Prospección minera de la mineralización de óxidos de Fe-Mn-Pb en Jbel Skindis (Alto Atlas Oriental, Marruecos) basada en teledetección y SIG

In recent years, remote sensing has had a prominent place in mineral exploration programs given its potential to identify alteration minerals, such as clay and hydroxyl minerals. Those minerals represent significant guides to mineral deposits considering their potential to host valuable concentrations of base metal elements. This work focuses on Fe-Mn-Pb mineral deposits within the Jbel Skindis area as a case study to illustrate the application of remote sensing images and GIS systems to highlight prospective zones and to extract information on ore-controlling factors using image enhancement and integration methods. Field observations and XRD data showed that the main remotely sensed alteration anomalies are characterized by oxides and hydroxides. Based on those indicative minerals, a mapping using Aster L1T and Landsat 8 OLI data was done: the 5/4 ratio highlighted gossans zones and the RGB combination (4/6, 2/1, 3/2) accentuates the hydrothermally altered areas. The lineament map extracted from Sentinel 2A and Landsat imagery allowed the reconstitution of the megafracture network that affected the region. The multi-criteria analysis of these satellite-derived data along with available geological data outcomes to delineate prospective zones in the study area, were found to be in highly fractured areas developing gossans and Fe rich alteration. Verified via field survey, this approach was successfully applied to the Jbel Skindis area to rapidly delineate oxidized ore outcrops. This provides a remote sensing model for future prospecting efforts for similar mineral deposits both in the Eastern High-Atlas province and in other similar areas.En los últimos años, la teledetección ha ocupado un lugar destacado en los programas de exploración minera dada su utilidad para identificar minerales de alteración, como la arcilla y los hidróxidos. Estos minerales son guías significativas para encontrar depósitos minerales que albergan concentraciones valiosas de metales base. Este trabajo se centra en las mineralizaciones de Fe-Mn-Pb dentro del área de Jbel Skindis consideradas como un zona de estudio para ilustrar la aplicación de imágenes de teledetección y de un sistema SIG para delinear zonas de interés para la exploración minera y extraer información sobre los factores que controlan las concentraciones de metales utilizando tratamiento de datos satélites e integración de imágenes. De acuerdo con las observaciones de campo y los datos DRX las principales anomalías de alteración deducidas del tratamiento de datos satélite se caracterizan por óxidos e hidróxidos. En base a estos minerales, se realizó un mapeo utilizando los datos de Aster L1T y Landsat 8 OLI: la relación 5/4 resalta las zonas de Gossans mientras la combinación RGB (4/6, 2/1, 3/2) señala las áreas alteradas. El mapa de lineamientos extraído de las imágenes de Sentinel 2A y Landsat permitió reconstituir la red de megafracturas que afectó a la región. El acoplamiento entre un análisis multi-criterio de los datos derivados de satélites y los datos geológicos disponibles, permitió delinear zonas de interés para la exploración minera en el área de estudio. Estas zonas corresponden a áreas altamente fracturadas en las cuales se desarrollan gossans y alteración rica en Fe. Este enfoque junto con un control a través de un estudio de campo, se aplicó con éxito en el área de Jbel Skindis para delinear rápidamente los afloramientos de mineralizaciones oxidadas. Esto proporciona un modelo de teledetección para futuros esfuerzos de prospección de depósitos minerales similares tanto en la provincia oriental del Alto Atlas como en otras áreas similares

Medication Sector in Qatar: Hand in Hand Facing the Blockade

Conference agend

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie