127 research outputs found

    0541: Management of heart failure: experiences in African patients

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    AimTo determine clinical characteristics and mode of treatment of patients with heart failure in Yaounde military hospital (YMH).MethodsData of patients with heart failure (HF) followed on a period of 6 months in YMH were used to determine clinical characteristics and mode of treatment.ResultsA total of 72 patients were consecutively studied comprising 45 men (62.5%) and 27 women (37.5%) aged 62.8±16.5 and 61.1±19.4 years, respectively. All the patients presented with NYHA functional class III or IV. Alcohol was the most common etiological factor of HF (66.7%) hypertension was the most common risk factor for HF (37.5%) while only 16.7% of the patients were smokers. Global heart failure was the common presentation (60.9%). Left bundle branch was present in 47% of electrocardiograms while 8.7% of the patients were in atrial fibrillation. Dilated cardiomyopathy was the common lesion (80%). Most patients presented with severe left ventricular (LV) systolic dysfunction (66.6%). Male subjects had worse LV systolic dys-function compare to women without significant difference (56.3% vs 43.8% p=0.8). Diabete was not associated with severe LV dysfunction (78.9% on non diabetic vs 6.3% of diabetic patients). Current recommended pharmacology therapies were used in most of the cases. Diuretics were used in 100% while ACE inhibitors were in 91.3% of cases. 52.4% of patients had beta blockers.ConclusionMost heart failure patients in Cameroon present in the sixth decade with severe heart failure. All the recommended therapies are not available in our country

    Les arbres dans les systèmes agraires en zone sahélienne du Niger: mode de gestion, atouts et contraintes

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    Trees in the Agrarian Systems of the Sahelian Zone of Niger: Management Practices, Benefits and Constraints. In the Sahelian regions, tree is an integrated part of the farming systems. The present study concerns the tree management practices, their benefits and constraints. A survey was conducted in 7 village sites of the southwestern part of Niger according to a southnorth aridity gradient in order to understand how rural people manage trees in their farms. The objective was to analyse the systems, tree management practices, benefits and constraints. The results show that rural people of the arid zone manage and preserve trees in their farms better than the population of the semi-arid zone. Land fallow is practiced in 87.91% of the plots for a mean period of 4.4 years. Land clearing was also practiced by 98.9% of the questionned farmers and the mean number of trees that were not cut varied from 8 in the semi-arid zone to 20 in the arid zone. Trees in the farms were used to delimitate farms boundaries, improve soil fertility, to prepare traditional medecine and as energy source and timber. The sociocultural habits of the people are the main constraint to an adequate management of the tree resources. To change the current situation, sensitization and extension efforts of the new developped tree management techniques have to be carried out especially in the semi-arid zone

    Spatial analysis of hydrological and phytoplanktonic data of the Bay of Tunis. Multivariate cartography

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    A method of cartography originally used in geology was adapted to generate regionalization and to obtain 2-D maps of multivariate marine data. The ecological purpose of the method is to divide the studied area through homogeneous regions presenting common multivariate characteristics. Firstly, transformation was applied to the original matrix of hydrological parameters in order to satisfy the condition of multinormality. Then, associative analysis was used in order to produce an easy to interpret partition of sites. The level of heterogeneity between each station and the properties of each group was assessed by measuring the Bayesian probabilities. These conditional probabilities measure the chance that each site has of belonging to a predefined group of sites. Based on the geographical positions of the stations, the probability values for each group of stations were mapped using kriging interpolation algorithm. The obtained maps of iso-probabilities for the different groups of stations were used to define homogenous zones on a single map. Including the phytoplanktonic dataset afterwards, the indicator species were identified for each zone.This multivariate analysis was applied to a hydrological and phytoplanktonic dataset of the Bay of Tunis. Measures at surface were made at 17 stations, sampled monthly over 2 years. The results illustrated a partition of the bay considering four groups, two coastal and two central groups of stations. The importance of the inshore influence was demonstrated in the setting up of such a regionalization through the inflow of alluvium and other products of coastal activities. The significant presence of the toxic phytoplanktonic community in the bay suggests the need to institute a monitoring program

    Trust in Crowds: probabilistic behaviour in anonymity protocols

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    The existing analysis of the Crowds anonymity protocol assumes that a participating member is either ‘honest’ or ‘corrupted’. This paper generalises this analysis so that each member is assumed to maliciously disclose the identity of other nodes with a probability determined by her vulnerability to corruption. Within this model, the trust in a principal is defined to be the probability that she behaves honestly. We investigate the effect of such a probabilistic behaviour on the anonymity of the principals participating in the protocol, and formulate the necessary conditions to achieve ‘probable innocence’. Using these conditions, we propose a generalised Crowds-Trust protocol which uses trust information to achieves ‘probable innocence’ for principals exhibiting probabilistic behaviour

    Born small, die young: Intrinsic, size-selective mortality in marine larval fish

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    Mortality during the early stages is a major cause of the natural variations in the size and recruitment strength of marine fish populations. In this study, the relation between the size-at-hatch and early survival was assessed using laboratory experiments and on field-caught larvae of the European sardine (Sardina pilchardus). Larval size-at-hatch was not related to the egg size but was significantly, positively related to the diameter of the otolith-at-hatch. Otolith diameter-at-hatch was also significantly correlated with survival-at-age in fed and unfed larvae in the laboratory. For sardine larvae collected in the Bay of Biscay during the spring of 2008, otolith radius-at-hatch was also significantly related to viability. Larval mortality has frequently been related to adverse environmental conditions and intrinsic factors affecting feeding ability and vulnerability to predators. Our study offers evidence indicating that a significant portion of fish mortality occurs during the endogenous (yolk) and mixed (yolk /prey) feeding period in the absence of predators, revealing that marine fish with high fecundity, such as small pelagics, can spawn a relatively large amount of eggs resulting in small larvae with no chances to survive. Our findings help to better understand the mass mortalities occurring at early stages of marine fish.info:eu-repo/semantics/publishedVersio

    Novel composite materials of modified roasted date pits using ferrocyanides for the recovery of lithium ions from seawater reverse osmosis brine

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    In this paper, novel composite materials from modified roasted date pits using ferrocyanides were developed and investigated for the recovery of lithium ions (Li+) from seawater reverse osmosis (RO) brine. Two composite materials were prepared from roasted date pits (RDP) as supporting material, namely potassium copper hexacyanoferrate-date pits composite (RDP-FC-Cu), and potassium nickel hexacyanoferrate-date pits composite (RDP-FC-Ni). The physiochemical characterization of the RO brine revealed that it contained a variety of metals and salts such as strontium, zinc, lithium, and sodium chlorides. RDP-FC-Cu and RDP-FC-Ni exhibited enhanced chemical and physical characteristics than RDP. The optimum pH, which attained the highest adsorption removal (%) for all adsorbents, was at pH 6. In addition, the highest adsorption capacities for the adsorbents were observed at the initial lithium concentration of 100 mg/L. The BET surface area analysis confirmed the increase in the total surface area of the prepared composites from 2.518 m2/g for RDP to 4.758 m2/g for RDP-FC-Cu and 5.262 m2/g for RDP-FC-Ni. A strong sharp infrared peak appeared for the RDP-FC-Cu and RDP-FC-Ni at 2078 cm−1. This peak corresponds to the C≡N bond, which indicates the presence of potassium hexacyanoferrate, K4[Fe(CN)6]. The adsorption removal of lithium at a variety of pH ranges was the highest for RDP-FC-Cu followed by RDP-FC-Ni and RDP. The continuous increase in the adsorption capacity for lithium with increasing initial lithium concentrations was also observed. This could be mainly attributed to enhance and increased lithium mass transfer onto the available adsorption active sites on the adsorbents’ surface. The differences in the adsorption in terms of percent adsorption removal were clear and significant between the three adsorbents (P value < 0.05). All adsorbents in the study showed a high lithium desorption percentage as high as 99%. Both composites achieved full recoveries of lithium from the RO brine sample despite the presence of various other competing ions.This work was made possible by Qatar University collaborative internal grant # [QUCG-CAS-20/21-2]. The findings achieved herein are solely the responsibility of the author[s]
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