Performance and Improvement of Various Antennas in Modern Wireless Communication System

Today, the importance of wireless communication is known around the world. To achieve better communication, many techniques and methods have been introduced. Among these techniques, intelligent / adaptive antennas are a hot topic in the field of research. Smart antennas consist of several antenna arrays and are able to optimize the radiation and reception of dynamically desired signals. In order to avoid or mitigate interference, smart antennas may also introduce zero values towards the receivers by adaptively updating the weights associated with each antenna element. Smart antennas can also improve reception quality and reduce missed calls. The various existing surveys are also discussed to identify the research deficit for the scope of future research

APPLICATION OF IPOM OEA BATATA STARCH MUCILAGE AS SUSPENDING AGENT IN OSELTAMIVIR SUSPENSION

Objective: The objective of the study was to search for a cheap and effective natural raw material that can serve as an alternative suspending agent in the formulation of oseltamivir suspension. The phytochemical and the physicochemical properties of the mucilage of Ipomoea batata starch were studied. Methods: The suspending properties of mucilage extract of I. batata starch was evaluated comparatively with that of acacia, xanthum gum and sodium alginate using model formulations at concentrations of 0.75, 1.5and 3.5% w/v. The Prepared suspensions were evaluated by studying different parameters like pH, sedimentation volume, redispersibility, Flow rate (F), viscosity, degree of flocculation, effect, effect of temperature and stability studies. Results: The results showed the presence of flavonoids, saponin, protein, carbohydrate and reducing sugars. The rheological properties of suspension showed that As the concentration of suspending agent increased viscosity also get increased which reduces the sedimentation and contributes to the stability of suspension. Increase in viscosity avoids the particle aggregation so particles remain in a flocculated state. While an increase in temperature did not significantly increased the viscosity of suspension. The order of stability of suspension in terms of sedimentation profile ranked thus: OF3 (3%w/v IBSM)>OF12 (3%w/v SA)>OF6 (3%w/v AG)>OF9 (3%w/v XG)>B (5%w/v potato starch). Conclusion: These results indicate that mucilage from I. batata starch in oseltamivir suspension has low sedimentation rate, medium viscosity and easily dispersible and can therefore serve as suspending agent in formulations of suspensions of sparingly soluble drugs

Low-Impedance 3D PEDOT:PSS Ultramicroelectrodes

The technology for producing microelectrode arrays (MEAs) has been developing since the 1970s and extracellular electrophysiological recordings have become well established in neuroscience, drug screening and cardiology. MEAs allow monitoring of long-term spiking activity of large ensembles of excitable cells noninvasively with high temporal resolution and mapping its spatial features. However, their inability to register subthreshold potentials, such as intrinsic membrane oscillations and synaptic potentials, has inspired a number of laboratories to search for alternatives to bypass the restrictions and/or increase the sensitivity of microelectrodes. In this study, we present the fabrication and in vitro experimental validation of arrays of PEDOT:PSS-coated 3D ultramicroelectrodes, with the best-reported combination of small size and low electrochemical impedance. We observed that this type of microelectrode does not alter neuronal network biological properties, improves the signal quality of extracellular recordings and exhibits higher selectivity toward single unit recordings. With fabrication processes simpler than those reported in the literature for similar electrodes, our technology is a promising tool for study of neuronal networks. \ua9 Copyright \ua9 2020 Jones, Moskalyuk, Barthold, Gut\uf6hrlein, Heusel, Schr\uf6ppel, Samba and Giugliano

Non-communicable diseases in the Western Area District, Sierra Leone, before and during the Ebola outbreak.

Setting: Twenty-seven peripheral health units, five secondary hospitals and one tertiary hospital, Western Area District, Sierra Leone. Objectives: To describe reporting systems, monthly attendances and facility-based patterns of six non-communicable diseases (NCDs) in the pre-Ebola and Ebola virus disease outbreak periods. Design: A cross-sectional study using programme data. Results: Reporting was 89% complete on the six selected NCDs pre-Ebola and 86% during the Ebola outbreak (P < 0.01). Overall, marked declining trends in NCDs were reported during the Ebola period, with a monthly mean of 342 cases pre-Ebola and 164 during the Ebola outbreak. The monthly mean number of cases per disease in the pre-Ebola and Ebola outbreak periods was respectively 228 vs. 85 for hypertension, 43 vs. 27 for cardiovascular diseases, 36 vs. 18 for diabetes and 25 vs. 29 for peptic ulcer disease; this last condition increased during the outbreak. There were higher proportions of NCDs among females during the Ebola outbreak compared with the pre-Ebola period. Except for peptic ulcer disease, the number of patients with NCDs declined by 25% in peripheral health units, 91% in the secondary hospitals and 70% in the tertiary hospital between the pre-Ebola and the Ebola outbreak periods. Conclusion: Comprehensive reporting of NCDs was suboptimal, and declined during the Ebola epidemic. There were decreases in reported attendances for NCDs between the pre-Ebola and the Ebola outbreak periods, which were even more marked in the hospitals. This study has important policy implications

Determinants of linear growth faltering among children with moderate-to-severe diarrhea in the global enteric multicenter study

Background: Moderate-to-severe diarrhea (MSD) in the first 2 years of life can impair linear growth. We sought to determine risk factors for linear growth faltering and to build a clinical prediction tool to identify children most likely to experience growth faltering following an episode of MSD.Methods: Using data from the Global Enteric Multicenter Study of children 0-23 months old presenting with MSD in Africa and Asia, we performed log-binomial regression to determine clinical and sociodemographic factors associated with severe linear growth faltering (loss of ≥ 0.5 length-for-age z-score [LAZ]). Linear regression was used to estimate associations with ΔLAZ. A clinical prediction tool was developed using backward elimination of potential variables, and Akaike Information Criterion to select the best fit model.Results: Of the 5902 included children, mean age was 10 months and 43.2% were female. Over the 50-90-day follow-up period, 24.2% of children had severe linear growth faltering and the mean ΔLAZ over follow-up was - 0.17 (standard deviation [SD] 0.54). After adjustment for age, baseline LAZ, and site, several factors were associated with decline in LAZ: young age, acute malnutrition, hospitalization at presentation, non-dysenteric diarrhea, unimproved sanitation, lower wealth, fever, co-morbidity, or an IMCI danger sign. Compared to children 12-23 months old, those 0-6 months were more likely to experience severe linear growth faltering (adjusted prevalence ratio [aPR] 1.97 [95% CI 1.70, 2.28]), as were children 6-12 months of age (aPR 1.72 [95% CI 1.51, 1.95]). A prediction model that included age, wasting, stunting, presentation with fever, and presentation with an IMCI danger sign had an area under the ROC (AUC) of 0.67 (95% CI 0.64, 0.69). Risk scores ranged from 0 to 37, and a cut-off of 21 maximized sensitivity (60.7%) and specificity (63.5%).Conclusion: Younger age, acute malnutrition, MSD severity, and sociodemographic factors were associated with short-term linear growth deterioration following MSD. Data routinely obtained at MSD may be useful to predict children at risk for growth deterioration who would benefit from interventions

Evaluation of seasonal malaria chemoprevention in two areas of intense seasonal malaria transmission: Secondary analysis of a household-randomised, placebo-controlled trial in Houndé District, Burkina Faso and Bougouni District, Mali.

BACKGROUND: Seasonal malaria chemoprevention (SMC) is now widely deployed in the Sahel, including several countries that are major contributors to the global burden of malaria. Consequently, it is important to understand whether SMC continues to provide a high level of protection and how SMC might be improved. SMC was evaluated using data from a large, household-randomised trial in Houndé, Burkina Faso and Bougouni, Mali. METHODS AND FINDINGS: The parent trial evaluated monthly SMC plus either azithromycin (AZ) or placebo, administered as directly observed therapy 4 times per year between August and November (2014-2016). In July 2014, 19,578 children aged 3-59 months were randomised by household to study group. Children who remained within the age range 3-59 months in August each year, plus children born into study households or who moved into the study area, received study drugs in 2015 and 2016. These analyses focus on the approximately 10,000 children (5,000 per country) under observation each year in the SMC plus placebo group. Despite high coverage and high adherence to SMC, the incidence of hospitalisations or deaths due to malaria and uncomplicated clinical malaria remained high in the study areas (overall incidence rates 12.5 [95% confidence interval (CI): 11.2, 14.1] and 871.1 [95% CI: 852.3, 890.6] cases per 1,000 person-years, respectively) and peaked in July each year, before SMC delivery began in August. The incidence rate ratio comparing SMC within the past 28 days with SMC more than 35 days ago-adjusted for age, country, and household clustering-was 0.13 (95% CI: 0.08, 0.20), P < 0.001 for malaria hospitalisations and deaths from malaria and 0.21 (95% CI 0.20, 0.23), P < 0.001 for uncomplicated malaria, indicating protective efficacy of 87.4% (95% CI: 79.6%, 92.2%) and 78.3% (95% CI: 76.8%, 79.6%), respectively. The prevalence of malaria parasitaemia at weekly surveys during the rainy season and at the end of the transmission season was several times higher in children who missed the SMC course preceding the survey contact, and the smallest prevalence ratio observed was 2.98 (95% CI: 1.95, 4.54), P < 0.001. The frequency of molecular markers of sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) resistance did not increase markedly over the study period either amongst study children or amongst school-age children resident in the study areas. After 3 years of SMC deployment, the day 28 PCR-unadjusted adequate clinical and parasitological response rate of the SP + AQ regimen in children with asymptomatic malaria was 98.3% (95% CI: 88.6%, 99.8%) in Burkina Faso and 96.1% (95% CI: 91.5%, 98.2%) in Mali. Key limitations of this study are the potential overdiagnosis of uncomplicated malaria by rapid diagnostic tests and the potential for residual confounding from factors related to adherence to the monthly SMC schedule. CONCLUSION: Despite strong evidence that SMC is providing a high level of protection, the burden of malaria remains substantial in the 2 study areas. These results emphasise the need for continuing support of SMC programmes. A fifth monthly SMC course is needed to adequately cover the whole transmission season in the study areas and in settings with similar epidemiology. TRIAL REGISTRATION: The AZ-SMC trial in which these data were collected was registered at clinicaltrials.gov: NCT02211729

Caractérisation de la diversité des microorganismes symbiotiques de Pterocarpus officinalis dans des forêts marécageuses de Guadeloupe et Martinique

We have isolated 17 strains of rhizobiums from nodules collected on roots of Pterocarpus officinalis in different sites of swamp forest in Guadeloupe and Martinique. The genotypic diversity of these strains were characterized by PCR-RFLP analysis of the IGS (intergenic spacer) region between 16S and 23S rRNA genes, by using two 4-base restriction endonucleases Hae III and Msp I. Results of IGS PCR-RFLP analysis showed that restriction patterns were similar for DNA extract from root nodules and cultures of rhizobium strains. The diversity of these strains varied from one site to another. They were grouped into 5 ribotypes by IGS PCR-RFLP analysis. Results of IGS sequence analysis showed that the 5 ribotypes are very close to the genus Bradyrhizobium. The symbiotic properties of the 5 ribotypes were evaluated on Acacia seyal, a plant test that is able to form nodules with several Bradyrhizobium species. One month and nineteen days after inoculation, the green colour of the leaves and the best growth of inoculated seedlings contrasting with the yellow colour of the leaves and the lowest growth of uninoculated seedlings, were the parameters indicating the level of nitrogen-fixing activity of the three Bradyrhizobium strains. Concurrently, the vesicular and arbuscular mycorrhizal status of P. officinalis was established. The two types of symbiotic microorganisms could contribute to mobilize available phosphorus and nitrogen for improving the growth of P. officinalis in degraded swamp forestsNous avons isolé 17 souches de rhizobiums à partir de nodules récoltés sur des racines de Pterocarpus officinalis dans différents sites de forêt marécageuse en Guadeloupe et Martinique. La diversité de ces souches a été caractérisée par PCR-RFLP de l'intergène IGS situé entre les gènes nucléaires codant pour les ARNr 16S et 23S en utilisant deux enzymes de restriction Hae III et Msp I. Des profils RFLP obtenus par digestion de l'IGS d'extraits d'ADN de nodules ou de cultures bactériennes sont comparables. L'analyse de ces profils RFLP a révélé une hétérogénéité génétique des souches qui varie suivant les sites. Les 17 souches de P. officinalis ont été groupées en 5 ribotypes par comparaison de leur profil RFLP. L'analyse phylogénétique de l'IGS a montré que ces ribotypes sont très proches du genre Bradyrhizobium. Les propriétés symbiotiques d'un représentant de chaque groupe de souches ont été testées sur Acacia seyal, espèce qui nodule avec un grand nombre d'espèces de Bradyrhizobium. Un mois et dix neuf jours après inoculation, l'observation de la vigueur et de la couleur verte des parties aériennes des plantes inoculées, comparativement aux plantes témoins peu vigoureuses et de couleur jaune, ont été des paramètres indiquant le caractère fixateur de trois souches de Bradyrhizobium. Parallélement, la présence de champignons mycorhiziens à vésicules et à arbuscules a été révélée sur des racines de P. officinalis. Ces deux types de symbiose pourraient agir en synergie sur la mobilisation du phosphore et de l'azote pour améliorer la croissance de P. officinalis dans des forêts marécageuses dégradées