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In the last decade, Science Education has played a crucial role in the training of young students, supporting them in understanding the world around us, making them active citizens, responsible and capable of innovation in a knowledge-based society (Recommendation of the European Parliament and of the Council, 18 December 2006). The purpose of the presented experimental research, carried out in a fifth class of a Primary School in Treviso (Italy), was to test the validity of a teaching approach based on the scientific method, in particular on the observation-comparative method (characteristic of Evolutionary Biology), in the teaching of Life Sciences. The research focused on the planning and realization of a learning unit for the study of the human musculoskeletal system, made by a theoretical initial phase followed by a practical approach, which involved the comparison of anatomical structures of three vertebrates: trout, chicken and pig. The experimental work was preceded by a survey on didactics, aimed to identify methods and teaching practices adopted by teachers of Natural and Experimental Sciences of the Primary School, especially for the Biology and in particular for the musculoskeletal system. For example, from this preliminary investigation it was found that the teachers of the Primary School do not use tools such as the stereoscope for viewing biological material, despite they claim to take an active approach for the teaching of Science and they have the appropriate scientific instruments. The results have shown that despite the traditional teaching proposes the dissection of foot from chicken, an animal belonging to the class of birds, pig is the most suitable for the specific practical experimental teaching, because is a mammal and thus is more similar to human from the morphological point of view, as well as the phylogenetic relationships. Active teaching and direct observation of animal structures reinforced the concepts theoretically exposed. It was also confirmed the high teaching potential of the integration of macroscopic and microscopic observations. The observational-comparative method is a key component for the study of the Biology; for this reason all the topics linked to the study of the human body can be addressed through the use of this active methodology. This kind of approach can motivate students, making them active participants in their own learning. The most innovative aspect of the proposed experimental program is the comparison of the musculoskeletal system in three selected vertebrates. Although the Italian Guidelines for the Curriculum in the Primary School emphasize the importance of scientific comparison between animals and human, with the objective of learning at the end of the fifth class to continue the study of the functions of organisms and compare the reproduction of human, animals and plant, it is also true that the comparison should be also made between animals that do not include human, in particular for the systems important from the physiological point of view.

Per- and polyfluoroalkyl substances (PFASs) have multiple emission sources, from industrial to domestic, and their high persistence and mobility help them to spread in all the networks of watercourses. Diffuse pollution of these compounds can be potentially mitigated by the application of green infrastructures, which are a pillar of the EU Green Deal. In this context, a phytoremediation pilot plant was realised and supplied by a contaminated well-located in Lonigo (Veneto Region, Italy) where surface and groundwaters were significantly impacted by perfluoroalkyl acids (PFAAs) discharges from a fluorochemical factory. The investigation involved the detection of perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), perfluorobutanesulfonic acid (PFBS) and perfluorooctanesulfonic acid (PFOS) inside the inlet and outlet waters of the phytoremediation pilot plant as well as in reed grasses grown into its main tank. The obtained results demonstrate that the pilot plant is able to reduce up to 50% of considered PFAAs in terms of mass flow without an evident dependence on physico-chemical characteristics of these contaminants. Moreover, PFAAs were found in the exposed reed grasses at concentrations up to 13 ng g−1 ww. A positive correlation between PFAA concentration in plants and exposure time was also observed. In conclusion, this paper highlights the potential efficiency of phytodepuration in PFAS removal and recommends improving the knowledge about its application in constructed wetlands as a highly sustainable choice in wastewater remediation.

Per-and poly-fluorinated alkyl substances (PFAS) are a group of chemicals used in a wide variety of commercial products and industrial applications. These chemicals are persistent, can accumulate in humans' and animals' tissues and in the environment, representing an increasing concern due to their moderate to highly toxicity. Their global distribution, persistence and toxicity led to an urgent need to investigate bioaccumulation also in marine species. In 2013 PFAS contamination was detected in a vast area in Veneto region, mainly in Adige and Brenta rivers. In order to investigate any relevant presence of these substances in marine vertebrates constantly living in the area, PFAS were measured in hepatic tissue samples of 20 bottlenose dolphins (Tursiops truncatus) stranded along the northern Adriatic Sea coastline between 2008 and 2020. Using high performance liquid chromatography-mass spectrometry, 17 target PFAS (PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTrDA, PFTeDA, PFBS, PFHxS, PFOS, PFDS, PFHpS, PFPeS), were quantified in the samples. PFAS profiles were generally composed of the same five dominant PFAS (PFOS > PFUnA > PFDA ≈ PFDoA ≈ PFTrDA). The greatest PFOS concentration found was 629,73 ng/g wet weight, and PFOS accounted until 71% in the PFAS profiles. No significant differences between sexes were found, while calves showing higher mean values than adults, possibly indicating an increasing ability in the elimination of PFAS with age. Finally, a temporal analysis was carried out considering three different periods of time, but no temporal differences in concentrations were found. The results suggest that long-chain PFAS are widespread in bottlenose dolphins along the North Adriatic Sea. Furthermore, they represent a baseline to investigate the impact of PFAS on marine mammals’ conservation and health. Filling an important gap in the knowledge of PFAS accumulation in bottlenose dolphins, this study highlights the relevant role of Environmental and Tissue Banks for retrospective analyses on emergent contaminants.

This study falls into the field research of Life Science didactics. According to the main Italian (Italian Guidelines for the Curriculum in the Primary School - 2012 Edition) and European law documents (Recommendation of the European Parliament and of the Council, 18 December 2006), and to the scientific research made on the subject, the most effective approach to Live Science teaching seems to be the one that uses laboratory didactics, allowing the student to be active protagonists of their learning. This work focuses on laboratory didactics and how they, integrated with the traditional teaching methods, could be more valid than the traditional method alone. The subject chosen was Microbiology, in particular microorganisms that interact with food (bacteria that could be beneficial of not for human health and yeasts that could transform food). In order to try this method, a preliminary investigation was carried out regarding the teaching methods usually adopted by teachers of Natural and Experimental Sciences of the Primary School involved in this research. The obtained results were useful to understand the methods used by the teachers and if the teaching of Microbiology was common. As it turned out, Microbiology and the subject of microorganisms in the alimentation is marginally considered in Primary School and this confirmed the originality of the project. The project was divided into two teaching phases. The first one regarded the bacteria and the importance of hand-washing before eating, the second one regarded yeasts and how the alcoholic fermentation could lead to processes like the leavening of bread. In both cases part of the activity was held in the classroom as frontal lesson, and part was in the laboratory, where students (children of the third class of primary school, approximately 8 years old) had the opportunity to work with optical microscopes, culture mediums in Petri’s capsules and with the application of the scientific method. Some simple tests were proposed after each activity, in order to verify and compare the efficacy of the two types of didactics. The results confirmed the initial hypothesis that, in the teaching-learning of Life Sciences, using laboratory didactics is more effective than a traditional approach. The scientific method, used in the experimentation, was very valid for a meaningful learning, and it produced skills that may also be used in other contexts. The use of scientific instruments, such as optical microscope, and techniques, such as microbial culture, gave value to the application of scientific method and kept the students very motivated and interested in the subject of Microbiology. All these activities can be proposed again to other students of primary and secondary school with some adaptations.

A method for the determination of 12 perfluoroalkyl acids (PFAA) in vegetal samples was proposed. The analytical procedure was developed to optimize the detection of short-chain PFAA (C < 8) due to their higher potential to be translocated and bioaccumulated in plants than long-chain congeners. The method, based on ultrasonic extraction, clean-up and HPLC-MS/MS analysis, determined PFAA in different plant tissues allowing the PFAA distribution and partition in vegetal compartments to be studied. The performance of this analytical procedure was validated by analysing samples (root, stem and leaf) of reed grass. The validated method was then applied to graminaceous plants from an agricultural area impacted by a fluorochemical plant discharge (Northern Italy). The PFAA congeners were detected in most of the samples with sigma PFAA concentrations in the whole plant ranging from

Recent studies describe the use of UAVs in collecting blow samples from large whales to analyze the microbial and viral community in exhaled air. Unfortunately, attempts to collect blow from small cetaceans have not been successful due to their swimming and diving behavior. In order to overcome these limitations, in this study we investigated the application of a specific sampling tool attached to a UAV to analyze the blow from small cetaceans and their respiratory microbiome. Preliminary trials to set up the sampling tool were conducted on a group of 6 bottlenose dolphins (Tursiops truncatus) under human care, housed at Acquario di Genova, with approximately 1 meter distance between the blowing animal and the tool to obtain suitable samples. The same sampling kit, suspended via a 2 meter rope assembled on a waterproof UAV, flying 3 meters above the animals, was used to sample the blows of 5 wild bottlenose dolphins in the Gulf of Ambracia (Greece) and a sperm whale (Physeter macrocephalus) in the southern Tyrrhenian Sea (Italy), to investigate whether this experimental assembly also works for large whale sampling. In order to distinguish between blow-associated microbes and seawater microbes, we pooled 5 seawater samples from the same area where blow samples' collection were carried out. The the respiratory microbiota was assessed by using the V3-V4 region of the 16S rRNA gene via Illumina Amplicon Sequencing. The pooled water samples contained more bacterial taxa than the blow samples of both wild animals and the sequenced dolphin maintained under human care. The composition of the bacterial community differed between the water samples and between the blow samples of wild cetaceans and that under human care, but these differences may have been mediated by different microbial communities between seawater and aquarium water. The sperm whale's respiratory microbiome was more similar to the results obtained from wild bottlenose dolphins. Although the number of samples used in this study was limited and sampling and analyses were impaired by several limitations, the results are rather encouraging, as shown by the evident microbial differences between seawater and blow samples, confirmed also by the meta-analysis carried out comparing our results with those obtained in previous studies. Collecting exhaled air from small cetaceans using drones is a challenging process, both logistically and technically. The success in obtaining samples from small cetacean blow in this study in comparison to previous studies is likely due to the distance the sampling kit is suspended from the drone, which reduced the likelihood that the turbulence of the drone propeller interfered with successfully sampling blow, suggested as a factor leading to poor success in previous studies.

With a view to the active learning, that makes the students protagonist, responsible and aware of the learning process, the present study presents an experimental work designed to demonstrate the usefulness and the validity of the scientific method as the basic element of the teaching of Life Sciences. Scientific training adopts an inductive approach to knowledge that allows us to observe, imagine, discover, verify, generalize, providing the tools needed to understand the reality. This research focused on the study of seasonality in the first class of a Primary School in Treviso (Italy), using a teaching approach based on direct field exploration and planning activities in which the sensory perceptual aspect is only the starting point. Those activities were based on both the observational comparative method (characteristic of Evolutionary Biology), and the experimental method (a feature of Functional Biology). Prior to the experimental out a preliminary investigation work was carried, involving the teachers of Natural Sciences and Experimental of some Italian Primary Schools. This survey allowed to paint a partial picture of how it the teaching of the Biology is performed, with particular reference to the seasonality, which was the starting point to develop and test a didactic approach of adequate originality. The addressed topics were divided in four stages corresponding to the seasons, and covered aspects of plant morphology (leafs, vascular tissues, flowers, fruits), plant physiology (the color changes of the leafs, leaf abscission, plant nutrition, fruit development) and the concept of biodiversity. The obtained results showed that, using the scientific method and laboratory tools such as the stereoscope and the optical microscope, conceptualizations planned for second cycle of the Primary School can be met with success in the first class, helping to reach the programmed goals optimally and often excellently, facilitating the achievement of competences such as the use of a correct scientific nomenclature. With this approach, the young students were motivated, stimulated, intrigued, and this potentially provides a meaningful, authentic and transferable Lifelong Learning and the development of a scientific culture together with an early interest in the Sciences.

As part of the design validation of components mounted on rotating machinery such as a car engine, it is essential to understand the environmental stress in which they operate. In the case of vibration loadings, the reliability must be verified according to accelerated tests that realistically reproduce the in-service stress. Indeed, a representative validation profile permits not only the assessment of the component durability, but also provides a reliable reference for design optimization (downsizing), reducing development cycle costs, and time scale. This paper proposes an innovative methodology to generate tailored vibration signals more representative of the real environment. First, the severity of the test is tailored to the specific engine usage profile, i.e., the time spent at each revolution per minute (RPM) for a given percentile of customer usage. Traditional signals of Power Spectrum Density (PSD) and sine sweep are developed according a fatigue damage approach (test tailoring). Then, a more representative vibration specification is obtained as a multiple-sine-on-random signal. The signal is expressed as a series of multiple sine sweeps (representing the engine harmonics) and a PSD (representing the random leftover signal). A case study applied to an engine mounted heat exchanger (a water-cooled intercooler) is presented. The generated specification is compared to the validation signals developed according to existing procedures. The results show that 1) the tailored approach decreases the risk of unnecessary over-testing and 2) the multi-swept-sine-on-random signal guarantees the best representativeness of the real environment.

The patterning of silicon surfaces by organic molecules emerges as an original way to fabricate innovative nanoelectronic devices. In this regard, we have studied how a diamine, N,N,N',N'-tetramethylethylenediamine (TMEDA, (CH3)2N-[CH2]2-N(CH3)2), chelates the silicon dimers of the Si(001)-2 × 1 surface. Starting from very low coverage to surface saturation (at 300 K), we used real-time scanning tunneling microscopy (STM) in a scanning-while-dosing approach. The images show that the molecules can adopt two bonding configurations: the cross-trench (CT) configuration by bridging two adjacent dimer rows, and the end-bridge (EB) configuration by chelating two adjacent dimers in the same row. However, while CT dominates over EB at low coverage, the percentage of EB adducts steadily increases, until it becomes largely dominant at high molecular coverage. Above a critical coverage θmol of ∼0.13 monolayer (ML), a sudden change in the molecular imprints is seen, likely due to a change in the tunneling conditions. The EB stapling of two adjacent dimers in a row via a dual-dative bond (as shown by XPS) is achieved efficiently by the TMEDA molecule with a very high chemical selectivity. The EB is a unique configuration in amine adsorption chemistry, as it leads to the formation of a pair of first-neighbor, doubly-occupied dangling bonds. Further reactivity of the EB site with other molecules remains to be explored, and possible reaction schemes are envisaged.

One of the strategies aimed at improving the reliability of new or existing components is the reduction of the variability of the product strength. From a manufacturing point of view, a well-controlled process diminishes the variability of the product resistance facing in-service stress, therefore reducing the area of the stress-strength interference region (probability of failure).

Summary & ConclusionsThe development of an engine-cooling module (ECM) for an European carmaker faced a major blocking point. The stalemate concerned the design of the suspension rubbers separating the engine-cooling radiator (the ECM carrier) from the chassis. The development of an engine-cooling module (ECM) for an European carmaker faced a major blocking point. The stalemate concerned the design of the suspension rubbers separating the engine-cooling radiator (the ECM carrier) from the chassis. From the one hand, the damping rubbers had to be soft, in order to be compliant with noise, vibration & harshness (NVH) criteria – acoustic noise and vibration transmitted to the cabin. On the other hand, their softness would provoke such high amplitude response during shaker tests that the module carrier (the radiator) would fail at the early stage of vibration testing – a leakage was observed after 10 hours of the targeted 90 hours duration. New rubbers, designed for durability purposes, would fail to meet the NVH criteria. The project development team went through a double-faced dilemma: how to design rubbers with an acceptable trade-off between NVH and durability of the engine-cooling radiator, and how to find a quick and efficient way to validate the design in order to be compliant with vibration validation tests. Together with the customer, our company (automotive tier-1 supplier) established an iterative design optimization of the damping rubbers, based on the simultaneous feedback from the acoustic response and the durability predictions. The goal was to develop a strategy permitting a quick an effective criteria for damage estimation for each design proposed.

Short-chain perfluoroalkyl acids (PFAAs) have shown a high potential for plant (crop) uptake, making them possibly significant contributors to the total dietary exposure to PFAAs. The plant uptake of PFAAs is a complex process that needs better characterization, as it does not only depend on perfluoroalkyl chain length, but also on their polar terminal group, on the plant species and the exposure media. Here, a plant uptake study with nine perfluoroalkyl acids (PFAAs) was carried out under the hydroponic (soilless) exposure conditions. Red chicory was grown in a nutrient solution, spiked with PFAAs mixture at three different concentrations (i.e. 62.5, 125 and 250 mu g/L), in order to extend the range of levels tested and reported in the literature so far. Bioaccumulation metrics and transpiration stream concentration factors (TSCFs) were employed for the plant uptake characterization and consequent comparison with the results of soil uptake experiment we previously performed with the same crop. The results showed that calculated root concentration factors (RCFs) increase with PFAA chain length, while the opposite chain length dependence was present for shoots. Plants from two treatments with the highest PFAAs concentrations manifested physiological changes (discoloration, inhibited roots and leaves growth), despite of the used exposure concentrations beingmuch lower than previously published phytotoxicity thresholds. A comparison among RCFs and TSCFs derived from hydroponic and from the soil experiment has emphasized their different magnitudes and PFAAs chain length dependence patterns. They could not be ascribed only to soil sorption as a process decreasing PFAAs bioavailability for plants, but also to developmental differences between the root systems formed in soil and in nutrient solution and to the potential competitive PFAAs sorption to roots in hydroponics. The interchangeable use of bioaccumulation and translocation parameters derived in hydroponic and soil systems would lead to erroneous conclusions and plant uptake predictions. (C) 2020 Elsevier B.V. All rights reserved.

There is growing concern for the wide use of perfluorooctanoic acid (PFOA) because of its toxic effects on the environment and on human health. A new compound – the so called C6O4 (perfluoro ([5-methoxy-1,3-dioxolan-4-yl]oxy) acetic acid) - was recently introduced as one of the alternative to traditional PFOA, however this was done without any scientific evidence of the effects of C6O4 when dispersed into the environment. Recently, the Regional Agency for the Protection of the Environment of Veneto (Italy) detected high levels of C6O4 in groundwater and in the Po river, increasing the alarm for the potential effects of this chemical into the natural environment. The present study investigates for the first time the effects of C6O4 on the Manila clam Ruditapes philippinarum exposed to environmental realistic concentrations of C6O4 (0.1 µg/L and 1 µg/L) for 7 and 21 days. Furthermore, in order to better understand if C6O4 is a valid and less hazardous alternative to its substitute, microbial and transcriptomic alterations were also investigated in clams exposed to 1 µg/L of PFOA. Results indicate that C6O4 may cause significant perturbations to the digestive gland microbiota, likely determining the impairment of host physiological homeostasis. Despite chemical analyses suggest a 5 times lower accumulation potential of C604 as compared to PFOA in clam soft tissues, transcriptional analyses reveal several alterations of gene expression profile. A large part of the altered pathways, including immune response, apoptosis regulation, nervous system development, lipid metabolism and cell membrane is the same in C6O4 and PFOA exposed clams. In addition, clams exposed to C6O4 showed dose-dependent responses as well as possible narcotic or neurotoxic effects and reduced activation of genes involved in xenobiotic metabolism. Overall, the present study suggests that the potential risks for marine organism following environmental contamination are not reduced by replacing PFOA with C6O4. In addition, the detection of both C6O4 and PFOA into tissues of clams inhabiting the Lagoon of Venice - where there are no point sources of either compounds - recommends a similar capacity to spread throughout the environment. These results prompt the urgent need to re-evaluate the use of C6O4 as it may represent not only an environmental hazard but also a potential risk for human health.

[This corrects the article DOI: 10.1371/journal.pone.0235537.].

Due to their unique properties, perfluorinated substances (PFAS) are widely used in multiple industrial and commercial applications, but they are toxic for animals, humans included. This review presents some available data on the PFAS environmental distribution in the world, and in particular in Europe and in the Veneto region of Italy, where it has become a serious problem for human health. The consumption of contaminated food and drinking water is considered one of the major source of exposure for humans. Worldwide epidemiological studies report the negative effects that PFAS have on human health, due to environmental pollution, including infertility, steroid hormone perturbation, thyroid, liver and kidney disorders, and metabolic disfunctions. In vitro and in vivo researches correlated PFAS exposure to oxidative stress effects (in mammals as well as in other vertebrates of human interest), produced by a PFAS-induced increase of reactive oxygen species formation. The cellular antioxidant defense system is activated by PFAS, but it is only partially able to avoid the oxidative damage to biomolecules.

The retia mirabilia are vascular nets composed of small vessels dispersed among numerous veins, allowing blood storage, regulation of flow and pressure damping effects. Here, we investigated their potential role during the diving phase of the bottlenose dolphin (Tursiops truncatus). To this effect, the whole vertebral retia mirabilia of a series of dolphins were removed during post-mortem analysis and examined to assess vessel diameters, and estimate vascular volume and flow rate. We formulated a new hemodynamic model to help clarify vascular dynamics throughout the diving phase, based on the total blood volume of a bottlenose dolphin, and using data available about the perfusion of the main organs and body systems. We computed the minimum blood perfusion necessary to the internal organs, and the stroke volume and cardiac output during the surface state. We then simulated breath-holding conditions and perfusion of the internal organs under the diving-induced bradycardia and reduction of stroke volume and cardiac output, using 10 beats min−1 as the limit for the heart rate for an extended dive of over 3 min. Within these simulated conditions, the retia mirabilia play a vital role as reservoirs of oxygenated blood that permit functional performances and survival of the heart and brain. Our theoretical model, based on the actual blood capacity of the retia mirabilia and available data on organ perfusion, considers the dynamic trend of vasoconstriction during the diving phase and may represent a baseline for future studies on the diving physiology of dolphins and especially for the blood supply to their brain.

The retia mirabilia are vascular nets composed of small vessels dispersed among numerous veins, allowing blood storage, regulation of flow and pressure damping effects. Here, we investigated their potential role during the diving phase of the bottlenose dolphin (

This study focuses on the short groundwater residence time induced by the development of a dense rooting system in a forested area employed as a buffer zone planned for nitrogen removal. The buffer zone consists of a rectangular area of 0·7 ha sub-irrigated by two ditches and drained by an outflow ditch lying in the centre of the area. The pristine soil (silty clay loam) was characterized by a low hydraulic conductivity, but the agricultural practice first, and then the rooting system increased the permeability of the top soil. This was confirmed by the elevated discharge in the outflow ditch and by the elevated hydraulic conductivity values determined via slug tests. The groundwater residence time was monitored, once the rooting system was completely developed, via Rhodamine-WT injection in the inflow ditch. The breakthrough curves were simulated using a one-dimensional analytical model (CXTFIT) to calculate the residence time. In addition, a three-dimensional flow and transport model (MODFLOW and MT3DMS) was calibrated using piezometric heads, groundwater fluxes and Rhodamine-WT concentrations. The CXTFIT model overestimated the dispersivity and underestimated velocity respect to MT3DMS. This study shows that residence time can decrease respect to the value expected from the hydraulic conductivities of the pristine soils and that one-dimensional analytical models can give a false impression compared with soil parameters respect to three-dimensional flow and transport models. Given the importance of the residence time for biological processes in buffer zones, a greater effort is needed to improve measurement techniques on subsurface flow's heterogeneity. Copyright © 2013 John Wiley & Sons, Ltd.

The high level of competitiveness of the automotive industry requires the capability to predict in-service durability during multiple stages of product development: initial design phase, design modification and/or optimization, change of materials (metals, plastics and polymers) or suppliers, use of new testing facilities, etc. Some commonly known methods and tools are often applied for reliability purposes. This includes in particular: i) the acquisition and analysis of road load data (mechanical or climatic stresses), ii) the use of accelerated bench tests, iii) the measurements of the local deformation using strain sensors, and iv) structural simulations. Whereas in the past these methods were used separately, the novelty of this paper is that both commonly applied and innovative tools are used in synergy to predict and improve the reliability of automotive components and merged into a Synergetic Design for Reliability (SRD). A case study that investigates the reliability of an intercooler (charge air cooler) undergoing pressure pulsation fatigue loadings is here presented. Starting from in-service road load data, a design of experiments (DOE) approach is applied to the identification the main factors that influence the fatigue life of the component. Measurements during bench tests are then used to ameliorate the existing validation specification, and to correlate the results from structural simulation.

The drastic reduction in pollutants emission that has followed recent international regulations imposes that engine fuel consumption be optimized as ever. Efficient engine cooling components together with an improved thermal management strategy play an important role in increasing engine performance, resulting in reduced fuel consumption and decreased pollution emissions. At the same time, new market trends are imposing longer warranty commitments, therefore challenging the capability of automotive suppliers to design products capable of high performance and extended reliability. In this framework, the reliability of engine cooling modules is a real economical and technical topic which has to be validated according to a rigorous methodology. By avoiding the over-use of standard and generic specifications (which cause over or under testing of the component during development phase), this paper proposes the so-called “test tailoring approach.” The goal is to validate the mechanical endurance of our products according to accelerated durability tests that are the most representative as possible to the environmental stresses that the components expect to see during their in-service life. This method permits the generation of customized accelerated bench tests, based on real measurements taken on the vehicle during field tests. The use of safety coefficients and Weibull analysis of destructive tests allows ensuring that the reliability targets are reached. These tailored specifications are employed to validate the mechanical endurance of the engine cooling module undergoing vibration, pressure pulsation and thermal shock stress loadings. This paper presents how this holistic philosophy has been used to validate the design of a new generation of heat exchangers (CO 2 gas cooler and evaporator).

The world distribution of dwarf and pygmy sperm whales (Cetacea: Kogiidae) [Kogia spp.] is poorly known, and derived mostly from records of stranded animals. At sea, both species are elusive and difficult to identify. We photo-documented the presence of dwarf sperm whale (Kogia sima) in the waters of the Union of the Comoros. All three occurrences were sightings of apparently healthy animals from 2011 to 2013 in and near Itsandra Bay, off the island of Grande Comore. We discuss the importance of the Mozambique Channel and the Agulhas Current Large Marine Ecosystem for the species in the Western Indian Ocean.

Vibration qualification tests are currently indispensable for vehicle manufacturers and their suppliers. Carmakers' specifications are therefore conceived to challenge the mechanical endurance of car components face to numerous in-service detrimental phenomena: fatigue damage, shocks or accidents, and mechanical degradation. The vibration signals used in the automotive industry are of various types (random, harmonic, shock pulses) and are becoming more and more complex (multi-random, swept-sine-on-random etc.), covering different frequency ranges. With automotive business requiring new product development to be faster, a robust methodology that permits to easily compare and quantify the severity of a vibration specification would be advantageous from a design of reliability perspective. The objective of this paper is to illustrate a set of tools that can be applied to the comparison of vibration specification signals used to validate the mechanical endurance of car components undergoing stressing vibration loadings. The paper will describe different criteria and new innovative methodologies adopted to perform the required comparison, from quick and effective specification analysis, to even more complex purposes (for example when building a new generic vibration signal for early product development). Following a brief theoretical introduction, several case studies will show practical applications of the methodology.

This study illustrates a methodology used in our company (car components manufacturer) which enables to generate, starting from any given customer vibration specification, a fatigue damage equivalent Power Spectrum Density (PSD) signal. This PSD can be used to evaluate the mechanical durability of engine cooling or engine-mounted components. The methodology permits to accelerate durability bench tests, to compare the severity of different vibration specifications and to perform structural simulation. One practical example will illustrate the experimental validation of the procedure, based on strain-damage measurements. The main limitations of the methodology are related to the nature of the specified signal. In the case of specifications composed of purely random signals, the method is always applicable.

Observed variations in dolphin acoustic signals may be associated with behavior, social composition, and local differences in habitat features. This study aims at characterizing whistles emitted by the spinner dolphin population occurring in the waters of the main island of the Archipelago of Comoros (Mozambique Channel, Indian Ocean) and to assess factors possibly influencing the acoustic structure of signals. All parameters examined on 953 whistles significantly differed in relation to environmental conditions, group size, and behavior. By mixed model analysis, it was found that only habitat characteristics play a role in the variation of frequency parameters, and exerted on the acoustic structure of whistles stronger influence than socio-behavioral factors. Spinner dolphins occurring in the Comoros archipelago use higher frequencies and show longer signal duration compared to those from the Pacific and the Atlantic. Results suggest that frequency parameters are distinctive of the local population and reflect the habitat use of the species in the area. In conclusion, acoustic measurements may be crucial elements to be included in monitoring programs to identify local peculiarities of dolphins' populations.

The importance of specification definition in the embedded-software design flow has been proven over the years. The entire design process relies on the specification quality, which inevitably depends on designer knowledge and skills. Automatic property mining is part of the efforts proposed to make this activity easier for the designers. Nonetheless, the existing approaches are limited to the detection of either arithmetic invariants of programs or temporal properties for Boolean designs, e.g., bit-level hardware descriptions. In this work, we present a dynamic mining approach able to infer linear temporal logic (LTL) properties for embedded software. The mined properties are in the form of temporal relationships between arithmetic expressions. The approach considers the execution traces only, thus it is completely independent from the code implementation. Experimental results demonstrate the effectiveness of the approach.

Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003–2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g. each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion.

The reaction of n-propyltriethoxysilane (PTES) with clean Si(001)-2 × 1 at room temperature is studied by synchrotron radiation X-ray photoemission spectroscopy (XPS). It is shown that PTES dissoci...

TiO2 anatase nanotubes synthesised via anodic oxidation were used as adsorbent for the uptake of U and Pb from aqueous solution and the photoremoval of As(III). An X-ray photoelectron spectroscopy study of the sorbent medium surface revealed a high adsorption of U and Pb at pH 8. The adsorption of the uranyl ion was enhanced in an anoxy (N2) atmosphere, because this prevents the formation of very stable carbonyl complexes. As(III) was adsorbed on TiO2 but in the presence of O2 and UV light was oxidized to As(V). XPS analysis revealed that in the pH range 3-9 As(V) was always the major species detected at the surface of the titania photocatalyst.