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Background: Resin-based pit and fissure sealants, used to prevent dental caries, can experience abrasive wear. This study aimed to assess the abrasive wear of experimental pit and fissure sealants (DIF) compared with the other commercial pit and fissure sealants by measuring surface roughness, volume loss, and ultrastructure after chewing simulation at different time points. Methods: Specimens were divided into five groups (n = 10): Clinpro™(CP), Teethmate™ White (TW), Teethmate™ Natural (TN), experimental sealant (DIF), and Filtek™ Supreme Flowable Restorative (FC). They underwent chewing simulation with 120,000, 240,000, and 360,000 strokes. Surface roughness and volume loss were measured with a profilometer, and ultrastructures were assessed using scanning electron microscope (SEM). Results: All specimens showed a significant increase in surface roughness after chewing simulation. FC had the highest roughness (p < 0.001) whereas DIF did not differ from other groups (p > 0.05). All materials experienced significant volume loss. Sealant types and chewing cycles affected volume loss, with CP showing the highest and TW the lowest (p < 0.001). SEM analysis revealed worn areas with circular or oval shapes, with CP and TN having larger diameters and TW the smallest. Conclusions: DIF showed acceptable surface roughness and wear resistance compared to other commercial products after chewing simulation. [ABSTRACT FROM AUTHOR]

Wire-cut electrical discharge machining (wire-cut EDM) was the primary method for producing Bren gun charging handlebars due to its high precision demands. However, the frequent breakage and damage of the wire electrode presented significant obstacles, negatively impacting surface quality, production time, and manufacturing costs. To address these challenges, an L9 orthogonal array was employed to investigate surface quality, material removal rate, and wire surface quality. Following experimentation, fresh and broken electrodes underwent examination using a scanning electron microscope (SEM). Surface damage and roughness were analyzed through SEM observations and histogram mean values. Initially, Artificial Neural Network (ANN) models were developed. The optimal ANN model (4–9-2) was then integrated with a multi-objective Genetic Algorithm (GA) for optimization. This combined approach yielded the following optimal parameter combinations: peak current of 2.513 A, pulse on time of 25.642 µs, wire feed rate of 9.999 m/min, and pulse off time of 7.975 µs. Three confirmatory experiments were conducted using these optimized parameter values. The errors between the GA-predicted and confirmatory results for surface roughness (Ra) and material removal rate (MRR) were 1.19% and 2.29%, respectively. Compared to the company's previous performance, the confirmatory results demonstrated a 39.37% improvement in Ra while maintaining wire integrity, albeit with a 10.63% decrease in MRR. This research highlights a successful approach to enhancing machining quality and optimizing the wire-cut EDM process for defense applications. [ABSTRACT FROM AUTHOR]

As tailpipe emissions have decreased, there is a growing focus on the relative contribution of non-exhaust sources of vehicle emissions. Addressing these emissions is key to better evaluating and reducing vehicles' impact on air quality and public health. Tailoring solutions for different non-exhaust sources, including brake emissions, is essential for achieving sustainable mobility. Studying emissions from vehicles in real-world scenarios provides a better understanding of their environmental impact compared to laboratory testing alone. This study presents findings on the direct measurement of brake particles and the characterization of this source of particulate matter in real-world conditions using a mobile laboratory. In situ measurements of particle concentration and size distribution showed good agreement with previous laboratory studies, indicating the suitability of the approach to investigate break particle emissions during real-world operation. The study demonstrates that particle size distributions can vary based on the temperature of the brake disk, which is influenced by the initial braking speed, with significant variations observed between speeds of 60, 80, 100, and 120 km/h. Particles with sizes between 6 and 523 nm were released into the air from the brake system, although it is likely that larger particles were also emitted but not captured due to the upper detection limit of the Engine Exhaust Particle Sizer. During harsh braking events, such as decelerations of 4.2 m/s2 from 120 km/h, a concentration of up 106 (#/cm3) was measured for particles under 8 nm. Moreover, scanning electron microscope analysis revealed that nanoparticles are present in the form of agglomerates, whose shape can change depending on the formation process. Elements present in the particles comprised mainly iron, copper, and aluminium, indicating wear of the brake pad materials and disk components. [ABSTRACT FROM AUTHOR]

Background: This study aims to compare design, phase transformation behavior, and torsional resistance of the ProGlider (PG) and ProTaper ultimate slider (PUS) and to compare the performance of two files in the glide-path preparation of a double-curved artificial canal. Methods: Scanning electron microscopy, micro-computed tomography, and differential scanning calorimetry were used to characterize the samples. A torsional resistance test was performed to obtain ultimate strength and distortion angle. Simulated glide-path preparation was conducted with a double-curved resin canal, and both PG and PUS were operated on by 300 and 400 rpms. Maximum screw-in force, torque generated during canal shaping, number of pecking strokes to reach the apex were compared between groups. After canal shaping centering ratio and alteration of files were assessed. Statistical analyses were performed using the Mann-Whitney U test, and the Kruskal-Wallis test with Bonferroni correction. A p value less than 0.05 was considered significant. Results: While the PG had a square cross-section, the PUS had variable square and rhomboid cross-sections and alternating cutting-edge. PG and PUS have austenitic transformation starting and finishing temperatures of 24–25℃, and 57–59℃, respectively. Ultimate strength of PUS are superior to that of PG, whereas the distortion angle of PG is greater than that of PUS (p < 0.05). The maximum screw-in force and clockwise torque generated during glide-path preparation were highest in the PUS group rotated at 300 rpm (p < 0.05). Shaping with the PG at 300 rpm and shaping with the PUS at 400 rpm exhibited comparable maximum screw-in forces. There were no significant differences in the number of pecking strokes to reach the apex and centering ability among groups shaped with PG and PUS at both rotation speeds. PG shaped at 400 rpm demonstrated severe alteration on its surface, while PUS shaped at 300 and 400 rpms exhibited comparable surface alterations. Conclusions: PG has a constant square cross-section, while PUS has a variable cross-section and alternating cutting-edge. Using PUS at recommended speed of 400 rpm ensures safe use with minimal screw-in force and surface alteration. At recommended speeds, both PG and PUS perform comparably and are safe for double-curved canals. [ABSTRACT FROM AUTHOR]

Questioned document examination is one of the most challenging tasks in the field of forensic science. Examining the document without destroying its integrity is difficult in such cases. Microscopic examination is a noble and mostly non-destructive approach in document examination. It enables the examiner to visualize the evidence in the document, which would have been otherwise difficult with unaided eyes. The purpose of the study was to establish the importance of microscopic examination in document examination. A critical review of 60 years, from 1963 to 2023, of various research papers from different journals has been conducted. Applications of various microscopes including stereo microscopes, digital microscopes, scanning electron microscopes (SEM), and atomic force microscopes (AFM) were reviewed. Compared to the basic examinations performed before the year 2000, there was a remarkable evolution involving complex examinations with more precise results after the year 2000. Microscopy helped solve almost all kinds of problems involved in document examination. Among all microscopes, the stereo microscope was found to be a prominent tool in document laboratories. Certain limitations were also listed for microscopic examination over spectroscopic methods. However, microscopes have been the tool of choice for forensic document examiners. [ABSTRACT FROM AUTHOR]

Ti6Al4V is a widely used titanium alloy known for its excellent combination of mechanical properties, corrosion resistance, and biocompatibility. However, to ensure its effectiveness in various applications, it is important to understand the mechanical and fracture behavior of the alloy in the presence of a notch. In the present study, the effect of notch root radius on mode I fracture toughness of Ti6Al4V alloys with a nearly bimodal microstructure has been investigated. Fracture toughness tests were conducted on compact tension (CT) specimens with five different notch root radii. The experimental results demonstrate that the apparent fracture toughness, K IA , increases linearly with the square root of the notch root radius. Further to elucidate the results, a 2D elastoplastic finite element analysis is performed on the CT specimens using cohesive zone model. The simulation results are in good agreement with the experimental data. The study also reveals that the apparent fracture toughness is independent of the notch root radius below a critical value, estimated to be approximately 50 μ m . Finally, the scanning electron microscopy of the fracture surfaces has been examined. The micrographs reveal void coalescence and dimple regions indicating the ductile nature of the fracture process. [ABSTRACT FROM AUTHOR]

To examine ultrastructural changes in the trabecular meshwork (TM) in patients with primary and secondary glaucoma using scanning electron microscopy (SEM). This was a qualitative descriptive hospital-based study on the ultrastructure of the TM. Pure TM samples were collected after microincisional trabeculectomy from 26 patients with primary or secondary glaucoma and 10 control samples from eye bank donor corneas. SEM was used to analyze structural changes in the TM beams, corneoscleral meshwork (CSM), and juxtacanalicular (JCT) regions. Morphological features were compared between groups and correlated with histopathological findings. SEM revealed flattened and broadened TM beams in the JCT, resembling controls, often with a dumbbell configuration. Histopathological examination (HPE) and SEM showed rounded TM beams with considerable thinning, especially in primary angle-closure glaucoma (PACG), compared to primary open-angle (POAG) and pseudoexfoliation glaucoma (XFG). Maximum thinning in all primary glaucoma occurred in the CSM region, with minimal changes in the JCT region despite a reduction in cellularity in both regions. In steroid glaucoma, amorphous, glistening material was found on the TM beams in the JCT and CSM. XFG eyes displayed vesicular bodies adjacent to fibrillar material scattered diffusely over the TM beams, particularly in the CSM, differing from the platelet clumps seen in regular blood clots. TM beam thinning in primary glaucoma primarily affects the CSM region, sparing the JCT region. Amorphous deposits or vesicular bodies, seen only in steroid-induced glaucoma and XFG, suggest different mechanisms of TM damage in these glaucoma types. [ABSTRACT FROM AUTHOR]

A unique morphology was fabricated using melt mixing of polysulfone (PSU) and nylon 6, 6, as well as organically modified clay to produce two blended nanocomposite compositions (80/20 and 60/40 w/w) of polysulfone and nylon 6, 6. The morphology of PSU/Nylon 6, 6 blend nanocomposites with various amounts of clay has been examined using scanning electron microscope (SEM), transmission electron microscope (TEM), and wide-angle X-ray diffraction (WAXD). In the case of 80/20 (w/w) PSU/Nylon 6, 6 without clay, the Nylon 6, 6 is dispersed in the PSU matrix with an average particle size of about 6.81 micrometers (μm). After adding clay (2%, 4%, and 8%), the domain size of nylon 6, 6 decreases, although the decrease rate is much slower than initially observed. However, we discovered that when the organoclay level exceeds 2%, the matrix-domain structure transforms into a co-continuous morphology for the 60/40 (w/w) blends. The TEM studies clearly demonstrate that the organoclay preferentially positions itself in the nylon 6, 6 phase, exhibiting a high degree of exfoliation, while the PSU phase of the nanocomposites remains devoid of clay, irrespective of the amount present. This study indicates that the size of clay platelets dispersed in the PSU/Nylon 6, 6 blend plays an important role in determining the morphology and stability of these blends. Moreover, the co-continuous structures were stable against further annealing at high temperatures, thus inhibiting the coalescence of the dispersed phase in addition to reducing interfacial tension. [ABSTRACT FROM AUTHOR]

Aim: Evaluation of root-end cavities for the existence of microcracks and smear layer with laser, ultrasonic tip by conventional bur, and control group in single-rooted tooth by scanning electron microscope (SEM). Methodology: Fifty-two extracted fully developed single-rooted teeth were decoronated, cleaned, shaped, and obturated with F2 GP, and 3 mm roots were removed. Laser, ultrasonic tip (AS 3Dretro-tip on Newtron-SATELEC, Acteon), and conventional bur (size 010 round) were used to create root-end preparation. No root-end cavities were produced in the control group. SEM was used to check all samples for microcracks and smear layers. Results: A significant difference was found between microcrack formation in laser and conventional bur preparation (P = 0.002), and ultrasonic and laser (P = 0.015). Nonsignificant difference was found between ultrasonic and conventional bur (P = 0.046). The study concluded that maximum cracks were seen in conventional bur formation at the apical end of the root (0.85 ± 0.36) followed by the ultrasonic method (0.54 ± 0.23). Conclusion: Root-end cavities prepared with laser give fewer microcracks and less production of smear layer compared to the ultrasonic tip and conventional bur. [ABSTRACT FROM AUTHOR]

To achieve carbon neutrality, a reduction in car body weight is essential. Multi-material structures that use lightweight materials such as carbon fiber-reinforced polymers (CFRP) and aluminum (Al) alloy are used to replace parts of steel components. This multi-material method requires specific joining techniques for bonding dissimilar materials. Friction stir spot welding (FSSW) is one of the joining techniques used for joining dissimilar materials, enabling rapid and strong joints. FSSW for bonding A5052 Al alloy and carbon fiber-reinforced thermosetting resin (CFRTS) utilizing composite laminates with integrally molded thermoplastic resin in the outermost layer has been developed. However, joints using this method cause pyrolysis due to excessive frictional heating at the tool's bottom, which may affect joint strength and promote corrosion in Al alloy. Therefore, this study developed new tools, a concave-shaped tool without a probe, a concave-shaped tool with a probe and a conventional FSSW tool, and investigated the influence of heat distribution and joint strength using the three new tools. The newly developed concave-shaped tool with a probe suppressed 7% of maximum heat input, decreased the pyrolysis area of epoxy resin by 47%, and increased joint strength by 4%. Finite element analysis also showed the suppression of heat input through the newly developed concave-shaped tool with a probe, achieved by reducing the contact area between the tool and Al alloy. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of the growth and structure properties of Pb 1 − x EuxTe, (x = 0. 0 5) epitaxial films with 0.5–1 μ m thickness, grown on BaF2 and SiO2 substrates oriented in the (111) direction, by the molecular beam condensation method in a vacuum of 10 − 4 Pa with the use of an additional compensating source of Te vapor during the growth process. The optimal conditions for obtaining structurally perfect ( W 1 / 2 = 9 0 –100 ′ ′ ) epitaxial films were established: T sub = 5 7 3 –623 K; T Te = 4 1 0 K; υ c = 8 –9 Å/s. It was determined that conductivity inversion occurs at the temperature of the compensating source 410 K. [ABSTRACT FROM AUTHOR]

A sample containing microparticles of two different uranium materials with distinct uranium isotopic compositions was analyzed during an international experiment. Mass spectrometric analysis of 25 particles revealed that, within the measurement error, six particles had an isotopic composition consistent with that of the first material, and three particles were consistent with the second material. However, the uranium isotopic composition of the remaining 16 particles did not match either of the known materials. This indicates that the preliminary examination of uranium microparticles by scanning electron microscopy can identify particles carrying information about the isotopic composition of the source materials. [ABSTRACT FROM AUTHOR]

Addressing the need for sustainable construction materials that minimize environmental impact and reduce CO2 emissions, particularly in OPC compositions. Assessing alccofine and metakaolin in OPC compositions to determine their impact on concrete strength, durability, and microstructure in alkaline environments for sustainable material development. Experimental investigation involved incorporating alccofine and metakaolin into OPC concrete mixes, creating binary and ternary blended systems. Modified concrete specimens were subjected to various alkaline attacks using diluted solutions of magnesium sulfate (MgSO4), sodium sulfate (Na2SO4), and sodium chloride (NaCl) both individually (5%) and in combination (2.5%), resulting in significant improvements in concrete strength and durability. The modified concrete exhibits enhanced resistance to alkaline attacks, reduced weight and compression strength loss, and superior performance in Base Durability Factor (BDF) and Base Attack Factor (BAF) compared to conventional specimens. Scanning electron microscopy (SEM) study of the altered concrete's microstructure shows that it has a densely packed microstructure, which increases its load-bearing capability. Mineral admixtures aid pore clogging, leading to denser, more alkali-resistant concrete due to finer particles. Notably, Alccofine and metakaolin offer effective solutions for sustainable construction materials, aiding in the decrease of CO2 releases during cement production and addressing critical gaps in sustainable material development. [ABSTRACT FROM AUTHOR]

Bangasternus planifrons (Brullé, 1832) specimens collected from Ankara‐Bala were studied. The paper presents a scanning electron microscopic examination of ultrastructural features of aedeagus and spermatheca of Bangasternus planifrons (Brullé, 1832) (Coleoptera: Curculionidae: Rhinocyllini) from Türkiye for the first time. The fact that Bangasternus is a genus with three species in Türkiye makes the study more important. Accordingly, detailed investigation of aedeagus and spermatheca is very important to obtain new diagnostic characteristics in Bangasternus. The parts which include systematic characters such as spermatheca, genital spicule, sternite eight and coxite figures were drawn in detail and these characters were discussed on species, genera and tribus levels. While significant differences were observed among the species in genital spicula, coxite, stylus and spermateca, a difference that would reveal a genus discrimination character by evaluating these structures could not be obtained according to the available findings. Photos in stereomicroscope and scanning electron microscope are also given in the text. [ABSTRACT FROM AUTHOR]

Metal 3D printing has revolutionized manufacturing with its additive approach, offering many advantages. However, a major hurdle has emerged: optimizing heat treatment for 3D-printed titanium and nickel alloys, especially for aircraft parts. This challenge has made it difficult to achieve the desired mechanical properties and performance. Researchers have been constantly developing and improving new methods to address these issues. This study explores heat treatment methods for Ti-6Al-4 V and Inconel 718 alloys created using Direct Metal Laser Sintering (DMLS). The specimens have undergone an initial heat treatment at 800 °C for 2 h in an argon-free environment, followed by a two-stage aging process. After aging, these alloys have been characterized using progressive techniques like hardness testing, optical microscopy, density measurement, X-ray topography, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Analysis with these methods reveals that the proposed 3D-printed alloys exhibit improved structure and properties. [ABSTRACT FROM AUTHOR]

In recent years, 3D printing has a major influence in the industrial revolution and brings a lot of change to mechanical properties. Fused deposition modelling method has been used here form making a composite material. Before printing, initially the samples are designed with ASTM standard like tensile using on shape software and then convert to stl file format. After that, the digital file is sliced with 60%, 80%, and 100% infill density and produced using VIPER SHAREBOT 3D Machine. The chopped carbon fiber/PLA filament were used for making composites materials. All the samples are testing under mechanical testing machines and the average values are reported. The fractured tested samples were used for scanning electron microscope analysis to see how much fiber and void presented in tensile specimen. Based on the experimental results, it suggested that high infill density 100% produces maximum tensile strength, tensile modulus, and tensile stress-strain, ultimate strain, compared to other chopped carbon fiber reinforced PLA composites. Carbon fibre chopped the unique properties of reinforced PLA composites make them suitable for high-performance skateboard decks, lightweight luggage handles, and high-stiffness bicycle frames, advanced prosthetic limbs, biodegradable surgical instruments, and 3D-printed aerospace components. [ABSTRACT FROM AUTHOR]

Invasive fungal infections including invasive pulmonary aspergillosis (IPA) generally have a poor prognosis, because the fungi spread throughout various organs. Therefore, it is important to accurately identify the fungal species for treatment. In this article, we present the results of pathological and molecular morphological analyses that were performed to elucidate the cause of respiratory failure in a patient who died despite suspicion of IPA and treatment with micafungin (MCFG). Pathological analysis revealed the existence of cystic and linear fungi in lung tissue. The fungi were identified as Aspergillus fumigatus (A. fumigatus) by partial sequencing of genomic DNA. Correlative light microscopy and electron microscopy (CLEM) analysis confirmed that fungi observed with light microscopy can also be observed with scanning electron microscopy (SEM) using formalin-fixed paraffin-embedded tissue sections. SEM revealed an atypical ultrastructure of the fungi including inhomogeneous widths, rough surfaces, and numerous cyst-like structures of various sizes. The fungi showed several morphological changes of cultured A. fumigatus treated with MCFG that were previously reported. Our results indicate that integrated analysis of ultrastructural observation by SEM and DNA sequencing may be an effective tool for analyzing fungi that are difficult to identify by conventional pathological analysis. [ABSTRACT FROM AUTHOR]

Gamma irradiation was applied to the tachyzoites Toxoplasma gondii virulent strain at doses of 0.25, 0.5, 1, 1.5 and 2 KGy. Radiation's effects were assessed both in vivo and in vitro. In vitro, the modest dosage of radiation, 0.25 KGy, showed 97% tachyzoites viability with only slight surface abnormalities and a normal crescent form using a scanning electron microscope. Protein analysis by SDS‐PAGE demonstrated that while higher doses of radiation altered the protein banding profile, the 0.25 KGy irradiated tachyzoites showed no significant changes compared to the control (non‐irradiated tachyzoites). While, tachyzoites exposed to the higher dose of irradiation (1, 1.5 and 2 KGy) resulted in the appearance of a new protein band as the molecular weights detected were 60, 30 and 10 kDa for antigens prepared from tachyzoites exposed to 1 kDa, and 1.5 and 60, 28 kDa for antigen prepared from tachyzoites exposed to 2 KGy. The immunogenicity of the tachyzoites exposed to radiation did not reveal any significant change in comparison with no irradiated tachyzoites when tested by ELISA using sheep‐infected sera. A study conducted in vivo evaluated the infectivity of irradiation tachyzoites by inoculating mice with a 2500 tachyzoites virulent strain/mouse. There are six groups of mice, each with twelve animals, for the six doses of radiation. Mice harbouring irradiation tachyzoites remained viable until 40 days post‐inoculation. On the other hand, the mice of control group had a mean survival time of 6.5 ± 0.22 days, and none of them survived past 7 dpi. Comparing the attenuated T. gondii tachyzoites at 0.25 KGy to the control group and other groups injected with irradiated tachyzoites, the results showed statistically significant increases in total IgG. Compared to other irradiation groups, the group injected with 0.25 KGy irradiated tachyzoites had a considerably higher level of IFN γ and IL17 (p < 0.000001). The groups which received 0.25 and 0.5 KGy irradiated tachyzoites as an injection showed no discernible variation in their higher levels of IL12. The findings imply that gamma irradiation was successful in reducing the pathogenicity of the T. gondii virulent strain while preserving the potential of the irradiated tachyzoites to induce an immunological reaction. An investigation into this immune response's immunoprotective potential is advised. [ABSTRACT FROM AUTHOR]

In the realm of railroad transportation, the switch sliding baseplate constitutes one of the most crucial components within railroad crossings. Wear defects occurring on the switch sliding baseplate can give rise to issues such as delayed switch operation, inflexible switching, or even complete failure, thereby escalating the risk of train derailment. Consequently, the detection of wear defects on the switch sliding baseplate is of paramount importance for enhancing traffic efficiency and guaranteeing the safety of train switching operations. Micro-cutting defects, which are among the most significant defects resulting from wear, exhibit complex and diverse morphological and characteristic features. Traditional random sampling methods struggle to capture their detailed characteristics, leading to inadequate accuracy and robustness in the detection process. To address the above-mentioned issues, the YOLOv5s algorithm has been refined and subsequently applied to the detection of micro-cutting defects generated by wear on the switch sliding baseplate. The experimental results demonstrate that, in comparison with the currently prevalent mainstream target detection algorithms, the improved model can attain optimal recall rates R, mAP@0.5, and mAP@0.5:0.95. Specifically, when contrasted with the original YOLOv5s algorithm, the improved model witnesses significant enhancements in its precision rate P, the recall rate R, mAP@0.5, and mAP@0.5:0.95, with increments of 1.26%, 5.6%, 9.1%, and 8.92%, respectively. These improvements fully corroborate the performance of the proposed model in the context of micro-cutting defect detection. [ABSTRACT FROM AUTHOR]

The current study focuses on the creation of epoxy composites with cotton/bamboo woven fabric reinforcement. The effect of alkali treatment with varying (1, 2, and 3 wt.%) of NaOH on mechanical characteristics such as tensile, impact, flexural, compression, and interlaminar shear stress is explored and compared to those of the untreated cotton/bamboo fabric. The composites were made using a compression moulding process with four different fibre loadings (30, 35, 40, 45, and 50 wt.%). The mechanical characteristics of the composites were studied and their structure was evaluated by using a scanning electron microscope (SEM). The cotton/bamboo/epoxy composite with 2 wt.% NaOH at 45 wt.% fibre loading was found to have better mechanical properties when compared to the others. [ABSTRACT FROM AUTHOR]

In this study, the structure of the papillae in the tongue of Morkaraman sheep was investigated by light (LM) and scanning electron microscopy (SEM). The aim of this study was to investigate the morphology and topographic distribution of the lingual papillae of the tongues of Morkaraman sheep breed. Adult male Morkaraman sheep tongues were used in the study. Tongue samples for light and scanning electron microscopy were taken from the apex, corpus, radix and torus lingua regions of the upper surface of the tongue and the lower surface of the tongue tip. Two types of taste papillae, papillae fungiformis and vallata, were observed on the tongue. Papillae fungiformis were found under the tip of the tongue, on the upper surface and sides of the tip and body of the tongue and on torus lingua. Papillae vallata were observed on both posterior sides of the torus lingua of the tongue. SEM examination showed that the surface of the papillae was smooth and there were no taste pores opening to the surface. On LM examination, filiform papillae at the lingual apex were common in materials. These papillae had secondary keratin extensions on the main body. The light and scanning electron microscopic structures of the taste papillae on the tongue of Morkaraman sheep were examined and their similarities and differences with other ruminant species were determined. [ABSTRACT FROM AUTHOR]

Cotesia gregalis Yang et Wei (Hymenoptera: Braconidae) is a gregarious koinobiont endoparasitic wasp attacking the larvae of fall webworm, Hyphantria cunea, an important invasive insect pest in China. To better understand the parasitic wasps' mating and parasitic behaviors, we examined the morphology of the antennae of adult C. gregalis, as well as the type, number, and distribution of antennal sensilla, via scanning electron microscopy. The antennae of female and male C. gregalis are filiform and comprise a scape, pedicel, and 16 flagellomeres. The female antennae are significantly shorter than those of male. A total of nine morphological types of antennal sensilla (mechanoreceptor and chemoreceptor) are presented in both sexes, including four mechanoreceptors (sensilla chaetica [two subtypes], sensilla trichodea and Böhm bristles); five chemoreceptors (sensilla basiconica [two subtypes], sensilla placodea, sensilla styloconica, and sensilla coelocapitula). There is no difference in the type and distribution of antennal sensilla between males and females, but the number and length of some antennal sensilla show sexual dimorphism. The functional morphology of the sensilla of C. gregalis is discussed by comparison with other parasitic wasps. These findings provide foundation for further research on the chemical communication and host localization mechanisms of C. gregalis. Research Highlights: The first report of morphology and distribution pattern of the antennal sensilla in C. gregalis is discussed.A total of seven main types and nine antennal sensilla subtypes are observed in male and female C. gregalis.The type and distribution of antennal sensilla in males and females are identical; however, the number and length of certain antennal sensilla show sexual dimorphism. [ABSTRACT FROM AUTHOR]

Cathodoluminescence (CL) characterization technology refers to a technical approach for evaluating the luminescent properties of samples by collecting photon signals generated under electron beam excitation. By detecting the intensity and wavelength of the emitted light, the energy band structure and forbidden bandwidth of a sample can be identified. After a CL spectrometer is mounted on a scanning electron microscope (SEM), functions are integrated, such as high spatial resolution, morphological observation, and energy-dispersive spectroscopy (EDS) to analyze samples, offering unique and irreplaceable advantages for the microstructural analysis of certain materials. This paper reviews the applications of SEM-CL systems in the characterization of material microstructures in recent years, illustrating the utility of the SEM-CL system in various materials including geological minerals, perovskite materials, semiconductor materials, non-metallic inclusions, and functional ceramics through typical case studies. [ABSTRACT FROM AUTHOR]

Image denoising is an effective way to enhance the quality of scanning electron microscope (SEM) images, and improve the accuracy of detection analysis and automatic operation. However, most existing denoising methods rely on global parameters and are not suitable for noise removal in all regions of the image. To address this issue, this paper proposes a denoising method based on the adaptive anisotropic partial differential equations (AAPDE), which can adaptively select denoising parameters for different regions according to the gradient amplitude of SEM images and effectively solve the problem of global parameters not being applicable to noise in all regions of the image. Both simulation and experimental results demonstrate that the proposed method outperforms global denoising methods in terms of denoising performance. [ABSTRACT FROM AUTHOR]

This study aims to explore the variation patterns of catechin content under different green tea withering process conditions and to develop a generalized model. The influencing factors considered include initial moisture content (A), withering hot air temperature (B), withering hot air humidity (C), and withering hot air velocity (D). Employing Design-Expert software, an orthogonal experimental design was conducted to investigate the effects of these factors and their interactions on catechin content in tea. Additionally, scanning electron microscopy was used to observe the microstructure of the withered leaves. The response surface analysis revealed model significance (R2=0.9072), indicating that the quality model for catechins concerning the four influencing factors is highly significant, with a non-significant lack of fit, confirming the model's statistical validity. The interaction between withering hot air temperature (B) and velocity (D) had the most significant impact on catechin content, likely due to changes in catechin oxidase activity in fresh tea leaves within specific temperature and velocity ranges, which in turn affected catechin production. When A, B, C, and D were set at 84.61%, 25.27 °C, 65.62%, and 0.14 m/s respectively, the catechin content (mass fraction) reached an optimal value of 40.62%. The generalized model derived is: Catechin content = + 12.74 + 2.68 A − 1.70 B − 0.65 C − 2.71 D − 1.37AB + 1.38AC − 0.20AD − 1.11BC + 6.08BD − 1.35CD − 1.28 A2 − 1.54 B2 − 0.52 C2 − 1.08 D2. This model provides a theoretical basis for advancing key technologies in the development of green tea withering processes and equipment. [ABSTRACT FROM AUTHOR]

Abstract Background Resin-based pit and fissure sealants, used to prevent dental caries, can experience abrasive wear. This study aimed to assess the abrasive wear of experimental pit and fissure sealants (DIF) compared with the other commercial pit and fissure sealants by measuring surface roughness, volume loss, and ultrastructure after chewing simulation at different time points. Methods Specimens were divided into five groups (n = 10): Clinpro™(CP), Teethmate™ White (TW), Teethmate™ Natural (TN), experimental sealant (DIF), and Filtek™ Supreme Flowable Restorative (FC). They underwent chewing simulation with 120,000, 240,000, and 360,000 strokes. Surface roughness and volume loss were measured with a profilometer, and ultrastructures were assessed using scanning electron microscope (SEM). Results All specimens showed a significant increase in surface roughness after chewing simulation. FC had the highest roughness (p 0.05). All materials experienced significant volume loss. Sealant types and chewing cycles affected volume loss, with CP showing the highest and TW the lowest (p

The seven-spotted ladybug, Coccinella septempunctata (Coleoptera: Coccinellidae) L., is a polyphagous predatory species that feeds on many species of aphids and some soft-bodied insects in both larval and adult stages. For this reason, C. septempunctata L. (Coccinellidae) is very important in biological control. In this study, the egg structure and first larval period of C. septempunctata were examined using stereomicroscopy and scanning electron microscopy. C. septempunctata eggs are clear and oval, appearing elliptical dorsally and ventrally and slightly rounded at both ends. The first larvae that emerge from C. septempunctata eggs are dark brown and have 3 pairs of legs. The abdomen consists of 8 segments. In SEM photographs, star-shaped structures were observed on both sides of the strip on the dorsal surface of the thorax and abdomen of the larvae. Large stigma openings were found at equal intervals on the lateral of abdomen. The egg and larval structure of the invasive species C. septempunctata is described in detail.

Abstract Background This study aims to compare design, phase transformation behavior, and torsional resistance of the ProGlider (PG) and ProTaper ultimate slider (PUS) and to compare the performance of two files in the glide-path preparation of a double-curved artificial canal. Methods Scanning electron microscopy, micro-computed tomography, and differential scanning calorimetry were used to characterize the samples. A torsional resistance test was performed to obtain ultimate strength and distortion angle. Simulated glide-path preparation was conducted with a double-curved resin canal, and both PG and PUS were operated on by 300 and 400 rpms. Maximum screw-in force, torque generated during canal shaping, number of pecking strokes to reach the apex were compared between groups. After canal shaping centering ratio and alteration of files were assessed. Statistical analyses were performed using the Mann-Whitney U test, and the Kruskal-Wallis test with Bonferroni correction. A p value less than 0.05 was considered significant. Results While the PG had a square cross-section, the PUS had variable square and rhomboid cross-sections and alternating cutting-edge. PG and PUS have austenitic transformation starting and finishing temperatures of 24–25℃, and 57–59℃, respectively. Ultimate strength of PUS are superior to that of PG, whereas the distortion angle of PG is greater than that of PUS (p