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Maintenance and enhancement of peatland carbon storage is a major policy objective towards meeting greenhouse gas (GHG) targets. Management interventions can influence both the storage capacity and the vulnerability of the stock to climate-change induced increases in drought frequency and severity, and incidence of wildfires. Quantification of these interactions is vital in informing best management practice, but is also challenging, given the ephemeral nature of climatic extremes and the usual paucity of high-quality ground-based observations within an area of interest capable of providing the necessary pre-impact and control data.Following a dry and warm spell in spring 2019, a large wildfire burnt approximately >60 km2 of blanket bog and wet heath within the Flow Country peatlands of Caithness and Sutherland, North Scotland. While the Flow Country is a site of global significance currently under consideration for UNESCO World Heritage Site Status, it has also been substantially modified in places by drainage and notably forestry (670 km2) and is now undergoing rapid and large-scale restoration. Serendipitously, the fire scar impacted the whole range of land-uses and occurred in an area actively used for research, and therefore where some baseline datasets were available.The NERC funded FireBlanket project used this opportunity to investigate how land-uses interacted with wildfire in terms of 1) InSAR-derived “bog breathing” patterns exhibited during the 2018 drought 2) immediate and longer-term effects on vegetation communities 3) export and fate of organic carbon from land to ocean. By understanding how different management strategies of forestry and forest-to-bog restoration influence fire risk and damage, we hope to inform decision-making in the future.Our preliminary results show that in near-natural and restored (drain-blocked) blanket bogs, the drought of 2018 led to a rapid surface compression that maintained near-surface moisture until 2019, in turn reducing the severity of the wildfire. In drained and degraded blanket bogs, this mechanical feedback is absent, due to higher bulk density and differences in vegetation assemblages, notably reduced cover of Sphagnum mosses. In those areas, the 2018 drought led to a rapid and sustained loss of moisture in the upper peat layers, associated with higher burn severity and more pronounced fire damage on vegetation. Furthermore, while DOM concentrations increased post-fire in streams receiving water from all burnt areas compared to unburnt ones, the changes were more pronounced in catchments with man-made drains.Whilst further data processing and analysis is still underway, our study currently suggests that restoration is likely to increase wildfire resilience and reduce wildfire severity. When taking management decisions at the landscape scale, strategic re-wetting around vulnerable areas (e.g. highly degraded or undergoing forest-to-bog management leading to large volumes of brash on the ground) may help reduce the risks of occurrence of large catastrophic wildfires, and help minimise the carbon losses associated with these events.

The flux of terrigenous organic carbon across estuaries is an important and changing component of the global carbon cycle, but it is poorly understood. It has been proposed that estuaries can act either as a transporter of terrestrial dissolved organic carbon (DOC) to the ocean or as a reactor system in which DOC can be buried or transformed into carbon dioxide and released to the atmosphere. However, there is no clear understanding of the factors that drive estuaries to behave in one way or the other. Here we present the results from a study conducted in thirteen British estuaries which drain catchments of diverse land-uses under different hydrological conditions. Our data show that land-use influences the composition of the dissolved organic matter (DOM), the mixing dynamics of DOC and the quantity of DOC exported off the estuaries. Estuaries, whose catchments are less intensively managed and represent more natural ecosystems (average proportion of arable and (sub)-urban land-use ~12 %), contain a higher proportion of biologically-refractory “humic-like” DOM, which is transported conservatively across the salinity gradient. In contrast, estuaries whose catchments are more intensively managed (average proportion of arable and (sub)-urban land-use ~32 %) contain a high fraction of “protein-like” DOM which is transported non-conservatively, and thus suggest the existence of additions and removal processes across the salinity gradient. Furthermore, estuaries with more intensively managed catchments tend to export more DOC to coastal areas than they receive from rivers. Our results indicate that future changes in land-use have the potential to alter aquatic fluxes of terrigenous DOM and the fate of the constituent carbon.

Hadal trenches house distinct ecosystems but we know little about their sources of nutrition or trophic structures. We evaluated megafaunal food web structure and nutritional sources in the Kermadec and Mariana trenches using carbon and nitrogen stable isotope analysis (δ15N and δ13C values) of bulk tissues and proteinaceous individual amino acids (AAs). In the Kermadec Trench, bulk δ15N values ranged from 5.8‰ in trench sediment to 17.5‰ in tissues of the supergiant amphipod, Allicela gigantea. δ15N values of detritivores were much higher than those of sediments (by 7.5‰ more). The δ13C values ranged from −21.4‰ in sediments to −17.3‰ in the brittle star, Ophiolimna sp., and did not co-vary with δ15N values. In the Mariana Trench, only bait-attending fauna and surface sediments were available for analysis. Mariana Trench fishes, amphipods, and sediments had slightly lower δ15N values than those from the Kermadec Trench, possibly because the Mariana Trench lies under more oligotrophic surface waters. We found evidence for multiple food inputs to the system in each trench, namely substantially higher δ15N values in detritivores relative to sediment and high variability in δ13C values. Trophic levels determined from isotopic analysis of individual AAs in the Kermadec Trench ranged from three for detritivores to five for fishes. Source AA δ15N values were variable (range of ~7.0‰ in average δ15N source AA values), with much of this variation occurring in small amphipods. For the other fauna sampled, there was a significant increase in δ15N source AA values with increasing collection depth. This increase could reflect larger amounts of highly microbially reworked organic matter with increasing depth or sporadic input from turbidity flows. Although further sampling across a broader faunal diversity will be required to understand these food webs, our results provide new insights into hadal trophic interactions and suggest that trench food webs are very dynamic.

Understanding the factors that control the growth of heterotrophic organisms is central to predicting food web interactions and biogeochemical cycling within ecosystems. We present a new framework, Geometric Stoichiometry (GS), that unifies the disciplines of Nutritional Geometry (NG) and Ecological Stoichiometry (ES) by extending the equations of ES to incorporate core NG concepts, including macromolecules as currencies and the ability of animals to select foods that balance deficits and excesses of nutrients. The resulting model is used to investigate regulation of consumer growth by dietary protein:carbohydrate ratio. Growth on protein-poor diets is limited by nitrogen. Likewise, we show that growth is also diminished on protein-rich diets and that this can be mechanistically explained by means of a metabolic penalty that arises when animals use protein for energy generation. These penalties, which are incurred when dealing with the costs of producing and excreting toxic nitrogenous waste, have not hitherto been represented in standard ES theory. In order to incorporate GS within ecosystem and biogeochemical models, a new generation of integrated theoretical and experimental studies based on unified concepts of NG and ES is needed, including measurements of food selection, biomass, growth and associated physiology, and involving metabolic penalties.

Antarctic krill inhabit areas of the Southern Ocean that can exceed 4.0°C, yet they preferentially inhabit regions with temperatures of −1.5 to ≤1.5°C. Successful embryonic development and hatching are key to their life cycle, but despite the rapid climatic warming seen across their main spawning areas, the effects of elevated temperatures on embryogenesis, hatching success, and nauplii malformations are unknown. We incubated 24,483 krill embryos in two independent experiments to investigate the hypothesis that temperatures exceeding 1.5°C have a negative impact on hatching success and increase the numbers of malformed nauplii. Field experiments were on krill collected from near the northern, warm limit of their range and embryos incubated soon after capture, while laboratory experiments were on embryos from krill acclimated to laboratory conditions. The hatching success of embryo batches varied enormously, from 0 to 98% (mean 27%). Both field and laboratory experiments showed that hatching success decreased markedly above 3.0°C. Our field experiments also showed an approximate doubling of the percentage of malformed nauplii at elevated temperatures, reaching 50% at 5.0°C. At 3.0°C or below, however, temperature was not the main factor driving the large variation in embryo hatching success. Our observations of highly variable and often low success of hatching to healthy nauplii suggest that indices of reproductive potential of female krill relate poorly to the subsequent production of viable krill larvae and may help to explain spatial discrepancies between the distribution of the spawning stock and larval distribution.

Ocean biology helps regulate global climate by fixing atmospheric CO2 and exporting it to deep waters as sinking detrital particles. New observations demonstrate that particle fragmentation is the principal factor controlling the depth to which these particles penetrate the ocean's interior, and hence how long the constituent carbon is sequestered from the atmosphere. The underlying cause is, however, poorly understood. We speculate that small, particle-associated copepods, which intercept and inadvertently break up sinking particles as they search for attached protistan prey, are the principle agents of fragmentation in the ocean. We explore this idea using a new marine ecosystem model. Results indicate that explicitly representing particle fragmentation by copepods in biogeochemical models offers a step change in our ability to understand the future evolution of biologically-mediated ocean carbon storage. Our findings highlight the need for improved understanding of the distribution, abundance, ecology and physiology of particle-associated copepods.

A carbon budget for the northwest European continental shelf seas (NWES) was synthesized using available estimates for coastal, pelagic and benthic carbon stocks and flows. Key uncertainties were identified and the effect of future impacts on the carbon budget were assessed. The water of the shelf seas contains between 210 and 230 Tmol of carbon and absorbs between 1.3 and 3.3 Tmol from the atmosphere annually. Off-shelf transport and burial in the sediments account for 60–100 and 0–40% of carbon outputs from the NWES, respectively. Both of these fluxes remain poorly constrained by observations and resolving their magnitudes and relative importance is a key research priority. Pelagic and benthic carbon stocks are dominated by inorganic carbon. Shelf sediments contain the largest stock of carbon, with between 520 and 1600 Tmol stored in the top 0.1 m of the sea bed. Coastal habitats such as salt marshes and mud flats contain large amounts of carbon per unit area but their total carbon stocks are small compared to pelagic and benthic stocks due to their smaller spatial extent. The large pelagic stock of carbon will continue to increase due to the rising concentration of atmospheric CO2, with associated pH decrease. Pelagic carbon stocks and flows are also likely to be significantly affected by increasing acidity and temperature, and circulation changes but the net impact is uncertain. Benthic carbon stocks will be affected by increasing temperature and acidity, and decreasing oxygen concentrations, although the net impact of these interrelated changes on carbon stocks is uncertain and a major knowledge gap. The impact of bottom trawling on benthic carbon stocks is unique amongst the impacts we consider in that it is widespread and also directly manageable, although its net effect on the carbon budget is uncertain. Coastal habitats are vulnerable to sea level rise and are strongly impacted by management decisions. Local, national and regional actions have the potential to protect or enhance carbon storage, but ultimately global governance, via controls on emissions, has the greatest potential to influence the long-term fate of carbon stocks in the northwestern European continental shelf.

Copepods are amongst the most abundant animals on our planet. Who knew?! These small (typically 1–10 mm) crustaceans are found in all of the world’s oceans and play an important role in regulating Earth’s climate. Like wildebeest in the Serengeti graze on grasslands and are food for lions, herbivorous copepods represent a vital link in oceanic food chains between microscopic algae and higher predators, such as fish, birds, and whales. A group of copepods called Calanus are particularly important in the Northern Hemisphere. These tiny-but-mighty animals also share the wildebeest’s need to make a large annual migration—but in their case, they sink thousands of meters downwards to spend the winter in the deep, dark ocean. Understanding the lives of marine copepods, and how their populations will respond to climate change, is crucial for predicting the future health of the marine environment and how it helps our planet.

Background and objective Surgery on renal tumors with venous tumor thrombus presents a high complication rate and non-negligible perioperative mortality. Our objective was to analyze the postoperative complications, their relationship with the level of the tumor thrombus and its potential predisposing factors. Materials and methods A retrospective analysis was conducted in 101 patients with renal and venous tumor thrombus operated on between 1988 and 2017. Two patients were excluded because of intraoperative pulmonary thromboembolism and exitus (2%). The postsurgical complications were classified according to Clavien–Dindo classification system. To compare the qualitative variables, we employed the chi-squared test. We performed a multivariate analysis using binary logistic regression to identify the independent predictors. Results Some type of postsurgical complication occurred in 34 (34.3%) patients, 11 (11.1%) of which were severe (Clavien III–V). There were significant differences in the total complications (p = 0.003) and severe complications (Clavien ≥ III; p = 0.03) depending on the level of the tumor thrombus.

Resumen Contexto La medicina basada en la evidencia tiene como objetivo apoyarse en la mejor informacion cientifica disponible para aplicarla a la practica clinica. Entender e interpretar la evidencia cientifica implica conocer los niveles de evidencia disponibles, donde las revisiones sistematicas y/o metaanalisis de ensayos clinicos son la cuspide de la piramide del nivel de evidencia. Adquisicion de la evidencia El proceso de revision debe estar bien desarrollado y planificado de antemano para reducir sesgos y eliminar estudios irrelevantes o de baja calidad. Los pasos a seguir para la realizacion de una revision sistematica incluyen: (i) formular correctamente la pregunta clinica a responder (PICO), (ii) desarrollo de un protocolo (criterios de inclusion y exclusion), (iii) realizar una busqueda bibliografica detallada y amplia, (iv) cribar los resumenes de los trabajos identificados en la busqueda y posteriormente de los textos completos seleccionados (PRISMA). Sintesis de la evidencia Una vez seleccionados los estudios se debe: (v) extraer en un formulario disenado en el protocolo los datos necesarios para resumir los estudios incluidos, (vi) evaluar los sesgos de cada estudio pudiendo identificar la calidad de la evidencia disponible y, por ultimo, (vii) desarrollar las tablas y el texto que sinteticen la evidencia. Conclusiones Una revision sistematica implica un resumen critico y reproducible de los resultados de las publicaciones disponibles sobre un mismo tema o pregunta clinica concreta. Con el fin de mejorar la escritura cientifica, se expone de una forma estructurada la metodologia para la realizacion de una revision sistematica.

Context The objective of evidence-based medicine is to employ the best scientific information available to apply to clinical practice. Understanding and interpreting the scientific evidence involves understanding the available levels of evidence, where systematic reviews and meta-analyses of clinical trials are at the top of the levels-of-evidence pyramid. Acquisition of evidence The review process should be well developed and planned to reduce biases and eliminate irrelevant and low-quality studies. The steps for implementing a systematic review include (i) correctly formulating the clinical question to answer (PICO), (ii) developing a protocol (inclusion and exclusion criteria), (iii) performing a detailed and broad literature search and (iv) screening the abstracts of the studies identified in the search and subsequently of the selected complete texts (PRISMA). Synthesis of the evidence Once the studies have been selected, we need to (v) extract the necessary data into a form designed in the protocol to summarise the included studies, (vi) assess the biases of each study, identifying the quality of the available evidence, and (vii) develop tables and text that synthesise the evidence. Conclusions A systematic review involves a critical and reproducible summary of the results of the available publications on a particular topic or clinical question. To improve scientific writing, the methodology is shown in a structured manner to implement a systematic review.

Resumen Introduccion y objetivo La cirugia de los tumores renales con trombosis venosa esta gravada con un porcentaje elevado de complicaciones y con una mortalidad perioperatoria no despreciable. Nuestro objetivo es analizar las complicaciones postoperatorias, su relacion con el nivel del trombo y sus posibles factores favorecedores. Materiales y metodos Analisis retrospectivo de 101 pacientes con tumores renales con trombosis venosa intervenidos entre 1988 y 2017. Se descartaron 2 pacientes por TEP intraoperatorio y exitus (2%). Las complicaciones posquirurgicas se clasificaron segun Clavien-Dindo. Para el contraste de variables cualitativas se ha utilizado el test de la Chi cuadrado. Se realizo un analisis multivariante mediante regresion logistica binaria para identificar las variables predictoras independientes. Resultados En 34 (34,3%) pacientes se produjo algun tipo de complicacion posquirurgica, siendo en 11 (11,1%) graves (Clavien III-IV). Existen diferencias significativas en las complicaciones totales (p = 0,003) y las graves (Clavien ≥ III) (p = 0,03) segun el nivel del trombo tumoral.

Deep-sea animals inhabiting the hadal zone (>6000 m deep) are frequently reported to occupy large bathymetric ranges, but details of intra-specific population structure and the underlying drivers remain poorly understood. Here we describe the population structure of the dominant SW Pacific hadal amphipod, Bathycallisoma schellenbergi, across its bathymetric range in the Kermadec (10,047 m) and New Hebrides (7156 m) trenches and explore the factors likely responsible for the observed patterns. These two trenches are relatively close geographically but underlie different water masses and are topographically isolated by the Kermadec fore-arc. The minimum depth of B. schellenbergi was ~1000 m shallower in the New Hebrides Trench than in the Kermadec Trench although similar patterns of ontogenetic stratification were present; juveniles were restricted to depths Hirondellea dubia, at mid-trench depths corresponded to maximum densities of B. schellenbergi , a trend that was reversed towards the trench axes regardless of actual depth. This suggests that the population structure and amphipod assemblages are more affected by how trench topography influences the distribution of food and potential ecological interactions, rather than simply by the effects of hydrostatic pressure.

The genus AsydatesCasey, 1895 is redefined and revised. ScelopristisMayor, 2004, new synonymy, is treated as a new junior subjective synonym. Asydates grandiceps (LeConte, 1866), new combination, Asydates irwini (Howell, 1979), new combination, and Asydates vandykei (Blaisdell, 1924), new combination, are treated as new combinations from Scelopristis, and Asydates ruficauda (Blaisdell, 1924), new combination, is transferred from Trichochrous Motschulsky. Pristoscelis schlingeriHowell, 1997, new synonymy, and Pristoscelis volkiHowell, 1979, new synonymy, are treated as junior subjective synonyms of A. ruficauda. Asydates chumash Mayor and Gimmel, new species, Asydates kumeyaay Mayor and Gimmel, new species, Asydates inexpectatus Mayor and Gimmel, new species, Asydates phantasma Mayor and Gimmel, new species, Asydates shoshone Mayor and Gimmel, new species, Asydates tongva Mayor and Gimmel, new species, and Asydates washoe Mayor and Gimmel, new species, are described. The genus PseudasydatesBlaisdell, 1938, status restored, is redefined as distinct from Asydates. Pseudasydates inyoensisBlaisdell, 1938, combination restored, is removed from Asydates and returned to Pseudasydates. Pseudasydates explanatus (Casey, 1895), new combination, is moved from Asydates, with Asydates puncticeps Blaisdell, 1924 treated as a junior subjective synonym. Members of Asydates occur primarily in California and the Great Basin Region of North America. Adult beetles are visitors to inflorescences of plants primarily of the genera Stephanomeria Nutt., Ericameria Nutt. (both Asteraceae) and Eriogonum Michx. (Polygonaceae), and adults show a pronounced seasonality skew towards mid-summer to fall. Adult males are characteristic for their enlarged heads and mandibles; we provide a hypothesis for the behavioral function of these structures.

There are very few Spanish studies that compare oncological outcomes following radical prostatectomy (RP) based on surgical approach, and their methodology is not appropriate.To compare oncological outcomes in terms of surgical margins (SM) and biochemical recurrence (BR) between open radical prostatectomy (ORP) and laparoscopic radical prostatectomy (LRP).Comparison of two cohorts (307 with ORP and 194 with LRP) between 2007-2015. Surgical margin status was defined as positive or negative, and BR as a PSA rise of0.4 ng/ml after surgery. To compare the qualitative variables, we employed the Chi-squared test, and ANOVA was used for quantitative variables. We performed a multivariate analysis using logistic regression to evaluate the predictive factors of SM, and a multivariate analysis using Cox regression to evaluate the predictive factors of BR.Gleason 7 (3+4) was determined in the surgical specimens of 43.5% of patients, and 31.7% had positive SM. The most frequent pathological stage was pT2c, on the 61.9% of the cases. No significant differences were found between both groups, except for extracapsular extension (p=0.001), more frequent in LRP. The median follow-up was 49 months. BR was seen in the 23% of patients, without significant differences between groups. In the multivariable analysis, only the D'Amico risk group behaved as an independent predictive factor of positive SM, and Gleason score and positive SM acted as independent predictive factors of BR.The surgical approach did not influence SM status or BR.

The transport of dissolved organic matter (DOM) across the land-ocean-aquatic-continuum (LOAC), from freshwater to the ocean, is an important yet poorly understood component of the global carbon budget. Exploring and quantifying this flux is a significant challenge given the complexities of DOM cycling across these contrasting environments. We developed a new model, UniDOM, that unifies concepts, state variables and parameterisations of DOM turnover across the LOAC. Terrigenous DOM is divided into two pools, T1 (strongly-UV-absorbing) and T2 (non- or weakly-UV-absorbing), that exhibit contrasting responses to microbial consumption, photooxidation and flocculation. Data are presented to show that these pools are amenable to routine measurement based on specific UV absorbance (SUVA). In addition, an autochtonous DOM pool is defined to account for aquatic DOM production. A novel aspect of UniDOM is that rates of photooxidation and microbial turnover are parameterised as an inverse function of DOM age. Model results, which indicate that ~ 5% of the DOM originating in streams may penetrate into the open ocean, are sensitive to this parameterisation, as well as rates assigned to turnover of freshly-produced DOM. The predicted contribution of flocculation to DOM turnover is remarkably low, although a mechanistic representation of this process in UniDOM was considered unachievable because of the complexities involved. Our work highlights the need for ongoing research into the mechanistic understanding and rates of photooxidation, microbial consumption and flocculation of DOM across the different environments of the LOAC, along with the development of models based on unified concepts and parameterisations.

Recurrence trends after renal cell cancer nephrectomy are not clearly defined.To evaluate recurrence trends according to recurrence risk groups (RRG).Retrospective analysis of 696 patients with renal cell cancer treated with nephrectomy between 1990-2010. Three RRG were defined according to the presence of anatomopathological variables (pTpN stage, nuclear grade, tumor necrosis [TN], sarcomatoid differentiation [SD], positive resection margin [RM]): -Low RG (LRG): pT1pNx-0 G1-4, pT2pNx-0 G1-2; no TN, SD and/or RM (+). -Intermediate RG (IRG): pT2pNx-0 G3-4; pT3-4pNx-0 G1-2; LRG with TN. -High RG (HRG): pT3-4pNx-0 G3-4; pT1-4pN+; IRG with TN and/or SD; LRG with SD and/or RM (+). The Kaplan-Meier method has been used to evaluate recurrence-free survival as a function of RRG. The log-rank test was used to evaluate differences between survival curves.The median follow-up was 105 (IQR 63-148) months. Of the total series, 177 (25.4%) patients presented recurrence: distant 15.9%, local 4.9% and 4.6% distant and local. The recurrence rate varied according to the RRG with values of 72.9% for HRG, 16.9% for IRG and 10.2% for LRG (p=.0001). Most cases in LRG presented single organ recurrence (72.2%) (p=.006). The LRG experienced recurrence as single metastasis in 50% of cases, compared to 30% and 18.6% in IRG and HRG, respectively (p=.009). The most common sites of recurrence were lung and abdomen. Lung recurrence predominated in the HRG (72.9%) (p=.0001) and abdominal, in the LRG (83.3%) with a tendency to significance (p=.15).Recurrence rates (especially bone and lung) increase with higher RG. Single organ recurrences and single metastases are more frequent in LRG.

This special issue presents some of the key findings from the pelagic component of the UK Shelf Sea Biogeochemistry Research Programme, carried out on the northwest European shelf between March 2014 and August 2015. The project aimed to address two issues: (1) how does a temperate shelf sea sustain an annual net drawdown and export of atmospheric CO2 without running out of inorganic nutrients, and (2) what uncertainties in processes or parameterisations within current ecosystem models can be reduced by a coordinated, multi-disciplinary observational programme covering the full seasonal cycle? Working with partners across Europe, the net annual drawdown of atmospheric CO2 over the entire northwest European shelf was confirmed. This demonstrated the context and impetus for a 17-month process study in the Celtic Sea, using a long-term mooring array and several research cruises, addressing shelf sea physics, inorganic and organic nutrient and carbon cycling, and bacterial, phytoplankton and zooplankton roles and dynamics. It was clear from the physics that all the carbon absorbed through the sea surface over one year was not exported to the open ocean. Physical transports were too weak and too slow to transport all the carbon-laden water over a wide shelf sea to the shelf edge within one year. The shelf sea must therefore be able to store carbon in a form that prevents release back to the atmosphere for a timescale that is sufficient to allow more episodic (timescales >1 year) exchange events to both remove the excess carbon and top-up the shelf pool of inorganic nutrients. The results presented in this special issue illustrate the likely key role of recalcitrant dissolved organic carbon in storing carbon on the shelf and highlight the need for longer-term measurements or monitoring to understand the nature and timing of potentially large but infrequent exchange events between the shelf and open ocean.

Antarctic krill, Euphausia superba, have a circumpolar distribution but are concentrated within the south-west Atlantic sector, where they support a unique food web and a commercial fishery. Within this sector, our first goal was to produce quantitative distribution maps of all six ontogenetic life stages of krill (eggs, nauplii plus metanauplii, calyptopes, furcilia, juveniles, and adults), based on a compilation of all available post 1970s data. Using these maps, we then examined firstly whether “hotspots” of egg production and early stage nurseryoccurred, and secondly whether the available habitat was partitioned between the successive life stages during the austral summer and autumn, when krill densities can be high. To address these questions, we compiled larval krill density records and extracted data spanning 41 years (1976–2016) from the existing KRILLBASE-abundance and KRILLBASE-length-frequency databases. Although adult males and females of spawning age were widely distributed, the distribution of eggs, nauplii and metanauplii indicates that spawning is most intense over the shelf and shelf slope. This contrasts with the distributionsof calyptope and furcilia larvae, which were concentrated further offshore, mainly in the Southern Scotia Sea. Juveniles, however, were strongly concentrated over shelves along the Scotia Arc. Simple environmental analyses based on water depth and mean water temperature suggest that krill associate with different habitats over the course of their life cycle. From the early to late part of the austral season, juvenile distribution moves from ocean to shelf, opposite in direction to that for adults. Such habitat partitioning may reduce intraspecific competition for food, which has been suggested to occur when densities are exceptionally high during years of strong recruitment. It also prevents any potential cannibalism by adults on younger stages. Understanding the location of krill spawning and juvenile development in relation to potentially overlapping fishing activities is needed to protect the health of the south-west Atlantic sector ecosystem.

Hadal ocean sediments, found at sites deeper than 6,000m water depth, are thought to contain microbial communities distinct from those at shallower depths due to high hydrostatic pressures and higher abundances of organic matter. These communities may also differ from one other as a result of geographical isolation. Here we compare microbial community composition in surficial sediments of two hadal environments-the Mariana and Kermadec trenches-to evaluate microbial biogeography at hadal depths. Sediment microbial consortia were distinct between trenches, with higher relative sequence abundances of taxa previously correlated with organic matter degradation present in the Kermadec Trench. In contrast, the Mariana Trench, and deeper sediments in both trenches, were enriched in taxa predicted to break down recalcitrant material and contained other uncharacterized lineages. At the 97% similarity level, sequence-abundant taxa were not trench-specific and were related to those found in other hadal and abyssal habitats, indicating potential connectivity between geographically isolated sediments. Despite the diversity of microorganisms identified using culture-independent techniques, most isolates obtained under in situ pressures were related to previously identified piezophiles. Members related to these same taxa also became dominant community members when native sediments were incubated under static, long-term, unamended high-pressure conditions. Our results support the hypothesis that there is connectivity between sediment microbial populations inhabiting the Mariana and Kermadec trenches while showing that both whole communities and specific microbial lineages vary between trench of collection and sediment horizon depth. This in situ biodiversity is largely missed when incubating samples within pressure vessels and highlights the need for revised protocols for high-pressure incubations.

There are few biological datasets that span large bathymetric ranges with sufficient resolution to identify trends across the abyssal and hadal transition zone, particularly over multiple trenches. Here, scavenging Amphipoda were collected from three trenches in the South Pacific Ocean at bathyal to hadal depths. Diversity and community structure were examined from stations within the Kermadec Trench (1490–9908 m) and New Hebrides Trench (2000–6948 m) and additional data were included from the South Fiji Basin (4000 m) and Peru-Chile Trench (4602–8074 m). The hadal community structure of the Kermadec and New Hebrides trenches were distinct from the surrounding abyssal and bathyal depths and correlated to hydrostatic pressure and POC flux. Low POC flux in the New Hebrides Trench and South Fiji Basin best explained the dissimilarity in abyssal community structure from those of the disparate Kermadec and Peru-Chile trenches. POC flux also best explained patterns in hadal community structure with the Kermadec and New Hebrides Trench communities showing greater similarity to each other than to the eutrophic Peru-Chile Trench. Hydrostatic pressure was the strongest driver of intra-trench assemblage composition in all trench environments. A unimodal pattern of species diversity, peaking between 4000 and 5000 m, was best explained by hydrostatic pressure and temperature.

Blooms of harmful algae are increasing globally, yet their impacts on copepods, an important link between primary producers and higher trophic levels, remain largely unknown. Algal toxins may have direct, negative effects on the survival of copepods. They may also indirectly affect copepod survival by deterring feeding and thus decreasing the availability of energy and nutritional resources. Here we present a series of short-term (24 h) experiments in which the cosmopolitan marine copepod, Acartia tonsa, was exposed to a range of concentrations of the toxic dinoflagellate, Alexandrium catenella (strain 1119/27, formerly Alexandrium tamarense), with and without the presence of alternative, non-toxic prey (Rhodomonas sp.). We also present the toxin profile concentrations for A. catenella. The survival and feeding of A. tonsa was not affected across the range of concentrations recorded for A. catenella in the field; increased mortality of A. tonsa was only discernible when A. catenella was present at concentrations that exceed their reported environmental concentrations by two orders of magnitude. The observed lethal median concentration (LC 50) for A. tonsa exposed to A. catenella was 12.45 ng STX eq L − 1. We demonstrate that A. tonsa is capable of simultaneously ingesting both toxic and non-toxic algae, but increases clearance rates towards non-toxic prey as the proportional abundance of toxic A. catenella increases. The ability to actively select non-toxic algae whilst also ingesting toxic algae suggests that consumption of the latter does not cause physical incapacitation and thus does not affect ingestion in A. tonsa. This work shows that short-term exposure to toxic A. catenella is unlikely to elicit major effects on the grazing or survival of A. tonsa. However, more work is needed to understand the longer-term and sub-lethal effects of toxic algae on marine copepods.

The flow of terrestrial carbon to rivers and inland waters is a major term in the global carbon cycle. The organic fraction of this flux may be buried, remineralized or ultimately stored in the deep ocean. The latter can only occur if terrestrial organic carbon can pass through the coastal and estuarine filter, a process of unknown efficiency. Here, data are presented on the spatial distribution of terrestrial fluorescent and chromophoric dissolved organic matter (FDOM and CDOM, respectively) throughout the North Sea, which receives organic matter from multiple distinct sources. We use FDOM and CDOM as proxies for terrestrial dissolved organic matter (tDOM) to test the hypothesis that tDOM is quantitatively transferred through the North Sea to the open North Atlantic Ocean. Excitation emission matrix fluorescence and parallel factor analysis (EEM-PARAFAC) revealed a single terrestrial humic-like class of compounds whose distribution was restricted to the coastal margins and, via an inverse salinity relationship, to major riverine inputs. Two distinct sources of fluorescent humic-like material were observed associated with the combined outflows of the Rhine, Weser and Elbe rivers in the south-eastern North Sea and the Baltic Sea outflow to the eastern central North Sea. The flux of tDOM from the North Sea to the Atlantic Ocean appears insignificant, although tDOM export may occur through Norwegian coastal waters unsampled in our study. Our analysis suggests that the bulk of tDOM exported from the Northwest European and Scandinavian landmasses is buried or remineralized internally, with potential losses to the atmosphere. This interpretation implies that the residence time in estuarine and coastal systems exerts an important control over the fate of tDOM and needs to be considered when evaluating the role of terrestrial carbon losses in the global carbon cycle.

In this work, we map the absorption properties of the French crust by analyzing the decay properties of coda waves. Estimation of the coda quality factor $$Q_{c}$$ in five non-overlapping frequency-bands between 1 and 32 Hz is performed for more than 12,000 high-quality seismograms from about 1700 weak to moderate crustal earthquakes recorded between 1995 and 2013. Based on sensitivity analysis, $$Q_{c}$$ is subsequently approximated as an integral of the intrinsic shear wave quality factor $$Q_{i}$$ along the ray connecting the source to the station. After discretization of the medium on a 2-D Cartesian grid, this yields a linear inverse problem for the spatial distribution of $$Q_{i}$$ . The solution is approximated by redistributing $$Q_{c}$$ in the pixels connecting the source to the station and averaging over all paths. This simple procedure allows to obtain frequency-dependent maps of apparent absorption that show lateral variations of $$50\%$$ at length scales ranging from 50 km to 150 km, in all the frequency bands analyzed. At low frequency, the small-scale geological features of the crust are clearly delineated: the Meso-Cenozoic basins (Aquitaine, Brabant, Southeast) appear as strong absorption regions, while crystalline massifs (Armorican, Central Massif, Alps) appear as low absorption zones. At high frequency, the correlation between the surface geological features and the absorption map disappears, except for the deepest Meso-Cenozoic basins which exhibit a strong absorption signature. Based on the tomographic results, we explore the implications of lateral variations of absorption for the analysis of both instrumental and historical seismicity. The main conclusions are as follows: (1) current local magnitude $$M_{L}$$ can be over(resp. under)-estimated when absorption is weaker(resp. stronger) than the nominal value assumed in the amplitude-distance relation; (2) both the forward prediction of the earthquake macroseismic intensity field and the estimation of historical earthquake seismological parameters using macroseismic intensity data are significantly improved by taking into account a realistic 2-D distribution of absorption. In the future, both $$M_{L}$$ estimations and macroseismic intensity attenuation models should benefit from high-resolution models of frequency-dependent absorption such as the one produced in this study.

Evaluation of the effectiveness of cognitive biopsy (CB) in patients with clinical suspicion of prostate cancer (PC), and at least one negative biopsy (TRB).Retrospective study of 144 patients with at least one previous TRB and magnetic resonance imaging (MRI). The MRI nodules were classified based on PI-RADS v2 grouping pZa, pZpl and pZpm as the peripheral zone(PZ), Tza, Tzp and CZ as the transitional zone (TZ), and the AS zones as the anterior zone (AZ). A biopsy was indicated for nodules ≥PI-RADS 3. Uni and multivariate analysis was undertaken (logistic regression) to identify variables relating to a PI-RADS 3 tumour on biopsy.The median age was 67 (IQR: 62-72) years, the median PSA was 8.2 (IQR: 6.2-12) ng/ml. A nodule was identified on MRI in the PZ in 97 (67.4%) cases, in the TZ in 29 (20.1%), and in the AZ in 41 (28.5%). PC was diagnosed on biopsy in 64 (44%) patients. The cancer rate in the PI-RADS 3 lesions was 17.5% (7/40), in the PI-RADS 4 47.3% (35/73), and in the PI-RADS 5 lesions it was 73.3% (22/29) (p=.0001). Multivariable analysis with variables that could influence the biopsy result in patients with PI-RADS 3: None (age, PSA, number of previous biopsies, rectal examination, PSAD, prostate volume or number of extracted cylinders) behaved as an independent tumour predictor.The diagnostic performance of CB in patients with at least one previous negative biopsy was 44%, increasing according to the PI-RADS grade, and low in PI-RADS 3. No clinical variable predictive of cancer was found in patients with PI-RADS 3.

The aim of this study is to compare performance of two biopsy approaches in patients with at least one previous negative prostate biopsy (PB): classical transrectal biopsy (ClTB) versus cognitive registration biopsy (COG-TB).A retrospective study of 205 patients with at least one negative PB. 144 (70.2%) patients underwent a prior mpMRI and 61 (29.8%) patients did not. Nodule classification was carried out according PI-RADS version 2. Peripheral zone (PZ) grouped pZa, pZpl and pZpm areas, transition zone (TZ) Tza, Tzp and Cz areas, and anterior zone (AZ) AS areas. COG-TB was conducted in patients with previous mpMRI (144); while in the remaining 61 (29.8%) patients a ClTB of PZ and TZ was performed. Statistical analysis was performed using Chi square and T-student tests for qualitative and quantitative variables, respectively. Multivariate analysis was carried out in order to identify predictive variables of prostate cancer.Median patient age was 68 (IQR 62-72) years, median PSA was 8.3 (IQR 6.2-11.7) ng/ml and median previous biopsies was 1 (IQR 1-2). Digital rectal examinations (DRE) findings were normal in 169 (82.4%) patients and suspicious in 36 (17.6%) patients (cT2a-b in 34 patients and cT2c in 2). Median prostate volume was 48 (IQR 38-65) cc. Statistically significant differences in PSAD between both groups were found (P=.03). Transrectal ultrasound (TRUS) showed hypoechoic nodules in 8 (13.1%) ClTB patients and in 62 (43.1%) COG-TB patients (P=.0001). The median number of biopsy cylinders per set of prostate biopsies was 10 (IQR 10-10) in ClTB group and 11 (IQR 9-13) in COG-TB group (P=.75). Cancer was diagnosed in 74 (36.1%) patients: of them, 10 (16.4%) were ClTB patients and 64 (44.4%) COG-TB (P=.0001). Tumors classification was as follow: ISUP-1: 34 (45.9%), ISUP-2: 21 (28.4%), ISUP-3: 9 (12.2%), ISUP-4: 7 (9.5%) and ISUP-5: 3 (4.1%). No significant statistical differences were found (P=.89). The median number of biopsy cylinders impaired per set of prostate biopsies was 1 (IQR 1-5) in ClTB group and 2 (IQR 1-4) in COG-TB group (P=.93). Regarding independent predictive variables for prostate cancer the results were: age (OR=12.05; P=.049), suspicious DRE (OR=2.64; P=.04), hypoechoic nodule (OR=2.20; P=.03) and mpMRI +COG-TB sequence (OR=3.49; P=.003).In patients with at least one negative PB, mpMRI +COG-TB sequence improves 3.5 (OR=3.49) times the diagnosis prostate vs. ClTB.

Zooplankton on continental shelves represent an important intermediary in the transfer of energy and matter from phytoplankton to the wider ecosystem. Their taxonomic composition and trophic interactions with phytoplankton vary in space and time, and interpreting the implications of this constantly evolving landscape remains a major challenge. Here we combine plankton taxonomic data with the analysis of biovolume spectra and stable isotopes to provide insights into the trophic interactions that occur in a shelf sea ecosystem (Celtic Sea) across the spring-summer-autumn transition. Biovolume spectra captured the seasonal development of the zooplankton community well, both in terms of total biomass and trophic positioning, and matched trophic positions estimated by stable isotope analysis. In early April, large microplankton (63–200 µm) occupied higher trophic positions than mesozooplankton (>200 µm), likely reflecting the predominance of nanoplankton (2–20 µm) that were not readily available to mesozooplankton grazers. Biomass and number of trophic levels increased during the spring bloom as elevated primary production allowed for a higher abundance of predatory species. During July, the plankton assemblage occupied relatively high trophic positions, indicating important links to the microbial loop and the recycling of organic matter. The strong correlation between biomass and community trophic level across the study suggests that the Celtic Sea is a relatively enclosed and predominantly energy-limited ecosystem. The progression of the zooplankton biomass and community structure within the central shelf region was different to that at the shelf-break, potentially reflecting increased predatory control of copepods by macrozooplankton and pelagic fishes at the shelf break. We suggest that the combination of size spectra and stable isotope techniques are highly complementary and useful for interpreting the seasonal progression of trophic interactions in the plankton.

One of the inherent features of kidney tumours is the capacity to spread inside the venous system as tumour thrombi. The aim of this study was to assess in patients with stage pT3apN0cM0 kidney cancer whether venous tumour involvement influenced tumour recurrence.A retrospective analysis of patients with stage pT3apN0cM0 kidney cancer treated with radical nephrectomy between 1990-2015. Univariate and multivariate Cox regression analysis to identify predictive variables and independent predictive variables relating to recurrence.The results of 153 patients were studied. The median follow-up was 82 (IQR 36-117) months. Recurrence-free survival at 5 years was 58.9% with a median of 97 (95% CI 49.9-144.1) months. Seventy-seven (50.3%) patients recurred. Seventy cases 70 (90.9%) had distant metastases, 17 (14.2%) of these patients had local recurrence in the bed of nephrectomy. Tumour necrosis (p=.0001), and microvascular invasion (p=.001) were identified as independent predictors of tumour recurrence in the multivariable analysis.In our series, after multivariable analysis, venous tumour extension was not related to recurrence. Tumour necrosis and microvascular infiltration did behave as independent predictive factors of tumour recurrence.

The objective of evidence-based medicine is to employ the best scientific information available to apply to clinical practice. Understanding and interpreting the scientific evidence involves understanding the available levels of evidence, where systematic reviews and meta-analyses of clinical trials are at the top of the levels-of-evidence pyramid.The review process should be well developed and planned to reduce biases and eliminate irrelevant and low-quality studies. The steps for implementing a systematic review include (i) correctly formulating the clinical question to answer (PICO), (ii) developing a protocol (inclusion and exclusion criteria), (iii) performing a detailed and broad literature search and (iv) screening the abstracts of the studies identified in the search and subsequently of the selected complete texts (PRISMA).Once the studies have been selected, we need to (v) extract the necessary data into a form designed in the protocol to summarise the included studies, (vi) assess the biases of each study, identifying the quality of the available evidence, and (vii) develop tables and text that synthesise the evidence.A systematic review involves a critical and reproducible summary of the results of the available publications on a particular topic or clinical question. To improve scientific writing, the methodology is shown in a structured manner to implement a systematic review.

Mudflats are highly productive regions that are important to local, regional and global aspects of ecology and biogeochemistry. They sequester organic carbon, recycle nutrient elements such as nitrogen and phosphorus, release climate-active gases to the atmosphere, and provide sustenance to countless resident and migrant animals. Microorganisms that remain hidden from sight underpin all of these, and many other, crucial ecosystem functions and services. This chapter explores the roles of microorganisms in mudflat sediments, their interactions with the other residents, and some of the contemporary techniques used to study and quantify the ways in which they influence biogeochemical cycles.

WOS:000441489600006; International audience; There has been an upsurge of interest in trait-based approaches to zooplankton, modelling the seasonal changes in the feeding modes of zooplankton in relation to phytoplankton traits such as size or motility. We examined this link at two English Channel plankton monitoring sites south of Plymouth (L4 and El). At L4 there was a general transition from diatoms in spring to motile microplankton in summer and autumn, but this was not mirrored in the succession of copepod feeding traits; for example the ambushing Oithona similis dominated during the spring diatom bloom. At nearby El we measured seasonality of food and grazers, finding strong variation between 2014 and 2015 but overall low mesozooplankton biomass (median 4.5 mg C m(-3)). We also made a seasonal grazing study of five copepods with contrasting feeding modes (Calculus helgolandicus, Centropages typicus, Acartia clausi, Pseudocalanus elongatus and Oithona similis), counting the larger prey items from the natural seston. All species of copepod fed on all food types and differences between their diets were only subtle; the overriding driver of diet was the composition of the prey field. Even the smaller copepods fed on copepod nauplii at significant rates, supporting previous suggestions of the importance of intra-guild predation. All copepods, including O. similis, were capable of tackling extremely long ( \textgreater 500 mu m) diatom chains at clearance rates comparable to those on ciliates. Maximum observed prey:predator length ratios ranged from 0.12 (C. helgolandicus) up to 0.52 (O. similis). Unselective feeding behaviour and the ability to remove highly elongated cells have implications for how copepod feeding is represented in ecological and biogeochemical models.

The Piton de la Fournaise volcano exhibits frequent eruptions preceded by seismic swarms and is a good target to test hypotheses about magmatically induced variations in seismic wave properties. We use a permanent station network and a portable broadband network to compare seismic anisotropy measured via shear wave splitting with geodetic displacements, ratios of compressional to shear velocity (Vp/Vs), earthquake focal mechanisms, and ambient noise correlation analysis of surface wave velocities and to examine velocity and stress changes from 2000 through 2012. Fast directions align radially to the central cone and parallel to surface cracks and fissures, suggesting stress-controlled cracks. High Vp/Vs ratios under the summit compared with low ratios under the flank suggest spatial variations in the proportion of fluid-filled versus gas-filled cracks. Secular variations of fast directions (ϕ) and delay times (dt) between split shear waves are interpreted to sense changing crack densities and pressure. Delay times tend to increase while surface wave velocity decreases before eruptions. Rotations of ϕ may be caused by changes in either stress direction or fluid pressure. These changes usually correlate with GPS baseline changes. Changes in shear wave splitting measurements made on multiplets yield several populations with characteristic delay times, measured incoming polarizations, and fast directions, which change their proportion as a function of time. An eruption sequence on 14 October 2010 yielded over 2000 shear wave splitting measurements in a 14 h period, allowing high time resolution measurements to characterize the sequence. Stress directions from a propagating dike model qualitatively fit the temporal change in splitting.

Elevated temperature causes metabolism and respiration to increase in poikilothermic organisms. We hypothesized that invertebrate consumers will therefore require increasingly carbon-rich diets in a warming environment because the increased energetic demands are primarily met using compounds rich in carbon, that is, carbohydrates and lipids. Here, we test this hypothesis using a new stoichiometric model that has carbon (C) and nitrogen (N) as currencies. Model predictions did not support the hypothesis, indicating instead that the nutritional requirements of invertebrates, at least in terms of food quality expressed as C∶N ratio, may change little, if at all, at elevated temperature. Two factors contribute to this conclusion. First, invertebrates facing limitation by nutrient elements such as N have, by default, excess C in their food that can be used to meet the increased demand for energy in a warming environment, without recourse to extra dietary C. Second, increased feeding at elevated temperature compensates for the extra demands of metabolism to the extent that, when metabolism and intake scale equally with temperature (have the same Q10), the relative requirement for dietary C and N remains unaltered. Our analysis demonstrates that future climate-driven increases in the C∶N ratios of autotroph biomass will likely exacerbate the stoichiometric mismatch between nutrient-limited invertebrate grazers and their food, with important consequences for C sequestration and nutrient cycling in ecosystems.

The expansion of global aquaculture activities is important for the wellbeing of future generations in terms of employment and food security. Rearing animals in open-exchange cages permits the release of organic wastes, some of which ultimately reaches the underlying sediments. The development of rapid, quantitative and objective monitoring techniques is therefore central to the environmentally sustainable growth of the aquaculture industry. Here, we demonstrate that fish farm-derived organic wastes can be readily detected at the seafloor by quantifying sediment phospholipid fatty acids (PLFAs) and their carbon stable isotope signatures. Observations across five farms reveal that farm size and/or distance away from it influence the spatial distribution of the generated organic wastes and their effect on benthic bacterial biomass. Comparison to the isotopic signatures of fish feed-derived PLFAs indicates that 16:0 and 18:1(n-9) are potential biomarkers for fish farm-derived organic wastes. Our results suggest that stable isotope analysis of sediment PLFAs has potential for monitoring the environmental performance of aquaculture activities, particularly given the increasing prevalence of terrigenous organic matter in aquaculture feed stocks because it is isotopically district to marine organic matter.

Consistent with a warming climate, birds are shifting the timing of their migrations, but it remains unclear to what extent these shifts have kept pace with the changing environment. Because bird migration is primarily cued by annually consistent physiological responses to photoperiod, but conditions at their breeding grounds depend on annually variable climate, bird arrival and climate-driven spring events would diverge. We combined satellite and citizen science data to estimate rates of change in phenological interval between spring green-up and migratory arrival for 48 breeding passerine species across North America. Both arrival and green-up changed over time, usually in the same direction (earlier or later). Although birds adjusted their arrival dates, 9 of 48 species did not keep pace with rapidly changing green-up and across all species the interval between arrival and green-up increased by over half a day per year. As green-up became earlier in the east, arrival of eastern breeding species increasingly lagged behind green-up, whereas in the west—where green-up typically became later—birds arrived increasingly earlier relative to green-up. Our results highlight that phenologies of species and trophic levels can shift at different rates, potentially leading to phenological mismatches with negative fitness consequences.

Aims To examine if and how species and phylogenetic diversity change in relation to disturbance, we conducted a review of ecological lit-erature by testing the consistency of the relationship between phylo-genetic diversity and disturbance and compared taxonomic groups, type of disturbance and ecosystem/habitat context. We provide a case study of the phylogenetic diversity–disturbance relationship in angiosperm plant communities of a boreal forest region, compared with types of natural and anthropogenic disturbances and plant growth forms. Methods Using a large-scale sampling plot network along a complete (0–100%) anthropogenic disturbance gradient in the boreal biome, we compared the changes of angiosperm plant commu-nity structure and composition across plots. We estimated natu-ral disturbance with historical records of major fires. We then calculated phylogenetic diversity indexes and determined spe-cies richness in order to compare linear and polynomial trends along disturbance gradients. We also compared the changes of community structure for different types of anthropogenic distur-bances and examined how the relationships between species and phylogenetic diversity and disturbance regimes vary among three different life forms (i.e. forbs, graminoids and woody plants).

The two North American species currently placed in Dolichosoma Stephens, namely D. foveicolle (Kirby, 1837) (widespread in North America) and D. tenuiforme Horn, 1880 (“Texas”), were critically examined. After investigation of type specimens and comparison with Palearctic members of Dolichosoma and Psilothrix Kuster, D. foveicolle is transferred to the latter genus as Psilothrix foveicollis (Kirby, 1837), new combination, and D. tenuiforme is considered to be based on a mislabeled specimen of D. lineare (Rossi, 1794) and becomes a new junior synonym of that species. Consequently, the genus Dolichosoma is not represented in the North American fauna, and Psilothrix is recognized as the only truly Holarctic genus of Dasytinae.

Coryphaenoides armatus is a cosmopolitan deep-sea fish that plays a major role in the ecology of abyssal ecosystems. We investigated the trophic ecology and physiology of this species by determining the δ13C, δ15N and fatty acid signatures of muscle, liver and ovary tissues of individuals collected from ∼2700 m to the north and south of the Charlie-Gibbs Fracture Zone (CGFZ) of the Mid-Atlantic Ridge, NE Atlantic. Fatty acid and δ13C data both suggested that C. armatus shows an ontogenetic dietary shift, with the relative contributions of benthic and pelagic prey decreasing and increasing respectively as the animals grow. They also indicated that dietary overlap between animals living to the north and south of the CGFZ increases as they grow, suggesting that larger animals forage over greater distances and are not hindered by the presence of the CGFZ. Comparison of tissue-specific fatty acid signatures with previously published data suggests compositional homeostasis of the fatty acids 20:5(n−3) and 22:6(n−3) in the muscle, and 18:1(n−9) in the liver tissues. We ascribe this primarily to strict physiological requirements for these compounds, rather than simply to their abundance in the diet. We pose several speculative mechanisms to explain the observed trends in tissue-specific δ13C and δ15N values, illustrating some of the numerous processes that can influence the isotopic signatures of bulk tissues.

Resumen Contexto Se pretende evaluar el conocimiento actual acerca del tratamiento del carcinoma de celulas renales (CCR) que afecta al injerto en los pacientes trasplantados de rinon. Adquisicion de evidencia Revision de la literatura actual basada en el analisis de los casos publicados de cirugia conservadora de nefronas en el carcinoma de celulas renales que afecta al injerto renal. Sintesis de evidencia Se han descrito 51 casos de nefrectomia parcial en injerto renal, con una supervivencia del injerto del 88% y un indice de recurrencia del 6%. La mayoria de los pacientes estaban asintomaticos al diagnostico (75%) y el tamano medio de las lesiones fue de 2,8 cm. La tecnica mas utilizada fue la enucleacion. El 77% de las pautas inmunosupresoras incluian ciclosporina A. Seis pacientes fueron tratados mediante radiofrecuencia y 2 recibieron crioablacion percutanea, con una supervivencia del 100% de los injertos y un unico caso de recidiva, que requirio segundo tratamiento. Conclusiones La cirugia conservadora del parenquima renal es una opcion terapeutica empleada ante CCR sobre injerto renal que consigue buen control oncologico y buena supervivencia del injerto. La modificacion de la inmunosupresion con la supresion de ciclosporina A y la introduccion de inhibidores de mTOR podria ser una medida adecuada en estos pacientes y merece futuras investigaciones.