Drd4 gene polymorphisms are associated with personality variation in a passerine bird

Polymorphisms in several neurotransmitter-associated genes have been associated with variation in human personality traits. Among the more promising of such associations is that between the human dopamine receptor D4 gene (Drd4) variants and novelty-seeking behaviour. However, genetic epistasis, genotype–environment interactions and confounding environmental factors all act to obscure genotype–personality relationships. Such problems can be addressed by measuring personality under standardized conditions and by selection experiments, with both approaches only feasible with non-human animals. Looking for similar Drd4 genotype–personality associations in a free-living bird, the great tit (Parus major), we detected 73 polymorphisms (66 SNPs, 7 indels) in the P. major Drd4 orthologue. Two of the P. major Drd4 gene polymorphisms were investigated for evidence of association with novelty-seeking behaviour: a coding region synonymous single nucleotide polymorphism (SNP830) and a 15 bp indel (ID15) located 5′ to the putative transcription initiation site. Frequencies of the three Drd4 SNP830 genotypes, but not the ID15 genotypes, differed significantly between two P. major lines selected over four generations for divergent levels of ‘early exploratory behaviour’ (EEB). Strong corroborating evidence for the significance of this finding comes from the analysis of free-living, unselected birds where we found a significant association between SNP830 genotypes and differing mean EEB levels. These findings suggest that an association between Drd4 gene polymorphisms and animal personality variation predates the divergence of the avian and mammalian lineages. Furthermore, this work heralds the possibility of following microevolutionary changes in frequencies of behaviourally relevant Drd4 polymorphisms within populations where natural selection acts differentially on different personality types

Small molecule behavior and the 3Bg state of biacetyl

Below excitation energies of 22 500 cm−1 biacetyl behaves as a small molecule as evidenced by the pressure dependence of its phosphorescence and the structure of the excitation spectrum. The sudden transition to large (statistical) molecule behavior at this energy can be explained by the presence of a 3Bg state for which there is also theoretical evidence

Ontwikkeling van schelpdierbestanden op de droogvallende platen van de Waddenzee

Hoe staat het met de schelpdieren in de Waddenzee? Aan de hand van langjarige tijdreeksen geven we een overzicht van de ontwikkeling van Mossel (Mytilus edulis), Kokkel (Cerastoderma edule), Nonnetje (Macoma balthica) en nieuwkomer de Japanse oester (Crassostrea gigas). Hierbij speelt de vraag welke factoren bepalend zijn voor de aantalsontwikkeling van de verschillende soorten

Cerebral effects of glucagon‐like peptide‐1 receptor blockade before and after Roux‐en‐Y gastric bypass surgery in obese women: A proof‐of‐concept resting‐state functional MRI study

Aim: To assess the effects of Roux‐en‐Y gastric bypass surgery (RYGB)‐related changes in glucagon‐like peptide‐1 (GLP‐1) on cerebral resting‐state functioning in obese women. Materials and Methods: In nine obese females aged 40‐54 years in the fasted state, we studied the effects of RYGB and GLP‐1 on five a priori selected networks implicated in food‐ and reward‐related processes as well as environment monitoring (default mode, right frontoparietal, basal ganglia, insula/anterior cingulate and anterior cingulate/orbitofrontal networks). Results: Before surgery, GLP‐1 receptor blockade (using exendin9‐39) was associated with increased right caudate nucleus (basal ganglia network) and decreased right middle frontal (right frontoparietal network) connectivity compared with placebo. RYGB resulted in decreased right orbitofrontal (insula/anterior cingulate network) connectivity. In the default mode network, after surgery, GLP‐1 receptor blockade had a larger effect on connectivity in this region than GLP‐1 receptor blockade before RYGB (all PFWE < .05). Results remained similar after correction for changes in body weight. Default mode and right frontoparietal network connectivity changes were related to changes in body mass index and food scores after RYGB. Conclusions: These findings suggest GLP‐1 involvement in resting‐state networks related to food and reward processes and monitoring of the internal and external environment, pointing to a potential role for GLP‐1–induced changes in resting‐state connectivity in RYGB‐mediated weight loss and appetite control

Metabolic rate throughout the annual cycle reveals the demands of an Arctic existence in Great Cormorants

Aquatic endotherms living in polar regions are faced with a multitude of challenges, including low air and water temperatures and low illumination, especially in winter. Like other endotherms from cold environments, Great Cormorants (Phalacrocorax carbo) living in Arctic waters were hypothesized to respond to these challenges through combination of high daily rate of energy expenditure (DEE) and high food requirements, which are met by a high rate of catch per unit effort (CPUE). CPUE has previously been shown in Great Cormorants to be the highest of any diving bird. In the present study, we tested this hypothesis by making the first measurements of DEE and foraging activity of Arctic-dwelling Great Cormorants throughout the annual cycle. We demonstrate that, in fact, Great Cormorants have surprisingly low rates of DEE. This low DEE is attributed primarily to very low levels of foraging activity, particularly during winter, when the cormorants spent only 2% of their day submerged. Such a low level of foraging activity can only be sustained through consistently high foraging performance. We demonstrate that Great Cormorants have one of the highest recorded CPUEs for a diving predator; 18.6 g per minute submerged (95% prediction interval 13.0-24.2 g/min) during winter. Temporal variation in CPUE was investigated, and highest CPUE was associated with long days and shallow diving depths. The effect of day length is attributed to seasonal variation in prey abundance. Shallow diving leads to high CPUE because less time is spent swimming between the surface and the benthic zone where foraging occurs. Our study demonstrates the importance of obtaining accurate measurements of physiology and behavior from free-living animals when attempting to understand their ecology

Pain and autonomic dysfunction in patients with sarcoidosis and small fibre neuropathy

Small fibre neuropathy (SFN) has been demonstrated in sarcoidosis. However, a systematic analysis of neuropathic pain and autonomic symptoms, key features of SFN, has not been performed. Clinimetric evaluation of pain and autonomic symptoms using the neuropathic pain scale (NPS) and the modified Composite Autonomic Symptoms Scale (mCOMPASS) was used in sarcoidosis patients for this study. A total of 91 sarcoidosis patients (n = 23 without SFN symptoms, n = 43 with SFN symptoms but normal intraepidermal nerve fibre density (IENFD), n = 25 with SFN symptoms and reduced IENFD) were examined. NPS and mCOMPASS were assessed twice (reliability studies). Severity of pain was compared between the subgroups. Correlation between NPS and a visual analogue pain scale (VAS) was assessed (validity studies). Healthy controls (n = 105) completed the mCOMPASS for comparison with patients’ scores. Patients with sarcoidosis, SFN complaints, and reduced IENFD demonstrated more severe pain scores on the NPS. The mCOMPASS differentiated between subjects with and without SFN symptoms. A significant correlation was obtained between the NPS and VAS, indicating good construct validity. Good reliability values were obtained for all scales. The use of the NPS to evaluate SFN symptoms is suggested, as it shows differences between patients with SFN symptoms with normal or reduced IENFD values. The mCOMPASS might be used to select patients for further testing

A recipe for postfledging survival in great tits Parus major: be large and be early (but not too much)

Survival of juveniles during the postfledging period can be markedly low, which may have major consequences on avian population dynamics. Knowing which factors operating during the nesting phase affect postfledging survival is crucial to understand avian breeding strategies. We aimed to obtain a robust set of predictors of postfledging local survival using the great tit (Parus major) as a model species. We used mark–recapture models to analyze the effect of hatching date, temperatures experienced during the nestling period, fledging size and body mass on first-year postfledging survival probability of great tit juveniles. We used data from 5192 nestlings of first clutches ringed between 1993 and 2010. Mean first-year postfledging survival probability was 15.2%, and it was lower for smaller individuals, as well as for those born in either very early or late broods. Our results stress the importance of choosing an optimum hatching period, and raising large chicks to increase first-year local survival probability in the studied population.Secretaría de Estado de Investigación, Desarrollo e Innovación (Grant/Award Number: ‘CGL2013-48001-C2-1-P’)Peer reviewe