601 research outputs found
Are conservation actions reducing the threat to India's vulture populations?
Research Communications.-- et al.Veterinary use of the non-steroidal anti-inflammatory drug, diclofenac is responsible for the population collapse of resident vulture species in India. Conservation efforts, including a ban on veterinary diclofenac and the identification of a vulture-safe alternative (meloxicam), were introduced in 2006 in order to address the threat. Sampling of domesticated ungulate carcasses available to vultures in India was undertaken in three surveys prior to, around the time of, and 1-2 years after the ban in order to quantify the prevalence of diclofenac and meloxicam residues. A total of 1445, 1488 and 1251 liver tissue samples were collected from nine states and analysed with a validated LC-ESI/MS methodology. Overall diclofenac prevalence levels declined by almost a half over the three surveys, and there was an increase in meloxicam prevalence between the second and third surveys, although some states revealed little change. These surveys indicate that two of the key conservation actions to counter the threat faced by vultures - banning veterinary diclofenac and promoting meloxicam as a safe alternative - are beginning to take effect. However, because only a small proportion of diclofenac-contaminated carcasses is sufficient to cause vulture population declines, further efforts are needed to eliminate diclofenac from the food supply of India's vultures.The research was funded by the UK Government’s Darwin Initiative programme and by the
Royal Society for the Protection of Birds, UK.Peer Reviewe
Recommended from our members
Aging is associated with positive responding to neutral information but reduced recovery from negative information
Studies on aging and emotion suggest an increase in reported positive affect, a processing bias of positive over negative information, as well as increasingly adaptive regulation in response to negative events with advancing age. These findings imply that older individuals evaluate information differently, resulting in lowered reactivity to, and/or faster recovery from, negative information, while maintaining more positive responding to positive information. We examined this hypothesis in an ongoing study on Midlife in the US (MIDUS II) where emotional reactivity and recovery were assessed in a large number of respondents (N = 159) from a wide age range (36–84 years). We recorded eye-blink startle magnitudes and corrugator activity during and after the presentation of positive, neutral and negative pictures. The most robust age effect was found in response to neutral stimuli, where increasing age is associated with a decreased corrugator and eyeblink startle response to neutral stimuli. These data suggest that an age-related positivity effect does not essentially alter the response to emotion-laden information, but is reflected in a more positive interpretation of affectively ambiguous information. Furthermore, older women showed reduced corrugator recovery from negative pictures relative to the younger women and men, suggesting that an age-related prioritization of well-being is not necessarily reflected in adaptive regulation of negative affect
Refractory chronic GVHD emerging after splenectomy in a marrow transplant recipient with accelerated phase CML
We report a 39-year-old female patient who underwent HLA-identical sibling allogeneic BMT for CML in accelerated phase. Severe pancytopenia refractory to G-CSF associated with progressive splenomegaly and RBC/ platelet transfusion dependency were present from day + 60 after BMT. MRD assessed by FISH and RT-PCR multiplex for BCR-ABL rearrangement was negative, and complete chimerism was documented by VNTR on days + 100, + 180, + 360 and 2 years after BMT. Splenectomy was performed on day + 225 and pancytopenia resolved but chronic extensive graft-versus-host disease developed, with hepatic cholestasis, diffuse scleroderma and sicca-like syndrome. She was sequentially and progressively treated with different immunosuppressive therapy combinations with no clear benefit. On day + 940, she presented with infection over the previously present ulcers on both limbs, which culminated in septic shock and death on day + 1041. We conclude that, although splenectomy may reverse poor graft function after allogeneic BMT, hyposplenism may trigger or worsen chronic extensive GVHD leading to increased morbidity and mortality.Hosp São Paulo, São Paulo, BrazilHosp São Paulo, São Paulo, BrazilWeb of Scienc
Pollution, habitat loss, fishing and climate change as critical threats to penguins
Cumulative human impacts across the world’s oceans are considerable. We therefore examined a single model taxonomic group, the penguins (Spheniscidae), to explore how marine species and communities might be at risk of decline or extinction in the southern hemisphere. We sought to determine the most important threats to penguins and to suggest means to mitigate these threats. Our review has relevance to other taxonomic groups in the southern hemisphere and in northern latitudes, where human impacts are greater. Our review was based on an expert assessment and literature review of all 18 penguin species; 49 scientists contributed to the process. For each penguin species, we considered their range and distribution, population trends, and main anthropogenic threats over the past approximately 250 years. These threats were harvesting adults for oil, skin, and feathers and as bait for crab and rock lobster fisheries; harvesting of eggs; terrestrial habitat degradation; marine pollution; fisheries bycatch and resource competition; environmental variability and climate change; and toxic algal poisoning and disease. Habitat loss, pollution, and fishing, all factors humans can readily mitigate, remain the primary threats for penguin species. Their future resilience to further climate change impacts will almost certainly depend on addressing current threats to existing habitat degradation on land and at sea. We suggest protection of breeding habitat, linked to the designation of appropriately scaled marine reserves, including in the High Seas, will be critical for the future conservation of penguins. However, large-scale conservation zones are not always practical or politically feasible and other ecosystem-based management methods that include spatial zoning, bycatch mitigation, and robust harvest control must be developed to maintain marine biodiversity and ensure that ecosystem functioning is maintained across a variety of scales.Los impactos humanos acumulativos a lo largo de los océanos del planeta son considerables. Por eso examinamos un solo modelo de grupo taxonómico, los pingüinos (Sphenischidae), para explorar cómo las especies y las comunidades marinas pueden estar en riesgo de disminuir o de extinguirse en el hemisferio sur. Buscamos determinar la amenaza más importante para los pingüinos y sugerir métodos para mitigar estas amenazas. Nuestra revisión tiene relevancia para otros grupos taxonómicos en el hemisferio sur y en las latitudes norteñas, donde los impactos humanos son mayores. Nuestra revisión se basó en una evaluación experta y una revisión de literaratura de las 18 especies de pingüinos; 49 científicos contribuyeron al proceso. Para cada especie de pingüino, consideramos su rango y distribución, tendencias poblacionales y las principales amenazas antropogénicas en aproximadamente los últimos 250 años. Estas amenazas fueron la captura de adultos para obtener aceite, piel y plumas y el uso como carnada para la pesca de cangrejos y langostas: la recolección de huevos; la degradación del hábitat terrestre; la contaminación marina; la pesca accesoria y la competencia por recursos; la variabilidad ambiental y el cambio climático; y el envenenamiento por algas tóxicas y enfermedades. La pérdida de hábitat, la contaminación y la pesca, todos factores que los humanos pueden mitigar, siguen siendo las amenazas principales para las especies de pingüinos. Su resiliencia futura a más impactos por cambio climático dependerá certeramente de que nos enfoquemos en las amenazas actuales a la degradación de hábitats existentes en tierra y en el mar. Sugerimos que la protección de hábitats de reproducción, en conjunto con la designación de reservas marinas de escala apropiada, incluyendo alta mar, será crítica para la conservación futura de los pingüinos. Sin embargo, las zonas de conservación a gran escala no son siempre prácticas o políticamente viables, y otros métodos de manejo basados en ecosistemas que incluyen la zonificación espacial, la mitigación de captura accesoria, y el control fuerte de captura deben desarrollarse para mantener la biodiversidad marina y asegurar que el funcionamiento de los ecosistemas se mantenga a lo largo de una variedad de escalas.Fil: Trathan, Phil N.. British Antartic Survey; Reino UnidoFil: Garcia Borboroglu, Jorge Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Boersma, P. Dee. University of Washington; Estados UnidosFil: Bost, Charles André. Centre d´Etudes Biologiques de Chizé; FranciaFil: Crawford, Robert J. M.. Department of Environmental Affairs; SudáfricaFil: Crossin, Glenn T.. Dalhousie University Halifax; CanadáFil: Cuthbert, Richard. Royal Society for the Protection of Birds; Reino UnidoFil: Dann, Peter. Phillip Island Nature Parks; AustraliaFil: Davis, Lloyd Spencer. University Of Otago; Nueva ZelandaFil: de la Puente, Santiago. Universidad Cayetano Heredia; PerúFil: Ellenberg, Ursula. University Of Otago; Nueva ZelandaFil: Lynch, Heather J.. Stony Brook University; Estados UnidosFil: Mattern, Thomas. University Of Otago; Nueva ZelandaFil: Pütz, Klemens. Antarctic Research Trust; AlemaniaFil: Seddon, Philip J.. University Of Otago; Nueva ZelandaFil: Trivelpiece, Wayne. Southwest Fisheries Science Center; Estados UnidosFil: Wienecke, Bárbara. Australian Antarctic Division; Australi
Evolutionary factors affecting the cross-species utility of newly developed microsatellite markers in seabirds
Microsatellite loci are ideal for testing hypotheses relating to genetic segregation at fine spatio-temporal scales. They are also conserved among closely related species, making them potentially useful for clarifying interspecific relationships between recently diverged taxa. However, mutations at primer binding sites may lead to increased non-amplification, or disruptions that may lead to decreased polymorphism in non-target species. Furthermore, high mutation rates and constraints on allele size may also lead, with evolutionary time, to an increase in convergently evolved allele size classes, biasing measures of interspecific genetic differentiation. Here, we used next-generation sequencing to develop microsatellite markers from a shotgun genome sequence of the sub-Antarctic seabird, the thin-billed prion (Pachyptila belcheri), that we tested for cross-species amplification in other Pachyptila and related sub-Antarctic species. We found that heterozygosity decreased and the proportion of non-amplifying loci increased with phylogenetic distance from the target species. Surprisingly, we found that species trees estimated from interspecific FST provided better approximations of mtDNA relationships among the studied species than those estimated using DC, even though FST was more affected by null alleles. We observed a significantly non-linear second order polynomial relationship between microsatellite and mtDNA distances. We propose that the loss of linearity with increasing mtDNA distance stems from an increasing proportion of homoplastic allele size classes that are identical in state, but not identical by descent. Therefore, despite high cross-species amplification success and high polymorphism among the closely related Pachyptila species, we caution against the use of microsatellites in phylogenetic inference among distantly related taxa
The Design and Construction of a UHV Test System to Evaluate A Magnetron Pump-Gauge (Part B)
Second project report of two. Part A is available at http://hdl.handle.net/11375/17551 The design, construction, and initial operation of an ultra high vacuum testing system was undertaken. The final UHV system is equipped with a residual gas analyser (RGA). The system was used to test a National Research Council of Canada magnetron pump-gauge. The pumping action of the device was adequate with speeds of litres/second for hydrogen and other chemically active species. A speed of ≃0.3 L/S was measured for methane (CH₄). The pressure measuring capabilities of this particular pump may be in question due to the presence of surface leakage currents. ThesisMaster of Engineering (ME
Exploiting knowledge of mesenchymal stromal cells in vivo for bone disease therapy development
This thesis aims to demonstrate how understanding of the nature of MSCs in vivo can be used to guide bone disease therapy development. It first address the unpredictable MSC content of bone marrow (BM) aspirates used for therapy; then examines MSC enrichment using clinical grade immunomagnetic cell selection. Induction of osteogenesis was subsequently explored; by examining an induced membrane (IM) used for bone regeneration. Finally the potential of a janus kinase (JAK) inhibitor to block osteogenesis was assessed, by studying its effect on MSCs in vitro.
Flow cytometry was used to enumerate cells expressing a CD45-/low CD271+ phenotype in BM aspirate and this was compared to colony forming unit fibroblast (CFU-F) content. MSCs were enriched from BM, enzymatically treated femoral heads (FH) and intramedullary canal aspirates and enumerated. The composition morphology, MSC content and differentiation potential of IM was compared to periosteum. The potential effects of JAK inhibition on MSC colony formation, expansion and differentiation potential were examined.
The concentration of cells expressing a CD45-/low CD271+ phenotype strongly correlated with CFU-F concentration (R=0.812, p<0.001). Immunomagnetic cell selection resulted in an increase in the proportion of MSCs in BM, FH and intramedullary canal aspirates by 204, 14.1 and 291-fold respectively. The regenerative potential of periosteum and IM were comparable. JAK inhibition did not affect MSC growth, osteogenesis or chondrogenesis but caused an increase in adipogenesis at concentrations ≥100nM compared to controls (1.38 fold, p=0.041).
Flow cytometry may be used to rapidly and accurately predict the MSC content of BM. Clinical grade immunomagnetic selection can substantially increase the purity of MSCs from bone cavities. The similarity, in terms of regenerative potential, of periosteum and IM gives insight into its use for bone regeneration. JAK inhibition did not affect in vitro osteogenesis but has potential to affect in vivo osteogenesis through stimulation of adipogenesis
The Design and Construction of a Surface Analysis Station (Part A)
One of two project reports. Part B is available at http://hdl.handle.net/11375/17552 The design, construction, and initial operation of a surface analysis station were undertaken. The final UHV system is equipped for ion surface scattering, low energy electron diffraction, Auger analysis, secondary ion mass spectroscopy and residual gas analysis. The main goal of this project was the preliminary operation of the ion surface scattering equipment. A complete beam transport system was constructed utilizing an Einzel lens and electrostatic quadroles. The ion surface scattering was effected through the use of a time-of-flight (TOF) technique to obtain an energy spectrum of particles backscattered from a target surface. The TOF spectrum and subsequent energy spectrum were for 5.1 keV hydrogen ions incident on a practical silver target. ThesisMaster of Engineering (ME
Intermediate predator naïveté and sex-skewed vulnerability predict the impact of an invasive higher predator
The spread of invasive species continues to reduce biodiversity across all regions and habitat types globally. However, invader impact prediction can be nebulous, and approaches often fail to integrate coupled direct and indirect invader effects. Here, we examine the ecological impacts of an invasive higher predator on lower trophic groups, further developing methodologies to more holistically quantify invader impact. We employ functional response (FR, resource use under different densities) and prey switching experiments to examine the trait- and density-mediated impacts of the invasive mosquitofish Gambusia affinis on an endemic intermediate predator Lovenula raynerae (Copepoda). Lovenula raynerae effectively consumed larval mosquitoes, but was naïve to mosquitofish cues, with attack rates and handling times of the intermediate predator unaffected by mosquitofish cue-treated water. Mosquitofish did not switch between male and female prey, consistently displaying a strong preference for female copepods. We thus demonstrate a lack of risk-reduction activity in the presence of invasive fish by L. raynerae and, in turn, high susceptibility of such intermediate trophic groups to invader impact. Further, we show that mosquitofish demonstrate sex-skewed predator selectivity towards intermediate predators of mosquito larvae, which may affect predator population demographics and, perversely, increase disease vector proliferations. We advocate the utility of FRs and prey switching combined to holistically quantify invasive species impact potential on native organisms at multiple trophic levels
Climate-groundwater dynamics inferred from GRACE and the role of hydraulic memory
Groundwater is the largest store of freshwater on Earth after the cryosphere and provides a substantial proportion of the water used for domestic, irrigation and industrial purposes. Knowledge of this essential resource remains incomplete, in part, because of observational challenges of scale and accessibility. Here we examine a 14-year period (2002–2016) of GRACE observations to investigate climate-groundwater dynamics of 14 tropical and sub-tropical aquifers selected from WHYMAP's 37 large aquifer systems of the world. GRACE-derived changes in groundwater storage resolved using GRACE JPL Mascons and the CLM Land Surface Model are related to precipitation time series and regional-scale hydrogeology. We show that aquifers in dryland environments exhibit long-term hydraulic memory through a strong correlation between groundwater storage changes and annual precipitation anomalies integrated over the time series; aquifers in humid environments show short-term memory through strong correlation with monthly precipitation. This classification is consistent with estimates of Groundwater Response Times calculated from the hydrogeological properties of each system, with long (short) hydraulic memory associated with slow (rapid) response times. The results suggest that groundwater systems in dryland environments may be less sensitive to seasonal climate variability but vulnerable to long-term trends from which they will be slow to recover. In contrast, aquifers in humid regions may be more sensitive to seasonal climate disturbances such as ENSO-related drought but may also be relatively quick to recover. Exceptions to this general pattern are traced to human interventions through groundwater abstraction. Hydraulic memory is an important factor in the management of groundwater resources, particularly under climate change
- …
