Three-dimensional coherent X-ray diffraction imaging of a ceramic nanofoam: determination of structural deformation mechanisms

Ultra-low density polymers, metals, and ceramic nanofoams are valued for their high strength-to-weight ratio, high surface area and insulating properties ascribed to their structural geometry. We obtain the labrynthine internal structure of a tantalum oxide nanofoam by X-ray diffractive imaging. Finite element analysis from the structure reveals mechanical properties consistent with bulk samples and with a diffusion limited cluster aggregation model, while excess mass on the nodes discounts the dangling fragments hypothesis of percolation theory.Comment: 8 pages, 5 figures, 30 reference

Multisensory Logic of Infant-Directed Aggression by Males

Newborn mice emit signals that promote parenting from mothers and fathers but trigger aggressive responses from virgin males. Although pup-directed attacks by males require vomeronasal function, the specific infant cues that elicit this behavior are unknown. We developed a behavioral paradigm based on reconstituted pup cues and showed that discrete infant morphological features combined with salivary chemosignals elicit robust male aggression. Seven vomeronasal receptors were identified based on infant-mediated activity, and the involvement of two receptors, Vmn2r65 and Vmn2r88, in infant-directed aggression was demonstrated by genetic deletion. Using the activation of these receptors as readouts for biochemical fractionation, we isolated two pheromonal compounds, the submandibular gland protein C and hemoglobins. Unexpectedly, none of the identified vomeronasal receptors and associated cues were specific to pups. Thus, infant-mediated aggression by virgin males relies on the recognition of pup's physical traits in addition to parental and infant chemical cues

Neurocisticercose e síndrome de lennox-gastaut: relato de caso Neurocysticercosis and Lennox-Gastaut syndrome: case report

Relata-se o caso de uma menina que, aos 2 anos de idade, apresentou a forma epiléptica, hidrocefálica e encefalítica da neurocisticercose, diagnosticada por exame do líquido cefalorraqueano e tomografia computadorizada de crânio, evolução com crises polimórficas, episódios de descompensação da hipertensão intracraniana por obstrução do sistema de derivação ventriculoperitoneal, retardo no desenvolvimento neuropsicomotor e cegueira até que, aos 10 anos de idade, foi diagnosticada síndrome de Lennox-Gastaut. Atualmente, a paciente tem 16 anos, apresenta sequelas neurológicas e crises parciais complexas com automatismos, parcialmente controladas com o uso de clobazan e oxcarbazepina. A primeira associação de neurocisticercose e síndrome de Lennox-Gastaut foi descrita em 1973, por Frochtengarten & Scarante, em uma menina com quadro clínico semelhante ao do caso relatado.<br>Report of a girl with the epileptic, hydrocephalic and encephalitic form of neurocysticercosis, diagnosed by cerebrospinal flui and computed tomography exams, during her second year of life and an evolution with multiple types of seizures, prolonged periods of intracranial hypertension due to obstruction in the ventriculoperitoneal shunt, psicomotor regression and blindness until she was 10 years old, when the Lennox-Gastaut syndrome was diagnosed. Nowadays the patient is 16 years old and presents complex partial seizures with automatism not completely controlled with clobazan and oxcarbazepine, associated to left spastic hemiparesis, universal hyperreflexia, psychomotor agitation, self-mutilation, amaurosis and severe mental retardation. The association between neurocysticercosis and Lennox-Gastaut syndrome was first described in 1973 by Frochtengarten & Scarante in a Brazilian girl with a similar clinical picture