Neuropsychiatry of creativity.

In this paper, we review in brief the development of ideas that over time have tried to explain why some individuals are more creative than others and what may be the neurobiological links underlying artistic creativity. We note associations with another unique human idea, that of genius. In particular, we discuss frontotemporal dementia and bipolar, cyclothymic mood disorder as clinical conditions that are helping to unravel the underlying neuroanatomy and neurochemistry of human creativity. This article is part of a Special Issue entitled "Epilepsy, Art, and Creativity"

Bounds for the global cyclicity index of a general network via weighted majorization

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Betweenness Centrality: Extremal Values and Structural Properties

In this paper we investigate the structural properties of betweenness centrality and determine some cases in which betweenness reaches its extremal values. Special attention is paid to Star(G), the set of vertices adjacent to all other vertices in a graph and we prove several results about the betweenness of the elements of this set. We introduce the new concept of total betweenness and relate it to group betweenness. We prove a necessary and sufficient condition for the two measures to coincide. Next we consider cutsets and cutvertices and we find a lower bound for their betweenness; in particular for a cutvertex this lower bound is the cutting number. Finally we apply the previous results to trees, proving an alternative formula for betweenness based on cutvertex properties

Extending assortativity: An application to weighted social networks

Assortativity by degree for complex networks is quantified by the Newman coefficient, and it describes a tendency for nodes to be connected to others with a similar degree. A generalization of the assortativity index has been proposed in the literature for undirected and unweighted networks, analysing the correlation between vertices that are not necessarily adjacent, but connected through paths, shortest paths and random walks. The aim of this study is to define a new class of higher-order assortativity measures for weighted networks. The effectiveness of these measures is evident in social networks, where both weights and connections are significant. Applications to Facebook and co-authorship networks are provided, analysing the assortativity beyond the nearest neighbours

Patterned copper sulfide thin films: A method for studying leaching behaviour

An experimental study on copper leaching from Cu1.85S thin films is presented, wherein copper extraction is quantitatively evaluated by changes in film thickness measured by white light interferometric profilometry. Changes in the film morphology and elemental composition, as assessed by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, are used to confirm that the loss in film thickness is due to changes in the copper content and that the resultant film species is consistent with the mechanism of copper dissolution. The Cu1.85S thin films were synthesized by chemical bath deposition. The leaching behaviour of copper from the films was investigated in acidic ferric sulfate media at pHs 1, 2, and 3, and pH 1 at redox potentials of ∼350-650mV versus Ag/AgCl in 3M KCl. The changes in the film thickness and copper sulfur ratio were shown to reflect copper dissolution behaviour from chalcocite. Leaching of the Cu1.85S films demonstrated a greater decrease in film thickness as pH decreased. In addition comparison of the order of reaction as a function of proton concentration in non-oxidative dissolution of Cu1.85S (0.06) and as a function of iron(iii) concentration in ferric oxidation of Cu1.85S (0.40) shows that the proton dissolution reaction is negligible. Leaching of the Cu1.85S films at redox potentials of up to ∼476.4mV versus Ag/AgCl in 3M KCl produced covellite and demonstrated greater decreases in film thickness with increases in the redox potential. Leaching of the films above ∼476.4mV resulted in the formation of spionkopite and demonstrated a much lesser decrease in film thickness. These results are consistent with Eh-pH diagrams for the Cu-S-H2O system

Inflammatory cytokines in fracture healing: involvement and analysis

IntroductionThe importance of the interplay of both skeletal and immune systems is reflected by the emerging interdisciplinary research field, called osteoimmunology, focused on common aspects of osteology and immunology. Many segnaling molecules, such as transcription factors, membrane receptors, IL-6 and TNF-α, are involved in the bone remodelling. The purpose of this study was to evaluate markers of bone metabolism and cytokines in patients with fragility fractures compared to osteoporotic patients. Materials and methods We enrolled 37 subjects with a femoral neck fracture and 47osteoporotic outpatients . Blood samples are drawing 24h before and after surgery (Group A) and at the first examination for outpatients (Group B). All the patients underwent DEXA examination (T-score <-2.5) to measure BMD. For bone metabolism were measured Ca, P, vitamin D, PTH, CTX, ALP and osteocalcin using ECL technology (Modular E, Roche, Basel, Switzerland). IL-1, IL-6, TNF-α and IL-10 concentrations were evaluated by ELISA assay (R&D Systems, Inc. Minneapolis, USA). Statistical analysis were performed using t-test. Results Statistical differences were observed in vitamin D, PTH and CTX concentrations. Group A showed a decrease in Vitamin D (p<0.001) whereas PTH and CTX were increase (p≤ 0.001). About cytokine concentrations Group A (before surgery) showed a significant increase in IL-6, TNF-α and IL-10 (respectively p<0.0001, p<0.0001 and p=0.01) respect Group B. The different implant used lead to a change, IL-6 and IL-10 increased after surgery in intramedullary nail patients Vs prosthesis, significant difference were respectively p<0.001 and p<0.05. Discussion The inflammatory mediators are involved not only in several aspects of physiological bone remodeling but also in pathological bone disorders. The higher cytokines levels observed in fractured patients suggest an inflammatory condition which lead to bone weakness, this hypothesis may be supported by the results obtained in Vitamin D, PTH and CTX (1). The results obtained in surgery treatment with prosthesis give a reduction in systemic cytokines concentrations. Inflammatory cytokines could be used to identify high-risk fracture patients, further study need to confirm their role in fracture healing. 1)Lacativa PG, Farias ML. Osteoporosis and inflammation. Arq Bras Endocrinol Metabol. 2010 Mar;54(2):123-32 2) Pacifici R. The immune system and bone. Arch Biochem Biophys. 2010 Jun 1

Cefalee primarie:aspetti patogenetici

Le cefalee primarie sono patologie complesse, altamente disabilitanti. La fisiopatologia del dolore è comune a tutte le forme di cefalea primaria e trova il suo correlato neurobiologico nel sistema trigeminovascolare. Le strette correlazioni fra tale sistema e altre aree del troncoencefalo e della corteccia determinano molti aspetti della sintomatologia correlata al dolore cefalico nelle diverse forme di cefalea. L’emicrania e la cefalea a grappolo così come altre cefalee autonomiche trigeminali (TACs) hanno molti aspetti fisiopatologici comuni e sono considerate cefalee neurovascolari. Non esiste a tutt’oggi una teoria unificante sulla fisiopatologia delle cefalee primarie. La complessità del quadro sintomatologico suggerisce che in soggetti geneticamente predisposti, una disfunzione del troncoencefalo e di alcune aree corticali sia responsabile dell’attivazione nocicettiva nonchè di una facilitazione delle informazioni nocicettive delle strutture craniche innervate dal trigemino e responsabile della sensazione dolorosa che nell’uomo è la cefalea.Primary headaches are complex and highly disabling disorders. Pathophysiology of pain is shared by all types of primary headaches and the neurobiological correlate is the trigeminovascular system. Bidirectional connections between trigeminovascular system and key structures of brainstem as well as cortex of human brain may explain the majority of symptoms observed in migraine and other headaches. Migraine and cluster headache as well as other trigeminal autonomic cephalalgias(TACs) are considered neurovascular headaches.The complex picture of symptoms in primary headaches suggests that, in genetically susceptible patients, a primary disfunction of brainstem and other cortical areas is responsible of activation and facilitation of nociceptive informations from cranial structures innervated by trigeminal nerve that, finally, determines the cephalic pain called headache in humans