An analysis on the factors associated with reuse of insulin pen needles in type 2 diabetic patients in China

Incorrect injection technique of insulin is a common problem worldwide, which can reduce the efficacy of insulin therapy and lead to poor glucose control. A cross-sectional, multiple-center survey from 44 hospitals was conducted from Nov. 2015 to Dec. 2015. Non-parametric Kruskal–Wallis analysis of variance and Mann-Whitney U test were used for multi-parametric analysis. Multivariable logistic regressions were performed to identify the factors associated with independent variables. Overall, a single needle was used at an average of 3.79 times, with the highest of 60 times. Analysis across all study participants showed that the frequency of a single needle was positively correlated with age (P = 0.029), duration of diabetes (P≤0.001) and number of complications (P≤0.001). Multivariable logistic regressions analysis of insulin pen needle reuse and needle compliance showed that age, income, education, marital status, duration of diabetes, quality of life and cost of drug were significantly related to needle reuse. From this survey, we found that reuse of insulin pen needle was common in China. Frequency of needle reuse was related to the patients’ demographic characteristics (income level, age, region, education, employment status and self-care), health-related variables (duration of diabetes, number of complications and EQ-5D index scores) and utilization of health services (clinical visits, hospitalization and cost of medications).     

Large-scale decontamination of disposable FFP2 and FFP3 respirators by hydrogen peroxide vapour,Finland, April to June 2020

BackgroundThe shortage of FFP2 and FFP3 respirators posed a serious threat to the operation of the healthcare system at the onset of the COVID-19 pandemic.AimOur aim was to develop and validate a large-scale facility that uses hydrogen peroxide vapour for the decontamination of used respirators.MethodsA multidisciplinary and multisectoral ad hoc group of experts representing various organisations was assembled to implement the collection and transport of used FFP2 and FFP3 respirators from hospitals covering 86% of the Finnish population. A large-scale decontamination facility using hydrogen peroxide vapour was designed and constructed. Microbiological tests were used to confirm efficacy of hydrogen peroxide vapour decontamination together with a test to assess the effect of decontamination on the filtering efficacy and fit of respirators. Bacterial and fungal growth in stored respirators was determined by standard methods.ResultsLarge-scale hydrogen peroxide vapour decontamination of a range of FFP2 and FFP3 respirator models effectively reduced the recovery of biological indicators: Geobacillus stearothermophilus and Bacillus atrophaeus spores, as well as model virus bacteriophage MS2. The filtering efficacy and facial fit after hydrogen peroxide vapour decontamination were not affected by the process. Microbial growth in the hydrogen peroxide vapour-treated respirators indicated appropriate microbial cleanliness.ConclusionsLarge-scale hydrogen peroxide vapour decontamination was validated. After effective decontamination, no significant changes in the key properties of the respirators were detected. European Union regulations should incorporate a facilitated pathway to allow reuse of appropriately decontaminated respirators in a severe pandemic when unused respirators are not available.     

Influence of the AlSi7Mg0.6 Aluminium Alloy Powder Reuse on the Quality and Mechanical Properties of LPBF Samples

Additive manufacturing (AM) is dynamically developing and finding applications in different industries. The quality of input material is a part of the process and of the final product quality. That is why understanding the influence of powder reuse on the properties of bulk specimens is crucial for ensuring the repeatable AM process chain. The presented study investigated the possibility of continuous reuse of AlSi7Mg0.6 powder in the laser powder bed fusion process (LPBF). To date, there is no study of AlSi7Mg0.6 powder reuse in the LPBF process to be found in the literature. This study aims to respond to this gap. The five batches of AlSi7Mg0.6 powder and five bulk LPBF samples series were characterised using different techniques. The following characteristics of powders were analysed: the powder size distribution (PSD), the morphology (scanning electron microscopy—SEM), the flowability (rotating drum analysis), and laser light absorption (spectrophotometry). Bulk samples were characterised for microstructure (SEM), chemical composition (X-ray fluorescence spectrometry—XRF), porosity (computed tomography—CT) and mechanical properties (tensile, hardness). The powder was reused in subsequent processes without adding (recycling/rejuvenation) virgin powder (collective ageing powder reuse strategy). All tested powders (powders P0–P4) and bulk samples (series S0–S3) show repeatable properties, with changes observed within error limits. Samples manufactured within the fifth reuse cycle (series S4) showed some mean value changes of measured characteristics indicating initial degradation. However, these changes also mostly fit within error limits. Therefore, the collective ageing powder reuse strategy is considered to give repeatable LPBF process results and is recommended for the AlSi7Mg0.6 alloy within at least five consecutive LPBF processes.     

Cyclic Deformation Behavior of Additive-Manufactured IN738LC Superalloys from Virgin and Reused Powders

In laser powder bed fusion (L-PBF), most powders are not melted in the chamber and collected after the printing process. Powder reuse is appreciable without sacrificing the mechanical properties of target components. To understand the influences of powder reuse on mechanical performance, a nickel-based superalloy, IN738LC, was investigated. Powder morphology, microstructure and chemical compositions of virgin and reused powders were characterized. An increase in oxygen content, generally metallic oxides, was located on the surface of powders. Monotonic tensile and cyclic fatigue were tested. Negligible deterioration in strength and tensile ductility were found, while scattered fatigue performance with regard to fatigue life was shown. Deformation and fatigue crack propagation mechanisms were discussed for describing the powder degradation effects.     

The Implementation of Industrial Byproduct in Malaysian Peat Improvement: A Sustainable Soil Stabilization Approach

Peat is a well-known problematic soil associated with poor engineering properties. Its replacement with an expensive competent foundation material is practiced for road embankment construction which is costly and causes greenhouse gas emissions. Therefore, this paper investigated the effectiveness of a byproduct from a metal industry (silica fume) to stabilize peat along with ordinary Portland cement (OPC) through a series of experimental tests. After peat-indexed characterization, a number of standard compaction and mechanical tests were performed on the stabilized and parent peat. For this purpose, nine designated mixes were prepared possessing various combinations of silica fume (SF) and 10–20% OPC. Unconfined compressive strength (UCS) and California Bearing Ratio (CBR) tests were carried out after 7, 14, and 28 days of curing to assess strength enhancement and binder effectiveness, and the microstructural evolution induced by the binders was examined with scanning electron microscopy (SEM). The analysis revealed a substantial improvement in mechanical properties with the incorporation of SF and OPC, ultimately meeting the minimum strength requirement for highway construction (i.e., 345 kPa). A peak UCS of 1063.94 kPa was recorded at 20% SF, and an unsoaked CBR value of 42.95 was observed using 15% SF and 15% OPC after 28 days of curing. Furthermore, the increasing percentage of hydraulic binders exhibited brittle, collapsible failure, while the microstructural study revealed the formation of a dense matrix with a refined pore structure in the treated peat. Finally, a significant statistical analysis was carried out by correlating the test parameters. In this way, rather than stockpiling and dumping, an industrial byproduct was implemented in peat stabilization in an eco-friendly manner.     

Comparison of performance characteristics between new and reprocessed electrophysiology catheters

Objective Electrophysiology (EP) catheter reprocessing is widespread and previous studies have examined clinical performance, sterility and safety of these reprocessed devices. Here we compare the intrinsic engineering characteristics, electrical, mechanical and safety, between new and reprocessed devices. Materials and methods New (58 devices) and clinically used (five times)/reprocessed (165 devices) EP catheters from five manufacturers were employed to examine and compare catheter electrode continuity, electrode isolation, electrical leakage current, shaft torsion and stiffness characteristics as well as tip buckling and bond strengths. Results Electrode continuity, isolation and leakage currents for both new and reprocessed EP catheters were within acceptance criteria for electrode continuity (<30 Ω) and shaft electrical leakage (<0.5 mA) as well as electrode isolation (>200 Ω). In addition, reprocessed catheters were equivalent when compared with their new counterparts. While catheter shaft torque forces varied five fold amongst manufacturers, comparison between new and reprocessed devices within a manufacturer showed no significant differences. Likewise shaft stiffness showed no significant difference between new and reprocessed devices. Average tip buckling forces for all catheters were substantially below the acceptance criteria of 0.45 lb (between 0.04 and 0.1 lb) with differences between new and reprocessed catheters not being significant. All bond strengths for both new and reprocessed catheters exceeded the acceptance criteria specified in ISO 10555-1. Conclusions This study found that reprocessed EP catheters which had undergone five actual clinical use/reprocessing cycles met and exceeded acceptance criteria specified by industry standards as well as individual manufacturer’s criteria for both electrical and safety characteristics. We conclude that reprocessed EP catheters exhibit electrical, mechanical and safety characteristics which are equivalent to their new counterparts.     

Reuse of Ti6Al4V Powder and Its Impact on Surface Tension,Melt Pool Behavior and Mechanical Properties of Additively Manufactured Components

The quality and characteristics of a powder in powder bed fusion processes play a vital role in the quality of additively manufactured components. Its characteristics may influence the process in various ways. This paper presents an investigation highlighting the influence of powder deterioration on the stability of a molten pool in a laser beam powder bed fusion (LB-PBF, selective laser melting) process and its consequences to the physical properties of the alloy, porosity of 3D-printed components and their mechanical properties. The intention in this was to understand powder reuse as a factor playing a role in the formation of porosity in 3D-printed components. Ti6Al4V (15 μm–45 μm) was used as a base material in the form of a fresh powder and a degraded one (reused 12 times). Alloy degradation is described by possible changes in the shape of particles, particle size distribution, chemical composition, surface tension, density and viscosity of the melt. An approach of 3D printing singular lines was applied in order to study the behavior of a molten pool at varying powder bed depths. Single-track cross-sections (STCSs) were described with shape parameters and compared. Furthermore, the influence of the molten pool stability on the final density and mechanical properties of a material was discussed. Electromagnetic levitation (EML) was used to measure surface tension and the density of the melt using pieces of printed samples. It was found that the powder degradation influences the mechanical properties of a printed material by destabilizing the pool of molten metal during printing operation by facilitating the axial flow on the melt along the melt track axis. Additionally, the observed axial flow was found to facilitate a localized lack of fusion between concurrent layers. It was also found that the surface tension and density of the melt are only impacted marginally or not at all by increased oxygen content, yet a difference in the temperature dependence of the surface tension was observed.     

Influence of Polypropylene,Glass and Steel Fiber on the Thermal Properties of Concrete

The variety of approaches to tackle climate change reflects the size of this global problem. No technology will act as a panacea to cure the greenhouse gas emissions problem, but new building materials with byproducts or even wastes have the potential to play a major role in reducing the environmental impacts of the building sector. In this study, three potential solutions of concrete with dispersed reinforcement in the form of recycled fibers (polypropylene, glass and steel) were examined. The aim is to present a detailed analysis of the thermal properties of new building materials in an experimental approach. Concrete mixtures were prepared according to a new, laboratory-calculated recipe containing granite aggregate, a polycarboxylate-based deflocculant, Portland cement (52.5 MPa) and fibers. This experimental work involved three different contents of each fiber (0.5%, 0.75% and 1.0 wt.%), and all tests were carried after the complete curing cycle of concrete (28 days).     

Anévrismes intracrâniens et sclérose tubéreuse de Bourneville : une association rare

Introduction

Tuberous sclerosis is an autosomal dominant inherited phakomatosis. It is associated with a wide variety of central nervous system abnormalities, but intracranial aneurysms are rare.

Case report

We report a 34-year-old patient fulfilling the diagnostic criteria of tuberous sclerosis in association with intracranial aneurysm.

Discussion

This association has been reported in only 17 other cases of tuberous sclerosis. We discuss the etiopathogenic mechanisms, preferential localizations and the various therapeutic propositions.