Coupled stalagmite – Alluvial fan response to the 8.2 ka event and early Holocene palaeoclimate change in Greece

We explore the expression of early Holocene climatic change in the terrestrial Mediterranean of southern Greece. A regional palaeoclimate record from stable isotope and trace element geochemical proxies in an early Holocene (~12.4 ka to 6.7 ka) stalagmite is compared to the timing of palaeosol (entisol) development on an early Holocene alluvial fan located <100 km from the stalagmite site. Radiocarbon dated entisol development records fan abandonment surfaces, which can be coupled to the stalagmite climate signal. Variations in δ13C best record the main elements of palaeoclimatic change, more negative values indicating soil carbon input to karst groundwater under wetter conditions. The wettest conditions begin around 10.3 ka, coincident with the start of sapropel 1 deposition in the eastern Mediterranean. The widely documented northern hemisphere ‘8.2 ka event’ of cooler and drier conditions has a muted δ18O climatic signal in common with other stalagmite climate records from the wider Mediterranean. However, less negative δ13C values do record a period of episodic dryness between ~8.8 and ending at 8.2 ka. Wetter conditions re-established after 8.1 ka to the end of the record. The oldest alluvial fan entisols were developing by ~9.5 ka, and a prominent rubified entisol developed ~8.3 to 8.4 ka, indicating pedogenesis within dating error of the 8.2 ka event. The speleothem record of episodic dryness between ~8.8 and 8.2 ka, combined with other regional proxies, is consistent with the notion that precipitation patterns in Greece may have changed from predominantly winter frontal to summer convective during this period. Palaeosol formation on the alluvial fan may have been an allocyclic response to this change. It is plausible that fan-channel incision, driven by temporary development of a ‘flashier’ summer rainfall regime, isolated large areas of the fan surface allowing onset of prolonged pedogenesis there

Mild dehydration does not reduce postexercise appetite or energy intake

Purpose: It has now been established that exercise performed under various environmental conditions may affect acute energy intake and appetite-related hormones. The exact mechanism linking acute energy intake and exercise remains unknown, although indirect evidence suggests a possible role for hydration status. Therefore, the purpose of this study was to investigate the interaction of exercise and hydration status on subsequent energy intake and appetite-related hormones. Methods: In a randomized, counterbalanced design, 10 physically active males completed three experimental trials in a fasted state: exercise when hydrated (0%-1% of body mass), exercise when dehydrated (-1% to -2% of body mass), and a hydrated resting control. Exercise consisted of treadmill running for 45 min at 70% (V) over dotO(2peak). Participants were then given access to a buffet-style breakfast from which they could consume ad libitum. Blood was sampled regularly during trials for appetite-related hormones. Results: There were no significant differences in total energy intake between trials (P = 0.491); however, relative energy intake was significantly higher in the control (4839 +/- 415 kJ, P < 0.001) compared to hydrated (1749 +/- 403 kJ) and dehydrated exercise (1656 +/- 413 kJ) conditions. Exercise performed in a dehydrated state resulted in significantly lower concentrations of ghrelin compared with control (P = 0.045) and hydrated exercise conditions (P = 0.014). Conclusions: Exercise significantly decreased relative energy intake compared with resting control; however, energy intake (relative and total) was no different between the exercise conditions (dehydrated vs hydrated). Despite similar energy intake between trials, exercise in a dehydrated state resulted in a significantly lower concentration of ghrelin, a hormone responsible for stimulating appetite

Revisão do gênero Neotropical Myiotabanus Lutz (Diptera, Tabanidae) com descrição de uma espécie nova Revision of the Neotropical genus Myiotabanus Lutz (Diptera, Tabanidae) with description of a new species

O gênero Myiotabanus Lutz, 1928 é revisado. M. barrettoi Fairchild, 1969 e M. muscoideus (Hine, 1907) são redescritas de lectótipos (presente designação) e M. sarcophagoides Lutz, 1928 é redescrita do holótipo. M. amazonicus sp. nov. é descrita da bacia amazônica e do pantanal, Brasil, a partir da exuvia pupal e de quatro fêmeas adultas.<br>Three previously described and one new species are treated. M. amazonicus sp. nov. from the Brazilian Amazon Basin and the Pantanal is described from pupal exuvia and four adult females. M. barrettoi Fairchild, 1969 and M. muscoideus (Hine, 1907) are redescribed from lectotypes, here designated, and M. sarcophagoides Lutz, 1928 is redescribed from holotype. An illustrated key for female adults and for known pupae species are provided

The effective dielectric tensor for electromagnetic waves in inhomogeneous magnetized plasmas and the proper formulation in the electrostatic limit

Conduct disorder (CD) is a common and highly impairing psychiatric disorder that usually emerges in childhood or adolescence and is characterized by severe antisocial and aggressive behaviour. It frequently co-occurs with attention-deficit/hyperactivity disorder (ADHD) and often leads to antisocial personality disorder in adulthood. CD affects ~3% of school-aged children and is twice as prevalent in males than in females. This disorder can be subtyped according to age at onset (childhood-onset versus adolescent-onset) and the presence or absence of callous-unemotional traits (deficits in empathy and guilt). The aetiology of CD is complex, with contributions of both genetic and environmental risk factors and different forms of interplay among the two (gene–environment interaction and correlation). In addition, CD is associated with neurocognitive impairments; smaller grey matter volume in limbic regions such as the amygdala, insula and orbitofrontal cortex, and functional abnormalities in overlapping brain circuits responsible for emotion processing, emotion regulation and reinforcement-based decision-making have been reported. Lower hypothalamic–pituitary–adrenal axis and autonomic reactivity to stress has also been reported. Management of CD primarily involves parent-based or family-based psychosocial interventions, although stimulants and atypical antipsychotics are sometimes used, especially in individuals with comorbid ADHD