Publications by authors named "Adam Yates"

43 Publications

The Biological Assessment and Rehabilitation of the World's Rivers: An Overview.

Water (Basel) 2021 Jan;13(3):371

Department of Geography, Western University and Canadian Rivers Institute, London, ON N6A 5C2, Canada.

The biological assessment of rivers i.e., their assessment through use of aquatic assemblages, integrates the effects of multiple-stressors on these systems over time and is essential to evaluate ecosystem condition and establish recovery measures. It has been undertaken in many countries since the 1990s, but not globally. And where national or multi-national monitoring networks have gathered large amounts of data, the poor water body classifications have not necessarily resulted in the rehabilitation of rivers. Thus, here we aimed to identify major gaps in the biological assessment and rehabilitation of rivers worldwide by focusing on the best examples in Asia, Europe, Oceania, and North, Central, and South America. Our study showed that it is not possible so far to draw a world map of the ecological quality of rivers. Biological assessment of rivers and streams is only implemented officially nation-wide and regularly in the European Union, Japan, Republic of Korea, South Africa, and the USA. In Australia, Canada, China, New Zealand, and Singapore it has been implemented officially at the state/province level (in some cases using common protocols) or in major catchments or even only once at the national level to define reference conditions (Australia). In other cases, biological monitoring is driven by a specific problem, impact assessments, water licenses, or the need to rehabilitate a river or a river section (as in Brazil, South Korea, China, Canada, Japan, Australia). In some countries monitoring programs have only been explored by research teams mostly at the catchment or local level (e.g., Brazil, Mexico, Chile, China, India, Malaysia, Thailand, Vietnam) or implemented by citizen science groups (e.g., Southern Africa, Gambia, East Africa, Australia, Brazil, Canada). The existing large-extent assessments show a striking loss of biodiversity in the last 2-3 decades in Japanese and New Zealand rivers (e.g., 42% and 70% of fish species threatened or endangered, respectively). A poor condition (below Good condition) exists in 25% of South Korean rivers, half of the European water bodies, and 44% of USA rivers, while in Australia 30% of the reaches sampled were significantly impaired in 2006. Regarding river rehabilitation, the greatest implementation has occurred in North America, Australia, Northern Europe, Japan, Singapore, and the Republic of Korea. Most rehabilitation measures have been related to improving water quality and river connectivity for fish or the improvement of riparian vegetation. The limited extent of most rehabilitation measures (i.e., not considering the entire catchment) often constrains the improvement of biological condition. Yet, many rehabilitation projects also lack pre-and/or post-monitoring of ecological condition, which prevents assessing the success and shortcomings of the recovery measures. Economic constraints are the most cited limitation for implementing monitoring programs and rehabilitation actions, followed by technical limitations, limited knowledge of the fauna and flora and their life-history traits (especially in Africa, South America and Mexico), and poor awareness by decision-makers. On the other hand, citizen involvement is recognized as key to the success and sustainability of rehabilitation projects. Thus, establishing rehabilitation needs, defining clear goals, tracking progress towards achieving them, and involving local populations and stakeholders are key recommendations for rehabilitation projects (Table 1). Large-extent and long-term monitoring programs are also essential to provide a realistic overview of the condition of rivers worldwide. Soon, the use of DNA biological samples and eDNA to investigate aquatic diversity could contribute to reducing costs and thus increase monitoring efforts and a more complete assessment of biodiversity. Finally, we propose developing transcontinental teams to elaborate and improve technical guidelines for implementing biological monitoring programs and river rehabilitation and establishing common financial and technical frameworks for managing international catchments. We also recommend providing such expert teams through the United Nations Environment Program to aid the extension of biomonitoring, bioassessment, and river rehabilitation knowledge globally.
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http://dx.doi.org/10.3390/w13030371DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8048141PMC
January 2021

Clinical laboratory reference values in adults in Kisumu County, Western Kenya; hematology, chemistry and CD4.

PLoS One 2021 30;16(3):e0249259. Epub 2021 Mar 30.

U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States of America.

Background: Clinical laboratory reference intervals (RIs) are essential for diagnosing and managing patients in routine clinical care as well as establishing eligibility criteria and defining adverse events in clinical trials, but may vary by age, gender, genetics, nutrition and geographic location. It is, therefore, critical to establish region-specific reference values in order to inform clinical decision-making.

Methods: We analyzed data from a prospective observational HIV incidence cohort study in Kombewa, Kenya. Study participants were healthy males and females, aged 18-35 years, without HIV. Median and 95% reference values (2.5th percentile to 97.5th percentile) were calculated for laboratory parameters including hematology, chemistry studies, and CD4 T cell count. Standard Deviation Ratios (SDR) and Bias Ratios (BR) are presented as measures of effect magnitude. Findings were compared with those from the United States and other Kenyan studies.

Results: A total of 299 participants were analyzed with a median age of 24 years (interquartile range: 21-28). Ratio of males to females was 0.9:1. Hemoglobin range (2.5th-97.5th percentiles) was 12.0-17.9 g/dL and 9.5-15.3 g/dL in men and women respectively. In the cohort, MCV range was 59-95fL, WBC 3.7-9.2×103/μL, and platelet 154-401×103/μL. Chemistry values were higher in males; the creatinine RI was 59-103 μmol/L in males vs. 46-76 μmol/L in females (BRUL>.3); and the alanine transferase range was 8.8-45.3 U/L in males vs. 7.5-36.8 U/L in females (SDR>.3). The overall CD4 T cell count RI was 491-1381 cells/μL. Some parameters including hemoglobin, neutrophil, creatinine and ALT varied with that from prior studies in Kenya and the US.

Conclusion: This study not only provides clinical reference intervals for a population in Kisumu County but also highlights the variations in comparable settings, accentuating the requirement for region-specific reference values to improve patient care, scientific validity, and quality of clinical trials in Africa.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0249259PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009432PMC
March 2021

Contribution of nitrogen sources to streams in mixed-use catchments varies seasonally in a cold temperate region.

Sci Total Environ 2021 Apr 7;764:142824. Epub 2020 Oct 7.

The University of Western Ontario and Canadian Rivers Institute, Department of Geography and Environment, 1151 Richmond Street, London, Ontario N6A 5C2, Canada.

Intensive agriculture and growing human populations are important nitrogen (N) sources thought to be associated with eutrophication. However, the contribution and seasonality of N delivery to streams from human activities is poorly understood and knowledge of the role of stream communities in the assimilation of N from human activities is limited. We used N and oxygen stable isotope ratios of dissolved inorganic N (DIN) and concentrations of artificial sweeteners to identify the relative contribution of key sources of anthropogenic N (i.e., fertilizers, human, and livestock waste) to tributaries of the Red River Valley (RRV), Manitoba, Canada. Water and algae were sampled in 14 RRV tributaries during snowmelt, spring, summer, and autumn; and water was sampled at three locations in the Red River in spring, summer, and autumn. δN values of DIN in tributary water differed seasonally and were greatest during snowmelt. Incorporation of ammonium δN provided evidence for the importance of manure N to tributaries during snowmelt. Fertilizer and municipal lagoons served as principal sources of N to streams in spring and summer. Human and livestock waste sources of N were the dominant contributor to algae at greater than 90% of sites and algae δN was greatest at sites downstream of municipal lagoons. We also showed that the tributaries contribute human and livestock waste N to the Red River, though much of the nitrate in the river originates outside of Manitoba. Overall, our study determined that the anthropogenic sources of N to RRV streams vary seasonally, likely due to regional hydrologic conditions. Our study also showed the potential of artificial sweeteners and ammonium δN as tools for identifying N sources to rivers. Moreover, we demonstrate the need for the management of N sources and the protection of stream function to control downstream transfer of N from landscapes to waterbodies.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142824DOI Listing
April 2021

Australia's prehistoric 'swamp king': revision of the Plio-Pleistocene crocodylian genus de Vis, 1886.

PeerJ 2020 21;8:e10466. Epub 2020 Dec 21.

School of Biological Sciences, The Univeristy of Queensland, Brisbane, QLD, Australia.

The crocodylian fossil record from the Cenozoic of Australasia is notable for its rich taxonomic diversity, and is primarily represented by members of the clade Mekosuchinae. Reports of crocodylian fossils from Australia date back to the late nineteenth century. In 1886, Charles Walter de Vis proposed the name for crocodylian fossils from southeast Queensland-the first binomen given to an extinct crocodylian taxon from Australia. has come to be regarded as a large, broad-snouted crocodylian from Australia's Plio-Pleistocene, and numerous specimens, few of which are sufficiently complete, have been assigned to it by several authors throughout the twentieth century. In the late 1990s, the genus was expanded to include a second species, . Unfortunately, the original syntype series described as is very fragmentary and derives from more than one taxon, while a large part of the subsequently selected lectotype specimen is missing. Because descriptions and illustrations of the complete lectotype do not reveal any autapomorphic features, we propose that should be regarded as a . Following this decision, the fossil material previously referred to is of uncertain taxonomic placement. A partial skull, formerly assigned to and known as 'Geoff Vincent's specimen', possesses many features of diagnostic value and is therefore used as basis to erect a new genus and species gen. et sp. nov. A comprehensive description is given for the osteology of 'Geoff Vincent's specimen' as well as aspects of its palaeoneurology, the latter being a first for an extinct Australian crocodyliform. The newly named genus is characterized by a unique combination of premaxillary features such as a distinctive arching of the anterior alveolar processes of the premaxillae, a peculiar arrangement of the first two premaxillary alveoli and a large size disparity between the 3rd and 4th premaxillary alveoli. These features presently allow formal recognition of two species within the genus, and comb. nov., with the former having comparatively more robust rostral proportions than the latter. The holotype comes from the Pliocene Chinchilla Sand of the Darling Downs, south-eastern Queensland, whereas the material assigned to is from the Pleistocene of Terrace Site Local Fauna, Riversleigh, northwest Queensland. Phylogenetic analyses recover as a mekosuchine, although further cladistic assessments are needed to better understand the relationships within the clade.
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http://dx.doi.org/10.7717/peerj.10466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7759136PMC
December 2020

Crayfish tissue metabolomes effectively distinguish impacts of wastewater and agriculture in aquatic ecosystems.

Sci Total Environ 2021 Mar 4;760:143322. Epub 2020 Nov 4.

Western University and Canadian Rivers Institute, Department of Geography, London, ON N6A 5C2, Canada.

Environmental metabolomics has been proposed as a tool for biomonitoring because organisms regulate production or consumption of metabolites in response to environmental conditions. We evaluated the efficacy of the metabolome of three tissues (hepatopancreas, gill, and tail muscle) from the northern crayfish (Faxonius virilis) to detect and differentiate between impacts of human activities (i.e., reference, municipal wastewater, and agriculture). We conducted a reciprocal transfer study exposing crayfish for 1 or 2 weeks in three streams with different amounts and types of human activities in southern Manitoba, Canada. Tissue samples were analyzed using nuclear magnetic resonance spectroscopy to generate a metabolic profile. Findings indicated the gill tissue metabolome best detected and differentiated between human activities. In particular, the gill metabolome was able to rapidly integrate abrupt changes in environmental conditions associated with municipal wastewater activity. In contrast, the tail metabolome best differentiated between crayfish collected at the reference site from those collected at the two impacted sites. Metabolites extracted from hepatopancreas tissue showed limited and inconsistent detection of among site differences. Based on our findings, we conclude that the metabolome of the northern crayfish can be an effective biomonitoring tool, but monitoring purpose will dictate tissue selection. Indeed, we recommend the gill metabolome be used for short-term assays aimed at detecting acute effects, whereas the tail be applied for survey monitoring aimed at detecting deviations in ecological condition at test sites from reference site conditions.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143322DOI Listing
March 2021

Fate of bioavailable nutrients released to a stream during episodic effluent releases from a municipal wastewater treatment lagoon.

Environ Sci Process Impacts 2020 Dec;22(12):2374-2387

The University of Western Ontario and Canadian Rivers Institute, Department of Geography, 1151 Richmond Street, London, Ontario N6A 5C2, Canada.

Municipal wastewater lagoons are common across North America and, unlike larger mechanical wastewater treatment plants, typically release nutrient-rich effluent directly to rivers in intermittent pulses. However, little is known about the fate of nutrients from these episodic events, which may happen under varying hydrologic or thermal conditions. We assessed fate of nitrogen (N) and phosphorus (P) from lagoon effluent during three releases to Deadhorse Creek, Manitoba, Canada. Using net nutrient uptake lengths and natural abundance stable isotope ratios of dissolved inorganic nitrogen (DIN) and primary producers, we found that DIN was processed during the summer releases though the dominant mechanism was unclear. However, nitrate was largely exported in autumn. Primary producers assimilated lagoon N but did not appear to reduce DIN concentrations. The longitudinal pattern of soluble reactive phosphorus (SRP) varied between releases and in summer 2019 the stream became a net source of SRP despite concomitant processing of DIN. We hypothesize that low demand for P in Deadhorse Creek, as suggested by upstream SRP > 0.05 mg P L-1, and nutrient ratios indicative of N limitation, reduced instream processing of P. Furthermore, our results indicated that cool or high flow conditions may result in the export of much of the lagoon nutrient load downstream. Our findings suggest the processes that transform wastewater nutrients are overwhelmed during effluent releases. Managers should consider increasing effluent dilution via continuous release of effluent rather than pulsed delivery. However, management of upstream nutrient supply may also be needed when relying upon the self-purifying capacity of rivers.
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http://dx.doi.org/10.1039/d0em00315hDOI Listing
December 2020

Episodic loadings of phosphorus influence growth and composition of benthic algae communities in artificial stream mesocosms.

Water Res 2020 Oct 3;185:116139. Epub 2020 Aug 3.

University of Western Ontario & Canadian Rivers Institute, 1156 Richmond Street, London, Ontario, Canada.

Phosphorus (P) is an essential macronutrient for algal communities, but in excess can exacerbate stream eutrophication. However, P loadings to streams vary temporally from continuous to episodic as a result of inputs from point and non-point sources, respectively. P loading pattern can thus alter the temporal availability of P and may influence effects of P enrichment on algal communities. We assessed how P loading pattern influences algal biomass and composition by conducting a 29-day P enrichment experiment in nine artificial streams exposed to either: (1) continuous P enrichment; (2) episodic P enrichment, or; (3) no P enrichment. P enrichment increased algal biomass accrual, but peak biomass did not differ between continuously and episodically enriched treatments. Maximum absolute growth rates were also comparable between P enriched treatments. However, episodic P additions sustained elevated rates of biomass accrual, whereas absolute growth rates in the continuously enriched communities declined towards the end of the experiment. P enrichment resulted in comparable increases in relative abundance of chlorophytes and decreased proportions of bacillariophytes and charophytes in algal communities for continuously and episodically enriched treatments. However, composition of bacillariophyte (diatom) assemblages differed significantly among all P enrichment treatments in accordance with species autecological attributes for P. Our results demonstrate that episodic and continuous P enrichment may augment algal biomass similarly. Yet, P loading pattern regulated the composition of algal communities. Thus, remedial management strategies for the control of nuisance algae production may require focus on the predominant source of P to streams. Finally, species specific responses of diatom assemblages to P enrichment and associated loading patterns suggests this taxonomic group may have potential as diagnostic indicators for identifying the presence of key nutrient sources associated with eutrophication of stream ecosystems.
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http://dx.doi.org/10.1016/j.watres.2020.116139DOI Listing
October 2020

A Rotated and Laterally Displaced Patellar Dislocation.

J Emerg Med 2020 Jul 23;59(1):121-124. Epub 2020 May 23.

University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.

Background: Patellar dislocations are a common orthopedic emergency with several variants. The rarer variants include rotational dislocations. These often require open reduction in the operating room.

Case Report: We report on a case of a combined rotational and lateral patellar dislocation in a young female. We suspected and made the diagnosis of a rotational dislocation after initial unsuccessful attempts at reduction under sedation. With the assistance of our orthopedic colleagues, we were able to perform a reduction of this patient's patella under sedation in the emergency department. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Awareness of uncommon patellar dislocations is an important area of knowledge for the emergency physician. A thorough understanding of indications and contraindications to closed reduction is important for efficient and safe management and disposition. Collaboration with orthopedic surgery colleagues is another important step in the evaluation of these patients.
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http://dx.doi.org/10.1016/j.jemermed.2020.04.034DOI Listing
July 2020

Determining hematological, biochemical and immunological reference values in healthy adults with high-risk for HIV acquisition in Mozambique.

PLoS One 2020 30;15(4):e0232018. Epub 2020 Apr 30.

Centro de Investigação e Treino em Saúde da Polana Caniço (CISPOC), Instituto Nacional de Saúde (INS), Ministério da Saúde (MISAU), Maputo, Mozambique.

Introduction: In many African countries, laboratory reference values are not established for the local healthy adult population. In Mozambique, reference values are known for young adults (18-24yo) but not yet established for a wider age range. Our study aimed to establish hematological, biochemical and immunological reference values for vaccine trials in Mozambican healthy adults with high-risk for HIV acquisition.

Methods: A longitudinal cohort and site development study in Mozambique between November 2013 and 2014 enrolled 505 participants between 18 to 35 years old. Samples from these healthy participants, were analyzed to determine reference values. All volunteers included in the analysis were clinically healthy and human immunodeficiency virus (HIV), hepatitis B and C virus, and syphilis negative. Median and reference ranges were calculated for the hematological, biochemical and immunological parameters. Ranges were compared with other African countries, the USA and the US National Institute of Health (NIH) Division of AIDS (DAIDS) toxicity tables.

Results: A total of 505 participant samples were analyzed. Of these, 419 participants were HIV, hepatitis B and C virus and syphilis negative including 203 (48.5%) females and 216 (51.5%) males, with a mean age of 21 years. In the hematological parameters, we found significant differences between sex for erythrocytes, hemoglobin, hematocrit, MCV, MCH and MCHC as well as white blood cells, neutrophils and platelets: males had higher values than females. There were also significant differences in CD4+T cell values, 803 cells/μL in men versus 926 cells/μL in women. In biochemical parameters, men presented higher values than women for the metabolic, enzymatic and renal parameters: total and direct bilirubin, ALT and creatinine.

Conclusion: This study has established reference values for healthy adults with high-risk for HIV acquisition in Mozambique. These data are helpful in the context of future clinical research and patient care and treatment for the general adult population in the Mozambique and underline the importance of region-specific clinical reference ranges.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0232018PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7192423PMC
July 2020

Global patterns and drivers of ecosystem functioning in rivers and riparian zones.

Sci Adv 2019 01 9;5(1):eaav0486. Epub 2019 Jan 9.

River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.
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http://dx.doi.org/10.1126/sciadv.aav0486DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326750PMC
January 2019

Developing metabolomics-based bioassessment: crayfish metabolome sensitivity to food and dissolved oxygen stress.

Environ Sci Pollut Res Int 2018 Dec 25;25(36):36184-36193. Epub 2018 Oct 25.

Department of Geography, Western University and Canadian Rivers Institute, London, ON, N6A 5C2, Canada.

There is a need to develop bioassessment tools that can diagnose the effects of individual stressors that can have multiple ecological effects. Using nuclear magnetic resonance (NMR)-based metabolomics, our experiments aimed to identify the sensitivity of metabolites to changes in food availability and dissolved oxygen (DO) concentrations, and compare these results to identify metabolites that may differentiate between the effects of these two stressors. Forty-eight, laboratory-raised, red swamp crayfish (Procambarus clarkii) were randomly assigned and exposed to one of three food availability or DO treatment levels (high, normal, low). Starved crayfish had lower amounts of amino acids than fed crayfish, suggesting catabolic effects of starvation on tail muscle tissue for energy requirements. In contrast, crayfish exposed to hypoxic conditions experienced changes in abundance of metabolites primarily associated with energy metabolism. Tail muscle was the only tissue sensitive to food and DO stress, suggesting the need to select tissues for monitoring appropriately. Our evaluation of environmental metabolomics as a tool for bioassessment indicates that several identified metabolites in crayfish tail muscle may be able to diagnose food and oxygen stress. Further study is required to determine if these metabolic effects are linked with changes of individual fitness and higher levels of biological organization, such as population size.
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http://dx.doi.org/10.1007/s11356-018-3518-5DOI Listing
December 2018

Tip-dating and homoplasy: reconciling the shallow molecular divergences of modern gharials with their long fossil record.

Proc Biol Sci 2018 06 27;285(1881). Epub 2018 Jun 27.

Museum of Central Australia, Museum and Art Gallery of the Northern Territory, 4 Memorial Avenue, Alice Springs, Northern Territory 0870, Australia.

Simultaneously analysing morphological, molecular and stratigraphic data suggests a potential resolution to a major remaining inconsistency in crocodylian evolution. The ancient, long-snouted thoracosaurs have always been placed near the Indian gharial , but their antiquity ( 72 Ma) is highly incongruous with genomic evidence for the young age of the lineage ( 40 Ma). We reconcile this contradiction with an updated morphological dataset and novel analysis, and demonstrate that thoracosaurs are an ancient iteration of long-snouted stem crocodylians unrelated to modern gharials. The extensive similarities between thoracosaurs and are shown to be an almost 'perfect storm' of homoplasy, combining convergent adaptions to fish-eating, as well resemblances between genuinely primitive traits (thoracosaurs) and atavisms (). Phylogenetic methods that ignore stratigraphy (parsimony and undated Bayesian methods) are unable to tease apart these similarities and invariably unite thoracosaurs and However, tip-dated Bayesian approaches additionally consider the large temporal gap separating ancient (thoracosaurs) and modern () iterations of similar long-snouted crocodyliforms. These analyses robustly favour a phylogeny which places thoracosaurs basal to crocodylians, far removed from modern gharials, which accordingly are a very young radiation. This phylogenetic uncoupling of ancient and modern gharial-like crocs is more consistent with molecular clock divergence estimates, and also the bulk of the crocodylian fossil record (e.g. all unequivocal gharial fossils are very young). Provided that the priors and models attribute appropriate relative weights to the morphological and stratigraphic signals-an issue that requires investigation-tip-dating approaches are potentially better able to detect homoplasy and improve inferences about phylogenetic relationships, character evolution and divergence dates.
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http://dx.doi.org/10.1098/rspb.2018.1071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6030529PMC
June 2018

Variation in the pelvic and pectoral girdles of Australian Oligo-Miocene mekosuchine crocodiles with implications for locomotion and habitus.

PeerJ 2017 30;5:e3501. Epub 2017 Jun 30.

PANGEA Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.

Australian Oligo-Miocene mekosuchines (Crocodylia; Crocodyloidea) display wide diversity in cranial shape and inferred hunting strategies. Terrestrial habitus has been inferred for these distinctive predators. A direct morphological signal for locomotion can be expected in the postcrania, particularly the pelvic and pectoral girdles. Here we describe fossil materials of the girdles, which chart their morphological variation in the subfamily from Eocene through to Middle Miocene. Over this period, both girdles undergo significant morphological changes. Notably, an enclosed, ventrally orientated acetabulum in the ilium is developed in one lineage. This recapitulates the erect parasagittal configuration of the pelvic limb seen in many Mesozoic crocodylomorph lineages, suggesting consistent use of erect high-walking in these mekosuchines. Other pelves from the same Oligo-Miocene deposits display morphology closer to modern crocodilians, suggesting a partitioning of locomotory strategy among sympatric mekosuchines. Plesiomorphic and derived pelvic girdles are distinguishable by parsimony analysis, and the earliest examples of the mekosuchine pelvis more closely resemble gavialids and alligatorids while latter forms converge on crown group crocodylids in the morphology of the iliac crest. This suggests that a revaluation of the base relationship of Mekosuchinae within Eusuchia is necessary.
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http://dx.doi.org/10.7717/peerj.3501DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5494174PMC
June 2017

The biochronology and palaeobiogeography of (Crocodylia: Mekosuchinae) based on new specimens from the Northern Territory and Queensland, Australia.

Authors:
Adam M Yates

PeerJ 2017 21;5:e3458. Epub 2017 Jun 21.

Museum of Central Australia, Museum and Art Gallery of the Northern Territory, Alice Springs, NT, Australia.

New records of the Oligo-Miocene mekosuchine crocodylian, , from Queensland and the Northern Territory are described. and are accepted as valid species in the genus and their diagnoses are revised. Both species are present in Queensland and the Northern Territory but are restricted in time, with known from the late Oligocene and from the middle Miocene. The broad geographic distributions and restricted time spans of these species indicate that this genus is useful for biochronology. The record of from the Pwerte Marnte Marnte Local Fauna in the Northern Territory establishes that the species inhabited the north-western margin of the Lake Eyre Basin (LEB) drainage system. More southerly Oligo-Miocene sites in the LEB contain only one crocodylian species, . The Pwerte Marnte Marnte occurrence of indicates that the separation of and did not correspond with the boundaries of drainage basins and that palaeolatitude was a more likely segregating factor.
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http://dx.doi.org/10.7717/peerj.3458DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5482264PMC
June 2017

Intra-annual variation of the association between agricultural best management practices and stream nutrient concentrations.

Sci Total Environ 2017 May 17;586:1124-1134. Epub 2017 Feb 17.

Department of Geography, Western University and Canadian Rivers Institute, 1151 Richmond Street, London, ON N6A 3K7, Canada. Electronic address:

Temporal variation may influence the ability of best management practices (BMPs) to mitigate the loss of agricultural pollutants to streams. Our goal was to assess variation in mitigation effects of BMPs by examining the associations between instream nutrient concentrations and the abundance and location of four structural BMPs over a hydrologic year. Water samples were collected monthly (Nov. 2013-Oct. 2014) in 15 headwater streams representing a gradient of BMP use in Southern Ontario, Canada. Partial least squares (PLS) regression models were used to associate two groups of collinear nutrient forms with the abundance and location of BMPs, antecedent precipitation and time of year. BMP metrics in PLS models were associated with instream concentrations of major phosphorus forms and ammonium throughout the year. In contrast, total nitrogen and nitrate-nitrite were only associated with BMPs during snowmelt. BMP metrics associated with reductions of phosphorus and ammonium included greater abundances of riparian buffers and manure storage structures, but not livestock restriction fences. Likewise, the abundance and location riparian vegetation in areas capturing more surface runoff were associated with decreased stream nitrogen concentrations during snowmelt. However, the amount of tile drainage was associated with increased nitrogen concentrations following snowmelt, as well as with greater phosphorus and ammonium concentrations throughout the year. Overall, our findings indicate that increasing the abundance of riparian buffers and manure storage structures may decrease instream nutrient concentrations in agricultural areas. Additionally, the implementation of these structural BMPs appear to be an effective year-round strategy to assist management objectives in reducing phosphorus concentrations in small agricultural streams and thus loadings to downstream tributaries. Further mitigation measures, such as managerial BMPs and controlled tile drainage, may be required to further reduce instream nutrient concentrations during baseflow periods and snowmelt events.
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http://dx.doi.org/10.1016/j.scitotenv.2017.02.102DOI Listing
May 2017

Cutting Corners: Provider Perceptions of Interpretation Services and Factors Related to Use of an Ad Hoc Interpreter.

Hisp Health Care Int 2016 06 29;14(2):73-80. Epub 2016 Apr 29.

Clemson University, Clemson, SC, USA.

Introduction: This study assessed health providers' perceptions of factors related to professional interpretation services and the association between these factors and the potential use of ad hoc interpreters.

Method: Data were collected from a convenience sample of 150 health services providers at a large, regional health system in South Carolina.

Results: Providers rated "ability to communicate effectively during a clinical encounter" as paramount regarding the use of interpretation services. The most important factors related to the likely use of ad hoc interpreters (cutting corners) included locating a qualified interpreter, having to wait for a qualified interpreter, and technical difficulties regarding phone and video technology.

Conclusion: Health care organizations may benefit from increasing staff awareness about patient safety and legal and regulatory risks involved with the use of ad hoc interpreters.
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http://dx.doi.org/10.1177/1540415316646097DOI Listing
June 2016

Effects of Best Management Practice on Ecological Condition: Does Location Matter?

Environ Manage 2016 May 20;57(5):1062-76. Epub 2016 Jan 20.

Department of Geography, Western University & Canadian Rivers Institute, 1151 Richmond St, London, ON, N6A 5B7, Canada.

Best management practices (BMPs) are increasingly being promoted as a solution to the potentially adverse effects agriculture can have on aquatic systems. However, the ability of BMPs to improve riverine systems continues to be questioned due to equivocal empirical evidence linking BMP use with improved stream conditions, particularly in regard to ecological conditions. Explicitly viewing BMP location in relation to hydrological pathways may, however, assist in establishing stronger ecological linkages. The goal of this study was to assess the association between water chemistry, benthic macroinvertebrate community structure, and the number and location of agricultural BMPs in a catchment. Macroinvertebrate and water samples were collected in 30 small (<12 km(2)) catchments exhibiting gradients of BMP use and location in the Grand River Watershed, Southern Ontario, Canada. Stepwise regression analysis revealed that concentrations of most stream nutrients declined in association with greater numbers of BMPs and particularly when BMPs were located in hydrologically connected areas. However, BMPs were significantly associated with only one metric (%EPT) describing macroinvertebrate community structure. Furthermore, variance partitioning analysis indicated that less than 5% of the among site variation in the macroinvertebrate community could be attributed to BMPs. Overall, the implemented BMPs appear to be achieving water quality improvement goals but spatial targeting of specific BMP types may allow management agencies to attain further water quality improvements more efficiently. Mitigation and rehabilitation measures beyond the BMPs assessed in this study may be required to meet goals of enhanced ecological condition.
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http://dx.doi.org/10.1007/s00267-016-0662-xDOI Listing
May 2016

New craniodental remains of Wakaleo alcootaensis (Diprotodontia: Thylacoleonidae) a carnivorous marsupial from the late Miocene Alcoota Local Fauna of the Northern Territory, Australia.

Authors:
Adam M Yates

PeerJ 2015 12;3:e1408. Epub 2015 Nov 12.

Museum of Central Australia, Museum and Art Gallery of the Northern Territory , Alice Springs, Northern Territory , Australia.

New jaws and teeth referable to the rare thylacoleonid marsupial Wakaleo alcootaensis are figured and described. The species is the geologically youngest known member of the genus and is only known from the late Miocene Alcoota Local Fauna of the Northern Territory, Australia. A revised diagnosis of the species is presented which is found to be morphologically distinct from its congeners. W. alcootaensis can be distinguished from other species of Wakaleo by its greater size, deeply recessed masseteric fossa, more steeply angled I1, loss of P2, greater P3 to M1 ratio and loss of M3. Several characters of W. alcootaensis, including the increase in size, steeply angled I1, increase of the relative size of P3, and reduction of the molar row are present in at least some species of Thylacoleo. Phylogenetic analysis suggests that these character states are convergences and that there was parallel evolution in these two thylacoleonid lineages.
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http://dx.doi.org/10.7717/peerj.1408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4647553PMC
November 2015

A new basal sauropod from the pre-Toarcian Jurassic of South Africa: evidence of niche-partitioning at the sauropodomorph-sauropod boundary?

Sci Rep 2015 Aug 19;5:13224. Epub 2015 Aug 19.

Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, Gauteng, 2050, South Africa.

The early evolution of sauropod dinosaurs remains poorly understood, with a paucity of unequivocal sauropod taxa known from the first twenty million years of the Jurassic. Recently, the Early Jurassic of South Africa has yielded an assemblage of dental and post-cranial remains displaying a more apomorphic character suite than any other similarly aged sauropodomorph. These remains are interpreted as a new species of basal sauropod and recovered cladistically as the sister taxon to Vulcanodon +more derived Sauropoda, underscoring its importance for our understanding of this pivotal period of sauropod evolution. Key changes in the dentition, axial skeleton and forelimb of this new species suggest a genuine functional distinction occurring at the sauropodiform-sauropod boundary. With reference to these changes, we propose a scenario in which interdependent refinements of the locomotory and feeding apparatus occurred in tandem with, or were effected by, restrictions in the amount of vertical forage initially available to the earliest sauropods. The hypothesized instance of niche-partitioning between basal sauropodan taxa and higher-browsing non-sauropodan sauropodomorphs may partially explain the rarity of true sauropods in the basal rocks of the Jurassic, while having the added corollary of couching the origins of Sauropoda in terms of an ecologically delimited 'event'.
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http://dx.doi.org/10.1038/srep13224DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4541066PMC
August 2015

Thylacinus (Marsupialia: Thylacinidae) from the Mio-Pliocene boundary and the diversity of Late Neogene thylacinids in Australia.

Authors:
Adam M Yates

PeerJ 2015 12;3:e931. Epub 2015 May 12.

Museum and Art Gallery of the Northern Territory, Museum of Central Australia , Alice Springs, Northern Territory , Australia.

Thylacinus yorkellus is described as a new, moderately small-bodied species of thylacinid from the latest Miocene or, more likely, earliest Pliocene of South Australia. The new species can be diagnosed by the autapomorphic presence a strongly developed precingulid that terminates in a cuspidule on the anterobuccal face of the paraconid of the lower molars and a tiny basal anterior cuspidule on P 2, P 3 and the lower molars. It is found by cladistic analysis to be the sister species of the recently extinct Th. cynocephalus and distinct from the approximately coeval Th. megiriani from the Northern Territory. New dentary material is described and referred to Th. megiriani. These add character data and allow this species to be re-diagnosed based on autapomorphic character traits. Each of the three known late Miocene to early Pliocene Thylacinus species (Th. potens, Th. megiriani and Th. yorkellus) suggest that, instead of declining, there was a modest radiation of Thylacinus in the late Miocene.
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http://dx.doi.org/10.7717/peerj.931DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4435473PMC
May 2015

New craniodental remains of Thylacinus potens (Dasyuromorphia: Thylacinidae), a carnivorous marsupial from the late Miocene Alcoota Local Fauna of central Australia.

Authors:
Adam M Yates

PeerJ 2014 28;2:e547. Epub 2014 Aug 28.

Museums and Art Galleries of the Northern Territory , Museum of Central Australia, Alice Springs, Northern Territory , Australia.

New craniodental specimens that are referrable to the thylacinid marsupial, Thylacinus potens, are described from the late Miocene Alcoota Local Fauna of the Northern Territory, Australia. The remains include a largely complete maxilla and dentary, showing for the first time the anterior dentition of the dentary. The new remains indicate that Th. potens was a more variable species than previously recognised. The dentary, in particular, is more gracile, than other specimens referred to this species. A revised apomorphy-based diagnosis of Th. potens that takes this variability into account is presented. A cladistic analysis supports previous analyses that placed Th. potens in a derived position within Thylacinidae, close to the modern Th. cynocephalus. New estimations of body size are made using published regressions of dental measurements of dasyuromorphians as well as by assuming geometric similitude with Th. cynocephalus. All methods produce body mass estimates in excess of 35 kg.
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http://dx.doi.org/10.7717/peerj.547DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4157238PMC
September 2014

A new species of long-necked turtle (Pleurodira: Chelidae: Chelodina) from the late Miocene Alcoota Local Fauna, Northern Territory, Australia.

Authors:
Adam M Yates

PeerJ 2013 1;1:e170. Epub 2013 Oct 1.

Museums and Art Galleries of the Northern Territory, Museum of Central Australia , Alice Springs, Northern Territory , Australia.

The new species Chelodina (Chelodina) murrayi is described from the late Miocene Alcoota Local Fauna of central Australia, in the Northern Territory. The new species is based on shell fragments and can be diagnosed by a ventrally reflexed anterior margin of the plastron, a ventrally narrowed cervical scute and strongly dorsally curved margins of the carapace extending from approximately peripheral two to peripheral nine or ten as well as by a unique combination of characters. Within Chelodina the new species is part of the nominal subgenus and within that subgenus it is most closely related to the Chelodina (Chelodina) novaeguineae species group. This is not only the oldest record but also the most southerly occurrence of this species group.
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http://dx.doi.org/10.7717/peerj.170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3796373PMC
October 2013

What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

PLoS One 2013 9;8(10):e75216. Epub 2013 Oct 9.

Biology Program, The Richard Stockton College of New Jersey, Galloway, New Jersey, United States of America.

Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0075216PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3793987PMC
June 2014

Synchrotron Reveals Early Triassic Odd Couple: Injured Amphibian and Aestivating Therapsid Share Burrow.

PLoS One 2013 21;8(6):e64978. Epub 2013 Jun 21.

Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, Gauteng, South Africa.

Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of vertebrate remains associated with these burrows leaves many ecological questions unanswered. Synchrotron scanning of a lithified burrow cast from the Early Triassic of the Karoo unveiled a unique mixed-species association: an injured temnospondyl amphibian (Broomistega) that sheltered in a burrow occupied by an aestivating therapsid (Thrinaxodon). The discovery of this rare rhinesuchid represents the first occurrence in the fossil record of a temnospondyl in a burrow. The amphibian skeleton shows signs of a crushing trauma with partially healed fractures on several consecutive ribs. The presence of a relatively large intruder in what is interpreted to be a Thrinaxodon burrow implies that the therapsid tolerated the amphibian's presence. Among possible explanations for such unlikely cohabitation, Thrinaxodon aestivation is most plausible, an interpretation supported by the numerous Thrinaxodon specimens fossilised in curled-up postures. Recent advances in synchrotron imaging have enabled visualization of the contents of burrow casts, thus providing a novel tool to elucidate not only anatomy but also ecology and biology of ancient tetrapods.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0064978PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3689844PMC
October 2017

A descriptive study of myoclonus associated with etomidate procedural sedation in the ED.

Am J Emerg Med 2013 May 1;31(5):852-4. Epub 2013 Apr 1.

Department of Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA.

Background: Myoclonus is a well-recognized side effect of etomidate when given in induction doses for rapid sequence intubation. Most of the data reported on myoclonus with emergency department (ED) sedation doses are reported as a secondary finding.

Study Objectives: Our objective was to prospectively quantify the incidence and duration of myoclonus associated with the administration of etomidate in the lower doses given for procedural sedation in the ED.

Methods: This was a prospective descriptive study performed between September 2008 and September 2010 at an urban teaching hospital ED with approximately 50000 patient visits per year. Procedural sedation was performed at the discretion of the treating emergency physician, and adult patients receiving etomidate were eligible for enrollment. The occurrence and duration of myoclonus were observed and recorded. Any interference of myoclonus with the ability to complete the procedure was recorded, and adverse effects were identified.

Results: Thirty-four eligible subjects were enrolled, and 36 separate sedation procedures were performed. The mean initial etomidate dose was 0.13 mg/kg (range, 0.077-0.20), and the mean total etomidate dose was 0.15 mg/kg (range, 0.077-0.29). Myoclonus was noted in 26 (72%) of 36 sedations. Mean time to onset of myoclonus was 50 seconds (range, 15-146), and the mean duration was 93 seconds (range, 03-557). Myoclonus interfered with the procedure in only 1 (3%) of 36 attempted procedures, and no procedure was unsuccessful because of myoclonus.

Conclusion: Myoclonus associated with sedation doses of etomidate was common but rarely interfered with the completion of a procedure.
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http://dx.doi.org/10.1016/j.ajem.2013.02.042DOI Listing
May 2013

Esrrb is a direct Nanog target gene that can substitute for Nanog function in pluripotent cells.

Cell Stem Cell 2012 Oct;11(4):477-90

MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, Scotland.

Embryonic stem cell (ESC) self-renewal efficiency is determined by the level of Nanog expression. However, the mechanisms by which Nanog functions remain unclear, and in particular, direct Nanog target genes are uncharacterized. Here we investigate ESCs expressing different Nanog levels and Nanog(-/-) cells with distinct functionally inducible Nanog proteins to identify Nanog-responsive genes. Surprisingly, these constitute a minor fraction of genes that Nanog binds. Prominent among Nanog-reponsive genes is Estrogen-related receptor b (Esrrb). Nanog binds directly to Esrrb, enhances binding of RNAPolII, and stimulates Esrrb transcription. Overexpression of Esrrb in ESCs maintains cytokine-independent self-renewal and pluripotency. Remarkably, this activity is retained in Nanog(-/-) ESCs. Moreover, Esrrb can reprogram Nanog(-/-) EpiSCs and can rescue stalled reprogramming in Nanog(-/-) pre-iPSCs. Finally, Esrrb deletion abolishes the defining ability of Nanog to confer LIF-independent ESC self-renewal. These findings are consistent with the functional placement of Esrrb downstream of Nanog.
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http://dx.doi.org/10.1016/j.stem.2012.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3473361PMC
October 2012

Snowmelt and its role in the hydrologic and nutrient budgets of prairie streams.

Water Sci Technol 2011 ;64(8):1590-6

Environment Canada, 867 Lakeshore Rd, P.O. BOX 5050, Burlington, Ontario, Canada L7R 4A6.

Small watersheds in the Canadian Prairies are characterized by seasonally disconnected hydrologic networks whereby stream channels are hydrologically connected during snowmelt but have disconnected reaches throughout the remainder of the year. Snowmelt is the most significant hydrological event in the Canadian Prairies, yet few studies have investigated the role of snowmelt in the nutrient budget of prairie streams. We quantified hydrologic and nutrient dynamics during snowmelt for ten agricultural subwatersheds distributed along a gradient of human activity in the Red River Valley, Canada, to evaluate the timing of nitrogen (N) and phosphorus (P) export. Elevated concentrations of total P (TP) and total N (TN) were observed during the snowmelt peak, with maximum concentrations reaching 3.23 mg TP L(-1) and 18.50 mg TN L(-1). Dissolved P and N dominated the total nutrient pool throughout snowmelt, likely due to reduced erosion and sediment transport resulting from the combination of the flat topography, frozen soil and stream banks, and gradual snow cover melt. Significant correlations were observed between snowmelt N load (r=0.91; p<0.05) and both agricultural land cover and fertilizer usage, with a weaker correlation between snowmelt P load (r=0.81; p<0.05) and agricultural area. Our results showed that snowmelt plays a key role in nutrient export to prairie aquatic ecosystems and this may have serious impacts on downstream ecosystems. Land use management practices need to consider the snowmelt period to control nutrient loads to Lake Winnipeg and other waterbodies in the Great Plains.
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http://dx.doi.org/10.2166/wst.2011.676DOI Listing
April 2012

The earliest post-paleozoic freshwater bivalves preserved in coprolites from the karoo basin, South Africa.

PLoS One 2012 2;7(2):e30228. Epub 2012 Feb 2.

Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, Johannesburg, South Africa.

Background: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic.

Principal Findings: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic) of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative.

Conclusions: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0030228PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3271088PMC
September 2012

Oldest known dinosaurian nesting site and reproductive biology of the Early Jurassic sauropodomorph Massospondylus.

Proc Natl Acad Sci U S A 2012 Feb 24;109(7):2428-33. Epub 2012 Jan 24.

Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.

The extensive Early Jurassic continental strata of southern Africa have yielded an exceptional record of dinosaurs that includes scores of partial to complete skeletons of the sauropodomorph Massospondylus, ranging from embryos to large adults. In 1976 an incomplete egg clutch including in ovo embryos of this dinosaur, the oldest known example in the fossil record, was collected from a road-cut talus, but its exact provenance was uncertain. An excavation program at the site started in 2006 has yielded multiple in situ egg clutches, documenting the oldest known dinosaurian nesting site, predating other similar sites by more than 100 million years. The presence of numerous clutches of eggs, some of which contain embryonic remains, in at least four distinct horizons within a small area, provides the earliest known evidence of complex reproductive behavior including site fidelity and colonial nesting in a terrestrial vertebrate. Thus, fossil and sedimentological evidence from this nesting site provides empirical data on reproductive strategies in early dinosaurs. A temporally calibrated optimization of dinosaurian reproductive biology not only demonstrates the primary significance of the Massospondylus nesting site, but also provides additional insights into the initial stages of the evolutionary history of dinosaurs, including evidence that deposition of eggs in a tightly organized single layer in a nest evolved independently from brooding.
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http://dx.doi.org/10.1073/pnas.1109385109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3289328PMC
February 2012

Heat stroke: helping patients keep their cool.

Nurse Pract 2011 May;36(5):48-52

UPMC Mercy, Department of Emergency Medicine, Pittsburgh, PA, USA.

Heat stroke is a life-threatening illness that requires prompt diagnosis and treatment. Early vital sign assessment and history gathering are key to identifying this disorder.
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http://dx.doi.org/10.1097/01.NPR.0000396476.99238.39DOI Listing
May 2011