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As part of the Hitachi High-Tech America Inspire STEM Education Outreach Programme in the UK, a successful STEM (Science, Technology, Engineering and Math) education pilot has seen over 5000 students from 80 schools given the opportunity to use scanning electron microscopes (SEMs) for their own experiments. The collaborative project allowed students to design, propose, and execute experiments to give them hands-on experience with scientific research. Feedback from the project has been resoundingly positive, with many students gaining new skills and an interest in STEM, and it looks set to grow further to allow more students access to high-level scientific equipment. [ABSTRACT FROM AUTHOR]

It is impossible to remove tooth-colored restorations by mechanical means without unnecessary damage to the adjacent sound tooth structure. This study is aimed at investigating erbium-doped yttrium aluminum garnet (Er: YAG) laser (Hoya ConBio, VersaWave, CA, USA) in removing composite resin restorations and assessing the change in morphology of bonding surfaces using a scanning electron microscope (EDX, CAMSCANNER, 3200LV, UK). The investigators collected thirty extracted sound human premolar teeth for this investigation, and the conventional design class V cavity was prepared on the buccal surface of each specimen. The specimens were allocated randomly into three groups, according to the procedure used for the ablation of the composite restoration: group A (high-speed diamond fissure bur), group B, and group C (Er: YAG laser) using a different pulse repetition rate of 20 Hz (group B) and 25 Hz (group C). The AutoCAD software program (Autodesk, Inc., 2016) was used to calculate the surface area and the resulting dimensional change of the cavities after restoration removal. The cavities were filled with composite resin and randomly assigned into two groups conforming to the methods applied to eliminate the restoration; diamond turbine fissure bur and laser. In each group, two specimens were selected randomly for scanning electron microscope analysis of bonding surfaces. The least meantime for the composite resin removal was observed in the high-speed diamond bur, significantly less than both Er-YAG laser groups (p < 0.001). However, at a higher pulse repetition rate, time-consuming decreased. The results showed that laser is more conservative in removing composite resin restoration as the change was most remarkable in group A (0.800 mm), then group C (0.466 mm), and the slightest change is in group B (0.372 mm) (p = 0.014). The dentin surface of group A showed a smooth surface with no opened dentinal tubule and intact smear layer. In groups B and C, dentin surfaces were irregular, scaly, or flaky, and dentinal tubules were opened without a smear layer. Therefore, Er: YAG laser is effective for composite resin removal considering the parameters chosen in this study with fewer changes in cavity surface area and better microretentive features. [ABSTRACT FROM AUTHOR]

Introduction: Nanoparticles are now being viewed as fundamental or the basic building blocks of nanotechnology. The most significant property of nanoparticles is that they exhibit large surface area to volume ratio. The most efficient and effective nanoparticles today studied are the ones made of noble metals like that of silver (Ag), gold (Au), or platinum (Pt). The presence of biomolecules of the plant capped in AgNPs is found by Fourier transform-infrared analysis, shape and size, examined by scanning electron microscope (SEM) and X-ray diffraction (XRD). From XRD, the average size of AgNPs is found to be around 15 nm. Atomic force microscope proves to be very helpful in the determination and verification of various morphological features and parameters. Materials and Methods: Plant sample was collected from phytolabs and is extracted using aqueous method. 1 g of sample with water is boiled for 10 min at 55°C. The extract was filtered. To the filtrate, 1 molar silver nitrate solution was prepared. Overnight incubation was done in shake incubator. Results and Discussion: Ultraviolet spectroscopy was taken. The sample was taken at 200–800 nm. Out of which the peak was seen at 420 nm. Fourier transform infrared results confirm the presence of functional groups. SEM shows the image of synthesized silver nanoparticles from Phyllanthus emblica. The image clearly indicates the particle size range in 138 nm. Conclusion: Silver nanoparticles have been used as an antimicrobial agent in many industries. Products made from these are also approved by developed countries such as US, UK, and China. These antimicrobial activities are found useful for water treatment. Because of its ability to kill microorganisms, it offers an alternative to conventional methods and can be used in applications such as bandages, food and water storage, and pharmaceutical waste management. Furthermore, nanopaints are made using this. [ABSTRACT FROM AUTHOR]

Teleosauridae was a group of largely marine Mesozoic crocodylomorphs, typically considered as akin to "marine gavials" due to their elongate, tubular, polydont rostra that are indicative of a piscivorous diet. Here we show that these extinct crocodylomorphs were more anatomically, and perhaps ecologically, varied than previously thought. We report the first evidence of denticles in a teleosaurid tooth, revealed by scanning electron microscopic (SEM) analysis of a tooth from the holotype of "Steneosaurus" obtusidens. These denticles are cryptic, because they are microscopic, not contiguous along the carinae (instead forming short series), and are detectable only using SEM. This incipient denticle morphology is similar to that recently discovered in a closely related group of marine crocodylomorphs, the Metriorhynchidae. In particular, the denticulation morphology of "Steneosaurus" is similar to that of the geosaurin metriorhynchid Torvoneustes, indicating that these two taxa may have employed similar feeding styles and that "S." obtusidens may have been a nearshore ecological analogue to the more offshore, fast-swimming geosaurins. Previous authors have considered "S." obtusidens and Machimosaurus to be durophagous, but the discovery of denticulated teeth indicates that they had a more varied diet and feeding style, and included flesh slicing as part of their feeding toolkit. It is currently unknown how extensive denticulate carinae may be in Teleosauridae, and we hypothesise that cryptic denticles may also be present in other marine crocodylomorphs once they are subjected to SEM study. [ABSTRACT FROM AUTHOR]

In a previous study by Grima et al. Sci. Justice 52 (1) (2012) 49, it was shown that background particles can aid in the exclusion of firework particles which are indistinguishable from GSR. Issues relating to the persistence of such particle populations were presented. The scope of this project was to examine persistence on the hands in the context of possible post-display scene contamination and how this can affect GSR evidence, especially in light of possible GSR/firework mixtures. Persistence was investigated by recovering firework residues eight hours post-display following contact of the hands with bedding. In addition, particle profiling was carried out using SEM-EDX. Firework particle populations exhibited strong persistence in all displays, with not less than 667 particles persisting in each scenario. This factor challenges GSR evidence, especially if personnel stationed at display sites enter scenes of crime or come into contact with suspects after a display. A survey of UK police force practices following firework displays showed that authorities are not aware of the impact particle transfer may have on GSR evidence. Recommendations for the implementation of basic hygiene practices for particle transfer control have also been made. [ABSTRACT FROM AUTHOR]

• Concentrations of natural biopolymers in surface waters varied with seasons. • Biopolymer was beneficial to nanofiltration membrane fouling control. • Controlling, versatile layer formed by biopolymers was visualized. • Effectiveness of biopolymers was verified across seasons and countries. • Microfiltration, rather than ultrafiltration, is suggested before nanofiltration. Membrane filtration in various forms has become an increasingly used treatment method worldwide for the supply of safe drinking water. The fouling of membranes is commonly considered to be the major operational limitation to its wider application since it leads to frequent backwashing and a shortening of membrane life, and increased production costs. The components of natural organic matter (NOM) in surface waters have been reported previously to be important foulants of nanofiltration (NF) membranes, however, the potential beneficial effect of particular components of these 'foulants' has not been investigated or demonstrated to date. In this study, we have considered the roles of different organic materials including autochthonous NOM (e.g., biopolymers) and allochthonous NOM (e.g., humic substances) on the fouling of NF membranes by bench-scale tests with samples of two representative source waters (UK) taken in two different seasons (autumn and winter). Microfiltration (MF) and ultrafiltration (UF) were employed to generate two permeates, between which the presence of biopolymers (30 kDa – 90 kDa) is the major difference. We developed sequential filtration (MF/UF-NF) to investigate biopolymers' behaviours in NF process. The results showed that the accumulation of biopolymers on NF membranes can mitigate fouling by providing a protective layer in which medium-low molecular weight (MW) materials (e.g. humic substances) are separated by adsorption and/or size exclusion. The protective layers assisted by biopolymers were seen to be thicker under scanning electron microscope (SEM) observation and characterized by higher roughness (i.e. three-dimensional, spacial structure) and greater adsorptive capacity. Moreover, improvement on NF membrane fouling mitigation could be more significant in autumn, comparing to that in winter. The findings in this study were found to be repeatable in similar tests with samples of comparable raw waters in China, and will be important to the practical application of NF membrane systems in terms of a new approach to combating fouling in long-term operation. [Display omitted] [ABSTRACT FROM AUTHOR]

The article offers updates related to acoustic emission monitoring and scanning electron microscope facility in Great Britain. Physical Acoustics Ltd. (PAL) has partnered with Severn River Crossing (SRC) and the Highways Agency to monitor the main cables of the M48 Severn Suspension Bridge which links England to South Wales. A new Advanced Scanning Electron Microscope Facility was opened by Hitachi in the Cavendish Laboratories in Cambridge University in England.

Geopolymer is identified as a type of promising alternative binder to Portland cement due to its sustainability and excellent properties. This paper investigated the influence of two types of curing regimes (i.e. oven and microwave radiation curing) on the compressive strengths of geopolymer samples, facilitated by scanning electron microscope analysis, which was adopted in the interpretation of strength results. Besides, a comparative life cycle assessment based on Europe was conducted between geopolymer and Portland cement samples with details. Results indicate that it took less time to prepare precast geopolymer concrete with desired strengths using microwave radiation than oven curing. Meanwhile, the source of PFA would greatly influence the strength development of geopolymer samples. Finally, the preparations of geopolymer samples presents lower environmental burdens and CO 2 emissions than Portland cement samples, however, the quality and availability of PFA and GGBS in UK led to a re-evaluation of the environmental impacts and strengths of the precast geopolymer concrete in the near future. Image 1 • Oven and microwave radiation curing were used in precast geopolymer concrete preparation. • It took less time to prepare precast geopolymer concrete with desired strengths using microwave radiation than oven curing. • Regulated PFA with a quality control should be used in geopolymer preparation. • In UK's near future, the quality and availability of precursors led to a re-assessment of the environmental impacts and strengths of precast geopolymer concrete. [ABSTRACT FROM AUTHOR]

Titanium alloy was extensively used in aerospace industrial field. It has a great significance to directly reveal the deformation process as a function of application conditions. This work investigates the real-time deformation behavior of laser direct metal deposited (LDMD) Ti–6Al–4V alloy at 200 °C, using self-developed high temperature in-situ scanning electron microscope (SEM) tensile stage with a controlled heating system. The results showed that the microstructure of the sample comprised of columnar β grains with zigzag grain boundaries decorated by tilted α plates along the building direction. During uniaxial tensile, slip bands develop along the grain boundaries between α plates with increasing stress. Grain boundary sliding contributes to the high tensile elongation. Compared the mechanical properties along transvers tensile with those at room temperature, the tensile stress decreased and displacement increased at 200 °C. Therefore, higher elongation and reduction in cross-sectional area were identified at 200 °C than those at room temperature. The fracture of specimen at 200 °C shows obvious necking character and deep dimples with thin rims. Coalescence of slip bands at α/α interface creates voids and the coupling of voids nucleates micro-crack. α/α grain boundary interface constitutes path to the crack propagation. The high misorientation angle at columnar β grain boundary hinders the cracks propagation. Finally, the cracks accumulate along the columnar β grain boundary leading to fracture. • The microstructure deformation of LDMD Ti–6Al–4V alloy is studied by high temperature in-situ SEM tensile stage at 200 °C. • Slip bands development, cracks propagation, and columnar β GB hindering at 200 °C are investigated. • Temperature effect on the deformation mode and corresponding mechanical properties have been revealed. [ABSTRACT FROM AUTHOR]

This article offers news briefs related to the field of science and technology. For more than 2 decades, photomicroscopist Dee Breger of Drexel University in Philadelphia, Pennsylvania, has used artistic photographs from scanning electron microscopes (SEM) to lure the public into learning about science. Last fall, she offered an hour-long guided session on an SEM as part of an auction to raise money for educational software. The auction, organized by Galaxygoo, a San Francisco nonprofit, featured works of art inspired by science, including Breger's own SEM image of a penguin feather. In 2000, Aristides Patrinos brokered a truce between a U.S. government project to sequence the human genome and a competing, private effort led by J. Craig Venter. Now, the 59-year-old engineer-turned-science administrator is leaving the Department of Energy after 3 decades to run a company founded by Venter. Great Britain's Nicholas Shackleton died on January 24, 2006. He started out studying physics, switched to measuring minuscule isotopic differences in microscopic bits of ocean mud, and ended up establishing the metronomic qualities of climate change.

Reports the development of a scanning transmission electron microscope in Great Britain. Universities responsible for the success of the project; Effectiveness of the instrument in detecting and analyzing single atoms in small particles; Benefit of the development in attracting world class scientists and industries to the country.