33 research outputs found

    Novel results on Hermite-Hadamard kind inequalities for η\eta-convex functions by means of (k,r)(k,r)-fractional integral operators

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    We establish new integral inequalities of Hermite-Hadamard type for the recent class of η\eta-convex functions. This is done via generalized (k,r)(k,r)-Riemann-Liouville fractional integral operators. Our results generalize some known theorems in the literature. By choosing different values for the parameters kk and rr, one obtains interesting new results.Comment: This is a preprint of a paper whose final and definite form is a Springer chapter in the Book 'Advances in Mathematical Inequalities and Applications', published under the Birkhauser series 'Trends in Mathematics', ISSN: 2297-0215 [see http://www.springer.com/series/4961]. Submitted 02-Jan-2018; Revised 10-Jan-2018; Accepted 13-Feb-201

    Time-Fractional Optimal Control of Initial Value Problems on Time Scales

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    We investigate Optimal Control Problems (OCP) for fractional systems involving fractional-time derivatives on time scales. The fractional-time derivatives and integrals are considered, on time scales, in the Riemann--Liouville sense. By using the Banach fixed point theorem, sufficient conditions for existence and uniqueness of solution to initial value problems described by fractional order differential equations on time scales are known. Here we consider a fractional OCP with a performance index given as a delta-integral function of both state and control variables, with time evolving on an arbitrarily given time scale. Interpreting the Euler--Lagrange first order optimality condition with an adjoint problem, defined by means of right Riemann--Liouville fractional delta derivatives, we obtain an optimality system for the considered fractional OCP. For that, we first prove new fractional integration by parts formulas on time scales.Comment: This is a preprint of a paper accepted for publication as a book chapter with Springer International Publishing AG. Submitted 23/Jan/2019; revised 27-March-2019; accepted 12-April-2019. arXiv admin note: substantial text overlap with arXiv:1508.0075

    Public awareness and perception towards COVID-19 in sub-saharan African countries during the lockdown

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    Background: The coronavirus disease (COVID-19) outbreak has caused a universal health crisis resulting in significant morbidities and mortalities particularly among high-risk groups. This study sought to determine regional factors associated with knowledge and attitude towards COVID-19 mitigation practices and risk perception of contracting the disease in Sub-Saharan African (SSA) countries. Methods: A cross-sectional anonymous online study was conducted among 1970 participants between April and May 2020, during the lockdown in many SSA countries. Recruitment of participants was via WhatsApp, Facebook and emails using authors’ networks. The outcome variables were KAP (knowledge, attitudes and practice) of COVID-19 and analysis of variance (ANOVA) with post hoc test was run to assess the level of KAP by four regions in SSA. Simple and multiple linear regression (MLR) analyses were performed to examine factors associated with the outcome measures in the four SSA regions. Results: Mean knowledge (P=0.707) and risk perception (P=0.904) scores by four regions in SSA did not differ significantly. However, the mean attitude score was higher among West Africans compared with Southern (P=0.019) and Central Africans (P=0.003). MLR analysis revealed that among those living in West (adjusted coefficient β=-0.83 95% CI: -1.19, -0.48) and Southern Africa (β=-0.91 95% CI: -1.42, -0.40), having a primary or secondary education was associated with a decrease in knowledge scores while not being worried about COVID-19 decreased risk perception scores across the four SSA regions(West [β=-6.57, 95% CI: -7.53, -5.62], East [β=-6.24: 95% CI: -8.34,-4.15], Central [β=-6.51, 95% CI: -8.70, -4.31], and Southern Africa [β=-6.06: 95% CI: -7.51, -4.60]). Except among Southern Africans, participants who practiced self-isolation had positive attitude towards COVID-19. Conclusion: Future research on health education regarding COVID-19 or a future related pandemic in SSA should target people with lower education, those who do not self-isolate, those living in Southern and Western Africa and not worried about contracting COVID-19

    Factors affecting willingness to comply with public health measures during the pandemic among sub-Sahara Africans

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    Background: The unprecedented outbreak of coronavirus disease (COVID-19) drastically spread worldwide, resulting in extraordinary measures put in place in various countries including Sub Saharan Africa (SSA) countries. Objective: To assess the factors associated with compliance with the public health measures imposed by various SSA countries. Method: Cross sectional study using self-administered surveys distributed on social media platforms between April 18th and May 16th, 2020, corresponding with the mandatory lockdown period in most SSA countries. Multivariate analysis examined the associated factors. Results: The prevalence of hand hygiene, quarantine, self isolation practices, wearing of face mask and attending large gatherings during COVID-19 were 94%, 39%, 31%, 64% and 14%, respectively. In multivariate models, older age 49+ years: adjusted OR 2.13, 95%CI 1.22,3.71), females (OR 1.41,95%CI 1.03,1.93), Central African countries (OR 3.73,95%CI 2.02,6.87) were associated with wearing face mask. Living alone (aOR 1.52,95%CI 1.04,2.24) during the lockdown was associated with avoiding large gatherings including religious events. Female respondents (aOR 1.61, 95%CI 1.30, 2.00), married (aOR 1.71,95%CI 1.33,2.21) and unemployed (aOR 1.62,95%CI 1.25,2.09) SSAs were more likely to practice self-quarantine measures. Conclusion: The low prevalence of mitigation practices suggest the need for targeted education campaign programs to sensitise the population

    Differences in perceived risk of contracting SARS-CoV-2 during and after the lockdown in Sub-Saharan African countries

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    This study investigated risk perception of contracting and dying of SARS-CoV-2 in sub-Sahara Africa during and after the lockdown periods. Two online surveys were conducted one year apart, with participants 18 years and above living in sub-Sahara Africa or the diaspora. Each survey took four weeks. The first survey was taken from 18 April to 16 May 2020, i.e., during the lockdown. The second survey was taken from 14 April to 14 May 2021, i.e., after the lockdown. A cross-sectional study using adopted and modified questionnaires for both surveys were distributed through online platforms. Question about risks perception of contracting and dying of SARS-CoV-2 were asked. The Helsinki declaration was applied, and ethical approvals were obtained. Total responses for both surveys, i.e., both during and after the lockdown, was 4605. The mean age was similar in both surveys (18–28 years). The mean risk perception scores were higher after lockdown by 3.59%. Factors associated with risk perception of COVID-19 were survey period, age group, region of residence, and occupation. Non-health care workers had a lower risk perception of COVID-19. This first comparative study on the level of risk perception of Africans during and after the lockdown shows that one in every three and every four persons in sub-Sahara Africa felt at high risk of contracting COVID-19 and thought they could die from contracting the same, respectively

    COVID-19 in Sub-Saharan African countries : association between compliance and public opinion

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    Background: The outbreak of coronavirus disease (COVID-19) has created a global public health crisis and non-compliance with public health measures to contain the infection poses a challenge to Sub-Saharan African governments. This study investigated the associations between compliance and public opinion on COVID-19 public health containment measures across selected SSA countries. Method: Anonymous online cross-sectional survey was administered to 1779 adults (18 years and older) during the mandatory lockdown period in most African countries (April 18 - May 16, 2020). Respondents were recruited via Facebook, WhatsApp, and authors' networks. Data on participants’ socio-demographics, their opinions regarding the precautionary measures against COVID-19, and their compliance with preventive measures were collected. Multiple logistic regression analysis was used to examine the association between compliance and public opinions about COVID-19. Results: Respondents who did not think that public health authorities in their countries were doing enough to control the C0VID-19 outbreak were more likely to attend crowded places (aOR 1.75, 95% CI 1.30-2.35). Those who thought COVID-19 would not remain in their countries (aOR 0.48, 95% CI 0.24 - 0.96) and those who thought self-isolation is not needed during the pandemic (aOR 0.29, 95% CI 0.13 - 0.65) were less likely to encourage others to comply with the strategies put in place to prevent the spread of the disease. Participants who thought the COVID-19 outbreak was dangerous and those wearing medical masks were found to wash their hands with soap under running water. Conclusion: The study showed that public opinion influenced the compliance of individuals to public health measures for containment and mitigation of COVID-19. There is a need to improve compliance by the public

    Misinformation About COVID-19 in Sub-Saharan Africa: Evidence from a Cross-Sectional Survey

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    Misinformation about coronavirus disease 2019 (COVID-19) is a significant threat to global public health because it can inadvertently exacerbate public health challenges by promoting spread of the disease. This study used a convenience sampling technique to examine factors associated with misinformation about COVID-19 in sub-Saharan Africa using an online cross-sectional survey. A link to the online self-administered questionnaire was distributed to 1,969 participants through social media platforms and the authors' email networks. Four false statements—informed by results from a pilot study—were included in the survey. The participants' responses were classified as “Agree,” “Neutral,” and “Disagree.” A multinomial logistic regression was used to examine associated factors. Among those who responded to the survey, 19.3% believed that COVID-19 was designed to reduce world population, 22.2% thought the ability to hold your breath for 10 seconds meant that you do not have COVID-19, 27.8% believed drinking hot water flushes down the virus, and 13.9% thought that COVID-19 had little effect on Blacks compared with Whites. An average of 33.7% were unsure whether the 4 false statements were true. Multivariate analysis revealed that those who thought COVID-19 was unlikely to continue in their countries reported higher odds of believing in these 4 false statements. Other significant factors associated with belief in misinformation were age (older adults), employment status (unemployed), gender (female), education (bachelor's degree), and knowledge about the main clinical symptoms of COVID-19. Strategies to reduce the spread of false information about COVID-19 and other future pandemics should target these subpopulations, especially those with limited education. This will also enhance compliance with public health measures to reduce spread of further outbreaks

    Tick-, Flea-, and Louse-Borne Diseases of Public Health and Veterinary Significance in Nigeria

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    Mosquito-borne diseases are common high-impact diseases in tropical and subtropical areas. However, other non-mosquito vector-borne pathogens (VBPs) may share their geographic distribution, seasonality, and clinical manifestations, thereby contributing their share to the morbidity and mortality caused by febrile illnesses in these regions. The purpose of this work was to collect and review existing information and identify knowledge gaps about tick, flea-, and louse-borne diseases of veterinary and public health significance in Nigeria. Full-length articles about VBPs were reviewed and relevant information about the vectors, their hosts, geographic distribution, seasonality, and association(s) with human or veterinary diseases was extracted. Specific laboratory tools used for detection and identification of VBPs in Nigeria were also identified. A total of 62 original publications were examined. Substantial information about the prevalence and impacts of ticks and fleas on pet and service dogs (18 articles), and livestock animals (23 articles) were available; however, information about their association with and potential for causing human illnesses was largely absent despite the zoonotic nature of many of these peri-domestic veterinary diseases. Recent publications that employed molecular methods of detection demonstrated the occurrence of several classic (Ehrlichia canis, Rickettsia africae, Bartonella sp.) and emerging human pathogens (R. aeschlimannii, Neoehrlichia mikurensis) in ticks and fleas. However, information about other pathogens often found in association with ticks (R. conorii) and fleas (R. typhi, R. felis) across the African continent was lacking. Records of louse-borne epidemic typhus in Nigeria date to 1947; however, its current status is not known. This review provides an essential baseline summary of the current knowledge in Nigeria of non-mosquito VBPs, and should stimulate improvements in the surveillance of the veterinary and human diseases they cause in Nigeria. Due to increasing recognition of these diseases in other African countries, veterinary and public health professionals in Nigeria should expand the list of possible diseases considered in patients presenting with fever of unknown etiology

    Factors associated with the myth about 5G network during COVID-19 pandemic in sub-Saharan Africa

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    Background: Globally, the conspiracy theory claiming 5G technology can spread the coronavirus disease (COVID-19) is making the rounds on social media and this could have a significant effect in tackling the spread of the pandemic. This study investigated the impact of the myth that 5G technology is linked to COVID-19 pandemic among sub-Saharan Africans (SSA). Methods: A cross-sectional survey was administered on 2032 participants between April 18 - May 16, 2020, corresponding to the mandatory lockdown period in some SSA countries (April 18 - May 16, 2020). Participants were recruited via Facebook, WhatsApp, and authors’ emails. The outcome measure was whether respondent believed that 5G technology was the cause of the coronavirus outbreak or not. Multiple logistic regression analyses using backward stepwise were used to examine the associated factors. Results: About 7.3% of the participants believed that 5G technology was behind the COVID-19 pandemic. Participants from Central Africa reported the highest proportion (14.4%) while the lowest proportion (5.4%) was among those from Southern Africa. After adjusting for potential covariates in the multivariate analysis, Central Africans (adjusted odds ratio, AOR 2.12; 95% confidence interval, CI=1.20-3.75), females (AOR 1.86; 95% CI=1.20-2.84) and those who were unemployed at the time of this study (AOR 1.91; 95% CI=1.08-3.36) were more likely to believe in the myth that 5G technology was linked to the COVID-19 pandemic. Participants who felt that COVID-19 pandemic will not continue in their country were 1.59 times (95% CI=1.04-2.45) more likely to associate the 5G technology with COVID-19 compared to those who thought that the disease will remain after the lockdown. Participants who were younger were more likely to believe in the 5G technology myth but the association between level of education and belief that 5G technology was associated with COVID-19 which was significant in the univariate analysis (unadjusted odds ratio OR 1.69; 95CI =1.02, 2.80), was nullified after adjustments for all potential confounders. Conclusions: This study found that 7.4% of adult participants from SSA held the belief that 5G technology was linked to COVID-19 pandemic. Public health interventions including health education strategies to address the myth that 5G was linked COVID-19 pandemic in SSA are needed and such intervention should target participants who do not believe that COVID-19 pandemic will continue in their country, females, those that are unemployed and those from Central African countries in order to minimize further spread of the disease in the region
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