Finite element computation of void growth damage in thermo-viscoplasticity

A thermo-viscoplastic damage model based on a visco-plastic potential leads to an expression for a consistent tangent operator for finite element discretization. Implicit schemes are used for strain, void volume fraction and temperature computations which are then available to describe the essential damage evolutions due to microvoids growth in most polycrystalline and ductile materials. A typical numerical test is given for a four node quadrilateral element and a full computation example involves the finite element tensile test model of a standard notched cylindrical specimen.     

Stroke in pregnancy and the puerperium

Recent studies suggest that the risk of cerebral infarction is increased during the puerperium but not during pregnancy itself. Most of the known causes of ischaemic stroke in the young have been reported during pregnancy. In most of these conditions, it is uncertain whether pregnancy is coincidental or plays a role in the occurrence of stroke. Eclampsia is the main pregnancy-specific cause, which may be associated with focal neurological deficits of sudden onset, consistent with a clinical diagnosis of stroke. However, the precise pathogenesis of these stroke-like focal deficits remains poorly understood. The two other pregnancy-specific conditions (choriocarcinoma and amniotic fluid embolism) are rarely responsible for focal cerebral ischaemia. In a significant number of patients, the cause of the stroke remains undetermined, despite an extensive aetiological investigation. Whether a hypercoagulable state and vessel wall changes associated with pregnancy may play a role in the occurrence of these otherwise unexplained ischaemic strokes remains unknown. The occurrence of cerebral venous thrombosis is clearly linked to the puerperal state, suggesting a direct role of the latter. However, cerebral venous thrombosis during pregnancy or the puerperium has been related to various aetiologies, stressing the need for an aetiological study, particularly when the thrombosis occurs during pregnancy. Pregnancy may increase the risk of subarachnoid haemorrhage, The most common cause is rupture of an arterial aneurysm. Although this is a controversial issue, the increased tendency of an aneurysm to bleed with advancing gestational age suggests that haemodynamic, hormonal or other physiological changes of pregnancy may play a role in aneurysmal rupture. The classic notion that rupture of an arterial aneurysm occurs more frequently during labour has not been confirmed. Most authors agree that surgical management after subarachnoid haemorrhage in pregnancy should be the same as that in the non-pregnant state. Data specifically devoted to intraparenchymal haemorrhage in pregnancy are scarce. Pregnancy and in particular the puerperium seem to be associated with an increased risk of intracerebral haemorrhage. The most common causes are eclampsia and ruptured vascular malformations. Whether pregnancy increases the risk of rupture of an arteriovenous malformation is controversial.     

Comparison of autologous bone marrow transplantation and intensive chemotherapy as postremission therapy in adult acute myeloid leukemia. The Groupe Ouest Est Leucémies Aigu?s Myéloblastiques (GOELAM)

Three intensive consolidation strategies are currently proposed to younger adults with acute myeloid leukemia (AML) in first complete remission (CR): allogeneic or autologous bone marrow transplantation (BMT) and intensive consolidation chemotherapy (ICC). Patients aged 15 to 50 years with de novo AML received an induction treatment with 7 days of cytarabine and either idarubicin or rubidazone. After achievement of a CR, patients up to the age of 40 and having an HLA-identical sibling were assigned to undergo an allogeneic BMT. All the other patients received a first course of ICC with high-dose cytarabine and the same anthracycline as for induction. They were then randomly assigned to either receive a second course of ICC with amsacrine and etoposide or a combination of busulfan and cyclosphosphamide followed by an unpurged autologous BMT. Of 517 eligible patients, 367 had a CR, but only 219 (59.5%) actually received the planned intensive postremission treatment (73 allogeneic BMT, 75 autologous BMT, and 71 ICC). With a median follow-up of 62 months, the 4-year disease-free survival (DFS) of the 367 patients in CR was 39.5%. The 4-year overall survival (OS) of the 517 eligible patients was 40.5%. In multivariate analysis, DFS and OS were influenced only by the initial white blood cell count and by the French-American-British classification. The type of postremission therapy had no significant impact on the outcome. There was no difference in the 4-year DFS and OS between 88 patients for whom an allogeneic BMT was scheduled (respectively, 44% and 53%) and 134 patients of the same age category and without an HLA-identical sibling (respectively, 38% and 53%). Similarly, there was no difference in the outcome between autologous BMT and ICC. The 4-year DFS was 44% for the 86 patients randomly assigned to autologous BMT and 40% for the 78 patients assigned to ICC (P = .41). The 4-year OS was similar in the two groups (50% v 54.5%, P = .72). The median duration of hospitalization and thrombocytopenia were longer after autologous BMT (39 v 32 days, P = .006, and 109.5 v 18.5 days, P = .0001, respectively). After a first course of ICC, a second course of chemotherapy is less myelotoxic than an unpurged autologous BMT but yields comparable DFS and OS rates.     

Nephrotic syndrome. What is new since the 1988 study?

Hormone-refractory prostate cancer (HRPC) patients often have nonmeasurable disease. In such patients, predictive biomarkers other than tumor response may be required to compare therapeutic effects. We examined the predictive value for survival of various clinical and laboratory parameters, including prostate-specific antigen (PSA), in HRPC patients treated with suramin. Data from 103 HRPC patients were analyzed using various survival analyses, the likelihood ratio approach, and logistic regression analyses. When pretreatment factors, percentage decrease in PSA at 4 weeks from start of treatment (deltaPSA), and updated survival data were fit by a multivariate Cox proportional hazards model, acid phosphatase, lactate dehydrogenase, and deltaPSA were significant, with risk ratios close to 1. There was a decrease in likelihood ratio with increasing APSA. A logistic regression model was developed to predict the probability of <1 year of survival from the start of treatment. Hemoglobin and deltaPSA were found to be significant variables. However, in view of the complexities involving the relationship between PSA expression and prostate cancer growth and possible selective effect of treatment on PSA, further prospective testing is necessary. Therefore, deltaPSA cannot necessarily be used as a biomarker for survival response in individual patients during the evaluation of the therapeutic response of HRPC to new antineoplastic drugs.     

Emotional priming of pop-out in visual search.

When searching for a discrepant target along a simple dimension such as color or shape, repetition of the target feature substantially speeds search, an effect known as feature priming of pop-out (V. Maljkovic and K. Nakayama, 1994). The authors present the first report of emotional priming of pop-out. Participants had to detect the face displaying a discrepant expression of emotion in an array of four face photographs. On each trial, the target when present was either a neutral face among emotional faces (angry in Experiment 1 or happy in Experiment 2), or an emotional face among neutral faces. Target detection was faster when the target displayed the same emotion on successive trials. This effect occurred for angry and for happy faces, not for neutral faces. It was completely abolished when faces were inverted instead of upright, suggesting that emotional categories rather than physical feature properties drive emotional priming of pop-out. The implications of the present findings for theoretical accounts of intertrial priming and for the face-in-the-crowd phenomenon are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sepsis and serum cytokine concentrations

Hematological and plasma chemistry parameters were measured in 129 juvenile white storks (Ciconia ciconia), either wild or captive bred, April to June 1994. Wild storks were members of a colony in the Lozoya River Valley, Madrid, Spain. Red blood cells count, packed cell volume and hemoglobin increased significantly with age. White blood cells count, lymphocytes count and platelets decreased with age. Total solids, total proteins, fibrinogen, albumin, alpha, beta, gamma-globulins and urea increased with age. Differences between captive and wild birds were not notable.     

Three-dimensional reconstruction of the alpha D and beta C-hemocyanins of Helix pomatia from frozen-hydrated specimens

The three-dimensional (3D) reconstructions of the di-decameric forms of alpha D and beta C-hemocyanins of the Roman snail Helix pomatia and of the decameric half molecules of alpha D-hemocyanin were carried out on frozen-hydrated specimens observed in the electron microscope by using the random conical tilt series method. The three 3D volumes were examined by computing solid-body surface representations and slices through the volume and by eroding the structure progressively through raising of the threshold. The di-decameric molecule of alpha D and beta C-hemocyanins, reconstructed from side views, are very similar and are composed of a cylindrical wall, comprising ten oblique wall units, and of two collar complexes located at both ends of the cylinder, comprising each five arches and an annular collar made up of five collar units. Erosion of the structure reveals that the wall looks like a segment of a five-stranded right-handed helix and that each oblique wall unit resembles a figure 8 inclined to the right. The decameric half molecule of alpha D-hemocyanin, reconstructed from end-on views, resembles the whole molecule, except that the collar is thinner and appears composed of five independent collar complex units. It is suggested that the difference in structural appearance of the collar complex between the whole and the half alpha D-hemocyanin may be due to the missing cone artifact, induced by the angular limitations imposed by the goniometer of the electron microscope. The comparison between the alpha D-hemocyanin and the beta C-di-decameric hemocyanin at high thresholds suggests that in the beta C-hemocyanin the oblique wall units of each half molecule may be linked by two connections, whereas in alpha D-hemocyanin there may be only one. This difference in the number of connections may be responsible for the lower stability of the alpha D molecule at high salt concentration.     

Oxydation electrocatalitique du glycerol sur electrodes d'or et de platine en milieu aqueux

The electrocatalytic oxidation of glycerol has been investigated at platinum and gold electrodes, both in acid and in alkaline medium. In acid medium only platinum electrodes are electroactive, whereas in alkaline medium both electrodes, particularly gold electrodes, give relatively high current densities (about 20 mA cm^?2 for 0.1 M glycerol at 25°C).By varying the reaction parameters (electrode potential, concentrations of glycerol and of hydroxylions), it is possible to determine the transfer coefficient and the reaction orders. The fractional values obtained may be interpreted by formulating a reaction mechanism involving adsorbed intermediates.