphe, hypertension and dyslipidemia and basal valvular dysfunction, respectively. Intrinsic BAV characteristics and cardiovascular risk factors were associated with aorta dilation and valvular dysfunction progression, taking into account the inherent limitations of our study-design. Strict and early control of cardiovascular risk factors is mandatory in BAV patients

    An Image Segmentation Based on a Genetic Algorithm for Determining Soil Coverage by Crop Residues

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    Determination of the soil coverage by crop residues after ploughing is a fundamental element of Conservation Agriculture. This paper presents the application of genetic algorithms employed during the fine tuning of the segmentation process of a digital image with the aim of automatically quantifying the residue coverage. In other words, the objective is to achieve a segmentation that would permit the discrimination of the texture of the residue so that the output of the segmentation process is a binary image in which residue zones are isolated from the rest. The RGB images used come from a sample of images in which sections of terrain were photographed with a conventional camera positioned in zenith orientation atop a tripod. The images were taken outdoors under uncontrolled lighting conditions. Up to 92% similarity was achieved between the images obtained by the segmentation process proposed in this paper and the templates made by an elaborate manual tracing process. In addition to the proposed segmentation procedure and the fine tuning procedure that was developed, a global quantification of the soil coverage by residues for the sampled area was achieved that differed by only 0.85% from the quantification obtained using template images. Moreover, the proposed method does not depend on the type of residue present in the image. The study was conducted at the experimental farm “El Encín” in Alcalá de Henares (Madrid, Spain)

    Unraveling Bicuspid Aortic Valve Enigmas by Multimodality Imaging: Clinical Implications

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    Aortic aneurysm; Bicuspid aortic valve; Computed tomographyAneurisma aòrtic; Vàlvula aòrtica bicúspide; Tomografia computadaAneurisma aórtico; Válvula aórtica bicúspide; Tomografía computadaMultimodality imaging is the basis of the diagnosis, follow-up, and surgical management of bicuspid aortic valve (BAV) patients. Transthoracic echocardiography (TTE) is used in our clinical routine practice as a first line imaging for BAV diagnosis, valvular phenotyping and function, measurement of thoracic aorta, exclusion of other aortic malformations, and for the assessment of complications such are infective endocarditis and aortic. Nevertheless, TTE is less useful if we want to assess accurately other aortic segments such as mid-distal ascending aorta, where computed tomography (CT) and magnetic resonance (CMR) could improve the precision of aorta size measurement by multiplanar reconstructions. A major advantage of CT is its superior spatial resolution, which affords a better definition of valve morphology and calcification, accuracy, and reproducibility of ascending aorta size, and allows for coronary artery assessment. Moreover, CMR offers the opportunity of being able to evaluate aortic functional properties and blood flow patterns. In this setting, new developed sequences such as 4D-flow may provide new parameters to predict events during follow up. The integration of all multimodality information facilitates a comprehensive evaluation of morphologic and dynamic features, stratification of the risk, and therapy guidance of this cohort of patients

    Are Aortic Root and Ascending Aorta Diameters Measured by the Pediatric versus the Adult American Society of Echocardiography Guidelines Interchangeable?

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    Aortic dimensions; Echocardiography; Guideline’s recommendationsDimensions aòrtiques; Ecocardiografia; Recomanacions de les directriusDimensiones aórticas; Ecocardiografía; Recomendaciones de las directricesAscending aorta diameters have important clinical value in the diagnosis, follow-up, and surgical indication of many aortic diseases. However, there is no uniformity among experts regarding ascending aorta diameter quantification by echocardiography. The aim of this study was to compare maximum aortic root and ascending aorta diameters determined by the diastolic leading edge (DLE) and the systolic inner edge (SIE) conventions in adult and pediatric patients with inherited cardiovascular diseases. Transthoracic echocardiograms were performed in 328 consecutive patients (260 adults and 68 children). Aorta diameters were measured twice at the root and ascending aorta by the DLE convention following the 2015 American Society of Echocardiography (ASE) adult guidelines and the SIE convention following the 2010 ASE pediatric guidelines. Comparison of the diameters measured by the two conventions in the overall population showed a non-significant underestimation of the diameter measured by the SIE convention at root level of 0.28 mm (CI −1.36; 1.93) and at tubular ascending aorta level of 0.17 mm (CI −1.69; 2.03). Intraobserver and interobserver variability were excellent. Maximum aorta diameter measured by the leading edge convention in end-diastole and the inner edge convention in mid-systole had similar values to a mild non-significant underestimation of the inner-to-inner method that permits them to be interchangeable when used in clinical practice

    Effects of Combined CCR5/Integrase Inhibitors-Based Regimen on Mucosal Immunity in HIV-Infected Patients Naïve to Antiretroviral Therapy: A Pilot Randomized Trial

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    Whether initiation of antiretroviral therapy (ART) regimens aimed at achieving greater concentrations within gut associated lymphoid tissue (GALT) impacts the level of mucosal immune reconstitution, inflammatory markers and the viral reservoir remains unknown. We included 12 HIV- controls and 32 ART-naïve HIV patients who were randomized to efavirenz, maraviroc or maraviroc+raltegravir, each with fixed-dose tenofovir disoproxil fumarate/emtricitabine. Rectal and duodenal biopsies were obtained at baseline and at 9 months of ART. We performed a comprehensive assay of T-cell subsets by flow cytometry, T-cell density in intestinal biopsies, plasma and tissue concentrations of antiretroviral drugs by high-performance liquid chromatography/mass spectroscopy, and plasma interleukin-6 (IL-6), lipoteichoic acid (LTA), soluble CD14 (sCD14) and zonulin-1 each measured by ELISA. Total cell-associated HIV DNA was measured in PBMC and rectal and duodenal mononuclear cells. Twenty-six HIV-infected patients completed the follow-up. In the duodenum, the quadruple regimen resulted in greater CD8+ T-cell density decline, greater normalization of mucosal CCR5+CD4+ T-cells and increase of the naïve/memory CD8+ T-cell ratio, and a greater decline of sCD14 levels and duodenal HIV DNA levels (P = 0.004 and P = 0.067, respectively), with no changes in HIV RNA in plasma or tissue. Maraviroc showed the highest drug distribution to the gut tissue, and duodenal concentrations correlated well with other T-cell markers in duodenum, i.e., the CD4/CD8 ratio, %CD4+ and %CD8+ HLA-DR+CD38+ T-cells. Maraviroc use elicited greater activation of the mucosal naïve CD8+ T-cell subset, ameliorated the distribution of the CD8+ T-cell maturational subsets and induced higher improvement of zonulin-1 levels. These data suggest that combined CCR5 and integrase inhibitor based combination therapy in ART treatment naïve patients might more effectively reconstitute duodenal immunity, decrease inflammatory markers and impact on HIV persistence by cell-dependent mechanisms, and show unique effects of MVC in duodenal immunity driven by higher drug tissue penetration and possibly by class-dependent effects

    Role of B Cell Profile for Predicting Secondary Autoimmunity in Patients Treated With Alemtuzumab

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    UDHEBRONTo explore if baseline blood lymphocyte profile could identify relapsing remitting multiple sclerosis (RRMS) patients at higher risk of developing secondary autoimmune adverse events (AIAEs) after alemtuzumab treatment. Multicenter prospective study including 57 RRMS patients treated with alemtuzumab followed for 3.25 [3.5-4.21] years, (median [interquartile range]). Blood samples were collected at baseline, and leukocyte subsets determined by flow cytometry. We had additional samples one year after the first cycle of alemtuzumab treatment in 39 cases. Twenty-two patients (38.6%) developed AIAEs during follow-up. They had higher B-cell percentages at baseline (p=0.0014), being differences mainly due to plasmablasts/plasma cells (PB/PC, p=0.0011). Those with no AIAEs had higher percentages of CD4+ T cells (p=0.013), mainly due to terminally differentiated (TD) (p=0.034) and effector memory (EM) (p=0.031) phenotypes. AIAEs- patients also showed higher values of TNF-alpha-producing CD8+ T cells (p=0.029). The percentage of PB/PC was the best variable to differentiate both groups of patients. Baseline values >0.10% closely associated with higher AIAE risk (Odds ratio [OR]: 5.91, 95% CI: 1.83-19.10, p=0.004). When excluding the 12 patients with natalizumab, which decreases blood PB/PC percentages, being the last treatment before alemtuzumab, baseline PB/PC >0.1% even predicted more accurately the risk of AIAEs (OR: 11.67, 95% CI: 2.62-51.89, p=0.0007). The AIAEs+ group continued having high percentages of PB/PC after a year of alemtuzumab treatment (p=0.0058). A PB/PC percentage <0.1% at baseline identifies MS patients at low risk of secondary autoimmunity during alemtuzumab treatment.

    Towards the Integration of Higher Airspace Operations in the European ATM Network

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    While very limited HAO are supported today by existing ATM processes, owing to innovation the number of operations is expected to grow substantially in the coming years. This will involve different geographical distributions and types of vehicles, ranging from slow moving HAPS to very high-speed vehicles. New entrants will provide new challenges in terms of flight-performance envelopes, operating at level bands not used today and where their operational behavior and performance may generate additional uncertainty in ATM. Therefore, the major challenge is to research new solutions needed for a safe, fair and effective integration of the new entrants in the new operational environment by providing validated flight trajectories, procedural packages for both nominal and contingency scenarios and real time monitoring capability. This paper presents principles, assumptions and concept elements for the integration of HAO in Europe, which have been developed during the SESAR project European Concept for Higher Airspace operations (ECHO)
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