A geometrical instability for ultra-light fields during inflation?

Westudythebehaviourofisocurvatureperturbationsinnon-linearsigmamodels which naturally emerge in supergravity and string inflationary scenarios. We focus on the case of negatively curved field manifolds which can potentially lead to a geometrical destabilisation of isocurvature modes. We find however that heavy fields are stable when their effective mass is computed on the attractor background solution. On the other hand, we show that ultra-light fields can potentially suffer from a geometrical instability when the background trajectory is a geodesic in field space. In this case a full understanding of the system is likely to require the use of non-perturbative methods.Comment: Matches published version, 5 pages, 2 figure

Metacognition and headache: which Is the role in childhood and adolescence?

Headache, in particular migraine, is one of the most frequent neurological symptoms in children and adolescents and it affects about 60% of children and adolescents all over the world. Headache can affect several areas of child’s functioning, such as school, physical activities, peer, and family relationship. The global and severe burden of this disease requires a multidisciplinary strategy and an effective treatment addressed all of the patient’s needs and based on cutting-edge scientific research. In recent years, research has focused on cognitive factors specifically in functions called metacognitive processes. Metacognition can be defined as the knowledge, beliefs, and cognitive processes involved in monitoring, control, and assessment of cognition. Metacognition seems to be closely related to the ability of theory of mind, the ability to infer, and reason about the mental states of other people in order to predict and explain own behavior. Recent studies found a relationship between metacognitive skills and anxiety, depression, motivation, academic performance, human social interactions, and stress symptoms. This relationship is very interesting for headache treatment, because these factors are the most commonly reported triggers in this disorder and there is a high comorbidity with anxiety and depression in children and adolescents with headache. So, headache and these comorbidities, in particular anxiety and depression, may have in common persistent and maladaptive patterns of thinking which are related to maladaptive metacognitive beliefs. Further research should assess metacognitive processes of children and adolescents with headache in order to increase their ability to control their own cognitive processes and consequently monitor factors which may trigger the attacks

Headache and alexithymia in children and adolescents: what Is the connection?

Background: Headache is one of the most common complaints in children and adolescents and comorbidity rates are very high and the major associated diseases are depression, anxiety, atopic disorders, sleep, and behavioral disorders. In recent years, it has been highlighted that difficulties regulating emotions such as alexithymia have also been associated with diagnosis of somatization. Methods: We carried out a mini review analyzing the relation between alexithymia and primary headache (e.g., migraine and tension type headache) in children and adolescents by synthesizing the relevant studies in the literature on PubMed, PsycINFO, and Google Scholar. Search terms were "alexithymia" combined with the "primary headache," "migraine," "tension type headache," "children," and "adolescents." Results: All analyzed studies found higher levels of alexithymia in children and adolescents with headache than control groups but there are different opinions about the relationship between headache and alexithymia. For example, some studies suggest that the association between headache and alexithymia in children may be due to an incomplete development of emotive competency or a general immature cognitive development, instead other studies found a correlation between headache symptoms, insecure attachment, and alexithymia. There seems to be also differences between children with migraine compared to those with tension type headache (TTH). Conclusion: There are some studies on adults suffering from headache or migraine and alexithymia, but there is only a moderate amount of research on pediatric age with different opinions and theories about this relationship. Further studies on children and adolescents are necessary to effectively understand this relationship and to help children to reduce headache and improve emotional consciousness

Don't judge a book by its cover. factitious disorder imposed on children-report on 2 cases

Factitious Disorder Imposed on Another (FDIA), also known as Munchausen Syndrome by Proxy (MSbP) is a very serious form of child abuse. The perpetrator, usually the mother, invents symptoms or causes real ones in order to make her child appear sick. Usually this is due to a maladaptive disorder or to an excessive of attention-seeking on her part. We report here two new cases of FDIA. The first one is a 9-year-old boy with a history of convulsive episodes, reduced verbal production, mild psychomotor disorder and urological problems who underwent several invasive procedures and hospitalizations before a diagnosis of FDIA was made. The second is a 12 year-old girl with headache, abdominal pain, lipothymic episodes, seizures and a gait impairment, who was hospitalized in several hospitals before an FDIA was diagnosed

Dispersal of larval and juvenile seabream: Implications for Mediterranean marine protected areas

In the marine context, information about dispersal is essential for the design of networks of marine protected areas (MPAs). Generally, most of the dispersal of demersal fishes is thought to be driven by the transport of eggs and larvae in currents, with the potential contribution of dispersal in later life stages relatively minimal.Using otolith chemistry analyses, we estimate dispersal patterns across a spatial scale of approximately 180. km at both propagule (i.e. eggs and larvae) and juvenile (i.e. between settlement and recruitment) stages of a Mediterranean coastal fishery species, the two-banded seabream Diplodus vulgaris. We detected three major natal sources of propagules replenishing local populations in the entire study area, suggesting that propagule dispersal distance extends to at least 90. km. For the juvenile stage, we detected dispersal of up to 165. km. Our work highlights the surprising and significant role of dispersal during the juvenile life stages as an important mechanism connecting populations. Such new insights are crucial for creating effective management strategies (e.g. MPAs and MPA networks) and to gain support from policymakers and stakeholders, highlighting that MPA benefits can extend well beyond MPA borders, and not only via dispersal of eggs and larvae, but also through movement by juveniles

Clinical survey of neurosensory side-effects of mandibular parasymphyseal bone harvesting

The aim of the present survey was to assess neurosensory disturbances and/or tooth-pulp sensitivity losses after mandibular parasymphyseal bone-harvesting procedures. Twenty-eight harvesting areas in 16 patients were surveyed. Mucosal and skin sensitivity of the chin/lower lip, divided into four regions, were determined via Pointed-Blunt and Two-Point-Discrimination Tests. Pulp sensitivity of the mandibular teeth from the left second bicuspid to the right second bicuspid was tested by cold vitality preoperatively and 12 months postoperatively. Teeth were grouped according to sensitivity alterations and distance from the harvesting defects, as measured on CT scans, and statistically significant differences sought. At 12 months, 29% of preoperatively vital cuspids overlying the harvesting defects revealed pulp-sensitivity losses; no patient reported anaesthesia or analgesia; hypoaesthesia was present in 4% (8 sites; 2 patients), hypoalgesia was present in 3% (5 sites; 2 patients) and Two-Point-Discrimination Tests yielded pathologic responses in 5% of tested areas (10 sites; 4 patients). Teeth with and without pulp sensitivity changes were statistically indistinguishable regarding distances between root apices or mental foramen and the harvesting defect. The loss of pulp sensitivity in any tooth cannot be predicted simply on the basis of the distance between its apex and the harvesting osteotomy line