Micron最新文献

{"title":"Insight into structural and chemical profile / composition of powdered enamel and dentine in different types of permanent human teeth","authors":"Katarzyna Sarna-Boś ,&nbsp;Patrycja Boguta ,&nbsp;Monika Szymańska-Chargot ,&nbsp;Kamil Skic ,&nbsp;Artur Zdunek ,&nbsp;Piotr Stachurski ,&nbsp;Marin Vodanovic ,&nbsp;Renata Chałas","doi":"10.1016/j.micron.2024.103608","DOIUrl":"https://doi.org/10.1016/j.micron.2024.103608","url":null,"abstract":"<div><p>Research on the structure and chemical composition of dental tissues allows for the optimisation of materials used in the treatment and care of teeth. Understanding pathological processes occurring in dental tissues and their reactions to various substances, including dental materials, are crucial for the development of new dental technologies.</p><p>The aim of the study was to check the similarities in the chemical and morphological structure of enamel and dentine powders in various groups of permanent teeth, as well as differential chemical analysis for both grinded tissues tested.</p><p>The extracted non-carious and non-pathological human permanent teeth were divided into four groups: incisors, canines, premolars and molars. Each tooth was sectioned to thick slices. Enamel and dentine were mechanically separated and ground in an agate mortar and pestle. FT-Raman and FTIR spectroscopy methods were used for the analysis of biological tissues. SEM method was applied to visualise hard dental tissues structures present on the surface and within the particles.</p><p>The morphological structures were the same within the analysed tissues and did not depend on the analysed group of teeth. A comparison of the mineral-to-organic ratios of enamel and dentine in each tooth group showed that the bands related to PO₄^3- were clearly higher in content for enamel than for dentine. Higher absorbance measured at the region of 2800–3700 cm⁻¹ and at 1500–1800 cm⁻¹ for dentine as compared to enamel samples were indicative of a higher content of organic structures. The highest contribution of phosphates was in canine enamel samples.The studies showed that the carbonate-to-phosphate ratio was higher for dentine (0.20 - 0.48) compared to the values obtained for enamel (0.13 - 0.22), however, minor differences were found in each group of enamel or dentine samples.</p><p>The lack of significant differences between the enamel and dentine powders of incisors, canines, premolars and molars may prove that each extracted tooth, regardless of the tooth group, is an excellent substrate for their substitution.</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139732831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review of recent advancement in covalent organic framework (COFs) synthesis and characterization with a focus on their applications in antibacterial activity","authors":"F. Al-dolaimy ,&nbsp;Shelesh Krishna Saraswat ,&nbsp;Baydaa Abed Hussein ,&nbsp;Uday Abdul-Reda Hussein ,&nbsp;Shakir Mahmood Saeed ,&nbsp;Ashwaq Talib Kareem ,&nbsp;Alzahraa S. Abdulwahid ,&nbsp;Thair L. Mizal ,&nbsp;Khursheed Muzammil ,&nbsp;Ahmed Hussien Alawadi ,&nbsp;Ali Alsalamy ,&nbsp;Farah Hussin ,&nbsp;Mazin Hadi Kzarb","doi":"10.1016/j.micron.2024.103595","DOIUrl":"10.1016/j.micron.2024.103595","url":null,"abstract":"<div><p>The primary objective of this review is to present a comprehensive examination of the synthesis, characterization, and antibacterial applications of covalent organic frameworks (COFs). COFs represent a distinct category of porous materials characterized by a blend of advantageous features, including customizable pore dimensions, substantial surface area, and adaptable chemical properties. These attributes position COFs as promising contenders for various applications, notably in the realm of antibacterial activity. COFs exhibit considerable potential in the domain of antibacterial applications, owing to their amenability to functionalization with antibacterial agents. The scientific community is actively exploring COFs that have been imbued with metal ions, such as copper or silver, given their observed robust antibacterial properties. These investigations strongly suggest that COFs could be harnessed effectively as potent antibacterial agents across a diverse array of applications. Finally, COFs hold immense promise as a novel class of materials for antibacterial applications, shedding light on the synthesis, characterization, and functionalization of COFs tailored for specific purposes. The potential of COFs as effective antibacterial agents beckons further exploration and underscores their potential to revolutionize antibacterial strategies in various domains.</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139669776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Localization and quantitative distribution of a chromatin structural protein Topoisomerase II on plant chromosome using HVTEM and UHVTEM","authors":"Channarong Sartsanga ,&nbsp;Rinyaporn Phengchat ,&nbsp;Toshiyuki Wako ,&nbsp;Kiichi Fukui ,&nbsp;Nobuko Ohmido","doi":"10.1016/j.micron.2024.103596","DOIUrl":"10.1016/j.micron.2024.103596","url":null,"abstract":"<div><p>Topoisomerase II (TopoII) is an essential structural protein of the metaphase chromosome. It maintains the axial compaction of chromosomes during metaphase. It is localized at the axial region of chromosomes and accumulates at the centromeric region in metaphase chromosomes. However, little is known about TopoII localization and distribution in plant chromosomes, except for several publications. We used high voltage transmission electron microscopy (HVTEM) and ultra-high voltage transmission electron microscopy (UHVTEM) in conjunction with immunogold labeling and visualization techniques to detect TopoII and investigate its localization, alignment, and density on the barley chromosome at 1.4 nm scale. We found that HVTEM and UHVTEM combined with immunogold labeling is suitable for the detection of structural proteins, including a single molecule of TopoII. This is because the average size of the gold particles for TopoII visualization after silver enhancement is 8.9 ± 3.9 nm, which is well detected. We found that 31,005 TopoII molecules are distributed along the barley chromosomes in an unspecific pattern at the chromosome arms and accumulate specifically at the nucleolus organizer regions (NORs) and centromeric region. The TopoII density were 1.32-fold, 1.58-fold, and 1.36-fold at the terminal region, at the NORs, and the centromeric region, respectively. The findings of TopoII localization in this study support the multiple reported functions of TopoII in the barley metaphase chromosome.</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139664013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A COMPARATIVE APPROACH EMPLOYING MICROCT FOR THE ANALYSIS OF CENOZOIC FORAMINIFERA FROM THE BRAZILIAN CARBONATE EQUATORIAL PLATFORM","authors":"Olga Oliveira De Araujo, Orangel Aguilera, Dayana Alvarado, B. Guimarães, V. Kutter, A. P. Linhares, Daniel Lima, Julianny dos Santos Silva, Ricardo Lopes","doi":"10.1016/j.micron.2024.103611","DOIUrl":"https://doi.org/10.1016/j.micron.2024.103611","url":null,"abstract":"","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139885144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measuring electrical properties in semiconductor devices by pixelated STEM and off-axis electron holography (or convergent beams vs. plane waves).","authors":"David Cooper ,&nbsp;Lucas Bruas ,&nbsp;Matthew Bryan ,&nbsp;Victor Boureau","doi":"10.1016/j.micron.2024.103594","DOIUrl":"10.1016/j.micron.2024.103594","url":null,"abstract":"<div><p>We demonstrate the use of both pixelated differential phase contrast (DPC) scanning transmission electron microscopy (STEM) and off-axis electron holography (EH) for the measurement of electric fields and assess the advantages and limitations of each technique when applied to technologically relevant samples. Three different types of samples are examined, firstly a simple highly-doped Si <em>pn</em> junction. Then a SiGe superlattice is examined to evaluate the effects of the mean inner potential on the measured signal. Finally, an InGaN/GaN microwire light-emitting diode (LED) device is examined which has a polarization field, variations of mean inner potential and a wurtzite crystal lattice. We discuss aspects such as spatial resolution and sensitivity, and the concept of pseudo-field is defined. However, the most important point is the need to limit the influence of diffraction contrast to obtain accurate measurements. In this respect, the use of a plane electron wave for EH is clearly beneficial when compared to the use of a convergent beam for pixelated DPC STEM.</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0968432824000118/pdfft?md5=f90ba147ad9c37d1f4da7a8d87ae9d60&pid=1-s2.0-S0968432824000118-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139657441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dimple Grinding Coupled with Optical Microscopy for Porosity Analysis of Metallic Coatings","authors":"H. Hu ,&nbsp;A. He ,&nbsp;D. Aasen ,&nbsp;S. Shukla ,&nbsp;D.G. Ivey","doi":"10.1016/j.micron.2024.103593","DOIUrl":"10.1016/j.micron.2024.103593","url":null,"abstract":"<div><p>Dimple grinding is one of the steps used in a common method of preparing samples for transmission electron microscopy (TEM); the TEM sample preparation process also involves ion beam sputtering after the dimpling stage. During dimpling, a spherical depression is machined into the sample, leaving a thicker rim to support and facilitate sample handling. In this paper, an alternative application for dimple grinding is developed; dimple grinding combined with optical microscopy is utilized to quantify internal porosity present within coatings. This technique essentially permits three dimensional porosity quantification across the coating thickness using a simple polishing method which provides analysis of areas larger than those observed during standard cross sectional microscopy. The application of this technique to nine electroless nickel-phosphorus (Ni-P) coatings deposited on Mg substrates is demonstrated. An analysis linking medium P content in the Ni-P coatings and high coating thickness to lower porosity is also performed. The lowest porosity was observed for medium P content coatings (5.2 wt% P), while the largest porosity occurred for the high P content coatings (10.0 wt% P). Porosity levels decreased continuously with increasing coating thickness (from 28 µm to 57 µm).</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0968432824000106/pdfft?md5=3bdf3d94a7ab2c02afc43aa20eb7231d&pid=1-s2.0-S0968432824000106-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139553819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A calculation approach for current density distribution evolution of secondary electrons using differential algebra method","authors":"Hangfeng Hu,&nbsp;Meishan Li,&nbsp;Jintao Hu,&nbsp;Fu Liu,&nbsp;Yongfeng Kang","doi":"10.1016/j.micron.2024.103592","DOIUrl":"10.1016/j.micron.2024.103592","url":null,"abstract":"<div><p>In this study, the concept of the current density distribution (CDD) evolution of secondary electron (SE) beam is presented, and a novel approach using the differential algebra<span> (DA) method is proposed to calculate the CDD evolution of the SE beam. Firstly, the emitted SE beam is divided into some beamlets in polar and azimuth angle directions. For each beamlet only one reference trajectory is traced using DA method. As a result, the transfer properties for this beamlet are obtained. Using the transfer properties, the current density function at arbitrary plane for the beamlet can be derived, in which the initial angle distribution, energy distribution and emission source size are considered. And then, the current density function is integrated, resulting in the CDD of this beamlet at arbitrary plane. Finally, the CDD evolution of the whole SE beam is obtained by superposing the CDDs of all beamlets. As an example, a SE detection system for a scanning electron microscope (SEM) is calculated using the proposed approach and therefore the SE CDD evolution is obtained and analyzed. Furthermore, experiments for observing the SE image of detector are performed, and the calculated SE CDD and the corresponding simulation images well explained the experimental results, validating the proposed calculation method. The proposed approach can be potentially applied for optimizing the SE detection system and therefore improving the collection efficiency of SE.</span></p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139510379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology of the male reproductive system and spermatozoa of Mahanarva fimbriolata (Stål, 1854) (Hemiptera: Cercopidae) with evidence of a spermatostyle in the sperm conjugation","authors":"Rômulo Fagundes Sodré ,&nbsp;Luci Boa Nova Coelho ,&nbsp;Paulo Henrique Rezende ,&nbsp;Dayvson Ayala Costa ,&nbsp;Glenda Dias ,&nbsp;José Lino-Neto","doi":"10.1016/j.micron.2024.103591","DOIUrl":"10.1016/j.micron.2024.103591","url":null,"abstract":"<div><p>Changes in harvesting methods in the early 1990s led to <em>Mahanarva fimbriolata</em> becoming the most prevalent pest in sugarcane plantations. Encouraged by the scarcity of research on the reproductive system and spermatology of Auchenorrhyncha, we provide a detailed description of the male reproductive system and spermatozoa of this cercopid. This will not only aid in taxonomic purposes but also help in understanding the reproductive biology of the species. The male reproductive system, spermatozoa, and sperm bundles of <em>M. fimbriolata</em><span> were investigated using light microscopy. Our results reveal a reproductive system consisting of a pair of testes, each with 36 follicles, two vasa deferentia, two well-developed seminal vesicles, a single pair of accessory glands, and an ejaculatory duct. Here, we also describe and explore the particularities of the formation of secondary sperm bundles, where cells interestingly bind only to the apical region of the spermatostyle. We also propose some possible benefits of this unusual organization for the reproductive success of the species.</span></p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139456157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uncovering hidden treasures: Mapping morphological changes in the differentiation of human mesenchymal stem cells to osteoblasts using deep learning","authors":"Faisal Quadri ,&nbsp;Mano Govindaraj ,&nbsp;Soja Soman ,&nbsp;Niti M. Dhutia ,&nbsp;Sanjairaj Vijayavenkataraman","doi":"10.1016/j.micron.2023.103581","DOIUrl":"10.1016/j.micron.2023.103581","url":null,"abstract":"<div><p>Deep Learning<span> (DL) is becoming an increasingly popular technology being employed in life sciences research due to its ability to perform complex and time-consuming tasks with significantly greater speed, accuracy, and reproducibility than human researchers – allowing them to dedicate their time to more complex tasks. One potential application of DL is to analyze cell images taken by microscopes. Quantitative analysis of cell microscopy images remain a challenge – with manual cell characterization requiring excessive amounts of time and effort. DL can address these issues, by quickly extracting such data and enabling rigorous, empirical analysis of images. Here, DL is used to quantitively analyze images of Mesenchymal Stem Cells (MSCs) differentiating into Osteoblasts (OBs), tracking morphological changes throughout this transition. The changes in morphology throughout the differentiation protocol provide evidence for a distinct path of morphological transformations that the cells undergo in their transition, with changes in perimeter being observable before changes in eceentricity. Subsequent differentiation experiments can be quantitatively compared with our dataset to concretely evaluate how different conditions affect differentiation and this paper can also be used as a guide for researchers on how to utilize DL workflows in their own labs.</span></p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139397732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of reinforcement learning applications in segmentation, chemotherapy, and radiotherapy of cancer","authors":"Rishi Khajuria,&nbsp;Abid Sarwar","doi":"10.1016/j.micron.2023.103583","DOIUrl":"10.1016/j.micron.2023.103583","url":null,"abstract":"<div><p>Owing to early diagnosis and treatment of cancer as a prerequisite in recent times, the role of machine learning has been increased substantially. The mathematically powerful and optimized solutions for the detection and cure of cancer are constantly being explored and novel models based upon standard algorithms are also being developed. Leveraging one such solution is Reinforcement Learning (RL), which is a semi-supervised type of learning. The paper presents a detailed discussion on the various RL techniques, algorithms, and open issues, in addition to the review of literature for diagnosis and treatment of cancer. A smaller number of publications for diagnosis and treatment of cancer have been reported before 2011 but now after the success of Deep Learning (DL) and the advent of Deep Reinforcement Learning (DRL), the publications have grown in number from 2017 onwards. The scope of RL for cancer diagnosis and treatment is also demystified and provides the research community with the insights of how to formulate RL problem as a Cancer diagnostic problem. RL has been found successful for landmark detection in medical images and optimal control of drugs and radiations.</p></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139036207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}