Ultimate strength of adjustable telescopic steel props according to standard EN 1065

The European standard EN 1065 - to which most current European production appears not to have been upgraded - addresses the design and the manufacturing of adjustable telescopic steel props, an interest bearing economic sector. The present work aims at showing an efficient strategy for the assessment of the ultimate strength of steel props according to EN 1065 in order to identify the ideal cost-performance ratio in the real life production

Experimental Results on Staggered Lapped Bars in FRC

The paper presents experimental results on lap splices in fiber reinforced concrete (FRC). Four point bending tests were carried out on several full-scale beams with all or part of the longitudinal reinforcement lap spliced at mid-span. The beams were reinforced with either 16 mm or 20 mm diameter rebars and included various lap splices configurations varying the percentage of lapped bars. The behaviour of lapped bars in FRC with a volume content of steel hooked fibres equal to 0.5% was investigated. The results show that the post-peak behaviour of FRC can enhance the strength of staggered lapped splices as well as it can reduce their brittleness, thus allowing a reduction of lap length when only a portion of bars at a section are lapped. The results show also the benefits on the durability of concrete members due to the capability of the fibres to markedly reduce the splitting cracks along the splice at service loadings

Design and assessment of adjustable telescopic props with innovative shape

The design of optimal props (in terms of weight) that conform to the European standard EN 1065 is not a straightforward task. For some classes of props, when the collapse mechanism is the failure of the prop base, large tubes thicknesses or large tubes diameters are required to keep the failure mechanism under control, although the substantial strength of the tubes remains unexploited. This observation motivates the seek for innovative shapes. The present work aims at showing a new proposal of efficient design of props in agreement with the standard EN 1065. Theoretical and numerical analysis are carried out in order to identify the effective gain of weight of this new design configuration

In vitro replication capacity of HIV-2 variants from long-term aviremic individuals

AbstractTo establish whether efficient suppression of virus replication in HIV-2-infected individuals is associated with low replicative capacity of HIV-2, replication kinetics of HIV-2 variants from long-term aviremic individuals was analyzed and compared with that of the relatively slow-replicating HIV-1 variants from asymptomatics and long-term nonprogressors (AS/LTNP). On average, HIV-2 from aviremic individuals had lower replication rates than HIV-1 variants from AS/LTNP in cells of 8 donors (0.45 log10 [range 0.14–0.77] vs. 0.58 log10 [range 0.32–0.99] pg RT/ml/day, P = 0.036). The relatively low replication rate of HIV-2 compared to HIV-1 variants was not related to different sensitivities to inhibition by CD8+ T cells or different degrees of infectivity. HIV-2 replication rates increased with progressive infection and with switch from CCR5 to CXCR4 usage.The relatively low replicative capacity of HIV-2 variants from aviremic individuals likely contributes to the low viral load and benign course of infection in these individuals

Lynch Syndrome from a surgeon perspective: retrospective study of clinical impact of mismatch repair protein expression analysis in colorectal cancer patients less than 50 years old.

BACKGROUND: In clinical practice, unexpected diagnosis of colorectal cancer in young patients requires prompt surgery, thus genetic testing for Lynch Syndrome is frequently missed, and clinical management may result incorrect. METHODS: Patients younger than 50 years old undergoing colorectal resection for cancer in the period 1994-2007 were identified (Group A, 49 cases), and compared to a group of randomly selected patients more than 50 (Group B, 85 cases). In 31 group A patients, immunohistochemical expression analysis of MLH1, MSH2 and MSH6 was performed; personal and familial history of patients with defective MMR proteins expression was further investigated, searching for synchronous and metachronous tumors in probands and their families. RESULTS: Fifty-one percent of patients did not express one or more MMR proteins (MMR-) and should be considered Lynch Syndrome carriers (16 patients, group A1); while only 31.2% of them were positive for Amsterdam criteria, 50% had almost another tumor, 37.5% had another colorectal tumor and 68% had relatives with colorectal tumor. This group of patients, compared with A2 group (< 50 years old, MMR+) and B group, showed typical characteristics of HNPCC, such as proximal location, mucinous histotype, poor differentiation, high stage and shorter survival. CONCLUSIONS: The present study confirms that preoperative knowledge of MMR proteins expression in colorectal cancer patients would allow correct staging, more extended colonic resection, specific follow-up and familial screening

Immune reconstitution inflammatory syndrome in HIV infected late presenters starting integrase inhibitor containing antiretroviral therapy

Background: Integrase inhibitors (INI) induce a rapid decline of HIV-RNA in plasma and CD4+ T-cell recovery in blood. Both characteristics are also associated with immune reconstitution inflammatory syndrome (IRIS). Whether the use of INI-containing combination antiretroviral therapy (cART) increases the risk of IRIS is being questioned. Methods: Study within the Dutch ATHENA HIV observational cohort. HIV-1 infected late presenters initiating cART after March 2009 were included if they had <200 CD4+ T-cells per μL and were diagnosed with an opportunistic infection. IRIS was defined either according to the criteria by French et al. (IRISFRENCH) or by a clinical IRIS diagnosis of the physician (IRISCLINICAL). The primary outcomes were the association between INI and the occurrence of IRISFRENCH and IRISFRENCH+CLINICAL in multivariable logistic regression. Findings: 672 patients with a median CD4+ T-cell count of 35 cells per μL were included. Treatment with INI was independently associated with IRISFRENCH as well as IRISFRENCH+CLINICAL (OR 2·43, 95%CI:1·45-4·07, and OR 2·17, 95%CI:1·45-3·25). When investigating INI separately, raltegravir (RAL) remained significantly associated with IRISFRENCH (OR 4·04 (95%CI:1·99-8·19) as well as IRISFRENCH+CLINICAL (OR 3·07, 95%CI:1·66-5·69), while dolutegravir (DTG) became associated with IRISFRENCH+CLINICAL after it replaced RAL as preferred INI in the cohort after 2015 (OR 4·08, 95%CI:0·99-16·82, p=0·052). Too few patients used elvitegravir to draw meaningful conclusions. Steroid initiation for IRIS was more likely in those who initiated INI versus in those who did not, but no increased hospital (re)admission or mortality rates were observed. Interpretation: In HIV late presenters from a resource rich setting, INI based treatment initiation increased the risk of IRIS. This was observed for RAL and DTG when being initiated as preferential INI in the presence of specific AIDS-conditions, indicative of channeling bias. Although we controlled for all relevant measured confounders, we cannot exclude that the observed association is partially explained by residual confounding. INI use was not associated with mortality nor hospitalization. Therefore, our observation is no reason to avoid INI in late presenters. Funding: The ATHENA database is maintained by Stichting HIV Monitoring and supported by a grant from the Dutch Ministry of Health, Welfare and Sport through the Centre for Infectious Disease Control of the National Institute for Public Health and the Environment

Risk of intracranial haemorrhage and ischaemic stroke after convexity subarachnoid haemorrhage in cerebral amyloid angiopathy: international individual patient data pooled analysis

OBJECTIVE: To investigate the frequency, time-course and predictors of intracerebral haemorrhage (ICH), recurrent convexity subarachnoid haemorrhage (cSAH), and ischemic stroke after cSAH associated with cerebral amyloid angiopathy (CAA). METHODS: We performed a systematic review and international individual patient-data pooled analysis in patients with cSAH associated with probable or possible CAA diagnosed on baseline MRI using the modified Boston criteria. We used Cox proportional hazards models with a frailty term to account for between-cohort differences. RESULTS: We included 190 patients (mean age 74.5 years; 45.3% female) from 13 centers with 385 patient-years of follow-up (median 1.4 years). The risks of each outcome (per patient-year) were: ICH 13.2% (95% CI 9.9-17.4); recurrent cSAH 11.1% (95% CI 7.9-15.2); combined ICH, cSAH, or both 21.4% (95% CI 16.7-26.9), ischemic stroke 5.1% (95% CI 3.1-8) and death 8.3% (95% CI 5.6-11.8). In multivariable models, there is evidence that patients with probable CAA (compared to possible CAA) had a higher risk of ICH (HR 8.45, 95% CI 1.13-75.5, p = 0.02) and cSAH (HR 3.66, 95% CI 0.84-15.9, p = 0.08) but not ischemic stroke (HR 0.56, 95% CI 0.17-1.82, p = 0.33) or mortality (HR 0.54, 95% CI 0.16-1.78, p = 0.31). CONCLUSIONS: Patients with cSAH associated with probable or possible CAA have high risk of future ICH and recurrent cSAH. Convexity SAH associated with probable (vs possible) CAA is associated with increased risk of ICH, and cSAH but not ischemic stroke. Our data provide precise risk estimates for key vascular events after cSAH associated with CAA which can inform management decisions