565 research outputs found
Documenting museum records of west African Coccinellidae (Coleoptera) in Benin and Senegal
Open Access JournalThis work provides a preliminary inventory of West African Coccinellidae.
This was based on the West African Coccinellidae (WAC) specimens in the holdings of insect collections at the Laboratoire de Zoologie des Invertébrés Terrestres at the Institut Fondamental d’Afrique Noire Cheikh Anta Diop (IFAN), Senegal and the Biodiversity Center at the International Institute of Tropical Agriculture (IITAB), Benin
DNA Barcoding to Improve the Taxonomy of the Afrotropical Hoverflies (Insecta: Diptera: Syrphidae)
The identification of Afrotropical hoverflies is very difficult because of limited recent taxonomic revisions and the lack of comprehensive identification keys. In order to assist in their identification, and to improve the taxonomy of this group, we constructed a reference dataset of 513 COI barcodes of 90 of the more common nominal species from Ghana, Togo, Benin and Nigeria (W Africa) and added ten publically available COI barcodes from nine nominal Afrotropical species to this (total: 523 COI barcodes; 98 nominal species; 26 genera). The identification accuracy of this dataset was evaluated with three methods (K2P distance-based, Neighbor-Joining (NJ) / Maximum Likelihood (ML) analysis, and using SpeciesIdentifier). Results of the three methods were highly congruent and showed a high identification success. Nine species pairs showed a low ( 0.03) maximum intraspecific K2P distance was observed in eight species and barcodes of these species not always formed single clusters in the NJ / ML analayses which may indicate the occurrence of cryptic species. Optimal K2P thresholds to differentiate intra- from interspecific K2P divergence were highly different among the three subfamilies (Eristalinae: 0.037, Syrphinae: 0.06, Microdontinae: 0.007–0.02), and among the different general suggesting that optimal thresholds are better defined at the genus level. In addition to providing an alternative identification tool, our study indicates that DNA barcoding improves the taxonomy of Afrotropical hoverflies by selecting (groups of) taxa that deserve further taxonomic study, and by attributing the unknown sex to species for which only one of the sexes is known
Implementation and scaling of the fully coupled Terrestrial Systems Modeling Platform (TerrSysMP) in a massively parallel supercomputing environment – a case study on JUQUEEN (IBM Blue Gene/Q)
Continental-scale hyper-resolution simulations constitute a grand challenge in characterizing non-linear feedbacks of states and fluxes of the coupled water, energy, and biogeochemical cycles of terrestrial systems. Tackling this challenge requires advanced coupling and supercomputing technologies for earth system models that are discussed in this study, utilizing the example of the implementation of the newly developed Terrestrial Systems Modeling Platform (TerrSysMP) on JUQUEEN (IBM Blue Gene/Q) of the Jülich Supercomputing Centre, Germany. The applied coupling strategies rely on the Multiple Program Multiple Data (MPMD) paradigm and require memory and load balancing considerations in the exchange of the coupling fields between different component models and allocation of computational resources, respectively. These considerations can be reached with advanced profiling and tracing tools leading to the efficient use of massively parallel computing environments, which is then mainly determined by the parallel performance of individual component models. However, the problem of model I/O and initialization in the peta-scale range requires major attention, because this constitutes a true big data challenge in the perspective of future exa-scale capabilities, which is unsolved
Taxonomic revision of the Afrotropical hover fly genus Senaspis Macquart (Diptera, Syrphidae)
Open Access Article; Published online: 14 Dec 2020The representatives of the Afrotropical hover fly genus Senaspis Macquart (Diptera) are revised. In total, ten species are recognized. Senaspis apophysata (Bezzi) is herewith placed as junior synonym of S. flaviceps Macquart, S. livida (Bezzi) is herewith placed as junior synonym of S. dentipes (Macquart) and S. griseifacies (Bezzi) is herewith placed as junior synonym of S. haemorrhoa (Gerstaecker). All species are redescribed and an identification key is provided. DNA barcoding analysis (7 species, 64 barcodes) showed that the technique can be used to unambiguously identify the species. The relationships among the different Senaspis species are discussed based on morphological and DNA data
Taxonomic revision of the afrotropical Phytomia gerin-meneville (Diptera: syrphidae)
Open Access Article; Published online: 26 Jun 2020The Afrotropical representatives of the hoverfly genus Phytomia Guérin-Méneville (Diptera) are revised. In total, 19 species are recognized of which three are new to science: Phytomia austeni sp. nov., P. memnon sp. nov., and P. pallida sp. nov. Phytomia neavei Bezzi is considered a junior synonym of P. kroeberi (Bezzi), P. noctilio Speiser a junior synonym of P. pubipennis Bezzi, and P. ephippium Bezzi a junior synonym of P. melas (Bezzi). Lectotypes are designated for the following species: Megaspis bulligera Austen, Megaspis erratica Bezzi, and Megaspis poensis Bezzi. In addition, unpublished lectotype designations are hereby formally published for the following species: Megaspis bullata Loew, Megaspis curta Loew, and Megaspis capito Loew. Phytomia curta (Loew) is considered a valid species, and differentiated from P. natalensis (Macquart). Phytomia fronto Loew is tentatively considered to belong to the genus Simoides Loew. The relationship between the different Phytomia species, as well as the relationship between Phytomia and Simoides, is briefly discussed based on morphological and DNA data
Notes on the Afrotropical hover fly genus Meromacroides Curran (Syrphidae, Eristalinae)
The African endemic hover fly Meromacroides meromacriformis (Bezzi, 1915) (Syrphidae, Eristalinae) was
described more than a century ago and its monotypic status established in 1927, but subsequent collections and publications are rare. Only the male has been described and nothing is known about its biology. We re-describe the male, including geographic variation, describe the female for the first time and
provide the first DNA barcodes for the species. Despite the large range and observed variations, there is
insufficient evidence to describe additional taxa in the genus. Biological observations are presented, which
may shed some insight into this rare and enigmatic hover fly, whose known distribution now spans the
Afrotropical Region
Impact of groundwater representation on heat events in regional climate simulations over Europe
The representation of groundwater is simplified in most regional climate models (RCMs), potentially leading to biases in the simulations. This study introduces a unique dataset from the regional Terrestrial Systems Modelling Platform (TSMP) driven by the Max Planck Institute Earth System Model at Low Resolution (MPI-ESM-LR) boundary conditions in the context of dynamical downscaling of global climate models (GCMs) for climate change studies. TSMP explicitly simulates full 3D soil and groundwater dynamics together with overland flow, including complete water and energy cycles from the bedrock to the top of the atmosphere. By comparing the statistics of heat events, i.e., a series of consecutive days with a near-surface temperature exceeding the 90th percentile of the reference period, from TSMP and those from GCM–RCM simulations with simplified groundwater dynamics from the COordinated Regional Climate Downscaling EXperiment (CORDEX) for the European domain, we aim to improve the understanding of how groundwater representation affects heat events in Europe.
The analysis was carried out using RCM outputs for the summer seasons of 1976–2005 relative to the reference period of 1961–1990. While our results show that TSMP simulates heat events consistently with the CORDEX ensemble, there are some systematic differences that we attribute to the more realistic representation of groundwater in TSMP. Compared to the CORDEX ensemble, TSMP simulates fewer hot days (i.e., days with a near-surface temperature exceeding the 90th percentile of the reference period) and lower interannual variability and decadal change in the number of hot days on average over Europe. TSMP systematically simulates fewer heat waves (i.e., heat events lasting 6 d or more) compared to the CORDEX ensemble; moreover, they are shorter and less intense. The Iberian Peninsula is particularly sensitive with respect to groundwater. Therefore, incorporating an explicit 3D groundwater representation in RCMs may be a key in reducing biases in simulated duration, intensity, and frequency of heat waves in Europe. The results highlight the importance of hydrological processes for the long-term regional climate simulations and provide indications of possible potential implications for climate change projections.</p
The fall armyworm strain associated with most rice, millet, and pasture infestations in the Western Hemisphere is rare or absent in Ghana and Togo
Open Access Journal; Published online: 21 June 2021The moth pest fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is now present throughout much of the Eastern Hemisphere where it poses a significant economic threat to a number of crops. Native to the Western Hemisphere, fall armyworm is one of the primary pests of corn in the Americas and periodically causes significant economic damage to sorghum, millet, cotton, rice, and forage grasses. This broad host range is in part the result of two populations historically designated as host strains (C-strain and R-strain) that differ in their host plant preferences. Reports of infestations in Africa have to date mostly been limited to the C-strain preferred crops of corn and sorghum, with little evidence of an R-strain presence. However, this could reflect a bias in monitoring intensity, with the R-strain perhaps being more prevalent in other crop systems that have not been as routinely examined for the pest. Because knowledge of whether and to what extent both strains are present is critical to assessments of crops at immediate risk, we analyzed specimens obtained from a systematic survey of pasture grass and rice fields, habitats typically preferred by the R-strain, done contemporaneously with collections from corn fields in Ghana and Togo. Substantial larval infestations were only observed in corn, while pheromone trap capture numbers were high only in corn and rice habitats. Little to no fall armyworm were found in the pasture setting. Comparisons with a meta-analysis of studies from South America identified differences in the pattern of strain-specific markers typically found in fall armyworm collected from rice habitats between the two hemispheres. Genetic tests of specimens from rice and corn area traps failed to show evidence of differential mating between strains. These results are consistent with the R-strain being rare or even absent in Africa and, at least for the Ghana-Togo area, this R-strain lack does not appear to be due to limitations in pest monitoring. The implications of these results to the crops at risk in Africa and the accuracy of existing molecular markers of strain identity are discussed
Some biological parameters of Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae) and its natural enemy Acerophagus papayae Noyes et Schauff (Hymenoptera: Encyrtidae)
The papaya mealybug Paracoccus marginatus Williams and Granara De Willink (Hemiptera: Pseudococcidae) is an invasive insect species attacking diverse host plants causing enormous damage to crops including those of very high economic importance. Biological control of this mealybug is achieved through the field release of its natural enemy, Acerophagus papayae Noyes and Schauff (Hymenoptera: Encyrtidae). The study aims to determine the developmental time and mortality rate of the different stages of P. marginatus; daily fecundity and pre- oviposition, oviposition and post-oviposition times of a female P. marginatus and the total average number of emerging individuals of the hosts parasitized in 24 hours by a female and the total average development time of A. papayae.
This study, which was conducted in the laboratory under conditions of 28 ± 2°C, 75 ± 5% RH, 12: 12 LD, determined the average daily fecundity of a female P. marginatus and the average number of offspring of a female A. papayae per day. The results obtained showed that a female P. marginatus has three periods of reproductive activity, namely the pre-oviposition, oviposition and post-oviposition periods, which are on average last 7.74 ± 1.26, 6.13 ± 3.02 and 7.45 ± 4.27 days respectively. During oviposition, a female P. marginatus lays an average of 25.262 ± 11.16 eggs per day, and an average total of 224.32 ± 29.99 eggs during her lifetime, which averages 18.44 ± 3.31 days. Also, during the development of the pre-imaginal stages of P. marginatus, significant mortality rates were noted in the first and second larval stages, which are 61.40 ± 0.05 and 52.8 ± 0.025 respectively, whereas in the third stage, this rate is 35.02 ± 0.03 for the female and zero for the male. The average total development time of the pest was 25.98 ± 4.47 days for the female and 29.70 ± 5.58 days for the male. In contrast, the progeny of its natural enemy A. papayae averaged 8.22 ± 4.676 males and 10.53 ± 4.43 females per day, giving an average total of 18.75 ± 9.087 offspring per day. During its lifetime (13.02 ± 0.08 days), a female A. papayae produced an average of 205.96 ± 9.87 offspring in an average development time of 13.82 ± 0.013 days. These results obtained on the progeny of a female and the development time of A. papayae species in relation to that of its host can be used to evaluate the effectiveness of the parasitoid in the management of the pest populations in Togo
Economic evaluation of a clinical protocol for diagnosing emergency patients with suspected pulmonary embolism
BACKGROUND: The objective of this paper is to estimate the amount of cost-savings to the Australian health care system from implementing an evidence-based clinical protocol for diagnosing emergency patients with suspected pulmonary embolism (PE) at the Emergency department of a Victorian public hospital with 50,000 presentations in 2001–2002. METHODS: A cost-minimisation study used the data collected in a controlled clinical trial of a clinical protocol for diagnosing patients with suspected PE. Thenumber and type of diagnostic tests in a historic cohort of 185 randomly selected patients, who presented to the emergency department with suspectedPE during an eight month period prior to the clinical trial (January 2002 -August 2002) were compared with the number and type of diagnostic tests in745 patients, who presented to the emergency department with suspected PE from November 2002 to August 2003. Current Medicare fees per test were usedas unit costs to calculate the mean aggregated cost of diagnostic investigation per patient in both study groups. A t-test was used to estimate the statistical significance of the difference in the cost of resources used for diagnosing PE in the control and in the intervention group. RESULTS: The trial demonstrated that diagnosing PE using an evidence-based clinical protocol was as effective as the existing clinical practice. The clinical protocol offers the advantage of reducing the use of diagnostic imaging, resulting in an average cost savings of at least 59.30 per patient to the wholeof Australia could potentially result in annual savings between 3.7 million
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