An evaluation of fibrous structure and physical characteristics of Cutia nut (Couepia edulis Prance) shell

The Cutia-nut (Couepia edulis Prance), a species originally from the Amazon region, has a kernel with reasonable nutritional value and a hard and thick woody shell that constitute most of the fruit. After the kernel removal, the shells are regarded as waste. The possibility of using such shells, as raw material for burning or charcoal production, as well as milled residue for structural reinforcement materials is quite feasible, considering environmental and economical aspects. There is, however, a complete lack of characterization of the Cutia-nut shell and other similar species which can aggregate desirable qualities for application as engineering material. In this study some analyses are presented aiming at providing information for potential uses of these residues. In general, the shells follow a regular shape with certain dimensional proportionality to the kernel. The shell is a fibrous material with high lignin content, present low water absorption and high resistance to natural degradation

Effect of thermocycling on the bond strength of a glass-infiltrated ceramic and a resin luting cement Efeito da ciclagem térmica sobre a resistência de união entre uma cerâmica infiltrada com vidro e um cimento resinoso

The aim of the present study was to evaluate the effect of thermocycling on the bond strength between the surface of the glass-infiltrated alumina ceramic In-Ceram (VITA) and the Panavia F resin cement (Kuraray CO.). Four 5x6x6mm In-Ceram blocks were obtained. One of the 6x6mm faces of each block was conditioned with Cojet - System (tribochemical silica coating, ESPE-3M) and then luted under a constant 750g pressure with Panavia F cement to another identical face of a resin composit block (Clearfil AP-X, Kuraray) obtained by reproduction of the ceramic one from Express (3M) addition curing silicone impressions. The four sets so formed by ceramic, luting cement and resin have been each one serially sectioned in 20 sticks so that the adhesive surface in each presented 1mm² of area. The samples were divided in 2 groups (n=10): G1- stored for 7 days in deionized water at 36 ± 2ºC; G2 - thermocycled 1500 times between 5 and 55ºC dwell times. The microtensile tests were accomplished in an universal testing machine (EMIC) at a crosshead speed of 0,5 mm/min. The results showed that the mean tensile bond strength values (MPa) for the group G2: (22,815 ± 5,254) had not statistically differ of the values of group G1: (25,628 ± 3,353) (t = 1,427; gl = 18; p-value = 0,171), at the level of a= 5%. It can be concluded that the thermocycling technique used in the present experiment had not produced statistically significant differences between the bond strength results of the specimens obtained by the two used techniques.<br>O objetivo deste estudo foi avaliar o efeito da ciclagem térmica sobre a resistência de adesão entre a superfície da cerâmica In-Ceram Alumina (VITA) e o cimento resinoso Panavia F (Kuraray). Foram confeccionados quatro blocos de cerâmica In-Ceram com dimensões de 5x6x6mm. Uma das faces com 6x6mm de cada bloco cerâmico, após condicionamento com o sistema Cojet (ESPE-3M) (jateamento com óxido de alumínio/jateamento com óxido de sílica/ silanização) foi cimentada com Panavia F, sob peso constante de 750g, a outro bloco idêntico de resina composta Clearfil AP-X (Kuraray). Os blocos de resina foram obtidos por meio de duplicação daqueles de cerâmica a partir de moldes com silicona de adição Express (3M). Os quatro conjuntos formados por cerâmica, cimento e resina foram seccionados em 20 corpos-de-prova com forma de palitos, de modo que a região adesiva apresentasse 1mm² de área. Dois grupos (n=10) foram constítuidos: G1- estocagem por 7 dias em água deionizada à 36 ± 2ºC; G2- 1500 ciclos entre 5ºC e 55ºC com intervalos de 30 segundos. A seguir, foi realizado o teste de microtração em máquina de ensaio universal (EMIC) com velocidade de 0,5 mm/min. Os resultados mostraram que os valores médios de tensão de ruptura (MPa) para o grupo G2: (22,815 ± 5,254) não tiveram diferenças estatisticamente significantes daqueles do grupo G1: (25,628 ± 3,353) (t= 1,427; gl = 18; p-valor = 0,171), ao nível de significância de 5%. A partir destes resultados, entendemos lícito concluir que o efeito da ciclagem térmica não produziu alterações estatisticamente significantes nos valores da resistência adesiva

Childhood trauma, midbrain activation and psychotic symptoms in borderline personality disorder

Childhood trauma is believed to contribute to the development of borderline personality disorder (BPD), however the mechanism by which childhood trauma increases risk for specific symptoms of the disorder is not well understood. Here, we explore the relationship between childhood trauma, brain activation in response to emotional stimuli and psychotic symptoms in BPD. Twenty individuals with a diagnosis of BPD and 16 healthy controls were recruited to undergo a functional MRI scan, during which they viewed images of faces expressing the emotion of fear. Participants also completed the childhood trauma questionnaire (CTQ) and a structured clinical interview. Between-group differences in brain activation to fearful faces were limited to decreased activation in the BPD group in the right cuneus. However, within the BPD group, there was a significant positive correlation between physical abuse scores on the CTQ and BOLD signal in the midbrain, pulvinar and medial frontal gyrus to fearful (versus neutral) faces. In addition there was a significant correlation between midbrain activation and reported psychotic symptoms in the BPD group (P<0.05). These results show that physical abuse in childhood is, in individuals with BPD, associated with significantly increased activation of a network of brain regions including the midbrain in response to emotional stimuli. Sustained differences in the response of the midbrain to emotional stimuli in individuals with BPD who suffered childhood physical abuse may underlie the vulnerability of these patients to developing psychotic symptoms

Desperdício de exames complementares na avaliação pré-operatória em cirurgias de catarata Waste of medical tests in preoperative evaluation for cataract surgery

O objetivo deste experimento clínico foi determinar a freqüência dos exames considerados dispensáveis numa rotina pré-operatória de facectomias e avaliar os gastos com eles. Se o paciente foi sorteado para testes-seletivos, solicitou-se que nenhum teste fosse executado, a menos que o paciente apresentasse um novo problema médico, ou piora de uma doença preexistente, a qual requeresse os testes independentemente da realização da cirurgia. Para pacientes sorteados para testes-rotineiros, foram solicitados: eletrocardiograma, dosagem de hemoglobina e glicemia de jejum. Foram calculados os gastos com exames considerados desnecessários. A amostra de 1.025 pacientes incluiu 513 sorteados para testes seletivos e 512 para testes rotineiros. A freqüência de eventos adversos intra-operatórios foi semelhante nos dois grupos (p = 0,923). O grupo de testes seletivos realizou de 60,7% menos exames que o de testes rotineiros. Os resultados sugerem que a requisição seletiva de exames pré-operatórios em facectomias, além de não prejudicar o paciente do ponto de vista de complicações clínicas intra-operatórias, possibilita expressiva economia de recursos quando comparada à atual rotina.<br>The objective of this clinical trial was to determine the frequency of medical tests considered unnecessary in routine preoperative evaluation for cataract surgery. Unnecessary costs with these tests were also evaluated. For patients assigned to the selective testing group, it was requested that no preoperative testing be performed unless the patient presented a new or worsening medical problem warranting medical evaluation with testing. For patients assigned to the routine testing group, three tests were requested: a 12-lead electrocardiogram, complete blood count, and serum glucose level. The costs of tests considered unnecessary were calculated. The sample of 1,025 patients consisted of 512 assigned to the routine testing group and 513 to the selective testing group. Cumulative rate of medical events was similar in the two groups (p = 0.923). The selective group underwent 60.7% fewer tests. The results suggest that selective preoperative testing in cataract surgery does not harm patients in terms of peri-operative clinical complications and also represents a significant cost reduction compared to routine testing