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We study by means of the 2D Blume–Emery–Griffiths (BEG) spin-1 model, spin-crossover (SCO) and prussian blue analogs (PBAs) solids. In this model, the spin states, which can be high-spin (HS) or low-spin (LS), interact magnetically and elastically with their nearest neighbors. To account for the volume change, accompanying the spin transition phenomenon, all interactions through the lattice are assumed as temperature-dependent. In addition, the system is subject to a variable magnetic field lifting the degeneracy in the HS state. A stochastic cooperative dynamics of this BEG-like Hamiltonian, describing the equilibrium and nonequilibrium properties of ferromagnetic spin-crossover solids, is derived from the Glauber approach, with appropriate Arrhenius microscopic transition rates. The model generates under the magnetic field, sigmoidal relaxation and a hysteresis phenomenon of the HS fraction, as well as multistep behavior of the magnetization. These behaviors open the way to new route of multi-stable systems, desired in multi-byte electronics. [ABSTRACT FROM AUTHOR]

In the central western Senegal, great progress has been made against malaria following the successful implementation of effective malaria control interventions, including Indoor Residual Spraying (IRS) and Seasonal Malaria Chemoprevention (SMC). However, residual transmissions are still occurring in several hotspots involving some secondary vector species, such as An. melas. This study was undertaken in central and western costal area of Senegal, to provide the first data on the insecticide susceptibility of local An. melas population using WHO test kits, the allelic frequencies of the Kdr and Ace-1R mutations using qPCR and also re-evaluate the palp biometry technique as a proxy to discriminate An. melas from other freshwater species within the Gambiae complex. Insecticide susceptibility test revealed a susceptibility of An. melas to Pirimiphos-methyl, and Bendiocarb, the two main non-pyrethroid insecticides recommended by the WHOPES for use in public health. The molecular characterization of the Kdr and Ace-1 target site mutations revealed the absence of both mutations. The biometric palps technique has been a valid method for species diagnose between An. melas and its freshwater sibling. Indeed, while the former species collected exclusively from salty breeding sites (with a level of salinity above 21 g/l), consistently displayed a palpal index ≥0.81; the latter, sampled for breeding site of low salinity level (up to 3.6 g/l) and subsequently mainly identified as An. arabiensis and in a lesser extend as An. gambiae, presented a palpal index less than 0.81. This study has re-evaluated and validated the palps biometric technique as a morphological tool for the identification of An. melas, which population still susceptible to main insecticide used in public health and revealed the absence of KDR and Ace-1 mutations. The data provided here can help the Senegalese NMCP to better target and efficiently control An. melas populations in malaria hotspot, where they contribute to maintain residual transmission hampering the malaria elimination goal. [ABSTRACT FROM AUTHOR]

To address the epidemic of hypertension in blacks born and living in sub-Saharan Africa, we compared in a randomised clinical trial (NCT01030458) single-pill combinations of old and new antihypertensive drugs in patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mm Hg). After 4 weeks off treatment, 183 of 294 screened patients were assigned to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (n=89; R) or amlodipine/valsartan 5/160 mg (n=94; E) and followed up for 6 months. To control blood pressure (<140/<90 mm Hg), bisoprolol and amlodipine could be doubled (10 mg per day) and α-methyldopa (0.5-2 g per day) added. Sitting blood pressure fell by 19.5/12.0 mm Hg in R patients and by 24.8/13.2 mm Hg in E patients and heart rate decreased by 9.7 beats per minute in R patients with no change in E patients (-0.2 beats per minute). The between-group differences (R minus E) were 5.2 mm Hg (P<0.0001) systolic, 1.3 mm Hg (P=0.12) diastolic, and 9.6 beats per minute (P<0.0001). In 57 R and 67 E patients with data available at all visits, these estimates were 5.5 mm Hg (P<0.0001) systolic, 1.8 mm Hg (P=0.07) diastolic and 9.8 beats per minute (P<0.0001). In R compared with E patients, 45 vs 37% (P=0.13) proceeded to the higher dose of randomised treatment and 33 vs 9% (P<0.0001) had α-methyldopa added. There were no between-group differences in symptoms except for ankle oedema in E patients (P=0.012). In conclusion, new compared with old drugs lowered systolic blood pressure more and therefore controlled hypertension better in native African black patients. [ABSTRACT FROM AUTHOR]

The effects of 18 years continuous cropping of irrigated rice on soil and yields were studied in two long-term fertility experiments (LTFE) at Ndiaye and Fanaye in the Senegal River Valley (West Africa). Rice was planted twice in a year during the hot dry season (HDS) and wet season (WS) with different fertilizer treatments. Soil organic carbon (SOC) under fallow varied from 7.1 g kg−1 at Fanaye to 11.0 g kg−1 at Ndiaye. Rice cropping maintained and increased SOC at Ndiaye and Fanaye, respectively and fertilizer treatments did not affect SOC. Soil available P and exchangeable K were maintained or increased with long-term application of NPK fertilizers. Without any fertilizer, yields decreased by 60 kg ha−1 (1.5%) and 115 kg ha−1 (3%) per year at Fanaye and Ndiaye, respectively. The highest annual yield decreases of 268 kg ha−1 (3.6%) and 277 kg ha−1 (4.1%) were observed at Fanaye and Ndiaye, respectively when only N fertilizer was applied. Rice yields were only maintained with NPK fertilizers supplying at least 60 kg N, 26 kg P and 50 kg K ha−1. It was concluded that the double cropping of irrigated rice does not decrease SOC and the application of the recommended doses of NPK fertilizer maintained rice yields for 18 years. [ABSTRACT FROM AUTHOR]

The paper deals with the problem of locating new facilities in presence of attracting and repulsive demand points in a continuous location space. When an arbitrary norm is used to measure distances and with closed convex constraints, we develop necessary conditions of efficiency. In the unconstrained case and if the norm derives from a scalar product, we completely characterize strict and weak efficiency and prove that the efficient set coincides with the strictly efficient set and/or coincides with the weakly efficient set. When the convex hulls of the attracting and repulsive demand points do not meet, we show that the three sets coincide with a closed convex set for which we give a complete geometrical description. We establish that the convex hulls of the attracting and repulsive demand points overlap iff the weakly efficient set is the whole space and a similar result holds for the efficient set when we replace the convex hulls by their relative interiors. We also provide a procedure which computes, in the plane and with a finite number of demand points, the efficient sets in polynomial time. Concerning constrained efficiency, we show that the process of projecting unconstrained weakly efficient points on the feasible set provides constrained weakly efficient points. [ABSTRACT FROM AUTHOR]

The effects of soil solarization combined or not with millet residues or paunch contents amendments, on the survival of Macrophomina phaseolina (Tassi) Goid. and development of charcoal rot of cowpea ( Vigna unguiculata), were assessed in a naturally infested soil. Solarization increased the soil temperature to 50°C for at least 4 h per day during June, leading to a significant reduction (44%) in soil inoculum of M. phaseolina. Paunch contents or millet residues amendment (3 t ha−1) caused 16% or 35% reduction of initial inoculum density, respectively. The combination of paunch contents or millet residues amendments followed by solarization, resulted in the strongest effects on inoculum density, with reductions of 46% or 66%, respectively. The reduction in disease severity, as expressed by the area under the disease progress curve, was 78% or 96% for the combination of millet residues or paunch contents amendments and solarization, respectively. The stronger effect of the treatments on disease severity than on inoculum density may be explained by a weakening effect caused by the treatments on the remaining inoculum. Our results suggest that in the Sahelian zone the combination of solarization and organic amendment can be a credible alternative to pesticides for managing charcoal rot disease and improving cowpea yield in fields with heavy infestations with M. phaseolina. [ABSTRACT FROM AUTHOR]

The arch of the great saphenous vein presents numerous tributaries. Misappreciation of their anatomical variations might cause recurrence after surgical treatment of varices. We dissected 54 inguino-femoral regions of fresh, black African corpses. Our purpose was to study the anatomical variations in the vein confluents of the arch of the great saphenous vein; its positions in relation to the external pudendal artery; establish palpable anatomical markers for its surgical approach. The conventional type in a ‘vein star’ shape was not the most frequent. Upper or abdominal common vein produced through the merging of superficial veins of the anterior abdominal wall and genital or internal common vein were more frequent. An anterior saphenous vein was found in 23 cases. The external pudendal artery crossed beneath the arch of the great saphenous vein cross in 56% of cases and previously in 44% of cases. On average, the top of the arch of the great saphenous vein was projected out 10.88 cm from the ventral and cranial iliac spine, 3.83 cm from the pubic tubercle and 4.19 cm from the inguinal ligament. In view of our results, variations are real. Knowing and taking them into account are essential to prevent recurrences after surgical treatment of varices of the pelvic limb. [ABSTRACT FROM AUTHOR]

Objectives: Study of the hemodynamic profile and oxygenation variables in severe malaria to determine whether they are identical to those observed in severe bacterial infections. Design and setting: Prospective study in an intensive care unit of a West African hospital. Patients and participants: Two groups of adult patients hospitalized for severe malaria according to WHO criteria, a control group (n=13) with systemic vascular resistance of 800 dyne s–1 cm–5 or higher and a hyperkinetic group (n=16) with a level lower than 800 dyne s–1 cm–5. Twenty-nine patients participated in this study (19 semi-immune, 10 nonimmune). Interventions: Before hemodynamic study a loading dose of quinine formiate was administered: 20 mg/kg intravenously for 4 h. Artificial ventilation was used in the case of persistent hypoxemia. Measurements and results: The hemodynamic study with Swan-Ganz catheter was performed after filling with 1000 ml lactated Ringer's solution. From a clinical and a biological standpoint there was no difference between the two groups except for creatine phosphokinase, which was significantly higher in the hyperkinetic group: 2404±3654 vs. 1898±1828 IU/l. Hemodynamic and oxygenation variables showed a significant difference in cardiac index (6.1±1.2 vs. 3.9±1.2 l min–1 m–2), systemic vascular resistance (536±143 vs. 1098±170 dyne s–1 cm–5), oxygen delivery (645±163 vs. 482±186 ml min–1 m–2), and oxygen extraction (23±9% vs. 34±14%). Oxygen extraction was negatively correlated with oxygen delivery in the control group but not in the hyperkinetic group. Eight of 10 nonimmune patients (80%) were in the hyperkinetic group versus 8 of 19 semi-immune patients (42%; p<0.05). Nine patients in the hyperkinetic group (69%) and seven of the control group (46%) died (NS). Conclusions: In contrast to severe bacterial infections, severe malaria does not always induce hyperkinetic-type hemodynamic changes. Such changes are observed mostly in nonimmune subjects. [ABSTRACT FROM AUTHOR]

Objective: Acute chloroquine intoxication is responsible for a membrane-stabilising effect which results in electrocardiographic (ECG) and hemodynamic disturbances. Diazepam is used in acute chloroquine intoxication on the basis of clinical and experimental observations, but its utility alone, in man, remains unproven. The goal of this study was to verify whether diazepam alone has an effect on the membrane-stabilising effect observed in moderately severe chloroquine intoxications.Design: Prospective, multi-center, double-blind, placebo-controlled study.Setting: Prehospital mobile intensive care units (Paris) and hospital intensive care units (paris and Dakar).Patients and Participants: Adults with moderately severe intoxication defined as: a suspected ingested dose of 2 or more but less than 4 g, systolic blood pressure (SBP) higher than 80 mmHg, QRS duration less than 0.12 s and the absence of dysrhythmia at inclusion.Interventions: Patients received either a loading dose of 0.5 mg/kg diazepam followed by an infusion of 1 mg/kg over 24 h or an equivalent volume of placebo.Measurements and Results: Outcome was measured by serial assessments of SBP, ECG (QRS and QT segments) and clinical deterioration. There were no significant differences observed in the initial or serial ECG or SBP measurements. There were no deaths and no patient had to be removed from the study due to clinical deterioration.Conclusions: Diazepam, at the dose studied, does not appear to reverse the chloroquine-induced membrane-stabilising effect in acute moderately severe chloroquine intoxication. Supportive intensive care of these intoxications appears to be all that is necessary. [ABSTRACT FROM AUTHOR]

A study was conducted to evaluate repeated intrathecal injections of baclofen, without artificial ventilation, in the treatment of severe tetanus. Ten patients, 5 men and 5 women, with a mean age of 34 +/- 7 years, were included in the study. The dose of baclofen injected was 1000 micrograms between the ages of 16 and 55 years, 800 micrograms over the age of 55 years and 500 micrograms under the age of 16 years. The efficacy was assessed on the basis of the resolution of contractures and paroxysms and the initial dose was reinjected prior to the reappearance of these symptoms. Treatment was discontinued in the case of central nervous system depression or inefficacy. The first injection was effective in 9 cases for 24-48 h. The haemodynamic safety was always good. Five patients developed central depression with coma and respiratory depression, requiring artificial ventilation in 3 cases and reversed by flumazenil in 2 cases. Five patients were treated exclusively with baclofen with 4 cures. Five patients had to be ventilated with only one cure. This study confirms earlier studies concerning the efficacy of intrathecal baclofen in tetanus. However, the frequency of episodes of respiratory depression prevents the recommendation of repeated injections when respiratory intensive care facilities are not available. [ABSTRACT FROM AUTHOR]

N fixed in 16 cultivars of cowpea [ Vigna unguiculata (L.) Walp] inoculated with effective Bradyrhizobium strains collected from the West African MIRCEN culture collection was measured by 15N isotope dilution technique. In all plant parts, significant differences in the percentage of N derived from the atmosphere (%Ndfa) and the amount of Ndfa occurred between the cultivars. Ndoute variety exhibited the highest %Ndfa (74.33% in shoots; 60.90% in roots) and accumulated more fixed N (960 mg N plant–1 and 38 mg N plant–1 in shoots and roots, respectively). Therefore this cultivar should be selected as the highest N-fixing cowpea cultivar. It also should be used in a breeding programme to contribute to the development of cultivars that could stimulate an intensive use of cowpea in many different cropping systems in Africa with a view to maintaining soil fertility. [ABSTRACT FROM AUTHOR]

An abstract of the article "Childhood's chronic headache in children's national hospital of Albert Royer in Dakar" by L. B. Seck, N.S. Diagne, A. D. Sow, M. Ndiaye, L. Gueye, D. Sow, A. G. Diop and M. M . Ndaiye is presented.