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Parasites inflict many costs on their hosts. Understanding host–parasite relationship eco-evolutionary dynamics needs appreciation of how parasites affect individual fitness, survival and reproductive potential, and how they combine to influence population demography, dynamics and viability; also, how these processes drive microevolutionary processes that define natural and sexual selection. We synthesise work on the relationship between the red grouse and its main parasite, a gastrointestinal nematode. At individual level, we show how parasites impose a physiological cost, measured by immunosuppression and increased oxidative stress, and how their impact varies depending on contexts. We describe how parasite infection constrains expression of sexually selected traits and summarise how relationships between parasite, host and environment shape host population demography and dynamics. Genetic analyses in red grouse suggest nematode burden is moderately heritable, underpinned by a potentially large array of genes involved in the immune system, energy balance and broader homeostatic processes. There is no clear association between allele frequencies among populations and differences in nematode burdens. Possibly, beneficial alleles for parasite resistance cannot spread through the population due to the strong diversifying e?ects of gene ?ow and genetic drift.
Psychiatry's most recent foray into the area of risk and prevention has been spear-headed by work on at-risk mental states for psychotic disorders. Twenty-five years' research and clinical application have led us to reformulate the clinical evolution of these syndromes, blurred unhelpful conceptual boundaries between childhood and adult life by adopting a developmental view and has changed the shape of many mental health services as part of a global movement to increase quality. But there are problems: fragmentary psychotic experiences are common in young people but transition from risk-state to full syndrome is uncommon away from specialist clinics with rarefied referrals and can, anyway, be subtle; diagnostic over-shadowing by the prospect of schizophrenia and other psychotic disorders may divert clinical attention from the kaleidoscopic and disabling range of probably treatable psychopathology with which people with risk syndromes present. We use a 19th Century lyric poem, The Lady of Shallot, as an allegory for Psychiatry warning us against regarding these mental states only as pointers towards diagnoses that probably will not occur. Viewed from the fresh perspective of common mental disorders they tell us a great deal about the psychopathological crucible of the second and third decades, the nature of diagnosis, and point towards new treatment paradigms.
To what extent meditation techniques (which incorporate practices to regulate attention, construct individual values, or deconstruct self-related assumptions), are more or less effective than relaxation therapy in the treatment of anxiety, is not clear. The aim of this study was to examine the effectiveness of meditation compared to relaxation in reducing anxiety. A systematic review from PubMed, Embase, PsycInfo and the Cochrane Central was conducted. A meta-analysis of 14 RCTs (n = 862 participants suffering from anxiety disorders or high trait anxiety) was performed. Effect sizes (ESs) were determined by Hedges’ g. Heterogeneity, risk of publication bias, quality of studies/interventions, and researcher allegiance, were evaluated. Meditation techniques incorporated attentional elements, and five of them also added constructive practices. No studies were found using deconstructive exercises. The overall ES was g = −0.23 [95% confidence interval (CI) −0.40 to −0.07], favouring meditation (number needed to treat = 7.74). Heterogeneity was low (I2 = 2; 95% CI 0 to 56). There was no evidence of publication bias, but few studies and interventions were of high quality, and allegiance might be moderating results. Meditation seems to be a bit more effective than relaxation in the treatment of anxiety, and it might also remain more effective at 12-month follow-up. However, more research using the full spectrum of meditation practices to treat different anxiety disorders, including independent studies to avoid researcher allegiance, is needed if we are to have a precise idea of the potential of these techniques compared to relaxation therapy.
Preliminary evidence suggests that hoarding disorder (HD) and obsessive-compulsive disorder (OCD) may show distinct patterns of brain activation during executive performance, although results have been inconclusive regarding the specific neural correlates of their differential executive dysfunction. In the current study, we aim to evaluate differences in brain activation between patients with HD, OCD and healthy controls (HCs) during response inhibition, response switching and error processing.
We assessed 17 patients with HD, 18 patients with OCD and 19 HCs. Executive processing was assessed inside a magnetic resonance scanner by means of two variants of a cognitive control protocol (i.e. stop- and switch-signal tasks), which allowed for the assessment of the aforementioned executive domains.
OCD patients performed similar to the HCs, differing only in the number of successful go trials in the switch-signal task. However, they showed an anomalous hyperactivation of the right rostral anterior cingulate cortex during error processing in the switch-signal task. Conversely, HD patients performed worse than OCD and HC participants in both tasks, showing an impulsive-like pattern of response (i.e. shorter reaction time and more commission errors). They also exhibited hyperactivation of the right lateral orbitofrontal cortex during successful response switching and abnormal deactivation of frontal regions during error processing in both tasks.
Our results support that patients with HD and OCD present dissimilar cognitive profiles, supported by distinct neural mechanisms. Specifically, while alterations in HD resemble an impulsive pattern of response, patients with OCD present increased error processing during response conflict protocols.
In this work, the degradation of methyl orange (MO) was analyzed by direct light with visible radiation (λ > 450 nm) of a dye solution in the presence of silicon nanowires (SiNWs) or silicon nanowires with copper nanoparticles (SiNWs-CuNPs). The SiNWs were synthesized by metal assisted etching from monocrystalline silicon wafers in aqueous HF / AgNO3 solution, and the CuNPs were deposited on the SiNWs via electroless. Discoloration with visible irradiation of aqueous methyl orange solution (C14H14N3NaOS) in the presence of SiNWs showed an efficiency of 71% after 120 min of illumination. The deposition of copper nanoparticles on the nanowires improves the efficiency of the photocatalytic reaction achieving 89% discoloration after 120 min exposure to visible light. The MO photocatalytic degradation with visible radiation in aqueous solution shows to be efficient in discoloration reaching up to 92% in a time of 150 min in the presence of SiNWs-CuNPs.
The work shows the preparation and characterization of composite materials using a polymer as a matrix (ABS) and carbon black or a graphenic material (graphene or graphene foam). The materials were individually mixed with the polymer and the process parameters were established in an extruder with capacity for temperature control starting at laboratory conditions and up to 600 °C. The process parameters were adjusted to form filaments that were subsequently used in a 3D printer. The parameters of the printing process were adjusted to achieve the production of flat prototypes. These prototypes were characterized by Digital Optical Microscopy. The degree of homogeneity of the prototypes and the working ranges for the graphene material concentrations were determined. Even though the characterizations were done in flat samples, 3D printing allows obtaining a great diversity of structure that broadens the diversity of applications for such kind of composite materials.
The potential of a mass asteroid impact on Earth to disturb the chemosynthetic communities at global scale is discussed. Special emphasis is made on the potential influence on anammox communities and their implications in the nitrogen biogeochemical cycle. According to our preliminary estimates, anammox communities could be seriously affected as a consequence of global cooling and the large process of acidification usually associated with the occurrence of this kind of event. The scale of affectations could vary in a scenario like the Chicxulub as a function of the amount of soot, depth of the water column and the deposition rate for sulphates assumed in each case. The most severe affectations take place where the amount of soot and sulphates produced during the event is higher and the scale of time of settlements for sulphates is short, of the order of 10 h. In this extreme case, the activity of anammox is considerably reduced, a condition that may persist for several years after the impact. Furthermore, the impact of high levels of other chemical compounds like sulphates and nitrates associated with the occurrence of this kind of event are also discussed.
The effectiveness of Early Intervention in Psychosis (EIP) services for individuals with a first episode of psychosis (FEP) could be thwarted by high rates of early disengagement.
To investigate which factors predict disengagement with EIP services.
Using data from a naturalistic cohort of 786 EIP clients in East Anglia (UK), we investigated the association between sociodemographic and clinical predictors and disengagement using univariable and multivariable Cox proportional hazards models.
Over half (54.3%) of our sample were discharged before receiving 3 years of EIP care, with 92 (11.7%) participants discharged due to disengagement. Milder negative symptoms, more severe hallucinations, not receiving an FEP diagnosis, polysubstance use and being employed were associated with greater disengagement.
Our findings highlight heterogeneous reasons for disengagement with EIP services. For some patients, early disengagement may hinder efforts to sustain positive long-term EIP outcomes. Efforts to identify true FEP cases and target patients with substance use problems and more severe positive symptoms may increase engagement.
Following the introduction of new standards for early intervention in psychosis (EIP) in England, EIP services are accepting referrals for people aged 35–65. The Cambridgeshire and Peterborough EIP service (CAMEO) aimed to explore the immediate implications for the service, especially with regards to referral numbers and sources. Data were collected from April 2016 to June 2017.
Referrals for over-35s represented 25.7% of all new referrals. Fifty per cent of referrals for over-35s were accepted onto caseload (40.2% for under-35s). The over-35s were more likely to be referred from acute and secondary mental health services (P < 0.01) and had longer durations of untreated psychosis than the under-35s (P = 0.02).
CAMEO has received a significantly higher number of referrals as a result of age inclusivity, with an increased proportion of patients suffering from severe, acute psychotic presentations and existing mental health difficulties. This has implications for service planning.
To compare the epidemiology, clinical characteristics, and mortality of patients with bloodstream infections (BSI) caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) versus ESBL-producing Klebsiella pneumoniae (ESBL-KP) and to examine the differences in clinical characteristics and outcome between BSIs caused by isolates with CTX-M versus other ESBL genotypes
As part of the INCREMENT project, 33 tertiary hospitals in 12 countries retrospectively collected data on adult patients diagnosed with ESBL-EC BSI or ESBL-KP BSI between 2004 and 2013. Risk factors for ESBL-EC versus ESBL-KP BSI and for 30-day mortality were examined by bivariate analysis followed by multivariable logistic regression.
The study included 909 patients: 687 with ESBL-EC BSI and 222 with ESBL-KP BSI. ESBL genotype by polymerase chain reaction amplification of 286 isolates was available. ESBL-KP BSI was associated with intensive care unit admission, cardiovascular and neurological comorbidities, length of stay to bacteremia >14 days from admission, and a nonurinary source. Overall, 30-day mortality was significantly higher in patients with ESBL-KP BSI than ESBL-EC BSI (33.7% vs 17.4%; odds ratio, 1.64; P=.016). CTX-M was the most prevalent ESBL subtype identified (218 of 286 polymerase chain reaction-tested isolates, 76%). No differences in clinical characteristics or in mortality between CTX-M and non–CTX-M ESBLs were detected.
Clinical characteristics and risk of mortality differ significantly between ESBL-EC and ESBL-KP BSI. Therefore, all ESBL-producing Enterobacteriaceae should not be considered a homogeneous group. No differences in outcomes between genotypes were detected.
In the frame of the COST ACTION ‘EMBOS’ (Development and implementation of a pan-European Marine Biodiversity Observatory System), coverage of intertidal macroalgae was estimated at a range of marine stations along the European coastline (Subarctic, Baltic, Atlantic, Mediterranean). Based on these data, we tested whether patterns in macroalgal diversity and distribution along European intertidal rocky shores could be explained by a set of meteo-oceanographic variables. The variables considered were salinity, sea surface temperature, photosynthetically active radiation, significant wave height and tidal range and were compiled from three different sources: remote sensing, reanalysis technique and in situ measurement. These variables were parameterized to represent average conditions (mean values), variability (standard deviation) and extreme events (minimum and maximum values). The results obtained in this study contribute to reinforce the EMBOS network approach and highlight the necessity of considering meteo-oceanographic variables in long-term assessments. The broad spatial distribution of pilot sites has allowed identification of latitudinal and longitudinal gradients manifested through species composition, diversity and dominance structure of intertidal macroalgae. These patterns follow a latitudinal gradient mainly explained by sea surface temperature, but also by photosynthetically active radiation, salinity and tidal range. Additionally, a longitudinal gradient was also detected and could be linked to wave height.
As is well known, the corrosion of embedded steel reinforced depends strongly of the concrete resistivity, which is related directly with the water contained into its porous network. Environment plays an important role on resistivity, due to have a direct correspondence with the relative humidity and temperature. In these terms, ingress or output of water is favored or hampered by the environmental parameters, as well as its fluctuations. This work presents a proposal of instrumented system to generate a map of electrical resistivity at concrete samples by using superficial and embedded electrodes. Mathematical analysis of equivalent circuit revealed the importance of the impedance of electrodes utilized, to simplify measures. Concrete samples were exposed to different relative humidity focused to try to obtain the relation between relative humidity and resistivity. An array of two electrodes distributed in a matrix was manufactured to apply a signal of direct current at first electrode and measure the resultant current at second electrode. The system applies a programmed sequence of switch to turn on and turn off to realize measurements over established zone and, in this form, allows identify zones with potentials gradients. Also, do easy the monitoring of concrete resistivity evolution in function of time and humidity conditions.
Examining how variability in population abundance and distribution is allotted among different spatial scales can inform of processes that are likely to generate that variability. Results of studies dealing with scale issues in marine benthic communities suggest that variability is concentrated at small spatial scales (from tens of centimetres to few metres) and that spatial patterns of variation are consistent across ecosystems characterized by contrasting physical and biotic conditions, but this has not been formally tested. Here we quantified the variability in the distribution of intertidal rocky shore communities at a range of spatial scales, from tens of centimetres to thousands of kilometres, both in the NE Atlantic and the Mediterranean, and tested whether the observed patterns differed between the two basins. We focused on canopy-forming macroalgae and associated understorey assemblages in the low intertidal, and on the distribution of Patella limpets at mid intertidal levels. Our results highlight that patterns of spatial variation, at each scale investigated, were consistent between the Atlantic and the Mediterranean, suggesting that similar ecological processes operate in these regions. In contrast with former studies, variability in canopy cover, species richness and limpet abundance was equally distributed among spatial scales, possibly reflecting the fingerprint of multiple processes. Variability in community structure of low intertidal assemblages, instead, peaked at the largest scale, suggesting that oceanographic processes and climatic gradients may be important. We conclude that formal comparisons of variability across scales nested in contrasting systems are needed, before any generalization on patterns and processes can be made.
Coastal ecosystems are highly complex and driven by multiple environmental factors. To date we lack scientific evidence for the relative contribution of natural and anthropogenic drivers for the majority of marine habitats in order to adequately assess the role of different stressors across the European seas. Such relationship can be investigated by analysing the correlation between environmental variables and biotic patterns in multivariate space and taking into account non-linearities. Within the framework of the EMBOS (European Marine Biodiversity Observatory System) programme, hard bottom intertidal communities were sampled in a standardized way across European seas. Links between key natural and anthropogenic drivers and hard bottom communities were analysed using Boosted Regression Trees modelling. The study identified strong interregional variability and showed that patterns of hard bottom macroalgal and invertebrate communities were primarily a function of tidal regime, nutrient loading and water temperature (anomalies). The strength and shape of functional form relationships varied widely however among types of organisms (understorey algae composing mostly filamentous species, canopy-forming algae or sessile invertebrates) and aggregated community variables (cover or richness). Tidal regime significantly modulated the effect of nutrient load on the cover and richness of understorey algae and sessile invertebrates. In contrast, hydroclimate was more important for canopy algae and temperature anomalies and hydroclimate separately or interactively contributed to the observed patterns. The analyses also suggested that climate-induced shifts in weather patterns may result in the loss of algal richness and thereby in the loss of functional diversity in European hard bottom intertidal areas.
The Endangered Cuvier's gazelle Gazella cuvieri is an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2 in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.
Within the COST action EMBOS (European Marine Biodiversity Observatory System) the degree and variation of the diversity and densities of soft-bottom communities from the lower intertidal or the shallow subtidal was measured at 28 marine sites along the European coastline (Baltic, Atlantic, Mediterranean) using jointly agreed and harmonized protocols, tools and indicators. The hypothesis tested was that the diversity for all taxonomic groups would decrease with increasing latitude. The EMBOS system delivered accurate and comparable data on the diversity and densities of the soft sediment macrozoobenthic community over a large-scale gradient along the European coastline. In contrast to general biogeographic theory, species diversity showed no linear relationship with latitude, yet a bell-shaped relation was found. The diversity and densities of benthos were mostly positively correlated with environmental factors such as temperature, salinity, mud and organic matter content in sediment, or wave height, and related with location characteristics such as system type (lagoons, estuaries, open coast) or stratum (intertidal, subtidal). For some relationships, a maximum (e.g. temperature from 15–20°C; mud content of sediment around 40%) or bimodal curve (e.g. salinity) was found. In lagoons the densities were twice higher than in other locations, and at open coasts the diversity was much lower than in other locations. We conclude that latitudinal trends and regional differences in diversity and densities are strongly influenced by, i.e. merely the result of, particular sets and ranges of environmental factors and location characteristics specific to certain areas, such as the Baltic, with typical salinity clines (favouring insects) and the Mediterranean, with higher temperatures (favouring crustaceans). Therefore, eventual trends with latitude are primarily indirect and so can be overcome by local variation of environmental factors.
The objective of the present study was to assess the reproducibility of data-driven dietary patterns in different samples extracted from similar populations. Dietary patterns were extracted by applying principal component analyses to the dietary information collected from a sample of 3550 women recruited from seven screening centres belonging to the Spanish breast cancer (BC) screening network (Determinants of Mammographic Density in Spain (DDM-Spain) study). The resulting patterns were compared with three dietary patterns obtained from a previous Spanish case–control study on female BC (Epidemiological study of the Spanish group for breast cancer research (GEICAM: grupo Español de investigación en cáncer de mama)) using the dietary intake data of 973 healthy participants. The level of agreement between patterns was determined using both the congruence coefficient (CC) between the pattern loadings (considering patterns with a CC≥0·85 as fairly similar) and the linear correlation between patterns scores (considering as fairly similar those patterns with a statistically significant correlation). The conclusions reached with both methods were compared. This is the first study exploring the reproducibility of data-driven patterns from two studies and the first using the CC to determine pattern similarity. We were able to reproduce the EpiGEICAM Western pattern in the DDM-Spain sample (CC=0·90). However, the reproducibility of the Prudent (CC=0·76) and Mediterranean (CC=0·77) patterns was not as good. The linear correlation between pattern scores was statistically significant in all cases, highlighting its arbitrariness for determining pattern similarity. We conclude that the reproducibility of widely prevalent dietary patterns is better than the reproducibility of more population-specific patterns. More methodological studies are needed to establish an objective measurement and threshold to determine pattern similarity.