Search

Aim: To investigate the level of agreement between the SEM 200 and Provisio® subepidermal moisture sacral delta measurements, which may indicate increased pressure injury risk, in healthy adults during 120 min of prolonged 60° head of bed elevation. This position, which requires the elevation of the patient's upper body at a 60° angle above the horizontal plane for an extended period, is used by clinicians to prevent or manage a patient's medical or surgical conditions. Design: This prospective exploratory study recruited 20 healthy adults during October 2021 and collected sacral subepidermal moisture delta measurements using the SEM 200 and Provisio® devices. Methods: Delta measurements were taken at 20‐min intervals over 120 min resulting in seven data collection timepoints. Descriptive statistics and a Bland Altman plot analysis were conducted. Results: A total of 280 sacral subepidermal moisture delta measurements were gathered or 140 per device. There were good levels of agreement between the two devices at baseline (T0) [mean 0.025; SD 0.137] and following 60‐ (T3) [mean 0.025; SD 0.111], 80‐ (T4) [mean −0.01; SD 0.177] and 100 min (T5) [mean 0.01; SD 0.129] of prolonged 60° head of bed elevation. Head of bed elevations can increase a patient's risk of sacral pressure injuries. In some countries, nurses have access to the SEM 200 and/or the Provisio® device, so our findings may increase nurses' confidence in the interchangeability of the device measurements, although further research is needed to confirm this. The SEM 200 and Provisio® subepidermal moisture scanners show promise in gathering similar objective pressure injury risk data which could prompt clinicians to implement prevention strategies. Impact: Current pressure injury risk assessment is largely subjective in nature. This quantitative study on healthy human sacral tissue found a good level of agreement in the SEM 200 and Provisio® subepidermal moisture scanners, which may increase nurses' confidence in the interchangeability of the devices in clinical practice. [ABSTRACT FROM AUTHOR]

Smart lignin hydrogels with pH responsive and magnetic properties was prepared by free radical polymerization from lignin and acrylamide. In order to improve its swelling properties, calcium carbonate as porefoaming agent was introduced to the polymer formulation, then magnetic particles (Fe3O4) was formed in the polymer by in situ reaction and coprecipitation. The results showed that degree of swelling of pH responsive hydrogels (PLH) containing the pore-foaming agent increased 47% compared to the original hydrogels (OLH) without pore-foaming agent, and the swelling rate of PLH reached 100% within 13.5 min under optimum pH conditions (pH = 6.8) which is a shorter amount of time, 1.5 times, compared to the OLH. The swelling-deswelling experiments showed that the hydrogels retained good reversibility and stability. Fourier transform infrared (FTIR) spectra indicated that the molecular chain of the PAM matrix hydrogels was successfully grafted on the lignin and the magnetic particles (Fe3O4) precipitated in the hydrogel. The X-ray diffraction (XRD) results showed that the magnetic particles in the hydrogels were composed of magnetite. The presence of a mesoporous structure was observed in scanning electron microscopy (SEM) images. The composition of hydrogels was analyzed by energy dispersive spectroscopy (EDS). The vibrating sample magnetometer (VSM) measurements also showed good magnetic properties. [ABSTRACT FROM AUTHOR]

Palm-epoxy hybrid composites were fabricated by incorporating palm leaf stem stalk (PLSS) powder at levels of 0 wt%, 5 wt%, 10 wt%, and 15 wt%. Physical, mechanical, and erosion characteristics of these composites were investigated. Incorporation of filler powder had a positive effect on the hardness and impact strength and a negative effect on the tensile and flexural strength of the composites. The erosion test varied the impact angle (45° to 90°), impact velocity (40 m/s to 80 m/s), and erodent particle size (40 µm to 100 µm). The erosion experiments were statistically designed using Taguchi's orthogonal arrays. It was found that the erosion rate of palm-epoxy composites decreased with increasing filler powder content, and that the composite filled with 15 wt% PLSS had the highest erosion resistance. The surface morphology of the eroded samples were examined using scanning electron microscopy. [ABSTRACT FROM AUTHOR]

In this study, Fe 3 O 4 magnetic nanoparticles (MNPs) were synthesized ( B-MNP ) and then modified with SiO 2 to form Fe 3 O 4 /SiO 2 core/shell MNPs. The Fe 3 O 4 /SiO 2 MNPs were chemically functionalized with chitosan so as to gain Fe 3 O 4 /SiO 2 /Chitosan ( CH-MNP ). The CH-MNP was functionalized with a macromolecule containing imide and phenylalanine precursors to gain Fe 3 O 4 /SiO 2 /Chitosan/imide/phenylalanine based MNPs ( CH-IM-MNP ). The differences in chemical structures of the synthesized MNPs were quantified by FTIR and TGA analyses, where grafting ratios of ca. 6 and 28% were calculated for CH-MNP and CH-IM-MNP nanoparticles, respectively. Nanocomposites were prepared by addition of very low (0.1 wt.% nanoparticle based on 100 parts by weight of epoxy) to epoxy/amine systems. Curing behavior of the blank and MNPs-incorporated nanocomposites were studied by nonisothermal DSC analyses varying heating rate, which allowed for giving useful insights into the effect of chemical surface functionalization of MNPs on the curing potential/behavior of epoxy/amine systems. Analysis of fracture surface of the blank and MNPs-incorporated systems using SEM micrographs revealed a very high potential of cure when CH-IM-MNP added to epoxy/amine formulation. [ABSTRACT FROM AUTHOR]

A novel hybrid nanomaterial based on silver nanoparticles, AgNPs, supported by 2,4-dihydrazino-6-(methoxypolyethyleneglycol)-1,3,5-triazine (mPEGTH) was prepared using solid phase technique. The synthesis process and the structural properties of the AgNPs were analyzed through X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmittance and scanning electron microscopy (TEM and SEM). The effect of seawater, and pH of solutions on the aggregation and zeta potential of Ag NPs were characterized and identified. The Ag/mPEGTH, hybrid materials produced well dispersion and exhibit a remarkable superiority in enhancing the anticorrosion performance of epoxy coatings and fulfill a significant synergistic effect in anticorrosion and self-healing performance for epoxy composite coatings. The new self-healing mechanism of Ag/mPEGTH nanomaterial for the epoxy coating defects is tentatively proposed and discussed. [ABSTRACT FROM AUTHOR]

The Upper Triassic Chang 6 sandstone, an important exploration target in the Ordos Basin, is a typical tight oil reservoir. Reservoir quality is a critical factor for tight oil exploration. Based on thin sections, scanning electron microscopy (SEM), X-ray diffraction (XRD), stable isotopes, and fluid inclusions, the diagenetic processes and their impact on the reservoir quality of the Chang 6 sandstones in the Zhenjing area were quantitatively analysed. The initial porosity of the Chang 6 sandstones is 39.2%, as calculated from point counting and grain size analysis. Mechanical and chemical compaction are the dominant processes for the destruction of pore spaces, leading to a porosity reduction of 14.2%–20.2% during progressive burial. The porosity continually decreased from 4.3% to 12.4% due to carbonate cementation, quartz overgrowth and clay mineral precipitation. Diagenetic processes were influenced by grain size, sorting and mineral compositions. Evaluation of petrographic observations indicates that different extents of compaction and calcite cementation are responsible for the formation of high-porosity and low-porosity reservoirs. Secondary porosity formed due to the burial dissolution of feldspar, rock fragments and laumontite in the Chang 6 sandstones. However, in a relatively closed geochemical system, products of dissolution cannot be transported away over a long distance. As a result, they precipitated in nearby pores and pore throats. In addition, quantitative calculations showed that the dissolution and associated precipitation of products of dissolution were nearly balanced. Consequently, the total porosity of the Chang 6 sandstones increased slightly due to burial dissolution, but the permeability decreased significantly because of the occlusion of pore throats by the dissolution-associated precipitation of authigenic minerals. Therefore, the limited increase in net-porosity from dissolution, combined with intense compaction and cementation, account for the low permeability and strong heterogeneity in the Chang 6 sandstones in the Zhenjing area. [ABSTRACT FROM AUTHOR]

The orthopoxvirus vaccinia virus (VACV) interacts with both actin and microtubule cytoskeletons in order to generate and spread progeny virions. Here, we present evidence demonstrating the involvement of PAK1 (p21-activated kinase 1) in the dissemination of VACV. Although PAK1 activation has previously been associated with optimal VACV entry via macropinocytosis, its absence does not affect the production of intracellular mature virions (IMVs) and extracellular enveloped virions (EEVs). Our data demonstrate that low-multiplicity infection of PAK1 MEFs leads to a reduction in plaque size followed by decreased production of both IMVs and EEVs, strongly suggesting that virus spread was impaired in the absence of PAK1. Confocal and scanning electron microscopy showed a substantial reduction in the amount of VACV-induced actin tails in PAK1 MEFs, but no significant alteration in the total amount of cell-associated enveloped virions (CEVs). Furthermore, the decreased VACV dissemination in PAK1 cells was correlated with the absence of phosphorylated ARPC1 (Thr21), a downstream target of PAK1 and a key regulatory subunit of the ARP2/3 complex, which is necessary for the formation of actin tails and viral spread. We conclude that PAK1, besides its role in virus entry, also plays a relevant role in VACV dissemination. [ABSTRACT FROM AUTHOR]

The article discusses the invention of scanning electron microscopy (SEM) imaging following the study of physicists Manfred Ardenne on the use of electron probes for scanning materials with electron beam. Topics include the improvements in sources of electron beam due to the commercialization of SEM, offering microscopy options such as X-ray analysis and optical imaging, and the use pf variable-pressure SEM (VPSEM) technology.

Metrology and control of critical dimensions (CDs) are key to the success of nanotechnology. Modern nanotechnology and nanometrology are largely based on knowledge developed during the last 10 to 20 years of semiconductor manufacturing. Semiconductor CD metrology entered the nanotechnology age in the late 1990s. Work on 130-nm- and 90-nm-node technologies led to the conclusion that precision alone is an insufficient metric for the quality assessment of metrology. Other components of measurement uncertainty (MU) must also be considered: 1. sample-to-sample measurement bias variation, 2. sampling uncertainty, and 3. sample variation induced by the probe-sample interaction. The first one (sample-dependent systematic error) is common for indirect and model-based CD metrologies such as top-down and cross-sectional scanning electron microscopy (SEM) and scatterometry (OCD). Unless special measures are taken, bias variation of CDSEM and OCD could exceed several nanometers. Variation of bias and therefore MU can be assessed only if reference metrology (RM) is employed. The choice of RM tools is very limited. The CD atomic force microscope (AFM) is one of a few available RM tools. The CDAFM provides subnanometer MU for a number of nanometrology applications. Significant challenges of CDAFM remain, such as the following: 1. the finite dimensions of the probe are limiting characterization of narrow high-aspect spaces, 2. the flexibility of the probe complicates positioning control, 3. the probe apex sharpness limits 3D AFM resolution, 4. the lifetime of atomically sharp probes is too short, and 5. adsorbates change properties and dimensions of nanometer-sized objects considerably. We believe that solutions for the problems exist; therefore, we will discuss the role of RM in nanometrology, current RM choices, and the challenges of CDAFM as well as suggest some potential solutions. [ABSTRACT FROM AUTHOR]

Aluminum oxide structures were grown on Cu-9 at.% Al(111) single crystals. Usually alumina grows in the form of an epitaxial thin film. The process is based on Al atom segregation and subsequent oxidation of the Al topmost surface. Strong temperature dependence of the alumina growth mode was observed during the oxidation of a Cu-9 at.% Al single crystal. In this work we have reported for the first time the formation of alumina wire-like nanostructures on the substrate surface during high-temperature oxidation at low pressure. The nanowire growth was observed during substrate annealing at 1070 K while annealing at 910 K led to the formation of a flat and continuous thin alumina layer. Morphology, chemical composition, and structure characterization of the prepared nanostructures was done by means of scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The experimental results point to the formation of Θ alumina phase nanowires due to surface segregation of Al atoms. Mechanism of alumina nanostructure formation is discussed. The experiment clearly showed that nanowire oxide structure growth can be obtained by a bottom-up process with a mass transfer from the substrate to the assembled nanostructure. [ABSTRACT FROM AUTHOR]

The raw material – residue of oil production from Huadian oil shale – was modified with cationic surfactants; the hydroxyl groups on the aggregated silica surface were alkylated directly. The structure of alkylated Si-hydroxyl on modified silica surface was characterized by means of infrared spectroscopy, nuclear magnetic resonance analysis, thermal gravimetric analysis and scanning electron microscopy analysis. The results showed that modification rate of hydroxyl groups on the surface of the modified silica obtained was about 84%. The modification conditions were optimized basing on application of the orthogonal experimental method, and the optimum parameters were as follows: the reaction temperature of water medium – 40 °C, pH value within the range of 9–10, and the molar ratio of cationic surfactant to silica hydroxyl on the surface – 2:1. [ABSTRACT FROM AUTHOR]

The friction and wear behaviour of the laser-textured surfaces sliding against a pin under the lubrication of the polyurea grease containing various additives were investigated using an UMT-2MT reciprocating friction tester. Results show that the dimple patterns have lower friction coefficients than that of the un-textured at lower sliding speed (0.015 m/s); however, the groove patterns have higher friction coefficients than that of the un-textured at all sliding speeds investigated in this article. Also, the anti-wear properties of the base polyurea grease and the base grease containing several additives on the textured and un-textured surfaces are discussed. Scanning electron microscopy and X-ray photoelectron spectroscopy were adopted to reveal the lubricating mechanism of different additives on the laser-textured surfaces. [ABSTRACT FROM AUTHOR]

The present study focuses on the recycling of gneiss rock waste generated by the ornamental rock industry for manufacturing vitrified floor tile products. The gneiss rock waste came from a rock-cutting plant located in Santo Antônio de Pádua-RJ, Brazil. Initially the waste sample was characterized for chemical composition, X-ray diffraction, particle size, morphology, and pollution potential. Floor tiles containing up to 47.5wt.% waste were prepared. The tiles were tested to determine their physical-mechanical properties (linear shrinkage, water absorption, apparent density, and flexural strength). Microstructural evolution was carried out by scanning electron microscopy. The results indicate that the gneiss rock waste could be used for vitrified floor tile production, resulting in a new possibility for recycling this waste and conserving natural resources. [Copyright &y& Elsevier]

Abstract  Data are given on the test object for scanning electron microscopy in which the components (ridges) are of trapezoidal profile and have large angles of inclination for the side walls. The width of the top surface of a projection is less than 10 nm. Methods have been developed for measuring such dimensions of test objects on standard scanning electron microscopes. [ABSTRACT FROM AUTHOR]

The article presents a study conducted in Japan which looked into the cast-soldering method to the embedded keeper of magnetic attachment on the teeth. Three types of casting machines were used in performing the cast-soldering which include suction pressure type, vacuum pressure type and centrifugal type. Metallic microscopy and scanning electron microscopy were employed during the observation of the interface between the keeper and the casting alloy wherein a black layer was observed.

The article offers brief information on several products including the SmartSite RS portable stress analyzer from Rigaku, the GAIA3 Focused Ion Beam Scanning Electron Microscope (FIB?SEM) workstation from Tescan, and the Xi3400 Automated X-ray Inspection System from Nordson DAGE.

The REMEDIE system for reflection electron microscopy and electron diffraction at intermediate energies (0.5–20 keV) has been rebuilt with an improved imaging resolution of better than 10 nm, a convenient and versatile system for observation diffraction patterns and provision for specimen preparation and treatment suitable for surface structural studies. The current capabilities of the instrument are illustrated by results obtained from cleaved and annealed silicon (111) surfaces with or without thin deposited silver and gold layers. [ABSTRACT FROM AUTHOR]

The article evaluates several electronic devices for failure analysis including the TriboLat chemical mechanical polishing (CMP) Process and Materials Characterization System from Bruker's Nano Surfaces Division, Helios G4 plasma focused ion beam (FIB) system and Themis S system from Thermo Fisher.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010. [ABSTRACT FROM PUBLISHER]

The article offers information on several life science laboratory products, including the CoolCLAVE personal lab sterilizer by AMS Biotechnology, the AFS 8D and AFS 16D water purification systems by EMD Mlllipore, and the PP3000T cryopreparation system for scanning electron microscopy (SEM) by Electron Microscopy Sciences

The article reviews products, including a cell imaging system from GE Healthcare, an ion beam/scanning electron microscopy workstation from Carl Zeiss, and a confocal laser scanning microscope metrology system from Olympus Europe.

The article reports on the results of research which was conducted in an effort to develop a method for the scanning electron microscopic study of plaque on periodontal suture material. Researchers were able to successfully develop a technique and used it to examine plaque samples from humans. They found that the plague that they observed ranged from predominantly coccal forms to mats which consisted of rods, cocci and filaments.