Autofluorescence (AF) in mosquitoes is currently poorly explored, despite its great potential for investigation of body structures and biological functions. Here, for the first time AF in larval heads of two mosquitoes of key public health importance, Aedes albopictus (Skuse) and Culex pipiens Linnaeus (Diptera: Culicidae), is studied using fluorescence imaging and spectrofluorometry, similar to a label-free histochemical approach. While pre-senting a generally conserved distribution, AF emission signals show differences in their localization both between mouth brushes and antennae of the two species. The blue AF ascribable to resilin is detected in a more extended area at the antennal bases in Cx. pipiens than in Ae. albopictus, suggesting a potential need to support different antennal movements. The AF spectra, larger in Cx. pipiens than in Ae. albopictus, indicate differences in material composition and molecular properties between the two species likely relatable to their biology, including diverse feeding and locomotion behaviors, with implications for vector control.

A ZrB2-based ceramic, containing short Hi-Nicalon SiC fibers, was fabricated with a Mo-impermeable buffer layer sandwiched between bulk and the outermost oxidation resistant ZrB2-MoSi2 layer, in order to prevent inward Mo diffusion and associated fiber degradation reactions. This additional layer consisted of ZrB2 doped with either Si3N4 or with the polymer-derived ceramics (PDCs) SiCN and SiHfBCN. Scanning electron microscopy imaging and elemental mapping via energy-dispersive X-ray spectroscopy showed that this tailored sample geometry provides an effective diffusion barrier to prevent the SiC fibers from deterioration due to reactions with Mo or Mo-compounds. In contrast, the structure of the SiC fibers in a reference sample without buffer layer is strongly degraded by MoSi2 diffusion into the fiber core. The comparison of the three buffer-layer systems showed a moderate alteration of the fiber structure in the case of Si3N4 addition, whereas in the PDC-doped samples hardly any structural change within the fibers was observed. A stepwise reaction mechanism is deduced, based on the continuous progression of a reaction zone that propagates toward the ZrB2-MoSi2 top layer. The progression of such a reaction zone as a consequence of the different eutectic melts forming in the different layers, that is, first in the SiC-fiber-containing bulk, then in the buffer layer itself, and finally in the top layer at high temperature, allows for an effective separation of the ZrB2-MoSi2 top layer from the SiC fibers. Subsequent oxidation at 1500 degrees C and 1650 degrees C for 15 min did not affect the efficiency of all three buffer layers, since no structural changes regarding buffer layer and fibers were observed, as compared to the non-oxidized samples.

Laboratory-synthesized CaCO3 nanoparticles and their nanodispersion in 1,4-butanediol as a working medium have been first characterized and then tested on the surface of Pietraforte stone that forms the cladding of the bell tower of San Lorenzo. Both CaCO3 nanoparticles and their nanodispersion in 1,4-butanediol were characterized in the church in Florence, Italy by X-ray diffraction, thermal analysis, Raman, and Fourier transform infrared spectroscopy, scanning electron microscopy (SEM)/energy-dispersive X-ray (EDX) spectroscopy, and transmission electron microscopy/EDX spectroscopy. The Pietraforte sample surface, before and after CaCO3 nanodispersion treatments, was characterized by comparison of the porosity and specific surface area, capillary absorption, and surface hardness. An ultrastructural morphological investigation by SEM was also carried out, confirming and implementing the effective dynamics of the nanodispersion action. Lastly, differences in stone optical appearance before and after treatment were evaluated by colorimetric measurements. Considering the obtained results of the study, we conclude that CaCO3 nanodispersion in 1,4-butanediol is an effective restorative agent that prevents water infiltration in the stone, reduces stone disruption, and promotes its consolidation without altering its appearance. Finally, the long-lasting stability of the CaCO3 nanodispersion at ambient conditions makes it suitable for production and commercialization.

Photo-assisted Ultrafast Scanning Electron Microscopy (USEM) maps the dynamics of surface photovoltages and local electric fields in semiconducting samples. Photovoltages and their gradients close to surface affect the emission yield and the detection efficiency of secondary electrons (SE), leading to photoexcited SE 2D patterns. In this work, we present a method to characterize the evolution of the patterns up to ultrafast regime. These results reveal the role of surface states in affecting the external field dynamics at picoseconds. Moreover, we show that tiny changes in surface preparation express deeply different photoexcited voltage signals. We investigate the relation between the surface chemistry of Si and photo-induced SE contrast.

Mn dissolution is the main drawback of LiMn2O4 cathodes, leading to capacity fading and anode poisoning. It is well known that improved capacity/cycling performances have been obtained by the Al2O3 coating. It is less clear what is the effect of the coating from the point of view of the fundamental processes occurring within the active material and on the interface with the active material, especially during the first cycle, when a dynamical interaction at a high voltage with an electrolyte and a binder leads to the formation of a passivation layer. We present here the close comparison of coated and uncoated electrodes' X-ray absorption analysis at the interface during the measurements of several charged/discharged states of the electrode. The Al(2)O(3 )coating is significantly effective for stopping the high voltage instability of the battery, especially, when the Mn-O couple reacts with organic species, limiting Mn capture and the electrolyte reaction with the oxide surface. In the low-voltage discharge, on the other hand, more complex structure/electronic modifications occur. The presence of the coating limits disproportionation, preventing a general corrosion with dissolution of the Mn2+ species, and hence improves the electrode performance. From the structural point of view, the signatures of the transformations and a reversible modification of the surface character of the nanoparticles from a spinel to a defective phase are observed, while no charge transfer between the coating and manganese oxide is found. The role of nonthermodynamic interphase formation by means of proton transfer is enhanced for the coated oxide particles.

Metal contacts play a fundamental role in nanoscale devices. In this work, Schottky metal contacts in monolayer molybdenum disulfide (MoS2) field-effect transistors are investigated under electron beam irradiation. It is shown that the exposure of Ti/Au source/drain electrodes to an electron beam reduces the contact resistance and improves the transistor performance. The electron beam conditioning of contacts is permanent, while the irradiation of the channel can produce transient effects. It is demonstrated that irradiation lowers the Schottky barrier at the contacts because of thermally induced atom diffusion and interfacial reactions. The simulation of electron paths in the device reveals that most of the beam energy is absorbed in the metal contacts. The study demonstrates that electron beam irradiation can be effectively used for contact improvement through local annealing.

Early childhood caries (ECC) is a severe manifestation of carious pathology with rapid and disruptive progression. The ECC microbiota includes a wide variety of bacterial species, among which is an anaerobic newly named species, Scardovia wiggsiae, a previously unidentified Bifidobacterium. Our aim was to provide the first ultrastructural characterization of S. wiggsiae and its biofilm by scanning electron microscopy (SEM) using a protocol that faithfully preserved the biofilm architecture and allowed an investigation at very high magnifications (order of nanometers) and with the appropriate resolution. To accomplish this task, we analyzed Streptococcus mutans' biofilm by conventional SEM and VP-SEM protocols, in addition, we developed an original procedure, named OsO4-RR-TA-IL, which avoids dehydration, drying and sputter coating. This innovative protocol allowed high-resolution and high-magnification imaging (from 10000× to 35000×) in high-vacuum and high-voltage conditions. After comparing three methods, we chose OsO4-RR-TA-IL to investigate S. wiggsiae. It appeared as a fusiform elongated bacterium, without surface specialization, arranged in clusters and submerged in a rich biofilm matrix, which showed a well-developed micro-canalicular system. Our results provide the basis for the development of innovative strategies to quantify the effects of different treatments, in order to establish the best option to counteract ECC in pediatric patients.

Filled skutterudites form a wide class of intermetallic compounds thoroughly studied for their promising thermoelectric performance. An electrochemical study was performed on a set of two samples of filled skutterudite with composition Sm-0.1(Fe0.45Ni0.55)(4)Sb-12 differing for the content of additional phases. The aim of the study is to test their resistance to corrosion by a 0.1 M NaCl solution, with particular reference to the effect of the presence of possible extra phases forming during synthesis. Measurements were carried out by electrochemical impedance spectroscopy and potentiodynamic polarization after reaching equilibrium; corrosion products grown on the sample surface after polarization tests were analyzed by scanning electron microscopy. The polarization resistance resulted in increase with the skutterudite amount within the sample, thus pointing at the role of the extra phases (Fe,Ni)Sb-2 and Sb in promoting a localized attack and in accelerating the corrosion rate. This evidence sets a clear indication toward the need for monophasic skutterudites in order to minimize the action of corroding agents in the perspective of optimizing the device durability.

Titanium surface characteristics, including microtopography, chemical composition, and wettability, are essential features to achieve osseointegration of dental implants, but the choice of a particular surface topography is still a debated topic among clinicians. An increased level of implant surface hydrophilicity has been demonstrated to ameliorate osseointegration and shorten healing times. The aim of this work is to develop and test a suitable thermal-based method to enhance titanium surface wettability without modifying other characteristics of the implant surface. For this function, titanium discs with different surface topography have been thermally treated by testing different temperatures and excluding those that led to evident chromatic and morphological modifications. The selected surface gain in wettability after the treatment was assessed through contact angle measurement, chemistry modifications through x-ray photoelectron spectroscopy (XPS) analysis, and microtopography through scanning electron microscopy (SEM). Results showed a great enhancement in hydrophilicity on the tested surfaces without any other modification in terms of surface chemical composition and topography. A possible limitation of this method could be the persistent, although relatively slow, biological aging of the surfaces after the treatment. The present findings indicate that the described treatment could be a safe and effective method to enhance dental titanium hydrophilicity and thus its biological performance.

We describe an analysis system for some of the most important methods of metal welding, based on the acquisition, study and comparison of the atomic emission spectra (in the range from 250 nm to 830 nm), hyperspectral imaging between 600 nm and 950 nm wavelengths and microstructural analysis. The radiometric measurement system acquires information while the welding process is in progress and acquired data are then compared with those resulting from the subsequent microstructural analysis. It is known that the process parameters like, for example, the source power or its speed over the parts during welding, significantly affect the mechanical properties and quality of the resulting junction like hardness, porosity, presence of cracks or other damages and so on. On the other hand, these properties and, above all, the changes in the joint features due to unwanted variations in the process parameters or in the materials being welded, can be inferred by studying the microstructure. In this sense, a proper correlation between the in situ spectral analysis and the microstructural properties is of paramount importance for controlling and adjusting the parameters during the process. In line with the requirements of Industry 4.0, the system described is a study of the application of metrology in a production line, designed to increase information about the production parameters of mechanical industry without increasing costs and limiting the complexity of additional installations. In this paper we report a series of experiments performed using LASER and TIG welding systems applied to different metals. The comparison between the welding conditions acquired by the optical systems and the methods of structural analysis are the basis of a project to improve production systems and their automation.

Additive Manufacturing (AM) can be considered today as a real production technology, which allows to realize parts with a complexity degree that, in some cases, is not achievable otherwise. However, one of the most relevant weak spots is the high surface roughness, especially for metal parts, making necessary the adoption of post-process finishing treatments. This paper deals with the preliminary investigations on the Fluidised Bed Machining (FBM) technology, in which a sample is dipped into a fluidized bed, i.e. a two-phase system where an abrasive, kept in motion through a gas, behaves like a fluid performing a huge number of impacts on the considered surface. This peculiarity could guarantee a high degree of homogeneity of the treated surface morphology. The influence of the impact angle has been investigated by conducting experiments with AlSi10Mg plates made by Selective Laser Melting Technology (SLM), and the fluidized bed operated in bubbling fluidization regime. The treatment has been carried out by dipping the samples for a total time of 3 hours and monitoring the results with a step of 30 min for the first 2 hours. The treated surfaces have been characterized by means of Confocal Microscopy and Scanning Electron Microscopy (SEM). Weight loss measurements have been carried out as well for a preliminary evaluation of wear. Results suggest a poor decrease in surface roughness (S), as also demonstrated by the poor weight loss, both due to a low impact energy of the abrasives. However, variations of other surface texture parameters (S, S, S, R), as well as SEM images, suggest that the main surface-abrasive flow interaction phenomena are micro-ploughing and micro-peening.

This study focuses on several aspects of communication strategies adopted by adults of the Mediterranean flat-headed root-borer Capnodis tenebrionis (Coleoptera: Buprestidae). Morphological studies on the structures involved in mate recognition and acceptance revealed the presence of porous areas in the pronota in both sexes. These areas were variable in shape and size, but proportionally larger in males. The presence of chaetic, basiconic, and coeloconic sensilla in the antennae of both males and females was verified. Bioassays revealed stereotyped rituals in males and the involvement of female pronotal secretions in mate recognition and acceptance. During the mating assays, the female's pronotum was covered by a biologically inert polymeric resin (DenFil (TM)), which prevented males from detecting the secretions and from completing the copulation ritual. The use of the resin allowed for the collection of chemical compounds. GC-MS analysis of the resin suggested it may be used to retain compounds from insect body surfaces and revealed sex-specific chemical profiles in the cuticles. Since adult C. tenebrionis may use volatile organic compounds (VOCs) emitted from leaves or shoots, the VOC emission profiles of apricot trees were characterized. Several volatiles related to plant-insect interactions involving fruit tree species of the Rosaceae family and buprestid beetles were identified. To improve understanding of how VOCs are perceived, candidate soluble olfactory proteins involved in chemoreception (odorant-binding proteins and chemosensory proteins) were identified using tissue and sex-specific RNA-seq data. The implications for chemical identification, physiological and ecological functions in intraspecific communication and insect-host interactions are discussed and potential applications for monitoring presented.

Magnetic scaffolds have recently attracted significant attention in tissue engineering due to the prospect of improving bone tissue formation by conveying soluble factors such as growth factors, hormones, and polypeptides directly to the site of implantation, as well as to the possibility of improving implant fixation and stability. The objective of this study was to compare bone tissue formation in a preclinical rabbit model of critical femoral defect treated either with a hydroxyapatite (HA)/magnetite (90/10 wt %) or pure HA porous scaffolds at 4 and 12 weeks after implantation. The biocompatibility and osteogenic activity of the novel magnetic constructs was assessed with analysis of the amount of newly formed bone tissue and its nanomechanical properties. The osteoconductive properties of the pure HA were confirmed. The HA/magnetite scaffold was able to induce and support bone tissue formation at both experimental time points without adverse tissue reactions. Biomechanically, similar properties were obtained from nanoindentation analysis of bone formed following implantation of magnetic and control scaffolds. The results indicate that the osteoconductive properties of an HA scaffold are maintained following inclusion of a magnetic component. These provide a basis for future studies investigating the potential benefit in tissue engineering of applying magnetic stimuli to enhance bone formation. (C) 2017 Wiley Periodicals, Inc.

The production of Amarone wine is governed by a disciplinary guideline to preserve its typical features; however, postharvest infections by the fungus Botrytis cinerea (B. cinerea) not only represent a phytosanitary problem but also cause a significant loss of product. In this study, we tested a treatment with mild ozoniztion on grapes for Amarone wine production during withering in the fruttaio (the environment imposed by the disciplinary guideline) and evaluated the impact on berry features by a multimodal imaging approach. The results indicate that short and repeated treatments with low O3 concentrations speed up the naturally occurring berry withering, probably inducing a reorganization of the epicuticular wax layer, and inhibit the development of B. cinerea, blocking the fungus in an intermediate vegetative stage. This pilot study will pave the way to long-term research on Amarone wine obtained from O3-treated grapes.

Graphene is extremely resilient to in-plane stresses because of its high Young's modulus[1]; however, it can be easily bent to achieve complex folded structures, known as wrinkles [2]. Such 3D out-ofplane deformations occur both naturally3 and in solution-chemistry processes [4] and, as postulated in the literature, their curvature generate local potential centers with a short-range interaction [5]. The comprehension of the underlying mechanism beyond this phenomenon is fundamental for correlating the topographical properties of wrinkled graphene and its electronic structure. In order to investigate it, gold nanoparticles (NPs) were used to identify if and where they are pinned to wrinkles [6]. Here we report a morphological investigation of silver NPs coated by EG6OH interacting with the surface of wrinkled graphene. The organic coating was used to reduce the metal-graphene interaction. A combination of Scanning Electron Microscopy (SEM) and Scanning Probe Microscopies (namely Atomic Force Microscopy - AFM - and Lateral Force Microscopy - LFM) was used to elucidate the early stage organization of NPs on wrinkled graphene. Firstly, Contact AFM and LFM were used to characterize the morphology of the graphene surface and its wrinkles, respectively. In particular, LFM was able to distinguish clearly three types of wrinkles, characterized by different folded structures [7]. Then, NPs were deposited on the graphene surface by drop casting, observing their organization on the surface by means of Tapping Mode AFM and SEM. Correlative images show that NPs diffuse on the graphene surface reaching wrinkles, then they diffuse along the topographic step formed by the wrinkle as long as a defect is met. The type of wrinkle seems not to affect this behavior. References 1. Lee C et al. Science 2008;321:385-88 2. Vandeparre H et al. Phys Rev Lett 2011;106:224301 3. Meyer JC et al. Nature 2007;446:60-3 4. Zhang J et al. Phys Rev Lett 2010;104:166805 5. Guinea F et al. Phys Rev B 2010;81:035408 6. Pacakova B et al. Carbon 2015;95:573-79 7. Kim K et al. Phys Rev B 2011;83:245433

In order to assess decay in the mechanical characteristics of re-exposed Reinforced Concrete (RC), it is crucial to recon- struct the temperature time history and the evolution of strain and stress elds. In this paper, the state of the art of assessment methods is presented and applied to a real structure damaged by re. It is a prestressed RC industrial warehouse located in the outskirts of the city of Cagliari (Italy). The collected data of several assessment methods are presented in order to produce the owchart of an integrated approach for post- re investi- gation. Among the various techniques, the authors highlight a thorough laser scanner geometric survey and destructive and non-destructive testing. In addition, the temperature distribu- tion and its time history has been reconstructed by means of optical and Scanning Electron Microscopy, X-ray diffractom- etry, Thermogravimetric Differential Thermo-Analysis and calibrated Colorimetry. Actually, refurbishment is needed, but the structure withstood the re very well. Central columns displayed the most impor- tant damage, and several beams presented important de ec- tions having lost the prestressing actions of the tendons.

Background: The identification of calcium crystals in synovial fluid (SF) of patients with osteoarthritis (OA) represents an important step in understanding the role of these crystals in synovial inflammation and disease progression. Objectives: This study aimed to investigate the presence of calcium pyrophosphate (CPP) and basic calcium phosphate (BCP) crystals in SF collected from patients with symptomatic knee OA by scanning electron microscopy (SEM) coupled to x-ray energy dispersive spectroscopy, compensated polarized light microscopy (CPLM), and alizarin red staining. Methods: Seventy-four patients with knee OA were included in the study. Synovial fluid samples were collected after arthrocentesis and examined under CPLM for the assessment of CPP crystals. Basic calcium phosphate crystals were evaluated by alizarin red staining. All the samples were examined by SEM. The concordance between the 2 techniques was evaluated by Cohen ? agreement coefficient. Results: Calcium pyrophosphate and BCP crystals were found, respectively, in 23 (31.1%) and 13 (17.5%) of 74 OA SFs by SEM analysis. Calcium pyrophosphate crystals were identified in 23 (31.1%) of 74 samples by CPLM, whereas BCP crystals were suspected in 27 (36.4%) of 74 samples. According to ? coefficient, the concordance between CPLM and SEM was 0.83 for CPP, and that between alizarin red and SEM was 0.68 for BCP. Conclusions: The results of our study showed a high level of concordance between the 2 microscope techniques as regards CPP crystal identification and a lower agreement for BCP crystals. Although this finding highlights the difficulty in identifying BCP crystals by alizarin red staining, the use of SEM remains unsuitable to apply in the clinical setting. Because of the in vitro inflammatory effect of BCP crystals, further work on their analysis in SF could provide important information about the OA process.

The machining of shape memory alloys (SMAs), such as NiTi based alloys, is a very interesting and relevant topic for several industrial applications in the biomedical, sensor and actuator fields. Laser technology is one of the most suitable methods for the manufacturing of products in the aforementioned fields, mainly when small and precise features have to be included. Due to the thermal nature of this process, study of its effect on the functional properties of these materials is needed. Except for binary NiTi, few results on the laser machining of NiTi based alloys are available in the literature. In this work, thin sheets of Ni40Ti50Cu10 (at.%) were processed by a fibre laser and the effect of process speed on the material properties was analysed. Scanning electronic microscopy was adopted for observation of the laser cut edges' morphology. Chemical composition of the processed material was evaluated by energy dispersion spectroscopy and nanohardness measurements were used to estimate the heat affected zone. SMA functional properties were studied on both base and laser machined material. These characteristics are affected by laser machining for the presence of melted material; this effect can be minimised by increasing the laser process speed.

The objective of this paper is to study the morphology, structure, and composition, as well as the thermal-induced morphological, structural, and chemical changes of copper(Cu)/titanium nitride(TiN) bilayers versus Cu single layers, deposited on silicon substrates for microelectronic applications. These characterizations aimed to assess the reliability of Cu metallization for local interconnect and to investigate the barrier capability of TiN against Cu diffusion into the silicon (Si) substrate. Moreover, this paper provides a fundamental study of the temperature-induced interactions between Cu and Si, intermediated by the presence of a thin TiN layer. Cu thin films were sputtered onto Si substrates, with and without the interposition of thin TiN layers, and were successively annealed at temperature as high as 600. C. Different nitrogen flux percentages in the sputtering mixture (Ar + N-2) were used for the deposition of the barriers. X-ray diffraction (XRD) analyses were carried out in order to study the structural evolution of the layers, before and after the annealing. Scanning electron microscopy (SEM) observations gave information about the surface and cross section morphology, and spatially resolved energy dispersive X-ray Spectroscopy (EDS) profiles provided chemical information about the cross-sectional distribution of the atomic species and their possible interdiffusion. The barrier efficacy has been demonstrated by comparing the morphological and chemical modifications of the annealed Cu layers, with and without the presence of the TiN layer, and their effects on the electrical properties of the Cu films.

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