262 research outputs found

    Climatic and pedoclimatic factors driving C and N dynamics in soil and surface water in the alpine tundra (NW-Italian Alps)

    Get PDF
    In alpine tundra the interannual and seasonal variability of C and N forms in soil and lake water during the short snow-free season could be significant and related to climatic and pedoclimatic variables. The hypothesis that not only the climatic and pedoclimatic parameters recorded during the summer season but also the ones measured during the previous snow-covered season could contribute to explaining the C and N dynamics in soil and surface water was tested along 10 snow-free seasons in 3 sites in the alpine tundra in the north-western Italian Alps (LTER site Istituto Mosso). Among the considered parameters, the snow cover duration (SCD) exerted a primary control on soil N-NH4+, DOC, Cmicr, Nmicr and DOC:DON ratio, with an inverse relationship. A long SCD might cause the consumption of all the subnival substrata by the soil microorganisms, determining a C starvation during the subsequent snow-free season. An opposite trend was observed for the lake water, where a longer SCD corresponded to a higher content of inorganic N forms. Among the pedoclimatic indices, the number of soil freeze/thaw cycles (FTC) recorded during the snow-covered season had a positive relation with most of soil C and N forms and N-NO3− in lake water. Only the soil DON showed an inverse pattern, and this result is consistent with the hypothesis that FTC released soil DON, subsequently decomposed and mineralized. Only N-NO3− had a significant intraseasonal variability, reaching the highest values in September both in soil and water, revealing a significant slowdown of the contribution of soil N immobilization processes

    Increased facial asymmetry in focal epilepsies associated with unilateral lesions

    Get PDF
    The epilepsies are now conceptualized as network disruptions: focal epilepsies are considered to have network alterations in the hemisphere of seizure onset, whilst generalized epilepsies are considered to have bi-hemispheric network changes. Increasingly, many epilepsies are also considered to be neurodevelopmental disorders, with early changes in the brain underpinning seizure biology. The development of the structure of the face is influenced by complex molecular interactions between surface ectoderm and underlying developing forebrain and neural crest cells. This influence is likely to continue postnatally, given the evidence of facial growth changes over time in humans until at least 18 years of age. In this case–control study, we hypothesized that people with lateralized focal epilepsies (i.e. unilateral network changes) have an increased degree of facial asymmetry, compared with people with generalized epilepsies or controls without epilepsy. We applied three-dimensional stereophotogrammetry and dense surface models to evaluate facial asymmetry in people with epilepsy, aiming to generate new tools to explore pathophysiological mechanisms in epilepsy. We analysed neuroimaging data to explore the correlation between face and brain asymmetry. We consecutively recruited 859 people with epilepsy attending the epilepsy clinics at a tertiary referral centre. We used dense surface modelling of the full face and signature analyses of three-dimensional facial photographs to analyse facial differences between 378 cases and 205 healthy controls. Neuroimaging around the time of the facial photograph was available for 234 cases. We computed the brain asymmetry index between contralateral regions. Cases with focal symptomatic epilepsy associated with unilateral lesions showed greater facial asymmetry compared to controls (P = 0.0001, two-sample t-test). This finding was confirmed by linear regression analysis after controlling for age and gender. We also found a significant correlation between duration of illness and the brain asymmetry index of total average cortical thickness (r = −0.19, P = 0.0075) but not for total average surface area (r = 0.06, P = 0.3968). There was no significant correlation between facial asymmetry and asymmetry of regional cortical thickness or surface area. We propose that the greater facial asymmetry in cases with focal epilepsy caused by unilateral abnormality might be explained by early unilateral network disruption, and that this is independent of underlying brain asymmetry. Three-dimensional stereophotogrammetry and dense surface modelling are a novel powerful phenotyping tool in epilepsy that may permit greater understanding of pathophysiology in epilepsy, and generate further insights into the development of cerebral networks underlying epilepsy, and the genetics of facial and neural development

    "A little theatrical but mostly athletic": The mutable erotics of Miranda July's The First Bad Man

    Get PDF
    By attending to the inherent flux of sexual fantasy, Miranda July’s first novel The First Bad Man reveals a mobile and mutable erotics capable of generating an enlarged range of self-identification and relational intimacy, far from any essentialist assumptions of stable or coherent sexual identity. July focuses specifically upon role-play as the means to unpack the normative categories of hetero/homosexuality, masculinity and femininity, celebrating rather than pathologising qualities like superficiality and inconsistency. The novel touches upon many polarising issues (for example, sexual violence, sadomasochism and assisted reproductive technology), deftly avoiding the conventional language which colours perception. Both erotic and humorous, The First Bad Man helps to redefine the often highly charged discourse around sex and sexuality

    Postictal Psychosis in Epilepsy: A Clinicogenetic Study

    Get PDF
    OBJECTIVE: Psychoses affecting people with epilepsy increase disease burden and diminish quality of life. We characterised post-ictal psychosis, which comprises about one-quarter of epilepsy-related psychoses, and has unknown causation. METHODS: We conducted a case-control cohort study including patients diagnosed with post-ictal psychosis, confirmed by psychiatric assessment, with available data regarding epilepsy, treatment, psychiatric history, psychosis profile and outcomes. After screening 3,288 epilepsy patients, we identified 83 with psychosis: 49 had post-ictal psychosis. Controls were 98 adults, matched by age and epilepsy type, with no history of psychosis. Logistic regression was used to investigate clinical factors associated with post-ictal psychosis; univariate associations with a P-value<0.20 were used to build a multivariate model. Polygenic risk scores for schizophrenia were calculated. RESULTS: Cases were more likely to have seizure clustering (OR 7.59, P<0.001), seizures with a recollected aura (OR 2.49, P=0.013) and a family history of psychiatric disease (OR 5.17, P=0.022). Cases showed predominance of right temporal epileptiform discharges (OR 4.87, P=0.007). There was no difference in epilepsy duration, neuroimaging findings or anti-seizure treatment between cases and controls. Polygenic risk scores for schizophrenia in an extended cohort of post-ictal psychosis cases (58) were significantly higher than in 1,366 epilepsy controls (R2 =3%, P=6x10-3 ), but not significantly different from 945 independent patients with schizophrenia (R2 =0.1%, P=0.775). INTERPRETATION: Post-ictal psychosis occurs under particular circumstances in people with epilepsy with a heightened genetic predisposition to schizophrenia, illustrating how disease biology (seizures) and trait susceptibility (schizophrenia) may interact to produce particular outcomes (post-ictal psychosis) in a common disease

    K.VitaÂź: a feasibility study of a blend of medium chain triglycerides to manage drug-resistant epilepsy

    Get PDF
    This prospective open-label feasibility study aimed to evaluate acceptability, tolerability and compliance with dietary intervention with K.Vita, a medical food containing a unique ratio of decanoic acid to octanoic acid, in individuals with drug-resistant epilepsy. Adults and children aged 3–18 years with drug-resistant epilepsy took K.Vita daily whilst limiting high-refined sugar food and beverages. K.Vita was introduced incrementally with the aim of achieving ≀35% energy requirements for children or 240 ml for adults. Primary outcome measures were assessed by study completion, participant diary, acceptability questionnaire and K.Vita intake. Reduction in seizures or paroxysmal events was a secondary outcome. 23/35 (66%) children and 18/26 (69%) adults completed the study; completion rates were higher when K.Vita was introduced more gradually. Gastrointestinal disturbances were the primary reason for discontinuation, but symptoms were similar to those reported from ketogenic diets and incidence decreased over time. At least three-quarters of participants/caregivers reported favourably on sensory attributes of K.Vita, such as taste, texture and appearance, and ease of use. Adults achieved a median intake of 240 ml K.Vita, and children 120 ml (19% daily energy). Three children and one adult had ß-hydroxybutyrate >1 mmol/l. There was 50% (95% CI 39–61%) reduction in mean frequency of seizures/events. Reduction in seizures or paroxysmal events correlated significantly with blood concentrations of medium chain fatty acids (C10 and C8) but not ß-hydroxybutyrate. K.Vita was well accepted and tolerated. Side effects were mild and resolved with dietetic support. Individuals who completed the study complied with K.Vita and additional dietary modifications. Dietary intervention had a beneficial effect on frequency of seizures or paroxysmal events, despite absent or very low levels of ketosis. We suggest that K.Vita may be valuable to those with drug-resistant epilepsy, particularly those who cannot tolerate or do not have access to ketogenic diets, and may allow for more liberal dietary intake compared to ketogenic diets, with mechanisms of action perhaps unrelated to ketosis. Further studies of effectiveness of K.Vita are warranted
    • 

    corecore