84 research outputs found
Discovery of new colonies by Sentinel2 reveals good and bad news for emperor
The distribution of emperor penguins is circumpolar, with 54 colony locations currently reported of which 50 are currently extant as of 2019. Here we report on eight newly discovered colonies and confirm the rediscovery of three breeding sites, only previously reported in the era before Very High Resolution satellite imagery was available, making a total of 61 breeding locations. This represents an increase of ~20% in the number of breeding sites, but, as most of the colonies appear to be small, they may only increase the total population by around 5â10%. The discoveries have been facilitated by the use of Sentinel2 satellite imagery, which has a higher resolution and more efficient search mechanism than the Landsat data previously used to search for colonies. The small size of these new colonies indicates that considerations of reproductive output in relation to metabolic rate during huddling is likely to be of interest. Some of the colonies exist in offshore habitats, something not previously reported for emperor penguins. Comparison with recent modelling results show that the geographic locations of all the newly found colonies are in areas likely to be highly vulnerable under businessâasâusual greenhouse gas emissions scenarios, suggesting that population decreases for the species will be greater than previously thought
Spider silk protein structure analysis by FTIR and STXM spectromicroscopy techniques
Spider silk displays incredible strength and elasÂŹticity for its size and weight.[1] These properties have sparked interest in determining the protein structures of the silk fibers allowing for the proÂŹduction of synthetic silks.[2] This study compares the mid-infrared (Mid IR) spectra of silk from five different spider species to investigate the com-monalities between species and web type. The results demonstrate the Mid IR spectra from all types of spider silk to be similar, showing protein peaks in the Amide I and II regions. To study the environmental effects of the acid solution on the silk protein structure, two of the five speciesâ silk: Black & Yellow Orb Weaver (Argiope aurantia) and Black Widow (Latrodectus hesperus), were exposed to either rain water or 0.001 M sulphuric acid solution, similar to acid rain in pH. Spectra obtained at the Mid IR beamline and the data obtained from the X-ray Absorption Near Edge Spectroscopy (XANES) were compared for these samples to see the effect of the acid rain-like soluÂŹtion on the silk proteins. No conclusive evidence from the data is present to suggest that the acid rain solution had an effect on the protein structures of either type of spider silk.La soie dâaraignĂ©e est Ă la fois robuste et flexible pour sa taille et son poids.[1] Ces propriĂ©tĂ©s ont piquĂ© la curiositĂ© de dĂ©terminer la structure des protĂ©ines des fibres de soie qui pourrait permettre Ă©ventuelleÂŹment la production des soies synthĂ©tiques.[2] Cette Ă©tude compare les spectres mi- infrarouges (Mi IR) de soie de cinq espĂšces diffĂ©rentes dâaraignĂ©e afin de trouver des similitudes entre les espĂšces et les genres de toiles. Les rĂ©sultats dĂ©montrent que les spectres mi- infrarouges de tout type de soie dâaraignĂ©e Ă©tudiĂ© sont similaires, prĂ©sentant des apogĂ©es de protĂ©ines dans les rĂ©gions de lâAmide I et II. Afin dâĂ©tudier les effets environnementaux dâune solution acide sur la structure de la protĂ©ÂŹine de soie, la soie de deux des cinq espĂšces, le orbe tisserand noir et jaune (Argiope aurantia) et la veuve noire (Latrodectus Hesperus), ont Ă©tĂ© expoÂŹsĂ© soit Ă la pluie naturelle soit Ă une solution dâacide sulfurique 0.001 M qui est proche au pH de la pluie acide. Les spectres obtenus Ă lâonde dirigĂ©e Mi IR et les donnĂ©es obtenues de lâabsorption de la radiÂŹographie prĂšs du seuil de la spectroscopie (ARSS) ont Ă©tĂ© comparĂ©s de ces Ă©chantillons afin de conÂŹstater lâeffet de la solution dâacide sulfurique sur des protĂ©ines de soie. Il nây avait aucune preuve probante des donnĂ©es suggĂ©rant que la solution dâacide sulfurique avait un effet sur la structure des protĂ©ines de soie des araignĂ©es Ă©tudiĂ©
'Family comes in all forms, blood or not': disrupting dominant narratives around the patriarchal nuclear family
After nearly 25 years of democracy, lives of young South Africans are
still profoundly shaped by the legacies of apartheid. This paper
considers how these differences are produced, maintained and
disrupted through an exploration of changing narratives
developed by a small group of South African pre-service teachers,
with a particular focus on the narratives developed around
discourses of fatherhood generally and absent fathers in
particular. We draw on interviews conducted with three students
in which we discussed their digital stories and literature reviews.
In this paper, we draw attention to the limitations of digital
storytelling and the risks such autobiographical storytelling
presents of perpetuating dominant narratives that maintain and
reproduce historical inequalities. At the same time, in highlighting
ways in which this risk might be confronted, the paper also aims
to show the possibilities in which these dominant narratives may
be challenged.IBS
Serological profile of foot-and-mouth disease in wildlife populations of West and Central Africa with special reference to Syncerus caffer subspecies
The role which West and Central African wildlife populations might play in the transmission dynamics of FMD is not known nor have studies been performed in order to assess the distribution and prevalence of FMD in wild animal species inhabiting those specific regions of Africa. This study reports the FMD serological profile extracted from samples (nâ=â696) collected from wildlife of West and Central Africa between 1999 and 2003. An overall prevalence of FMDV NSP reactive sera of 31.0% (216/696) was estimated, where a significant difference in seropositivity (pâ=â0.000) was reported for buffalo (64.8%) as opposed to other wild animal species tested (17.8%). Different levels of exposure to the FMDV resulted for each of the buffalo subspecies sampled (p = 0.031): 68.4%, 50.0% and 0% for Nile Buffalo, West African Buffalo and African Forest Buffalo, respectively. The characterisation of the FMDV serotypes tested for buffalo found presence of antibodies against all the six FMDV serotypes tested, although high estimates for type O and SAT 3 were reported for Central Africa. Different patterns of reaction to the six FMDV serotypes tested were recorded, from sera only positive for a single serotype to multiple reactivities. The results confirmed that FMDV circulates in wild ruminants populating both West and Central Africa rangelands and in particular in buffalo, also suggesting that multiple FMDV serotypes might be involved with type O, SAT 2 and SAT 1 being dominant. Differences in serotype and spill-over risk between wildlife and livestock likely reflect regional geography, historical circulation and differing trade and livestock systems
Frontal Non-Invasive Neurostimulation Modulates Antisaccade Preparation in Non-Human Primates
A combination of oculometric measurements, invasive electrophysiological recordings and microstimulation have proven instrumental to study the role of the Frontal Eye Field (FEF) in saccadic activity. We hereby gauged the ability of a non-invasive neurostimulation technology, Transcranial Magnetic Stimulation (TMS), to causally interfere with frontal activity in two macaque rhesus monkeys trained to perform a saccadic antisaccade task. We show that online single pulse TMS significantly modulated antisaccade latencies. Such effects proved dependent on TMS site (effects on FEF but not on an actively stimulated control site), TMS modality (present under active but not sham TMS on the FEF area), TMS intensity (intensities of at least 40% of the TMS machine maximal output required), TMS timing (more robust for pulses delivered at 150 ms than at 100 post target onset) and visual hemifield (relative latency decreases mainly for ipsilateral AS). Our results demonstrate the feasibility of using TMS to causally modulate antisaccade-associated computations in the non-human primate brain and support the use of this approach in monkeys to study brain function and its non-invasive neuromodulation for exploratory and therapeutic purposes
Reconstruction of the Transmission History of RNA Virus Outbreaks Using Full Genome Sequences: Foot-and-Mouth Disease Virus in Bulgaria in 2011
<div><p>Improvements to sequencing protocols and the development of computational phylogenetics have opened up opportunities to study the rapid evolution of RNA viruses in real time. In practical terms, these results can be combined with field data in order to reconstruct spatiotemporal scenarios that describe the origin and transmission pathways of viruses during an epidemic. In the case of notifiable diseases, such as foot-and-mouth disease (FMD), these analyses provide important insights into the epidemiology of field outbreaks that can support disease control programmes. This study reconstructs the origin and transmission history of the FMD outbreaks which occurred during 2011 in Burgas Province, Bulgaria, a country that had been previously FMD-free-without-vaccination since 1996. Nineteen full genome sequences (FGS) of FMD virus (FMDV) were generated and analysed, including eight representative viruses from all of the virus-positive outbreaks of the disease in the country and 11 closely-related contemporary viruses from countries in the region where FMD is endemic (Turkey and Israel). All Bulgarian sequences shared a single putative common ancestor which was closely related to the index case identified in wild boar. The closest relative from outside of Bulgaria was a FMDV collected during 2010 in Bursa (Anatolia, Turkey). Within Bulgaria, two discrete genetic clusters were detected that corresponded to two episodes of outbreaks that occurred during January and March-April 2011. The number of nucleotide substitutions that were present between, and within, these separate clusters provided evidence that undetected FMDV infection had occurred. These conclusions are supported by laboratory data that subsequently identified three additional FMDV-infected livestock premises by serosurveillance, as well as a number of antibody positive wild boar on both sides of the border with Turkish Thrace. This study highlights how FGS analysis can be used as an effective on-the-spot tool to support and help direct epidemiological investigations of field outbreaks.</p> </div
Mass Mortality of Adult Male Subantarctic Fur Seals: Are Alien Mice the Culprits?
Background: Mass mortalities of marine mammals due to infectious agents are increasingly reported. However, in contrast to previous die-offs, which were indiscriminate with respect to sex and age, here we report a land-based mass mortality of Subantarctic fur seals with apparent exclusivity to adult males. An infectious agent with a male-predilection is the most plausible explanation for this die-off. Although pathogens with gender-biased transmission and pathologies are unusual, rodents are known sources of male-biased infectious agents and the invasive Mus musculus house mouse, occurs in seal rookeries. Methodology / Principal Findings: Molecular screening for male-biased pathogens in this potential rodent reservoir host revealed the absence of Cardiovirus and Leptospirosis genomes in heart and kidney samples, respectively, but identified a novel Streptococcus species with 30 % prevalence in mouse kidneys. Conclusions / Significance: Inter-species transmission through environmental contamination with this novel bacterium, whose congenerics display male-bias and have links to infirmity in seals and terrestrial mammals (including humans)
Altered Error Processing following Vascular Thalamic Damage: Evidence from an Antisaccade Task
Event-related potentials (ERP) research has identified a negative deflection within about 100 to 150 ms after an erroneous response â the error-related negativity (ERN) - as a correlate of awareness-independent error processing. The short latency suggests an internal error monitoring system acting rapidly based on central information such as an efference copy signal. Studies on monkeys and humans have identified the thalamus as an important relay station for efference copy signals of ongoing saccades. The present study investigated error processing on an antisaccade task with ERPs in six patients with focal vascular damage to the thalamus and 28 control subjects. ERN amplitudes were significantly reduced in the patients, with the strongest ERN attenuation being observed in two patients with right mediodorsal and ventrolateral and bilateral ventrolateral damage, respectively. Although the number of errors was significantly higher in the thalamic lesion patients, the degree of ERN attenuation did not correlate with the error rate in the patients. The present data underline the role of the thalamus for the online monitoring of saccadic eye movements, albeit not providing unequivocal evidence in favour of an exclusive role of a particular thalamic site being involved in performance monitoring. By relaying saccade-related efference copy signals, the thalamus appears to enable fast error processing. Furthermore early error processing based on internal information may contribute to error awareness which was reduced in the patients
Risk Prediction for Acute Kidney Injury in Acute Medical Admissions in the UK
Background Acute Kidney Injury (AKI) is associated with adverse outcomes; identifying patients who are at risk of developing AKI in hospital may lead to targeted prevention. This approach is advocated in national guidelines but is not well studied in acutely unwell medical patients. We therefore aimed to undertake a UK-wide study in acute medical units (AMUs) with the following aims: to define the proportion of acutely unwell medical patients who develop hospital-acquired AKI (hAKI); to determine risk factors associated with the development of hAKI; and to assess the feasibility of using these risk factors to develop an AKI risk prediction score. Methods In September 2016, a prospective multicentre cohort study across 72 UK AMUs was undertaken. Data were collected from all patients who presented over a 24-hour period. Chronic dialysis, community-acquired AKI (cAKI) and those with fewer than two creatinine measurements were subsequently excluded. The primary outcome was the development of h-AKI. Results 2,446 individuals were admitted to the AMUs of the 72 participating centres. 384 patients (16%) sustained AKI of whom 287 (75%) were cAKI and 97 (25%) were hAKI. After exclusions, 1,235 participants remained in whom chronic kidney disease (OR 3.08, 95% CI 1.96-4.83), diuretic prescription (OR 2.33, 95% CI 1.5-3.65), a lower haemoglobin concentration and an elevated serum bilirubin were independently associated with development of hAKI. Multivariable model discrimination was moderate (c-statistic 0.75), and this did not support the development of a robust clinical risk prediction score. Mortality was higher in those with hAKI (adjusted OR 5.22; 95% CI 2.23-12.20). Conclusion AKI in AMUs is common and associated with worse outcomes, with the majority of cases community acquired. The smaller proportion of hAKI cases, only moderate discrimination of prognostic risk factor modelling and the resource implications of widespread application of an AKI clinical risk score across all AMU admissions suggests that this approach is not currently justified. More targeted risk assessment or automated methods of calculating individual risk may be more appropriate alternatives
Digital storytelling as a tool for teaching: Perceptions of pre-service teachers
It has been shown that teachers are reluctant to use technology despite the South African (SA) governmentâs huge expenditure on technological equipment. This might be the result of teachers being unable to select appropriate technology that will yield positive learning outcomes as well as being ill-equipped to integrate technology into their pedagogy. To this end, pre-service teachers at a University were trained on how to integrate digital storytelling (DST) effectively into their teaching. The aim of this study is to gain insight into the potential benefits of DST for teaching and learning and to determine factors that may prevent pre-service teachersâ uptake of DST during in-service practice. This is a qualitative study in which fifty pre-service teachers were divided into five groups for focus group interviews. Data were analysed, and the results show that pre- service teachers perceived DST to be beneficial in the classroom as it has the potential to (i) motivate and engage learners, (ii) promote voice/self-expression, and (iii) promote collaborative learning and acquisition of multiple skills. Pre-service teachers are of the opinion that a lack of resources, self-confidence and time owing to restrictive curricula may prevent uptake of DST during in-service teaching. It was recommended that school stakeholders create a balance between intrinsic and extrinsic factors that will promote the adoption and integration of DST into teaching. Also, the education institution concerned strives to balance all three strands of knowledge: technology, pedagogy and content
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