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Background: Conventional imaging is the backbone of dentistry. Intraoral and extraoral radiographs are commonly used for diagnosis and clinical management for multiple maxillofacial pathologies. However, they are of a two-dimensional nature and have numerous limitations and disadvantages. Cone beam computed tomography (CBCT) adds a third dimension to the two-dimensional image. The multiple pathological conditions that remain undetected in two-dimensional imaging can be easily diagnosed with CBCT and, to a large extent, help with treatment planning and prognosis. Aim: To compare intraoral and extraoral two-dimensional imaging to CBCT to prove the importance of CBCT in diagnosis and treatment planning. Setting and Design: Different cases in which patients underwent two-dimensional intraoral / extraoral imaging and CBCT were reported and variations in radiographic diagnosis were compared. Conclusion: CBCT is a boon to dentistry. The third dimension adds invaluable information that modifies the diagnosis and treatment plan and hence helps improve the prognosis.

In this paper, we report a novel aluminum nitride (AlN) resonant micro-electromechanical systems (MEMS) accelerometer. The spring beams are T-shaped with two masses hanged at the end. This accelerometer is sensitive to the $z$ -axis acceleration due to a thin thickness. Different from the working mechanism of the ordinary MEMS resonant accelerometers, masses of this accelerometer are excited to resonate in-plane. In addition the stiffness of spring beams changes significantly when an out plane ($z$ -axis) inertial force applied on the structure. Therefore, the resonant frequency of the structure will change with the out-plane inertial force. The resonant properties and sensitivities of this AlN accelerometer are simulated by COMSOL Multiphysics. The accelerometer is fabricated and tested. The size of the whole structure is $464\times 650\,\,\mu \text{m}^{2}$. The resonant frequency is 16.10925 kHz at the static state. The sensing-axis sensitivity of this accelerometer is 1.11 Hz/g (i.e., 68.9 ppm/g) tested from −5g to +5g. The linearity of the accelerometer is 0.9954. The cross-axis sensitivities are 0.053 Hz/g ($x$ -axis) and 0.048 Hz/g ($y$ -axis) respectively. The temperature coefficient of frequency (TCF) of this accelerometer is 0.815 Hz/ °C (i.e., 50.6 ppm/°C), tested from 0 °C to 50 °C. [2019-0062] [ABSTRACT FROM AUTHOR]

In this paper, we report a novel aluminum nitride (AlN) thin-film piezoelectric resonant accelerometer. Different from the ordinary MEMS (micro-electro-mechanical systems) resonant accelerometers, the entire structure of the accelerometer, including the mass and the springs, is excited to resonate in-plane, and the resonance frequency is sensitive to the out-plane acceleration. The structure is centrosymmetrical with serpentine electrodes laid on supporting beams for driving and sensing. The stiffness of the supporting beams changes when an out-plane inertial force is applied on the structure. Therefore, the resonance frequency of the accelerometer will also change under the inertial force. The working principle is analyzed and the properties are simulated in the paper. The proposed AlN accelerometer is fabricated by the MEMS technology, and the structure is released by an ICP isotropic etching. The resonance frequency is 24.66 kHz at a static state. The quality factor is 1868. The relative sensitivity of this accelerometer, defined as the shift in the resonance frequency per gravity unit (1 g = 9.8 m/s2) is 346 ppm/g. The linearity of the accelerometer is 0.9988. The temperature coefficient of frequency (TCF) of this accelerometer is −2.628 Hz/°C (i.e., −106 ppm/°C), tested from −40 °C to 85 °C.

Purpose: The purpose of this study was to determine if CT for appendicitis can be abbreviated to begin at the top of the L2 vertebral body level and still maintain the detection rate of appendicitis and other symptomatic pathology without omitting significant incidental findings.Methods: Retrospective review of CT abdomen-pelvis exams for suspected appendicitis over a 5-month period was performed. The Z-axis scan length of the original full scans and theoretical limited scans from the top of L2 were recorded and calculated. Images were reviewed for incidental findings above the L2 vertebral body level and categorized by severity per American College of Radiology (ACR) white paper guidelines. Final diagnoses based on imaging findings were also recorded.Results: One hundred nineteen patients (46 males, 73 females, mean age 29 ± 14) were included. Appendicitis was present in 26 cases (22%). Using a theoretical scan beginning at the top of the L2 vertebral body, none of the findings leading to diagnosis of appendicitis would have been missed. A total of 30 incidental findings were found above the L2 vertebral body. Per ACR white paper guidelines, 26 of these findings did not require additional imaging follow-up. Additional follow-up imaging was recommended for 3 of the findings above L2, and 1 right adrenal metastasis was found above L2 in a patient with previously undiagnosed NSCLC. This patient coincidentally also had appendicitis. No symptomatic pathology would have been missed had the scans begun at the top of the L2 vertebral body. Such an abbreviated scan would have resulted in a mean Z-axis reduction of 12.9 cm (30.3%).Conclusions: CT using abbreviated Z-axis scan length can reduce radiation dose and provide necessary imaging needed to diagnose appendicitis or other symptomatic pathology without omitting significant incidental findings. [ABSTRACT FROM AUTHOR]

The purpose of this work is to calibrate a not expensive microscope to be applied in Optical Disector estimation. The evaluation of "Z-axis" bias and the "Z-axis" calibration were made utilizing a cover slip and a "manual digimatic outside micrometer scale" (Mitutoyo, Japan). Calibrating the cover slip we performed the calibration of the "Z-axis" of a microscope. In the cover slip two lines were painted with different colors using a pen glass. A blue line was painted on the up surface and another line (red) on the bottom surface of the cover slip forming a cross. Two metal rings with one palette welded in each were adapted in the microscope. Other palette was welded in the gross focuses in order to restrict the route of the fine focuses (Z-axis study) using the two palettes fixed in both rings. Results show that 10 micrometers in "Z-axis" were equal to 3.2 micrometers in the scale of its fine focuses of the microscope. Then, a Disector of 10μm (10μm in Z-axis) is equal to 3.2 micrometers in the fine focuses of this microscope. In conclusion, "Z-axis" calibration is crucial to assure enough precision for Disector Method since the equipment can be manufactured without the ideal precision or its precision can be lost after use.O propósito deste trabalho é a Calibração de um microscópio comum de baixo custo de forma a usá-lo para estimativas do Método Disector Óptico. A avaliação do viés e a calibração do "eixo-Z" foram feitas usando uma lamínula e um "micrômetro manual digital" (Mitutoyo, Japan). Com a cali-bração da lamínula, calibramos o "eixo-Z" de um microscópio. Foram pintadas duas linhas com diferentes cores utilizando canetas para vidro. Uma linha (azul) foi pintada na superfície superior da lamínula e outra linha (vermelha) foi pintada na superfície inferior da lamínula, formando uma cruz. Dois anéis de metal com uma paleta de metal soldada a cada um deles foram adaptados ao micrométrico do microscópio. Outra paleta foi soldada ao macrométrico do mesmo microscópio, o que foi feito de forma a limitar o percurso do micrométrico (eixo-Z) pela ação desta em conjunto com a ação das duas paletas fixadas no micrométrico. Os resultados mostraram que 10 micrômetros no "eixo-Z" do microscópio foi igual a 3,2 na escala do seu micrométrico. Assim, um Disector de 10μm (10μm no eixo-Z) é igual a 3,2 micrômetros no micrométrico do microscópio utilizado. Concluindo, a calibração do eixo-Z é crucial para assegurar a precisão suficiente para as avaliações usando o Método Disector, já que os equipamentos podem ser manufaturados sem a precisão ideal ou podem perder sua precisão durante o tempo com o uso.

Background: The use of virtual microscopy (VM) in clinical cytology has been limited due to the inability to focus through three dimensional (3D) cell clusters with a single focal plane (2D images). Limited information exists regarding the optimal scanning parameters for 3D scanning. Aims: The purpose of this study was to determine the optimal number of the focal plane levels and the optimal scanning interval to digitize gynecological (GYN) specimens prepared on SurePath™ glass slides while maintaining a manageable file size. Subjects and Methods: The iScanCoreo Au scanner (Ventana, AZ, USA) was used to digitize 192 SurePath™ glass slides at three focal plane levels at 1 ì interval. The digitized virtual images (VI) were annotated using BioImagene's Image Viewer. Five participants interpreted the VI and recorded the focal plane level at which they felt confident and later interpreted the corresponding glass slide specimens using light microscopy (LM). The participants completed a survey about their experiences. Inter™rater agreement and concordance between the VI and the glass slide specimens were evaluated. Results: This study determined an overall high intra™rater diagnostic concordance between glass and VI (89™97%), however, the inter™rater agreement for all cases was higher for LM (94%) compared with VM (82%). Survey results indicate participants found low grade dysplasia and koilocytes easy to diagnose using three focal plane levels, the image enhancement tool was useful and focusing through the cells helped with interpretation; however, the participants found VI with hyperchromatic crowded groups challenging to interpret. Participants reported they prefer using LM over VM. This study supports using three focal plane levels and 1 Background: The use of virtual microscopy (VM) in clinical cytology has been limited due to the inability to focus through three dimensional (3D) cell clusters with a single focal plane (2D images). Limited information exists regarding the optimal scanning parameters for 3D scanning. Aims: The purpose of this study was to determine the optimal number of the focal plane levels and the optimal scanning interval to digitize gynecological (GYN) specimens prepared on SurePath™ glass slides while maintaining a manageable file size. Subjects and Methods: The iScanCoreo Au scanner (Ventana, AZ, USA) was used to digitize 192 SurePath™ glass slides at three focal plane levels at 1 ì interval. The digitized virtual images (VI) were annotated using BioImagene's Image Viewer. Five participants interpreted the VI and recorded the focal plane level at which they felt confident and later interpreted the corresponding glass slide specimens using light microscopy (LM). The participants completed a survey about their experiences. Inter™rater agreement and concordance between the VI and the glass slide specimens were evaluated. Results: This study determined an overall high intra™rater diagnostic concordance between glass and VI (89™97%), however, the inter™rater agreement for all cases was higher for LM (94%) compared with VM (82%). Survey results indicate participants found low grade dysplasia and koilocytes easy to diagnose using three focal plane levels, the image enhancement tool was useful and focusing through the cells helped with interpretation; however, the participants found VI with hyperchromatic crowded groups challenging to interpret. Participants reported they prefer using LM over VM. This study supports using three focal plane levels and 1 ì interval to expand the use of VM in GYN cytology. Conclusion: Future improvements in technology and appropriate training should make this format a more preferable and practical option in clinical cytology. ì interval to expand the use of VM in GYN cytology. Conclusion: Future improvements in technology and appropriate training should make this format a more preferable and practical option in clinical cytology. [ABSTRACT FROM AUTHOR]

K. Yamashiro, M. Tagami, K. Azuma, A. Nakamura, O. Kato, K. Taira, M. Azuma, H. Takeda and H. Suzuki This study examined whether cytological diagnosis through the use of a video, which shows the changing depth of focus in the microscopic field, described as a z-axis video, is useful compared with a still image. From 17 cytology preparations of fine needle aspiration of the breast, we made six z-axis videos per case. A frame exhibiting the characteristic features was then extracted from each video and saved as a representative still image. One hundred and twenty-eight volunteer cytotechnologists were randomly divided into two groups of video observers and still image observers. The participants were asked to make a diagnosis of benign, indeterminate, suspicious or malignant without having any clinical information other than the age of the patient. Diagnoses were categorized as 'recommended' or 'unacceptable' according to degree of correlation with histology. The number of definitive diagnoses of 'benign' or 'malignant' were increased in video observers, and indeterminate or suspicious categories were decreased ( P = 0.013). The distribution of diagnostic categories in three of the 17 cases was significantly different; the distribution in the remaining cases was similar between the two groups. The z-axis video observers may have selected the definite diagnoses with confidence because they observed valuable microscopic findings by 'focusing through observation'. The average number of 'recommended' diagnoses by individual observers was significantly higher in the video observer group than in the still image observer group ( P = 0.016). In contrast, the average number of 'unacceptable' diagnoses was significantly lower ( P = 0.019). A z-axis video is easy to obtain and is therefore expected to become a powerful diagnostic modality for the external quality assessment of clinical cytology and even in the field of primary cytodiagnosis. [ABSTRACT FROM AUTHOR]

This article argues that while a semiotic analysis of composition in the screen, page and image has significant heuristic value, this would be further enhanced were it also to take into account surface and depth. It is argued that these two aspects of composition are critical for successful reading/viewing of images, and especially for digital images and their navigation. Semantic primitives, or primes, for space (where/place; here; above; below; far; near; side; inside) are employed in this argument for the development of a more comprehensive analysis of spatial integration for the screen, page and image. [ABSTRACT FROM AUTHOR]

Manufacturing high value-added parts often requires a considerable amount of time spent on machining, during which the machine’s dimensional characteristics may change. During this study, we endeavoured to characterise the dimensional change of the slideways and ball screw spindle of the Z-axis on an NC lathe. Indeed, such changes are harmful when it comes to obtaining precise dimensions along the Z direction of the lathe. Firstly, we specified the context in which the study was to be conducted and the problem we were confronted with. We then conducted an experimental study to highlight the parameters having an influence on the dimensional changes of the Z-axis. We then implemented modelling to generate a prediction model for this axis’s behaviour during machining. We were thus able to compensate for such errors by inserting programmed offsets, calculated from the prediction model [1]. We rounded off our study by milling a series of parts using a corrected NC programme that included a compensation for the dimensional change of the Z-axis in order to validate our approach. [ABSTRACT FROM AUTHOR]

Purpose: Various approaches in noise power spectrum (NPS) analysis are currently used for measuring a patient's longitudinal (z-direction) NPS from three-dimensional (3D) CT volume data. The purpose of this study was to clarify the relationship between those NPSs and 3D-NPS based on the central slice theorem., Methods: We defined the 3D-NPS(f x , f y , f z ) that was calculated by 3D Fourier transform (FT) from 3D noise data (3D-Noise(x, y, z), x-y scan plane). Here, f x , f y and f z are spatial frequencies corresponding to the axes of x, y and z, respectively. Based on the central slice theorem, we described three relationships as follows. (1) The f z -directional NPS calculated from the 3D-Noise(x=0, y=0, z) is equal to the profile obtained by projecting 3D-NPS(f x , f y , f z ) in f x - and f y -directions. (2) The f z -directional NPS calculated from the profile obtained by projecting 3D-Noise(x=0, y, z) in the y-direction is equal to the profile at f y =0 in the data obtained by projecting 3D-NPS(f x , f y , f z ) in the f x -direction. (3) The f z -directional NPS calculated from the profile obtained by projecting 3D-Noise(x, y, z) in x and y-directions is equal to the profile of 3D-NPS(f x =0, f y =0, f z ). To verify them, we compared the NPSs measured from actual 3D noise data that were obtained using a cylindrical water phantom., Results: In each relationship (1)-(3), the f z -directional NPS matched the profile obtained from the 3D-NPS(f x , f y , f z )., Conclusion: Based on the central slice theorem, we clarified the relationships between f z -directional NPSs and 3D-NPS. We should understand them and then consider which method should be used for f z -directional NPS measurement.

Background: The use of virtual microscopy (VM) in clinical cytology has been limited due to the inability to focus through three dimensional (3D) cell clusters with a single focal plane (2D images). Limited information exists regarding the optimal scanning parameters for 3D scanning. Aims: The purpose of this study was to determine the optimal number of the focal plane levels and the optimal scanning interval to digitize gynecological (GYN) specimens prepared on SurePath™ glass slides while maintaining a manageable file size. Subjects and Methods: The iScanCoreo Au scanner (Ventana, AZ, USA) was used to digitize 192 SurePath™ glass slides at three focal plane levels at 1 μ interval. The digitized virtual images (VI) were annotated using BioImagene′s Image Viewer. Five participants interpreted the VI and recorded the focal plane level at which they felt confident and later interpreted the corresponding glass slide specimens using light microscopy (LM). The participants completed a survey about their experiences. Inter-rater agreement and concordance between the VI and the glass slide specimens were evaluated. Results: This study determined an overall high intra-rater diagnostic concordance between glass and VI (89-97%), however, the inter-rater agreement for all cases was higher for LM (94%) compared with VM (82%). Survey results indicate participants found low grade dysplasia and koilocytes easy to diagnose using three focal plane levels, the image enhancement tool was useful and focusing through the cells helped with interpretation; however, the participants found VI with hyperchromatic crowded groups challenging to interpret. Participants reported they prefer using LM over VM. This study supports using three focal plane levels and 1 μ interval to expand the use of VM in GYN cytology. Conclusion: Future improvements in technology and appropriate training should make this format a more preferable and practical option in clinical cytology.

In this paper, we report a novel aluminum nitride (AlN) thin-film piezoelectric resonant accelerometer. Different from the ordinary MEMS (micro-electro-mechanical systems) resonant accelerometers, the entire structure of the accelerometer, including the mass and the springs, is excited to resonate in-plane, and the resonance frequency is sensitive to the out-plane acceleration. The structure is centrosymmetrical with serpentine electrodes laid on supporting beams for driving and sensing. The stiffness of the supporting beams changes when an out-plane inertial force is applied on the structure. Therefore, the resonance frequency of the accelerometer will also change under the inertial force. The working principle is analyzed and the properties are simulated in the paper. The proposed AlN accelerometer is fabricated by the MEMS technology, and the structure is released by an ICP isotropic etching. The resonance frequency is 24.66 kHz at a static state. The quality factor is 1868. The relative sensitivity of this accelerometer, defined as the shift in the resonance frequency per gravity unit (1 g = 9.8 m/s2) is 346 ppm/g. The linearity of the accelerometer is 0.9988. The temperature coefficient of frequency (TCF) of this accelerometer is −2.628 Hz/°C (i.e., −106 ppm/°C), tested from −40 °C to 85 °C. [ABSTRACT FROM AUTHOR]