Universal Microscope Research Articles

The Effect of Liner Placement under Bulk-Fill Resin Composite Restorations on Cuspal Deflection in Maxillary Premolar Teeth.

Purpose: This study investigated the cuspal deflection in premolar teeth restored with different bulk-fill resin composites with or without using a liner. Materials and Methods: 60 extracted human upper premolar teeth were used. The samples in this study were divided into three main groups (20 samples for each) according to the materials used; Each group was subdivided into two subgroups according to presence of liner. Standardized large MOD cavities were prepared. The distance between two reference points on cusp tips was measured before the restoration using a universal microscope. Then the teeth were restored with different bulk-fill resin composites (Filtek bulk fill, X-tra fil bulk fill and Activa Bioactive Restorative Material) with and without a liner (Activa Bioactive base/ liner). Second reading of cuspal deflection was measured 15 min after the completion of restorations. All samples were subjected to thermal cycling using thermal cycler machine. Then the third reading of cuspal deflection was measured. The data were statistically analyzed with Kolmogorov-Smirnov and Shapiro-Wilk tests. Results: no statistically significant difference was found between the mean cuspal deflection of the three composites and cuspal deflection without liner showed statistically significantly higher mean value than with liner. Conclusion: The placement of Activa Bioactive base/liner beneath the bulk-fill resin composite restorations decreased cuspal deflection.

Stereoscopic three-dimensional (3D) slit-lamp photography using a compact 3D digital camera.

We describe a novel method of stereoscopic 3D slit-lamp photography using a portable compact 3D digital camera. Thirteen eyes of 13 patients underwent slit-lamp photography using a Fujifilm 3D compact digital camera. We modified a universal smartphone microscope adapter to attach the camera to the slit-lamp. Photography was attempted on Zeiss and on HAAG-Streit slit-lamps. Success was defined as capturing a stereogram that consists of two simultaneous pictures, one from each slit-lamp ocular. Stereoscopic 3D slit-lamp photos could be captured in all 13 eyes in which they were attempted on Zeiss slit-lamps. Captured 3D media included external, eyelid, conjunctival, corneal, anterior chamber, lens, vitreous, and optic disc pathologies. Stereoscopic 3D photography could not be obtained using this Fujifilm 3D digital camera on Haag-Streit slit-lamps because of alignment incompatibility between the oculars of the slit-lamp and the camera. Digital stereoscopic 3D slit-lamp photography is feasible using a compact 3D digital camera and compatible slit-lamp design. Images obtained using this technique may be helpful in clinical education.

МИКРОАРХИТЕКТОНИКА ГОНАД САМОК КЛАРИЕВЫХ СОМОВ, ВЫРАЩЕННЫХ В ИСКУССТВЕННОЙ СРЕДЕ

The article presents the research results obtained by use of probiotic «Sporothermin» for the cultivation of females of African sharptooth catfish in an artificial environment. Sporothermin is a probiotic that is a mixture of Bacillus subtilis and Bacillus licheniformis, which provides an increase in the adaptive abilities of fish to the long-term action of various adverse factors, which is relevant when growing in an artificial environment. The histological structure of the gonads of female sharptooth catfish was analyzed using a research motorized universal microscope Axio Imager. M2 (Carl Zeiss, Germany). The results of our research have shown that in sharptooth catfish grown using the probiotic «Sporothermin», germ cells are observed, represented by oogonia and young oocytes of the protoplasmic growth period. Oocytes appear, that finished protoplasmic growth as well as oocytes that have completed trophoplasmic growth. At this stage, oocytes in the cytoplasm contain fat droplets that are part of the yolk grains, coloring from light yellow to orange with various shades. Female sharptooth catfish (Clarias gariepinus) of the control group, grown without the use of the probiotic «Sporothermin», have a violation of the synthesis of yolk granules, as well as edema of the follicular layer of the gonads, resorption of yolk grains and edema of the connective tissue egg-bearing plate, there is no striation of the radial layer, and deformation of the trophoplasmic oocyte is noted. In histological studies of the gonads of female sharptooth catfish, it was found that the use of the probiotic «Sporothermin» leads to a decrease in disorders in their microstructure, due to the strengthening of the membranes of the gonad cells.

Pathology of cells and tissues of the gastrointestinal tract of African catfish in high-tech industrial aquaculture

There is a possibility of developing a pathological process in the body of fish in the conditions of high-tech industrial aquaculture and at high planting densities, creating chronic stress. Histological studies allow early detection of the initial stages of possible pathology at the cellular level. The studies have shown that apparently healthy individuals of African catfish grown in recirculating aquaculture systems (RAS) revealed pathology of cells and tissues of the gastrointestinal tract. They had edema of the internal muscle layer of the stomach and intestines, detachment of the epithelial layer from the gastric mucosa, violation of the structural organization of gastric fields on histological sections. Thinning of intestinal villus, reduction of their length and branching, violation of their structure up to destruction were also revealed. The study of the tissues of the stomach and intestines was carried out using a research motorized universal microscope Axio Imager.M2 (Carl Zeiss, Germany). To correct the pathological process, the experimental group of fish received a “sporothermin” probiotic with feed, which belongs to the probiotics of the last generation. It is an antagonist of a wide range of pathogenic and opportunistic microbiota and is used as an alternative to antibiotics. The composition of “sporothermin” includes spore forms of bacteria Bacillus subtilis and Bacillus licheniformis, which in the gastrointestinal tract of fish turn into vegetative forms. Bacteria Bacillus subtilis and Bacillus licheniformis are not representatives of the intestinal microbiocenosis of the African catfish, but they regulate its structure by reducing the level of pathogenic and opportunistic microbiota. Pathology of cells and tissues of the gastrointestinal tract have been identified in the fish of the experimental group treated with the sporothermin probiotic.

Synthesis of poly(4, 4′‐biphenylene sulfonyl succinamide)‐polysulfone blend membranes for removal of toxic metal ions from water

ABSTRACTA novel polymer poly(4,4′‐biphenylene sulfonyl succinamide) (PBSS) was synthesized via polycondensation reaction. Succinyl chloride and 4‐aminophenyl sulfone were used as reactive monomers and anhydrous AlCl3 was used as a catalyst. Both polysulfone (PSf) and PBSS were dissolved in N‐methyl‐2‐pyrrolidone (NMP) at different compositions to obtain a homogeneous solution to fabricate PSf‐PBSS blend membranes. The structure of PBSS was characterized by ATR‐IR and 1H‐NMR spectroscopy. Thermal properties of PBSS were analyzed by TGA‐DTA. Mechanical properties and morphology of blend membranes were analyzed by universal testing machines and field emission scanning electron microscope, respectively. The hydrophilicity of blend membranes with respect to the concentration of PBSS was studied by contact angle and water uptake studies. Upon blending, the hydrophilicity of PSf‐PBSS membranes drastically increased due to the presence of large number of amide and sulfonyl groups in the matrix. The blend membranes exhibited significant increase in water flux from 100 L m−2 h to 650 L m−2 h−1, and rejection of 100% for Pb(II) and 80% for both Cd(II) and As(III) toxic heavy metal ions. The hydrophilic nature of CONH and inter and intramolecular hydrogen bonding among PBSS polymer chains dispersed within rigid PSf matrix imparts softness, amide and sulfonyl groups enhance interconnected porosity and hydrophilicity of blend membranes. Hence, PBSS may serve as a low‐cost novel polymeric additive for water purification and separation membrane applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48254.

Effect of Zeolite on Early Strength of Portland Cement Mortars

Portland cement consists essentially of compounds of lime mixed with silica and alumina whereas zeolite is a kind of minerals containing high content of reactive silica and alumina. Therefore, there is a probability to apply zeolite in cement mortar in order to develop mortar properties. The purpose of this research was to study and analyze the efficiency of zeolite addition on properties of cement mortar. X-ray diffraction (XRD), universal testing machine (UTM) and scanning electron microscope (SEM) were used to characterize for mortar specimens. Mechanical property test was compressive strength according to ASTM C109 and carried out on 5 x 5 x 5 cm3 cube specimens at 1, 7 and 28 curing days. In this research, cement mortars were prepared by mixing type I Portland cement, fly ash, sand and zeolite. Zeolite was varied as 0, 0.25, 0.50 and 0.75 wt.% to cement and w/b (water to binder ratio) was 0.48. The results presented that the compressive strength of mortar with small amount of zeolite was improved since 1day age obviously comparing to that of mortar without zeolite. It was confirmed that zeolite would help strengthening the cement mortars at early strength.

Effect of oral appliance on reproductive system of the male New-Zealand rabbit with obstructive sleep apnea-hypopnea syndrome

Objective: To observe the effect of the mandible advanced device on the reproductive system of the male New-Zealand rabbit with obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: Thirty male New-Zealand white rabbits were randomly divided into three groups (with 10 rabbits in each group): sleep apnea-hypopnea syndrome group (group OSAHS), mandible advanced device group (group MAD) and control group. On the basis of the OSAHS animal model, mandible advanced devices were used for group MAD animals. After intervention for 8 weeks (sleeping by dorsal position, 4-6 hours/d), the samples were gained from the animals under general anesthesia and observed under the transmission electron microscope (TEM) and the AX-80 universal microscope. The cauda epididymis was obtained to be observed the number, viability, motility and abnormal rate of spermatozoa. Results: Compared with the control group, the upper airway space, the saturation of blood oxygen, partial pressure of oxygen, pH, the number, viability rate and motility rate of spermatozoa in cauda epididymis of the group OSAHS were significant decreased (all P<0.05), and the partial pressure of carbon dioxide and the rate of teratospermia was significant increased (both P<0.05). But compared with the control group, these indexes mentioned above in the group MAD showed no statistical significance (all P>0.05). TEM and the light microscope showed that the status of spermatogenic cell, seminiferous tubule and spermatogenic epithelium was improved in the group MAD. The correlation analysis showed that the saturation of blood oxygen had a negative correlation with the rate of teratospermia (r=-0.614, P<0.001). Conclusion: The damage of spermatogenic cells and the decrease of the sperm quality caused by OSAHS in New-Zealand rabbits could be improved by the mandible advanced devices.

STUDY OF REPAROTIVNYH PROPERTIES OF CELLULAR STRUCTURES MADE OF TITANIUM IN THE EXPERIMENT

Aim. Using metallography to determine the architectonics wire mesh implant made by the method of stereolithography. In the experiment to compare the structure of different materials and their degree of fixation in the bone (wire mesh of titanium, Plekon and porous titanium). Material and methods. The paper presents the simulation results, fabrication of the implants, which perform cellular structure (cell Wigner-Seitz). When applied three-dimensional modeling system, and in the production – technology stereolithography. The results of the research porous implants from titanium using a universal metallographic microscope Altami MET-5D by increasing from 50Х up to 200X. Results. It was found that the surface of the walls are not smooth, but bumpy due to the microscopic depressions and protrusions of the metal. The cone micro canals are clearly seen, scattered that some of them are cross-cutting, others end blindly. In the microchannel jumpers implant founded sprouted connective tissue filling all the space, the density is not inferior to the connective tissue located in the cells. Established that the fourth degree of fixation of mesh implants was identified in 55.6% of the animals of porous Placona-M - y 28.6% of the subjects, of porous titanium – 41,6%, indicating a high reparative properties of cellular structures. Conclusions. The Jumper forming cells of the implant structure have a structure of porous titanium with reparative properties. IV the degree of fixation of mesh implants was identified in 55.6% of animals, indicating a high reparative properties of cellular structures.

Investigation of injection molding parameters on the uniformity of porous array of polymer microfluidic chip

The uniformity of the porous array seriously affects the performance of the injection-molded parts. In this study, a uniform hole array chip constituted by 384 holes whose radiuses are 1.30 mm is fabricated by precision injection molding technology. To capture the relevance between the uniform dimension of the porous array and the injection molding process parameters, single factor experiment was adopted. Besides, the condensed state of the hole array was studied to give a further explanation of the inner relationship between the hole array and the most sensitive injection process. As for the measurement, the diameter of the hole which next to the gate and away from the gate was investigated by means of universal tool-measuring microscope, and the standard deviation of the hole diameter was chosen to estimate the uniformity of the hole array. Furthermore, the crystal state and interface state were characterized by polarized light microscopy (PLM), used to explain why the difference of those holes appeared. The results reveal that the impact of process parameters on the uniformity of the hole array was ranked as follows: melt temperature, cooling time, mold temperature, injection pressure, injection speed and packing pressure. Besides, the analysis of the condensed state on different melt temperature indicates that the larger grain size is less favorable to the uniform molding, as the melt temperature increases, the difference of cortical thickness between the dynamic template and fixed template sides decreases, product uniformity is improved.

Electrical and Mechanical Properties of Acrylonitrile Butadiene Styrene/Graphene Platelet Nanocomposite

Acrylonitrile butadiene styrene (ABS) is a desirable engineering plastic due to its outstanding properties including good processing characteristic, good mechanical properties, chemical resistance and is relatively low cost. However, having an insulating behaviour restricts its application in electrical and electronic products. With the aim to increase the conductivity of ABS, a conducting material, in this case, graphene was incorporated. Mixtures of ABS and graphene were prepared by varying the weight of graphene and their electrical and mechanical properties were measured using Electrochemical Impedance Spectroscopy, (EIS), universal testing machine, pendulum impact and field emission scanning electron microscope (FESEM). From the results, improvement of conductivity and mechanical (tensile and flexural strength) properties of ABS-graphene composite is shown by higher amount of graphene. These enhanced properties can be related to good dispersion and intimate interaction of graphene platelet and ABS matrix as confirmed by electron microscopy image

Spectroscopic, Mechanical, and Thermal Characterization of Native and Modified Nigerian Coir Fibers

ABSTRACTCoir fibers native to Nigeria and their modified forms viz: acetylated coir, oxidized coir, and mercerated coir have been characterized by spectroscopic, thermal, mechanical, and microscopic techniques. The CP/MAS 13C NMR spectra revealed that the modification of these fibers did not affect the cellulose type (C-1) and that the fibers are moderately crystalline. All the fibers can be said to be thermally stable until 200°C and based on the cumulative mass loss at 400°C modification of the coir fibers promoted an increase in thermal stability in the order mercerated coir > oxidized coir > acetylated coir > native coir. The mechanical and morphological properties of the native and modified Nigerian coir were also investigated using universal testing machine and scanning electron microscope, respectively, and the results are discussed.

Replication of large scale micro pillar array with different diameters by micro injection molding

The capillary force is always used as the driving force of microfluidic chips. In this study, the capillary force of blood smart diagnostic microfluidic chip which fabricated by micro-injection molding (μ-IM) is offered by the structure of micro pillar array. And the detection effect of blood smart diagnostic microfluidic chips is affected by the replication and height distribution of large scale micro pillar array. So the effect of process parameters on the micro-structure and the height distribution of micro pillar is studied. The mold design is also an important factor affecting micro parts properties. In this study, a steel mold insert with almost 15,500 micro blind cavities was fabricated by milling, electrical discharge machine and Femtosecond Laser process. Polymethyl methacrylate -Polystyrene copolymer (SMMA NAS 30) was used as the molding material. The single factor trail and orthogonal experiment approach were adopted to investigate the effect of several process parameters and the significant effect factors affecting the replication of micro pillar. And the height distribution of micro pillar array was investigated by scanning electron microscope (SEM) and universal tool-measuring microscope to measure the replication quality. The results reveal that the replication of micro pillar is sensitive to the flow direction of the polymer melt. The height of micro pillar increases with the increase of mold temperature and injection speed. Moreover, the height distribution of micro pillar along and against flow direction was tightly related to the thermomechanical history of material during the molding process.

Workflow for High-content, Individual Cell Quantification of Fluorescent Markers from Universal Microscope Data, Supported by Open Source Software

Advances in understanding the control mechanisms governing the behavior of cells in adherent mammalian tissue culture models are becoming increasingly dependent on modes of single-cell analysis. Methods which deliver composite data reflecting the mean values of biomarkers from cell populations risk losing subpopulation dynamics that reflect the heterogeneity of the studied biological system. In keeping with this, traditional approaches are being replaced by, or supported with, more sophisticated forms of cellular assay developed to allow assessment by high-content microscopy. These assays potentially generate large numbers of images of fluorescent biomarkers, which enabled by accompanying proprietary software packages, allows for multi-parametric measurements per cell. However, the relatively high capital costs and overspecialization of many of these devices have prevented their accessibility to many investigators. Described here is a universally applicable workflow for the quantification of multiple fluorescent marker intensities from specific subcellular regions of individual cells suitable for use with images from most fluorescent microscopes. Key to this workflow is the implementation of the freely available Cell Profiler software1 to distinguish individual cells in these images, segment them into defined subcellular regions and deliver fluorescence marker intensity values specific to these regions. The extraction of individual cell intensity values from image data is the central purpose of this workflow and will be illustrated with the analysis of control data from a siRNA screen for G1 checkpoint regulators in adherent human cells. However, the workflow presented here can be applied to analysis of data from other means of cell perturbation (e.g., compound screens) and other forms of fluorescence based cellular markers and thus should be useful for a wide range of laboratories.

Workflow for high-content, individual cell quantification of fluorescent markers from universal microscope data, supported by open source software.

Advances in understanding the control mechanisms governing the behavior of cells in adherent mammalian tissue culture models are becoming increasingly dependent on modes of single-cell analysis. Methods which deliver composite data reflecting the mean values of biomarkers from cell populations risk losing subpopulation dynamics that reflect the heterogeneity of the studied biological system. In keeping with this, traditional approaches are being replaced by, or supported with, more sophisticated forms of cellular assay developed to allow assessment by high-content microscopy. These assays potentially generate large numbers of images of fluorescent biomarkers, which enabled by accompanying proprietary software packages, allows for multi-parametric measurements per cell. However, the relatively high capital costs and overspecialization of many of these devices have prevented their accessibility to many investigators.Described here is a universally applicable workflow for the quantification of multiple fluorescent marker intensities from specific subcellular regions of individual cells suitable for use with images from most fluorescent microscopes. Key to this workflow is the implementation of the freely available Cell Profiler software1 to distinguish individual cells in these images, segment them into defined subcellular regions and deliver fluorescence marker intensity values specific to these regions. The extraction of individual cell intensity values from image data is the central purpose of this workflow and will be illustrated with the analysis of control data from a siRNA screen for G1 checkpoint regulators in adherent human cells. However, the workflow presented here can be applied to analysis of data from other means of cell perturbation (e.g., compound screens) and other forms of fluorescence based cellular markers and thus should be useful for a wide range of laboratories.

Effect of Ultrasonic/Electromagnetic Energy-Field on Structure Andproperties of Cast-Rolled 3003 Aluminum Alloy Strips

The plates under the compound energy field and the general ones were prepared by introducing ultrasonic and electromagnetic field at the key part of the cast-rolling area, and then the final aluminum strips with thickness of 0.27 mm were prepared through cold rolling and annealing. The microstructures and properties were investigated by optical microscope (OM), static/dynamic universal testing machine and scanning electron microscope (SEM). The results show that by applying compound energy-field, grains are significantly refined and the mechanical properties are improved. Compared to the general cast-rolling strips, the ultimate tensile strength, yield strength and elongation of compound energy-field aluminum strips are improved by 32.93%, 38.91% and 6.25%, respectively.

Nanoindentation and microstructure of hybrid treated of AISI 316L at low temperature

This paper presents the characterisation of hybrid treated layer on austenitic AISI 316L stainless steels using field emission scanning electron microscope (FESEM), universal scanning probe microscope (USPM) and nanoindentation after low temperature thermochemical treatments. By using these methods, the improvement of its mechanical properties due to the diffusion of carbon and nitrogen at low temperature treatments were confirmed. The hybrid treated layer has shown increment of hardness and elastic modulus compared to untreated sample. Based on the investigation, it is shown that all treated samples have enhanced E/H ratio which demonstrated the decreasing tendency to plastic deformation and reduced the disparity of properties, while keeping deformation within the elastic range.

Thread Measurement Algorithm Research and Software Development

The quality of thread will directly affect the reliability of mechanical system, and the accuracy grade of geometric parameters is the judgment standard to thread quality. Thus, its particularly important to detect the geometric parameters of thread. Its a pretty mature and widely used method to measure thread parameters with universal tool-measuring microscope, but it has many shortcomings, such as tedious operation, low efficiency and the reading error. In view of the above shortcomings, the paper does some simple refits to the existing 19JA universal tool-measuring microscope. In order to improve reading speed and accuracy, the grating rulers are installed on the operating platform in two directions. CCD camera is used to get external thread image instead of human eyes and the eyepiece, which is a non-contact measurement method. A software that based on MFC of VC + + 6.0 is written, which can deal with the thread image and get the thread parameters. The experimental results show that the method can not only effectively improve the measurement efficiency but also guarantee the accuracy of measurement.

Effects of Different Parameters on Delamination Factor of Glass Fiber Reinforced Plastic (GFRP)

The experimental investigations of the delamination factor of glass fiber reinforced plastic at different cutting parameters are reported in this study. This paper has involved the determination of different factors affecting the hole quality and cause of delamination in a glass fiber reinforced plastic. The various process parameters like different twist drill bits of different materails, different point angle at different speed, feed rate have been taken. The thrust forces and torque values were measured using piezoelectric dynamometer. Mathematical model has been developed for different machining conditions using Minitab software with help of Taguchi design to plan the experiments. The Universal microscope has been used which determines delaminated diameter in GFRP specimens. The finite element method has been applied by using Ansys11.0 software which helped to find out delaminated diameter. It was experimentally observed that for the tungsten carbide and M50 drill bits, the thrust force and torque significant increases on increasing the point angle and feed rate.

Effect of VC and C Addition on Mechanical Properties and Microstructures of WC-Co Hardmetals Processed in Nitrogen-Based Atmosphere

The WC-Co, WC-Co-VC and WC-Co-C samples are fabricated using powder metallurgy technique. The mixed powder is compacted under the pressure of 625 MPa, cold-isostatic pressed at 200 MPa and sintered at temperature in the range of 1350 – 1450°C nitrogen-based atmosphere. The mechanical properties of the samples are analyzed using Vicker’s microhardness tester, universal tensile machine and scanning electron microscope. Test results reveal that WC-Co-C sample has better mechanical properties as compared to WC-Co and WC-Co-VC due to the formation of homogeneous and dense structure.

Forward and Reverse Driving Noise Analysis of HDM Based on Sound Signal

As there are the errors during the manufacturing and assembling of horizontal driving machine (HDM). The exceptional knocking noise is generated during some products running. The failure rate of product quality is rising as well. The forward and reverse driving noise of HDM was tested and analyzed. The pictures was collected by universal tool microscope. The results show that hot runner is not smooth enough to reduce transferring pressure and increase the shrinkage of worm pouring gate, which lead to slight conical degree of product and pitch deviation at worm pouring gate. As the pitch makes worm inset slightly worm gear when clockwise rotating, the noise and vibration was produced consequently in this direction. The proposals were given, such as strengthening the maintenance of hot runners, controlling and inspecting product conical degree, and optimizing HDM mould and increasing its accuracy, and so on.