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Malaria is a disease that affects millions of people worldwide with a consistent mortality rate. The light microscope examination is the gold standard for detecting infection by malaria parasites. Still, it is limited by long timescales and requires a high level of expertise from pathologists. Early diagnosis of this disease is necessary to achieve timely and effective treatment, which avoids tragic consequences, thus leading to the development of computer-aided diagnosis systems based on artificial intelligence (AI) for the detection and classification of blood cells infected with the malaria parasite in blood smear images. Such systems involve an articulated pipeline, culminating in the use of machine learning and deep learning approaches, the main branches of AI. Here, we present a systematic literature review of recent research on the use of automated algorithms to identify and classify malaria parasites in blood smear images. Based on the PRISMA 2020 criteria, a search was conducted using several electronic databases including PubMed, Scopus, and arXiv by applying inclusion/exclusion filters. From the 606 initial records identified, 135 eligible studies were selected and analyzed. Many promising results were achieved, and some mobile and web applications were developed to address resource and expertise limitations in developing countries. [ABSTRACT FROM AUTHOR]

Chloroquine (CQ) has been a good treatment for antimalarial mainstay for several decades; additionally discovered, it has a significant therapeutic impact on some instances of fungal inhibition. This study focused on the effect of novel CQ compounds on the activity of two different species of fungi, Aspergillus niger and Aspergillus falves. The activity of each CQ derivative was monitored using Nuclear magnetic resonance spectroscopy (NMR), minimal inhibitory concentration and physical parameters such as optical microscopy, UV/visible absorbance and optical band gap. NMR indicated the conjugation between the substrate and amino acid. The optical microscopic images indicated homogeneously distributed and uniform density distribution of CQ-derivative particles on the glass substrates. The samples' presented absorption peaks at 203, 207 and 220 nm wavelengths, suggesting the important electronic transition with reducing the indirect bandgap from 4.1 eV to 3.95 eV. These compounds have the best antifungal growth inhibitory properties and excellent features, indicating cosmetics use. [ABSTRACT FROM AUTHOR]

There is an increasing demand to improve battery safety and performance as part of the global push to convert the small electronics and transportation sector to infrastructures based on electricity. This work follows the deposition of lithium metal in anode‐less conditions by an operando optical microscope using a transparent indium tin oxide‐polyethylene terephthalate (ITO‐PET) window as the current collector in a readily‐available electrochemical set‐up. The mechanism of Li metal nucleation strongly depends on the selected current densities (C/40 and 2C). After the deposition of the solid electrolyte interface (SEI), Li nucleates from mossy to needle morphology. Moreover, layer‐by‐layer growth of dead Li in voids is monitored by following its accumulation upon cycling. Dead Li deposits in residual hollow structures, especially when high current densities are applied. These optical observations are coupled with computer vision analyses to evaluate the average size of the Li deposits: smaller Li nuclei plate when high C‐rate is applied. The results here described provide insights into a new electrochemical cell concept that enables to elucidate the influence of spatial inhomogeneities of the lithophilic ITO‐PET surface on the mechanism of Li nucleation and plating. [ABSTRACT FROM AUTHOR]

Quantifying the response of marine mussel plaque attachment to wet surfaces remains a significant challenge to a mechanistic understanding of plaque adhesion. Here, we develop a novel, customized microscope system, combined with two-dimensional in situ digital image correlation (DIC), to quantify the in-plane deformation of a deformable substrate that interacts with a mussel plaque under directional tension. By examining the strain field within the substrate, we acquired an understanding of the mechanism by which in-plane traction forces are transmitted from the mussel plaque to the underlying substrate. Finite-element (FE) models were developed to assist in the interpretation of the experimental measurement. Our study revealed a synergistic effect of pulling angle and substrate stiffness on plaque detachment, with mussel plaques anchoring to a 'stiff' substrate at small pulling angles, i.e. natural anchoring angles, having mechanical advantages with higher load-bearing capacity and less plaque deformation. We identify two distinct failure modes, i.e. shear-traction-governed failure (STGF) and normal-traction-governed failure (NTGF). It was found that increasing the stiffness of the substrate or reducing the pulling angle results in a change of the failure mode from NTGF to STGF. Our findings offer new insights into the mechanistic understanding of mussel plaque–substrate interaction, providing a plaque-inspired strategy to develop high-performance and artificial wet adhesion. [ABSTRACT FROM AUTHOR]

The resolution of an optical microscope is determined by the overall point spread function of the system. When examining structures significantly smaller than the wavelength of light, the contribution of the background or surrounding environment can profoundly affect the point spread function. This research delves into the impact of reflective planar substrate structures on the system's resolution. We establish a comprehensive forward imaging model for a reflection-type confocal laser scanning optical microscope, incorporating vector field manipulation to image densely packed nanoparticle clusters. Both theoretical and experimental findings indicate that the substrate causes an interference effect between the background field and the scattered field from the nanoparticles, markedly enhancing the overall spatial resolution. The integration of vector field manipulation with an interferometric scattering approach results in superior spatial resolution for imaging isolated particles and densely distributed nanoscale particle clusters even with deep subwavelength gaps as small as 20 nm between them. However, the method still struggles to resolve nanoparticles positioned directly next to each other without any gap, necessitating further work to enhance the resolving ability. This may involve techniques like deconvolution or machine learning-based post-processing methods. [ABSTRACT FROM AUTHOR]

Defocus blurring imaging seriously affects the observation accuracy and application range of optical microscopes, and the blurring kernel function is a key parameter for high-resolution image restoration. However, its solving process is complicated and high in computational cost. Image restoration based on most neural networks has high requirements on data sets and the image resolution after restoration is limited because of the lack of quantitative estimation of blurring kernels. In this study, an image restoration method guided by blurring kernel estimation for microscopic defocused images is proposed. First, to reduce the blurring kernel estimation error caused by the positive and negative difference in microscopic defocused imaging, a defocused image classification network is designed to classify the input defocused images with different defocus distances and directions, and its output images are input into the blurring kernel extraction network composed of the feature extraction, correlation, and blurring kernel reconstruction layers. Second, a non-blind defocused image restoration model to restore the high-resolution images is proposed by introducing the blurring kernel extraction module into the restoration network based on U-Net, and the blurring kernel estimation and image restoration losses are jointly trained to realize image restoration guided by blurring kernel estimation. Finally, the experimental results of our proposed method demonstrate significant improvements in both the peak signal-to-noise ratio and structural similarity index measure when compared to other methods.

Developing an effective method of quantifying defects in the bulk of transparent ceramics is a challenging task that could facilitate their widespread use as a substitute for single crystals. Conventionally, SEM analysis is used to examine the microstructure but it is limited to the material surface. On the other hand, optical transmittance assesses material quality, but does not provide information on the size and concentration of defects. In this study, we illustrate the use of a digital optical microscope for the non-destructive, precise, and rapid analysis of residual porosity in transparent ceramics. YAG-based ceramics doped with Yb have been selected for this study because they are used as laser gain media, an application that requires virtually defect-free components. Different production processes were used to produce YAG samples, and the digital optical microscope analysis was used to compare them. This analysis was shown to be effective and precise to measure the size and concentration of the residual pores. In addition, the comparison of samples obtained with different production processes showed that the size and distribution of the residual porosity is affected by the drying step of the powders before shaping by pressing, as well as by the sintering aids used to ease the densification. It also showed that the transmittance is influenced by both the total volume and the concentration of the pores.

Abstract This study aimed to measure marginal and internal fit using images captured with both an optical microscope and a smartphone camera, comparing the fit measurement performance of these devices and analyzing their correlation. Working casts (with 10 posterior and 10 anterior teeth) created to fabricate fixed dental prostheses were used. These working casts were scanned using a desktop scanner (E1) to design an interim crown, and the designed interim crown was fabricated using a three-dimensional (3D) printer. Utilizing the silicone replica technique, the fabricated interim crown replicated the fit, which was then captured using both an optical microscope and a smartphone camera. The captured images were used to measure the marginal and internal fit according to the imaging device. Intraclass correlation coefficients (ICC) were used for reliability analysis according to the imaging device. Furthermore, the Wilcoxon signed-rank test was adopted for the comparative evaluation of the marginal and internal fit between the imaging devices (α = 0.05). The measurement results of the marginal and internal fit according to the optical microscope and smartphone camera did exhibit a significant difference (P

We present a novel optical nanomotion-based rapid antibiotic and antifungal susceptibility test. The technique consisted of studying the effects of antibiotics or antifungals on the nanometric scale displacements of bacteria or yeasts to assess their sensitivity or resistance to drugs. The technique relies on a traditional optical microscope, a video camera, and custom-made image analysis software. It provides reliable results in a time frame of 2–4  h and can be applied to motile, non-motile, fast, and slowly growing microorganisms. Due to its extreme simplicity and low cost, the technique can be easily implemented in laboratories and medical centers in developing countries. [ABSTRACT FROM AUTHOR]

This study aimed to measure marginal and internal fit using images captured with both an optical microscope and a smartphone camera, comparing the fit measurement performance of these devices and analyzing their correlation. Working casts (with 10 posterior and 10 anterior teeth) created to fabricate fixed dental prostheses were used. These working casts were scanned using a desktop scanner (E1) to design an interim crown, and the designed interim crown was fabricated using a three-dimensional (3D) printer. Utilizing the silicone replica technique, the fabricated interim crown replicated the fit, which was then captured using both an optical microscope and a smartphone camera. The captured images were used to measure the marginal and internal fit according to the imaging device. Intraclass correlation coefficients (ICC) were used for reliability analysis according to the imaging device. Furthermore, the Wilcoxon signed-rank test was adopted for the comparative evaluation of the marginal and internal fit between the imaging devices (α = 0.05). The measurement results of the marginal and internal fit according to the optical microscope and smartphone camera did exhibit a significant difference (P < 0.05). The ICC between the two devices showed an “excellent” agreement of over 0.9 at all measurement points (P < 0.001). A smartphone camera could be used to obtain images for evaluating the marginal and internal fit. [ABSTRACT FROM AUTHOR]

Developing an effective method of quantifying defects in the bulk of transparent ceramics is a challenging task that could facilitate their widespread use as a substitute for single crystals. Conventionally, SEM analysis is used to examine the microstructure but it is limited to the material surface. On the other hand, optical transmittance assesses material quality, but does not provide information on the size and concentration of defects. In this study, we illustrate the use of a digital optical microscope for the non-destructive, precise, and rapid analysis of residual porosity in transparent ceramics. YAG-based ceramics doped with Yb have been selected for this study because they are used as laser gain media, an application that requires virtually defect-free components. Different production processes were used to produce YAG samples, and the digital optical microscope analysis was used to compare them. This analysis was shown to be effective and precise to measure the size and concentration of the residual pores. In addition, the comparison of samples obtained with different production processes showed that the size and distribution of the residual porosity is affected by the drying step of the powders before shaping by pressing, as well as by the sintering aids used to ease the densification. It also showed that the transmittance is influenced by both the total volume and the concentration of the pores. [ABSTRACT FROM AUTHOR]

Identifying minerals is essential for geology, mineral exploration, engineering, and environmental sciences. Recent advances in machine learning have illustrated its potential as a fast, cost-effective, and reliable tool for identifying minerals from photographs or photomicrographs. However, in the recent literature, few studies have been dedicated to image acquisition. Machine learning generally requires reproducible, high-quality data to perform complicated tasks such as mineral identification to avoid common pitfalls. In this paper, we propose a practical image acquisition protocol for optical microscopes. This protocol focuses on ensuring reproducibility and enhancing image quality. To favor reproducibility, we detail dealing with camera errors, using reference color gauges, and establishing experimental parameters such as the external light source and temperature. For image enhancement, we explain the importance of lighting and its impact on machine learning precision, selection of the objective, and white balance calibration. In addition, we trialed the protocol on heavy mineral concentrate from till samples (20 species) with a typical deep learning model and it revealed that minor lighting modification (<5% difference in one channel) significantly increased misclassification rates: kyanite from 6.4% to 24.9% and monazite from 6.5% to 42.9%. [ABSTRACT FROM AUTHOR]

The present study describes the results of a pollen analysis carried out using light microscopy of 8 bee pollen samples collected from apiaries established within Moara Domnească experimental station (Ilfov County) during the fall of 2021, after a summer characterized by very hot and dry weather conditions, especially during the months of June and July. The preliminary analysis indicated buckwheat pollen (Fagopyrum esculentum, Fam. Polygonaceae) as predominant in the pollen grains that were analyzed, then it indicated pollen similar to that of sunflower (Helianthus annuus), but also found in other Asteraceae species (Senecio type pollen) and in smaller amounts Crepis type pollen (can be weeds in crops or ruderal plants: Taraxacum, Leontodon, Cichorium, Tragopogon), Fabaceae-like pollen (Trifolium sp.) and Cirsium type pollen (can be Cirsium arvensis - weed in crops, but also other plants). In Romania, there are few areas cultivated with buckwheat, mostly in the northern part of Moldova. However, this is a fast-growing annual that can be grown as a late-season melliferous cover crop, whose flowers provide both pollen and nectar for honey bees and other pollinators. [ABSTRACT FROM AUTHOR]

Despite the effective microbial inactivation of high pressure processing (HPP), too intensive pressurization can cause undesirable quality changes in fish muscle. Combination treatments can be applied to retain sensory attributes after HPP for ready-to-eat fishery products. This present study thus investigated the impacts of different initial sample temperatures (− 18, 2, 20, and 55 °C) on raw grass carp slices under 300, 400, and 500 MPa, followed by microbiological, sensorial, chemical, and structural analyses. Increasing the pressure level at 20 °C led to whitening, hardening, and decreases in water holding capacity of grass carp. For example, 400 MPa induced a L* increase from 59.6 to 80.7, loss in muscle transparency, 5.1% of weight loss, and a hardness increase from 390.2 to 540.5 g. Correspondingly, fiber shrinkage and the compaction of tissue structure were observed in pressurized fish muscle. When grass carp were pressurized at a low initial temperature (2 °C), the appearance remained semi-transparent under 300 MPa, and the changes in physicochemical quality were similar to the treatments at 20 °C. HPP treatments at a subzero (− 18 °C) or mild-heated (55 °C) initial temperature caused greater quality changes when compared to other temperature conditions, e.g., L* > 70 under 300 MPa, and hardness > 700 g under 400 MPa. The myofibrillar protein contents dropped more significantly as the initial temperature increased. Overall, a better understanding of the impacts of pressurization temperatures would thus help to monitor fish quality and develop appropriate means for novel ready-to-eat fish-based products. [ABSTRACT FROM AUTHOR]

Impact of age hardening and incorporation of graphite particles reinforcements on fatigue properties of Aluminum metal matrix composites which were fabricated with liquid metallurgical method is explored in this paper. Fabricated fatigue testing specimens were age hardened at temp of 170 °C and 270 °C to improve fatigue strength. Both aged and ascast specimens were characterized to study fatigue properties at operating temperature.Ggraphite particulate and age hardening temperature influences the fatigue strength of composites owing to its higher fatigue life compaed with as cast condition and age hardening at 270 °C. The incorporation of graphite exhibited remarkable improvement in fatigue strength. The detailed study of fractured surfaces of composites under microscope revealed its failure mechanism. It is found that , hardness increased with aging temperature up to 170 °C, beyond which found to be decreased resulted in formation of precipitation near the grain boundaries and enhanced the hardness of composites. But at 270 °C, both precipitate and grain boundaries abrading reduces both strength and hardness of composite. EDS analysis of composites at different phases for particles and interface between matrix and graphite particles is shown rich phase in aluminium matrix and poor at the interface. [ABSTRACT FROM AUTHOR]

Friction drilling is one of the non-conventional holes making process, it is a clean and chip-less operation which uses the frictional heat to create the hole on base materials. In any kind operations like machining of metal and mining of fuels the microstructure is composed with its various phases of size, variable form, and distribution (dendrites, grains, lamellae, precipitates, spherulites, pores, etc). Friction stir drilling technology is specifically designed for mining operations. The improved microstructure of the drilled holes ensures better load distribution and resistance to wear and tear. This translates into longer tool life, increased operational efficiency, and ultimately higher profitability for mining companies. The microstructure of metals plays a crucial role in the mining industry, primarily in two main aspects-extraction and processing of ores. In this microstructure of friction drilling hole of brittle cast materials like Al6061-T6, has been investigate with the help of optical microscope at various regions like Stirring Zone (SZ), Thermo Mechanical Affected Zone (TMAZ)and Heat Affected Zone (HAZ). Those zones are divided based on tool contact with work piece. It is observed that Al and Si particles are recrystallized structure. Due to thermal energy and forces acting on the material drilled hole contains few adhered at walls. At when compared with the HZA and TMAZ, SZ zone contains smaller mean particles are observed. [ABSTRACT FROM AUTHOR]

In this paper, the microscopy impact on several areas of knowledge is showed through a historical review of microscopy from its origins to the present, follow by a simple description of the optical microscope performance and comparison with the resolving power and cost of the modern electron microscopes. The results of the use of microscopy as a tool to know the microcosm are demonstrated with the important applications that have transcended directly from the scientific to the social field. In conclusion, the window opened by microscopy not only allows us to see beyond the obvious as the fascinating images of the microcosm, but its development has had a transcendental impact on humanity. [ABSTRACT FROM AUTHOR]

The dichroic mirror (DM) is a key component in microscope. We found a ghost in the reflection channel of a dual‐channel fluorescence microscope and studied the relationship between the ghost and the incidence angle θ into the DM. The DM emission surface reflection generated ghost if the θ is not 45°. We analyzed the distance and intensity relationship between the ghost and the primary image, which is θ‐dependent and was demonstrated by imaging live cells and a stage micrometer. The ghost can be eliminated by placing the DM between objective and tube lens, but not between tube lens and detector, ensuring that the incident light into the DM is approximately parallel. Furthermore, the transmitted light of the DM is shifted towards a longer wavelength with increasing θ. Collectively, microscopists must carefully optimize the θ when designing a microscope to avoid the ghost. [ABSTRACT FROM AUTHOR]

We have successfully synthesised silver quantum dots (Ag QDs) via chemical method. We have studied Ag QDs doped 4-(trans-4-n hexylcyclohexyl) isothiocyanatobenzoate (6CHBT) LC hybrid system and their associated structural and optoelectronic properties using both experimental and theoretical methods. The QDs with sizes 4.27 nm−9.56 nm self-assemble to form nano-micro scale hierarchical structures. Theoretical NMR study has been performed using three different methods HF, B3LYP, and wB97XD for pure and Ag NPs doped LC system. NMR data greatly helps us to explore the phenomenological description of the hybrid system by giving us molecular scale insights. Optical microscope, RAMAN, UV, FTIR, HR-XRD, FESEM-EDX, and Fluorescence data confirm the structural and physio-chemical properties of QDs, LC molecules and as well as their hybrid system. We use a nanoscale predictive model to estimate the effective size to which the bandgap value of Ag QDs in a hybrid system corresponds. The bandgap value of pure Ag QDs is found to be 5.32 eV, whereas upon doping these Ag QDs in LC media, their bandgap falls to a value of 4.08 eV. The estimated size (i.e. corresponding to effective confinement) using a hexahedral or octahedral-shaped particle model comes out to be ~15 nm. We successfully synthesized Ag QDs using chemical co-precipitation method. Our FTIR, Raman, UV, FL, XRD data confirm for their crystalline nature and purity. We have doped it in 6CHBT LC media and obtained nano-micro scale clusters. The Ag QDs doped 6CHBT LC hybrid system and their associated chemical and optoelectronic properties have not been studied experimentally and theoretically well. The molecular scale insight for the variations of the optoelectronic properties of the QDs and LC hybrid system is scarcely available in published report. QD sizes 4.2768 nm–9.5662 nm self-assembled to form nano-micro scale hierarchical structures. The smaller size NPs can easily align with the director axis of the LC molecules, whereas the larger ones self assemble and agglomerate with each other to form bigger clusters of Ag NPs. The sizes of the clusters in latter case extend up to a few tens of microns. The hierarchical arrangement of smaller NPs is supposed to be energetically more favourable and form a composite matrix, i.e. LC molecules allow relatively smaller size QDs to form hybrid structure inside LC matrix. We use nanoscale predictive model to estimate the effective size to which the bandgap value of Ag QDs in hybrid system corresponds to. The bandgap value of pure Ag QDs is found to be 5.32 eV, whereas upon doping these Ag QDs in LC media, their bandgap fall to a value of 4.08 eV. The estimated size (i.e. corresponding to effective confinement) using hexahedral- or octahedral-shaped particle model is ~15 nm. We assume that the QDs in LC matrix may arrange themselves in hexahedral or octahedral shape. To some extent, we could narrow down our inferences as direct evidence by imaging at nanoscale does not seem possible due to limitations with imaging soft materials at nanoscales. In order to get molecular scale insight to explore the phenomenon, we have performed NMR characterizations both experimentally and theoretically and compared the two. Theoretical NMR study is performed using three different methods HF, B3LYP, and wB97XD for pure and Ag NPs doped LC system. Variations in chemical shift are presented in greater details. Experimentally and theoretically obtained the NMR results have been successfully correlated with the findings. Presence of sigma hole is observed in the molecular electrostatic potential (MEP) surface of Ag NPs doped LC system. We have highlighted its importance. We have successfully verified the theoretical outcomes with experimental findings. [ABSTRACT FROM AUTHOR]

We present a novel optical nanomotion-based rapid antibiotic and antifungal susceptibility test. The technique consisted of studying the effects of antibiotics or antifungals on the nanometric scale displacements of bacteria or yeasts to assess their sensitivity or resistance to drugs. The technique relies on a traditional optical microscope, a video camera, and custom-made image analysis software. It provides reliable results in a time frame of 2–4 h and can be applied to motile, non-motile, fast, and slowly growing microorganisms. Due to its extreme simplicity and low cost, the technique can be easily implemented in laboratories and medical centers in developing countries.

The resolution of an optical microscope is determined by the overall point spread function of the system. When examining structures significantly smaller than the wavelength of light, the contribution of the background or surrounding environment can profoundly affect the point spread function. This research delves into the impact of reflective planar substrate structures on the system’s resolution. We establish a comprehensive forward imaging model for a reflection-type confocal laser scanning optical microscope, incorporating vector field manipulation to image densely packed nanoparticle clusters. Both theoretical and experimental findings indicate that the substrate causes an interference effect between the background field and the scattered field from the nanoparticles, markedly enhancing the overall spatial resolution. The integration of vector field manipulation with an interferometric scattering approach results in superior spatial resolution for imaging isolated particles and densely distributed nanoscale particle clusters even with deep subwavelength gaps as small as 20 nm between them. However, the method still struggles to resolve nanoparticles positioned directly next to each other without any gap, necessitating further work to enhance the resolving ability. This may involve techniques like deconvolution or machine learning-based post-processing methods.

The present study describes the results of a pollen analysis carried out using light microscopy of a sample of bee pollen collected from a stationary apiary situated in the commune of Cornetu (Ilfov County) in October 2022, during a period with low temperature during the night, and after a summer characterized by very hot weather and severe drought conditions. To determine the preference of pollen sources by the honey bee colony, identification of melliferous plants in the apiary vicinity and up to the periphery of the commune of Cornetu was carried out. Cultured crops such as artichoke, buckwheat, cabbage, common vetch, mustard, phacelia, rape and several autumn-flowering garden plants were blooming at the moment when the current study was carried out. Also, uncultivated areas colonized by allergenic plants were identified in the foraging area around the beehive. After sorting the pollen pellets based on colour, the results indicated several origins of pollen, including pollen of Brassicaceae, Asteraceae, Rosaceae, Portulaca and also pollen of the highly allergenic anemophilous species ragweed - Ambrosia artemisiifolia, known as a popular source of pollen for bees. [ABSTRACT FROM AUTHOR]

Datura sp. and related plants mandrake (Mandragora officinarum and M. autumnalis), black henbane or stinking nightshade (Hyoscyamus niger), belladonna (Atropa belladonna) and angel's trumpets (Brugmansia sp.) are considered some of the deadliest plant species. Datura stramonium (jimson weed, thorn apple or devil's snare) is a weed that sometimes is cultivated as ornamental for its large, white funnel-shaped flowers, but it is considered dangerous due to accidental or deliberate ingestion of any plant parts. Tropane alkaloids (atropine, hyoscyamine, scopolamine) with strong anticholinergic properties can cause a variety of adverse effects that can lead to death in humans and other animals. They are pharmaceutically active and their mind-altering properties have been known since ancient times. Characteristic toxic symptoms can also occur after skin penetration alone and neither drying nor boiling decrease the plant toxicity. Naturally occuring alkaloids (for example from Stramonii folium and Daturae innoxiae herba) or synthetic and semisynthetic substitutes have found use in modern medicine too. The present paper comprises a review on the mechanism of toxicity and photomicrographs of characteristic microscopic features of Datura leaf. [ABSTRACT FROM AUTHOR]

Intensity diffusion caused by optical diffraction limits the imaging resolution of conventional optical microscopes, therefore modelling and measuring the intensity transmission and distribution property of the light sources is a significant research topic in system development and pattern recognition. However, the complicated wave propagation process in optical imaging makes it difficult to provide a direct, analytical and simple mathematical model to measure the relationship between the blur degree and various camera parameters. In this study, an improved intensity transmission and distribution calculation method for conventional optical microscopes was proposed; furthermore, a simple mathematical relation between the blur degree and camera parameters was achieved based on the proposed method. First, the light intensity distribution and propagation characteristics of a conventional optical microscope were modeled based on the property of the Fresnel circular hole diffraction combined with the practical optical parameters. Second, by analyzing the property of intensity distribution and blurring imaging, a quantitative simplified mathematical relationship between the blur degree and camera parameters in optical microscope imaging was obtained, and the three-dimensional (3D) blur property in the optical imaging process was analyzed under different conditions. Third, the connection between diffractive optics and geometric optics was obtained by summarizing and generalizing the 3D blur property curve of each monochromatic light source. Finally, the proposed method was verified through a series of simulations and experiments.

The effect of fusion temperature and duration on the nonisothermal crystallization kinetics of polyamide 6 (PA6) was investigated using differential scanning calorimetry (DSC) and a polarized optical microscope (OM). The rapid cooling method involved heating the polymer above its melting point, holding it at this temperature to ensure complete melting, and then rapidly cooling it to the crystallization temperature. By monitoring the heat flow during cooling, the crystallization kinetics of PA6 were characterized, including the degree of crystallinity, crystallization temperature, and crystallization rate. The study found that changing the fusion temperature and duration significantly impacted the crystallization kinetics of PA6. Increasing the fusion temperature decreased the degree of crystallinity, with smaller nucleation centers requiring a higher degree of supercooling for crystallization. The crystallization temperature shifted towards lower temperatures, and the crystallization kinetics slowed down. The study also found that lengthening the fusion time raised the relative crystallinity, but any further increase did not result in a significant change. The study showed that an increase in fusion temperature led to a longer time needed to reach a given level of crystallinity, reducing the crystallization rate. This can be explained by the thermodynamics of the crystallization process, where higher temperatures promote molecular mobility and crystal growth. Moreover, the study revealed that decreasing a polymer's fusion temperature can lead to a greater degree of nucleation and faster growth of the crystalline phase, which can significantly impact the values of the Avrami parameters used to characterize the crystallization kinetics. [ABSTRACT FROM AUTHOR]

Automating the camera Lucida method which is a standard way for focusing microscopic images is a very challenging study for many scientists. Hence, actually combining hardware and software to automate microscopic imaging systems is one of the most important issues in the field of medicine as well. This idea reduces scanning time and increases the accuracy of user's results in this field. Closed-loop control system has been designed and implemented in the hardware part to move the stage in predefined limits of 15°. This system produces 50 consecutive images from parasites at the mentioned spatial distances in two directions of the z-axis. Then, by introducing our proposed relational software with combining images, a high-contrast image can be presented. This colored image is focused on many subparts of the sample even with different ruggedness. After implementing the closed-loop controller, stages movement was repeated eight times with an average step displacement of 20 μm which were measured in two directions of the z-axis by a digital micrometer. On average, the movement's error was 1 μm. In software, the edge intensity energy index has been calculated for image quality evaluation. The standard camera Lucida method has been simulated with acceptable results based on experts' opinions and also mean squared error parameters. Mechanical movement in stage has an accuracy of about 95% which will meet the expectations of laboratory user. Although output-focused colored images from our combining software can be replaced by the traditional fully accepted Camera Lucida method. [ABSTRACT FROM AUTHOR]

Garment washing of denim fabrics is essential for fading of color, aesthetic effects, vintage look and improvement in handle properties of resulting garments. Denim fabrics of two types, one standard fabric (non-stretch) and other with 2% elastane fiber (stretch), are washed with different industrial washing techniques on Tonello sampling machine. The objective evaluation of handle and mechanical properties of the washed samples are carried out on Kawabata evaluation system (KES-F). Five main characteristics of fabrics are evaluated on KES-F system. The mechanical properties like tensile energy, extensibility and compression energy have increased for both stretch and non-stretch fabrics, while bending stiffness and bending hysteresis have decreased for both types of washed fabrics. The geometrical surface roughness and coefficient of friction have slightly increased after employed washing techniques. The optical microscope is used to investigate the surface changes of the fabric after the employed washing techniques.

The fiber from banana plant (Musa) is an agricultural waste and an abundantly available renewable resource. The purpose of this research paper is to investigate the effect of the mechanical extraction parameters on fiber properties of the ten varieties of banana fiber. This research paper gives physical and chemical properties of 10 selected banana fiber varieties in Sri Lanka. Decortications method are utilized in this study. The instruments used by the researcher were a universal tensile strength machine, Optical microscope, scanning electron microscope (SEM), Data color Spectrophotometer, and FT-IR spectrophotometer. The different banana cultivars vary in properties, the variation being of the order of 63% in terms of diameter (from maximum to minimum),44% in terms of fiber liner density, 31% in terms of strength, 67% in terms of elongation, and 13% in terms of moisture regain. The FTIR absorption bonds revealed that cellulose and non-cellulose components were present in these banana cultivars of fibers. The color of banana fiber varies according to the variety, from off-white natural color to cream, and have little luster effect. The inherent properties of banana fiber obtained from different varieties of stem vary considerably.

The exoscope has been proposed as a valid tool in 5-aminolevulinic acid–guided resection of high-grade gliomas. However, it is not clear if, beyond ergonomics, the exoscope provides a real benefit over the optical microscope (OM). The aim of this study was to compare the exoscope with the OM in terms of surgical visualization and workflow in 5-aminolevulinic acid–guided brain surgery. Surgical videos of patients diagnosed with histopathologically confirmed, Shinoda stage I, high-grade gliomas who underwent surgery in from January to April 2022 were studied. Visualization under a 5-aminolevulinic acid blue filter for vessels, parenchyma, surgical instruments, and fluorescence was categorized for both superficial and deep fields. The following data were also recorded: median number of switches between white light and blue filter, average duration per switch, and amount of work under blue filter. There were 5 surgeries performed under OM guidance and 5 performed under exoscope guidance. Under a blue filter, the exoscope was significantly better than the OM in visualizing vessels, parenchyma, and surgical instruments for both superficial and deep surgical fields. The median number of switches between blue and white light was lower compared with the OM. Both median switch duration and percentage of work under the blue filter were superior when using the exoscope. Within the limitations of a preliminary analysis, use of the exoscope in fluorescence-guided surgery for high-grade gliomas provided significant advantages in terms of visualization of the surgical field under a blue filter and linearity of surgical flow. [ABSTRACT FROM AUTHOR]

This study aims to compare the microstructural and mechanical properties of lightweight polymer concrete (LPC) and lightweight ordinary cement concrete (OCC) before and after exposure to a corrosive acidic environment. In this regard, LPC mixes were prepared with five different unsaturated polyester resin contents (15%–27%) and combinations of lightweight expanded clay aggregate (LECA) and natural river sand. Thereafter, specimens were exposed to sulfuric acid solution for up to 90 days. In addition to visual inspections, physical and mechanical properties [mass and volume changes, compression strength, and modulus of elasticity (MOE)], petrographic inspections, and scanning electron microscope investigations were carried out. Mechanical results showed that LPCs had by far better mechanical features compared with OCC, where at the optimum mix comprised of 24% polymer, reduction of 6% for compression, and 7% for MOE was observed, whereas these values were respectively 70% and 55% for OCC at the same conditions. Outcomes of microscopic observations indicated that increasing the polymer content resulted in strengthening the bond between binder and aggregates where pores were filled by resin. In addition, the impact of the acidic solution on the LPC mixes was less pronounced than for OCC mixes, and lamination of the matrix and affected polymer areas were reduced in LPC mixes with a resin content of 24% and 27%. After 90 days, a slight reduction in properties of LPC specimens and degradation was observed due to the reaction of the acid with the surface of LPC specimens. [ABSTRACT FROM AUTHOR]

Yellow melilot, Melilotus officinalis, belongs to the Fabaceae family. It is abundantly found in Romania. The microscopic analysis of plant material from herbal tea was carried out in the current study. Microscopic evaluation based on the characteristic features of cells, calcium oxalate crystals, trichomes, fibres, vessels, etc. is useful in the initial identification of herbs, as well as for the detection of adulterants, followed by chemical qualitative and quantitative analysis of the raw plant material. [ABSTRACT FROM AUTHOR]

The paper proposes the generalized technique of demodulation, which can be applied for capturing digital three-dimensional images in optical microscopes. This technique allows the calculation of the contrast of harmonic spatial modulation with any values of phase angles. The input data is a stack of digital images with harmonic spatial modulation. Three digital images with different phases of modulation captured in the same focus position are processed to get one data set about the contrast distribution. This data makes it possible to compose the threedimensional images by the selection of the maximal values of the contrast in three-dimensional space. The paper contains the analytical solution of the system with three linear equations that helps to identify the principal parameters of harmonic spatial modulation, including its average value and contrast. As a result, the expression for contrast calculation is present in an analytical form. This expression is valid for any modulation phase angles that do not coincide. The paper contains MathCAD modeling, which illustrates the procedure of composing the threedimensional images. The modeling confirms the correctness of described calculations and demonstrates the built of the three-dimensional surface image as a composition of the contrast distribution map and the corresponded height map. The advantage of the proposed technique is the possibility to apply the economical units for the formation of a harmonious spatial modulation. These units can be installed on most optical microscopes with digital cameras and motorized focusing drives without purchasing expensive commercial software. It significantly reduces the price of transforming these optical microscopes into instruments for capturing digital three-dimensional images. [ABSTRACT FROM AUTHOR]

In this study, suitable solvent and temperature conditions to observe ice crystals in ice cream were examined using an optical microscope. Several types of organic solvents were compared at three temperatures. Ice crystals in ice cream can be observed using kerosene at temperatures below -20 °C. Kerosene possesses low water solubility, and its density and refractive index are significantly different from those of ice. Consequently, the ice crystal borders can be observed clearly. Additionally, the low viscosity of kerosene resulted in few air bubbles. Therefore, this study confirms the feasibility of using kerosene to observe ice crystals in ice cream at temperatures below -20 °C. [ABSTRACT FROM AUTHOR]

Identifying minerals is essential for geology, mineral exploration, engineering, and environmental sciences. Recent advances in machine learning have illustrated its potential as a fast, cost-effective, and reliable tool for identifying minerals from photographs or photomicrographs. However, in the recent literature, few studies have been dedicated to image acquisition. Machine learning generally requires reproducible, high-quality data to perform complicated tasks such as mineral identification to avoid common pitfalls. In this paper, we propose a practical image acquisition protocol for optical microscopes. This protocol focuses on ensuring reproducibility and enhancing image quality. To favor reproducibility, we detail dealing with camera errors, using reference color gauges, and establishing experimental parameters such as the external light source and temperature. For image enhancement, we explain the importance of lighting and its impact on machine learning precision, selection of the objective, and white balance calibration. In addition, we trialed the protocol on heavy mineral concentrate from till samples (20 species) with a typical deep learning model and it revealed that minor lighting modification (

Tinplating on steel is a useful industrial process extensively used for food packaging. Cold-rolled annealed steel coated with tin gives the steel corrosion resistance property and a beautiful luster. Tinplating on steel is a complex process where rolled and annealed steel sheets are cleaned with acid to remove rust, grease, or oil from the surface. Pure tin is electrodeposited on this freshly prepared surface after the electrodeposition of tin on the steel strip; the surface becomes lustrous, the color of pure tin appears, and the finish is called matte. Very often, the flowing heat treatment is just about the tin melting point of 232°C–265°C. After electrodeposition, pure tin deposits on the steel surface; however, a chemical reaction between tin and iron occurs during the brightening treatment. This process results in iron–tin intermetallic formation; their orientation grain structure and orientation of substrate steel all have a synergistic effect on the final properties of tin-coated steel. In the present study, an attempt has been made to study this parameter in detail. A total of five commercially produced tin-plated steel have been selected for the present purpose, and both tin coating and substrate steel have been thoroughly characterized by optical microscopy, scanning electron microscopy, X-ray diffraction (XRD), and the crystallographic texture point of view; however, the best result has been discussed in this paper. The different phases of tin and the iron–tin compound have been identified using XRD, X-ray, and a texture goniometer that are used to find out the crystallographic texture observed in the presence of FeSn2, FeSn, and Sn in tin coating; the volume fraction of these phases is observed to vary from one sample to another. This variation may affect tinplating steel’s final property, which can be studied in the future work.

Garment washing of denim fabrics is essential for fading of color, aesthetic effects, vintage look and improvement in handle properties of resulting garments. Denim fabrics of two types, one standard fabric (non-stretch) and other with 2% elastane fiber (stretch), are washed with different industrial washing techniques on Tonello sampling machine. The objective evaluation of handle and mechanical properties of the washed samples are carried out on Kawabata evaluation system (KES-F). Five main characteristics of fabrics are evaluated on KES-F system. The mechanical properties like tensile energy, extensibility and compression energy have increased for both stretch and non-stretch fabrics, while bending stiffness and bending hysteresis have decreased for both types of washed fabrics. The geometrical surface roughness and coefficient of friction have slightly increased after employed washing techniques. The optical microscope is used to investigate the surface changes of the fabric after the employed washing techniques. [ABSTRACT FROM AUTHOR]

The fiber from banana plant (Musa) is an agricultural waste and an abundantly available renewable resource. The purpose of this research paper is to investigate the effect of the mechanical extraction parameters on fiber properties of the ten varieties of banana fiber. This research paper gives physical and chemical properties of 10 selected banana fiber varieties in Sri Lanka. Decortications method are utilized in this study. The instruments used by the researcher were a universal tensile strength machine, Optical microscope, scanning electron microscope (SEM), Data color Spectrophotometer, and FT-IR spectrophotometer. The different banana cultivars vary in properties, the variation being of the order of 63% in terms of diameter (from maximum to minimum),44% in terms of fiber liner density, 31% in terms of strength, 67% in terms of elongation, and 13% in terms of moisture regain. The FTIR absorption bonds revealed that cellulose and non-cellulose components were present in these banana cultivars of fibers. The color of banana fiber varies according to the variety, from off-white natural color to cream, and have little luster effect. The inherent properties of banana fiber obtained from different varieties of stem vary considerably. [ABSTRACT FROM AUTHOR]

The pour-plate method, a conventional approach to the evaluation of food microbial contamination, is costly and time-consuming. We have developed a novel and efficient system to evaluate microbial growth on the surfaces of foods using a membrane filter and microscope followed by image analysis. While Wickerhamomyces anomalus cells directly inoculated onto loin ham were undetectable because of the complex surface structure of the food, the placement of a hydrophilic polytetrafluoroethylene membrane filter on the loin ham enabled us to clearly observe the yeast cells on the filter by microscopy without affecting their growth. Under microscopic observation, cells on the membrane filter as well as those on the agar plate were always observed with surrounding annular dark regions, which were separated from the background by clear boundaries. We defined the areas inside the boundaries, including the cells and the annular dark regions, as the "bounded areas". In image analysis, the numbers of pixels in the bounded areas increased exponentially in parallel with the viable cell count (CFU/g), suggesting that the pixel numbers were proportional to the viable cell numbers. We applied this system to investigate the adverse effects of sorbic acid preparation (SAP), a common food preservative, on yeast growth. The yeast was incubated on filter-overlaid agar medium in the presence or absence of SAP, resulting in a dose-dependent reduction in the specific pixel increase rate (k [/h]) determined by image analysis as well as in the specific growth rate (μ [/h]) estimated by the agar-plate-based conventional method. Regression analysis revealed a strong correlation between the k and μ values (R2, 0.985) normalized to the corresponding values without SAP. Our system could be applied to estimate the growth rate of microbes on foods and to examine the effects of environmental factors on microbial growth by using the k value as an index. Furthermore, this system would contribute to enhancing food safety, extending shelf life, and solving the important global problem of food loss. • An efficient system for evaluating microbial growth on food surfaces was developed. • Key features are use of a membrane filter on the food and microscopic image analysis. • Characteristic bounded areas around the cells enabled quantitative image analysis. • The system can be used to evaluate cell growth rate and food preservative effects. • The system contributes to research on food preservation and reduce food loss. [ABSTRACT FROM AUTHOR]

Combining materials science, artificial intelligence (AI) offers great potential for the extensive quantitative analysis and processing of material characterization associated with high-throughput experiments. However, due to the complex and diverse morphology of structural components, the development of AI models requires substantial annotation and models are usually task-specific with limited generalizability to different clinical applications. Here, we present a universal self-supervised learning framework for microscopic images. Our framework learns generalizable representations from unlabelled images and provides a pixel-wise segmentation for quantitative microstructure analysis in a variety of materials science applications. Specifically, the framework learns feature from a single image by means of self-supervised learning, and adapts it to a series of related tasks. We show that our method consistently outperforms several comparisons supervised or weakly supervised learning models in the context of various applications. Our approach provides a generalizable solution to improve model performance and alleviate the annotation workload of experts to enable practical AI applications from microscopic imaging. [Display omitted] • We propose a general-purpose self-supervised learning framework for efficient and accurate analysis of microscopy images. • This framework employs clustering and the gradient convergence model (GCM) approach to generate pseudo-labels that can adapt to various representation methods and materials. • We introduce a specialized loss function to handle errors in the pseudo-labels. • We conducted extensive quantitative experiments to validate the superiority of our method. [ABSTRACT FROM AUTHOR]