563 research outputs found

    Climate and oceanography of the Galapagos in the 21st century : expected changes and research needs

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    With the likelihood that carbon dioxide and other greenhouse-gas levels in the atmosphere will continue to increase for the next decades, and that the planet as a whole will likely warm as a result, we expect the oceanography and climate of the Galapagos to change. Based on an analysis of observational studies and climate models, the main changes are likely to include higher sea-surface temperatures, continued El Niño and La Niña events, some of which will be intense, a rise in sea level of several cm, increased precipitation, lower surface ocean pH, and a reduction in upwelling. These changes will likely alter the marine and terrestrial ecosystems of the Galapagos in ways that are difficult to predict. Major uncertainties exist concerning the relationship between the expected regional changes in ocean temperatures, precipitation, upwelling and seawater pH that most climate models consider, and the local changes in the Galapagos Islands

    Alexithymia: a general deficit of interoception

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    Alexithymia is a sub-clinical construct, traditionally characterized by difficulties identifying and describing one's own emotions. Despite the clear need for interoception (interpreting physical signals from the body) when identifying one's own emotions, little research has focused on the selectivity of this impairment. While it was originally assumed that the interoceptive deficit in alexithymia is specific to emotion, recent evidence suggests that alexithymia may also be associated with difficulties perceiving some non-affective interoceptive signals, such as one's heart rate. It is therefore possible that the impairment experienced by those with alexithymia is common to all aspects of interoception, such as interpreting signals of hunger, arousal, proprioception, tiredness and temperature. In order to determine whether alexithymia is associated with selectively impaired affective interoception, or general interoceptive impairment, we investigated the association between alexithymia and self-reported non-affective interoceptive ability, and the extent to which individuals perceive similarity between affective and non-affective states (both measured using questionnaires developed for the purpose of the current study), in both typical individuals (n = 105 (89 female), mean age = 27.5 years) and individuals reporting a diagnosis of a psychiatric condition (n = 103 (83 female), mean age = 31.3 years). Findings indicated that alexithymia was associated with poor non-affective interoception and increased perceived similarity between affective and non-affective states, in both the typical and clinical populations. We therefore suggest that rather than being specifically associated with affective impairment, alexithymia is better characterized by a general failure of interoception

    Age-related Effects on Social Cognition in Adults with Autism Spectrum Disorder: A Possible Protective Effect on Theory of Mind

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    Impaired social cognition has been suggested to underlie the social communication difficulties that define autism spectrum disorder (ASD). In typical development, social cognition may deteriorate in older age, but age effects in ASD adults have been little explored. In the present study, we compared groups of younger and older adults with and without ASD (n = 97), who completed a set of social cognition tasks assessing theory of mind (ToM), and self‐report measures of empathy and alexithymia. While typically developing (TD) younger adults outperformed elderly TD and younger ASD participants, younger and older ASD adults did not differ in their ToM performance, and the elderly ASD and TD groups performed equivalently. By contrast, ASD adults reported lower empathy scores and higher levels of alexithymia symptoms compared to TD adults regardless of age. The difference between ASD and TD groups in self‐reported empathy scores was no longer significant when alexithymia was covaried (with the exception of the Perspective Taking subscore). Results suggest a possible age‐protective effect on ToM in the ASD group. In addition, empathy difficulties appear to be associated with alexithymia rather than ASD per se. Possible interpretations are discussed, and future directions for autism aging research are proposed

    Psychometric properties of the Emotion Awareness Questionnaire for children

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    In order to broaden the alexithymia concept, we identified six aspects in a newly developed questionnaire for children which aims to measure emotion awareness: Differentiating Emotions, Verbal Sharing of Emotions, Bodily Awareness, Acting Out Emotions, Analyses of Emotions, and Others? Emotions. First, the six-factor structure of this Emotion Awareness Questionnaire was identified in children (692 children, 9-16 years old), although the scale Acting Out Emotions showed poor psychometric properties. Second, the predictive validity of the Emotion Awareness Questionnaire showed promise with respect to self-reported somatic complaints (in samples from two different countries, the UK and the Netherlands), depression and worry. Only Acting Out Emotions did not contribute to any of the criterion variables whilst Bodily Awareness and Others? Emotions contributed in the unexpected direction. It is proposed that the Emotion Awareness Questionnaire could help to identify which specific elements of emotional (dys)functioning are related to different kinds of psychological problems

    Tracing plant source water dynamics during drought by continuous transpiration measurements : An in-situ stable isotope approach

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    Publisher Copyright: © 2022 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.The isotopic composition of xylem water (δX) is of considerable interest for plant source water studies. In-situ monitored isotopic composition of transpired water (δT) could provide a nondestructive proxy for δX-values. Using flow-through leaf chambers, we monitored 2-hourly δT-dynamics in two tropical plant species, one canopy-forming tree and one understory herbaceous species. In an enclosed rainforest (Biosphere 2), we observed δT-dynamics in response to an experimental severe drought, followed by a 2H deep-water pulse applied belowground before starting regular rain. We also sampled branches to obtain δX-values from cryogenic vacuum extraction (CVE). Daily flux-weighted δ18OT-values were a good proxy for δ18OX-values under well-watered and drought conditions that matched the rainforest's water source. Transpiration-derived δ18OX-values were mostly lower than CVE-derived values. Transpiration-derived δ2HX-values were relatively high compared to source water and consistently higher than CVE-derived values during drought. Tracing the 2H deep-water pulse in real-time showed distinct water uptake and transport responses: a fast and strong contribution of deep water to canopy tree transpiration contrasting with a slow and limited contribution to understory species transpiration. Thus, the in-situ transpiration method is a promising tool to capture rapid dynamics in plant water uptake and use by both woody and nonwoody species.Peer reviewe

    Chiral monoterpenes reveal forest emission mechanisms and drought responses

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    Monoterpenes (C10H16) are emitted in large quantities by vegetation to the atmosphere (>100 TgC year−1), where they readily react with hydroxyl radicals and ozone to form new particles and, hence, clouds, affecting the Earth’s radiative budget and, thereby, climate change1,2,3. Although most monoterpenes exist in two chiral mirror-image forms termed enantiomers, these (+) and (−) forms are rarely distinguished in measurement or modelling studies4,5,6. Therefore, the individual formation pathways of monoterpene enantiomers in plants and their ecological functions are poorly understood. Here we present enantiomerically separated atmospheric monoterpene and isoprene data from an enclosed tropical rainforest ecosystem in the absence of ultraviolet light and atmospheric oxidation chemistry, during a four-month controlled drought and rewetting experiment7. Surprisingly, the emitted enantiomers showed distinct diel emission peaks, which responded differently to progressive drying. Isotopic labelling established that vegetation emitted mainly de novo-synthesized (−)-α-pinene, whereas (+)-α-pinene was emitted from storage pools. As drought progressed, the source of (−)-α-pinene emissions shifted to storage pools, favouring cloud formation. Pre-drought mixing ratios of both α-pinene enantiomers correlated better with other monoterpenes than with each other, indicating different enzymatic controls. These results show that enantiomeric distribution is key to understanding the underlying processes driving monoterpene emissions from forest ecosystems and predicting atmospheric feedbacks in response to climate change

    Alexithymia explains increased empathic personal distress in individuals with and without eating disorders

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    It is often assumed that empathy impairments are common in individuals with eating disorders (EDs), but empirical work has been limited and produced mixed results, making the clinical features and treatment needs of this population difficult to determine. Alexithymia, characterised by difficulties identifying and describing one’s own emotions, frequently co-occurs with EDs, and is associated with atypical recognition of, and empathy for, others’ emotions. The current study used an existing empathy for pain paradigm to determine whether atypical empathy in EDs stems from co-occurring alexithymia, rather than EDs per se. Empathy (specifically personal distress in response to others’ pain) was assessed in individuals with EDs (N = 21) and an alexithymia-matched control group (N = 22). Participants were simultaneously members of a high alexithymia (N = 16) or low alexithymia (N = 27) group, allowing the independent contributions of alexithymia and EDs to be determined. Participants judged the laterality of hands and feet in painful and non-painful situations, and the degree of empathic interference on RTs was measured. Results indicated that observation of painful stimuli impacted task performance in those with high levels of alexithymia more than those with low levels, but no effect of ED diagnosis was observed. These findings suggest that co-occurring alexithymia explains increased empathic personal distress in ED populations. Atypical empathy may therefore not be a core feature of EDs, and interventions aimed at improving empathy-related social functioning may only be necessary for patients who also have alexithymia. These findings emphasise the importance of determining the influence of co-occurring alexithymia when assessing empathy in clinical populations

    The intrafamilial transmission of rheumatoid arthritis--V : Differences between rheumatoid arthritics and controls on selected personality variables

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    This study describes the differences between adult rheumatoid arthritics (RA's) and controls on a number of personality variables. The cases come both from a national interview sample and a university arthritis clinic, while the controls were part of a cluster which included the spouse of the RA, the RA's sib and his (her) spouse, a cousin of the RA, and an unrelated individual. The data were collected in the course of three structured interviews. The major findings were the following: 1. (1) RA's of both sexes score higher on several measures of poor mental health than the non-RA's. For the women, these differences are stronger and involve more diverse aspects of poor mental health.2. (2) Women with RA report more frequent anger-irritation and more frequent impulses to overt aggression than women without RA. Involved in these differences are scales reflecting both general anger-aggression and that which is directed at the husband.3. (3) Men with RA, compared with healthy men, report less frequent impulses to general overt aggression, less wife-directed aggression, stronger guilt about such aggression, and their anger episodes were of longer duration.4. (4) When a difference score was computed between two scales, frequency of impulses to overt aggression and frequency of actual aggressive acts, women with RA, compared with healthy women, showed stronger control over the expression of such impulses, but seemed unable to apply the control to all types of aggressive impulses equally.5. (5) Women with RA were unduly frequently found above median on `guilt about spouse-directed aggression' and above median on several measures of husband directed anger-aggression. It was suggested that this might indicate greater conflict among the RA women.6. (6) Comparing general and spouse-specific measures of overt aggression, (a) women with RA `preferred' to direct their aggression at their husbands more than healthy women; while (b) men with RA `avoided' directing their aggression at their wives more often than healthy men.7. (7) When husbands' self-reports of wife-directed anger-aggression were correlated with wives' self-reports of husband-directed anger-aggression, the associations were positive and moderate to strong.8. (8) Marriages of RA wives and healthy husbands were highest on mutually directed anger-aggression; marriages of RA husbands and healthy wives were the lowest, while the healthy husbands-healthy wives marriages were intermediate.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32908/1/0000288.pd

    Leaf-level metabolic changes in response to drought affect daytime CO2 emission and isoprenoid synthesis pathways

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    In the near future, climate change will cause enhanced frequency and/or severity of droughts in terrestrial ecosystems, including tropical forests. Drought responses by tropical trees may affect their carbon use, including production of volatile organic compounds (VOCs), with implications for carbon cycling and atmospheric chemistry that are challenging to predict. It remains unclear how metabolic adjustments by mature tropical trees in response to drought will affect their carbon fluxes associated with daytime CO2 production and VOC emission. To address this gap, we used position-specific 13C-pyruvate labeling to investigate leaf CO2 and VOC fluxes from four tropical species before and during a controlled drought in the enclosed rainforest of Biosphere 2 (B2). Overall, plants that were more drought-sensitive had greater reductions in daytime CO2 production. Although daytime CO2 production was always dominated by non-mitochondrial processes, the relative contribution of CO2 from the tricarboxylic acid cycle tended to increase under drought. A notable exception was the legume tree Clitoria fairchildiana R.A. Howard, which had less anabolic CO2 production than the other species even under pre-drought conditions, perhaps due to more efficient refixation of CO2 and anaplerotic use for amino acid synthesis. The C. fairchildiana was also the only species to allocate detectable amounts of 13C label to VOCs and was a major source of VOCs in B2. In C. fairchildiana leaves, our data indicate that intermediates from the mevalonic acid (MVA) pathway are used to produce the volatile monoterpene trans-β-ocimene, but not isoprene. This apparent crosstalk between the MVA and methylerythritol phosphate pathways for monoterpene synthesis declined with drought. Finally, although trans-β-ocimene emissions increased under drought, it was increasingly sourced from stored intermediates and not de novo synthesis. Unique metabolic responses of legumes may play a disproportionate role in the overall changes in daytime CO2 and VOC fluxes in tropical forests experiencing drought
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