Sophorolipid biosurfactants: Possible uses as antibacterial and antibiofilm agent.

Biosurfactants are amphipathic, surface-active molecules of microbial origin which accumulate at interfaces reducing interfacial tension and leading to the formation of aggregated micellular structures in solution. Some biosurfactants have been reported to have antimicrobial properties, the ability to prevent adhesion and to disrupt biofilm formation. We investigated antimicrobial properties and biofilm disruption using sophorolipids at different concentrations. Growth of Gram negative Cupriavidus necator ATCC 17699 and Gram positive Bacillus subtilis BBK006 were inhibited by sophorolipids at concentrations of 5% v/v with a bactericidal effect. Sophorolipids (5% v/v) were also able to disrupt biofilms formed by single and mixed cultures of B. subtilis BBK006 and Staphylococcus aureus ATCC 9144 under static and flow conditions, as was observed by scanning electron microscopy. The results indicated that sophorolipids may be promising compounds for use in biomedical application as adjuvants to other antimicrobial against some pathogens through inhibition of growth and/or biofilm disruption

Backpack-mounted satellite transmitters do not affect reproductive performance in a migratory bustard

Backpack-mounted satellite transmitters (PTTs) are used extensively in the study of avian habitat use and of the movements and demography of medium- to large-bodied species, but can affect individuals’ performance and fitness. Transparent assessment of potential transmitter effects is important for both ethical accountability and confidence in, or adjustment to, life history parameter estimates. We assessed the influence of transmitters on seven reproductive parameters in Asian houbara Chlamydotis macqueenii, comparing 114 nests of 38 females carrying PTTs to 184 nests of untagged birds (non-PTT) over seven breeding seasons (2012‒2018) in Uzbekistan. There was no evidence of any influence of PTTs on: lay date (non-PTT x̅ = 91.7 Julian day ± 12.3 SD; PTT x̅ = 95.1 Julian day ± 15.7 SD); clutch size (non-PTT x̅ = 3.30 ± 0.68 SD; PTT x̅ = 3.25 ± 0.65 SD); mean egg weight at laying (non-PTT x̅ = 66.1g ± 5.4 SD; PTT x̅ = 66.4g ± 5.4 SD); nest success (non-PTT x̅ = 57.08% ± 4.3 SE; PTT x̅ = 58.24% ± 4.5 SE for nests started 2 April); egg hatchability (non-PTT x̅ = 88.3% ± 2.2 SE; PTT x̅ = 88.3% ± 2.6 SE); or chick survival to fledging from broods that had at least one surviving chick (non-PTT x̅ = 63.4% ± 4.2 SE; PTT x̅= 64.4% ± 4.7 SE). High nesting propensity (97.3% year-1 ± 1.9% SE) of tagged birds indicated minimal PTT effect on breeding probability. These findings show harness-mounted transmitters can give unbiased measures of demographic parameters of this species, and are relevant to other large-bodied, cursorial, ground-nesting birds of open habitats, particularly other bustards

Anti-neutrophil cytoplasmic antibodies:Current diagnostic and pathophysiological potential

Rapidly progressive glomerulonephritis (RPGN) is a clinical syndrome characterized by rapid deterioration of renal function occurring within days or weeks together with signs of glomerulonephritis, that is, proteinuria and hematuria with cellular casts. The syndrome is, in many cases, histopathologically manifested as fibrinoid necrosis of the capillary wall with extracapillary proliferation and crescent formation [1]. This so-called necrotizing crescentic glomerulonephritis (NCGN) is seen in 5 to 15% of renal biopsies in most series [1–3]. Although it is infrequent, the importance of the condition is illustrated by the fact that most cases of NCGN, if left untreated, develop renal failure within days or weeks [1]. Based on immunohistopathology NCGN can be subdivided into three distinct categories. The first one, occurring in 2 to 20% of the cases and characterized by linear staining of the glomerular capillary wall for immunoglobulin and complement, has classically been described as anti-glomerular basement membrane (GBM) disease. It is associated with autoantibodies to structural antigens of the GBM, in particular to the first globular noncollagen domain of collagen type IV [4]. The antibodies are considered of pathogenetic significance. The second category, comprising 15 to 50% of cases, is characterized by granular deposits of immunoglobulin and complement suggesting that immune complexes are pathogenetically involved. This type occurs in conjunction with systemic autoimmune diseases such as lupus erythematosus, in cases of post-infectious glomerulonephritis, IgA nephropathy or Henoch-Schönlein purpura, or as an idiopathic variety. The third group of NCGN, occurring in 40 to 80%, demonstrates only a few or no immune deposits and is designated as pauci-immune NCGN [1–3, 5, 6]. Pauci-immune NCGN occurs as part of Wegener's granulomatosis (WG) or related conditions, or without systemic vasculitis (idiopathic NCGN). The pathophysiology of this pauci-immune type of NCGN has not been elucidated. Within the last decade, however, it has been recognized that the condition is associated with autoantibodies to cytoplasmic components of neutrophils (anti-neutrophil cytoplasmic antibodies or ANCA).ANCA were first described in 1982 by Davies et al in a few patients with segmental necrotizing glomerulonephritis [7]. Only in 1985 did it become apparent that ANCA are a sensitive and specific marker for Wegener's granulomatosis (WG) [8]. Later on, ANCA were described in patients with microscopic polyarteritis [9]. Falk and Jennette, in 1988, showed that ANCA are also associated with the idiopathic form of pauci-immune NCGN [10]. These data have now been confirmed by many groups and support the view that ANCA-associated glomerulonephritis and vasculitis is, indeed, a distinct disease category. A number of studies, in addition, have suggested that ANCA are involved in the pathophysiology of the aforementioned disorders. As ANCA, however, have recently also been detected in a wide range of inflammatory and infectious conditions, a critical reappraisal of the diagnostic significance of ANCA-testing seems justified.In this review we will evaluate the current state of ANCA-testing as well as elaborate on the pathophysiological role of the autoantibodies in necrotizing glomerulonephritis and vasculitis. Data presented recently at the Fifth International Workshop on ANCA, held in Cambridge, United Kingdom, will be included [11]. As such, it adds to previous reviews on ANCA that were published following the Second [12], Third [13], and Fourth [14] Workshops on ANCA

Don’t forget the porpoise: acoustic monitoring reveals fine scale temporal variation between bottlenose dolphin and harbour porpoise in Cardigan Bay SAC

Populations of bottlenose dolphin and harbour porpoise inhabit Cardigan Bay, which was designated a Special Area of Conservation (SAC), with bottlenose dolphin listed as a primary feature for its conservation status. Understanding the abundance, distribution and habitat use of species is fundamental for conservation and the implementation of management. Bottlenose dolphin and harbour porpoise usage of feeding sites within Cardigan Bay SAC was examined using passive acoustic monitoring. Acoustic detections recorded with calibrated T-PODs (acoustic data loggers) indicated harbour porpoise to be present year round and in greater relative abundance than bottlenose dolphin. Fine-scale temporal partitioning between the species occurred at three levels: (1) seasonal differences, consistent between years, with porpoise detections peaking in winter months and dolphin detections in summer months; (2) diel variation, consistent across sites, seasons and years, with porpoise detections highest at night and dolphin detections highest shortly after sunrise; and (3) tidal variation was observed with peak dolphin detections occurring during ebb at the middle of the tidal cycle and before low tide, whereas harbour porpoise detections were highest at slack water, during and after high water with a secondary peak recorded during and after low water. General Additive Models (GAMs) were applied to better understand the effects of each covariate. The reported abundance and distribution of the two species, along with the temporal variation observed, have implications for the design and management of protected areas. Currently, in the UK, no SACs have been formally designated for harbour porpoise while three exist for bottlenose dolphins. Here, we demonstrate a need for increased protection and species-specific mitigation measures for harbour porpoise

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Using citizen science to better understand Risso’s dolphin (Grampus griseus) presence in northeast Scotland and the Northern Isles

There is no current population estimate for Risso’s dolphin (Grampus griseus) in Scottish waters and their distribution in the northeast of Scotland and the Northern Isles is poorly documented. Using a combination of citizen science and historical sightings data, photographs of Risso’s dolphins from northeast Scotland and the Northern Isles were gathered to gain an indication of the presence of the species in this region. A review of all available sighting records from as early as 1933 (n = 1,904 records), showed a historical presence of Risso’s dolphins in the study locations, with a notable increase in sightings reports over time and with higher numbers of sightings reported from July-September. Collation of photographs (n = 1,884) taken by members of the public and researchers facilitated the establishment of two photo-identification catalogues for Northeast Scotland and Orkney (n = 112 individuals) and for Shetland (n = 47 individuals) respectively. Mother/calf pairs were recorded between April and November. Repeated recaptures of identifiable animals throughout the study area provided the first evidence of inter/intra-annual site fidelity. The combined datasets demonstrate the potential importance of inshore coastal waters in northeast Scotland, Orkney, and Shetland as critical habitat for Risso’s dolphins. Recommendations are made for ongoing monitoring studies to inform the protection of Risso’s dolphins in Scottish waters

Earlier snowmelt may lead to late season declines in plant productivity and carbon sequestration in Arctic tundra ecosystems

Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June and July, but with lower net carbon sequestration and lower GPP in August. Although higher evapotranspiration (ET) can result in soil drying with the progression of the summer, we did not find significantly lower soil moisture with earlier snowmelt, nor evidence that water stress affected GPP in the late growing season. Our results suggest that the expected increased CO2 sequestration arising from Arctic warming and the associated increase in growing season length may not materialize if tundra ecosystems are not able to continue sequestering CO2 later in the season

The consolidated European synthesis of CH4 and N2O emissions for the European Union and United Kingdom : 1990-2017

Reliable quantification of the sources and sinks of greenhouse gases, together with trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Paris Agreement. This study provides a consolidated synthesis of CH4 and N2O emissions with consistently derived state-of-the-art bottom-up (BU) and top-down (TD) data sources for the European Union and UK (EU27 C UK). We integrate recent emission inventory data, ecosystem process-based model results and inverse modeling estimates over the period 1990-2017. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported to the UN climate convention UNFCCC secretariat in 2019. For uncertainties, we used for NGHGIs the standard deviation obtained by varying parameters of inventory calculations, reported by the member states (MSs) following the recommendations of the IPCC Guidelines. For atmospheric inversion models (TD) or other inventory datasets (BU), we defined uncertainties from the spread between different model estimates or model-specific uncertainties when reported. In comparing NGHGIs with other approaches, a key source of bias is the activities included, e.g., anthropogenic versus anthropogenic plus natural fluxes. In inversions, the separation between anthropogenic and natural emissions is sensitive to the geospatial prior distribution of emissions. Over the 2011-2015 period, which is the common denominator of data availability between all sources, the anthropogenic BU approaches are directly comparable, reporting mean emissions of 20.8 TgCH(4) yr (-1) (EDGAR v5.0) and 19.0 TgCH(4) yr(-1) (GAINS), consistent with the NGHGI estimates of 18.9 +/- 1.7 TgCH(4) yr(-1). The estimates of TD total inversions give higher emission estimates, as they also include natural emissions. Over the same period regional TD inversions with higher-resolution atmospheric transport models give a mean emission of 28.8 TgCH(4) yr(-1). Coarser-resolution global TD inversions are consistent with regional TD inversions, for global inversions with GOSAT satellite data (23.3 TgCH(4) yr(-1)) and surface network (24.4 TgCH(4) yr (-1)). The magnitude of natural peatland emissions from the JSBACH-HIMMELI model, natural rivers and lakes emissions, and geological sources together account for the gap between NGHGIs and inversions and account for 5.2 TgCH(4) yr(-1). For N2O emissions, over the 2011-2015 period, both BU approaches (EDGAR v5.0 and GAINS) give a mean value of anthropogenic emissions of 0.8 and 0.9 TgN(2)Oyr(-1), respectively, agreeing with the NGHGI data (0.9 0.6 TgN(2)Oyr(-1)). Over the same period, the average of the three total TD global and regional inversions was 1.3 +/- 0.4 and 1.3 +/- 0.1 TgN(2)Oyr(-1), respectively. The TD and BU comparison method defined in this study can be operationalized for future yearly updates for the calculation of CH4 and N2O budgets both at the EU CUK scale and at the national scale.Peer reviewe

Earlier snowmelt may lead to late season declines in plant productivity and carbon sequestration in Arctic tundra ecosystems

Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June and July, but with lower net carbon sequestration and lower GPP in August. Although higher evapotranspiration (ET) can result in soil drying with the progression of the summer, we did not find significantly lower soil moisture with earlier snowmelt, nor evidence that water stress affected GPP in the late growing season. Our results suggest that the expected increased CO2 sequestration arising from Arctic warming and the associated increase in growing season length may not materialize if tundra ecosystems are not able to continue sequestering CO2 later in the season.Peer reviewe