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A commentary on: Feeling the Conflict: The Crucial Role of Conflict Experience in Adaptationby Desender, K., Van Opstal, F., and Van den Bussche, E. (2014). Psychol. Sci. 25, 675–683. doi:10.1177/0956797613511468
Conflict adaptation in masked priming has recently been proposed to rely not on successful conflictresolution but rather on conflict experience (Desender et al., 2014). We re-assessed this proposal ina direct replication and also tested a potential confound due toconflict strength. The data supported this alternative view, but also failed to replicate basic conflict adaptation effects of the original studydespite considerable power.
Accurate and detailed spatial soil information is essential for environmental modelling, risk assessment and decision making. The use of Remote Sensing data as secondary sources of information in digital soil mapping has been found to be cost effective and less time consuming compared to traditional soil mapping approaches. But the potentials of Remote Sensing data in improving knowledge of local scale soil information in West Africa have not been fully explored. This study investigated the use of high spatial resolution satellite data (RapidEye and Landsat), terrain/climatic data and laboratory analysed soil samples to map the spatial distribution of six soil properties–sand, silt, clay, cation exchange capacity (CEC), soil organic carbon (SOC) and nitrogen–in a 580 km2 agricultural watershed in south-western Burkina Faso. Four statistical prediction models–multiple linear regression (MLR), random forest regression (RFR), support vector machine (SVM), stochastic gradient boosting (SGB)–were tested and compared. Internal validation was conducted by cross validation while the predictions were validated against an independent set of soil samples considering the modelling area and an extrapolation area. Model performance statistics revealed that the machine learning techniques performed marginally better than the MLR, with the RFR providing in most cases the highest accuracy. The inability of MLR to handle non-linear relationships between dependent and independent variables was found to be a limitation in accurately predicting soil properties at unsampled locations. Satellite data acquired during ploughing or early crop development stages (e.g. May, June) were found to be the most important spectral predictors while elevation, temperature and precipitation came up as prominent terrain/climatic variables in predicting soil properties. The results further showed that shortwave infrared and near infrared channels of Landsat8 as well as soil specific indices of redness, coloration and saturation were prominent predictors in digital soil mapping. Considering the increased availability of freely available Remote Sensing data (e.g. Landsat, SRTM, Sentinels), soil information at local and regional scales in data poor regions such as West Africa can be improved with relatively little financial and human resources.
Predators of highly defensive prey likely develop cost-reducing adaptations. The ant Megaponera analis is a specialized termite predator, solely raiding termites of the subfamily Macrotermitinae (in this study, mostly colonies of Pseudocanthotermes sp.) at their foraging sites. The evolutionary arms race between termites and ants led to various defensive mechanisms in termites (for example, a caste specialized in fighting predators). Because M. analis incurs high injury/mortality risks when preying on termites, some risk-mitigating adaptations seem likely to have evolved. We show that a unique rescue behavior in M. analis, consisting of injured nestmates being carried back to the nest, reduces combat mortality. After a fight, injured ants are carried back by their nestmates; these ants have usually lost an extremity or have termites clinging to them and are able to recover within the nest. Injured ants that are forced experimentally to return without help, die in 32% of the cases. Behavioral experiments show that two compounds, dimethyl disulfide and dimethyl trisulfide, present in the mandibular gland reservoirs, trigger the rescue behavior. A model accounting for this rescue behavior identifies the drivers favoring its evolution and estimates that rescuing enables maintenance of a 28.7% larger colony size. Our results are the first to explore experimentally the adaptive value of this form of rescue behavior focused on injured nestmates in social insects and help us to identify evolutionary drivers responsible for this type of behavior to evolve in animals.
Background: Allergic rhinitis and asthma as single entities affect more boys than girls in childhood but more females in adulthood. However, it is unclear if this prevalence sex-shift also occurs in allergic rhinitis and concurrent asthma. Thus, our aim was to compare sex-specifc differences in the prevalence of coexisting allergic rhinitis and asthma in childhood, adolescence and adulthood.
Methods: Post-hoc analysis of systematic review with meta-analysis concerning sex-specific prevalence of allergic rhinitis. Using random-effects meta-analysis, we assessed male–female ratios for coexisting allergic rhinitis and asthma in children (0–10 years), adolescents (11–17) and adults (> 17). Electronic searches were performed using MEDLINE and EMBASE for the time period 2000–2014. We included population-based observational studies, reporting coexisting allergic rhinitis and asthma as outcome stratifed by sex. We excluded non-original or non-population-based studies, studies with only male or female participants or selective patient collectives.
Results: From a total of 6539 citations, 10 studies with a total of 93,483 participants met the inclusion criteria. The male–female ratios (95% CI) for coexisting allergic rhinitis and asthma were 1.65 (1.52; 1.78) in children (N = 6 studies), 0.61 (0.51; 0.72) in adolescents (N = 2) and 1.03 (0.79; 1.35) in adults (N = 2). Male–female ratios for allergic rhinitis only were 1.25 (1.19; 1.32, N = 5) in children, 0.80 (0.71; 0.89, N = 2) in adolescents and 0.98 (0.74; 1.30, N = 2) in adults, respectively.
Conclusions: The prevalence of coexisting allergic rhinitis and asthma shows a clear male predominance in childhood and seems to switch to a female predominance in adolescents. This switch was less pronounced for allergic rhinitis only.
Background: Fruits and vegetables are rich in compounds with proposed antioxidant, anti-allergic and anti-inflammatory properties, which could contribute to reduce the prevalence of asthma and allergic diseases.
Objective: We investigated the association between asthma, and chronic rhino-sinusitis (CRS) with intake of fruits and vegetables in European adults.
Methods: A stratified random sample was drawn from the Global Allergy and Asthma Network of Excellence (GA\(^2\)LEN) screening survey, in which 55,000 adults aged 15–75 answered a questionnaire on respiratory symptoms. Asthma score (derived from self-reported asthma symptoms) and CRS were the outcomes of interest. Dietary intake of 22 subgroups of fruits and vegetables was ascertained using the internationally validated GA\(^2\)LEN Food Frequency Questionnaire. Adjusted associations were examined with negative binomial and multiple regressions. Simes procedure was used to control for multiple testing.
Results: A total of 3206 individuals had valid data on asthma and dietary exposures of interest. 22.8% reported having at least 1 asthma symptom (asthma score ≥1), whilst 19.5% had CRS. After adjustment for potential confounders, asthma score was negatively associated with intake of dried fruits (β-coefficient −2.34; 95% confidence interval [CI] −4.09, −0.59), whilst CRS was statistically negatively associated with total intake of fruits (OR 0.73; 95% CI 0.55, 0.97). Conversely, a positive association was observed between asthma score and alliums vegetables (adjusted β-coefficient 0.23; 95% CI 0.06, 0.40). None of these associations remained statistically significant after controlling for multiple testing.
Conclusion and clinical relevance: There was no consistent evidence for an association of asthma or CRS with fruit and vegetable intake in this representative sample of European adults.
A central question to biology is how pathogenic bacteria initiate acute or chronic infections. Here we describe a genetic program for cell-fate decision in the opportunistic human pathogen Staphylococcus aureus, which generates the phenotypic bifurcation of the cells into two genetically identical but different cell types during the course of an infection. Whereas one cell type promotes the formation of biofilms that contribute to chronic infections, the second type is planktonic and produces the toxins that contribute to acute bacteremia. We identified a bimodal switch in the agr quorum sensing system that antagonistically regulates the differentiation of these two physiologically distinct cell types. We found that extracellular signals affect the behavior of the agr bimodal switch and modify the size of the specialized subpopulations in specific colonization niches. For instance, magnesium-enriched colonization niches causes magnesium binding to S. aureusteichoic acids and increases bacterial cell wall rigidity. This signal triggers a genetic program that ultimately downregulates the agr bimodal switch. Colonization niches with different magnesium concentrations influence the bimodal system activity, which defines a distinct ratio between these subpopulations; this in turn leads to distinct infection outcomes in vitro and in an in vivo murine infection model. Cell differentiation generates physiological heterogeneity in clonal bacterial infections and helps to determine the distinct infection types.
An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization of the PIDE problem with a multigrid scheme that includes a fast multilevel integration of the Fredholm operator allowing the fast solution of the PIDE problem. Theoretical estimates of second-order accuracy and results of local Fourier analysis of convergence of the proposed multigrid scheme are presented. Results of numerical experiments validate these estimates and demonstrate optimal computational complexity of the proposed framework.
Background
The aim of this 4D flow cardiovascular magnetic resonance (CMR) follow-up study was to investigate longitudinal changes in aortic hemodynamics in adolescent patients with Marfan syndrome (MFS).
Methods
4D flow CMR for the assessment of in-vivo 3D blood flow with full coverage of the thoracic aorta was performed twice (baseline scan t1/follow-up scan t2) in 19 adolescent MFS patients (age at t1: 12.7 ± 3.6 years, t2: 16.2 ± 4.3 years) with a mean follow-up duration of 3.5 ± 1.2 years. Ten healthy volunteers (24 ± 3.8 years) served as a control group. Data analysis included aortic blood flow visualization by color-coded 3D pathlines, and grading of flow patterns (helices/vortices) on a 3-point scale (none, moderate, severe; blinded reading, 2 observers). Regional aortic peak systolic velocities and systolic 3D wall shear stress (WSS) along the entire aortic wall were quantified. Z-Scores of the aortic root and proximal descending aorta (DAo) were assessed.
Results
Regional systolic WSS was stable over the follow-up duration, except for a significant decrease in the proximal inner DAo segment (p = 0.02) between t1 and t2. MFS patients revealed significant lower mean systolic WSS in the proximal inner DAo compared with volunteers (0.78 ± 0.15 N/m\(^{2}\)) at baseline t1 (0.60 ± 0.18 N/m\(^{2}\); p = 0.01) and follow-up t2 (0.55 ± 0.16 N/m\(^{2}\); p = 0.001). There were significant relationships (p < 0.01) between the segmental WSS in the proximal inner DAo, DAo Z-scores (r = −0.64) and helix/vortex pattern grading (r = −0.55) at both t1 and t2. The interobserver agreement for secondary flow patterns assessment was excellent (Cohen’s k = 0.71).
Conclusions
MFS patients have lower segmental WSS in the inner proximal DAo segment which correlates with increased localized aberrant vortex/helix flow patterns and an enlarged diameter at one of the most critical sites for aortic dissection. General aortic hemodynamics are stable but these subtle localized DAo changes are already present at young age and tend to be more pronounced in the course of time.
Since exposure therapy for anxiety disorders incorporates extinction of contextual anxiety, relapses may be due to reinstatement processes. Animal research demonstrated more stable extinction memory and less anxiety relapse due to vagus nerve stimulation (VNS). We report a valid human three-day context conditioning, extinction and return of anxiety protocol, which we used to examine effects of transcutaneous VNS (tVNS). Seventy-five healthy participants received electric stimuli (unconditioned stimuli, US) during acquisition (Day1) when guided through one virtual office (anxiety context, CTX+) but never in another (safety context, CTX−). During extinction (Day2), participants received tVNS, sham, or no stimulation and revisited both contexts without US delivery. On Day3, participants received three USs for reinstatement followed by a test phase. Successful acquisition, i.e. startle potentiation, lower valence, higher arousal, anxiety and contingency ratings in CTX+ versus CTX−, the disappearance of these effects during extinction, and successful reinstatement indicate validity of this paradigm. Interestingly, we found generalized reinstatement in startle responses and differential reinstatement in valence ratings. Altogether, our protocol serves as valid conditioning paradigm. Reinstatement effects indicate different anxiety networks underlying physiological versus verbal responses. However, tVNS did neither affect extinction nor reinstatement, which asks for validation and improvement of the stimulation protocol.