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AN INTERNAL DOCUMENT recovered by the Associated Press in Timbuktu in January 2013 sheds new light on al-Qa'ida in the Islamic Maghreb's (AQIM) strategy in northern Mali. (1) The document [...]

In this study, the critical state friction angle in a direct shear box was tested at vertical effective stresses between 4 kPa and 150 kPa for seven sands of different origins. The results show a stress dependency on the angle of friction at low vertical stresses, and that the critical state friction angle decreases with increase in the vertical effective stress. The largest drop occurs for vertical effective stresses between 4 kPa and 50 kPa and varies between 4° and 10° depending mostly on the shape of the sand particles and the difference in the extreme void ratios.

To The Washington Post, June 24, 2011 Last week, Morocco's King Mohammed VI announced major constitutional reforms, which could have serious implications for U.S. foreign policy. Amid the 'Arab Spring,' [...]

The angle of repose—the maximum angle that allows a heap of soil to remain stable without failing—is an important property of soils and affects the safety and costs of projects such as slopes or retaining walls. But several methods have been proposed to measure it, which might produce confusion in practice and research. The angles of repose obtained using six different methods for six different sands are compared here in order to quantify and explain the differences and determine some of the factors that influence the angle’s value. The results show that the highest values are obtained with the ASTM International and Cornforth methods, followed by scoop deposition (6 % smaller), the Santamarina and Cho dry method (12 % smaller), and the cone lifting method (35 % smaller). Both the cone lifting method and the Santamarina and Cho wet method produce segregation of the finer particles for sands having a specific gravity greater than 2.7 and a difference of extreme void ratios larger than 0.3.

AbstractAnalyses of severe accidents in nuclear power plants by using integral codes are necessary in order to develop accident management strategies that prevent such accidents or mitigate their consequences for the environment. The most important requirement for the development of integral codes is to achieve good predictability of a given accident scenario through the understanding and quantification of severe accident phenomena and their underlying physical and chemical processes. In this paper, the progress in modeling the processes related to the radioactive source term, and in particular progress related to the release and transport of fission products in the circuit and containment, is demonstrated by the assessment of integral and detailed codes using the experimental results of the in-pile Phebus fission product tests (FPTs). It is shown that the integral codes are good in predicting both the hydrogen release and the total release of volatile fission products from the bundle.It is also shown that the commonly used fission product transport codes overestimate the deposited aerosol mass in the Phebus steam generator. However, by using an improved model for the thermophoretic aerosol particle deposition, it has been possible to reproduce the aerosol mass deposited in the steam generator more accurately. The containment analyses carried out with both lumped-parameter and multidimensional computational fluid dynamics codes showed that the measured thermal-hydraulic data are accurately reproduced. The aerosol behavior in the containment estimated from the lumped-parameter codes corresponded satisfactorily to the experimental data. The iodine chemistry codes highlighted the substantial role of silver released from the degraded absorber rod (Ag-In-Cd), as it was observed experimentally; however, the temporal dependence of the gaseous iodine concentration in the containment atmosphere was poorly calculated. There are plans to improve the modeling in order to reproduce better the fission product release from the bundle, the fission product transport in the primary circuit duct, and the gas phase chemistry in the containment, with particular emphasis on gaseous iodine species. Further plans include the analysis of Phebus FPT3, which was the last in the series of Phebus tests, with its boron-carbide control rod.

Background This study investigated prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients.Methods A cross-sectional analysis was performed on registry data for 2,746 chronic (<6 months) hemodialysis patients aged 25–84. Data collection included years of dialysis, hours of dialysis/wk, disease causing hemodialysis, body mass index (BMI), erythropoietin (EPO) treatment, hemoglobin, markers of viral hepatitis, serum albumin, calcium, and phosphorus.Results Prevalence was 88.7% for anemia (hemoglobin <11 g/100 mL and EPO treatment at any Hb level), 39.4% for uncontrolled anemia (hemoglobin<11 g/100 mL). Gender, years of dialysis, hereditary cystic kidney disease (HCKD), and low BMI (<24 kg/m2) were independent correlates of anemia (P<0.001). Gender, HCKD, low BMI, serum albumin and calcium were independent correlates of uncontrolled anemia (P<0.05). An interaction was found between age (not correlated with anemia and uncontrolled anemia) and the association of gender with uncontrolled anemia (P<0.05). EPO doses were higher in patients with high prevalence of uncontrolled anemia than in patients with low prevalence (i.e., women vs men, other diseases vs HCKD, low vs not-low BMI, P<0.01). Gender, years of dialysis, HCKD, BMI, serum albumin, and calcium were independent correlates of the hemoglobin/EPO dose ratio in patients on EPO treatment (P<0.05).Conclusion Anemia and uncontrolled anemia are more frequent in hemodialysis patients with short-term dialysis, diseases other than HCKD, low BMI, and female gender. Gender effect was lower in elderly patients. Uncontrolled anemia was also associated with low serum albumin and calcium, suggesting that these parameters are indices of EPO resistance.

The serine/threonine kinase protein kinase B (PKB/c-Akt) acts downstream of the lipid kinase phosphoinositide 3-kinase (PI3K) and functions as an essential mediator in many growth-factor-induced cellular responses such as cell cycle regulation, cell survival and transcriptional regulation. PI3K activation generates 3′-phosphorylated phosphatidylinositol lipids(PtdIns3P) and PKB activation requires PtdIns3P-dependent membrane translocation and phosphorylation by upstream kinases. However PKB activation and function is also regulated by interaction with other proteins. Here we show binding of PKB to periplakin, a member of the plakin family of cytolinker proteins. Interaction between PKB and periplakin was mapped to part of the pleckstrin homology (PH) domain of PKB, which is probably not involved in lipid binding, and indeed binding to periplakin did not affect PKB activation. We therefore investigated the possibility that periplakin may act as a scaffold or localization signal for PKB. In cells endogenous periplakin localizes to different cellular compartments, including plasma membrane,intermediate filament structures, the nucleus and mitochondria. Overexpression of the C-terminal part of periplakin, encompassing the PKB binding region,results in predominant intermediate filament localization and little nuclear staining. This also resulted in inhibition of nuclear PKB signalling as indicated by inhibition of PKB-dependent Forkhead transcription factor regulation. These results suggest a possible role for periplakin as a localization signal in PKB-mediated signalling.

Induction of apoptosis by Fas ligand (FasL) of Fas‐containing cells is a known mechanism involved in the eradication of inappropriate cells during normal development. Alterations of the Fas/FasL pathway have been found in various types of cancer, leading to circumvention of attack of the tumour by the immune system. An alternative way to circumvent eradication by induction of apoptosis is through changes in the downstream inhibitors. For example, Fas‐associating phosphatase‐1 (Fap‐1) binds directly to the Fas receptor and results in a block of the downstream signalling. To shed more light on the role of the Fas/FasL pathway in the development of human testicular germ cell tumours of the adult testis, this study investigated the presence of Fas, FasL, Fap‐1, HLA class I and II molecules, CD45 (lymphocyte marker), and CD57 [natural killer (NK) cell marker] by immunohistochemistry on frozen sections of 41 cases of seminomas, non‐seminomas, and spermatocytic seminomas. Every germ cell tumour was positive for Fap‐1 and negative for HLA classes I and II, like their non‐malignant cells of origin. The infiltrating lymphocytes, predominantly present in seminomas, showed consistently positive staining for Fas and CD45, but not for Fap‐1. No Fas was found on NK cells. All seminomas and non‐seminomas (except teratomas), including their precursor stages, carcinoma in situ, intratubular seminoma and intratubular non‐seminoma, showed positive staining for FasL, but not for Fas. Teratoma showed no staining for FasL and was positive for Fas. In contrast, both Fas and FasL were detectable on spermatocytic seminoma. These data indicate a different regulation of the Fas/FasL system in seminoma and spermatocytic seminoma, supporting a separate pathogenesis for these germ cell‐derived tumours. The presence of Fap‐1 in all histological variants of germ cell tumours might be related to the consistently positive staining in cells of the germ lineage. This study indicates that production of FasL by the germ cell tumour cells might be involved in the early development of these types of adult testicular cancer by inducting apoptosis of Fas‐positive, Fap‐1‐negative tumour‐infiltrating lymphocytes. Copyright © 2002 John Wiley & Sons, Ltd.

Abstract: Background. Prenatal diagnosis of fetal brain anomalies relies mainly upon ultrasonography. However, even in the most experienced hands, the technique has limitations for some difficult diagnoses. MRI is an excellent imaging modality for the paediatric and adult brain. Objective. To assess the value of prenatal MRI when a cerebral anomaly was detected by US and where the prognosis depended on the identification of other anomalies undetectable by US, or where fetuses were at risk for a CNS lesion even when the US was normal. Materials and methods. Four hundred prenatal MRI examinations were performed since 1988, and confirmed by postnatal follow-up or pathological examination. Two-thirds of the examinations were performed after 25 weeks of gestation, one-third between 21 and 26 weeks. Fetal immobilisation was obtained by maternal premedication with flunitrazepam, administered orally 1 h before the examination. The examinations were performed on 1.5 T scanners using one or two surface coils. Results. Prenatal MRI allowed the diagnosis of serious unsuspected lesions such as neuronal migration disorders, ischaemic and haemorrhagic lesions and the abnormalities observed in tuberous sclerosis. It helped to characterise ventricular dilatation and anomalies of the corpus callosum and of the posterior fossa. Conclusions. MRI is a valuable complementary tool when prenatal US is incomplete, doubtful or limited. Prenatal MRI is particularly useful for the detection of ischaemic and haemorrhagic lesions, neuronal migration disorders and tuberous sclerosis lesions. Detection of these associated anomalies worsens the fetal prognosis, has medico-legal implications and modifies obstetric management. Normal prenatal MRI does not exclude an anomaly.

This study helps establish how electronic performance monitoring may influence employee physical strain levels through job design. It identifies job design variables which differ between monitored and non-monitored employees in the telecommunications industry (using discriminant function analysis). These variables' relationships to psychological stress outcomes were examined using multiple regression analysis. A group of 704 employees in three job categories (telephone operator {n=228}, customer service representative {n=230}, and clerk {n=246}) responded to a questionnaire survey mailed to their residence. Four hundred thirty-four of the respondents were monitored and 264 were not. The results indicated that the monitored employees had significantly higher levels of reported psychological stress than the non-monitored employees. The discriminant function analysis of job design variables showed that a variety of job design factors discriminated between monitored and non-monitored employees. High levels of workload, few lulls between periods of high workload, high levels of career/future ambiguity, poor relationships with supervisors, as well as low levels of task meaningfulness and completeness were significant predictors of psychological stress outcomes (tension, anxiety, depression and fatigue).

The purpose of this study was to examine worker perceptions of the work environment and psychological strain across job categories, as well as relationships between perceptions of the work environment and strain among office workers. Two-hundred-sixty-two employees from three public service organizations participated in the study. Using a questionnaire, we obtained measures of the work environment and of psychological strain. Office jobs were classified in seven job categories. Discriminant analyses showed that worker perceptions of the work environment varied across job categories, while the variation in strain was minimal. Worker perceptions of the work environment were related to some of the indicators of psychological strain. The most consistent predictor of strain was job control.

Activation of phosphatidylinositide 3′-OH kinase (PI 3-kinase) is implicated in mediating a variety of growth factor-induced responses, among which are the inactivation of glycogen synthase kinase-3 (GSK-3) and the activation of the serine/threonine protein kinase B (PKB). GSK-3 inactivation occurs through phosphorylation of Ser-9, and several kinases, such as protein kinase C, mitogen-activated protein kinase-activated protein kinase-1 (p90Rsk), p70S6kinase, and also PKB have been shown to phosphorylate this site in vitro. In the light of the many candidates to mediate insulin-induced GSK-3 inactivation we have investigated the role of PKB by constructing a PKB mutant that exhibits dominant-negative function (inhibition of growth factor-induced activation of PKB at expression levels similar to wild-type PKB), as currently no such mutant has been reported. We observed that the PKB mutant (PKB-CAAX) acts as an efficient inhibitor of PKB activation and also of insulin-induced GSK-3 regulation. Furthermore, it is shown that PKB and GSK-3 co-immunoprecipitate, indicating a direct interaction between GSK-3 and PKB. An additional functional consequence of this interaction is implicated by the observation that the oncogenic form of PKB, gagPKB induces a cellular relocalization of GSK-3 from the cytosolic to the membrane fraction. Our results demonstrate that PKB activation is both necessary and sufficient for insulin-induced GSK-3 inactivation and establish a linear pathway from insulin receptor to GSK-3. Regulation of GSK-3 by PKB is likely through direct interaction, as both proteins co-immunoprecipitate. This interaction also resulted in a translocation of GSK-3 to the membrane in cells expressing transforming gagPKB.

The possibility of utilizing urea nitrogen for synthesis of nonessential amino acids in patients with chronic uremia on diets rich in essential amino acids was set forth in an earlier investigation. To test this hypothesis 15N urea was given to a normal subject and to a group of four patients with chronic renal failure.The recovery of the isotope was attempted in all the component amino acids of plasma albumin and was found to be maximal in glutamic acid, alanine, aspartic acid, and serine but negligible in histidine, phenylalanine, methionine, threonine and tryptophan. On a low protein diet renal patients utilized urea two to three times more than the normal control. On an essential amino acid diet the utilization of urea was even more pronounced. Suppression of intestinal flora with Humatin greatly reduced urea utilization. The data provide support for the recommendation for treating patients with chronic uremia with diets low in nitrogen but rich in essential amino acids.