3D Video Microscope Research Articles

Effects of surface micro-structure of fruits on droplet evaporation process: Peach and apple cases

Droplet evaporation at the fruit surface is a common issue related to the efficiency of pesticide spraying as well as freshness preservation. Many works have been carried out demonstrating the impacts of substrate characteristics on the droplet profile, wettability, and evaporation properties in the field of industrial applications. However, the influences of specific fruit skin on the droplet evaporation rate have been rarely studied. Thus, the present works aim to explore the effects of different surface micro-structures of fruits on the droplet properties experimentally through the 3D video microscope, drop shape analyzer, and infrared camera. Apple and peach have been selected respectively as two examples of waxy and hairy skins, and comparisons have been made focusing on the surface roughness, droplet profile including contact angle, contact area, and contact diameter, evaporation rate, and temperature distribution of droplets with a constant initial volume of 2ul. The results show that the differences in micro-structure for apple and peach surfaces have significant impacts on the droplet evaporation performance. A larger evaporation rate has been found for apple skin with three distinct phases including spreading, pinning, and shrinkage periods. However, the pinning phenomenon tends to be broken for the peach case due to the unique properties of super-hydrophobic surfaces and the existence of fluff. Moreover, lower values of temperature at the top center of a droplet can be always observed during the whole evaporating process with peak values of temperature gradient near the triple-phase region.

CS-5 A case of anaplastic pleomorphic xanthoastrocytoma in the pineal region

Tumors in the pineal gland are rare tumors that account for about 0.3% of all brain tumors and have various histological types of tumors develop with germinoma, pineocytoma, and pineoblastoma in that order. On the other hand, pleomorphic xanthoastrocytoma (PXA) is a rare tumor of less than 0.2% and frequently occurs in supratentorial cerebral surface of children and young adults.A case was a 61-year-old man whose pineal tumor was found due to visual disturbance. MRI showed a 23 mm-sized lesion with cysts and inhomogeneous enhancement in the pineal gland. Partial calcification was observed, but there was no non-communicating hydrocephalus, and no increase in HCG-β and AFP with blood sampling. A midline suboccipital craniotomy was performed in the sitting position, a head-up surgery was performed using a 4K / 3D video microscope system (ORBEYE exoscope, Olympus) by the infratentorial supracerebellar approach (ITSCA). The bridging veins and precentral cerebellar vein were dissected to expose the posterior surface of the tumor, and internal decompression was performed. For the complication of air embolism, artificial cerebrospinal fluid was sprayed, and the bilateral internal jugular veins were compressed to confirm the inflow point. There was strong adhesion to the Rt vein of Rosenthal, and the site was removed intracapsularly. Finally, subtotal resection was performed with remaining the upper part of the tumor, a blind lesion behind the Vein of Galen. Vertical gaze palsy occurred after this operation, but it gradually improved over time. Tumor showed pathologically remarkable polymorphism, poor microvascular proliferation and necrosis, but mitotic figures 4–5 / 10HPF, MIB-1 index 10%, GFAP positive, no BRAF V600E mutation. There are few reports of PXA occurring in the pineal gland, and this case is the sixth case. It is also the first report for pineal tumors using ORBEYE through ITSCA in the sitting position.

Students' perception of 3D video microscope use in preclinical fixed prosthodontics: A comparative study.

The purpose of this study was to determine how students perceived the use of a 3D video microscope (3D VM), in comparison to conventional methods, for providing instruction on fixed prosthodontics procedures and issuing feedback on student performance. From May until December of 2020, University at Buffalo School of Dental Medicine's second-year students were introduced to fixed prosthodontics. During May and June, a 3D VM was used to live-stream psychomotor skill demonstrations via a web-based software. After each procedure, students were asked to complete a short survey regarding their experience with the training. From August until December 2020, students received feedback via: 1. The conventional method, in which faculty use magnification loupes to assess student's perfromance. 2. A 3D VM. Irrespective of the method used, feedback was given following the same defined rubrics. At the conclusion of the semester, students completed a survey comparing their experiences in receiving instruction and feedback. The data were gathered and analyzed descriptively. The chi-square test (α=.05) was used to gauge if students' gender had an impact on their perception of feedback methods. More than 94% of students participated in the surveys. The majority of students had a positive reaction toward the use of the 3D VM for live web-based training. In regard to receiving feedback, 63% opined that the 3D VM was more effective than the conventional method. Additionally, 80% of students felt that the 3D VM was effective in maintaining physical distance during skill evaluations. This study examined the use of a 3D VM for teaching psychomotor skills and providing student feedback and compared it to the conventional method. It was found that the use of the 3D VM was perceived positively by students. Gender had no significant impact on students' attitudes toward the teaching and feedback methods.

Construction of photonic crystal structural colors on white polyester fabrics

Recently, it has become a novel technology to obtain structural color on fabric and has become a research hotspot in the textile field. However, the researchers still use fabric dyed with black dye as substrates, which does not meet the requirements of clean dyeing. In this work, we aimed at changing the status quo that most structural color fabrics are designed based on black fabrics. SiO2@PDA microspheres with inorganic microspheres SiO2 as the core and black polydopamine as the shell were successfully prepared. White polyester fabrics were taken as substrates to constructing SiO2@PDA photonic crystal structural colors via vertical deposition self-assembly method (VDSM). The morphology and composition of SiO2@PDA microspheres were investigated. The morphology and optical properties of the resultant structural color fabrics were characterized by FESEM and 3D video microscope. The results showed that SiO2@PDA microspheres have good sphericity, monodispersity, exhibiting and with a distinct core-shell structure formed an ordered colloidal array with vacancies and defects on the polyester fabrics by VSDM, which appeared bright, vivid and low angle-dependent structural colors under the visible light. The different structural colors can be obtained by adjusting the size of the SiO2@PDA microspheres and viewing angle, following the Bragg diffraction law. Notably, SiO2@PDA microspheres with black polydopamine shells have the functionality of absorbing incoherently scattered light and can be used to obtain structural colors directly on white fabric substrates, which significantly simplified the preparation process of structural color fabrics.

4K 3-dimensional video microscope system (orbeye) for transsphenoidal pituitary surgery

BackgroundIn previous reports on experiences with an exoscope, this new technology was not found to be applicable for transsphenoidal pituitary surgery. As a specialized center for pituitary surgery, we were using a 4K 3D video microscope (Orbeye, Olympus) to evaluate the system for its use in transsphenoidal pituitary surgery in comparison to conventional microscopy.MethodWe report on 296 cases performed with the Orbeye at a single institution. An observational study was conducted with standardized subjective evaluation by the surgeons after each procedure. An objective measurement was added to compare the exoscopic and microscopic methods, involving surgery time and the initial postoperative remission rate in matched cohorts.ResultsThe patients presented with a wide range of pathologies. No serious events or minor complications occurred based on the usage of the 4K 3D exoscope. There was no need for switching back to the microscope in any of the cases. Compared to our microsurgically operated collective, there was no significant difference regarding duration of surgery, complications, or extent of resection. The surgeons rated the Orbeye beneficial in regard to instrument size, positioning, surgeon’s ergonomics, learning curve, image resolution, and high magnification.ConclusionsThe Orbeye exoscope presents with optical and digital zoom options as well as a 4K image resolution and 3D visualization resulting in better depth perception and flexibility in comparison to the microscope. Split screen mode offers the complementary benefit of the endoscope which may increase the possibilities of lateral view but has to be evaluated in comparison to endoscopic transsphenoidal procedures in the next step.

Investigation on Speed-Load Sensitivity to Tribological Properties of Copper Metal Matrix Composites for Braking Application

A sensitivity analysis of braking speed and normal load on tribological properties of copper metal matrix composites (Cu-MMCs) was investigated using a subscale dynamometer. The morphologies of the worn surface and subsurface were observed by a scanning electron microscope and 3D video microscope. The results indicated that temperatures on the Cu-MMC surface increased with increasing the braking speed and normal load. The average coefficient of friction gradually decreased as the braking speed or normal load increased, and a slight decrease in the wear rate with increasing the braking speed up to 17 m/s after which a clear increasing trend was observed. As the normal load increased from 612 N to 1836 N, the wear rate decreased firstly and then promptly decreased. The transition in wear mechanism of Cu-MMC significantly depended on braking speed and normal load.

Experimental Study on the Mechanical Performance of Grouted Specimen with Composite Ultrafine Cement Grouts

An experimental investigation was conducted in order to understand properties of grouts and grouted specimens. Three different cement types, i.e., composite ultrafine cement (CUC) that was independently developed, ultrafine cement (UC), and Portland cement (PC) were injected into broken red sandstone specimens on the basis of a self-designed grouting test equipment. After the grouting test, the effects on the mechanical behavior of grouted specimens were studied using an uniaxial compression test, macroscopic failure analysis and mesostructure analysis, as well as a comparison of the mechanical and structural properties of three types of grouted specimens was presented. The test results show that the compressive strength of grouted specimens improved in comparison to the rock residual strength, and the compressive strength of PC, UC and CUC grouted specimens increased by 23.0%, 59.6% and 101.5%, respectively. The failure modes of all grouted specimens were brittle failure, but only the CUC grouted specimen was failed along the new failure surfaces, indicating that CUC grouts can better bond the original cracks. The mesostructure characteristics obtained through the Digital 3D Video Microscope reveal the superior filling effect of the CUC grouts as well as verifying the macroscopic mechanical behavior.

Growth mechanism of micro-arc oxidation film on 6061 aluminum alloy

The 6061 aluminum alloy was disposed using bipolar pulse micro-arc oxidation power supply in Na2SiO3-CH3COONa-Na5P3O10 electrolyte system, where the surface spark discharge of aluminum alloy during micro-arc oxidation was observed by long distance working microscope, and the micro-structure of molten pool in micro-arc oxidation film were studied by 3D video microscope, SEM, XRD, combined with film/substrate separation technology and layer by layer thinning technique. Also, the mechanism of micro-arc oxidation breakdown and discharge of aluminum alloy was investigated thoroughly. The results showed that duration time of spark discharge increased with the progress of micro-arc oxidation reaction, which was 67 ms when oxidation reaction lasted 1 min, however it reached 532 ms when reaction lasted 90 min. With increase of oxide film thickness, the size of spark and weld pool increased, where the size of spark was exponentially related to thickness of film, and size of molten pool was linear to the film thickness, while two sizes were approximately equal. The profile of molten pool was trumped-like shape, and part of the pool was connected with each other in the oxide film, leading to a formation of three-dimensional network structure. At the bottom of oxide film, there were discharge micropores with a diameter of ∼150–200 nm, and α-Al2O3 phase content in the film increased from the surface to bottom. Micro-arc discharge occurred in ‘interlock’ form at bottom of the oxide film, forming ‘fire flower clusters’, which melted and vaporized around metals, such that spraying concurred, while new oxides was formed at the surface and bottom of oxide film, thus making the oxide film thicker.

Study on the stability of the photonic crystals under different application environments and the possible mechanisms

P(St-MAA) and SiO2 photonic crystals on polyester fabrics were put in the different application environments such as water, oil, acid, alkali, high temperature, and ultraviolet radiation. The related changes of the morphology and the structural colors were characterized by 3D video microscope and field-emission scanning electron microscopy (FESEM) and the possible mechanisms were deeply investigated. It is found that aqueous medium have little influence on P(St-MAA) and SiO2 photonic crystals, however, oil medium restrains the photonic crystals from regaining the original structure. Even though in aqueous medium, strong acid and alkali conditions could easily destroy the photonic crystal structure to great extent even degrade the microspheres. Different from the good stability of P(St-MAA) and SiO2 photonic crystals at conventional high temperatures, under the ultraviolet irradiation P(St-MAA) are severely destroyed due to the drastic thermal depolymerization, but SiO2 photonic crystals keep favorable morphology and structural color.

Interface–gravity joint self-assembly behaviors of P(St-MAA) colloidal microspheres on polyester fabric substrates

P(St-MAA) photonic crystals of face-centered cubic structure in bright structural colors were fabricated on polyester fabrics by interface–gravity joint self-assembly. The elaborate self-assembly process was investigated by digital camera, 3D video microscope, and field emission scanning electron microscopy, and the possible interface–gravity joint self-assembly and crystallization mechanisms of the colloidal microspheres on polyester fabric substrates were proposed. It was confirmed that the interface–gravity joint self-assembly on polyester fabrics was composed of two different self-assembly processes simultaneously, in which the rate of interfacial self-assembly driven by capillary force and convection effect is much faster than the gravitational sedimentation self-assembly under the gravity. With the evaporation of solvent, an ordered colloidal crystal structure was gradually formed in the interfacial self-assembly on the air–liquid interface with a disorder-to-order transition during crystallization stage and covered on the polyester fabric substrate filled with colloidal microspheres in gaps between yarns and fibers during gravitational sedimentation self-assembly.

Clinical observation of the tooth surface during air-drying of self-etching primer under 3D video microscope

To clarify the optimal amount of air-drying time, this study measured the time taken to remove residual excess solvent from self-etching primer under observation with a 3D video microscope. One hundred teeth were restored with direct resin composite restorations (16 upper anterior teeth, three lower anterior teeth, 14 upper premolars, 13 lower premolars, 16 upper molars, and 38 lower molars) under observation with a 3D video microscope. In all restorations, Clearfil SE Protect was used for bonding of the resin composite under controlled environmental conditions (intra-oral temperature and humidity) using an intra-oral vacuum device. The duration of air-drying needed to evaporate the residual solvent from the self-etching primer solution was simultaneously measured. The data obtained were statistically evaluated by one-way ANOVA and Tukey’s HSD multiple comparisons (p < 0.05). The duration for complete air-drying of the 100 cases was 40.9 ± 18.7 s. The air-drying durations in lower molar and upper anterior restorations were 48.1 ± 21.7 and 27.3 ± 14.6 s, respectively, with a statistically significant difference (p = 0.002). This study revealed that a greater air-drying duration was needed to evaporate solvent from the self-etching primer than routine air-drying in the clinical situation. It also indicated that a greater air-drying duration was required for posterior cavities than for anterior cavities.

The vertical deposition self-assembly process and the formation mechanism of poly(styrene-co-methacrylic acid) photonic crystals on polyester fabrics

Three-dimensional (3D) photonic crystals with structural colors were successfully fabricated on soft polyester fabrics through the vertical deposition self-assembly of monodispersed poly(styrene-co-methacrylic acid) (P(St-MAA)) colloidal microspheres. The elaborate process was investigated by digital camera, 3D video microscope, and field emission scanning electron microscopy, and the formation mechanism and the self-assembly mode of photonic crystal on the fabrics were proposed. It was confirmed that during the evaporation of the colloidal dispersion medium, the surface of the dispersion moved down slowly, and the photonic crystal structure was deposited gradually onto the fabrics due to two effects of capillary force, one being from the meniscus between the P(St-MAA) colloidal microspheres and the vertical polyester fabric substrate, and another from the liquid bridges between adjacent P(St-MAA) colloidal microspheres. The array of colloidal microspheres underwent a disorder-to-order transition during the formation stage, generating a series of varying structural colors in the process. Different from those on solid nonporous substrates, the vertical deposition process firstly occurred in the gaps of fibers, then in the fiber surfaces, and eventually formed the ordered photonic crystal structure on polyester fabric substrates.

Antifouling Performance of Surface Microtopographies Based on Sea Star &lt;i&gt;Luidia quinaria&lt;/i&gt;

The surface microtopographies of the sea starLuidia quinariawere investigated and measured by 3D video microscope and scanning electron microscope. The antifouling effectiveness of biomimetic microtopographies based on sea star surface was evaluated using diatoms.

Reconstruction and Analysis of Wear Topography of PcBN Abrasive Grain

This paper mainly deals with the reconstruction and fractal analysis of wear topography of brazed polycrystalline cubic boron nitride (PcBN) grain in grinding process. On the basis of fractal analysis, the uncertainty in shape and complexity in wear mechanism are analyzed by means of the construction of micro fracture of PcBN grain after producing the brazed abrasive tool with PcBN grains and carrying out grinding test. The main results are summarized as follows: (1) Actual behavior of self-sharpening phenomenon due to micro fracture in the grinding process can be grasped and reconstructed using SEM and 3D video microscope. The reconstruction model can clearly express the complicated wear features and characteristics of the grain. (2) The fractal dimension can relate the performance of PcBN grain to its micro fracture, and then the self-sharpening phenomenon due to micro fracture can be evaluated quantitatively on the basis of fractal analysis.

The Preliminary Study on Antifouling Mechanism of Shark Skin

Biofouling, which is the result of marine organisms settling, attaching, and growing on submerged marine surfaces, is a usually-seeing phenomenon for the ocean-going ships and submarines. And, it can decrease the range, speed, and maneuverability of these vessels and increase the fuel consumption. Contrarily, the sharks remain largely free of bioadhesion despite spending their entire lives submerged. The sharks have placoid scales, which consist of rectangular base embedded in the skin with tiny spines that poke up from the surface. It is found that this special structure can make great deal of function for antifouling. In our report, parallel works for antifouling mechanisms were motivated by Triakidae shark feeding, observations on shark skin, and the experiments of benthic diatoms adhesion and Mytilus edulis byssus attachment. And, the optical configurations were acquired by using 3D video microscope and environment scanning electron microscope (ESEM). The results showed that, the benthic diatoms adhesion on the naked skin of living sharks was obviously fewer than the dead ones, and could not be found on the surface of placoid scales. As the time progressed, the rate of Mytilus edulis byssus attachment reduced gradually. It was thought that, the water turbulent boundary on the surface was changed greatly and innumerable minimal vortex was generated when the water flow on the shark skin. The strong exchange of momentum in a turbulent boundary layer would produce high-speed lumps approaching the surface, which could develop strong shear stress. Benthic diatoms and mussel could not attached firmly or be cleared easily when the shear stress became stronger than the adhesion power of these organisms. After finding the real working mechanism of antifouling for sharks, it could be used to direct the progresses of synthesizing biomimetic coatings or materials with antifouling performance in the future.