scholarly journals Effect of Petroleum Products on the Larvicidal Activity of Aedes Mosquitoes in Ika North-East LGA, Delta State, Nigeria

2021 ◽  
Vol 14 (1) ◽  
pp. 24-30
Author(s):  
Cynthia C. Ojianwuna ◽  
Victor N. Enwemiwe ◽  
Sunny E. Erhunmwun
Keyword(s):  
Larvicidal Activity ◽  
Large Scale ◽  
Mosquito Species ◽  
Disease Outbreaks ◽  
Scaling Up ◽  
Petroleum Products ◽  
Probit Analysis ◽  
North East ◽  
Aedes Mosquitoes ◽  
Larvae Density

Aims: The recent yellow fever outbreak in Delta State, especially in Ika North East local government, triggered the need for this study. Background: Diseases caused by Aedes are by far raising serious concerns in the world. Objective: To evaluate the larvicidal activity on the use of petroleum products in the control of Aedes mosquitoes. Methods: Mosquito species were collected using 350ml deep ladle and identified in the field using their resting positions in their local habitats. Larvae and pupae were separately exposed to 0.005, 0.01, and 0.02%ml of kerosene and petrol in single and mixed forms. The experimental sets were triplicated. Data was analyzed using ANOVA and Turkey’s test to compare mortality, and time of mortality. LC50 and LC95 were computed using Probit analysis. Results: Results revealed that all concentrations of treatment caused complete mortality in larvae except in 0.005%ml and 0.01%ml of kerosene alone and kerosene and petrol mixture at 50 minutes of exposure. All concentrations of treatment equally caused complete mortality in pupae except in 0.005%ml of kerosene (Mean= 10.00) at 30 minutes. The differences between mortality and time mortality records were significant (p< 0.05). Kerosene and petrol mixture and kerosene alone had the lower LC50 and LC95 0.0021 and 0.0088ml respectively in the larvae group. Kerosene and petrol mixture had lower LC50 and LC95 0.0037 and 0.0050, respectively. Conclusion: Therefore, scaling up this intervention on a large scale in endemic areas would reduce larvae density and disease outbreaks.

scholarly journals Chemical Composition and Larvicidal Activity of Mentha pulegium ssential Oil from Central Morocco Against Larvae of Mosquito Culex pipiens (Diptera: Culicidae)

2018 ◽  
Vol 9 (07) ◽  
Author(s):  
Fouad El-Akhal ◽  
Yassine Ezzoubi ◽  
Taghzouti Khalid ◽  
Abdelhakim El Ouali Lalami
Keyword(s):  
Essential Oil ◽  
Larvicidal Activity ◽  
Culex Pipiens ◽  
Mosquito Species ◽  
Probit Analysis ◽  
World Health ◽  
Mentha Pulegium ◽  
The North ◽  
Medicinal Plant Extracts ◽  
Lc50 And Lc90

Background: In Morocco, the species Culex pipiens (Diptera: Culicidae) has developed resistance to the synthetic insecticide. Therefore, there is an urgent need to find alternatives to the insecticides, as natural herbal biocides. Objective: The essential oil of Mentha pulegium grown the North center of in Morocco has been analyzed and their larvicidal activity on Culex pipiens was determined. Methods: The analysis and the identification of the various constituents of essential oilobtained by hydro-distillation of the aerial part were carried out by Gas Chromatography coupled with Mass Spectrometry (GC/MS). Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The larvicidal activity of medicinal plant extracts were tested against early fourth-instar larvae of Culex pipiens. The repellent efficacy was determined against of mosquito species (Culex pipiens) at six concentration’s (5, 10, 20, 40, 80 and 160 ppm) under the laboratory condition. The mortality was observed 24h after treatment; data were subjected to probit analysis to determine the Lethal Concentrations (LC50 and LC90) to kill 50 and 90 percent of the treated larvae of tested species. Results: The major constituents of Mentha pulegium essential oil were identified as pulegone (53.23%), α-pinene (12.1%), piperitone (9.62%), menthone (9.26) and piperitenone (6.6%). The LC50 and LC90 were estimated at 25.45 ppm and 98.66 ppm respectively. Conclusion: This investigation indicates that the Mentha pulegium essential oil could serve as a potential larvicidal and could be used as an ideal ecofriendly approach for the control of the Culex pipiens.

A Simple PCR Assay for Discrimination of Dengue Vectors from Nsukka LGA, Nigeria

2020 ◽  
Vol 10 (1) ◽  
pp. 67-77
Author(s):  
Amos Watentena ◽  
Ikem Chris Okoye ◽  
Ikechukwu Eugene Onah ◽  
Onwude Cosmas Ogbonnaya ◽  
Emmanuel Ogudu
Keyword(s):  
Aedes Aegypti ◽  
Aedes Albopictus ◽  
Mosquito Species ◽  
Public Health Problem ◽  
Major Public Health Problem ◽  
Mosquito Vector ◽  
Aedes Mosquitoes ◽  
Allele Specific ◽  
Arboviral Diseases ◽  
Dengue Vectors

Mosquitoes of Aedes species are vectors of several arboviral diseases which continue to be a major public health problem in Nigeria. This study among other things, morphologically identified Aedes mosquitoes collected from Nsukka LGA and used an allele specific PCR amplification for discrimination of dengue vectors. Larval sampling, BG-sentinel traps and modified human landing catches were used for mosquito sampling in two selected autonomous communities of Nsukka LGA (Nsukka and Obimo). A total of 124 Aedes mosquitoes consisting of five (5) different species were collected from April to June, 2019 in a cross-sectional study that covered 126 households, under 76 distinct geographical coordinates. Larvae was mainly collected from plastic containers 73% (n=224), metallic containers 14% (n=43), earthen pots 9% (n=29) and used car tyres 3% (n=9), reared to adult stage 69.35% (n=86), and all mosquitoes were identified using standard morphological keys. Five (5) Aedes mosquito species were captured; Aedes aegypti 83(66.94%), Aedes albopictus 33(26.61%), Aedes simpsoni (4.48%), Aedes luteocephalus (≤1%) and Aedes vittatus (≤1%). Nsukka autonomous community had higher species diversity than Obimo. Allele specific amplification confirmed dengue vectors, Aedes aegypti and Aedes albopictus species on a 2% agarose gel. Since the most recent re-emergence of arboviral diseases is closely associated with Aedes species, findings of this study, therefore, give further evidence about the presence of potential arboviral vectors in Nigeria and describe the role of a simple PCR in discriminating some. Further entomological studies should integrate PCR assays in mosquito vector surveillance.

scholarly journals Digital proximity tracing on empirical contact networks for pandemic control

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
G. Cencetti ◽  
G. Santin ◽  
A. Longa ◽  
E. Pigani ◽  
A. Barrat ◽  
...  
Keyword(s):  
Large Scale ◽  
Disease Outbreaks ◽  
Physical Distance ◽  
Contact Tracing ◽  
Reproductive Number ◽  
Modeling Framework ◽  
Infectious Disease Outbreaks ◽  
Contact Patterns ◽  
Contact Data ◽  
The Impact

AbstractDigital contact tracing is a relevant tool to control infectious disease outbreaks, including the COVID-19 epidemic. Early work evaluating digital contact tracing omitted important features and heterogeneities of real-world contact patterns influencing contagion dynamics. We fill this gap with a modeling framework informed by empirical high-resolution contact data to analyze the impact of digital contact tracing in the COVID-19 pandemic. We investigate how well contact tracing apps, coupled with the quarantine of identified contacts, can mitigate the spread in real environments. We find that restrictive policies are more effective in containing the epidemic but come at the cost of unnecessary large-scale quarantines. Policy evaluation through their efficiency and cost results in optimized solutions which only consider contacts longer than 15–20 minutes and closer than 2–3 meters to be at risk. Our results show that isolation and tracing can help control re-emerging outbreaks when some conditions are met: (i) a reduction of the reproductive number through masks and physical distance; (ii) a low-delay isolation of infected individuals; (iii) a high compliance. Finally, we observe the inefficacy of a less privacy-preserving tracing involving second order contacts. Our results may inform digital contact tracing efforts currently being implemented across several countries worldwide.

Inter-Ethnic Dynamics in the Wake of Terrorist Attacks: Evidence from the 2015 Baga Massacre

2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Alessandro Belmonte
Keyword(s):  
Ethnic Groups ◽  
Large Scale ◽  
Natural Experiment ◽  
Individual Characteristics ◽  
The State ◽  
Terrorist Attacks ◽  
Boko Haram ◽  
Far North ◽  
North East

AbstractThis paper investigates the consequences for inter-group conflicts of terrorist attacks. I study the 2015 Baga massacre, a large scale attack conducted by Boko Haram at the far North-East state of Borno, Nigeria, as a quasi-natural experiment and examine a set of attitudes in the aftermath of the event of Christians and Muslims throughout the country. Comparing individuals, outside the region of Borno, interviewed by Afrobarometer immediately after the massacre and those interviewed the days before within same regions and holding fixed a number of individual characteristics, I document that the informational exposure to the event rendered Christians less amiable to neighboring Muslims and Muslims less likely to recognize the legitimacy of the state. Nonetheless, Muslims increased their view of the elections as a device to remove leaders in office, event that took place 2 months later with the election of the challenger, Muhammadu Buhari. My findings indicate that terrorist attacks may generate a relevant and heterogeneous backlash across ethnic groups.

scholarly journals Malnutrition and morbidity trends in Somalia between 2007 and 2016: results from 291 cross-sectional surveys

BMJ Open ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. e033148
Author(s):  
Rocio Martin-Canavate ◽  
Estefania Custodio ◽  
Abukar Yusuf ◽  
Daniel Molla ◽  
Dominique Fasbender ◽  
...  
Keyword(s):  
Age Groups ◽  
Disease Outbreaks ◽  
Geographic Area ◽  
Complex Situation ◽  
Cross Sectional ◽  
Internally Displaced ◽  
North East ◽  
Continuous Complex ◽  
Morbidity Trends ◽  
Livelihood System

BackgroundMore than two decades of conflict and natural disasters in Somalia have resulted in one of the longest running humanitarian crises in the world. Nutrition data have been collected over the years despite challenges to inform programmatic action. This paper explores malnutrition and morbidity trends in Somalia during the last decade, disaggregated by geographical zone and livelihood system.MethodsWe used data from 291 cross-sectional surveys conducted in children aged 6–59 months between 2007 and 2016 in Somalia. Wasting, morbidity and stunting prevalences over time were analysed by geographic area, livelihood system and season. Logistic regressions were used to test trends.ResultsThe wasting trends show a striking peak in 2011, more marked in southern and central Somalia and coinciding with the famine declaration. The trend declines slightly thereafter although not consistently across all zones and livelihoods, and it raises again in 2016 especially among internally displaced persons (IDPs). Stunting declined for all groups and in all zones but with more consistent patterns in northern Somalia.Morbidity also showed a declining trend, although with multiple peaks depicting disease outbreaks.Pastoralist showed the lowest stunting estimates overall, while agrarian populations showed the lowest prevalence of wasting and morbidity. IDPs were the most affected by all outcomes. Seasonality affected the three outcomes differently by livelihood system. Stunting rates increased after the 2011 famine for all age groups within children under 5 years.ConclusionsDespite the continuous complex situation in Somalia, there has been a sustained decline in stunting and morbidity in the last decade. Wasting trends have remained at very high levels especially in north-east and the south zones of Somalia. The findings support the importance of performing trend analyses disaggregated by zone and livelihood groups within countries to better identify priorities for programme intervention.

Assessment of the feasibility of floodwater utilization in North-East China

Water Policy ◽  
2016 ◽  
Vol 18 (4) ◽  
pp. 862-876
Author(s):  
Jianwei Liu ◽  
Limin Kou ◽  
Qiang Zhou
Keyword(s):  
Large Scale ◽  
Local Conditions ◽  
North East ◽  
Management Measures ◽  
Main River ◽  
Monthly Runoff ◽  
Floodwater Utilization ◽  
Flood Resource Utilization ◽  
Storage Characteristics ◽  
Utilization Strategy

In order to alleviate the water supply–demand problem, a flood resource utilization strategy is proposed, called ‘Flood Utilization’. The strategy focuses on building large-scale water conservancy facilities and improving management measures. This paper presents the probability analysis of floodwater utilization in a confluence area, where a tributary joins a main river. Baicheng is used as the study area, where the Taoer River joins the Nenjiang River. After a large number of analyses, the main results and conclusions are as follows: First, the upper limit of available floodwater corresponds to the Taoer River's flood with a 5% probability of occurrence. Secondly, there are compensation characteristics between the two rivers which mean that the Nenjiang River can supply water to the Taoer River area. The analysis of monthly runoff, shows that there are compensation characteristics in 50.9% of the data period. The compensation rates (CRs) for the months from June to October are 0.2, 0.27, 0.25, 0.27, and 0.2, respectively. Thirdly, the differences in the runoff characteristics show that it is suitable for floodwater utilization. Finally, it is proposed that floodwater utilization measures are based on local conditions, such as the regional water storage characteristics and the runoff characteristics of the two rivers, and should be applied for different periods.

Global Reaction Model to Describe the Kinetics of Catalytic Pyrolysis of Coffee Grounds Waste

2017 ◽  
Vol 899 ◽  
pp. 173-178 ◽  
Author(s):  
Ronydes Batista Jr. ◽  
Bruna Sene Alves Araújo ◽  
Pedro Ivo Brandão e Melo Franco ◽  
Beatriz Cristina Silvério ◽  
Sandra Cristina Danta ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Large Scale ◽  
Catalytic Pyrolysis ◽  
Petroleum Products ◽  
Reaction Model ◽  
Heating Rates ◽  
Coffee Grounds ◽  
One Step ◽  
Global Reaction ◽  
The One

In view of the constant search for new sources of renewable energy, the particulate agro-industrial waste reuse emerges as an advantageous alternative. However, despite the advantages of using the biomass as an energy source, there is still strong resistance as the large-scale replacement of petroleum products due to the lack of scientifically proven efficient conversion technologies. In this context, the pyrolysis is presented as one of the most widely used thermal decomposition processes. The knowledge of aspects of chemical kinetics, thermodynamics these will, heat and mass transfer, are so important, since influence the quality of the product. This paper presents a kinetic study of slow pyrolysis of coffee grounds waste from dynamic thermogravimetric experiments (TG), using different powder catalysts. The primary thermal decomposition was described by the one-step reaction model, which considers a single global reaction. The kinetic parameters were estimated using nonlinear regression and the differential evolution method. The coffee ground waste was dried at 105°C for 24 hours. The sample in nature was analyzed at different heating rates, being 10, 15, 20, 30 and 50 K/min. In the catalytic pyrolysis, about 5% (w/w) of catalyst were added to the sample, at a heating rate of 30 K/min. The results show that the one-step model does not accurately represent the data of weight loss (TG) and its derivative (DTG), but can do an estimative of the activation energy reaction, and can show the differences caused by the catalysts. Although no one can say anything about the products formed with the addition of the catalyst, it would be necessary to micro-pyrolysis analysis, we can say the influence of the catalyst in the samples, based on the data obtained in thermogravimetric tests.

scholarly journals Large-Scale Atmospheric Dispersal Simulations Identify Likely Airborne Incursion Routes of Wheat Stem Rust Into Ethiopia

2017 ◽  
Vol 107 (10) ◽  
pp. 1175-1186 ◽  
Author(s):  
M. Meyer ◽  
L. Burgin ◽  
M. C. Hort ◽  
D. P. Hodson ◽  
C. A. Gilligan
Keyword(s):  
Stem Rust ◽  
Large Scale ◽  
Dispersion Model ◽  
Fungal Spores ◽  
Disease Outbreaks ◽  
Particle Dispersion ◽  
East African ◽  
Wheat Stem Rust ◽  
Sub Saharan ◽  
African Rift

In recent years, severe wheat stem rust epidemics hit Ethiopia, sub-Saharan Africa’s largest wheat-producing country. These were caused by race TKTTF (Digalu race) of the pathogen Puccinia graminis f. sp. tritici, which, in Ethiopia, was first detected at the beginning of August 2012. We use the incursion of this new pathogen race as a case study to determine likely airborne origins of fungal spores on regional and continental scales by means of a Lagrangian particle dispersion model (LPDM). Two different techniques, LPDM simulations forward and backward in time, are compared. The effects of release altitudes in time-backward simulations and P. graminis f. sp. tritici urediniospore viability functions in time-forward simulations are analyzed. Results suggest Yemen as the most likely origin but, also, point to other possible sources in the Middle East and the East African Rift Valley. This is plausible in light of available field surveys and phylogenetic data on TKTTF isolates from Ethiopia and other countries. Independent of the case involving TKTTF, we assess long-term dispersal trends (>10 years) to obtain quantitative estimates of the risk of exotic P. graminis f. sp. tritici spore transport (of any race) into Ethiopia for different ‘what-if’ scenarios of disease outbreaks in potential source countries in different months of the wheat season.

scholarly journals Employing Geographical Principles for Sampling in State of the Art Dialectological Projects

2013 ◽  
Vol 1 (2) ◽  
pp. 96-114 ◽  
Author(s):  
Isabelle Buchstaller ◽  
Seraphim Alvanides
Keyword(s):  
Large Scale ◽  
State Of The Art ◽  
Pilot Project ◽  
Linguistic Analysis ◽  
Human Geography ◽  
North East ◽  
The North ◽  
Functional Regions ◽  
Demographic Classification

The aims of this paper are twofold. First, we locate the most effective human geographical methods for sampling across space in large-scale dialectological projects. We propose two geographical concepts as a basis for sampling decisions: Geo-demographic classification, which is a multidimensional method used for the socio-economic grouping of areas; we also develop an updated version of functional regions that can be used in sociolinguistic research. We then report on the results of a pilot project that applies these models to collect data regarding the acceptability of vernacular morphosyntactic forms in the North East of England. Following the method of natural breaks advocated for dialectology by Horvath & Horvath (2002), we interpret breaks in the probabilistic patterns as areas of dialect transitions. This study contributes to the debate about the role and limitations of spatiality in linguistic analysis. It intends to broaden our knowledge about the interfaces between human geography and dialectology.

scholarly journals Information Communication Technologies (ICTs), Crisis Communication Principles and the COVID-19 Response in South Korea

2021 ◽  
pp. 097325862098117
Author(s):  
Hye-Jin Paek ◽  
Thomas Hove
Keyword(s):  
Crisis Communication ◽  
Large Scale ◽  
Communication Strategies ◽  
Disease Outbreaks ◽  
Information Communication ◽  
Information And Communications Technologies ◽  
The South ◽  
South Korean ◽  
Infectious Disease Outbreaks ◽  
Control Programmes

This case study highlights several communication insights that have emerged from the South Korean national response to COVID-19. In particular, it focuses on how innovative disease control programmes and information and communications technologies (ICT) have been used in conjunction with appropriate message strategies. The South Korean government used ICTs in a variety of ways to enhance crisis communication, coordinate large-scale public health efforts and supply chains, and facilitate widespread adoption of preventive measures such as social distancing and mask wearing. The response and communication strategies were based on principles established by research in social sciences and recommended for pandemic response, including social marketing, crisis communication, and normative influence. South Korea’s COVID-19 response and communication strategies can provide useful insights for national efforts to manage COVID-19 and other possible future infectious disease outbreaks.

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