Displaying publications 1 - 20 of 1671 in total

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  1. Brooke GE
    Matched MeSH terms: Microscopy
  2. Erten M, Tuncer I, Barua PD, Yildirim K, Dogan S, Tuncer T, et al.
    J Digit Imaging, 2023 Aug;36(4):1675-1686.
    PMID: 37131063 DOI: 10.1007/s10278-023-00827-8
    Microscopic examination of urinary sediments is a common laboratory procedure. Automated image-based classification of urinary sediments can reduce analysis time and costs. Inspired by cryptographic mixing protocols and computer vision, we developed an image classification model that combines a novel Arnold Cat Map (ACM)- and fixed-size patch-based mixer algorithm with transfer learning for deep feature extraction. Our study dataset comprised 6,687 urinary sediment images belonging to seven classes: Cast, Crystal, Epithelia, Epithelial nuclei, Erythrocyte, Leukocyte, and Mycete. The developed model consists of four layers: (1) an ACM-based mixer to generate mixed images from resized 224 × 224 input images using fixed-size 16 × 16 patches; (2) DenseNet201 pre-trained on ImageNet1K to extract 1,920 features from each raw input image, and its six corresponding mixed images were concatenated to form a final feature vector of length 13,440; (3) iterative neighborhood component analysis to select the most discriminative feature vector of optimal length 342, determined using a k-nearest neighbor (kNN)-based loss function calculator; and (4) shallow kNN-based classification with ten-fold cross-validation. Our model achieved 98.52% overall accuracy for seven-class classification, outperforming published models for urinary cell and sediment analysis. We demonstrated the feasibility and accuracy of deep feature engineering using an ACM-based mixer algorithm for image preprocessing combined with pre-trained DenseNet201 for feature extraction. The classification model was both demonstrably accurate and computationally lightweight, making it ready for implementation in real-world image-based urine sediment analysis applications.
    Matched MeSH terms: Microscopy
  3. Then SM, Kokolski M, Mbaki Y, Merrick D, Anderson S
    Anat Histol Embryol, 2023 Jan;52(1):21-30.
    PMID: 36373558 DOI: 10.1111/ahe.12888
    Histology is often taught in higher education settings using online virtual microscopes (VM). This study aimed to develop and evaluate the use of VM in teaching on a BSc degree at the University of Nottingham by surveying students and staff. A key development was the use of an e-workbook so that students were actively engaged in creating their own bespoke revision material. Subsequently, this approach was used in a second study evaluating the use of VM in teaching the histology and pathology of the gastrointestinal (GI) tract via group work with students from two BSc courses at the University of Nottingham; one based at Derby (RDHC) and the other in Malaysia (UNMC). Students worked together in groups to complete an e-workbook, develop a presentation, and decide how to collaborate and communicate. An evaluation of these activities revealed advantages in developing transferrable skills, and good engagement with both the histology topic and group work. Analysis of assessment of the module at UNMC showed that student performance improved in the histology-based module after the intervention (p 
    Matched MeSH terms: Microscopy/methods; Microscopy/veterinary
  4. Tan YF, Leong CF, Cheong SK
    Malays J Pathol, 2010 Dec;32(2):97-102.
    PMID: 21329180 MyJurnal
    Dendritic cells (DCs) are professional antigen presenting cells of the immune system. They can be generated in vitro from peripheral blood monocytes supplemented with GM-CSF, IL-4 and TNF alpha. During induction, DCs will increase in size and acquire multiple cytoplasmic projections when compared to their precursor cells such as monocytes or haematopoietic stem cells which are usually round or spherical. Morphology of DCs can be visualized by conventional light microscopy after staining or phase-contrast inverted microscopy or confocal laser scanning microscopy. In this report, we described the morphological appearances of DCs captured using the above-mentioned techniques. We found that confocal laser scanning microscopy yielded DCs images with greater details but the operating cost for such a technique is high. On the other hand, the images obtained through light microscopy after appropriate staining or phase contrast microscopy were acceptable for identification purpose. Besides, these equipments are readily available in most laboratories and the cost of operation is affordable. Nevertheless, morphological identification is just one of the methods to characterise DCs. Other methods such as phenotypic expression markers and mixed leukocyte reactions are additional tools used in the characterisation of DCs.
    Matched MeSH terms: Microscopy, Phase-Contrast*; Microscopy, Confocal*
  5. Sim KS, Cheng Z, Chuah HT
    Scanning, 2004 12 23;26(6):287-95.
    PMID: 15612206
    A new technique based on the statistical autoregressive (AR) model has recently been developed as a solution to signal-to-noise (SNR) estimation in scanning electron microscope (SEM) images. In the present study, we propose to cascade the Lagrange time delay (LTD) estimator with the AR model. We call this technique the mixed Lagrange time delay estimation autoregressive (MLTDEAR) model. In a few test cases involving different images, this model is found to present an optimum solution for SNR estimation problems under different noise environments. In addition, it requires only a small filter order and has no noticeable estimation bias. The performance of the proposed estimator is compared with three existing methods: simple method, first-order linear interpolator, and AR-based estimator over several images. The efficiency of the MLTDEAR estimator, being more robust with noise, is significantly greater than that of the other three methods.
    Matched MeSH terms: Microscopy, Electron, Scanning
  6. Alqahtani A, Sani SFA, Narissa NHA, Alanazi A, Podolyak Z, Nisbet A, et al.
    Appl Radiat Isot, 2020 Jun;160:109132.
    PMID: 32351224 DOI: 10.1016/j.apradiso.2020.109132
    As a result of the various evolving needs, thermoluminescence dosimetry is constantly under development, with applications intended in environmental and personal radiation monitoring through to the sensing of radiotherapy and radiation processing doses. In radiotherapy dosimetry challenges include small-field profile evaluation, encompassing the fine beams of radiosurgery, evaluations confronting the steep dose gradients of electronic brachytherapy and the high dose rates of FLASH radiotherapy. Current work concerns the thermoluminescent dosimetric properties of commercial low-cost borosilicate glass in the form of thin (sub-mm to a few mm) plates, use being made of microscope cover-slips irradiated using clinical external-beam radiotherapy facilities as well as through use of 60Co gamma irradiators. In using megavoltage photons and MeV electrons, characterization of the dosimetric response has been made for cover-slips of thicknesses up to 4 mm. Reproducibility to within +/5% has been obtained. In particular, for doses up to 10 Gy, the borosilicate cover-slips have been demonstrated to have considerable potential for use in high spatial resolution radiotherapy dosimetry, down to 0.13 mm in present work, with a coefficient of determination in respect of linearity of >0.99 for the thinner cover-slips. Results are also presented for 0.13- and 1.00-mm thick cover slips irradiated to 60Co gamma-ray doses, initially in the range 5- to 25 Gy, subsequently extended to 5 kGy-25 kGy, again providing linear response.
    Matched MeSH terms: Microscopy/instrumentation*
  7. Wan Mohamad WAF, Buckow R, Augustin M, McNaughton D
    Food Chem, 2017 Oct 15;233:197-203.
    PMID: 28530566 DOI: 10.1016/j.foodchem.2017.04.086
    Confocal Raman microscopy (CRM) was able to quantify the β-carotene concentration in oil droplets and determine the partitioning characteristics of β-carotene within the emulsion system in situ. The results were validated by a conventional method involving solvent extraction of β-carotene separately from the total emulsion as well as the aqueous phase separated by centrifugation, and quantification by absorption spectrophotometry. CRM also enabled the localization of β-carotene in an emulsion. From the Raman image, the β-carotene partitioning between the aqueous and oil phases of palm olein-in-water emulsions stabilized by whey protein isolate (WPI) was observed. Increasing the concentration of β-carotene in an emulsion (from 0.1 to 0.3g/kg emulsion) with a fixed gross composition (10% palm olein:2% WPI) decreased the concentration of β-carotene in the oil droplet. CRM is a powerful tool for in situ analyses of components in heterogeneous systems such as emulsions.
    Matched MeSH terms: Microscopy, Confocal*
  8. Guo L, Zhu J, Wang K, Cheng KK, Xu J, Dong L, et al.
    Anal Chem, 2023 Jun 27;95(25):9714-9721.
    PMID: 37296503 DOI: 10.1021/acs.analchem.3c02002
    High-resolution reconstruction has attracted increasing research interest in mass spectrometry imaging (MSI), but it remains a challenging ill-posed problem. In the present study, we proposed a deep learning model to fuse multimodal images to enhance the spatial resolution of MSI data, namely, DeepFERE. Hematoxylin and eosin (H&E) stain microscopy imaging was used to pose constraints in the process of high-resolution reconstruction to alleviate the ill-posedness. A novel model architecture was designed to achieve multi-task optimization by incorporating multi-modal image registration and fusion in a mutually reinforced framework. Experimental results demonstrated that the proposed DeepFERE model is able to produce high-resolution reconstruction images with rich chemical information and a detailed structure on both visual inspection and quantitative evaluation. In addition, our method was found to be able to improve the delimitation of the boundary between cancerous and para-cancerous regions in the MSI image. Furthermore, the reconstruction of low-resolution spatial transcriptomics data demonstrated that the developed DeepFERE model may find wider applications in biomedical fields.
    Matched MeSH terms: Microscopy*
  9. Al-Saffar Y, Moo EK, Pingguan-Murphy B, Matyas J, Korhonen RK, Herzog W
    Connect Tissue Res, 2023 May;64(3):294-306.
    PMID: 36853960 DOI: 10.1080/03008207.2023.2166500
    Cartilage cracks disrupt tissue mechanics, alter cell mechanobiology, and often trigger tissue degeneration. Yet, some tissue cracks heal spontaneously. A primary factor determining the fate of tissue cracks is the compression-induced mechanics, specifically whether a crack opens or closes when loaded. Crack deformation is thought to be affected by tissue structure, which can be probed by quantitative polarized light microscopy (PLM). It is unclear how the PLM measures are related to deformed crack morphology. Here, we investigated the relationship between PLM-derived cartilage structure and mechanical behavior of tissue cracks by testing if PLM-derived structural measures correlated with crack morphology in mechanically indented cartilages.

    METHODS: Knee joint cartilages harvested from mature and immature animals were used for their distinct collagenous fibrous structure and composition. The cartilages were cut through thickness, indented over the cracked region, and processed histologically. Sample-specific birefringence was quantified as two-dimensional (2D) maps of azimuth and retardance, two measures related to local orientation and degree of alignment of the collagen fibers, respectively. The shape of mechanically indented tissue cracks, measured as depth-dependent crack opening, were compared with azimuth, retardance, or "PLM index," a new parameter derived by combining azimuth and retardance.

    RESULTS: Of the three parameters, only the PLM index consistently correlated with the crack shape in immature and mature tissues.

    CONCLUSION: In conclusion, we identified the relative roles of azimuth and retardance on the deformation of tissue cracks, with azimuth playing the dominant role. The applicability of the PLM index should be tested in future studies using naturally-occurring tissue cracks.

    Matched MeSH terms: Microscopy, Polarization/methods
  10. Haafiz MK, Hassan A, Khalil HP, Fazita MR, Islam MS, Inuwa IM, et al.
    Int J Biol Macromol, 2016 Apr;85:370-8.
    PMID: 26772914 DOI: 10.1016/j.ijbiomac.2016.01.004
    In this work, polylactic acid (PLA) reinforced cellulose nanowhiskers (CNW) were prepared through solution casting technique. The CNW was first isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC) by using 64% H2SO4 and was designated as CNW-S. The optical microscopy revealed that the large particle of OPEFB-MCC has been broken down by the hydrolysis treatment. The atomic force microscopy confirmed that the CNW-S obtained is in nanoscale dimension and appeared in individual rod-like character. The produced CNW-S was then incorporated with PLA at 1, 3, and 5 parts per hundred (phr) resins for the PLA-CNW-S nanocomposite production. The synthesized nanocomposites were then characterized by a mean of tensile properties and thermal stability. Interestingly to note that incorporating of 3 phr/CNW-S in PLA improved the tensile strength by 61%. Also, CNW-S loading showed a positive impact on the Young's modulus of PLA. The elongation at break (Eb) of nanocomposites, however, decreased with the addition of CNW-S. Field emission scanning electron microscopy and transmission electron microscopy revealed that the CNW-S dispersed well in PLA at lower filler loading before it started to agglomerate at higher CNW-S loading (5phr). The DSC analysis of the nanocomposites obtained showed that Tg,Tcc and Tm values of PLA were improved with CNW-S loading. The TGA analysis however, revealed that incopreated CNW-S in PLA effect the thermal stability (T10,T50 and Tmax) of nanocomposite, where it decrease linearly with CNW-S loading.
    Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Atomic Force; Microscopy, Electron, Transmission
  11. Mamat H, Hill SE
    J Food Sci Technol, 2014 Sep;51(9):1998-2005.
    PMID: 25190856 DOI: 10.1007/s13197-012-0708-x
    Fat is an important ingredient in baking products and it plays many roles in providing desirable textural properties of baking products, particularly biscuit. In this study, the effect of fat types on dough rheological properties and quality of semi-sweet biscuit (rich tea type) were investigated using various techniques. Texture profile and extensibility analysis were used to study the dough rheology, while three-point bend test and scanning electron microscopy were used to analyse the textural characteristics of final product. TPA results showed that the type of fat significantly influenced dough textural properties. Biscuit produced with higher solid fat oil showed higher breaking force but this was not significantly different when evaluated by sensory panel. Scanning electron microscopy showed that biscuit produced with palm mid-fraction had an open internal microstructure and heterogeneous air cells as compared to other samples.
    Matched MeSH terms: Microscopy, Electron, Scanning
  12. Ahmad M, Zafar M, Sultana S, Ahmad M, Abbas Q, Ayoub M, et al.
    Microsc Res Tech, 2018 Sep;81(9):1004-1016.
    PMID: 30303585 DOI: 10.1002/jemt.23066
    Pollen micro-morphological features have proven to be helpful for the plant taxonomists in the identification and classification of plants. The utilization of this plantmayhelpfulin the areas of lignocellulosic conversion to biofuels and diversify application toward biomass. The current study was planned with the aim to evaluate the pollen features of complex Ranunculaceous flora of District Chitral, Northern Pakistan using both scanning electron microscopy (SEM) and Light Microscope (LM) for their taxonomic importance. Pollens of 18 Ranunculaceous species belonging to 6 genera were collected from different localities of the research area. SEM and LM were used to examine both qualitative and quantitative micro-morphological features. Sculptring of the sexine include; Scabrate, psilate, echinate, verrucate, perforate gemmate, and reticulate and so forth. Shape of the pollens was sub-spheroidal, spheroidal, prolate, subprolate and oblate and so forth. Type of pollen was ranged from mono to tricolpate and tricolporate. Quantitative characters include length/width of the pollen, colpus, exine thickness, and P/E ratio. Based on these micro-morphological features a taxonomic key was prepared for the fast and correct identification. RESEARCH HIGHLIGHT: Study of the pollen micro-morphological features of Ranunculaceous species by SEM and LM. Analysing both qualitative and quantitative characters of the pollens. Preparation of taxonomic key based on micro-morphological features for the correct and fast identification.
    Matched MeSH terms: Microscopy/methods*; Microscopy, Electron, Scanning/methods*
  13. Lee GE
    Data Brief, 2020 Feb;28:104958.
    PMID: 31890799 DOI: 10.1016/j.dib.2019.104958
    The morphological data of Malesian Lejeunea is described in detail based on examination of about 600 fresh specimens and 1500 herbarium specimens of Lejeunea from other herbaria. Scanning electron microscopy (SEM) images and photographs illustrating the characters of Lejeunea are presented.
    Matched MeSH terms: Microscopy, Electron, Scanning
  14. Sim KS, Huang YH
    Scanning, 2015 Nov-Dec;37(6):381-8.
    PMID: 25969945 DOI: 10.1002/sca.21226
    This is the extended project by introducing the modified dynamic range histogram modification (MDRHM) and is presented in this paper. This technique is used to enhance the scanning electron microscope (SEM) imaging system. By comparing with the conventional histogram modification compensators, this technique utilizes histogram profiling by extending the dynamic range of each tile of an image to the limit of 0-255 range while retains its histogram shape. The proposed technique yields better image compensation compared to conventional methods.
    Matched MeSH terms: Microscopy, Electron, Scanning
  15. Nagaki K, Furuta T, Yamaji N, Kuniyoshi D, Ishihara M, Kishima Y, et al.
    Chromosome Res, 2021 12;29(3-4):361-371.
    PMID: 34648121 DOI: 10.1007/s10577-021-09676-z
    Observing chromosomes is a time-consuming and labor-intensive process, and chromosomes have been analyzed manually for many years. In the last decade, automated acquisition systems for microscopic images have advanced dramatically due to advances in their controlling computer systems, and nowadays, it is possible to automatically acquire sets of tiling-images consisting of large number, more than 1000, of images from large areas of specimens. However, there has been no simple and inexpensive system to efficiently select images containing mitotic cells among these images. In this paper, a classification system of chromosomal images by deep learning artificial intelligence (AI) that can be easily handled by non-data scientists was applied. With this system, models suitable for our own samples could be easily built on a Macintosh computer with Create ML. As examples, models constructed by learning using chromosome images derived from various plant species were able to classify images containing mitotic cells among samples from plant species not used for learning in addition to samples from the species used. The system also worked for cells in tissue sections and tetrads. Since this system is inexpensive and can be easily trained via deep learning using scientists' own samples, it can be used not only for chromosomal image analysis but also for analysis of other biology-related images.
    Matched MeSH terms: Microscopy
  16. Hanifah AH, Teng ST, Law IK, Abdullah N, Chiba SUA, Lum WM, et al.
    Harmful Algae, 2022 Dec;120:102338.
    PMID: 36470602 DOI: 10.1016/j.hal.2022.102338
    Thirty-four strains of Heterocapsa were established from Malaysian waters and their morphologies were examined by light, scanning, and transmission electron microscopy. Three species, H. bohaiensis, H. huensis, and H. rotundata, and three new species, H. borneoensis sp. nov., H. limii sp. nov., and H. iwatakii sp. nov. were described in this study. The three species were differentiated morphologically by unique characteristics of cell size, shape, displacement of the cingulum, shape and position of nucleus, the number and position of pyrenoids, and body scale ultrastructure. The species delimitations were robustly supported by the molecular data. A light-microscopy-based key to species of Heterocapsa is established, with two major groups, i.e., species with a single pyrenoid, and species with multiple pyrenoids. Bioassays were conducted by exposing Artemia nauplii to Heterocapsa densities of 1-5 × 105 cells mL-1, and treatments exposed to H. borneoensis showed naupliar mortality, while no naupliar death was observed in the treatments exposed to cells of H. bohaiensis, H. huensis, H. limii, and H. iwatakii. Naupliar death was observed during the initial 24 h for both tested H. borneoensis strains, and mortality rates increased up to 50% after 72-h exposure. This study documented for the first time the diversity and cytotoxic potency of Heterocapsa species from Malaysian waters.
    Matched MeSH terms: Microscopy, Electron, Transmission
  17. Taha BA, Mashhadany YA, Al-Jumaily AHJ, Zan MSDB, Arsad N
    Viruses, 2022 Oct 28;14(11).
    PMID: 36366485 DOI: 10.3390/v14112386
    The SARS-CoV-2 virus is responsible for the rapid global spread of the COVID-19 disease. As a result, it is critical to understand and collect primary data on the virus, infection epidemiology, and treatment. Despite the speed with which the virus was detected, studies of its cell biology and architecture at the ultrastructural level are still in their infancy. Therefore, we investigated and analyzed the viral morphometry of SARS-CoV-2 to extract important key points of the virus's characteristics. Then, we proposed a prediction model to identify the real virus levels based on the optimization of a full recurrent neural network (RNN) using transmission electron microscopy (TEM) images. Consequently, identification of virus levels depends on the size of the morphometry of the area (width, height, circularity, roundness, aspect ratio, and solidity). The results of our model were an error score of training network performance 3.216 × 10-11 at 639 epoch, regression of -1.6 × 10-9, momentum gain (Mu) 1 × 10-9, and gradient value of 9.6852 × 10-8, which represent a network with a high ability to predict virus levels. The fully automated system enables virologists to take a high-accuracy approach to virus diagnosis, prevention of mutations, and life cycle and improvement of diagnostic reagents and drugs, adding a point of view to the advancement of medical virology.
    Matched MeSH terms: Microscopy, Electron, Transmission
  18. Chamathka WWDR, Chai TT, Phuah ET, Wong JX, Chen SN, Yassoralipour A
    Int J Biol Macromol, 2024 Mar;260(Pt 2):129637.
    PMID: 38262554 DOI: 10.1016/j.ijbiomac.2024.129637
    The research aimed to explore the potential of palm kernel meal (PKM) as a sustainable source of cellulose nanoparticles (CNPs) for active food packaging. The CNPs were isolated using a combination of chemical techniques, such as alkaline treatment, bleaching, and acid hydrolysis. The characterization of the CNPs was analysed using various techniques, including scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and UV-visible spectroscopy. The findings revealed that chemical processing effectively removed lignin and hemicellulose from PKM. The SEM morphology confirmed the separation of the CNPs, resulting in the production of 40-100 nm spherical cellulose nanoparticles, while XRD and FTIR analyses confirmed their purity and composition. Moreover, the UV-visible spectroscopy exhibited high transmittance rates, indicating the potential of CNPs as reinforcing agents for polymer matrices. The significance of utilising PKM as a valuable fibre source for extracting CNPs can be recommended for developing active food packaging.
    Matched MeSH terms: Microscopy, Electron, Scanning
  19. Donworth P, Wesener T
    Zootaxa, 2024 Mar 08;5419(4):545-562.
    PMID: 38480309 DOI: 10.11646/zootaxa.5419.4.4
    Thailand hosts a very rich but underexplored giant pill-millipede (Sphaerotheriida) fauna, with 11 of its 13 species described in the last three years. Currently, all known Thai giant pill-millipedes belong to the genera Zephronia Gray, 1832 (nine species) and Sphaerobelum Verhoeff, 1924 (four species). Here we describe the first two species of the genus Prionobelum Verhoeff, 1924 (previously restricted to Vietnam and China), Prionobelum inthanonense n. sp. and P. naevium n. sp. from Thailand. The species occur at Thailands highest mountain (2500 m) Doi Inthanon and the lowland rainforests at Bang Lang National Park touching the border with Malaysia. Both species are described integratively, utilizing light microscopy, scanning electron microscopy as well as DNA barcoding. Both new species of Prionobelum differ from other Zephroniidae species, as well as from one another, by more than 20% p-distance in the COI barcoding gene suggesting that potential closer related species are still awaiting discovery.
    Matched MeSH terms: Microscopy, Electron, Scanning
  20. Hussein HT, Kadhim A, Al-Amiery AA, Kadhum AA, Mohamad AB
    ScientificWorldJournal, 2014;2014:842062.
    PMID: 25136694 DOI: 10.1155/2014/842062
    Influence of laser treatment on mechanical properties, wear resistance, and Vickers hardness of aluminum alloy was studied. The specimens were treated by using Nd:YaG laser of energy 780 mj, wavelength 512 nm, and duration time 8 ns. The wear behavior of the specimens was studied for all specimens before and after treatment by Nd:YaG laser and the dry wear experiments were carried out by sing pinon-disc technique. The specimens were machined as a disk with diameter of 25 mm and circular groove in depth of 3 mm. All specimens were conducted by scanning electron microscopy (SEM), energy-dispersive X-ray fluorescence analysis (EDS), optical microscopy, and Vickers hardness. The results showed that the dry wear rate was decreased after laser hardening and increased Vickers hardness values by ratio of 2.4:1. The results showed that the values of wear rate for samples having circular grooves are less than samples without grooves after laser treatment.
    Matched MeSH terms: Microscopy; Microscopy, Electron, Scanning
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