38 research outputs found
Mapping 123 million neonatal, infant and child deaths between 2000 and 2017
Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations
Mapping geographical inequalities in childhood diarrhoeal morbidity and mortality in low-income and middle-income countries, 2000–17 : analysis for the Global Burden of Disease Study 2017
Background
Across low-income and middle-income countries (LMICs), one in ten deaths in children younger than 5 years is attributable to diarrhoea. The substantial between-country variation in both diarrhoea incidence and mortality is attributable to interventions that protect children, prevent infection, and treat disease. Identifying subnational regions with the highest burden and mapping associated risk factors can aid in reducing preventable childhood diarrhoea.
Methods
We used Bayesian model-based geostatistics and a geolocated dataset comprising 15 072 746 children younger than 5 years from 466 surveys in 94 LMICs, in combination with findings of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017, to estimate posterior distributions of diarrhoea prevalence, incidence, and mortality from 2000 to 2017. From these data, we estimated the burden of diarrhoea at varying subnational levels (termed units) by spatially aggregating draws, and we investigated the drivers of subnational patterns by creating aggregated risk factor estimates.
Findings
The greatest declines in diarrhoeal mortality were seen in south and southeast Asia and South America, where 54·0% (95% uncertainty interval [UI] 38·1–65·8), 17·4% (7·7–28·4), and 59·5% (34·2–86·9) of units, respectively, recorded decreases in deaths from diarrhoea greater than 10%. Although children in much of Africa remain at high risk of death due to diarrhoea, regions with the most deaths were outside Africa, with the highest mortality units located in Pakistan. Indonesia showed the greatest within-country geographical inequality; some regions had mortality rates nearly four times the average country rate. Reductions in mortality were correlated to improvements in water, sanitation, and hygiene (WASH) or reductions in child growth failure (CGF). Similarly, most high-risk areas had poor WASH, high CGF, or low oral rehydration therapy coverage.
Interpretation
By co-analysing geospatial trends in diarrhoeal burden and its key risk factors, we could assess candidate drivers of subnational death reduction. Further, by doing a counterfactual analysis of the remaining disease burden using key risk factors, we identified potential intervention strategies for vulnerable populations. In view of the demands for limited resources in LMICs, accurately quantifying the burden of diarrhoea and its drivers is important for precision public health
Fabrication of the SrFe11MnO19 / CoFe1.9Bi0.1O4 ferrite nanocomposite and investigation the properties of its microwave absorption in X-band
Research Paper: Synthesis of Bi1-xYxFe0.8Cu0. 2O3 Multiferroic Nanostructure by a Sol-gel Method and Investigating their Structural, Magnetic, and Dielectric Properties
In this research, first the bismuth ferrite nanostructure doped with Cu = 0.20 was prepared and then, its (Bi1-xYxFe0.80Cu0.20O3) doping with Y = 0.0, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30 by a sol-gel method at a temperature of 650 ºC and a 1 h were studied. The structural properties of the samples have been characterized using XRD, FESEM, FT-IR, and EDX. Investigations of the structural properties showed that by increasing the Y percentage, the peaks are broader and partly have disappeared due to their small size. The magnetic and dielectric properties of the samples using the analyses of VSM, and LCR meters have been investigated. Investigations of the magnetic properties showed that by increasing Y content, the sample's ferromagnetic properties gradually increased. So that the saturation magnetism of our work (2.5 emu/g) compared to the work of others (0.85 emu/g) significantly has increased. Also, the substitute of bismuth ferrite with yttrium and copper has led to the change of the site of Fe in the octahedral center of FeO6 and the change of the bond angle in O-Fe-O. It has created an asymmetry in the structure, which has improved the dielectric properties of the samples. The results of the dielectric properties showed that the dielectric constant, dielectric loss and electric conductivity in the samples doped with Y and Cu are more than in samples without doping
Magnetic and structure properties of Cd doping Bi-2223 superconductor
In this paper, Bi1.64-xPb0.36CdxSr2Ca2Cu3Oy (BPCSCCO) superconductor with x = 0.0, 0.02, 0.04 and 0.06 is made by the solid state reaction method. The magnetic susceptibility measurements were performed using AC susceptometer. The microstructure and morphology of the samples have been studied by X-ray diffraction, scanning electron microscope and energy dispersive X-ray. The results show that the partial substitution of Pb for Bi in the Bi-based superconductor increases the volume fraction of Bi-2223 phase. We also found that by doping of Cd, the high Tc phase is promoted and stabilized in the Bi-Pb-Sr-Ca-Cu-O system. The results of the X-Ray diffraction patterns and magnetic susceptibility measurements show that the low amount of Cd and long annealing time enhance the fraction of Bi-2223 phase. The maximum value volume fraction of Bi-2223 phase for sample with annealing time of 270 hours and 0.04 of Cd doping is obtaine
The Effect of Annealing Temperature on the Structural, Magnetic and Dielectric Properties of PbFe11.8Ni0.2O19 Nanoparticles
In this paper, Ni-doped lead hexaferrites (PbFe12-xNixO19) nanoparticles with x = 0.2 were prepared by sol- gel method. Then, the effect of annealing temperature on its structural, magnetic and dielectric properties was studied. First, the dryed gel was evaluated by Thermogravimetry-Differential Thermal Analysis (TG/DTA) and then, the structural morphology, magnetic and dielectric properties of samples have been characterized by Fourier Transform Infrared (FT-IR) spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Vibrating Sample Magnetometer (VSM) and LCR meter. The results of x-ray diffraction patterns show that by increasing annealing temperature up to 800 °C, PbFe11.8Ni0.2O19 phase percentage in the samples increases. Also, by increasing annealing temperature, the magnetization increases because the unwanted phases disappear and pure and single-phase lead hexaferrite are formed. By increasing frequency, first the AC electrical conductivity of the samples decreases and then increases. These variations have been explained by Maxwell- Wanger model. The result measurements show that the best sample is PbFe11.8Ni0.2O19 with annealing temperature of 800 °C for 3 h.
 
The effect of pH on the structural and magnetic properties of PbFe12O19 nanoparticles prepared by sol-gel method
In this research, lead hexaferrites nanoparticles (PbFe12O19) were prepared by sol-gel method. The effect of pH on the structural and magnetic properties of PbFe12O19 was studied. The attempt in this paper was to depict the effect of change in sol-gel pH on the size and morphology of the samples as well as their structural and magnetic properties. Therefore, samples with pH = 1.8, 3, 5, 6, 7, and 8 were prepared. Then, the dry gels of the samples were heated in the optimum annealing temperature and time of 800 oC and 3 h, respectively. In order to study the structural, morphological and magnetic properties of the samples prepared in various pHs X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Vibration Sample Magnetometer (VSM), and LCR meter were applied, respectivel
Improving the Recognition Percentage of the Identity Check System by Applying the SVM Method on the Face Image Using Special Faces
Face recognition has attracted tremendous attention during the last three decades because it is considered as a simple pattern recognition and image analysis method. Also, many facial recognition patterns have been introduced and used over the years. SVM algorithm has been one of the successful models in this field. In this article, we have introduced the special faces first. In the following, we have fully explained the SVM method and its subsets, including linear and non-linear support vector machines. suggestions for improving the recognition percentage of a person's identity check system by applying the SVM method on the face image using special faces are presented. For this test, 10 face images of 40 people (400 face images in total) have been selected from the ORL database. In this way, by choosing the optimal parameter C, determining the most suitable training samples, comparing more accurately with training images and using the distance with the closest training sample instead of the average distance, the proposed method has been implemented and tested on the famous ORL database. The obtained results are FAR=0.23% and FRR=0.48%, which shows the very high accuracy of the operation following the application of the above suggestions