The stationary wavelet transform as an efficient reductor of powerline interference for atrial bipolar electrograms in cardiac electrophysiology

[EN] Objective :The most relevant source of signal contamination in the cardiac electrophysiology (EP) laboratory is the ubiquitous powerline interference (PLI). To reduce this perturbation, algorithms including common fixed-bandwidth and adaptive-notch filters have been proposed. Although such methods have proven to add artificial fractionation to intra-atrial electrograms (EGMs), they are still frequently used. However, such morphological alteration can conceal the accurate interpretation of EGMs, specially to evaluate the mechanisms supporting atrial fibrillation (AF), which is the most common cardiac arrhythmia. Given the clinical relevance of AF, a novel algorithm aimed at reducing PLI on highly contaminated bipolar EGMs and, simultaneously, preserving their morphology is proposed. Approach: The method is based on the wavelet shrinkage and has been validated through customized indices on a set of synthesized EGMs to accurately quantify the achieved level of PLI reduction and signal morphology alteration. Visual validation of the algorithm¿s performance has also been included for some real EGM excerpts. Main results: The method has outperformed common filtering-based and wavelet-based strategies in the analyzed scenario. Moreover, it possesses advantages such as insensitivity to amplitude and frequency variations in the PLI, and the capability of joint removal of several interferences. Significance: The use of this algorithm in routine cardiac EP studies may enable improved and truthful evaluation of AF mechanisms.Research supported by grants DPI2017-83952-C3 MINECO/AEI/FEDER, UE and SBPLY/17/180501/000411 from Junta de Comunidades de Castilla-La Mancha.Martinez-Iniesta, M.; Ródenas, J.; Rieta, JJ.; Alcaraz, R. (2019). 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Analysis of soil texture using terrasar x-band sar

International audienceIn this paper, it is proposed to use TERRASAR-X data for analysis and estimation of soil surface texture. Our study is based on experimental campaigns carried out over a semi-arid area in North Africa. Simultaneously to TERRASAR-X radar acquisitions, ground measurements (texture, soil moisture and roughness) were made on different test fields. A strong correlation is observed between soil texture and a processed signal from two radar images, the first acquired just after a rain event and the second corresponding to dry soil conditions, acquired three weeks later. An empirical relationship is proposed for the retrieval from radar signals of clay content percent. Soil texture mapping is proposed over the study site, which includes bare soils and olive groves

In vitro efficacy of some plant aqueous extracts against two species of Lasiodiplodia associated to mango decline in Burkina Faso

Mango decline is a serious disease in production areas in Burkina Faso. The aim of this study was to contribute to the management of the disease through the use of plant aqueous extracts. Antifungal activities of Azadirachta indica, Calotropis procera, Gmelina arborea, Jatropha curcas, Eucalyptus camaldulensis and the synthetic fungicide (Mancozeb) were tested against Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae associated to mango decline in Burkina Faso. Three different concentrations of leaf extracts which 25%, 50%, 75% and 500 ppm of Mancozeb were tested for their antifungal activity in vitro. The results showed that leaf extracts have an inhibitor effect on the growth of the two Lasiodiplodia species. The aqueous extract of G. arborea was the most effective with average inhibition rates of L. theobromae of 42.62%, 73.84% and 74.23% respectively with the concentrations of 25 g/l, 50 g/l and 75 g/l. The aqueous extract of A. indica against L. pseudotheobromae showed maximum percentage inhibition with 50 g/l of 63.10% and with 75 g/l of 72.02%. Mancozeb completely inhibits the mycelial growth of both species of fungi. Ours findings showed that aqueous extracts from plants could be tried for the eco-friendly management of mango decline pathogens.Keywords: Antifungal, plants extract, Lasiodiplodia spp., mango decline, Burkina Faso

Effets des Amendements Organiques sur la Gale Bactérienne et la Pourriture Apicale de la Tomate à Bobo-Dioulasso au Burkina Faso

L’étude a porté sur les effets des amendements organiques sur la gale bactérienne et la pourriture apicale de la tomate en milieu réel à l’Ouest du Burkina Faso. Un essai a été mis en place dans un dispositif en bloc de Fisher complètement randomisé. Il a comporté huit (08) traitements constitués des fertilisants organiques et minéraux tous répétés quatre (04) fois. L’incidence de la maladie et sa sévérité ont été évaluées ainsi que l’effet des traitements sur la qualité des fruits. La progression est relativement faible avec les déchets ménagers compostés associés aux engrais minéraux. La maladie est plus sévère avec les différents fertilisants pris individuellement. Dans l’ensemble, la maladie est évolutive avec tous les traitements.   The study focused on the effects of organic amendments on bacterial scab and apical rot of tomato in a real environment in western Burkina Faso. Indeed, a trial was set up in a completely randomized Fisher block design. It included eight (08) treatments consisting of organic and mineral fertilizers all repeated four (04) times. The incidence of the disease and its severity were evaluated as well as the effect of the treatments on the quality of the fruits. The disease is progressive with all treatments. However, the progression is relatively low with composted household waste associated with mineral fertilizers. The disease is more severe with the different fertilizers taken individually

MYOD-1 in normal colonic mucosa : role as a putative biomarker?

Background DNA methylation of promoter-associated CpG islands of certain genes may play a role in the development of colorectal cancer. The MYOD-1 gene which is a muscle differentiation gene has been showed to be significantly methylated in colorectal cancer which, is an age related event. However the role of this gene in the colonic mucosa is not understood and whether methylation occurs in subjects without colon cancer. In this study, we have determined the frequency of methylation of the MYOD-1 gene in normal colonic mucosa and investigated to see if this is associated with established colorectal cancer risk factors primarily ageing. Results We analysed colonic mucosal biopsies in 218 normal individuals and demonstrated that in most individuals promoter hypermethylation was not quantified for MYOD-1. However, promoter hypermethylation increased significantly with age (p < 0.001 using regression analysis) and this was gender independent. We also showed that gene promoter methylation increased positively with an increase in waist to hip (WHR) ratio – the latter is also a known risk factor for colon cancer development. Conclusions Our study suggests that promoter gene hypermethylation of the MYOD-1 gene increases significantly with age in normal individuals and thus may offer potential as a putative biomarker for colorectal cancer

Arthroscopic Treatment of Shoulder Stiffness with Rotator Cuff Repair Yields Similar Outcomes to Isolated Rotator Cuff Repair

Purpose: To compare patient-reported and surgical outcome measures in patients with and without secondary shoulder stiffness (SSS) undergoing rotator cuff repair (RCR). Methods: Patients undergoing rotator cuff repair from 2014 to 2020 with complete patient-reported outcome measures (PROMs) by the short-form 12 survey (SF-12) were retrospectively reviewed to identify if operative intervention for SSS was performed alongside the RCR. Those patients with operative intervention for SSS were propensity matched to a group without prior intervention for stiffness by age, sex, laterality, body mass index, diabetes mellitus status, and the presence of a thyroid disorder. The groups were compared by rotator cuff tear (RCT) size, surgical outcomes, further surgical intervention, rotator cuff retear rate, postoperative range of motion (ROM), and SF-12 results at one year after surgery. Delta values were calculated for component scores of the SF-12 and ROM values by subtracting the preoperative result from the postoperative result. Results: A total of 89 patients with SSS were compared to 156 patients in the control group at final analysis. SSS group experienced a significant improvement by the delta mental health component score (MCS-12) of the SF-12 survey that was not seen in the control group (p=0.005 to p=0.539). Both groups experienced significant improvement by the delta physical health component score (PCS-12) of the SF-12 survey (SSS: 7.68, p\u3c0.001; control: 6.95, p\u3c0.001). The SSS group also experienced greater improvement of their forward flexion (25.80 vs 12.9°, p-0.005) and external rotation (7.13° vs 1.65°, p=0.031) ROM than the control group. Conclusions: Operative intervention of SSS at the time of RCR has equivalent postoperative outcomes by the SF-12 survey when compared to patients undergoing RCR without preoperative stiffness

Gestion durable des terres agricoles dans la commune rurale de Sanankoroba, cercle de Kati

Summary The rural commune of Sanankororba located in the circle of Kati in Mali, is characterized by a very great diversity of natural ecosystems, which host resources such as soil, vegetation, water. These elements constitute the main wealth of the commune whose agricultural activities occupy the majority of the population and provide them with the essential of their means of existence. However, for several decades, there has been a continuous degradation of agricultural land mainly due to demographic pressure, harmful agricultural practices and climatic hazards. It is in this context that the present study has set the objective of analyzing the techniques of conservation of agricultural land used in the rural commune of Sanankoroba in order to contribute to their sustainable management. The methodological approach adopted focused on the documentary review and the analysis of quantitative and qualitative survey data. The data collected in February 2021 was subjected to descriptive statistical analysis using SPSS 20.00 and Excel 2016 software and discourse content analysis. The results of the study show an overexploitation of the land, which seriously threatens the soil resources of the commune. The agricultural land conservation techniques used by the peasants of the commune are erosion control measures (different kinds of stone barriers, grassy strips, earthen bunds), fallowing, the use of mineral fertilizers and organic manure. It appears that the sustainable management of agricultural land in the rural commune of Sanankororba requires the popularization of environmentally friendly agricultural techniques and inputs and better support for farmers.Résumé&nbsp; La commune rurale de Sanankororba située dans le cercle de Kati au Mali, est caractérisée par une très grande diversité d’écosystèmes naturels, qui hébergent des ressources telles que les sols, la végétation, les eaux. Ces éléments constituent la principale richesse de la commune dont les activités agricoles occupent la majeure partie de la population et lui fournissent l’essentiel de ses moyens d’existence. Cependant, depuis quelques décennies, on assiste à une dégradation continue des terres agricoles en raison surtout de la pression démographique, des partiques agricoles néfastes et des aléas climatiques. C’est dans ce contexte que la présente étude s’est fixée comme objectif d’analyser les techniques de conservation des terres agricoles utilisées dans la commune rurale de Sanankoroba en vue de contribuer à leur gestion durable. L’approche méthodologique adoptée a porté sur la revue documentaire et l’analyse des données d’enquêtes quantitatives et qualitatives. Les données collectées en février 2021 ont fait l’objet d’une analyse statistique descriptive à l’aide des logiciels SPSS 20.00 et Excel 2016 et d’une analyse de contenu des discours. Les résultats de l’étude montrent une surexploitation des terres, qui menace sérieusement les ressources pédologiques de la commune. Les techniques de conservation des terres agricoles adoptées par les paysans de la commune portent sur les mesures de lutte antiérosive (cordons pierreux, barrières en cailloux, bandes enherbées, diguettes en terre), la jachère, l’utilisation des engrais minéraux et de la fumure organique. Il resort que la gestion durable des terres agricoles dans la commune rurale de Sanankororba nécessite la vulgarisation des techniques et intrants agricoles respectueux de l’environnement et un meilleur accompagnement des exploitants

Gestion durable des terres agricoles dans la commune rurale de Sanankoroba, cercle de Kati

Summary The rural commune of Sanankororba located in the circle of Kati in Mali, is characterized by a very great diversity of natural ecosystems, which host resources such as soil, vegetation, water. These elements constitute the main wealth of the commune whose agricultural activities occupy the majority of the population and provide them with the essential of their means of existence. However, for several decades, there has been a continuous degradation of agricultural land mainly due to demographic pressure, harmful agricultural practices and climatic hazards. It is in this context that the present study has set the objective of analyzing the techniques of conservation of agricultural land used in the rural commune of Sanankoroba in order to contribute to their sustainable management. The methodological approach adopted focused on the documentary review and the analysis of quantitative and qualitative survey data. The data collected in February 2021 was subjected to descriptive statistical analysis using SPSS 20.00 and Excel 2016 software and discourse content analysis. The results of the study show an overexploitation of the land, which seriously threatens the soil resources of the commune. The agricultural land conservation techniques used by the peasants of the commune are erosion control measures (different kinds of stone barriers, grassy strips, earthen bunds), fallowing, the use of mineral fertilizers and organic manure. It appears that the sustainable management of agricultural land in the rural commune of Sanankororba requires the popularization of environmentally friendly agricultural techniques and inputs and better support for farmers.Résumé&nbsp; La commune rurale de Sanankororba située dans le cercle de Kati au Mali, est caractérisée par une très grande diversité d’écosystèmes naturels, qui hébergent des ressources telles que les sols, la végétation, les eaux. Ces éléments constituent la principale richesse de la commune dont les activités agricoles occupent la majeure partie de la population et lui fournissent l’essentiel de ses moyens d’existence. Cependant, depuis quelques décennies, on assiste à une dégradation continue des terres agricoles en raison surtout de la pression démographique, des partiques agricoles néfastes et des aléas climatiques. C’est dans ce contexte que la présente étude s’est fixée comme objectif d’analyser les techniques de conservation des terres agricoles utilisées dans la commune rurale de Sanankoroba en vue de contribuer à leur gestion durable. L’approche méthodologique adoptée a porté sur la revue documentaire et l’analyse des données d’enquêtes quantitatives et qualitatives. Les données collectées en février 2021 ont fait l’objet d’une analyse statistique descriptive à l’aide des logiciels SPSS 20.00 et Excel 2016 et d’une analyse de contenu des discours. Les résultats de l’étude montrent une surexploitation des terres, qui menace sérieusement les ressources pédologiques de la commune. Les techniques de conservation des terres agricoles adoptées par les paysans de la commune portent sur les mesures de lutte antiérosive (cordons pierreux, barrières en cailloux, bandes enherbées, diguettes en terre), la jachère, l’utilisation des engrais minéraux et de la fumure organique. Il resort que la gestion durable des terres agricoles dans la commune rurale de Sanankororba nécessite la vulgarisation des techniques et intrants agricoles respectueux de l’environnement et un meilleur accompagnement des exploitants

Geothermal parameter assessment in the Southwestern Sokoto Basin, Nigeria, using spectral analysis (centroid method)

This study utilized spectral analysis (centroid method) to assess geothermal parameters in the southwestern part of the Sokoto Basin, Nigeria. The high-resolution airborne data comprised forty-nine (49) overlapping blocks, and each block was divided into 55x55 km to evaluate essential parameters such as depth to the top boundary (Zt ), centroid depth (Zo), and magnetic source bottom (Zb = 2Zo-Zt ). The analysis revealed variable Curie points depths (CPD), ranging from 3.89 km to 26.56 km. The lowest CPD is primarily associated with basement rocks within anomalies A, B, C, D, E, F, G, H, and I, with an average CPD of 9.16 km. Furthermore, the thermal gradients ranged from 21.84 ◦C/km to 149.10 ◦C/km, with an average thermal gradient of 73.30 ◦C/km. The heat flow exhibited variations between 54.81 mW/m² and 374.24 mW/m², with average heat flow of 180.4 mW/m², indicating significant geothermal potential zones. The high thermal gradients and heat flow regions were identified, around anomalies A, B, and C. Additionally, temperature gradients identified at shallow depths ranged from 110 ◦C/km to 150 ◦C/km. The results reveal the presence of high-temperature points and anomalous geothermal potentials, particularly within anomalies A, B, and C, thus requiring further for sustainable geothermal energy generation in the study area

Intermittent preventive treatment of malaria provides substantial protection against malaria in children already protected by an insecticide-treated bednet in Burkina Faso: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Intermittent preventive treatment of malaria in children (IPTc) is a promising new approach to the control of malaria in areas of seasonal malaria transmission but it is not known if IPTc adds to the protection provided by an insecticide-treated net (ITN). METHODS AND FINDINGS: An individually randomised, double-blind, placebo-controlled trial of seasonal IPTc was conducted in Burkina Faso in children aged 3 to 59 months who were provided with a long-lasting insecticide-treated bednet (LLIN). Three rounds of treatment with sulphadoxine pyrimethamine plus amodiaquine or placebos were given at monthly intervals during the malaria transmission season. Passive surveillance for malaria episodes was established, a cross-sectional survey was conducted at the end of the malaria transmission season, and use of ITNs was monitored during the intervention period. Incidence rates of malaria were compared using a Cox regression model and generalized linear models were fitted to examine the effect of IPTc on the prevalence of malaria infection, anaemia, and on anthropometric indicators. 3,052 children were screened and 3,014 were enrolled in the trial; 1,505 in the control arm and 1,509 in the intervention arm. Similar proportions of children in the two treatment arms were reported to sleep under an LLIN during the intervention period (93%). The incidence of malaria, defined as fever or history of fever with parasitaemia ≥ 5,000/µl, was 2.88 (95% confidence interval [CI] 2.70-3.06) per child during the intervention period in the control arm versus 0.87 (95% CI 0.78-0.97) in the intervention arm, a protective efficacy (PE) of 70% (95% CI 66%-74%) (p<0.001). There was a 69% (95% CI 6%-90%) reduction in incidence of severe malaria (p = 0.04) and a 46% (95% CI 7%-69%) (p = 0.03) reduction in the incidence of all-cause hospital admissions. IPTc reduced the prevalence of malaria infection at the end of the malaria transmission season by 73% (95% CI 68%-77%) (p<0.001) and that of moderately severe anaemia by 56% (95% CI 36%-70%) (p<0.001). IPTc reduced the risks of wasting (risk ratio [RR] = 0.79; 95% CI 0.65-1.00) (p = 0.05) and of being underweight (RR = 0.84; 95% CI 0.72-0.99) (p = 0.03). Children who received IPTc were 2.8 (95% CI 2.3-3.5) (p<0.001) times more likely to vomit than children who received placebo but no drug-related serious adverse event was recorded. CONCLUSIONS: IPT of malaria provides substantial protection against malaria in children who sleep under an ITN. There is now strong evidence to support the integration of IPTc into malaria control strategies in areas of seasonal malaria transmission. TRIAL REGISTRATION: ClinicalTrials.govNCT00738946. Please see later in the article for the Editors' Summary