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Spatially resolved GARField NMR has been used to follow the ingress of water into previously dried Portland cement concrete and mortar samples. It is shown that the amount of capillary water in the surface layers of different samples after 1 day of capillary absorption exceeds the amount found before drying but that over the subsequent 7 days the amount of capillary water decreases once more, even though the external source of water is maintained. The hydrate gel pore water was additionally tracked in the mortars. It shows complementary behaviour. The data is discussed in terms of C–S–H swelling. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines saturated control of a general class of uncertain nonlinear systems with time-delayed actuation and additive bounded disturbances. The bound on the control is known a priori and can be adjusted by changing the feedback gains. A Lyapunov-based stability analysis utilizing Lyapunov–Krasovskii (LK) functionals is provided to prove uniformly ultimately bounded tracking despite uncertainties in the dynamics. A numerical example is presented to demonstrate the performance of the controller. [Copyright &y& Elsevier]

Rinsing is an important part of the cleaning procedure applied to the spiral-wound membrane (SWM) modules in the dairy industry. In this work, we numerically investigated the displacement of non-Newtonian reconstituted milk protein concentrates in a feed spacer channel using OpenFOAM and compared the results with experimental data obtained in an SWM pilot plant. The model consists of the classical mass and momentum balance equations for an incompressible viscous mixture coupled with an advection-diffusion equation for the milk concentration. The power-law model was utilized to describe the shear-thinning viscosity of the milk protein concentrates. The shear-thinning behavior was further assumed to depend on the milk protein content. The calculations confirmed significantly shorter rinsing times and lower mixed-phase volumes for lower milk protein concentrations. The rinsing time can further be lowered by increasing the volumetric flow rate. Through the numerical simulations, we identified nearly inaccessible zones behind the filament crossings that prolong the rinsing process. • 3D simulation of displacement of milk protein concentrate (MPC) in spacer-filled channel. • Viscosity of MPC strongly decreases at beginning of rinsing procedure. • Identification of hardly accessible zones behind filament crossings. • Lower mixed-phase volumes for smaller milk protein concentrations and higher flow rates. • Good agreement with rinsing data obtained in spiral wound membrane module. [ABSTRACT FROM AUTHOR]

To establish a simple and widely accessible technique for rapidly selecting high producing Chinese hamster ovary (CHO) cells engineered to express a monoclonal antibody (mAb), we have exploited the transient display of recombinant protein on their cell surface. In combination with magnetic bead-based methods, we demonstrate the ability to select for cells of high productivity in the absence of any metabolic-based selection method. This technique is sufficient to obtain genetically stable engineered CHO cells via a single step of cell subcloning and yields sought-after stable, high IgG producing clonal cell lines. This technique may also be applied to other types of cells as well as polyclonal Ab cell pools. [ABSTRACT FROM AUTHOR]

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a rare disease caused by the deposition of amyloid fibrils in the myocardium, resulting from either a wild-type form or genetic mutations. Conclusions This retrospective analysis demonstrated increased 30-day HF readmissions and mortality among CA patients compared to HF patients covered by Medicare Advantage. [Extracted from the article]

The development, manufacturing and commercialization of nanomaterials require traceable characterisation processes for quality control and safety of both the exposed workers and final customers. Even if the production batches are considered to be compliant with the industrial applications intended by manufacturers, it is necessary to study the reproducibility of the manufacturing process of nanomaterials independently, so as to determine the variability of key physico-chemical properties of nano-objects from one batch to another. In this study, a metrological approach was employed, using different traceable analytical techniques (X-Ray Diffraction, Transmission Electron Microscopy, Nitrogen physisorption with Brunauer–Emmett–Teller method, X-Ray Fluorescence, Scanning Mobility Particle Sizer and Aerodynamic Particle Sizer) to develop robust, reproducible and statistical methods to evaluate the impact of batch variability on physico-chemical properties of manufactured titanium dioxide and silicon dioxide nano-powders (crystalline structure, crystallite size, primary particle size, specific surface area, chemical composition and the dustiness of nanopowders). Five references of manufactured titanium dioxide nanoparticles and silicon dioxide nanoparticles were characterized with the developed measurement protocols. The reproducibilities of five batches by reference were overall inferior to 10% for crystalline structures, primary particle sizes, specific surface areas and the chemical composition of major components (TiO 2 and SiO 2 ) of the nanopowders studied (k = 1). As for the size distributions of released particles from dustiness tests, reproducibility for the modal and mean diameters ranged between 2% and 27%. Moreover, a large variation of nanopowder dustiness was obtained for the same material type (TiO 2 or SiO 2 ). This could point out that the physico-chemical properties of nanopowders, linked to the manufacturing process, have a strong impact on the dustiness parameter. [ABSTRACT FROM AUTHOR]

While no gold standard exists for the management of Achilles tendon ruptures, surgical repair is common in healthy and active patients. Minimally invasive repair methods have become increasingly popular, while biomechanical equivalency hasn't been proven yet. A mid-substance Achilles tendon rupture was created 6 cm proximal to the calcaneal insertion in 27 fresh-frozen cadaveric ankles. Specimens were randomly allocated to 1 of 3 repair techniques: Huttunen et al. (2014) (1) PARS Achilles Jig System, Nyyssönen et al. (2008) (2) Achilles Midsubstance SpeedBridge™, Schipper and Cohen (2017) (3) Dresdner Instrument and subsequently subjected to cyclic loading with 250 cycles each at 1 Hz with 4 different loading ranges (20–100 N, 20–200 N, 20–300 N, and 20–400 N). After 250 cycles no significant differences in elongation were observed between PARS and Dresdner Instrument(p = 1.0). Furthermore, SpeedBridge™ repairs elongated less than either Dresdner Instrument (p = 0.0006) or PARS (p = 0.102). Main elongation (85%) occurred within the first 10 cycles with a comparable elongation in between 10 and 100 and 100–250 cycles. While all repairs withstood the first 250 cycles of cyclic loading from 20 to 100 N, only the PARS (468 ± 175) and Midsubstance SpeedBridge™ (538 ± 208) survived more cycles. Within all 3 groups suture cut out was seen to be the most common failure mechanism. Within all groups early repair elongation was seen. While this was least obvious within the SpeedBridge™ technique, ultimate strengths of repairs (cycles to failure) were comparable across PARS and SpeedBridge™ with a decline in the Dresdner Instrument group. • All repairs survived the first 250 cycles, while none survived all 4 loading stages. • Dresdner Instrument repair completed significantly less cycles prior to failure. • Suture cutout at the suture-tendon interface was the primary failure mechanism. • The model presents a simplified representation of the biomechanical characteristics. [ABSTRACT FROM AUTHOR]

Tropheryma whipplei has been hypothesized to be able to cause diarrhoea, but data from young children are scarce. In this hospital-based case–control study 534 stool samples of children aged between 2 months and 15 years from rural Ghana were analysed for the presence of T. whipplei. Overall stool prevalence of T. whipplei was high (27.5%). Although there was no difference in T. whipplei carriage overall between cases and controls, cases aged between 0 and 12 months carried T. whipplei in their stool twice as often as controls without diarrhoea. The results from this study may support the hypothesis that T. whipplei can cause diarrhoea in first-time infection. [ABSTRACT FROM AUTHOR]

• Compare uncertainty evaluation methodologies of very small flow rates, close to zero. • Monte Carlo approach is a convenient alternative to the GUM uncertainty evaluation. • For a significant number of negative values, the Bayesian approach works better. • Microflow measurements are essential in many fields of industry and medicine. • Methods under development to measure below 100 nL/min, e.g., interferometry. The importance of measurement quality cannot be over emphasized in medical applications, as one is dealing with life issues and the wellbeing of society, from oncology to new-borns, and more recently to patients of the COVID-19 pandemic. In all these dire situations, the accuracy of fluid delivered according to a prescribed dose can be critical. Microflow applications are growing in importance for a wide variety of scientific fields, namely drug development and administration, Organ-on-a-Chip, or bioanalysis, but accurate and reliable measurements are a tough challenge in micro-to-femto flow operating ranges, from 2.78 × 10−4 mL/s down to 2.78 × 10−7 mL/s (1000 μL/h down to 1 μL/h). Several sources of error have been established such as the mass measurement, the fluid evaporation dependent on the gravimetric methodology implemented, the tube adsorption and the repeatability, believed to be closely related to the operating mode of the stepper motor and drive screw pitch of a syringe pump. In addition, the difficulty in dealing with microflow applications extends to the evaluation of measurement uncertainty which will qualify the quality of measurement. This is due to the conditions entailed when measuring very small values, close to zero, of a quantity such as the flow rate which is inherently positive. Alternative methods able to handle these features were developed and implemented, and their suitability will be discussed. [ABSTRACT FROM AUTHOR]