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The manipulation and control of free-standing liquid film drainage dynamics is of paramount importance in many technological fields and related products, ranging from liquid lenses to liquid foams and 2D structures. In this context, we theoretically design and introduce a device where we can reversibly drive flow regime switch between viscous-capillary and viscous-gravity in a thin free-standing liquid film by altering its shape, allowing us to manipulate and stabilize the film thickness over time. The device, which mainly consists of a syringe pump, a pressure transducer, and a 3D-printed cylinder, is coupled with a digital holography setup to measure, in real time, the evolution of the local film thickness map, revealing characteristic features of viscous-capillary and viscous-gravity driven drainage regimes. By using polyvinyl alcohol/water concentrated solutions, we are also able to produce viscoelastic membranes after manipulation and water evaporation, which presents manipulation history-dependent geometrical properties. Furthermore, using a system composed of carboxymethyl cellulose, water, and rod-like zinc oxide nanoparticles, we show a clear effect of film manipulation on particle rearrangement. We believe this device could represent a starting point for the development of a useful and practical tool to study thin liquid film dynamics and to produce novel (patterned) 2D structures for the numerous scientific and technical fields where they are of use.

Plastic foams, near-ubiquitous in everyday life and industry, show properties that depend primarily on density. Density measurement, although straightforward in principle, is not always easy. As such, while several methods are available, plastic foam industry is not yet supported with a standard technique that effectively enables to control density maps. To overcome this issue, this paper proposes Terahertz (THz) time-of-flight imaging using normal reflection measurements as a fast, relatively cheap, contactless, non-destructive and non-dangerous way to map plastic foam density, based on the expected relationship between density and refractive index. The approach is demonstrated in the case of polypropylene foams. First, the relationship between the estimated effective refractive index and the polypropylene foam density is derived by characterizing a set of carefully crafted samples having uniform density in the range 70-900 kg/m 3 . The obtained calibration curve subtends a linear relationship between the density and the refractive index in the range of interest. This relationship is validated against a set of test samples, whose estimated average densities are consistent with the nominal ones, with an absolute error lower than 10 kg/m 3 and a percentage error on the estimate of 5%. Exploiting the calibration curve, it is possible to build quantitative images depicting the spatial distribution of the sample density. THz images are able to reveal the non-uniform density distribution of some samples, which cannot be appreciated from visual inspection. Finally, the complex spatial density pattern of a graded foam sample is characterized and quantitatively compared with the density map obtained via X-ray microscopy. The comparison confirms that the proposed THz approach successfully determines the density pattern with an accuracy and a spatial scale variability compliant with those commonly required for plastic foam density estimate., (© 2024. The Author(s).)

Background: Although most patients with moderate chronic kidney disease (CKD) are managed exclusively in primary care (PC), no data on blood pressure (BP) control in this setting are available. We compared hypertension management in patients with CKD followed up in PC and nephrology tertiary care (TC)., Methods: We studied hypertensive patients with estimated glomerular filtration rates (eGFRs) of 15 to 60 mL/min/1.73 m2 (0.25 to 1.00 mL/s) exclusively followed up for at least 1 year in PC (n = 259) or TC (n = 186)., Results: PC compared with TC patients were characterized by older age (73 +/- 10 versus 65 +/- 14 years; P < 0.0001), greater prevalences of previous cardiovascular events (59% versus 32%; P < 0.0001) and diabetes (36% versus 23%; P = 0.005), and slightly greater eGFRs (37 +/- 10 versus 34 +/- 11 mL/min/1.73 m2 ; P = 0.005). They showed higher BP levels (143 +/- 15/82 +/- 7 versus 136 +/- 18/78 +/- 11 mm Hg; P < 0.0001), with a lower prevalence of BP target (5.8% [95% confidence interval (CI), 2.9 to 8.6] versus 21.5% [95% CI, 15.6 to 27.4]; P < 0.0001). The risk for not achieving BP target in PC was 2.6 times greater, independently from age, sex, diabetes, and eGFR. Fewer antihypertensive drugs were prescribed in PC (1.9 +/- 1.1 versus 2.5 +/- 1.1; P < 0.0001). In both groups, inhibitors of the renin-angiotensin system were the most frequently prescribed drugs (>84%), followed by diuretics (50%). However, family physicians almost exclusively prescribed hydrochlorothiazide, whereas nephrologists preferentially prescribed furosemide, administered at a higher dose than in PC (47 +/- 41 versus 28 +/- 21 mg/d; P = 0.004)., Conclusion: Control of CKD-related hypertension is significantly worse in PC despite a greater cardiovascular risk. Barriers to optimal BP control likely are represented by a low number of drugs and inadequate diuretic therapy.

An assessment was made of the fourth heart sound as a non-invasive clinical and instrumental aid in the diagnosis of latent cardiac insufficiency. The sound was recorded in various decubitus positions in a series of healthy subjects and patients with recent and past infarction, under basal conditions, after exercise on the cycle ergometer, and after digitalis i.v. Persistence of the fourth sound in the standing position was noted in nearly all infarct patients, while its incidence decreased significantly after digitalis. It is felt that this finding can be interpreted as evidence of the non-existence of latent heart failure. Its further investigation and correlation with other invasive and non-invasive instrumental examinations is proposed.