76 research outputs found
The genomic basis of cichlid fish adaptation within the deepwater âtwilight zoneâ of Lake Malawi
Deepwater environments are characterized by low levels of available light at narrow spectra, great hydrostatic pressure, and low levels of dissolved oxygenâconditions predicted to exert highly specific selection pressures. In Lake Malawi over 800 cichlid species have evolved, and this adaptive radiation extends into the âtwilight zoneâ below 50 m. We use population-level RAD-seq data to investigate whether four endemic deepwater species (Diplotaxodon spp.) have experienced divergent selection within this environment. We identify candidate genes including regulators of photoreceptor function, photopigments, lens morphology, and haemoglobin, many not previously implicated in cichlid adaptive radiations. Colocalization of functionally linked genes suggests coadapted âsupergeneâ complexes. Comparisons of Diplotaxodon to the broader Lake Malawi radiation using genome resequencing data revealed functional substitutions and signatures of positive selection in candidate genes. Our data provide unique insights into genomic adaptation within deepwater habitats, and suggest genome-level specialization for life at depth as an important process in cichlid radiation
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Patients with Severe Uncontrolled Asthma: Perception of Asthma Control and its Management
Introduction
The aim of our observational study was to understand how patients with uncontrolled severe asthma perceive asthma control, and to assess their views on the role of healthcare professionals (HCPs) and other stakeholders in asthma management.
Methods
In total, 200 patients with uncontrolled, severe asthma living in Canada, France, Germany, Italy, Spain, the UK, or the USA registered on the Carenity asthma community responded to a patient survey.
Results
While 62% of respondents indicated they knew a lot about asthma, they were not entirely satisfied with its control. The two most helpful tools considered important in long-term asthma control were centered on learning, with tips on asthma control (76%), as well as information on asthma and its causes (67%). Although asthma education programs were accessible to less than half (44%) of the respondents, 72% said they would find them useful. In the previous year, most patients (78%) consulted a specialist; however, while 54% of respondents participated in shared decision-making (SDM) concerning their treatment, less than one-third (29%) felt their opinion had been considered, and only 27% said it helped their HCPs to develop an informed action plan. However, 48% believed that SDM would help them feel more confident in achieving long-term control. Most respondents consulted emergency room doctors or nurse practitioners because of their uncontrolled severe asthma, finding them persuasive sources of information. Additionally, patient advocacy organizations (PAGs) were considered as a preferred (12%) or persuasive (6%) source by only a few patients.
Conclusion
Most people with uncontrolled severe asthma were well informed about their disease. However, better information on asthma management would be useful for patients, with HCPs involved in this process. SDM was welcomed by respondents, but, to be successful, the patientsâ opinions should be taken into consideration when forming an asthma management action plan
Lateral line system diversification during the early stages of ecological speciation in cichlid fish
Background: The mechanosensory lateral line system is an important sensory modality in fishes, informing multiple behaviours related to survival including finding food and navigating in dark environments. Given its ecological importance, we may expect lateral line morphology to be under disruptive selection early in the ecological speciation process. Here we quantify the lateral line system morphology of two ecomorphs of the cichlid fish Astatotilapia calliptera in crater Lake Masoko that have diverged from common ancestry within the past 1,000Â years. Results: Based on geometric morphometric analyses of CT scans, we show that the zooplanktivorous benthic ecomorph that dominates the deeper waters of the lake has large cranial lateral line canal pores, relative to those of the nearshore invertebrate-feeding littoral ecomorph found in the shallower waters. In contrast, fluorescence imaging revealed no evidence for divergence between ecomorphs in the number of either superficial or canal neuromasts. We illustrate the magnitude of the variation we observe in Lake Masoko A. calliptera in the context of the neighbouring Lake Malawi mega-radiation that comprises over 700 species. Conclusions: These results provide the first evidence of divergence in this often-overlooked sensory modality in the early stages of ecological speciation, suggesting that it may have a role in the broader adaptive radiation process
The development of compassionate engagement and action scales for self and others
Background Studies of the value of compassion on physical and mental health and social relationships have proliferated in the last 25 years. Although, there are several conceptualisations and measures of compassion, this study develops three new measures of compassion competencies derived from an evolutionary, motivational approach. The scales assess 1. the compassion we experience for others, 2. the compassion we experience from others, and 3. self-compassion based on a standard definition of compassion as a âsensitivity to suffering in self and others with a commitment to try to alleviate and prevent itâ. We explored these in relationship to other compassion scales, self-criticism, depression, anxiety, stress and well-being. Methods Participants from three different countries (UK, Portugal and USA) completed a range of scales including compassion for others, self-compassion, self-criticism, shame, depression, anxiety and stress with the newly developed âThe Compassionate Engagement and Actionsâ scale. Results All three scales have good validity. Interestingly, we found that the three orientations of compassion are only moderately correlated to one another (râ<â.5). We also found that some elements of self-compassion (e.g., being sensitive to, and moved by oneâs suffering) have a complex relationship with other attributes of compassion (e.g., empathy), and with depression, anxiety and stress. A path-analysis showed that self-compassion is a significant mediator of the association between self-reassurance and well-being, while self-criticism has a direct effect on depressive symptoms, not mediated by self-compassion. Discussion Compassion evolved from caring motivation and in humans is associated with a range of different socially intelligent competencies. Understanding how these competencies can be inhibited and facilitated is an important research endeavour. These new scales were designed to assess these competencies. Conclusions This is the first study to measure the three orientations of compassion derived from an evolutionary model of caring motivation with specified competencies. Our three new measures of compassion further indicate important complex relationships between different potentiationâs of compassion, well-being, and vulnerability to psychopathologies.N/
Cholinergic mechanisms in depression
Evidence supporting a cholinergic hypothesis of depression is presented. First, cholinergic overdrive produces behavioral, neuroendocrine, and polysomnographic features of melancholia, and melancholics exhibit state-independent supersensitivity to cholinergic overdrive. Drugs inducing up-regulation and supersensitivity of cholinergic systems produce behavioral, polysomnographic, and neuroendocrine effects of melancholia when withdrawn. These observations also implicate cholinergic system supersensitivity as a factor in the pathophysiology of certain affective disorders. Cholinergic and monoaminergic mechanisms reciprocally regulate drive-reduction, and substances of abuse either activate monoaminergic networks or antagonize cholinergic systems. These points are consistent with the hypothesis that dynamic interaction between cholinergic and monoaminergic systems is involved in the regulation of mood and affect. Finally, antimuscarinic agents have antidepressant effects. Thus, the hypothesis that supersensitivity of cholinergic systems is involved in the pathophysiology of affective disorders is supported by several lines of evidence. This evidence is reviewed; directions for future research and promising methods of investigation are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26059/1/0000133.pd
Psychological testing : an introduction, 2nd Ed./ Domino
xi, p. 517 hal. ; il. ; ind. ; 28 cm
Psychological testing : an introduction, 2nd Ed./ Domino
xi, p. 517 hal. ; ill. ; ind. ; 28 cm
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