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The present work compiles a review on drinking waterborne outbreaks, with the perspective of production and distribution of microbiologically safe water, during 2000–2014. The outbreaks are categorised in raw water contamination, treatment deficiencies and distribution network failure. The main causes for contamination were: for groundwater, intrusion of animal faeces or wastewater due to heavy rain; in surface water, discharge of wastewater into the water source and increased turbidity and colour; at treatment plants, malfunctioning of the disinfection equipment; and for distribution systems, cross-connections, pipe breaks and wastewater intrusion into the network. Pathogens causing the largest number of affected consumers were Cryptosporidium, norovirus, Giardia, Campylobacter, and rotavirus. The largest number of different pathogens was found for the treatment works and the distribution network. The largest number of affected consumers with gastrointestinal illness was for contamination events from a surface water source, while the largest number of individual events occurred for the distribution network.

A range extender (RE) is a device used in electric vehicles (EVs) to generate electricity on-board, enabling them to significantly reduce the number of required batteries and/or extend the vehicle driving range to allow occasional long trips. In the present work, an efficiency-oriented RE based on a small motorcycle engine modified to the efficient over-expanded cycle, was analyzed, tested and simulated in a driving cycle. The RE was developed to have two points of operation, ECO: 3000 rpm, very high efficiency with only 15 kW; and BOOST: 7000 rpm with 35 kW. While the ECO strategy was a straightforward development for the over-expansion concept (less trapped air and a much higher compression ratio) the BOOST strategy was more complicated to implement and involved the need for throttle operation. Initially the concepts were evaluated in an in-house model and AVL Boost® (AVL List Gmbh, Graz, Austria), and proved feasible. Then, a BMW K75 engine was altered and tested on a brake dynamometer. The running engine proved the initial concept, by improving the efficiency for the ECO condition in almost 40% in relation to the stock engine and getting well over the required BOOST power, getting to 35 kW, while keeping an efficiency similar to the stock engine at the wide open throttle (WOT). In order to protect the engine during BOOST, the mixture was enriched, while at ECO the mixture was leaned to further improve efficiency. The fixed operation configuration allows the reduction, not only of complexity and cost of the RE, but also the set point optimization for the engine and generator. When integrated as a RE into a typical European light duty vehicle, it provided a breakthrough consumption reduction relatively to existing plug-in hybrid electric vehicles (PHEVs) in the market in the charge sustaining mode. The very high efficiency of the power generation seems to compensate for the loss of efficiency due to the excess electricity production, which must be stored in the battery. The results indicate that indeed it is possible to have an efficient solution, in-line with the electric mobility sustainability paradigm, which can solve most of the shortcomings of current EVs, notably those associated with batteries (range, cost and charging time) in a sustainable way.

Objectives This study aims to correlate patient-reported reactions with in vitro analyses of the pH, abrasive quality, and cytotoxicity of four toothpastes. Materials and Methods One hundred twenty-one patients received non-identified samples of toothpaste to be used for 6 days and answered a questionnaire about their sensations. In vitro analysis: the pH of toothpastes was measured with a pH meter. The abrasivity of toothpastes was evaluated against composite resin specimens ( n  = 10). A toothbrushing machine was used to simulate wear, which was indirectly measured by mass loss using a scale. Cell culture media conditioned with toothpaste were used to assess the cytotoxicity. Confluent cells were kept in contact with the conditioned media or control for 24 h. The cell viability was measured using the 3-(bromide, 4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium (MTT)-reduction assay. The obtained data on the pH, weight loss, and cell viability were compared by ANOVA/Tukey’s tests ( p  < 0.05). Results With the exception of the bleaching effect paste, the Oral B® paste produced the highest frequencies of irritation reports, tooth sensitivity, taste discomfort, and texture discomfort in the clinical study; patients also reported rougher teeth, soft tissue peeling, dry mouth, thrush, tingling, and taste changes in response to this paste. The in vitro analysis demonstrated that Oral B® had the lowest pH, the highest abrasivity, and produced the lowest cell viability ( p  < 0.01). Conclusion Results suggest that low pH toothpastes that are highly abrasive and cytotoxic may cause undesirable reactions in patients. Clinical relevance Toothpaste’s properties should be well known for indication to patient therefore minimizing discomfort reports.

The present paper addresses the use of surfaces structured with arrays of square micro-cavities to enhance pool boiling heat transfer. The heat transfer performance, obtained with the structured surfaces is evaluated based on the measured boiling curves and on the heat transfer coefficients. Two new parameters are suggested to relate the bubble dynamics (and consequently the surface topography) with the heat transfer coefficients: the modified dimensionless cavity spacing and the dimensionless distance, which cover the governing parameters of the phenomena. Correlations of these parameters with the heat transfer coefficients allowed to identify the best performing patterns, from those tested so far. Based on this progress it is expected that optimization of these relations will lead to precise relations which allow a systematic optimization of the surface pattern leading to an effective heat transfer enhancement, for situations involving high heat fluxes.

We study the scattering modes of light in a three-dimensional disordered medium, in the scalar approximation and above the critical density for Anderson localization. Localized modes represent a minority of the total number of modes, even well above the threshold density, whereas spatially extended subradiant modes predominate. For specific energy ranges however, almost all modes are localized, yet adjusting accordingly the probe frequency does not allow to address these only in the regime accessible numerically. Finally, their lifetime is observed to be dominated by finite-size effects, and more specifically by the ratio of the localization length to their distance to the system boundaries.

The horizontally assembled circular microchannel (Dh= 543μm, LHT = 60mm) made of transparent borosilicate glass is kept under constant wall heat flux conditions by means of a transparent metallic thin film deposit at the channel external wall as in Silvério and Moreira [1]. Heat transfer and pressure drop measurements are achieved by measuring the temperature and pressure at the channel inlet and outlet. Temperature is also measured along the channel outer wall. Experiments are carried with two different fluids, ethanol and methanol. Inlet liquid subcooling is of 297K, mass fluxes, G, up to 689kg.m−2.s−1 and imposed heat fluxes, q\"s, up to 12.5W.cm−2 at ΔTsub from 0.8 to 50K. Synchronized high-speed visualization and microscope optics are used to determine dominant two-phase flow patterns and characterize hydrodynamic instabilities. Vapor qualities, χ, of −0.1 (indicating a subcooled liquid state) to 0.5 are under investigation. Semi-periodic variation of the flow patterns is noticeable for different flow conditions.

ObjectiveThe study evaluated the longevity, effectiveness, safety, and impact on the oral health-related quality of life of in-office dental bleaching using low-concentration hydrogen peroxides.Materials and methodsRandomized, parallel, and double-blinded clinical trial was performed with 54 participants using 6% or 15% hydrogen peroxide (HP) in-office bleaching activated via hybrid LED/laser light. Tooth color was evaluated at baseline (T1), 1 week of bleaching (T2), 2 weeks of bleaching (T3) and 1 week (T4) and 6 months (T5) after finishing the bleaching using the Classical Vita™ scale and spectrophotometer. Tooth sensitivity and gingival irritation were measured with Visual Numeric Scale and Modified Gingival Index. The impact on quality of life was evaluated using the Oral Impact on Daily Performance. The data were analyzed using the Friedman, Mann-Whitney, and McNemar tests (p < 0.05).ResultsThe group HP15% presented significant color change (ΔE) from T1 to T4 (p = 0.002) and T1 to T5 (p < 0.001). Parameters L, a*, and b* differed significantly at T3, T4, and T5 compared T1 for both groups. At 6-month follow-up, 57.1% of HP6 and 43.7% of HP15% participants migrated from B1 to a darker color. No significant differences were observed between the groups in tooth sensitivity, gingival irritation, or impact on quality of life.ConclusionsBoth agents showed bleaching effectiveness, but HP15% presented greater color stability than HP6%, at 6-month follow-up. The agents showed low levels of tooth sensitivity, gingival irritation, and did not affect the oral health-related quality of life of the participants.Clinical relevanceDespite the greater presence of sensitivity during treatment compared with 6% hydrogen peroxide, 15% hydrogen peroxide demonstrated better bleaching effectiveness, and greater color stability at the end of bleaching and at 6-month follow-up. The use of 15% hydrogen peroxide presents more suitable results.

This paper addresses part of a wider project aiming at the development of a microchannel based heat sink to cool photovoltaic panels. The work presented here gives emphasis to working conditions leading to flow boiling in a microchannel and focuses on flow instabilities and on the potential effect of surface microstructuring in heat transfer enhancement and in controlling such instabilities. After identifying the flow boiling regimes, the observed phenomena are qualitatively and quantitatively described. The results show that a regular pattern of microcavities on the surface to cool enhances heat transfer and promotes the occurrence of a more stable flow.

Dipole-dipole interactions are at the origin of long-lived collective atomic states, often called subradiant, which are explored for their potential use in novel photonic devices or in quantum protocols. Here, we study subradiance beyond linear optics and experimentally demonstrate a two hundred-fold increase in the population of these modes, as the saturation parameter of the driving field is increased. We attribute this enhancement to a mechanism similar to optical pumping through the well-coupled superradiant states. The lifetimes are unaffected by the pump strength, as the system is ultimately driven toward the single-excitation sector.

This paper proposes a detailed analysis of bubble dynamics to describe pool boiling heat transfer in extreme wetting scenarios (superhydrophobic vs hydrophilic). A mechanistic approach, based on extensive post-processing allows quantifying the relative advantage of the superhydrophobic surfaces to endorse the onset of boiling at very low superheats (1-2K) vs their worse heat transfer performance associated to the swift formation of an insulating vapour film. Based on this analysis, a simple biphilic surface is created. The results suggest that for high heat fluxes, bubble dynamics is dominated by the emission of very small bubbles, which seems to affect the interaction mechanisms, precluding the emission of the large bubbles from the surface, thus compromising the good performance of the biphilic surfaces.