scholarly journals The Typhoid Fever Surveillance in Africa Program: Geospatial Sampling Frames for Household-based Studies: Lessons Learned From a Multicountry Surveillance Network in Senegal, South Africa, and Sudan

2019 ◽  
Vol 69 (Supplement_6) ◽  
pp. S474-S482
Author(s):  
Stephen Baker ◽  
Mohammad Ali ◽  
Jessica Fung Deerin ◽  
Muna Ahmed Eltayeb ◽  
Ligia Maria Cruz Espinoza ◽  
...  
Keyword(s):  
South Africa ◽  
Satellite Imagery ◽  
Population Based ◽  
Google Earth ◽  
Lessons Learned ◽  
Data Availability ◽  
Sampling Frame ◽  
Positional Accuracy ◽  
Surveillance Network ◽  
Mean Square Errors

Abstract Background Robust household sampling, commonly applied for population-based investigations, requires sampling frames or household lists to minimize selection bias. We have applied Google Earth Pro satellite imagery to constitute structure-based sampling frames at sites in Pikine, Senegal; Pietermaritzburg, South Africa; and Wad-Medani, Sudan. Here we present our experiences in using this approach and findings from assessing its applicability by determining positional accuracy. Methods Printouts of satellite imagery combined with Global Positioning System receivers were used to locate and to verify the locations of sample structures (simple random selection; weighted-stratified sampling). Positional accuracy was assessed by study site and administrative subareas by calculating normalized distances (meters) between coordinates taken from the sampling frame and on the ground using receivers. A higher accuracy in conjunction with smaller distances was assumed. Kruskal-Wallis and Dunn multiple pairwise comparisons were performed to evaluate positional accuracy by setting and by individual surveyor in Pietermaritzburg. Results The median normalized distances and interquartile ranges were 0.05 and 0.03–0.08 in Pikine, 0.09 and 0.05–0.19 in Pietermaritzburg, and 0.05 and 0.00–0.10 in Wad-Medani, respectively. Root mean square errors were 0.08 in Pikine, 0.42 in Pietermaritzburg, and 0.17 in Wad-Medani. Kruskal-Wallis and Dunn comparisons indicated significant differences by low- and high-density setting and interviewers who performed the presented approach with high accuracy compared to interviewers with poor accuracy. Conclusions The geospatial approach presented minimizes systematic errors and increases robustness and representativeness of a sample. However, the findings imply that this approach may not be applicable at all sites and settings; its success also depends on skills of surveyors working with aerial data. Methodological modifications are required, especially for resource-challenged sites that may be affected by constraints in data availability and area size.

scholarly journals The HPAfrica protocol: Assessment of health behaviour and population-based socioeconomic, hygiene behavioural factors - a standardised repeated cross-sectional study in multiple cohorts in sub-Saharan Africa

BMJ Open ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. e021438 ◽  
Author(s):  
Gi Deok Pak ◽  
Andrea Haekyung Haselbeck ◽  
Hyeong Won Seo ◽  
Isaac Osei ◽  
John Amuasi ◽  
...  
Keyword(s):  
Health Behaviour ◽  
Disease Burden ◽  
Healthcare Facility ◽  
Population Based ◽  
Google Earth ◽  
Sub Saharan Africa ◽  
Sampling Frame ◽  
Sampling Weights ◽  
Cross Sectional ◽  
Study Population

IntroductionThe objective of the Health Population Africa (HPAfrica) study is to determine health behaviour and population-based factors, including socioeconomic, ethnographic, hygiene and sanitation factors, at sites of the Severe Typhoid Fever in Africa (SETA) programme. SETA aims to investigate healthcare facility-based fever surveillance in Burkina Faso, the Democratic Republic of the Congo, Ethiopia, Ghana, Madagascar and Nigeria. Meaningful disease burden estimates require adjustment for health behaviour patterns, which are assumed to vary among a study population.Methods and analysisFor the minimum sample size of household interviews required, the assumptions of an infinite population, a design effect and age-stratification and sex-stratification are considered. In the absence of a population sampling frame or household list, a spatial approach will be used to generate geographic random points with an Aeronautical Reconnaissance Coverage Geographic Information System tool. Printouts of Google Earth Pro satellite imagery visualise these points. Data of interest will be assessed in different seasons by applying population-weighted stratified sampling. An Android-based application and a web service will be developed for electronic data capturing and synchronisation with the database server in real time. Sampling weights will be computed to adjust for possible differences in selection probabilities. Descriptive data analyses will be performed in order to assess baseline information of each study population and age-stratified and sex-stratified health behaviour. This will allow adjusting disease burden estimates. In addition, multivariate analyses will be applied to look into associations between health behaviour, population-based factors and the disease burden as determined in the SETA study.Ethics and disseminationEthic approvals for this protocol were obtained by the Institutional Review Board of the International Vaccine Institute (No. 2016–0003) and by all collaborating institutions of participating countries. It is anticipated to disseminate findings from this study through publication on a peer-reviewed journal.

scholarly journals Geophysical changes detection by remote sensing in Alaminos River Pangasinan, Philippines

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Annie Melinda Paz-Alberto 1 ◽  
Edmark P. Bulaong 1 ◽  
Ranilo B. Lao 1 ◽  
Eleazar V. Raneses 1 ◽  
Bennidict P. Pueyo 1
Keyword(s):  
Historical Data ◽  
Google Earth ◽  
Positional Accuracy ◽  
Natural Factor ◽  
Sea Levels ◽  
The North ◽  
Changes Detection ◽  
Mean Square Errors ◽  
North And South ◽  
Heavy Rains

Geophysical changes of the river outlets, riverbanks and coastlines in Alaminos, Pangasinan were measured using Google Earth from 2009 to 2014. On the other hand, actual measurements were gathered using South Total Station (NTS-362R6L) in 2015. The insights of the residents regarding feature changes of the river were obtained through one on one interview. Root Mean Square Errors (RMSE) were computed for measurement and horizontal positional accuracy of Google Earth. To perceive the effects of sea levels, historical data (2004-2015) from Bolinao, Philippines Tide Chart at online tides and currents predictions were also analyzed. Alaminos river outlets decreased in width size due to natural factor and human activities. Alaminos riverbank increased in width size which could be possibly due to natural calamities and weak bank resistance brought about by the frequent flooding caused by heavy rains and the emergency released of water from San Roque Dam. Generally the north and south coasts of Alaminos River increased and expanded. Rise in sea level is also a probable cause of changes wherein heights of low tides in Pangasinan Gulf is increasing overtime. The computed RMSE was low which indicate positional accuracy and measurement of Google Earth in the study area.

scholarly journals LARGE SCALE CITY MAPPING USING SATELLITE IMAGERY / KOSMINIŲ NUOTRAUKŲ IŠ GOOGLE EARTH, TAIKOMŲ MIESTAMS KARTOGRAFUOTI STAMBIUOJU MASTELIU, REKTIFIKAVIMAS / РЕКТИФИКАЦИЯ КОСМИЧЕСКИХ СНИМКОВ ИЗ GOOGLE EARTH ДЛЯ КРУПНОМАСШТАБНОГО КАРТОГРАФИРОВАНИЯ ГОРОДОВ

2012 ◽  
Vol 37 (4) ◽  
pp. 168-171 ◽  
Author(s):  
Birutė Ruzgienė ◽  
Qian Yi Xiang ◽  
Silvija Gečytė
Keyword(s):  
Satellite Imagery ◽  
Large Scale ◽  
Modern Technology ◽  
Google Earth ◽  
Aerial Images ◽  
Control Points ◽  
Image Rectification ◽  
Image Deformation ◽  
Map Construction ◽  
Short Period

The rectification of high resolution digital aerial images or satellite imagery employed for large scale city mapping is modern technology that needs well distributed and accurately defined control points. Digital satellite imagery, obtained using widely known software Google Earth, can be applied for accurate city map construction. The method of five control points is suggested for imagery rectification introducing the algorithm offered by Prof. Ruan Wei (tong ji University, Shanghai). Image rectification software created on the basis of the above suggested algorithm can correct image deformation with required accuracy, is reliable and keeps advantages in flexibility. Experimental research on testing the applied technology has been executed using GeoEye imagery with Google Earth builder over the city of Vilnius. Orthophoto maps at the scales of 1:1000 and 1:500 are generated referring to the methodology of five control points. Reference data and rectification results are checked comparing with those received from processing digital aerial images using a digital photogrammetry approach. The image rectification process applying the investigated method takes a short period of time (about 4-5 minutes) and uses only five control points. The accuracy of the created models satisfies requirements for large scale mapping. Santrauka Didelės skiriamosios gebos skaitmeninių nuotraukų ir kosminių nuotraukų rektifikavimas miestams kartografuoti stambiuoju masteliu yra nauja technologija. Tai atliekant būtini tikslūs ir aiškiai matomi kontroliniai taškai. Skaitmeninės kosminės nuotraukos, gautos taikant plačiai žinomą programinį paketą Google Earth, gali būti naudojamos miestams kartografuoti dideliu tikslumu. Siūloma nuotraukas rektifikuoti Penkių kontrolinių taskų metodu pagal prof. Ruan Wei (Tong Ji universitetas, Šanchajus) algoritmą. Moksliniam eksperimentui pasirinkta Vilniaus GeoEye nuotrauka iš Google Earth. 1:1000 ir 1:500 mastelio ortofotografiniai žemėlapiai sudaromi Penkių kontrolinių taškų metodu. Rektifikavimo duomenys lyginami su skaitmeninių nuotraukų apdorojimo rezultatais, gautais skaitmeninės fotogrametrijos metodu. Nuotraukų rektifikavimas Penkių kontrolinių taskų metodu atitinka kartografavimo stambiuoju masteliu reikalavimus, sumažėja laiko sąnaudos. Резюме Ректификация цифровых и космических снимков высокой резолюции для крупномасштабного картографирования является новой технологией, требующей точных и четких контрольных точек. Цифровые космические снимки, полученные с использованием широкоизвестного программного пакета Google Earth, могут применяться для точного картографирования городов. Для ректификации снимков предложен метод пяти контрольных точек с применением алгоритма проф. Ruan Wei (Университет Tong Ji, Шанхай). Для научного эксперимента использован снимок города Вильнюса GeoEye из Google Earth. Ортофотографические карты в масштабе 1:1000 и 1:500 генерируются с применением метода пяти контрольных точек. Полученные результаты и данные ректификации сравниваются с результатами цифровых снимков, полученных с применением метода цифровой фотограмметрии. Ректификация снимков с применением метода пяти контрольных точек уменьшает временные расходы и удовлетворяет требования, предъявляемые к крупномасштабному картографированию.

The Economic Cost of Violence Against Women and Girls in Low- and Middle-Income Countries: A Systematic Review of the Evidence

2021 ◽  
pp. 152483802110160
Author(s):  
Seema Vyas ◽  
Melissa Meinhart ◽  
Katrina Troy ◽  
Hannah Brumbaum ◽  
Catherine Poulton ◽  
...  
Keyword(s):  
South Africa ◽  
Systematic Review ◽  
Violence Against Women ◽  
Economic Burden ◽  
Data Availability ◽  
Female Genital Cutting ◽  
Middle Income ◽  
Middle Income Countries ◽  
Women And Girls ◽  
Low And Middle Income

Evidence demonstrating the economic burden of violence against women and girls can support policy and advocacy efforts for investment in violence prevention and response programming. We undertook a systematic review of evidence on the costs of violence against women and girls in low- and middle-income countries published since 2005. In addition to understanding costs, we examined the consistency of methodological approaches applied and identified and assessed common methodological issues. Thirteen articles were identified, eight of which were from sub-Saharan Africa. Eight studies estimated costs associated with domestic or intimate partner violence, others estimated the costs of interpersonal violence, female genital cutting, and sexual assaults. Methodologies applied to estimate costs were typically based on accounting approaches. Our review found that out-of-pocket expenditures to individuals for seeking health care after an episode of violence ranged from US$29.72 (South Africa) to US$156.11 (Romania) and that lost productivity averaged from US$73.84 to US$2,151.48 (South Africa) per facility visit. Most studies that estimated provider costs of service delivery presented total programmatic costs, and there was variation in interventions, scale, and resource inputs measured which hampered comparability. Variations in methodological assumptions and data availability also made comparisons across countries and settings challenging. The limited scope of studies in measuring the multifaceted impacts of violence highlights the challenges in identifying cost metrics that extend beyond specific violence episodes. Despite the limited evidence base, our assessment leads us to conclude that the estimated costs of violence against women and girls are a fraction of its true economic burden.

Surrounding Vehicles’ Contribution to Car-Following Models: Deep-Learning-Based Analysis

2021 ◽  
pp. 036119812110186
Author(s):  
Saeed Vasebi ◽  
Yeganeh M. Hayeri ◽  
Peter J. Jin
Keyword(s):  
Deep Learning ◽  
Traffic Flow ◽  
Short Term Memory ◽  
Data Availability ◽  
Car Following ◽  
Preceding Vehicle ◽  
Long Short Term Memory ◽  
The Right ◽  
Mean Square Errors ◽  
Deep Learning Model

Relatively recent increased computational power and extensive traffic data availability have provided a unique opportunity to re-investigate drivers’ car-following (CF) behavior. Classic CF models assume drivers’ behavior is only influenced by their preceding vehicle. Recent studies have indicated that considering surrounding vehicles’ information (e.g., multiple preceding vehicles) could affect CF models’ performance. An in-depth investigation of surrounding vehicles’ contribution to CF modeling performance has not been reported in the literature. This study uses a deep-learning model with long short-term memory (LSTM) to investigate to what extent considering surrounding vehicles could improve CF models’ performance. This investigation helps to select the right inputs for traffic flow modeling. Five CF models are compared in this study (i.e., classic, multi-anticipative, adjacent-lanes, following-vehicle, and all-surrounding-vehicles CF models). Performance of the CF models is compared in relation to accuracy, stability, and smoothness of traffic flow. The CF models are trained, validated, and tested by a large publicly available dataset. The average mean square errors (MSEs) for the classic, multi-anticipative, adjacent-lanes, following-vehicle, and all-surrounding-vehicles CF models are 1.58 × 10−3, 1.54 × 10−3, 1.56 × 10−3, 1.61 × 10−3, and 1.73 × 10−3, respectively. However, the results show insignificant performance differences between the classic CF model and multi-anticipative model or adjacent-lanes model in relation to accuracy, stability, or smoothness. The following-vehicle CF model shows similar performance to the multi-anticipative model. The all-surrounding-vehicles CF model has underperformed all the other models.

scholarly journals Measurement properties of the construct of the code of ethics content: The South African experience

2018 ◽  
Vol 49 (1) ◽  
Author(s):  
Mercy Mpinganjira ◽  
Mornay Roberts-Lombard ◽  
Goran Svensson ◽  
Greg Wood
Keyword(s):  
South Africa ◽  
South African ◽  
Goodness Of Fit ◽  
Code Of Ethics ◽  
Codes Of Ethics ◽  
Measurement Model ◽  
Measurement Properties ◽  
Survey Method ◽  
Research Approach ◽  
Sampling Frame

Background: Many organisations develop codes of ethics to help guide business conduct. However, not much is known about the contents of codes of ethics. Objectives: This article aims at investigating the code of ethics content construct and its measurement properties using a sample of firms from South Africa. Method: The study followed a quantitative research approach. The sampling frame consisted of the top 500 companies in South Africa. A structured questionnaire was administered using the telephone survey method. The respondents consisted of company secretaries and heads or managers responsible for ethics in the respective companies. At the end of the data collection period, a total of 222 usable responses were obtained. Results: The findings show that South African top companies have comprehensive codes of ethics as evidenced by the high mean values obtained from all of the content items under investigation. The findings also support the notion that the code of ethics content construct is multidimensional. Seven different dimensions were confirmed in the analysis. The measurement model of the ethics content construct was found to be valid as evidenced by the goodness-of-fit measure and measures of validity. Conclusion: The study shows that the code of ethics construct is multi-dimensional in nature. The framework provided in this study can also be used in developing, evaluating and strengthening existing codes where such need arises. This study contributes to theory on business ethics and presents the first tested measurement model of the code of ethics construct in South Africa.

scholarly journals Trends in Antifungal Drug Susceptibility of Cryptococcus neoformans Isolates Obtained through Population-Based Surveillance in South Africa in 2002-2003 and 2007-2008

2011 ◽  
Vol 55 (6) ◽  
pp. 2606-2611 ◽  
Author(s):  
Nelesh P. Govender ◽  
Jaymati Patel ◽  
Marelize van Wyk ◽  
Tom M. Chiller ◽  
Shawn R. Lockhart ◽  
...  
Keyword(s):  
South Africa ◽  
Cryptococcus Neoformans ◽  
Amphotericin B ◽  
Fungal Infections ◽  
Antifungal Susceptibility ◽  
Drug Susceptibility ◽  
Population Based ◽  
Content Type ◽  
Microdilution Method ◽  
Broth Microdilution Method

ABSTRACTCryptococcus neoformansis the most common cause of meningitis among adult South Africans with HIV infection/AIDS. Widespread use of fluconazole for treatment of cryptococcal meningitis and other HIV-associated opportunistic fungal infections in South Africa may lead to the emergence of isolates with reduced fluconazole susceptibility. MIC testing using a reference broth microdilution method was used to determine if isolates with reduced susceptibility to fluconazole or amphotericin B had emerged among cases of incident disease. Incident isolates were tested from two surveillance periods (2002-2003 and 2007-2008) when population-based surveillance was conducted in Gauteng Province, South Africa. These isolates were also tested for susceptibility to flucytosine, itraconazole, voriconazole, and posaconazole. Serially collected isolate pairs from cases at several large South African hospitals were also tested for susceptibility to fluconazole. Of the 487 incident isolates tested, only 3 (0.6%) demonstrated a fluconazole MIC of ≥16 μg/ml; all of these isolates were from 2002-2003. All incident isolates were inhibited by very low concentrations of amphotericin B and exhibited very low MICs to voriconazole and posaconazole. Of 67 cases with serially collected isolate pairs, only 1 case was detected where the isolate collected more than 30 days later had a fluconazole MIC value significantly higher than the MIC of the corresponding incident isolate. Although routine antifungal susceptibility testing of incident isolates is not currently recommended in clinical settings, it is still clearly important for public health to periodically monitor for the emergence of resistance.

Justice versus Social Justice in South Africa: Quo vadis?

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Marelize Isabel Schoeman
Keyword(s):  
South Africa ◽  
Social Justice ◽  
Criminal Justice ◽  
Criminal Justice System ◽  
Justice System ◽  
Lessons Learned ◽  
Historical Discourse ◽  
Self Reflection ◽  
Underlying Basis ◽  
Quo Vadis

This article explores the concept of criminal justice as a formal process in which parties are judged and often adjudged from the paradigmatic perspective of legal guilt versus legal innocence. While this function of a criminal-justice system is important – and indeed necessary – in any ordered society, a society in transition such as South Africa must question the underlying basis of justice. This self-reflection must include an overview questioning whether the criminal-justice system and its rules are serving the community as originally intended or have become a self-serving function of state in which the final pursuit is outcome-driven as opposed to process-driven. The process of reflection must invariably find its genesis in the question: ‘What is justice?’ While this rhetorical phraseology has become trite through overuse, the author submits that the question remains of prime importance when considered contemporarily but viewed through the lens of historical discourse in African philosophy. In essence, the question remains unanswered. Momentum is added to this debate by the recent movement towards a more human rights and restorative approach to justice as well as the increased recognition of traditional legal approaches to criminal justice. This discussion is wide and in order to delimit its scope the author relies on a Socratically influenced method of knowledge-mining to determine the philosophical principles underpinning the justice versus social justice discourse. It is proposed that lessons learned from African philosophies about justice and social justice can be integrated into modern-day justice systems and contribute to an ordered yet socially oriented approach to justice itself.

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