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Item Hot days are associated with short-term adrenocortical responses in a southern African arid-zone passerine bird.(The Company of Biologists, 2021-03-09) Moagi, Lesedi L.; Bourne, Amanda R.; Cunningham, Susan J.; Jansen, Raymond; Ngcamphalala, Celiwe A.; Ganswindt, André; Ridley, Amanda R.; McKechnie, Andrew E.Relatively little effort has been directed towards elucidating the role of physiological stress pathways in mediating avian responses to global heating. For free-ranging southern pied babblers, Turdoides bicolor, daily maximum air temperatures (Tmax) between ∼35 and ∼40°C result in reduced foraging efficiency, loss of body mass and compromised breeding success. We tested the hypothesis that very hot days are experienced as stressors by quantifying relationships between Tmax and faecal glucocorticoid metabolite (fGCM) levels in naturally excreted droppings. On days when Tmax<38°C, fGCM levels were independent of Tmax (mean±s.d. 140.25±56.92 ng g−1 dry mass). At Tmax>38°C, however, fGCM levels increased linearly with Tmax and averaged 190.79±70.13 ng g−1 dry mass. The effects of Tmax on fGCM levels did not carry over to the following morning, suggesting that very hot days are experienced as acute stressors.Item Gastrointestinal nematodes in two galliform birds from South Africa: Patterns associated with host sex and age.(Springer, 2021-06-16) Junker, Kerstin; Spickett, Andrea; Davies, Owen R.; Jansen, Raymond; Krasnov, Boris R.Parasite ecology has recently focused on elucidating patterns and processes that shape helminth communities in avian hosts. However, helminths parasitizing gamebirds are still poorly understood. Here we describe the gastrointestinal nematode fauna of Swainson’s spurfowl, Pternistis swainsonii (Phasianidae) and helmeted guineafowl, Numida meleagris (Numididae), collected at three and four localities, respectively, in South Africa and analyze the prevalence, mean abundance and diversity of their helminth communities. Eleven nematode species were collected from spurfowl, which had a mean number of nematode species per host of 3.01 ± 0.18, whereas guineafowl harboured 15 nematode species, with a mean number of nematode species per host of 3.93 ± 0.12. Focusing on the most prevalent species, we also asked if host sex and/or age were associated with infracommunity structure with regard to nematode counts and species richness, as well as the species and taxonomic composition of infracommunities. While pooling data of nematode species masked the influence of host characteristics on helminth communities, analysis of individual nematode species revealed a number of patterns. In particular, adult female bias was seen in Tetrameres swainsonii in spurfowl and in Allodapa dentigera and Gongylonema congolense in guineafowl; Acuaria gruveli reached higher numbers in adult spurfowl than in juveniles, and helminth infra communities in juvenile male guineafowl were more species rich than those in adult males. Combined, our results suggest that helminth communities of spurfowl and guineafowl are associated with a complex interplay of numerous factors, including host characteristics, parasite traits and environmental conditions.Item Guidance for first responders on the short-term care of confiscated pangolins.(IUCN SSC Pangolin Specialist Group, 2021-12-01) Jansen, Ray; Willis, Jasmin; Waterman, Carly; Challender, DanThis primarily occurs within Asia and Africa, and from Africa to Asia2, but also involves Europe, North America, and other parts of the world. Trade can involve live and dead pangolins, their scales, and other body parts (e.g., skins). Live pangolins are commonly confiscated by local, regional or national law enforcement authorities in Asia and Africa, and many are in ill health because of poor treatment in the illegal trade3. Trafficking takes place despite legislation prohibiting the harvest of pangolins in most countries where pangolins are found and a ban on the commercial, international trade in wild-caught pangolins, which applies to all eight species. Part 1 of this guide is for first responders to instances of trafficking involving live pangolins, including police and customs officers, and other law enforcement agents.Item A global review identifies agriculture as the main threat to declining grassland birds.(Wiley, 2023-05-09) Douglas, David J.T.; Waldinger, Jessica; Buckmire, Zoya; Gibb, Kathryn; Medina, Juan P.; Sutcliffe, Lee; Beckmann, Christa; Collar, Nigel J.; Jansen, Raymond; Kamp, Johannes; Little, Ian; Sheldon, Rob; Yanosky, Alberto; Koper, NicolaGrasslands are globally threatened and their biodiversity, including grassland birds, is declining markedly. To inform grassland bird conservation globally, we systematically reviewed threats and conservation actions for grassland birds, extracting data from 528 papers. Across the 10 primary grassland regions of the globe, agriculture was the most frequently or joint most frequently reported threat in nine regions (reported as a threat in 73% of publications); hunting was the most frequently reported threat in the remaining region. Natural system modifications (reported as a threat in 32% of publications) and climate change and severe weather (24%) were less frequently reported threats compared with agriculture. The types of threat from agriculture varied regionally, but the most pervasive were livestock farming and ranching (reported in 58% of publications where agriculture was a primary threat) and non-timber cropping (43%). Most agricultural threats relate to intensification, but agricultural abandonment, typically the cessation of grazing, sometimes accompanied by tree planting/succession, poses an emerging threat to some grassland birds (reported in 32% of publications where agriculture was a primary threat). The most frequent conservation actions implemented to date include land/water management and protection, and species-specific management actions. Authors of reviewed publications in almost all regions recommend more land/water management, followed by calls for further land/water protection. The parlous state of grassland birds globally suggests that existing conservation actions for grasslands are inadequate. Furthermore, our review suggests that these should be primarily targeted at reversing the negative impacts of agriculture, in particular livestock farming and cropping.Item Polymeric nanocomposite materials for photocatalytic detoxification of polycyclic aromatic hydrocarbons in aquatic environments-A review.(Elsevier B.V., 2022-07-01) Munyengabe, Alexis; Ndibewu, Peter Papoh; Sibali, Linda Lunga; Ngobeni, PrincePolycyclic aromatic hydrocarbons (PAHs) are a known class of persistent and ubiquitous contaminants not only found in sediments but also associated with coastal areas and waters of urbanized estuaries. Due to their hydrophobic nature, PAHs tend to accumulate in the aquatic sediments, leading to bioaccumulation and elevated concentrations over time which is of global concern owing to the serious health risks that they pose to both humans and aquatic life. However, this review highlights various polymeric nanocomposite materials (PNMs) used for the photocatalytic degradation and mechanism of PAHs in aquatic sediments and associated water bodies. It presents the current progress made in the understanding of the toxicological effects of PAHs and mechanisms of their detoxification using photocatalytic processes as an alternative green method for environmental pollution, remediation and control. The paper also provides a brief account of the chemistry, origin and photocatalytic transformation of PAHs, highlighting their bioaccumulation in aquatic sediments and marine environments. It finally accentuates the significance of PNMs as a plausible candidate for the effective treatment of PAHs-contaminated aquatic environments. The available literature reveals that a small number of PNMs has been used to photodegrade PAHs in industrial effluents, seawater, aqueous solution and synthetic wastewater samples. Anthracene, phenanthrene, 2-naphthol and naphthalene as low molecular weight -PAHs were photodegraded using these PNMs under natural light. The findings also show that only chitosan- and graphene oxide based PNMs have been employed to photodegrade these kinds of PAHs in water matrices. Most of the PNMs found in the literature were based on the iron oxide or magnetite incorporation which generates reactive oxygen species via AOPs. Another finding was no study was conducted on the photodegradation of PAHs in soil and sediments which are their main sink in the environment.Item The effect of air supply on nitrogen removal using a biological filter proposed for ventilated pit latrines.(2011-04-21) Coetzee, Martha A.A.; Roux-Van der Merwe, Magaretha P.; Badenhorst, JacquelinePit latrines are the most commonly used sanitation systems in many developing countries. Various researchers have reported elevated nitrate concentrations in groundwater in the vicinity of pit latrines and this could pose a serious health risk to the users of the water source. Faecal sludge from pit latrines contains high concentrations of nitrogen and organic matter (3-5 g∙ℓ−1 N and 20-50 g∙ℓ−1 COD); however, it is produced at a very low rate (1.5 ℓ∙capita−1∙d−1) relative to that of waterborne sewage systems. A pit latrine basically only confines the waste, and no real treatment takes place. In this research the nitrogen was removed in a biological filter using a combination of nitrification and denitrification processes. The aim of this investigation was to determine the effect of air supplied at different rates, namely, 0, 0.3, 1.0 and 2.0 m3∙h−1 N, on the biological filtration process. The application rate was 0.04 m3∙m−2∙d−1. More than 90% removal of nitrogen was observed at an air supply rate of 1.0 m3∙h−1 N. At lower air supply rates nitrification was not complete. At an air supply rate of 2.0 m3∙h−1 nitrogen removal was also approx. 90%, but the biological filter only became stable after about 2 months of operation, possibly due to desiccation of the biomass.Item Physicochemical characterization of maize tassel as an adsorbent. I. Surface texture, microstructure, and thermal stability(Wiley InterScience, 2008-08-09) Zvinowanda, Caliphs M.; Okonkwo, Jonathan O.; Agyei, Nana M.; Shabalala, Pride N.In this study, various physicochemical parameters were evaluated for maize tassel, a novel adsorbent. The Brunauer–Emmett–Teller (BET) isotherm was used to experimentally model N2-adsorption data (up to a relative pressure of 0.30); the results indicated that the powdered material was mesoporous with a BET specific surface area, total volume (up to a relative pressure of 0.98), and average pore width (4V/A by BET) of 2.52 m2/g, 0.0045 cm3/g, and 7.2 nm, respectively, for the 150–300-lm fraction. Laser diffraction pattern analysis yielded particle size distributions for the 45–50-, 50–150-, and 150–300-lm fractions. High-resolution scanning electron microscopy revealed a microstructure showing predominantly flattish, rodlike particles. The material exhibited stability to thermal decomposition up to about 230C, as evidenced by the results obtained from simultaneous thermogravimetry/differential thermal analysis and differential scanning calorimetry.