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Kelly, S. A.

Publications and source records attributed to Kelly, S. A..

4 recordsLinked to original sources

Prediction of mosquito vector abundance for threespecies in the Anopheles gambiae complex

BackgroundThe dynamics of vector borne disease transmission depend on the abundances of vectors. The dominant malaria vector species complex of Anopheles gambiae sensu lato is a target of vector control strategies designed to reduce and eliminate malaria transmission. The three most widely distributed dominant malaria vectors within the species complex are An. arabiensis, An. coluzzii and An. gambiae sensu stricto. MethodsPrevious studies across the extent of the species complex range have been restricted to annual predictions of species occurrence or relative abundance. This study incorporated relative abundance data at the species level and abundance data at the species complex level to estimate and predict daily equilibrium vector abundances of each species. Statistical models with interpretable parameters were used to gain insight into how factors such as meteorological conditions, insecticide treated net use, and human density affect the spatial and temporal predictions. The statistical models were used to predict daily equilibrium vector abundance that is an important factor in indices of malaria transmission such as the basic reproduction number and vectorial capacity. ResultsMeteorological factors, such as precipitation and relative humidity, and human factors, such as population density and insecticide treated nets, were important predictors of these three malaria vector species in Africa. Insecticide treated net use was negatively associated with per capita vector abundance of the An. gambiae species complex and interacted with year to suggest an a negative effect on the ratio of An. gambiae s.s. to An. arabiensis at the end of the prediction period that extended from 2002 to 2020. A predicted increasing interannual trend for An. coluzzii was potentially caused by changing species identification methods. ConclusionThe predicted equilibrium abundances of the three species showed potentially high levels of geographical overlap, niche overlap, and evidence for stable coexistence despite substantial interspecific competition. Improving collection of longitudinal species abundance data across the spatial range of the An. gambiae species complex will facilitate future explorations of causal hypotheses that relate vector abundance to control measures, malaria interventions and meteorological conditions.

ecology↗

Polyolefin colonization and partial degradation by Gordonia sp., and Arthrobacter sp. isolated from wetlands and compost

Plastics and microplastics constitute an ever-increasing pollutant in the biosphere. There is clear evidence that environmental microbes possess enzyme systems and metabolic apparatus to degrade natural high molecular weight polymers, which substantially overlap with those involved in the biodegradation of plastics. This study investigated the presence and activities of plastic-degrading microbes in environments with a high abundance of plant-derived polymers, including cellulosic, chitinous, or lignin-derived compounds. Microbes were enriched in a minimal medium, with low-density polyethylene (LDPE), polypropylene (PP), poly(ethylene terephthalate) (PET), or polystyrene (PS) as the sole carbon source, resulting in 12 bacterial isolates. Plastic mass loss and cell viability were measured over a 28-day incubation period, in addition to assessment of biofilm formation. Gordonia sp. iso11 displayed mass loss of PP of up to 22.8% and formed a viable dense biofilm (109 CFU cm-2) on a PP film. A putative alkane-1-monoxygenase (AlkB) was identified from genome sequence analysis, which aligned with a known LDPE-degrading enzyme. Furthermore, reductions in the contact angle of medium supernatant from Gordonia sp. iso11 provided evidence of biosurfactant production which may enhance the bioavailability of the synthetic plastic. To our knowledge, this is the first demonstration of PP degradation by Gordonia.

microbiology↗

It All Rolls Downstream: Upstream Control of Physical Activity Regulation

Physical activity is regulated by a variety of genetic molecules. However, the pathways through which those molecules work to regulate activity is largely unknown. The purpose of this study was to gather the known genetic molecules that are associated with activity regulation and define overall upstream regulator pathways through which these molecules work. We conducted a systematic review to gather all available published datasets related to physical activity regulation, standardized the data for genomic location and species, and used this data, in an unbiased manner to create a dataset that was used: (1) to physically map and visualize all identified molecules to homologous chromosome locations and (2) as the dataset for which an Upstream Regulator Analysis (URA) was conducted using Qiagen Ingenuity Pathway Analysis (IPA) software. Our search resulted in 469 genetic molecules (e.g. genomic variant, transcript, protein, micro-RNA) that were split into brain (n=366) and muscle (n=345) sub-groups, which was our attempt to separate differences in central vs peripheral pathways. The brain and muscle data sets had several potential upstream regulators, the top-rated being {beta}-estradiol as a regulator for 19.5% and 21% of the brain and muscle datasets respectively. To our knowledge, {beta}-estradiols identification as a potential regulator, is the first evidence to link the well-known effects of sex hormones on physical activity with genetic regulation of physical activity. There were a variety of potential upstream regulators for the molecules collected in this review, but interestingly, three of the top five for both brain and muscle are nuclear receptor binding ligands; estradiol (estrogen receptor), dexamethasone (glucocorticoid receptor), and tretinoin (retinoic acid receptor), indicating a potential role of nuclear receptors in the regulation of physical activity. Selective nuclear receptor modulation may be an area of interest in future mechanistic studies of the genetic regulation of physical activity.

genetics↗

Minimum Information for Reusable Arthropod Abundance Data (MIReAAD)

Introduction Introduction Discussion Conclusion References Arthropods play a dominant role in the dynamics of practically all natural and human-modified terrestrial ecosystems1-3, and have significant economic and health effects. For example, certain insects provide significant economic benefits (e.g. pollination) exceeding $57 billion a year to the United States alone4. Meanwhile, invasive insects cost an estimated $70 billion dollars per year globally5 and insect pests may reduce agricultural harvests by up to 16%, with an equal amount of further losses of harvested goods6. Particularly noteworthy is a subset of arthropods that are disease vectors, transmitting pathogens to and between animals as well as plan ...

ecology↗