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Background Influenza is a serious vaccine-preventable disease with high incidence, hospitalization, and mortality in high-risk groups. The epidemiology, seasonality, and risk factors for influenza are well defined in most of the temperate countries, but estimating influenza burden in the World Health Organization (WHO) Region for the Eastern Mediterranean is scarce. In Oman, despite the advancements in influenza surveillance, the clinical burden and seasonality of influenza remain not fully understood. Objectives To estimate the incidence of influenza-associated hospitalizations and in-hospital death in Oman. Patients and methods Influenza-associated hospitalizations and in-hospital deaths were estimated using hospital discharge records based on ICD-10 codes (J09-J18), results of virological analysis and population census for the period between 2012 and 2015. Results During 2012 and 2015, we identified a total of 19 405 influenza-associated hospitalization and 847 deaths. Influenza positivity percentage ranged from 6.4% in 2013 to 20.6% in 2015. Influenza-associated hospitalization incidence rate was 7.3 (95% CI: 6.4-8.1) per 100 000 in 2013 and 27.5 (95% CI: 25.9-29.1) per 100 000 in 2015 with an overall rate of 20.6 (95% CI: 19.9-21.3) per 100 000. The highest incidence of influenza-associated death was among those aged ≥65 years and ranged between 39.5 (95% CI: 27.3-51.8) per 100 000 in 2014 and 11.3 (95% CI: 7.5-15.1) in 2015. Conclusions Influenza causes a substantial number of hospitalizations and deaths in Oman. Hospitalization rates were highest among children, and adults ≥65 years showed the highest death rate. The potential value of using seasonal influenza vaccine in these groups should be considered.

(IF 1.06; Q3); International audience; Hydrocarbon contamination, which can alter the physiochemical and biological properties of the subsurface, can be monitored by using geochemical analyses and integrated geophysical techniques. Electrical resistivity tomography, induced polarization, ground-penetrating radar, and self-potential methods were used in this work to characterise the hydrocarbon contamination and investigate the geoelectrical properties of a site impacted by an aged hydrocarbon plume. Throughout the investigation, geoelectrical measurements supported the conductive plume model and consistently recorded low-resistivity anomalies and high-chargeability values in the contaminated aquifer. Furthermore, the low-resistivity anomalies were found to be coincident with regions of ground-penetrating radar attenuated reflections and significant negative self-potential anomalies associated with oxidation– reduction processes. These findings were supported by the geochemical measurements, which revealed depleted concentrations of terminal electron acceptors (TEAs) and elevated amounts of ions and total dissolved solids, which could be attributed to bacterial biodegradation of hydrocarbons. The study showed that biological alterations of hydrocarbon-induced subtle changes in the pore water biogeochemistry, which consequently modified the geophysical properties of the contaminated sediments. Based on these observations, the extent of groundwater contamination was delineated according to the geophysical contrast between the contaminated and clean zones. The combination of different geophysical methods constrained by geochemical point measurements provided insight on the different processes that might have modified the soil and groundwater biogeochemical properties.

The French critical zone initiative, called OZCAR (Observatoires de la Zone Critique–Application et Recherche or Critical Zone Observatories–Application and Research) is a National Research Infrastructure (RI). OZCAR-RI is a network of instrumented sites, bringing together 21 pre-existing research observatories monitoring different compartments of the zone situated between “the rock and the sky,” the Earth’s skin or critical zone (CZ), over the long term. These observatories are regionally based and have specific initial scientific questions, monitoring strategies, databases, and modeling activities. The diversity of OZCAR-RI observatories and sites is well representative of the heterogeneity of the CZ and of the scientific communities studying it. Despite this diversity, all OZCAR-RI sites share a main overarching mandate, which is to monitor, understand, and predict (“earthcast”) the fluxes of water and matter of the Earth’s near surface and how they will change in response to the “new climatic regime.” The vision for OZCAR strategic development aims at designing an open infrastructure, building a national CZ community able to share a systemic representation of the CZ , and educating a new generation of scientists more apt to tackle the wicked problem of the Anthropocene. OZCAR articulates around: (i) a set of common scientific questions and cross-cutting scientific activities using the wealth of OZCAR-RI observatories, (ii) an ambitious instrumental development program, and (iii) a better interaction between data and models to integrate the different time and spatial scales. Internationally, OZCAR-RI aims at strengthening the CZ community by providing a model of organization for pre-existing observatories and by offering CZ instrumented sites. OZCAR is one of two French mirrors of the European Strategy Forum on Research Infrastructure (eLTER-ESFRI) project.

International audience; Large‐scale inversion methods have been recently developed and permitted now to considerably reduce the computation time and memory needed for inversions of models with a large amount of parameters and data. In this work, we have applied a deterministic geostatistical inversion algorithm to a hydraulic tomography investigation conducted in an experimental field site situated within an alluvial aquifer in Southern France. This application aims to achieve a 2‐D large‐scale modeling of the spatial transmissivity distribution of the site. The inversion algorithm uses a quasi‐Newton iterative process based on a Bayesian approach. We compared the results obtained by using three different methodologies for sensitivity analysis: an adjoint‐state method, a finite‐difference method, and a principal component geostatistical approach (PCGA). The PCGA is a large‐scale adapted method which was developed for inversions with a large number of parameters by using an approximation of the covariance matrix, and by avoiding the calculation of the full Jacobian sensitivity matrix. We reconstructed high‐resolution transmissivity fields (composed of up to 25,600 cells) which generated good correlations between the measured and computed hydraulic heads. In particular, we show that, by combining the PCGA inversion method and the hydraulic tomography method, we are able to substantially reduce the computation time of the inversions, while still producing high‐quality inversion results as those obtained from the other sensitivity analysis methodologies.

The coastal shelf of the Gulf of Oman experiences periodic upwelling events during the summer months that are driven by the southwest monsoon. It is unclear what role these events play in the spatial and temporal distribution of the region’s fish assemblage. We carried out trials on two different video techniques to characterize the habitat and fish assemblage along the continental shelf margin near Muscat, Oman. Exploratory surveys with a drift stereo-video revealed three main habitat types: Sand, Reef and Megabenthos. Three areas were chosen for additional sampling using stereo-BRUVS (‘baited’ remote underwater-video systems). On two separate occasions (November 2005 and March 2006) replicate stereo-BRUVS were deployed in each area stratified by the main habitat types. For each teleost and elasmobranch species encountered on the video, an estimate of total body length and the relative abundance (MaxNi) was made. The stereo-BRUVS recorded a wide range of demersal and pelagic teleosts including species of conservation interest such as sharks, rays and groupers. The drift stereo-video recorded significantly fewer species than the stereo-BRUVS (N = 15 versus N = 43). Species diversity from the stereo-BRUVS increased by 96% in March 2006 (N = 41) compared to November 2005 (N = 23), a pattern consistent at all three areas. The structure of the overall fish assemblage (using canonical analysis of principal coordinates analysis) was highly variable both in time and space. There was ample evidence of strong habitat associations, particularly with depth and seasonal shifts in abundance and diversity. We argue the upward migration of oxygen-depleted water into the shallow depths during the late monsoon displaces the demersal fish community along this coast.