Far-Field Boundary Conditions for Calculation of Hole-Drilling Residual Stress Calibration Coefficients

The Hole-Drilling method for residual stress measurement, both in its standard version based on strain gauge rosettes (ASTM E837-08e1 2008) and its derivative using optical methods for estimating the displacement field around the hole (Baldi (2005) J Eng Mater Technol 127(2):165–169; Schajer and Steinzig (2005) Exp Mech 45(6):526–532; Schajer (2010) Exp Mech 50(2):159–168), relies on numerical calibrated coefficients (A and B) to correlate the experimentally acquired strains (displacements) with residual stress components. To estimate the A and B coefficients, two FEM (Finite Element Method) computations are required, the former related to a hydrostatic stress state, the latter to a pure shear case. Both can be implemented using either a semi-analytical approach (i.e. an axis-symmetric mesh expanded in the tangential direction using a Fourier series) or a tri-dimensional mesh, usually exploiting the double symmetry of the problem. Whatever the approach selected, the definition of constraints to be applied to the outer boundary is critical because the hole-drilling method assumes an infinite plate, thus both the usual solutions—fully constrained or free boundaries—are unable to correctly describe the theoretical situation. In the following, the problem of correct simulation of the infinite domain will be discussed and two simple and effective solutions will be proposed

Local detection of enzymatic ion generation with polycrystalline silicon interdigitated electrodes and its application to biosensing

Chips containing polycrystalline silicon interdigitated electrodes are modified with the enzyme urease. The sensors are able to detect changes in the resitivity of the solution near their surface, where the enzymatic reaction generates charged species. The electrodes are also grafted with an antigen and queried with different amounts of urease labeled antibody. The response of the modified electrodes is proportional to the amount of enzyme attached to the surface by the biorecognition event, thus validating the assay for biosensing applications

A comparison between APSK and QAM in wireless tactical scenarios for land mobile systems

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QuantiFERON-TB Gold Plus evaluation for latent tuberculosis infection among Italian healthcare workers: a cross-sectional study

Background: healthcare workers (HCWs) are at higher risk of being exposed to tuberculosis (TB). The aim of this study was to estimate LTBI prevalence and evaluate associated risk factors among Italian HCWs using a new generation IGRA test, Quantiferon Plus (QTF-Plus), providing also an analytical evaluation of this test. Methods: this cross-sectional study was conducted during the annual health surveillance program performed in 2017, evaluating 1470 HCWs of a teaching hospital in Rome, tested with QTF-Plus. A standardized questionnaire was collected for multivariate risk analysis. The independent variables associated with a higher frequency of LTBI were tested in a multivariate logistic regression model. Results: LTBI was diagnosed in 50 out of 1470 (3.4%) of HCWs. The male gender and age>40 years were significantly associated with the risk of LTBI. The levels of interferon-γ were significantly lower in subjects with a recent conversion than in those with an older positivity. Moreover, interferon-γ values exceeding 8 IU/ml were recorded in 8 out of 35 remote subjects but in no recent subjects. The concordance between TB1 and TB2 results was 88%, while in 6 out of 50 subjects we found a discrepancy. Conclusion: the LTBI condition among Italian HCWs was very low. In subjects with discordant outcomes between TB1 and TB2, especially when the test values are close to the cut-off, is recommended a repetition of the test to confirm its positivity. Key words: tuberculosis, latent tuberculosis infection, interferon-gamma release assay, quantiferon plus, healthcare worker

Human Infection with M- Strain of Brucella canis

The less mucoid strain of Brucella canis or M- strain is used for the serologic diagnosis of canine brucellosis. While this strain is avirulent in dogs, we report the case of clinical brucellosis that developed in a laboratory worker a few days after handling live M- cells for antigen production

Comparative Effectiveness of DPP-4 Inhibitors Versus Sulfonylurea for the Treatment of Type 2 Diabetes in Routine Clinical Practice: A Retrospective Multicenter Real-World Study

Introduction: DPP-4 inhibitors (DPP4i) and sulfonylureas are popular second-line therapies for type 2 diabetes (T2D), but there is a paucity of real-world studies comparing their effectiveness in routine clinical practice. Methods: This was a multicenter retrospective study on diabetes outpatient clinics comparing the effectiveness of DPP4i versus gliclazide extended release. The primary endpoint was change from baseline in HbA1c. Secondary endpoints were changes in fasting plasma glucose, body weight, and systolic blood pressure. Automated software extracted data from the same clinical electronic chart system at all centers. Propensity score matching (PSM) was used to generate comparable cohorts to perform outcome analysis. Results: We included data on 2410 patients starting DPP4i and 1590 patients starting gliclazide (mainly 30–60 mg/day). At baseline, the two groups differed in disease duration, body weight, blood pressure, HbA1c, fasting glucose, HDL cholesterol, triglycerides, liver enzymes, eGFR, prevalence of microangiopathy, and use of metformin. Among DPP4i molecules, no difference in glycemic effectiveness was detected. In matched cohorts (n = 1316/group), patients starting DPP4i, as compared with patients starting gliclazide, experienced greater reductions in HbA1c (− 0.6% versus − 0.4%; p < 0.001), fasting glucose (− 14.1 mg/dl versus − 8.8 mg/dl; p = 0.007), and body weight (− 0.4 kg versus − 0.1 kg; p = 0.006) after an average 6 months follow-up. DPP4i improved glucose control more than gliclazide, especially in patients who had failed with other glucose-lowering medications or were on basal insulin. Conclusions: This large retrospective real-world study shows that, in routine clinical practice, starting a DPP4i allows better glycemic control than starting low-dose gliclazide. Funding: The Italian Diabetes Society, with external support from AstraZeneca

Environmental impact assessment of three packages for high-quality extra-virgin olive oil

Life cycle assessments of food packaging technologies have shown that they contribute considerably to the environmental impact of products. This study analyses the life cycle impact of three packaging solutions for high-quality extra-virgin olive oil. Two of them are widely used solutions, namely tin plated cans and dimmed glass bottles. The third one is a stainless steel bottle, which has been proposed recently. The analysis was performed with a cradle to grave approach and it takes into account raw materials extraction and processing, packaging production processes and several end-of-life scenarios. Impacts due to distribution were considered separately to assess uncertainties due to distribution distances. The results show that, for same sizes, dimmed glass bottles have the lowest overall impact value for all the six indicators selected except for ozone layer depletion, whereas stainless steel bottles have the highest impact values for all the other indicators. A sensitivity analysis was performed to determine how impact varies in function of distance and packaging weight. It shows that it is possible to set a breakeven point over which the impact of glass overcomes the one of the other packaging systems. Packaging shows a significant contribution to impact of bottled oil. For small packaging, such as a 0.100 L stainless steel bottle, this contribution can be as relevant as 60% of the overall global warming potential

RTM process monitoring and strain acquisition by fibre optics

Abstract The development of Resin Transfer Moulding technology for advanced applications requires a detailed analysis and control of the process. Fibres optics and Fibres Bragg Gratings are useful tools to investigate composite structures during their lifetime service. They are here employed for the monitoring of manufacturing phase and the acquisition of strains during product usage in service. The adopted monitoring procedure allows to follow all the stages of the production process, evidencing their possible influences over final laminate characteristics. Resin injection, curing and cooling, mould extraction, sensor position, deformation control during mechanical testing are analysed on the basis of the signal output from fibre optic sensors embedded in a model component

EFFECTS OF OXIDISED LDL ON NITRIC OXIDE AND ENDOTHELIN-1 PRODUCTION IN HUMAN MICROVASCULAR ENDOTHELIUM: ROLE OF THROMBOXANE A2 RECEPTOR

LDL particles modulate the release of NO and endothelin-1 by the endothelium. To what extent these effects depend on LDL concentration and degree of oxidation and eventually what is the role of tromboxane A2 receptor is unknown. HMEC-1 were exposed for 24-h to a) 3 concentrations (50, 100 and 200 ?g/ml) of either native, low- or medium-oxidised LDL, b) 8-epi-PGF2? (F2?IP, 10-11, 10-10, 10-9, and 10-8 M) either alone or with TXA2 receptor blocker SQ 29.548 (10-6 M), c) native, low- and medium-oxidised LDL either alone or with SQ 29.548 (10-6 M). In all experiments intracellular eNOS, and NO2/NO3, endothelin-1 and interleukin-6 concentration in the medium were measured. Both native and oxidised LDL induced a NO2/NO3 accumulation with dose and degree of oxidation acting synergistically; eNOS was stimulated only by oxidised LDL. F2?IP, NO2/NO3 and eNOS with SQ 29.548 completely preventing these effects but only partially the effect of LDL. IL-6 was also synergistically stimulated by LDL dose and degree of oxidation but not by direct exposure to F2?IP nor was affected by SQ 29.548. Both native and oxidised LDL stimulated endothelin-1 production independently of dose or degree of oxidation. F2?IP had a modest stimulatory effect while the effect of SQ 29.548 was evident only with oxidised LDL. In HMEC-1 LDL dose and degree of oxidation synergistically stimulate NO and IL-6 production and the effect on NO is largely mediated through the TXA2 receptor. LDL simultaneously facilitate endothelin-1 production independently of the dose and degree of oxidation