7,200 results on '"scanning"'
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52. Electron beam hardening of nanobainitic steel.
- Author
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Śliwiński, Piotr, Węglowski, Marek St, Wieczorek, Andrzej N., and Skołek, Emilia
- Abstract
Nanobainitic steels with high Si content are very promising materials due to the very favourable combination of mechanical and functional properties. However, sometimes in order to achieve the required results, it is necessary to further increase the surface's layer hardness. One of the feasible methods of surface hardening is electron beam hardening. In this work, 30 × 20 × 150 mm blocks made of nanobainitic steel were hardened using a defocused oscillating electron beam. Two methods of surface hardening were used – with movement of the sample relative to the heat source and hardening using only beam oscillation. The obtained samples were then subjected to light microscopic and scanning electron microscopic microstructure analysis as well as Vickers hardness testing. The average hardnesses of all hardened samples were in the range of 641–681 HV0.1 which means the surface hardening resulted in a hardness increase in the range of 239–279 HV0.1. The occurrence of similar hardening depths and hardness values in specimens hardened by both methods was an interesting phenomenon that was observed. The amount of energy input needed to achieve similar results was up to 35% less for the method without specimen movement. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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53. 一种跳转向量的隐性加权分数傅里叶变换通信方法.
- Author
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刘 芳, 黄珂婷, 侯 宇, and 冯永新
- Abstract
Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
54. A review of 70 years with astrometry: From meridian circles to Gaia and beyond.
- Author
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Høg, Erik
- Subjects
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HISTORY of astronomy , *ASTROPHYSICS , *PHOTOELECTRIC cells , *ASTRONOMY - Abstract
In 1953 I heard of an experiment in 1925 by Bengt Strömgren where he observed transit times with the meridian circle at the Copenhagen University Observatory measuring the current in a photocell behind slits when a star was crossing. In 1954 just 22 years old I was given the task as a student to make first test observations with a new meridian circle of the observatory. I became fascinated by the instrument and by the importance of astrometry for astronomy. Work at four meridian circles, two in Denmark, one in Hamburg, one in Lund, and Pierre Lacroute's vision of space astrometry in France had by 1973 created the foundation for development of the Hipparcos satellite, and Gaia followed. In 2013 I proposed a successor satellite which has gained momentum especially thanks to the efforts of David Hobbs and it has a good chance to be launched by ESA about 2045. – But 70 years ago, optical astrometry was considered a dying branch of astronomy, unattractive compared with astrophysics. The following growth built on the still active interest in astrometry in Europe in those years and it was supported by ESA, the European Space Agency. – This review is only about astrometry where I was personally involved. [ABSTRACT FROM AUTHOR]
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- 2024
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55. Using the Amsler Grid Test for Age-Related Macular Degeneration Screening.
- Author
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Kuzucu Üşümüş, Seyyide Ayşenur, Altıntaş, Ayşe Gül Koçak, Özdemir, Ayşe, and Aypak, Cenk
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BLINDNESS ,RETINAL degeneration ,ACQUISITION of data ,FAMILY health ,OPHTHALMOLOGISTS ,VISION testing ,PRIMARY health care ,COMPARATIVE studies ,VISUAL acuity ,MEDICAL records ,OPTICAL coherence tomography ,DESCRIPTIVE statistics ,SENSITIVITY & specificity (Statistics) - Abstract
Objectives: To evaluate the use of the Amsler grid test (AGT) in screening for age-related macular degeneration (AMD), one of the most common causes of blindness, in primary healthcare settings. Materials and Methods: The AGT was applied to 700 eyes of 355 people aged 50 and over who applied to a family health center in Ankara and had no eye complaints. The test was considered positive if the lines on the AGT card were seen as broken or curved, there was a difference in shape or size between the squares, or a color change or blurring was described in any area. An ophthalmologist was consulted if the AGT was positive in one or both eyes. Patients considered suitable by ophthalmologists were evaluated with optical coherence tomography. AGT results were compared with ophthalmologist examination and tomography findings in terms of AMD detection. Results: The AGT was positive in 97 (13.9%) and negative in 603 (86.1%) out of 700 eyes included in the study. A total of 184 eyes, 79 with a positive AGT and 105 eyes with a negative test, were evaluated by an ophthalmologist. As a result of examinations and tests performed by ophthalmologists, AMD was detected in a total of 67 eyes: 42 of 79 eyes with positive AGT and 25 of 105 eyes with negative AGT but referred to an ophthalmologist for different reasons. In our study, the AGT had 62.7% sensitivity and 68.4% specificity. Conclusion: The AGT is an inexpensive and easily applicable test. Although moderate sensitivity and specificity were found in our study; further studies are needed to evaluate the suitability of its use for AMD screening in primary care with limited facilities. [ABSTRACT FROM AUTHOR]
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- 2024
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56. Analysis of Methods for Measuring Parameters of the Radiation Pattern of Antenna Systems
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A. V. Sharamet and A. N. Lysy
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antenna measurements ,radiation pattern ,radiation zone ,radar station ,radio emission source ,detection zone ,flying around ,scanning ,Electronics ,TK7800-8360 - Abstract
Measuring the parameters of the antenna pattern is an urgent task in the development and operation of radio engineering systems. This problem can be solved by various methods of antenna measurements. In this case, depending on the radiation zone of the antenna, two main groups of measurement methods are distinguished: methods of direct measurements in the far-field and methods of reconstructive measurements in the near-field. Methods of antenna measurements in the far-field, which allow obtaining direct results, are the most developed and simple, since in the case of the far-field, the angular distribution of the field, regardless of distance, is characterized by a radiation pattern. Methods of the near-field are based on measuring the amplitude-phase distribution of the orthogonal components of the electromagnetic field in the near zone with subsequent recalculation of the parameters and restoration of the spatial radiation pattern of the antenna under study. The comparative analysis of the main groups of antenna measurement methods shows that at the present stage of their development, due to a number of advantages, measurement methods in the near-field with subsequent reconstruction of the radiation pattern of the studied antenna in the far-field are most widely used.
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- 2024
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57. Low-Cost Smartphone Photogrammetry Accurately Digitises Positive Socket and Limb Casts
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Sean Cullen, Ruth Mackay, Amir Mohagheghi, and Xinli Du
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prosthetics ,sockets ,scanning ,photogrammetry ,low cost ,digital twin ,Medicine - Abstract
Digitising prosthetic sockets and moulds is critical for advanced fabrication techniques enabling reduced lead times, advanced computer modelling, and personalised design history. Current 3D scanners are expensive (>GBP 5000) and difficult to use, restricting their use by prosthetists. In this paper, we explore the use and accuracy of smartphone photogrammetry (
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- 2023
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58. A Design Proposal Using Coherently Radiating Periodic Structures (CORPSs) for 2-D Phased Arrays of Limited Scanning
- Author
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Gilberto Calvillo, Marco A. Panduro, Elizvan Juarez, Alberto Reyna, and Carlos del Rio
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2-D phased array ,scanning ,CORPS ,phase shifters ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
New configurations of 2-D phased arrays are proposed in this paper for reducing the number of phase shifters. This design methodology is based on the use of a novel coherently radiating periodic structures (CORPSs) block for 2-D phased arrays. Two new antenna systems for 2-D phased arrays are studied and analyzed utilizing the CORPSs blocks of four inputs and nine outputs. These CORPSs feeding blocks are applied in a smart way to feed the planar antenna arrays by generating the required phase plane and reducing the number of control ports. Interesting results are provided based on the experimental measurements and full-wave simulations. These results illustrate a great reduction of the active devices (phase shifters), providing a good design compromise in terms of the scanning range and side lobe level performance. Furthermore, the provided results illustrate a maximum reduction capability in the number of phase shifters of 81%, considering a scanning range of ±30° in azimuth and ±30° in elevation. A raised cosine distribution is applied to reach side lobe levels of −19 dB for ±18° and −17 dB for ±30° in elevation. These benefits could be of interest to designers of phased antenna systems.
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- 2024
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59. Benchmarking the ideal sample thickness in cryo-EM
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Martynowycz, Michael W, Clabbers, Max TB, Unge, Johan, Hattne, Johan, and Gonen, Tamir
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Animals ,Benchmarking ,Cryoelectron Microscopy ,Crystallization ,Crystallography ,Electrons ,Humans ,Microscopy ,Electron ,Scanning ,Microscopy ,Electron ,Transmission ,Models ,Molecular ,Specimen Handling ,Cryo-EM ,MicroED ,FIB milling ,electron scattering ,mean free path - Abstract
The relationship between sample thickness and quality of data obtained is investigated by microcrystal electron diffraction (MicroED). Several electron microscopy (EM) grids containing proteinase K microcrystals of similar sizes from the same crystallization batch were prepared. Each grid was transferred into a focused ion beam and a scanning electron microscope in which the crystals were then systematically thinned into lamellae between 95- and 1,650-nm thick. MicroED data were collected at either 120-, 200-, or 300-kV accelerating voltages. Lamellae thicknesses were expressed in multiples of the corresponding inelastic mean free path to allow the results from different acceleration voltages to be compared. The quality of the data and subsequently determined structures were assessed using standard crystallographic measures. Structures were reliably determined with similar quality from crystalline lamellae up to twice the inelastic mean free path. Lower resolution diffraction was observed at three times the mean free path for all three accelerating voltages, but the data quality was insufficient to yield structures. Finally, no coherent diffraction was observed from lamellae thicker than four times the calculated inelastic mean free path. This study benchmarks the ideal specimen thickness with implications for all cryo-EM methods.
- Published
- 2021
60. Fen Eğitiminde Öğrenme Döngüsü Modeli Üzerine Yapılan Çalışmaların Analizi: Bir Meta-Sentez Çalışması
- Author
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Süleyman Yaman and Şadiye Karaşah Çakıcı
- Subjects
learning cycle model ,science education ,meta-synthesis ,scanning ,fen eğitimi ,meta-sentez ,öğrenme döngüsü ,tarama ,Education (General) ,L7-991 - Abstract
Türkiye'de öğrenme döngüsü modeli ile yapılmış çok sayıda çalışma bulunmaktadır. Bu modelle yürütülen çalışmaların içerikleri çoğunlukla nicel yöntemlerle analiz edilmiş ancak nitel araştırmalarda ortaya çıkan anlayışların, birikimine ve sentezine yönelik yürütülmüş çalışmaların sınırlı düzeyde olduğu tespit edilmiştir. Bu araştırma, fen eğitiminde öğrenme döngüsü modeliyle yapılan çalışmaların incelendiği bir meta-sentez çalışmasıdır. Bu amaçla, araştırmaya 37 çalışma dâhil edilmiş ve bu çalışmalar literatür destekli üç boyut ve üç boyuta bağlı altı tema içinde sentezlenmiştir. Oluşturulan boyutlar; ‘Öğrenme Döngüsü ve Etkileri’, ‘Öğrenme Döngüsü ve Öğrenme Alanı’, ve ‘Öğrenme Döngüsü ve Çalışma Grubu’ şeklinde belirlenmiştir. Belirtilen bu boyutlar doğrultusunda temalar oluşturulmuştur. Temalar sırasıyla; ‘Öğrenme döngüsünün avantajları’, ‘Öğrenme döngüsünün dezavantajları’, ‘Öğrenme döngüsü ve bilişsel alan’, ‘Öğrenme döngüsü ve duyuşsal alan’, ‘Öğrenme döngüsü ve devinişsel alan’, ‘Öğrenme döngüsü ve öğretmen’, ‘Öğrenme döngüsü ve öğretmen adayı’ ve ‘Öğrenme döngüsü ve öğrenci’ şeklindedir. Araştırıma bulgularına göre öğrenme döngüsü modelinin; öğrencilerin olumlu yönde tutum geliştirmelerine, tüm öğrenme alanlarında kazanımlar edinmelerine ve kavram yanılgılarının belirlenmesi ve giderilmesine katkı sağladığı tespit edilmiştir. Bu temalar doğrultusunda araştırma sonucunda, öğretmenlere, öğretmen adaylarına, araştırmacılara ve diğer ilgililere çeşitli öneriler sunulmuştur.
- Published
- 2023
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61. Effects of beam scanning modes on ion-irradiated iron microstructure
- Author
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T. Dunatov, M. Roldan, and T. Tadić
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Ion beam irradiation ,Scanning ,Dose rate ,Void formation ,Iron ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Neutron induced damage in future nuclear materials can be studied using heavy ion beams only if the differences in the microstructure evolution are well understood. Large variations in the damage dose rate, caused by scanning of the ion beam, can alter the microstructure compared to steady-state irradiation. We study the effect of scanning on the microstructure by irradiating pure iron with a 10 MeV Fe ion beam to a dose of 0.2 dpa. The beam is scanned in one direction with frequencies of 200 Hz and 10 kHz. Different shapes of the beam are also used to study the effect of dose variation. All of the irradiations are conducted at room temperature using the DiFU chamber at RBI. TEM analysis shows differences between the narrow beam and defocused irradiation modes, including unusual void formation observed at 10 kHz. A wider beam reduces the effect of scanning speed and no voids are found in this scanning case.
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- 2024
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62. METASPLOIT FRAMEWORK АРҚЫЛЫ ЖЕЛІ МЕН СЕРВЕРДЕГІ ОСАЛДЫҚТАРДЫ СКАНЕРЛЕУ ЖӘНЕ ОПЕРАЦИЯЛЫҚ ЖҮЙЕЛЕРГЕ ҚАШЫҚТАН ҚОЛ ЖЕТКІЗУ
- Author
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Бидахмет, Ж., Уайда, А., Майлыбаева, А. Д., Даркенбаев, Д. К., Бекназаров, С., and Бағдаулет, Д.
- Abstract
This article discusses and describes in detail one example of an information security audit. The work was done in practice using applications. The main focus for audit tools was on the Kali Linux operating system and the study of their important role in ensuring network security in the modern information society. In addition, the article provides an overview of the key stages of an information security audit, starting from defining the goals of the study to analyzing the results and formulating recommendations. The main tools and technologies used in the audit process are also considered, which contributes to expanding knowledge in the field of cybersecurity and improving the quality of audit. The article additionally describes an effective example for those who are interested in the field of information security for research work. [ABSTRACT FROM AUTHOR]
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- 2024
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63. Synthesis, characterization and protection effect of black rice anthocyanins nano-composite against hepatotoxicity induced by methotrexate in rats.
- Author
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Sheikha, M. A., Soheir, N. A., and SyragEldin, F. M.
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BLOOD lipids ,METHOTREXATE ,INFRARED spectroscopy ,SILVER ions ,HEPATOTOXICOLOGY ,ASPARTATE aminotransferase - Abstract
Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
64. A Computed Tomography–Based Fracture Prediction Model With Images of Vertebral Bones and Muscles by Employing Deep Learning: Development and Validation Study.
- Author
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Kong, Sung Hye, Cho, Wonwoo, Park, Sung Bae, Choo, Jaegul, Kim, Jung Hee, Kim, Sang Wan, and Shin, Chan Soo
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ARTIFICIAL neural networks ,TYPE 2 diabetes ,MUSCLE aging ,VERTEBRAL fractures ,HIP fractures - Abstract
Background: With the progressive increase in aging populations, the use of opportunistic computed tomography (CT) scanning is increasing, which could be a valuable method for acquiring information on both muscles and bones of aging populations. Objective: The aim of this study was to develop and externally validate opportunistic CT-based fracture prediction models by using images of vertebral bones and paravertebral muscles. Methods: The models were developed based on a retrospective longitudinal cohort study of 1214 patients with abdominal CT images between 2010 and 2019. The models were externally validated in 495 patients. The primary outcome of this study was defined as the predictive accuracy for identifying vertebral fracture events within a 5-year follow-up. The image models were developed using an attention convolutional neural network–recurrent neural network model from images of the vertebral bone and paravertebral muscles. Results: The mean ages of the patients in the development and validation sets were 73 years and 68 years, and 69.1% (839/1214) and 78.8% (390/495) of them were females, respectively. The areas under the receiver operator curve (AUROCs) for predicting vertebral fractures were superior in images of the vertebral bone and paravertebral muscles than those in the bone-only images in the external validation cohort (0.827, 95% CI 0.821-0.833 vs 0.815, 95% CI 0.806-0.824, respectively; P <.001). The AUROCs of these image models were higher than those of the fracture risk assessment models (0.810 for major osteoporotic risk, 0.780 for hip fracture risk). For the clinical model using age, sex, BMI, use of steroids, smoking, possible secondary osteoporosis, type 2 diabetes mellitus, HIV, hepatitis C, and renal failure, the AUROC value in the external validation cohort was 0.749 (95% CI 0.736-0.762), which was lower than that of the image model using vertebral bones and muscles (P <.001). Conclusions: The model using the images of the vertebral bone and paravertebral muscle showed better performance than that using the images of the bone-only or clinical variables. Opportunistic CT screening may contribute to identifying patients with a high fracture risk in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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65. USING REVERSE ENGINEERING TECHNIQUES IN WEAR IDENTIFICATION OF THE NEEDLE PLATE OF SEWING MACHINE.
- Author
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Darius, ŞUTEU Marius, Marius, BABAN, and Florin, BABAN Calin
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SEWING machines ,REVERSE engineering ,NEEDLES & pins ,POINT cloud ,TEXTILE products ,TECHNICAL textiles - Abstract
Reverse engineering techniques were employed in this study to determine the wear of needle plates of sewing machines. The wear of such components used in the sewing process of textile products has the effect of bending them. Due to this phenomenon, the sewing needles hit the edges of the hole of the needle plates that leads to their break. As a result of this process the needle plate wears out. The wear of needle plates is manifested by the formation of micro-irregularities on the contour of the hole on the needle plate. Reverse engineering techniques allow to determine the size of the micro-irregularities that comes out on the contour of the hole on the needle plate. In order to apply reverse engineering techniques to establish the degree of wear of a needle plate, the plate was scanned using the Shining 3D scanner and the points cloud of the needle plate were obtained. The points cloud was then transferred to the Shining Form XOR redesign software, which allows making sections throughout the needle plate. The section where the micro-irregularities have the maximum size was determined, and through the facilities offered by the Shining Form XOR software the value of the micro-irregularities related to the state of wear of the needle plates was established. [ABSTRACT FROM AUTHOR]
- Published
- 2024
66. Guidelines for interpreting the results of bibliometric analysis: A sensemaking approach.
- Author
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Lim, Weng Marc and Kumar, Satish
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BIBLIOMETRICS ,RESEARCH personnel - Abstract
While bibliometric analysis is inherently quantitative and objective, it necessitates interpretation, thereby introducing an element of subjectivity. This article proposes a sensemaking approach that transitions researchers from mere description to proactive interpretation of bibliometric results, transforming raw information into informed insights. We discuss the applicability of sensemaking in bibliometric analysis and offer practical guidelines for its integration into systematic literature reviews. These guidelines revolve around a three‐stage sensemaking process—that is, scanning, sensing, and substantiating—each crucial to deriving meaningful interpretations. As such, this article serves as a valuable guide for researchers seeking to utilize bibliometric analysis as a potent analytical tool in their review studies. [ABSTRACT FROM AUTHOR]
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- 2024
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67. Automated Eddy Current System for Aircraft Structure Inspection.
- Author
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Lysenko, Iuliia, Kuts, Yurii, Petryk, Valentyn, Malko, Volodymyr, and Melnyk, Andrii
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NONDESTRUCTIVE testing ,EDDY currents (Electric) ,SIGNAL processing ,AUTOMATION ,ALGORITHMS - Abstract
Aircraft part diagnostics are crucial during both production and maintenance, with eddy current nondestructive testing (ECNDT) being the method of choice due to its cost-effectiveness, informativeness, productivity, and reliability. ECNDT excels regardless of surface condition or coatings. It's employed for diagnosing various aircraft components, necessitating diverse transducer types, excitation modes, and advanced signal processing. To improve ECNDT, this article explores integrating harmonic and impulse excitation modes in a single tool to enhance informativeness. Building upon a wireless eddy current system, the authors propose a comprehensive method for processing and displaying information suitable for object condition monitoring systems. The system includes automated transducer mode control and experimental data processing algorithms. The constant expansion of tested objects and new materials underscores the need to enhance the theoretical foundations of eddy current non-destructive testing, refine signal processing techniques, and identify informative signs. This demands the development of new automated ECNDT tools, and this article offers a promising avenue for improvement. The results include model and experimental tests of system components, showcasing the potential of this approach to enhance ECNDT effectiveness, automation, and informativeness in the realm of aircraft part diagnostics. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
68. Case Report and X-ray Microtomography and Scanning Electron Microscopy Analysis of Teeth with Hypocalcified Amelogenesis Imperfecta.
- Author
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Marinoni, Rodrigo W., Silva, Thiago G., Benato, Leonardo S., Rumbelsperger, Anelize M. B., and Soares de Lima, Antonio Adilson
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AMELOGENESIS imperfecta ,X-ray computed microtomography ,SCANNING electron microscopy ,TEETH ,DENTAL enamel ,TOOTH erosion ,TOOTH demineralization - Abstract
Amelogenesis imperfecta (AI) is a genetic disease characterized by producing morphological and structural changes in tooth enamel. Objective: To highlight the morphological changes observed in teeth with hypocalcified AI based on scanning electron microscopy and microtomography analysis. Case report: An adult male had teeth seriously compromised by hypocalcified AI. The treatment plan involved removal of third molars followed by restorative and prosthetic treatment. After extraction, the teeth were analyzed by SEM and X-ray microtomography (microCT). Teeth with AI revealed the presence of microfractures arranged from the outer surface to the center of the enamel. Microfractures had a cracked or "cracked ground" pattern. SEM confirmed the presence of microfractures and distortion in the orientation of the enamel prisms in some regions. Conclusion: Teeth of patients with hypocalcified amelogenesis imperfecta IIIA subtype show significant structural changes that are closely related with the ease of fractures. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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69. Leukocyte- and Platelet-Rich Fibrin (L-PRF) Obtained from Smokers and Nonsmokers Shows a Similar Uniaxial Tensile Response In Vitro.
- Author
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Lara, Cesar, Bezmalinovic, Alejandro, García-Herrera, Claudio, Ríos, Susana, Valenzuela, Loreto M., and Martínez, Constanza E.
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PLATELET-rich fibrin ,NON-smokers ,SCANNING electron microscopes ,WOUND healing - Abstract
We evaluated and compared the biomechanical properties of Leukocyte-and Platelet Rich Fibrin L-PRF clots and membranes derived from smoker and nonsmoker donors. Twenty venous-blood donors (aged 18 to 50 years) were included after signing informed consent forms. L-PRF clots were analyzed and then compressed to obtain L-PRF membranes. L-PRF clot and membrane samples were tested in quasi-static uniaxial tension and the stress–stretch response was registered and characterized. Furthermore, scanning electron microscope representative images were taken to see the fibrin structure from both groups. The analysis of stress–stretch curves allowed us to evaluate the statistical significance in differences between smoker and nonsmoker groups. L-PRF membranes showed a stiffer response and higher tensile strength when compared to L-PRF clots. However, no statistically significant differences were found between samples from smokers and nonsmokers. With the limitations of our in vitro study, we can suggest that the tensile properties of L-PRF clots and membranes from the blood of smokers and nonsmokers are similar. More studies are necessary to fully characterize the effect of smoking on the biomechanical behavior of this platelet concentrate, to further encourage its use as an alternative to promote wound healing in smokers. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
70. Low-Cost Smartphone Photogrammetry Accurately Digitises Positive Socket and Limb Casts.
- Author
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Cullen, Sean, Mackay, Ruth, Mohagheghi, Amir, and Du, Xinli
- Subjects
ARTIFICIAL limbs ,COMPUTER software ,ORTHOPEDIC casts ,DIGITAL technology ,SMARTPHONES ,PHOTOGRAMMETRY ,RESEARCH funding ,ALGORITHMS - Abstract
Digitising prosthetic sockets and moulds is critical for advanced fabrication techniques enabling reduced lead times, advanced computer modelling, and personalised design history. Current 3D scanners are expensive (>GBP 5000) and difficult to use, restricting their use by prosthetists. In this paper, we explore the use and accuracy of smartphone photogrammetry (
- Published
- 2023
- Full Text
- View/download PDF
71. Strategies for highlighting items within visual scene displays to support augmentative and alternative communication access for those with physical impairments.
- Author
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Pitt, Kevin M. and McCarthy, John. W.
- Subjects
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ART , *FACILITATED communication , *SOCIAL support , *MOTION pictures , *RESEARCH methodology , *INTERVIEWING , *DIAGNOSTIC imaging , *VISUAL perception , *COMMUNICATION devices for people with disabilities , *PHOTOGRAPHY , *ARTISTS , *DESCRIPTIVE statistics , *RESEARCH funding , *THEMATIC analysis , *COLOR - Abstract
In contrast to the traditional grid-based display, visual scene displays (VSDs) offer a new paradigm for aided communication. For individuals who cannot select items from an AAC display by direct selection due to physical impairments, AAC access can be supported via methods such as item scanning. Item scanning sequentially highlights items on a display until the individual signals for selection. How items are highlighted or scanned for AAC access can impact performance outcomes. Further, the effectiveness of a VSD interface may be enhanced through consultation with experts in visual communication. Therefore, to support AAC access for those with physical impairments, the aim of this study was to evaluate the perspectives of experts in visual communication regarding effective methods for highlighting VSD elements. Thirteen participants with expertise related to visual communication (e.g., photographers, artists) completed semi-structured interviews regarding techniques for item highlighting. Study findings identified four main themes to inform how AAC items may be highlighted or scanned, including (1) use of contrast related to light and dark, (2) use of contrast as it relates to colour, (3) outline highlighting, and (4) use of scale and motion. By identifying how compositional techniques can be utilized to highlight VSD elements, study findings may inform current practice for scanning-based AAC access, along with other selection techniques where feedback or highlighting is used (e.g., eye-gaze, brain-computer interface). Further, avenues for just-in-time programming are discussed to support effective implementation for those with physical impairments. Findings identify multiple potential techniques to improve scanning through items in a photograph for individuals with severe motor impairments using alternative access strategies. Study findings inform current practice for scanning-based AAC access, along with other selection techniques where feedback or highlighting is used (e.g., eye-gaze, brain-computer interface). Avenues for just in time programming of AAC displays are discussed to decrease programming demands and support effective implementation of study findings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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72. Numerical and physical modeling of breast cancer based on image fusion and artificial intelligence.
- Author
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Dołęga-Kozierowski, Bartosz, Kasprzak, Piotr, Lis, Michał, Szynglarewicz, Bartłomiej, Matkowski, Rafał, Sawicki, Marek, Dymek, Mateusz, Szumiejko, Adrianna, Carmo, Gustavo, Kwiatkowski, Artur, Soliński, Daniel Grzegorz, and Ptak, Mariusz
- Abstract
Purpose: The key problem raised in the paper is the change in the position of the breast tumor due to magnetic resonance imaging examinations in the abdominal position relative to the supine position during the surgical procedure. Changing the position of the patient leads to significant deformation of the breast, which leads to the inability to indicate the location of the neoplastic lesion correctly. Methods: This study outlines a methodological process for treating cancer patients. Pre-qualification assessments are conducted for magnetic resonance imaging (MRI), and 3D scans are taken in three positions: supine with arms raised, supine surgical position (SS), and standing. MRI and standard ultrasonography (USG) imaging are performed, and breast and cancer tissue are segmented from the MRI images. Finite element analysis is used to simulate tissue behavior in different positions, and an artificial neural network is trained to predict tumor dislocation. Based on the model, a 3D-printed breast with a highlighted tumor is manufactured. This computer-aided analysis is used to create a detailed surgical plan, and lumpectomy surgery is performed in the SS. In addition, the geometry of the tumor is presented to the medical staff as a 3D-printed element. Results: By utilizing a comprehensive range of techniques, including pre-qualification assessment, 3D scanning, MRI and USG imaging, segmentation of breast and cancer tissue, model analysis, image fusion, finite element analysis, artificial neural network training, and additive manufacturing, a detailed surgical plan can be created for performing lumpectomy surgery in the supine surgical position. Conclusion: The new approach developed for the pre-operative assessment and surgical planning of breast cancer patients has demonstrated significant potential for improving the accuracy and efficacy of surgical procedures. This procedure may also help the pathomorphological justification. Moreover, transparent 3D-printed breast models can benefit breast cancer operation assistance. The physical and computational models can help surgeons visualize the breast and the tumor more accurately and detailedly, allowing them to plan the surgery with greater precision and accuracy. [ABSTRACT FROM AUTHOR]
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- 2023
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73. Comparing the Methods of Terrestrial Laser Scanning and Photogrammetry for the Geometric Documentation of Stone Bridges Through the Case Study of Tzelefos Bridge
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Fellas, A., Demosthenous, M., Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Moropoulou, Antonia, editor, Georgopoulos, Andreas, editor, Ioannides, Marinos, editor, Doulamis, Anastasios, editor, Lampropoulos, Kyriakos, editor, and Ronchi, Alfredo, editor
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- 2023
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74. Reconstruction of a Botanical Tree from a 3D Point Cloud
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Bærentzen, J. Andreas, Villesen, Ida Bukh, Dellwik, Ebba, Alberti, Giovanni, Series Editor, Patrizio, Giorgio, Editor-in-Chief, Bracci, Filippo, Series Editor, Canuto, Claudio, Series Editor, Ferone, Vincenzo, Series Editor, Fontanari, Claudio, Series Editor, Moscariello, Gioconda, Series Editor, Pistoia, Angela, Series Editor, Sammartino, Marco, Series Editor, Cristiani, Emiliano, editor, Falcone †, Maurizio, editor, and Tozza, Silvia, editor
- Published
- 2023
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75. Digital Twins and Their Roles in Building Deep Renovation Life Cycle
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Pan, Yuandong, Hu, Zhiqi, Brilakis, Ioannis, Lynn, Theo, Series Editor, Rosati, Pierangelo, Series Editor, Kassem, Mohamad, editor, Krinidis, Stelios, editor, and Kennedy, Jennifer, editor
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- 2023
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- View/download PDF
76. Applications of Foresight for Defence and Security: The Future of Crime
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Van Dasselaar, Tasha, Giddings, Jason, Stewart, Sydney, Masys, Anthony J., Editor-in-Chief, Bichler, Gisela, Advisory Editor, Bourlai, Thirimachos, Advisory Editor, Johnson, Chris, Advisory Editor, Karampelas, Panagiotis, Advisory Editor, Leuprecht, Christian, Advisory Editor, Morse, Edward C., Advisory Editor, Skillicorn, David, Advisory Editor, and Yamagata, Yoshiki, Advisory Editor
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- 2023
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77. IR Detectors Array
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Korotcenkov, Ghenadii and Korotcenkov, Ghenadii, editor
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- 2023
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78. Lipid membranes induce structural conversion from amyloid oligomers to fibrils
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Gu, Lei and Guo, Zhefeng
- Subjects
Biochemistry and Cell Biology ,Biological Sciences ,Neurodegenerative ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Aging ,Acquired Cognitive Impairment ,Dementia ,Neurosciences ,Brain Disorders ,Alzheimer's Disease ,Aetiology ,2.1 Biological and endogenous factors ,Neurological ,Alzheimer Disease ,Amyloid ,Amyloid beta-Peptides ,Amyloidogenic Proteins ,Amyloidosis ,Cell Membrane ,Electron Spin Resonance Spectroscopy ,Humans ,Liposomes ,Membrane Lipids ,Microscopy ,Electron ,Scanning ,Protein Multimerization ,Alzheimer's disease ,Protein aggregation ,Liposome ,Amyloid fibrils ,A beta oligomers ,Alzheimer’s disease ,Aβ oligomers ,Medicinal and Biomolecular Chemistry ,Medical Biochemistry and Metabolomics ,Biochemistry & Molecular Biology ,Biochemistry and cell biology ,Medicinal and biomolecular chemistry - Abstract
Formation of amyloid oligomers and fibrils underlies the pathogenesis of a number of neurodegenerative diseases such as Alzheimer's. One mechanism of action by which Aβ aggregates cause neuronal toxicity is through interactions with cellular membranes. Aβ aggregates have been shown to disrupt membrane integrity via pore formation, membrane thinning, or lipid extraction. At the same time, lipid membranes also affect the rate of Aβ aggregation and remodel pre-formed Aβ fibrils. Here we show that Aβ42 globulomers, a type of well-characterized and stable Aβ oligomers, convert to amyloid fibrils in the presence of DOPC liposomes. Electron paramagnetic resonance studies show that the fibrils converted from Aβ42 globulomers adopt the same structure as fibrils formed directly from monomers. Our results suggest that the interactions between Aβ oligomers and cellular membranes are dynamic. By converting Aβ oligomers to fibrils, the lipid membrane can reduce the membrane-disrupting activities caused by these oligomers. Modulation of Aβ-membrane interactions as a therapeutic strategy should take into account the dynamic nature of these interactions.
- Published
- 2021
79. Arrhythmogenicity of anti-tachycardia pacing in patients with implantable cardioverter defibrillator
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Sherien Samy Awad, Emmanuel Fares Azeez, Mohamed Ossama Taha, Wael Mohamed El-Naggar, and Ahmed El-Damaty
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ATP therapy ,VT acceleration ,Ramp ,Scanning ,Ventricular tachycardia ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Anti-tachycardia pacing therapy (ATP) has shown comparable efficacy to shock therapy in ventricular tachycardia (VT) termination with better quality of life. However, some ATPs may lead to VT acceleration or degeneration to ventricular fibrillation (VF), which will result in more ICD shocks. The aim of this study was to investigate the predictors of VT acceleration by ATP therapy in a real-life patient cohort. Results We retrospectively reviewed 448 monomorphic VT episodes that required ATP therapy in 60 patients with structural heart diseases implanted with ICD or CRTD. The clinical data of the patients and the episodes’ details were evaluated. We found that patients with a higher ejection fraction (EF) were more likely to be cardioverted by ATP therapy (P: 0.024). VT acceleration was more frequent in patients with lower EF (mean 31.24 ± 4.08) compared with the non-accelerated patients with higher EF (mean 37.00 ± 9.4, P: 0.016). The percentage of accelerated episodes was 8.5%. VT episodes with a mean cycle length (CL)
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- 2023
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80. Parathyroid adenoma: multimodal diagnosis capabilities: A retrospective study
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Nikolai A. Ognerubov, Tatiana S. Antipova, and Galina N. Abakumova
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parathyroid glands ,primary hyperparathyroidism ,adenoma ,diagnosis ,scanning ,single-photon emission computed tomography ,single-photon emission computed tomography combined with computed tomography ,positron emission tomography combined with computed tomography ,Medicine (General) ,R5-920 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background. Primary hyperparathyroidism is a common endocrinological disease caused mainly by parathyroid adenoma. The main treatment method is surgery (parathyroidectomy). Therefore, the exact determination of adenoma localization is crucial. Aim. To evaluate the current possibilities of multimodal diagnosis of parathyroid adenomas. Materials and methods. A retrospective analysis of 49 patients with primary hyperparathyroidism aged 24 to 82 (median 57.9 years) was performed. Modern radionuclide and hybrid technologies were used for topical diagnosis and metabolic assessment of parathyroid adenomas: scanning, single-photon emission computed tomography, single-photon emission computed tomography combined with computed tomography, positron emission tomography combined with computed tomography with 18F-deoxyglucose and 18F-choline. The diagnosis of primary hyperparathyroidism was confirmed by a biochemical blood test: the level of parathyroid hormone and ionized and total calcium. Results. The study included 43 (87.8%) females and 6 (12.2%) males. The female/male ratio was 7.2:1. Most cases (78.1%) were the hypercalcemic type of primary hyperparathyroidism, and the normocalcemic type was diagnosed in 21.9% of patients. The mean parathyroid hormone level was 145.43 pg/mL, exceeding the reference values by 2.2 times. Parathyroid hormone concentration in patients with primary hyperparathyroidism was 156.38 pg/mL, and mean ionized and total blood calcium levels were 1.43 and 3.04 mmol/L, respectively. The asymptomatic type occurred in 76.7% of patients. The symptomatic type of hyperparathyroidism had 23.3%, manifested with nephrolithiasis, pancreatitis, and bone lesions. Parathyroid adenomas were more often located in the left lobe (42.9%). In 77.6% of patients with primary hyperparathyroidism, solitary adenomas were detected. Ectopia of the parathyroid glands was detected in 16.3% of patients, with intrathyroidal location in the left lobe being the most common. Rare locations include the anterior and posterior mediastinum and the esophageal wall. Conclusion. Modern diagnostic multimodal options based on radionuclide and hybrid technologies are crucial in the personalized treatment of primary hyperparathyroidism.
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- 2023
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81. Spatially explicit depiction of a floral epiphytic bacterial community reveals role for environmental filtering within petals
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Hayes, Rebecca A, Rebolleda‐Gómez, Maria, Butela, Kristen, Cabo, Leah F, Cullen, Nevin, Kaufmann, Nancy, O'Neill, Steffani, and Ashman, Tia‐Lynn
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Aetiology ,2.2 Factors relating to the physical environment ,Bacteria ,Ecosystem ,Flowers ,Helianthus ,Microbiota ,Microscopy ,Electron ,Scanning ,Plants ,Radiation Tolerance ,Ultraviolet Rays ,Verbesina ,Helianthus tuberosus ,Verbesina alternifolia ,Anthosphere ,community ecology ,plant microbiome ,spatial structure ,Microbiology - Abstract
The microbiome of flowers (anthosphere) is an understudied compartment of the plant microbiome. Within the flower, petals represent a heterogeneous environment for microbes in terms of resources and environmental stress. Yet, little is known of drivers of structure and function of the epiphytic microbial community at the within-petal scale. We characterized the petal microbiome in two co-flowering plants that differ in the pattern of ultraviolet (UV) absorption along their petals. Bacterial communities were similar between plant hosts, with only rare phylogenetically distant species contributing to differences. The epiphyte community was highly culturable (75% of families) lending confidence in the spatially explicit isolation and characterization of bacteria. In one host, petals were heterogeneous in UV absorption along their length, and in these, there was a negative relationship between growth rate and position on the petal, as well as lower UV tolerance in strains isolated from the UV-absorbing base than from UV reflecting tip. A similar pattern was not seen in microbes isolated from a second host whose petals had uniform patterning along their length. Across strains, the variation in carbon usage and chemical tolerance followed common phylogenetic patterns. This work highlights the value of petals for spatially explicit explorations of bacteria of the anthosphere.
- Published
- 2021
82. UiO-66-NH2 and Zeolite-Templated Carbon Composites for the Degradation and Adsorption of Nerve Agents
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Lee, Jaeheon, Ka, Dongwon, Jung, Heesoo, Cho, Kyeongmin, Jin, Youngho, and Kim, Minkun
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Chemical Sciences ,Physical Chemistry ,Adsorption ,Carbon ,Metal-Organic Frameworks ,Microscopy ,Electron ,Scanning ,Nerve Agents ,Organometallic Compounds ,Phthalic Acids ,Porosity ,Sarin ,Soman ,Spectroscopy ,Fourier Transform Infrared ,Water ,X-Ray Diffraction ,Zeolites ,UiO-66-NH2 ,ZTC composite ,metal-organic framework ,zeolite-templated carbon ,nerve agent ,soman ,sarin ,UiO-66-NH2/ZTC composite ,Medicinal and Biomolecular Chemistry ,Organic Chemistry ,Theoretical and Computational Chemistry ,Medicinal and biomolecular chemistry ,Organic chemistry - Abstract
Composites of metal-organic frameworks and carbon materials have been suggested to be effective materials for the decomposition of chemical warfare agents. In this study, we synthesized UiO-66-NH2/zeolite-templated carbon (ZTC) composites for the adsorption and decomposition of the nerve agents sarin and soman. UiO-66-NH2/ZTC composites with good dispersion were prepared via a solvothermal method. Characterization studies showed that the composites had higher specific surface areas than pristine UiO-66-NH2, with broad pore size distributions centered at 1-2 nm. Owing to their porous nature, the UiO-66-NH2/ZTC composites could adsorb more water at 80% relative humidity. Among the UiO-66-NH2/ZTC composites, U0.8Z0.2 showed the best degradation performance. Characterization and gas adsorption studies revealed that beta-ZTC in U0.8Z0.2 provided additional adsorption and degradation sites for nerve agents. Among the investigated materials, including the pristine materials, U0.8Z0.2 also exhibited the best protection performance against the nerve agents. These results demonstrate that U0.8Z0.2 has the optimal composition for exploiting the degradation performance of pristine UiO-66-NH2 and the adsorption performance of pristine beta-ZTC.
- Published
- 2021
83. Scanning electron microscopy assessment of tubular penetration depth of root canal sealers combined with different obturation techniques.
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Cvjetićanin, Milica, Ramić, Bojana, Vukoje, Karolina, Drobac, Milan, Stojanac, Igor, and Petrović, Ljubomir
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- *
PIT & fissure sealants (Dentistry) , *SCANNING electron microscopy , *DENTINAL tubules , *MOLARS , *ROOT canal treatment - Abstract
Background/Aim. The ability to effectively and consistently penetrate dentinal tubules is considered a favorable factor for the evaluation of root canal sealers (RCSs). The aim of the study was to assess the penetration depth into dentinal tubules of three RCSs combined with four obturation techniques. Methods. The mesial canals of 66 extracted human mandibular molars were endodontically prepared and randomly allocated into 12 experimental groups depending on the RCS type used (AH Plus™, EndoREZ™, Sealapex™) as well as the obturation technique applied [cold lateral compaction, cone-fit, carrier-based (with heated gutta-percha), warm vertical compaction]. Using scanning electron microscopy, transversal root cross-sections were analyzed, and the maximum depth of RCS penetration was measured (396 sections, in total, corresponded to the apical, middle, and coronary third). Results. Group AH Plus™/warm vertical compaction yielded the highest penetration depth - 1,165 µm, followed by EndoREZ™/cone-fit - 1,154 µm; the lowest depth was measured for EndoREZ™/warm vertical compaction - 502 µm. The mean value of the maximum penetration depth of RCS yielded 1,204 µm in the coronary thirds, 1,005 µm in the middle thirds, and 770 µm in the apical thirds. The AH Plus™ RCS penetrated deeper into dentinal tubules when the obturation techniques with heated gutta-percha were applied, while the opposite findings were obtained for the EndoREZ ™ RCS. Conclusion. According to our research, the RCS penetration depth appears to be influenced by the RCS type used, as well as the obturation technique applied. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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84. Digital Pathology Update.
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Cudd, Sarah K., Schellhase, Chris W., Barkei, Erica K., Johnson, James E., and Kim, Robert K
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- *
MICROCOMPUTER workstations (Computers) , *TECHNOLOGICAL innovations , *PATHOLOGY , *PATHOLOGISTS - Abstract
The advent and maturation of whole slide imaging scanning technology brings another dimension to the practice of modern pathology. This new technology allows pathologists to view digitally scanned slides from any computer workstation, irrespective of distance, making consultation and education faster and easier. The purpose of this update is to educate personnel about this exciting new process and describe it's use in research, consultation, and diagnostics within the Army Veterinary Corps. Advantages and limitations are discussed, along with potential future applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
85. Crime Light Imaging (CLI): A Novel Sensor for Stand-Off Detection and Localization of Forensic Traces.
- Author
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Chiuri, Andrea, Chirico, Roberto, Angelini, Federico, Andreoli, Fabrizio, Menicucci, Ivano, Nuvoli, Marcello, Cano-Trujillo, Cristina, Montalvo, Gemma, and Lazic, Violeta
- Subjects
- *
CRIME scenes , *DETECTORS , *CRIME , *SEMEN , *LATENT variables - Abstract
Stand-off detection of latent traces avoids the scene alteration that might occur during close inspection by handheld forensic lights. Here, we describe a novel sensor, named Crime Light Imaging (CLI), designed to perform high-resolution photography of targets at a distance of 2–10 m and to visualize some common latent traces. CLI is based on four high-power illumination LEDs and one color CMOS camera with a motorized objective plus frontal filters; the LEDs and camera could be synchronized to obtain short-exposure images weakly dependent on the ambient light. The sensor is integrated into a motorized platform, providing the target scanning and necessary information for 3D scene reconstruction. The whole system is portable and equipped with a user-friendly interface. The preliminary tests of CLI on fingerprints at distance of 7 m showed an excellent image resolution and drastic contrast enhancement under green LED light. At the same distance, a small (1 µL) blood droplet on black tissue was captured by CLI under NIR LED, while a trace from 15 µL semen on white cotton became visible under UV LED illumination. These results represent the first demonstration of true stand-off photography of latent traces, thus opening the way for a completely new approach in crime scene forensic examination. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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86. A Bandwidth Scanning Game with a Sophisticated Adversary.
- Author
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Garnaev, Andrey and Trappe, Wade
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BANDWIDTHS ,ENTROPY ,GAMES - Abstract
Scanning a large bandwidth of radio spectrum for anomalous signals is a fundamental challenge that must be addressed in building a secure spectrum sharing system. When designing a bandwidth scanning algorithm, the system engineer faces a problem of which band to scan and how long to scan each band. Traditionally, in such a problem, the adversary is considered as one who wants to achieve a malicious goal, e.g., to sneak usage of a particular band while being undetected. In this paper, we deal with a new type of adversary, called a sophisticated adversary, who, besides the basic goal of being malicious and undetected, also has a secondary goal to achieve the basic goal in the most unpredictable way. As a metric for such unpredictability we consider the entropy associated with the adversary's strategy. The problem is modeled by a two-player game between an Intrusion Detection System (IDS) and the adversary. The equilibrium is found in closed form. Finally, weighting coefficients for the basic and secondary goals of the adversary are optimized via proportional fairness criteria. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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87. MicroED structure of lipid-embedded mammalian mitochondrial voltage-dependent anion channel
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Martynowycz, Michael W, Khan, Farha, Hattne, Johan, Abramson, Jeff, and Gonen, Tamir
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Underpinning research ,1.1 Normal biological development and functioning ,Animals ,Cryoelectron Microscopy ,Crystallization ,Lipids ,Mice ,Microscopy ,Electron ,Scanning ,Microscopy ,Electron ,Transmission ,Mitochondrial Proteins ,Protein Conformation ,Voltage-Dependent Anion Channels ,cryoEM ,MicroED ,bicelle crystallization ,FIB/SEM ,microcrystal electron diffraction - Abstract
A structure of the murine voltage-dependent anion channel (VDAC) was determined by microcrystal electron diffraction (MicroED). Microcrystals of an essential mutant of VDAC grew in a viscous bicelle suspension, making it unsuitable for conventional X-ray crystallography. Thin, plate-like crystals were identified using scanning-electron microscopy (SEM). Crystals were milled into thin lamellae using a focused-ion beam (FIB). MicroED data were collected from three crystal lamellae and merged for completeness. The refined structure revealed unmodeled densities between protein monomers, indicative of lipids that likely mediate contacts between the proteins in the crystal. This body of work demonstrates the effectiveness of milling membrane protein microcrystals grown in viscous media using a focused ion beam for subsequent structure determination by MicroED. This approach is well suited for samples that are intractable by X-ray crystallography. To our knowledge, the presented structure is a previously undescribed mutant of the membrane protein VDAC, crystallized in a lipid bicelle matrix and solved by MicroED.
- Published
- 2020
88. Simple methods to remove microbes from leaf surfaces
- Author
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Guzmán, J Paola Saldierna, Nguyen, Kennedy, and Hart, Stephen C
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Endophytes ,Microscopy ,Electron ,Scanning ,Pinus ,Plant Leaves ,Populus ,Sterilization ,endophyte ,leaf surface sterilization ,Pinus contorta ,Populus fremontii ,scanning electron microscopy ,Microbiology ,Medical Microbiology - Abstract
Endophytes have been defined as microorganisms living inside plant tissues without causing negative effects on their hosts. Endophytic microbes have been extensively studied for their plant growth-promoting traits. However, analyses of endophytes require complete removal of epiphytic microorganisms. We found that the established tests to evaluate surface sterility, polymerase chain reaction, and leaf imprints, are unreliable. Therefore, we used scanning electron microscopy (SEM) as an additional assessment of epiphyte removal. We used a diverse suite of sterilization protocols to remove epiphytic microorganisms from the leaves of a gymnosperm and an angiosperm tree to test the influence of leaf morphology on the efficacy of these methods. Additionally, leaf tissue damage was also evaluated by SEM, as damaging the leaves might have an impact on endophytes and could lead to inaccurate assessment of endophytic communities. Our study indicates, that complete removal of the leaf cuticle by the sterilization technique assures loss of epiphytic microbes, and that leaves of different tree species may require different sterilization protocols. Furthermore, our study demonstrates the importance of choosing the appropriate sterilization protocol to prevent erroneous interpretation of host-endophyte interactions. Moreover, it shows the utility of SEM for evaluating the effectiveness of surface sterilization methods and their impact on leaf tissue integrity.
- Published
- 2020
89. A comprehensive review on magnetic imaging techniques for biomedical applications
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Azamat Mukhatov, Tuan‐Anh Le, Tri T. Pham, and Ton Duc Do
- Subjects
Magnetic Imaging Techniques (MIT) ,Magnetic Particle Imaging (MPI) ,Magnetic Resonance Imaging (MRI) ,medicine ,scanning ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract This article presents a comprehensive review of current Magnetic Imaging Techniques (MIT), specifically Magnetic Particle Imaging (MPI) and Magnetic Resonance Imaging (MRI) methods as well as their impacts and potential in biomedical applications. The paper particularly focuses on several perspectives of MPI and MRI techniques including technical considerations, advantages, limitations, applications, future trends. Surprisingly, there are not many review articles that focused on MPI and MRI. This review will give a complete overview of present technology, perspectives, and potential future developments for MPI and MRI. MIT has become an essential and integral part of medical diagnosis in many large medical clinics and hospitals. This area is rapidly developing and evolving to meet the huge demands in medical diagnosis and prevention. MPI and MRI are promising technologies that provide reliable and effective diagnosis for many diseases including cancer. MIT uses non‐invasive scanning to obtain a detailed image of the body's tissues or organs without the necessity for surgery. These techniques allow us to detect symptoms of serious diseases at an early stage. Early detection also gives patients the chance to get the right care before their illnesses advance to a late, incurable stage, potentially saving many lives.
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- 2023
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90. Anticipating and Addressing Unconventional Future Crimes: A Mechanistic Analysis in the Context of Technological Advancements.
- Author
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Hafez, Adel Ibrahim
- Subjects
TECHNOLOGICAL innovations ,CRIME analysis ,NATIONAL security ,CYBERTERRORISM ,ESPIONAGE - Abstract
Copyright of Police Thought is the property of Sharjah Police Research Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
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91. Effect of Pistacia lentiscus Extract on Dentin Remineralization: An In Vitro Study
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A Valian, A Tareh, M Zarei, and S Gholami Mandali
- Subjects
dentin sensitivity ,dentin desensitizing agents ,pistacia lentiscus ,microscopy ,electron ,scanning ,Dentistry ,RK1-715 - Abstract
Background and Aim: This study aimed to assess the efficacy of Pistacia lentiscus (P. lentiscus) extract for dentin remineralization. Materials and Methods: This in vitro experimental study evaluated 45 extracted sound human premolars; pH cycling was performed to assess the effect of 10% P. lentiscus extract on dentin remineralization. The samples were randomly assigned to three groups of 1000 ppm sodium fluoride (NaF) solution, 10% P. lentiscus extract, and deionized water. To induce dentinal lesions, the teeth were immersed in a demineralizing solution at 37°C for 96 hours. The demineralized samples were then subjected to pH cycling for 14 days, and then underwent the Vickers microhardness test and scanning electron microscopic (SEM) assessment. Data were analyzed by repeated-measures ANOVA. Results: The mean microhardness in the NaF group was significantly higher than that in the extract and control groups after 14 days (P
- Published
- 2023
92. On the detection of vulnerable plaques in human coronary atherosclerosis
- Author
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Moss, Alastair James, Newby, David, and Dweck, Marc
- Subjects
616.1 ,coronary artery disease ,scanning ,CT scan ,18F-sodium fluoride - Abstract
BACKGROUND: Coronary atherosclerosis is a chronic inflammatory disease which progresses to luminal stenosis and plaque rupture events. Recent developments in non-invasive cardiovascular imaging have enabled the identification of coronary plaques with an increased propensity to rupture. Coronary computed tomography angiography allows visualisation of thearterial wall to discern regions of high-risk plaque in patients with non-obstructive and obstructive coronary artery disease. The anatomical assessment afforded by coronary computed tomography angiography can be combined with hybrid positron emission tomography computed tomography to provide a measure of disease activity. Using novel radiotracers targeted at specific cellular pathways in atherosclerosis, it is now possible to observe plaque activitywith 18F-sodium fluoride in vivo. The principal aims of this thesis were to evaluate the prognostic impact of adverse plaque features using standard coronary computed tomography angiography,to perform reproducibility and histological validation studies ofa novel non-invasive imaging technique for detecting high-risk plaquewith coronary 18F-fluoride imagingand assess whether coronary 18F-fluoride could be used to select high-risk individuals as part a phase 3 clinical trial of an investigational medicinal product. ADVERSE CORONARY ARTERY PLAQUE CHARACTERISTICS IN PATIENTS WITH CORONARY ARTERY DISEASE: In a prognostic substudy of the SCOT-HEART trial, adverse plaque features were associated with a three-fold increase in coronary heart disease death or non-fatal myocardial infarction (hazard ratio 3.01 (95% confidence intervals 1.61 to 5.63); p=0.001). Patients with both obstructive disease and adverse plaque had the highest event rate with a greater than 10-fold increase in events (hazard ratio 11.50 (95% confidence interval 3.39 to 39.04); p < 0.001). However, these associations weredependent coronary artery calcium score, a surrogate measureof coronary plaque burden. MOLECULAR CORONARY PLAQUE IMAGING USING 18F-FLUORIDE: To explore whether a novel non-invasive imaging technique could accurately detect regions of coronary microcalcification in patients with coronary artery disease, a scan-rescan reproducibility study of 30 patients was undertaken. Using a standardised metric (coronary to atrial blood pool ratio, TBRMAX), 18F-fluoride activity couldbe precisely and reproducibly measured within the coronary vasculature. The analytical performance of coronary 18F-fluoride activity was sufficient to determine whether this radiotracer couldbe used as a non-invasive imaging marker of plaque vulnerability in clinical trials. EX VIVO 18F-FLUORIDE UPTAKE IN HUMAN CORONARY ATHEROSCLEROSIS: Ex vivovalidation of coronary artery specimens using 18F-fluoride demonstrated highly selectivity for hydroxyapatite deposition in atherosclerotic coronary plaque. Specifically, coronary 18F-fluoride binding has a high signal to noise ratio compared with surrounding myocardium that makes it feasible to identify coronary mineralisation activity. Areas of 18F-fluoride binding are associated with osteopontin, an inflammatory-stimulated glycophosphoproteinthat increases tissue mineralisation. These results suggest that 18F-fluoride is a non-invasive imaging biomarker of active coronary atherosclerotic mineralisation. TICAGRELOR TO REDUCE MYOCARDIAL INJURY IN PATIENTS WITH HIGH-RISK CORONARY ARTERY PLAQUE: In a double-blind randomised placebo-controlled trial, 191 patients with multivessel coronary artery disease underwent 18F-fluoride positron emission tomography and computed tomography coronary angiography. In patients with high-risk plaque defined by 18F-fluoride uptake in at least one coronary plaque (n=120/191), there was no evidence thatdual antiplatelet therapy with ticagrelor affected 30-day plasma troponin concentrations (ratio of geometric means1.11 [95% confidence interval 0.90-1.36], p=0.32). CONCLUSIONThese observations suggest that high-risk plaque detection identifies individuals at increased risk of cardiovascular events. Coronary 18F-fluoride can be utilised in the setting of randomised controlled trials as a precise biomarker of plaque activity. Further projects to assess whether coronary 18F-fluoride can predict plaque rupture events are ongoing.
- Published
- 2020
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93. Hardware, software and organizational means of protecting the resources of the personal data information system from unauthorized access by means of 'sniffing attacks'
- Author
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A. R. Gazizov
- Subjects
security analysis ,active traffic interception ,resource security ,anchoring in the system ,information system ,passive traffic interception ,personal data ,access ,information collection ,sniffing attack ,scanning ,resource protection tools ,report generation ,analysis stages ,Technology - Abstract
Objective. The article discusses hardware and software methods of protecting the resources of the personal data information system from unauthorized access by means of "sniffing attacks"; the essence of which is to intercept data that is delivered within the observed system in the form of packets.Method. The analysis of the security of resources by the personal data information system regarding unauthorized access to data by means of "sniffing attacks" includes five conditional stages: collecting information in the personal data information system, scanning the personal data information system, gaining access to the personal data information system, securing personal data in the information system, generating a report; at the same time, security analysis it is always associated with unauthorized access to data.Result. To prevent unauthorized access to data by means of "sniffing attacks", the following software and hardware solutions are proposed to minimize the consequences of unauthorized exposure to the personal data information system: the use of the HTTPS protocol, a secure version of the HTTP protocol; the use of a static ARP table generated manually; scanning of the computer network of the personal data information system by the AntiSniff program; encryption of the computer network traffic networks of the personal data information system.Conclusion.The presented hardware and software solutions allow minimizing the consequences of unauthorized impact on personal data information systems.
- Published
- 2022
- Full Text
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94. INVESTIGATING THE NETWORK TRAFFIC USING THE COMMAND-LINE PACKETS SNIFFER TCPDUMP IN KALI LINUX.
- Author
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Boyanov, Petar Kr.
- Subjects
- *
COMPUTER network traffic - Abstract
In this scientific article a comprehensive investigation of the network traffic using the command-line packets sniffer Tcpdump in kali Linux is made. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
95. BASIC NETWORK PENETRATION TESTING WITH THE NETWORK TOOL NETCAT IN LINUX-BASED OPERATING SYSTEMS.
- Author
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Boyanov, Petar Kr.
- Abstract
In this scientific article a basic network penetration testing with the network tool Netcat in Linux-based operating systems is presented. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
96. Improving the Mechanical Properties of Orthodontic Occlusal Splints Using Nanoparticles: Silver and Zinc Oxide.
- Author
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Barbur, Ioan, Opris, Horia, Colosi, Horatiu Alexandru, Baciut, Mihaela, Opris, Daiana, Cuc, Stanca, Petean, Ioan, Moldovan, Marioara, Dinu, Cristian Mihail, and Baciut, Grigore
- Subjects
ZINC oxide ,SILVER nanoparticles ,SILVER oxide ,POLYMETHYLMETHACRYLATE ,SCANNING electron microscopy - Abstract
The goal of the current study was to determine the mechanical proprieties of polymethylmethacrylate (PMMA) and the improved compound, the graphene-based PMMA, with Zn and Ag and to compare the results. Scanning electron microscopy analysis of the samples before and after the mechanical test was conducted. The compression behavior, flexural properties, tensile strength, and shape of the samples were all investigated and compared between the variants of PMMA. Commercially available polymethylmethacrylate was used (Orthocryl
® —Dentaurum, Ispringen, Germany) with the salt and pepper technique according to the manufacturer's instructions to produce 20 samples for each mechanical trial with standard cylinders (4 mm diameter × 8 mm length) for compression, parallelepipedal prisms for flexing (2 mm × 2 mm × 25 mm) and flat samples for traction. There was no statistical difference in the mechanical proprieties of the samples evaluated, although there were values that could suggest significance. The graphene-based PMMA demonstrated good mechanical proprieties, like the commercially available PMMA, and appears promising for future clinical use based on its multiple advantages. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
97. Multi-modal access method (eye-tracking + switch-scanning) for individuals with severe motor impairment: A preliminary investigation.
- Author
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Fager, S. K., Sorenson, T., Jakobs, E., Koester, H., Jakobs, T., and Beukelman, D. R.
- Abstract
Individuals with severe motor impairments often require alternative means to access computers and communication technology. A range of alternative access devices exist; however, most rely on use of a single access modality. While this approach works for some individuals, it can be limiting for others. This study explored the use of a multi-modal prototype (eye-tracking + switch-scanning) on typing performance with a range of individuals with motor impairments. The multi-modal prototype was compared to eye-tracking alone for this study. Results indicated that the multi-modal prototype had significantly slower typing rate but significantly lower total errors compared to eye-tracking alone. Analysis of individual data revealed four subgroups of clinical relevance including individuals that 1) benefit from multi-modal, 2) benefit from eye-tracking, 3) demonstrate learning and 4) demonstrate fluctuating performance. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
98. Bifocal Dual Reflectarray with Curved Main Surface.
- Author
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Pino, Antonio, Rodriguez-Vaqueiro, Yolanda, Martinez-de-Rioja, Eduardo, Martinez-de-Rioja, Daniel, González-Valdés, Borja, Arias, Marcos, Rubiños, Oscar, Encinar, José Antonio, and Toso, Giovanni
- Subjects
CURVED surfaces ,ANTENNAS (Electronics) ,GEOMETRICAL optics ,RAY tracing ,SAMPLING (Process) ,TELECOMMUNICATION satellites - Abstract
This paper presents a novel approach to synthesizing curved reflectarrays using Geometrical Optics (GO). It introduces the concepts of virtual normal and path length shift, which enable a vector-based formulation of the problem that can be solved using ray tracing techniques. The formulation is applied for the design of two different versions of a Dual Bifocal Reflectarray with a parabolic main surface and a flat subreflectarray. The first version aims to enhance the performance of the multibeam antenna by providing a focal ring located at the feed cluster plane. The second version focuses on improving the scanning characteristics of the antenna in the horizontal plane by incorporating two foci. The synthesis procedure yields samples of the path length shift or its derivatives. To reconstruct the phase distribution, an interpolation scheme is employed and described in this paper. Numerical results are presented for both the focal-ring and two-foci configurations, demonstrating the feasibility of this solution for multibeam or scanning satellite antennas operating in the Ka. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
99. Arrhythmogenicity of anti-tachycardia pacing in patients with implantable cardioverter defibrillator.
- Author
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Awad, Sherien Samy, Azeez, Emmanuel Fares, Taha, Mohamed Ossama, El-Naggar, Wael Mohamed, and El-Damaty, Ahmed
- Abstract
Background: Anti-tachycardia pacing therapy (ATP) has shown comparable efficacy to shock therapy in ventricular tachycardia (VT) termination with better quality of life. However, some ATPs may lead to VT acceleration or degeneration to ventricular fibrillation (VF), which will result in more ICD shocks. The aim of this study was to investigate the predictors of VT acceleration by ATP therapy in a real-life patient cohort. Results: We retrospectively reviewed 448 monomorphic VT episodes that required ATP therapy in 60 patients with structural heart diseases implanted with ICD or CRTD. The clinical data of the patients and the episodes' details were evaluated. We found that patients with a higher ejection fraction (EF) were more likely to be cardioverted by ATP therapy (P: 0.024). VT acceleration was more frequent in patients with lower EF (mean 31.24 ± 4.08) compared with the non-accelerated patients with higher EF (mean 37.00 ± 9.4, P: 0.016). The percentage of accelerated episodes was 8.5%. VT episodes with a mean cycle length (CL) < 310 ms are more likely to accelerate (sensitivity 76.3%, specificity 67.7%, PPV value 45%, NPV 86%, and AUC 0.790). There was a statistically significant difference in the accelerated VT episodes as compared to non-accelerated episodes regarding the number of ATP bursts (mean 3.66 ± 2.22 vs. 1.76 ± 1.35, P: < 0.001), ramp (23.7% vs. 4.2%, P: < 0.001), scanning (55.3% vs. 31.3%, P: 0.003) and burst adaptive cycle length (mean 83.55 ± 2.92 vs. 84.64 ± 2.61, P: 0.016). In a multivariate analysis, the VT CL, number of ATP bursts and ramp pacing predicted VT acceleration by ATP therapy. Conclusions: Ventricular tachycardia in patients with low LV EF and fast VTs with a CL less than 310 ms were more likely to accelerate with ATP therapy. The number of ATP bursts and the use of ramp had a significant effect on VT acceleration. To avoid VT acceleration by ATP therapy, ramp pacing better be avoided, especially in fast VTs, and lesser number of bursts should be delivered. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
100. Regenerative and Protective Effects on Dental Tissues of a Fluoride–Silicon-Rich Toothpaste Associated with a Calcium Booster: An In Vitro Study.
- Author
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Vilhena, Fabiano Vieira, Grecco, Simone dos Santos, González, Alejandra Hortencia Miranda, and D'Alpino, Paulo Henrique Perlatti
- Subjects
DENTINAL tubules ,TOOTHPASTE ,CALCIUM ,REGENERATION (Biology) ,X-ray spectroscopy - Abstract
Calcium boosters have been used as a supplement for fluoride toothpastes to repair the dental tissues and reduce dentin permeability. This in vitro study aimed to characterize the regenerative and protective effects of the treatment of dental tissues with a fluoride–silicon-rich toothpaste associated with a calcium booster. Bovine enamel and dentin blocks (n = 5) were obtained (4 × 4 × 6 mm). A fluoride–silicon-rich toothpaste and a calcium booster were used to brush the enamel and dentin both immediately and five days afterwards. The outcomes were then compared to those of the untreated control group. After that, the specimens were cross-sectioned. SEM was used to evaluate the micromorphology of the surface and cross-section. Energy-dispersive X-ray spectroscopy (EDS) was used to determine the elemental analyses (weight%). After treatment for 5 days with a booster/silicon-rich toothpaste, EDS analysis demonstrated that it induced a significant mineral change. It was also able to form a protective silicon-enriched mineral layer on both enamel and dentin surfaces. It was demonstrated in vitro that a fluoride–silicon-rich toothpaste associated with a calcium booster regenerates the dental tissues, remineralizing the enamel structure and occluding the dentin tubules. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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