Search

We describe the detection of cell nuclei in oral cytology using artificial intelligence (AI). We focused on the detection of cell nuclei because the ratio of cell nuclei to cytoplasm increases with increasing cell malignancy. As an initial step in the development of AI-assisted cytology, we investigated two methods for the automatic detection of cell nuclei in blue-stained cells in cytopreparation images. We evaluated the usefulness of the sliding window method (SWM) and the mask region-based convolutional neural network (Mask-RCNN) method in identifying cell nuclei in oral cytopreparation images. Thirty cases of liquid-based oral cytology were analyzed. First, we performed the SWM by dividing each image into 96 × 96 pixels. Overall, 591 images with or without blue-stained cell nuclei were prepared as the training data and 197 as the test data (from among 1576 images in total). Next, we performed the Mask-RCNN method by preparing 130 images of Class II and III lesions and creating mask images showing cell regions based on these images. By the SWM method, the highest detection rate for blue-stained cells in the evaluation group was found to be 0.9314. For Mask-RCNN, 37 cell nuclei were identified, and 1 cell nucleus was identified as a non-nucleus after 40 epochs (error rate: 0.027). Mask-RCNN was shown to be more accurate than SWM in identifying the cell nuclei. If the bluestained cell nuclei can be correctly identified automatically, the entire cell morphology can be grasped faster, and the diagnostic performance of cytology can be improved., Sensors and Materials, 35(2), pp.399-409; 2023

Fine-needle aspiration cytology (FNAC) is a specific and important test used for the diagnosis of thyroid gland cancer. We developed a thyroid gland phantom using original manufacturing techniques and direct three-dimensional (3D) printing. The aim of this study was to confirm the effectiveness of this phantom by collecting data to evaluate puncture training.Data from 45 ultrasonography-guided thyroid nodule FNAC procedures performed on our thyroid phantom were evaluated in our department. The first group comprised qualified physicians who specialized in thyroid gland treatment (group A; n = 10). The second and third groups comprised senior and junior residents (group B; n = 8 and group C; n = 12; respectively). The fourth group comprised students (group D; n = 15). We measured the times taken by these groups to complete each task.The skills of all participants in groups B, C, and D improved after using this phantom involving the major (parallel)- (0.47 ± 0.07) and short (orthogonal)-axes (0.52 ± 0.07) methods (P 0.001). The number of erroneous punctures decreased from 53 to 3.Our original phantom improved the puncture skills of students and junior doctors and was suitable as a tailored training model for practicing thyroid gland transfixion.

The radical copolymerization on α-substituted fluoroalkyl acrylate (FA) monomer bearing C4, C6, and C8 as perfluoroalkyl (Rf) groups, as well as the variation of α-substituents, hydrogen, methyl, and chlorine with styrene was investigated. Q-e values and monomer reactivity ratio of FA monomers were estimated. When the alpha position of FA monomer of C6 as Rf group was changed from −H to −CH3, the e value decreased from 0.85 to 0.60. The substituent of −Cl resulted in an e value of 1.06. The Q values were also markedly changed. When the alpha position was changed from −H to −CH3, the Q value increased from 0.38 to 0.79. The substituent of −Cl resulted in a Q value of 2.90. The copolymer composition of α-substituted FA monomers with stearyl acrylate (C18A) was simulated. The obtained results revealed that a chlorine substituent at the alpha position emphasizes the polymerization which would contribute to a novel material design containing a fluorine side chain in a monomer structure.

Endoscopic submucosa dissection (ESD) procedures, used to remove cancerous tissue from thin-walled organs such as the duodenum, often result in compromising the organ’s functionality, resulting in problematic leakage. While a device has been developed to enable the adherence of a cell sheet to provide additional protection (thickness) to the lining, the device is not suited to laparoscopic application. We have developed and tested a new device and procedure that can be used laparoscopically to adhere cell sheets to organs., Sensors and Materials, 33(3), pp. 973-979; 2021

We are currently developing a mobile scaffolding device that can dodge the piers of bridges without dismantling the scaffold when moving between spans to improve efficiency and safety in bridge inspections. The mobile scaffolding device treated in this paper is split in the center of the device when it crosses the piers. In this process, the mobile scaffold is cantilevered and poses a danger to the workers on board. Therefore, we implemented horizontal holding control by wire reeling to keep the mobile scaffold horizontal. However, in this control method, the direction of motion of the mobile scaffold is only partially constrained by the wire. Thus, the device is greatly excited when an external force is applied. It is difficult to damp these oscillations in wire-reeling control. We designed a semi-active dynamic absorber for vibration control by applying the skyhook theory, a basic theory of the active suspension. When a random input that simulates the wind force was given to the mobile scaffolding device with the dynamic absorber, the vibration of the device was reduced by half compared with that of the mobile scaffolding device without the dynamic absorber., Sensors and Materials, 33(3), pp. 959-972; 2021

A path planning algorithm for an Autonomous Underwater Vehicle (AUV) performing docking operations in the presence of tidal current disturbances is presented. The path planner is composed a way-point generator (WPG), an Model Predictive Control based optimal planner (OP), and a tidal current estimator (TCE). The WPG defines the next way-point with respect to the vehicle position and the OP iteratively generates the trajectory over a prescribed future horizon whilst satisfying certain physical and logical constraints. The TCE estimates the tidal current disturbance speed enabling to adapt the AUV trajectory for reducing actuators power consumption. The proposed path planning policy has been evaluated in a set of simulation scenarios to illustrate the ability of the policy to drive the AUV by satisfying specifications and limiting power consumption.

Internet usage has become an essential part of our daily lives, it has become universal. The aim of this research is to consider existing Internet-based networks with regard to their support for the remote operation of robotic technology, in particular, looking at transmission speed and delay time as it relates to teleoperation. Currently dedicated connections are typically used when a high Quality of Service (QoS) is required for mission critical services or safety-critical systems (SCS), however such connections are very expensive to set up and maintain. Therefore, this study focuses on modifying existing internet networks in a manner to provide a better QoS with little additional cost. Using a number of microcontrollers, computers, and routers, two different protocols were used to control a robotic device remotely. Use of the Point-to-Point Tunnelling Protocol (PPTP) used for implementing a Virtual Private Network (VPN) was found to provide higher average transmission speeds compared to the using a Uniform Resource Locator (URL) which is a regular internet connection.

Food consumption is increasing as the world population increases. While the eating of fish is spreading worldwide, the depletion of fishery resources has become a problem owing to overfishing, and the importance of aquaculture is increasing in order to continue to supply fish as food. In marine aquaculture, fish are grown in aquaculture cages in the sea. Thus, if a harmful algal bloom (HAB) reaches the cages, it will cause serious damage. Countermeasures against HAB are one of the important problems for aquaculture fishermen. In Nagasaki Prefecture in Japan, countermeasures against HAB include patrolling and sampling water by ships. These samples are then submitted to HAB experts for analysis. Following this analysis, notification is provided to aquaculture fishermen. When HAB is detected early, aquaculture fishermen can minimize the damage of HAB by stopping feeding and moving the aquaculture cages. In this study, we developed a system of early detection and notification of HAB to aquaculture fishermen. This is carried out by patrolling and sampling water using drones, detection of HAB by microscope and PC operation, and automatic notification by email and web application. As a result of this developed system, the identification accuracy of harmful plankton is more than 90%, and the time taken to find HABs can be shortened from the 6 h of the conventional approach to 15 min using this newly developed system., Sensors and Materials, 31(12), pp.4155-4171; 2019

Objectives. Thoracic drainage is a common procedure to drain fluid, blood, or air from the pleural cavity. Some attempts to develop approaches to new thoracic drainage systems have been made; however, a simple tube is often currently used. The existing drain presupposes that it is placed correctly and that the tip does not require moving after insertion into the thoracic cavity. However, in some cases, the drain is not correctly placed and reinsertion of an additional drain is required, resulting in significant invasiveness to the patient. Therefore, a more effective drainage system is needed. This study aimed to develop and assess a new thoracic drain via a collaboration between medical and engineering personnel. Methods. We developed the concept of a controllable drain system using magnetic actuation. A dry laboratory trial and accompanying questionnaire assessment were performed by a group of thoracic and general surgeons. Objective mechanical measurements were obtained. Porcine experiments were also carried out. Results. In a dry laboratory trial, use of the controllable drain required significantly less time than that required by replacing the drain. The average satisfaction score of the new drainage system was 4.07 out of 5, indicating that most of the research participants were satisfied with the quality of the drain with a magnetic actuation. During the porcine experiment, the transfer of the tip of the drain was possible inside the thoracic cavity and abdominal cavity. Conclusion. This controllable thoracic drain could reduce the invasiveness for patients requiring thoracic or abdominal cavity drainage.

A control system for driving an Autonomous Underwater Vehicle (AUV) performing docking operations in presence of tidal current disturbances is proposed. The nonlinear model of the vehicle has been modelled in a Linear Parameter-Varying (LPV) form. This is suitable for the design of the control system using a model-based approach. The LPV model was used for a Model Predictive Control (MPC) design for computing the set of forces and moments driving the nonlinear vehicle model. The LPV-MPC control action is mapped into the reference signals for the actuators by using a Thrust Allocation (TA) algorithm. This was based on the nonlinear models for the actuators and their position and orientation on the vehicle’s hull. The structural decomposition of MPC and TA reduces the computational burden involved in computing the control law on-line on an embedded control board. Both MPC and TA algorithms use the vehicle’s linear and angular positions, and velocities that are estimated by an LPV based Kalman Filter (KF). The proposed control system has been tested in different docking scenarios using various tidal current disturbances acting on the vehicle as an unmeasured disturbance. The simulation results show the controller is effective in controlling the AUV over the range of control scenarios meeting the constraints and specifications.

Synthetic fibre ropes are in widespread use in maritime applications ranging from lifting to temporary and permanent mooring systems for vessels, fish farm, offshore equipment and platforms. The selection of synthetic ropes over conventional steel components is motivated by several key advantages including selectable axial stiffness, energy absorption and hence load mitigation, fatigue resistance and low unit cost. The long-term use of ropes as safety critical components in potentially high dynamic loading environments necessitates that new designs are verified using stringent qualification procedures. The International Organization for Standardization (ISO) is one certification body that has produced several guidelines for the testing of synthetic ropes encompassing quasi-static and dynamic loading as well as fatigue cycling. The paper presents the results of tension-tension tests carried out to ISO 2307:2010, ISO 18692:2007(E) and ISO/TS 19336:2015(E) on 12-strand rope with embedded electric cable constructions manufactured by Ashimori Industry Co. Ltd from Vectran fibres. The purpose of the tests was to characterise the performance of a novel strand construction (SSR) and compare this to a conventional 12-strand construction. Utilising the Dynamic Marine Component test facility (DMaC) at the University of Exeter several key performance metrics were determined including; elongation, minimum break load (MBL), quasi-static, dynamic stiffness and embedded cable resistance. During the ISO 2307:2010(E) test programme the samples were tested dry and during the ISO 18692:2007(E) and ISO/TS 19336:2015(E) test programmes the samples were fully submerged in tap water after being soaked in water for at least 24 hours. Two methods were used to quantify sample extension: i) an optical tracking system and ii) a potentiometer. Axial compression fatigue and cyclic loading endurance tests were also carried out on Vectran sample. Failure of the Vectran sample or embedded cable did not occur during tests carried out using DMaC. Further tests and sample analysis were also carried out by Ashimori Industry Co. Ltd. Quasi-static bedding-in at 50% MBS and cyclic load endurance test with 6000 cycles between 3.57% MBS and 53.6% MBS was completed. The Effective Working Length (EWL) was 3.821 m before testing and 3.974m after testing. The resistance of the cable increased from 9.6962 Ω to 9.7693Ω during the test and importantly the embedded cable did not fail. Each tensile loading cycle of the rope caused a measurable variation in wire resistance; approximately 0.01Ω. The data obtained during these tests will provide insight into the behaviour of these materials, which will be of use to rope manufacturers and mooring system designers, in addition to offshore equipment and vessel operators.

The purpose of the present study was to identify the structures of cannabidiol (CBD) metabolites during CO formation by human liver microsomes and human recombinant cytochrome P450 (CYP) enzymes. CBD was NADPH-dependently metabolized by human liver microsomes and human recombinant CYP enzymes. Less-polar metabolites were analyzed by gas chromatography–mass spectrometry monitoring, and their estimated molecular ions were m/z 286, 358 and 481 after non-derivatization, trimethylsilylation and pentafluorobenzyl oxime formation, respectively. We tentatively identified novel decarbonylated metabolites of CBD as keto-enol tautomers. Among eight major recombinant human CYP enzymes, only CYP3A4 catalyzed the formation of decarbonylated metabolites. CBD was biotransformed to two decarbonylated metabolites, an enol-form (cyclopentadienol structure), and a keto-form (cyclopentenone structure) by human liver microsomes and CYP3A4.

We previously reported the diversity of structure and integration sites of human T-cell leukemia virus type 1 (HTLV-1) provirus among different MT-2 cell lines. This raised the question as to whether cell phenotypes also differed among MT-2 cell lines. The influence of two different MT-2 cell lines (MT-2J and MT-2B) on the growth of the promonocytic leukemia cell line, U937, was investigated. Protein levels and mRNA expression of cytokines were also investigated. In addition, Western blot analysis of HTLV-1 regulatory proteins, Tax and HBZ, was also performed. Culture supernatant from MT-2B, but not MT-2J, cells showed marked suppressive effects on U937 cell growth. MT-2B showed high tumor necrosis factor (TNF)-α, TNF-β, and interferon (IFN)-γ both in protein levels of the culture supernatant and mRNA levels of the cells. Analysis using recombinant cytokines indicated that the suppressive effects of MT-2B were due, at least in part, to high levels of TNF-β and its synergic effects with IFN-γ in the culture supernatant. Protein levels of HTLV-1 Tax and HBZ were higher in MT-2B than those in MT-2J cells. These molecules have been reported to affect the cytokine production of HTLV-1 infected cells; therefore, the difference in these molecules may have accounted for the differences in cytokine production between MT-2J and MT-2B cells. Furthermore, because MT-2 cells showed a large variation of integrated HTLV-1 proviruses as well as cell phenotypes, it is important to exercise caution in the assessment and interpretation of experimental data from MT-2 cells.

∆9-Tetrahydrocannabinol (∆9-THC) and cannabidiol (CBD), major psychoactive constituents of marijuana, induce potentiation of pentobarbital-induced sleep in mice. We have elucidated the mechanism of enhancement of the anesthetic effect of pentobarbital by cannabinoids. We carried out pharmacological experiment and cannabinoid1 (CB1) receptor binding assay using CB1 antagonists to clarify whether the CB1 receptor is involved in the synergism or not. The affinities of cannabinoids for the CB1 receptor in the mouse brain synaptic membrane were evaluated using a specific CB1 ligand, [3H]CP55940. Although the potentiating effect of ∆9-THC on pentobarbital-induced sleep was attenuated by co-administration of CB1 receptor antagonists, such as SR141716A and AM251, at a dose of 2 mg/kg, intravenously (i.v.) to mice, the CBD-enhanced pentobarbital-induced sleep was not inhibited by SR141716A. The inhibitory constant (Ki) values of ∆9-THC and CBD were 6.62 and 2010 nM, respectively, showing a high affinity of ∆9-THC and a low affinity of CBD for the CB1 receptor, respectively. A high concentration of pentobarbital (1 mM) did not affect specific [3H]CP55940 binding on the mouse brain synaptic membrane. These results suggest that binding of ∆9-THC to the CB1 receptor is involved in the synergism with pentobarbital, and that potentiating effect of CBD with pentobarbital may differ from that of ∆9-THC. We successfully demonstrated that ∆9-THC enhanced the anesthetic effect of pentobarbital through the CB1 receptor.

Objectives. In recent years, video-assisted thoracoscopic surgery (VATS) has increasingly become the preferred technique for thoracic surgery. However, the inherent characteristics of the lungs as large, soft, slippery, and delicate creates difficulties for pulmonary surgery. In this article, we outline the development and assessment of a balloon-based organ retractor for VATS via collaboration between medical and engineering personnel. Methods. A dry lab trial and accompanying questionnaire assessment were performed by a group of thoracic surgeons. Objective pressure measurements were obtained, and animal experiment on pigs was performed. Results. In the dry lab trial, use of the developed organ retractor required significantly less time and resulted in fewer difficulties than using a Cherry Dissector. The measured pressure per mm2 of the developed retractor was clearly lower than that for the Cherry Dissector. The questionnaire completed by the surgeons following the dry lab and animal experiments showed that most of the surgeons (7 surgeons out of 9) were satisfied with the quality of the balloon-based retractor based on a score of 3.13 ± 0.28 (mean ± standard deviation) out of 4.0. During the animal experiment, the balloon-based retractor provided stable and clear viewing with minimal need for adjustment. Conclusion. This balloon-based retractor could contribute to increased safety and less-invasive VATS.