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When treating patients with Autism Spectrum Disorder (ASD) the doctor-patient relationship can be very challenging. The dentist is often forced to work under general anaesthesia or conscious sedation. Children with ASD are patients with an increased risk of caries due to poor oral hygiene, a cariogenic diet and the use of xerostomal drugs. In this work therapeutic strategies used to treat this kind of patients are evaluated and a new method to treat children with ASD is presented in order to increase awareness about this condition in the dental field.The Atlas Center (a non-profit organisation in Peurgia, Italy) has developed a software, called paINTeraction, that allows these special children to immerse themselves in a virtual reality with the help of an operator. Through this system the child can explore the dental office (and all its sounds and noises) before the real dental visit, thus connecting to the dental professional, achieving greater compliance and reducing anxiety.paINTeraction, with the use of digital technology tools, may be particularly well suited to introduce patients to the therapeutic environment, particularly in the dental setting.

– The most important prognostic factors in renal carcinoma are the stage and grade. World literature is full of information on new markers, the analysis of DNA with the cytofluorimetric method being foremost, as it allows the cell lines in the neoplasm to be assessed and at the same time the ploidy and cell cycle stages to be studied. We have found an excellent correlation between the ploidy and cell grade. After a preliminary study we can conclude that the method is easy to perform and to reproduce. The procedure is also interesting for retrospective studies which allow the pathologist to select the blocks to be examined, thereby avoiding those widely contaminated by hemorrhages or necrosis.

Postoperative infections continue to be one of the most frequent complications in hospitalized patients. The incidence of fungal infection has been steadily rising. While Candida albicans remains the most common yeast species isolated in hospitalized patients, other Candida species have been increasingly isolated.From 1996 to 2001, a prospective study of 500 consecutive lung surgery patients treated by the same surgical team was conducted to monitor the number of postoperative infections and to evaluate the epidemiology of bacterial and fungal infections.At least one postoperative infection developed in 18% of patients. Of the 51 patients who developed postoperative pneumonia, 24 underwent microbiological examination of sputum. In 19 of them, the culture yielded isolates of one or more Candida species. Slightly under half of patients (47%) with cultures positive for mycetes received treatment with fluconazole until the clinical infection resolved. The drug was well tolerated by all treated patients.The incidence of fungal infection has increased also at our center. In 19 of 24 patients with postoperative pneumonia, sputum cultures yielded Candida species isolates. Many factors may be contributing to the rise in fungal infections after surgery. As pneumonia caused by Candida led to a significantly longer length of hospital stay in our case series, we draw attention to the importance of early diagnosis of postoperative mycotic lung disease in order to institute timely and targeted therapy.

Introduction and objectives Failure of compliance with the medical regimen is one of the major risk factors associated with morbidity and mortality in heart transplantation patients. The aim of this study is to evaluate the influence of some psychosocial factors, such as the presence of pre-transplant psychiatric disorders, and coping strategies and family support measured after 12 months, in the compliance with the medical regimen in cardiac transplantation patients. Methods A prospective observational study was conducted over a period of 16 months to evaluate 22 subjects included in a heart transplantation program. Patients were assessed in the pre-transplant period and one year after transplantation. The evaluation collected medical history and sociodemographic data, clinical measurement of depression and anxiety, a structured psychiatric interview, coping strategies, family function questionnaire, and a tool designed to measure the compliance with the medical regimen. Results More than one-quarter (27%) of patients had a psychiatric disorder in the pre-transplant evaluation. The most frequently used coping strategies were acceptance and positive re-interpretation. Correlation analysis showed that there is a greater non-compliance with less family support and greater use of interpersonal coping strategies. No correlation was found between psychiatric conditions and compliance with guidelines. The overall percentage of non-compliance was 36.6%. Conclusions It has been shown that family support is an important factor associated with compliance with the medical regimen in patients with cardiac transplantation and, despite receiving adequate support, there is a high rate of non-compliance. © 2013 Elsevier España, S.L. All rights reserved.

The case of a 56-year-old man with contemporary benign granular cell tumour of the oesophagus and stomach is reported. Surgical resection of the oesophagus and stomach was performed after the diagnosis of squamous cell carcinoma on a superficial oesophageal biopsy which showed a pseudo-epitheliomatous hyperplasia of the stratified squamous epithelium covering the oesophageal Granular Cell Tumour (GCT). Hyperplasia was also found in the overlying gastric mucosa. Eight GCTs of the oesophagus, observed between 1980 and 1985, were reevaluated to compare the neoplastic characteristics and the occurrence of overlying epithelial hyperplasia. Only one patient was female; three had multiple oesophageal tumours and four showed pseudo-epitheliomatous hyperplasia. A review of the literature is included with emphasis on the rare cases of multiple GCTs. The association of chronic alcoholism with GCT of the gastro-intestinal tract is also stressed.

Hypothesis: Characterizing the microstructure of an ice/surface interface and its effect on the icephobic behavior of surfaces remains a significant challenge. Introducing X-ray Computed Tomography (XCT) can provide unprecedented insights into the internal (porosity) and interfacial structures, i.e. wetting regime, between (super)hydrophobic surfaces and ice by visualizing these optically inaccessible regions. Experiments: Frozen droplets with controlled volume were deposited on top of metallic and polymeric substrates with different levels of wettability. Different modes of XCT (3D and 4D) were utilized to obtain information on the internal and interfacial structure of the ice/surface system. The results were supplemented by conventional surface analysis techniques, including optical profilometry and contact angle measurements. Findings: Using XCT on ice/surface systems, the 3D and 4D (imaging with temporal resolution) structural information can be visualized. From these datasets, qualitative and quantitative results were obtained, not only for characterizing the interface but also for analyzing the entire droplet/surface system, e.g., measurement of porosity size, shape, and location. These results highlight the potential of XCT in the characterization of both droplets and substrates and proves that the technique can aid to develop hydrophobic surfaces for use as icephobic materials.

Controlling water transport and management is crucial for continuous and reliable system operation in harsh weather conditions. Passive strategies based on nonwetting surfaces are desirable, but so far, the implementation of superhydrophobic coatings into real-world applications has been limited by durability issues and, in some cases, lack of compliance with environmental regulations. Inspired by surface patterning observed on living organisms, in this study we have developed durable surfaces based on contrast wettability for capillary-driven water transport and management. The surface fabrication process combines a hydrophobic coating with hard-anodized aluminum patterning, using a scalable femtosecond laser microtexturing technique. The concept targets heavy-duty engineering applications; particularly in aggressive weather conditions where corrosion is prevalent and typically the anodic aluminum oxide-based coating is used to protect the surface from corrosion, the concept has been validated on anodic aluminum oxide coated aluminum alloy substrates. Such substrates with contrast wettable characteristics show long-term durability in both natural and lab-based artificial UV and corrosion tests where superhydrophobic coatings tend to degrade.

Structural characterization techniques are fundamental to correlate the material macro-, nano-, and molecular-scale structures to their macroscopic properties and to engineer hierarchical materials. Here, we combine X-ray transmission with scanning small-and wide-angle X-ray scattering (sSWAXS) to investigate ultraporous and lightweight biopolymer-based foams using cellulose nanofibrils (CNFs) as building blocks. The power of multimodal sSWAXS for multiscale structural characterization of self-assembled CNFs is demonstrated by spatially resolved maps at the macroscale (foam density and porosity), at the nanoscale (foam structural compactness, CNF orientation in the foam walls, and CNF packing state), and at the molecular scale (cellulose crystallite dimensions). Specifically, we compare the impact of freeze-thawing-drying (FTD) fabrication steps, such as static/stirred freezing and thawing in ethanol/water, on foam structural hierarchy spanning from the molecular to the millimeter scale. As such, we demonstrate the potential of X-ray scattering imaging for hierarchical characterization of biopolymers., Biomacromolecules, 23 (3)

Ice formation on surfaces is a common phenomenon occurring in the presence of water at temperatures below the freezing point, and can negatively impact many aspects of our lives. Atmospheric icing, which forms due to the natural presence of water as small liquid drops or vapor in the air, can cause damage to ground transportation, airplanes, power lines, and communication systems (e.g., telephone and cable television line operations) and other man-made structures and devices.

Electrodeposition is an effective and scalable method to grow desired structures on solid surfaces, for example, to impart superhydrophobicity. Specifically, copper microcrystals can be grown using electrodeposition by controlling deposition parameters such as the electrolyte and its acidity, the bath temperature, and the potential modulation. The aim of the present work is the fabrication of superhydrophobic copper-based surfaces by electrodeposition, investigating both surface properties and assessing durability under conditions relevant to real applications. Accordingly, copper-based layers were fabricated on Au/Si(100) from Cu(BF4)2 precursor by electrodeposition, using cyclic voltammetry and square-pulse voltage approaches. By increasing the bath temperature from 22 °C to 60 °C, the growth of various structures, including micrometric polyhedral crystals and hierarchical structures, ranging from small grains to pine-needle-like dendrite leaves, has been demonstrated. Without any further physical and/or chemical modification, samples fabricated with square-pulse voltage at 60 °C are superhydrophobic, with a contact angle of 160° and a sliding angle of 15°. In addition, samples fabricated from fluoroborate precursor are carefully compared to those fabricated from sulphate precursor to compare chemical composition, surface morphology, wetting properties, and durability under UV exposure and hard abrasion. Results show that although electrodeposition from fluoroborate precursor can provide dendritic microstructures with good superhydrophobicity properties, surfaces possess lower durability and stability compared to those fabricated from the sulphate precursor. Hence, from an application point of view, fabrication of copper superhydrophobic surfaces from sulphate precursor is more recommended.

Contact angle measurement is an effective way to investigate solid surface properties. The introduction of low-cost digital cameras, as well as software and libraries for image analysis, has made contact angle measurement potentially accessible to every laboratory. In this review, we provide a comparison of the main methods developed to evaluate contact angle from digital images, including the so-called Young-Laplace method, the circle and polynomial fittings, as well as the mask method. All methods have been implemented and compared analyzing virtual and real drop images in an open-source software, Dropen, developed as an app in MATLAB environment. The code enables single image analysis evaluation, for the robust automatic identification of the contact points and contact angle evaluation, with the goal of minimizing user inputs, automatizing the process and facilitating measurements for all users, from less experienced to advanced wetting experts. Dropen and its code are made available at BOA, the Bicocca Open Access public repository, for use and further development.

An oil shell encapsulating a water drop promotes rebound after impact on a solid surface, irrespective of substrate wettability., Drop impact on solid surfaces is encountered in numerous natural and technological processes. Although the impact of single-phase drops has been widely explored, the impact of compound drops has received little attention. Here, we demonstrate a self-lubrication mechanism for water-in-oil compound drops impacting on a solid surface. Unexpectedly, the core water drop rebounds from the surface below a threshold impact velocity, irrespective of the substrate wettability. This is interpreted as the result of lubrication from the oil shell that prevents contact between the water core and the solid surface. We combine side and bottom view high-speed imaging to demonstrate the correlation between the water core rebound and the oil layer stability. A theoretical model is developed to explain the observed effect of compound drop geometry. This work sets the ground for precise complex drop deposition, with a strong impact on two- and three-dimensional printing technologies and liquid separation.

Drop interaction with solid surfaces upon impact has been attracting a growing community of researchers who are focusing more and more on ‘complex’ surfaces and ‘complex’ drops. Recently, we are observing an emerging research trend related to the investigation of compound drop impact. Compound drops consist of two or more distinct continuous phases sharing common interfaces, surrounded by a third phase. Examples are core–shell and Janus drops. In this review, we address the fundamental aspects of compound drop impact and discuss the current challenges related to experimental testing and numerical simulation of multiphase fluid systems. Furthermore, we provide a perspective on the technological relevance of understanding and controlling compound drop impact, ranging from 3D printing to liquid separation for water cleaning and oil remediation.

Superhydrophobic surfaces (SHS) show remarkable water repellency properties, and their use may have a tremendous impact for a plethora of applications, where liquid water accumulation needs to be controlled or minimised. However, the durability of SHS in operational conditions is a severe issue that currently represents a bottleneck for the technology transfer from laboratory to industrial applications. In the present work, we try to fill in the gap caused by the absence of a standard for evaluation for SHS durability, by developing a protocol for testing surface durability. The proposed protocol includes nine tests as follows: water immersion, acidic environment, alkaline environment, ionic solution, mechanical erosion, ultraviolet exposure, resistance to heating, alcohol immersion and hydrocarbon immersion. The protocol can serve to give an indication of surface robustness in a variety of potentially harmful environments, by providing a global figure of merit and ranking for different SHS and thereby allowing for identifying those surfaces fulfilling requirements for a specific application. To illustrate the protocol, we tested a SHS developed in-house by grafting of lauric acid molecules on an aluminum substrate. This article contains supporting information that is available online.

Separating petroleum hydrocarbons from water is an important problem to address in order to mitigate the disastrous effects of hydrocarbons on aquatic ecosystems. A rational approach to address the problem of marine oil-water separation is to disperse the oil with the aid of surfactants in order to minimize the formation of large slicks at the water surface and to maximize the oil-water interfacial area. Here we investigate the fundamental wetting and transport behavior of such surfactant-stabilized droplets and the flow conditions necessary to perform sieving and separation of these stabilized emulsions. We show that, for water-soluble surfactants, such droplets are completely repelled by a range of materials (intrinsically underwater superoleophobic) due to the detergency effect; therefore, there is no need for surface micro-/nanotexturing or chemical treatment to repel the oil and prevent fouling of the filter. We then simulate and experimentally investigate the effect of emulsion flow rate on the transport and impact behavior of such droplets on rigid meshes to identify the minimum pore opening (w) necessary to filter a droplet with a given diameter (d) in order to minimize the pressure drop across the mesh-and therefore maximize the filtering efficiency, which is strongly dependent on w. We define a range of flow conditions and droplet sizes where minimum droplet deformation is to be expected and therefore find that the condition of w ≈ d is sufficient for efficient separation. With this new understanding, we demonstrate the use of a commercially available filter-without any additional surface engineering or functionalization-to separate oil droplets (d < 100 μm) from a surfactant-stabilized emulsion with a flux of ∼11,000 L m-2 h-1 bar-1. We believe these findings can inform the design of future oil separation materials.

Introduction: In this study,a novel numerical implementation for the adhesion of liquid droplets impacting normally on solid dry surfaces is presented. The advantage of this new approach, compared to the majority of existing models, is that the dynamic contact angle forming during the surface wetting process is not inserted as a boundary condition, but is derived implicitly by the induced fluid flow characteristics (interface shape) and the adhesion physics of the gas-liquid-surface interface (triple line), starting only from the advancing and receding equilibrium contact angles. These angles are required in order to define the wetting properties of liquid phases when interacting with a solid surface. Methodology: The physical model is implemented as a source term in the momentum equation of a Navier-Stokes CFD flow solver as an "adhesion-like" force which acts at the triple-phase contact line as a result of capillary interactions between the liquid drop and the solid substrate. The numerical simulations capture the liquid-air interface movement by considering the volume of fluid (VOF) method and utilizing an automatic local grid refinement technique in order to increase the accuracy of the predictions at the area of interest, and simultaneously minimize numerical diffusion of the interface. Results: The proposed model is validated against previously reported experimental data of normal impingement of water droplets on dry surfaces at room temperature. A wide range of impact velocities, i.e. Weber numbers from as low as 0.2 up to 117, both for hydrophilic (theta(adv) = 10 degrees-70 degrees) and hydrophobic (theta(adv) = 105 degrees-120 degrees) surfaces, has been examined. Predictions include in addition to droplet spreading dynamics, the estimation of the dynamic contact angle; the latter is found in reasonable agreement against available experimental measurements. Conclusion: It is thus concluded that the implementation of this model is an effective approach for overcoming the need of a pre-defined dynamic contact angle law, frequently adopted as an approximate boundary condition for such simulations. Clearly, this model is mostly influential during the spreading phase for the cases of low We number impacts (We < (similar to)80) since for high impact velocities, inertia dominates significantly over capillary forces in the initial phase of spreading. (C) 2014 Elsevier B.V. All rights reserved.

Understanding the interaction of supercooled metastable water with superhydrophobic surface textures is of fundamental significance for unraveling the mechanisms of icing as well as of practical importance for the rational development of surface treatment strategies to prevent icing. We investigate the problem of supercooled water drops impacting superhydrophobic textures for drop supercooling down to -17 degrees C and find that increased viscous effects significantly influence all stages of impact dynamics, in particular, the impact and meniscus impalement behavior, with severe implications to water retention by the textures (sticky versus rebounding drop) and possible icing. Viscous effects in water supercooling conditions cause a reduction of drop maximum spreading (similar to 25% at an impact speed of 3 m/s for a millimetric drop) and can significantly decrease the drop recoil speed when the meniscus partially penetrates into the texture, leading to an increase of the contact time up to a factor of 2 in supercooling conditions compared to room temperature. We also show that meniscus penetration upon drop impact occurs with full penetration at the center, instead of ring shape, common to room temperature drop impact. To this end, we describe an unobserved mechanism for superhydrophobicity breakdown: unlike for room temperature drops, where transition from bouncing to sticky (impaled) behavior occurs sharply at the condition of full texture penetration, with a bubble captured at the point of impact, under supercooled conditions, the full penetration velocity threshold is increased markedly (increasing by similar to 25%, from 2.8 to 3.5 m/s) and no bubble is entrapped. However, even though only partial texture penetration takes place, failure to completely dewet because of viscous effects can still prohibit complete supercooled drop rebound.

In this paper we present a simple but effective procedure to impart superhydrophobicity to aluminum through a one-step wet chemistry synthesis. The synthesis is performed in one step, thanks to simultaneous etching with NaOH and grafting with fluoroalkyl silane (FAS) molecules, which allow aluminum surface functionalization. By optimizing the proper amount of reagents, controlling the reaction batch temperature and particularly by allowing pre-activation of the solution, we showed that the process can be used turn into water repellant superhydrophobic surfaces four aluminum samples in sequence, using the same reaction batch. Also, if FAS is further added to the solution the procedure can impart superhydrophobicity to further aluminum samples. The synthesis with the optimized parameters is green and cost effective, since it was developed to minimize the use of both base and fluorinated molecules. In addition, it is easy to scale up to large area treatments and to industrial application, because the procedure is one-step, is reproducible, and allows multiple use of the same reaction batch, for the treatment of multiple samples. Finally, we show that not only the surfaces show excellent non-wetting properties in quasi-static conditions, with contact angles ∼150̊ and with very low contact angle hysteresis, ∼4̊, but also in dynamic conditions, as proved by means of drop impact analysis up to Weber number of 690.

The superhydrophobic behavior of nano-and microtextured surfaces leading to rebound of impacting droplets is of great relevance to nature and technology. It is not clear however, if and under what conditions this behavior is maintained when such surfaces are severely undercooled possibly leading to the formation of frost and icing. Here we elucidate key aspects of this phenomenon and show that the outcome of rebound or impalement on a textured surface is affected by air compression underneath the impacting drop and the time scale allowing this air to escape. Remarkably, drop impalement occurred at identical impact velocities, both at room and at very low temperatures (-30 C) and featured a ringlike liquid meniscus penetration into the surface texture with an entrapped air bubble in the middle. At low temperatures, the drop contact time and receding dynamics of hierarchical surfaces were profoundly influenced by both an increase in the liquid viscosity due to cooling and a partial meniscus penetration into the texture. For hierarchical surfaces with the same solid fraction in their roughness, minimizing the gap between the asperities (both at micro-and nanoscales) yielded the largest resistance to millimetric drop impalement. The best performing surface impressively showed rebound at-30 C for drop impact velocity of 2.6 m/s. © 2013 American Chemical Society.

In the development of anti/de-icing systems for aeronautics, wind turbines or telecommunication antennas to date, less attention is paid to coating strategies. The majority of studies dealing with coatings have focused mainly on reducing ice adhesion forces, to easily remove ice, once it has formed. In this study we focused on an alternative strategy that consists of promoting the shedding of liquid water as a way to reduce the total amount of water present on the surface that can freeze. Shedding of liquid from the surface can be enhanced by modification of surface wettability, by means of the application of superhydrophobic coatings, i.e. water repellent coatings, characterized by low water adhesion forces. To study the effect of superhydrophobic coatings on surfaces exposed to icing conditions, tests were performed in an open loop icing wind tunnel (IWT) on a standard NACA0021 airfoil in two different icing conditions. Three samples were used during the tests, each one is characterized by different wettability properties. To simulate the presence on anti/de-icing system, the wing was also equipped with an electrical heater, mounted at the inner side of the wing leading edge. Results from IWT tests demonstrated that surface wettability is an important controlling factor not only for reducing ice accretion on the wing, but also for reducing by up to 80% the energy required to avoid ice accretion on the wing. The findings from IWT tests as described, together with results from a previous work on drop shedding, reinforced the hypothesis that shedding of drops is the key controlling mechanism for an efficient icing mitigation strategy.

This paper presents an experimental study on water drop oblique impacts onto hydrophobic and superhydrophobic tilted surfaces, with the objective of understanding drop impact dynamics and the conditions for drop rebound on low wetting surfaces. Drop impact experiments were performed with millimetric water drops with Weber numbers in the range 25

Drop rebound is a spectacular event that appears after impact on hydrophobic or superhydrophobic surfaces but can also be induced through the so-called Leidenfrost effect. Here we demonstrate that drop rebound can also originate from another physical phenomenon, the solid substrate sublimation. Through drop impact experiments on a superhydrophobic surface, a hot plate, and solid carbon dioxide (commonly known as dry ice), we compare drop rebound based on three different physical mechanisms, which apparently share nothing in common (superhydrophobicity, evaporation, and sublimation), but lead to the same rebound phenomenon in an extremely wide temperature range, from $300\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ down to even below $\ensuremath{-}79\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$. The formation and unprecedented visualization of an air vortex ring around an impacting drop are also reported.

The shortcomings of the current formulation for calculating the adhesion force for drops and bubbles with noncircular contact lines are discussed. A general formulation to evaluate the adhesion force due to surface forces is presented. Also, a novel methodology, that is, IBAFA, image based adhesion force analysis, was developed to allow implementation of the general formulation. IBAFA is based on the use of multiple profile images of a drop. The images are analyzed (1) to accurately reconstruct the contact line shape, which is analytically represented by a Fourier cosine series, and (2) to measure contact angles at multiple locations along the contact line and determine the contact angle distribution based on a linear piecewise interpolation routine. The contact line shape reconstruction procedure was validated with both actual experiments and simulated experiments. The procedure for the evaluation of the adhesion force was tested using simulated experiments with synthetic drops of known shapes. A comparison with current methods showed that simplifying assumptions (e.g., elliptical contact line or linear contact angle distribution) used in these methods result in errors up to 76% in the estimated adhesion force. However, the drop adhesion force evaluated using IBAFA results in small errors on the order of 1%.

Among the measurement and control systems of gas turbine engines, a recent new issue is the possibility of performing unsteady pressure measurements to detect flow anomalies in an engine or to evaluate loads on aerodynamic surfaces. A possible answer to this demand could be extending the use of well known and widely used transmission line systems, which have been applied so far to steady monitoring, to unsteady measurements thanks to proper dynamic modeling and compensation. Despite the huge number of models existing in the literature, a novel method has been developed, which is at the same time easy-to-handle, flexible and capable of reproducing the actual physics of the problem. Furthermore, the new model is able to deal with arbitrary complex networks of lines and cavities, and thus its applicability is not limited to series-connected systems. The main objectives of this paper are to show the derivation of the model, its validation against experimental tests and example of its applicability.

The present work is focused on the water drop impact at high impact Weber numbers (up to We=1100) on surfaces with a good (hydrophobic, 100° 135° and Δθ