Tuning of the characteristics of Au nanoparticles produced by solid target laser ablation into water by changing the irradiation parameters.

We report the production of Au nanoparticles with different average sizes and size distributions, by laser ablation of a solid Au target into pure deionized water. Tuning laser parameters such as pulse duration, energy, and wavelength is possible to tune the size and the size distributions of the produced nanoparticles into the liquid. We demonstrate the possibility of production of highly monodispersed colloidal solutions, in which the average nanoparticle size ranges from 3 to 10 nm, using laser pulses of ns duration. Laser ablation using fs laser pulses can also produce very small nanoparticles, although a small population of bigger nanoparticles is always present. Low and high-resolution transmission electron microscopy (TEM), in combination with UV-Vis spectroscopy have been employed for the characterization of our samples

Out-of-Plane Biphilic Surface Structuring for Enhanced Capillary-Driven Dropwise Condensation

Rapid and sustained condensate droplet departure from a surface is key towards achieving high heat transfer rates in condensation, a physical process critical to a broad range of industrial and societal applications. Despite progress in enhancing condensation heat transfer through inducing its dropwise mode with hydrophobic materials, sophisticated surface engineering methods that can lead to further enhancement of heat transfer are still highly desirable. Here, by employing a three-dimensional, multiphase computational approach, we present an effective out-of-plane biphilic surface topography, that reveals an unexplored capillarity-driven departure mechanism of condensate droplets. This texture consists of biphilic diverging micro-cavities wherein a matrix of small hydrophilic spots is placed at their bottom, that is, amongst the pyramid-shaped, superhydrophobic micro-textures forming the cavities. We show that an optimal combination of the hydrophilic spots and the angles of the pyramidal structures can achieve high deformational stretching of the droplets, eventually realizing an impressive slingshot-like droplet ejection process from the texture. Such a droplet departure mechanism has the potential to reduce the droplet ejection volume and thus enhance the overall condensation efficiency, compared to coalescence-initiated droplet jumping from other state-of-the-art surfaces. Simulations have shown that optimal pyramid-shaped biphilic micro-structures can provoke droplet self-ejection at low volumes, up to 56% lower compared to superhydrophobic straight pillars, revealing a promising new surface micro-texture design strategy towards enhancing condensation heat transfer efficiency and water harvesting capabilities

Implementation of Guidelines for the Management of Arterial Hypertension. The Impulsion Study

This study assessed the effects of a pilot best practice implementation enhancement program on the control of hypertension. We enrolled 697 consecutive known hypertensive patients with other vascular risk factors but free from overt vascular disease. There was no “control” group because it was considered unethical to deprive high-risk patients from “best medical treatment”. Following a baseline visit, previously trained physicians aimed to improve adherence to lifestyle measures and drug treatment for hypertension and other vascular risk factors. Both at baseline and at study completion (after 6 months), a 1-page form was completed showing if patients achieved treatment targets. If not, the reasons why were recorded. This program enhanced compliance with lifestyle measures and increased the use of evidence-based medication. There was a substantial increase in the number of patients who achieved treatment targets for blood pressure (p<0.0001) and other vascular risk factors. In non-diabetic patients (n=585), estimated vascular risk (PROCAM risk engine) was significantly reduced by 41% (p<0.0001). There was also a 12% reduction in vascular risk according to the Framingham risk engine but this did not achieve significance (p=0.07). In conclusion, this is the first study to increase adherence to multiple interventions in hypertensive patients on an outpatient basis, both in primary care and teaching hospitals. Simple, relatively low cost measures (e.g. educating physicians and patients, distributing printed guidelines/brochures and completing a 1-page form) motivated both physicians and patients to achieve multiple treatment goals. Further work is needed to establish if the improvement observed is sustained. [ClinicalTrials.gov NCT00416611]

Self-Sustained Cascading Coalescence in Surface Condensation

ISSN:1944-8244ISSN:1944-8252ISSN:1944-8244ISSN:1944-825