Статті в журналах: "Non-Manual Transmissions"

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Qi, Xiaowei, Yiyong Yang, Xiangyu Wang, and Zaobei Zhu. "Analysis and optimization of the gear-shifting process for automated manual transmissions in electric vehicles." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 231, no. 13 (January 27, 2017): 1751–65. http://dx.doi.org/10.1177/0954407016685461.

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In recent years, it has been a trend for an automated manual transmission to be adopted as the powertrain for an electric vehicle. However, the strong degrees of jerk and power interruption during the gear-shifting process affect the shifting quality and restrict the application of automated manual transmissions. Therefore, it is a currently popular research topic to find an optimal method to improve the shifting qualities of automated manual transmissions. In this paper, the clutchless shifting process is analysed on the basis of a dynamics model of an automated manual transmission in an electric vehicle, and the parameters are optimized to improve the shifting quality using a defined comprehensive evaluation index. First, the dynamics model of the shifting process for an automated manual transmission is established by considering the stiffness, the damping and the non-linearity contact backlash of the gear mesh and the synchronizer. The whole shifting process is carried out in MATLAB/Simulink and compared with that in the Adams model and bench experiments to prove the accuracy of the dynamics model. Then, the factors of the shifting quality, which include the shifting force and the control accuracy of the speed of the driving motor, are quantified. With the comprehensive evaluation index, all the main factors are described in a cobweb model diagram to find the optimal parameters of the shifting process. The results show that the comprehensive evaluation index can be reduced by 23% by regulating the parameters of the shifting process. This study may be conducive to improving the shifting quality of automated manual transmissions in electric vehicles.

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Hedman, A. "Transmission Analysis—Automatic Derivation of Relationships." Journal of Mechanical Design 115, no. 4 (December 1, 1993): 1031–37. http://dx.doi.org/10.1115/1.2919252.

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A method for derivation of relationships for general mechanical transmission systems is given. It is adapted for computer-aided analysis and synthesis of the kinematics, loads, and power flows. Losses are included. All relationships are handled by a computer program. No manual dealing with equations is necessary. The user only describes the transmission systems: (1) The transmission units, e.g., gear transmissions, planetary gear trains, clutches and input shafts. (2) How the shafts of those units are connected. Then, the computer program formulates the relationships, and a computer algebra program performs algebraic eliminations. Symbolic, non-numerical, relationships between speeds and torques of two arbitrary shafts can be derived, e.g., the overall efficiency. Special algorithms handle the power flows in split-power transmissions. The method saves time and eliminates the risk for human errors.

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Wang, Michael Yu, Weijie Zhao, and Radhakrishnan Manoj. "Numerical Modelling and Analysis of Automotive Transmission Rattle." Journal of Vibration and Control 8, no. 7 (July 2002): 921–43. http://dx.doi.org/10.1177/10775402029594.

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This paper describes a research work on modelling and numerical analysis of torsional vibration in automotive manual transmissions. The focus of the effort is on a decoupling procedure for the numerical analysis of gear rattle. The power train model is specified into a linear sub-system and a non-linear sub-system that includes the strong nonlinearities of gear backlash and multi-stage clutch stiffness. The weak coupling of the sub-systems is then exploited for efficient numerical analysis. It is shown that the decoupled model yields an acceptable accuracy with a significant gain in computational efficiency when using an algorithm of numerical integration of stiff differential equations or a finite element in time algorithm. Numerical simulation results for a Daimler-Chrysler vehicle power train are given to illustrate the effectiveness of the proposed scheme.

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Allam, Abdelrahman, Medhat Moussa, Cole Tarry, and Matthew Veres. "Detecting Teeth Defects on Automotive Gears Using Deep Learning." Sensors 21, no. 24 (December 19, 2021): 8480. http://dx.doi.org/10.3390/s21248480.

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Gears are a vital component in many complex mechanical systems. In automotive systems, and in particular vehicle transmissions, we rely on them to function properly on different types of challenging environments and conditions. However, when a gear is manufactured with a defect, the gear’s integrity can become compromised and lead to catastrophic failure. The current inspection process used by an automotive gear manufacturer in Guelph, Ontario, requires human operators to visually inspect all gear produced. Yet, due to the quantity of gears manufactured, the diverse array of defects that can arise, the time requirements for inspection, and the reliance on the operator’s inspection ability, the system suffers from poor scalability, and defects can be missed during inspection. In this work, we propose a machine vision system for automating the inspection process for gears with damaged teeth defects. The implemented inspection system uses a faster R-CNN network to identify the defects, and combines domain knowledge to reduce the manual inspection of non-defective gears by 66%.

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Brancati, R., E. Rocca, and R. Russo. "A gear rattle model accounting for oil squeeze between the meshing gear teeth." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 219, no. 9 (September 1, 2005): 1075–83. http://dx.doi.org/10.1243/095440705x34757.

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In this paper a non-linear one-degree-of-freedom model for analysis of gear rattle vibrations in automotive manual transmissions is presented. In order to take into account the damping effects owing to the oil in the gap between two teeth of a meshing gear, a simple one-dimensional model for the oil-film squeeze effects is proposed. The squeeze model assumes that the damping force is proportional to the oil viscosity and to the extension of the oil film in the plane of curvature of the teeth, which may depend on the lubrication conditions (dry sump, splash, bath). The results provided from several numerical simulations, carried out with reference to helical involute tooth pairs, confirm the capability of oil in reducing the high-frequency vibrations subsequent to the impact between the teeth. In particular, the influence exerted by oil viscosity and gap extension on the rattle characteristics is investigated through the analysis of the transient response of the driven gear by imposing a harmonic motion to the driving gear.

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Han, Chang-Kyu. "Development of the Non-contacted Gear Detection Sensor for a Manual Transmission." Transactions of the Korean Society of Automotive Engineers 21, no. 5 (September 1, 2013): 1–7. http://dx.doi.org/10.7467/ksae.2013.21.5.001.

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Kocab, Annemarie, Ann Senghas, and Jennie Pyers. "From Seed to System: The Emergence of Non-Manual Markers for Wh-Questions in Nicaraguan Sign Language." Languages 7, no. 2 (May 30, 2022): 137. http://dx.doi.org/10.3390/languages7020137.

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At a language’s inception, what determines which elements are taken up to build a grammar? How is the initial raw material reshaped through intergenerational language learning? We approached this question by focusing on the emergence of non-manual wh-question markers in Nicaraguan Sign Language (LSN), a young sign language. We asked whether the seeds of non-manual markers originate in the facial gestures of the hearing Nicaraguan community, and we explored the iterated process by which a form becomes selected and then systematized through generational transmission. We identified six non-manual facial and body movements produced with questions by 34 deaf LSN signers, representing three sequential age cohorts of learners, and compared them to those produced by 16 non-signing Spanish speakers. We examined the frequency and duration of each non-manual, and its temporal overlap with a question word. One non-manual, the brow furrow, was overwhelmingly represented among LSN signers, despite appearing rarely among non-signers and not being initially favored in duration or temporal overlap. With the second and third cohorts, the brow furrow emerges as a frequent and systematic marker. With each cycle of child learners, variable input was transformed into a more constrained set of grammatical forms.

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Morikane, Keita, Shoko Suzuki, Jun Yoshioka, Jun Yakuwa, and Masaki Nakane. "1214. Microbiological and Clinical Effectiveness of Pulsed-Xenon Ultraviolet Disinfection of the Patient Room in the ICU." Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S436—S437. http://dx.doi.org/10.1093/ofid/ofz360.1077.

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Abstract Background Contact precautions do not necessarily control transmission of MDROs as other route of transmission such as patient environment may be significant. No-touch environmental disinfection has been highlighted in the past several years to control transmission of MDROs. The effectiveness of portable Pulsed Xenon Ultraviolet (PX-UV) device has been examined and demonstrated in US healthcare settings. However, its effectiveness outside the US healthcare setting is seldom reported. Methods This study was conducted in the intensive care unit (ICU) of Yamagata University Hospital, a 637-bed tertiary referral hospital. The ICU has six rooms and beds. In the baseline period (August 2016 to January 2018), all rooms were manually cleaned after every patient transfer/discharge. In the intervention period (February 2018 to February 2019), PX-UV disinfection was added after the manual cleaning. In both periods, all patients were screened for MRSA and two drug-resistant Acinetobacter baumannii (2DRA) to detect acquisition of those pathogens in the ICU. For microbiological evaluation, surfaces were selected for sampling by contact plates before/after manual cleaning and after PX-UV. After overnight incubation, colonies on the plates were counted. Results The incidence of newly acquired MRSA declined over time (1.40 per 1,000 patient-days in the baseline period to 0.95 in the intervention period, relative risk (RR): 0.68, 95% confidence interval (CI): 0.12–3.70). The incidence of newly acquired 2DRA further declined (4.91 to 1.90, RR: 0.39, 95% CI: 0.13–1.18). Notably, no new acquisition of 2DRA was observed since August 2018 for more than 7 months, not only in the ICU but also throughout the hospital. The total count of colonies in the sampling of 140 sites after 17 patient discharges were 3,540 (before manual cleaning), 669 (after manual cleaning, before PX-UV) and 261 (after PX-UV). The percent reduction of microbiological burden by manual cleaning was 81%, but a further 61% reduction was achieved by PX-UV. Conclusion PX-UV is effective in further reducing the microbial burden even after through manual cleaning, which presumably led to termination of transmission of 2DRA in our hospital. The effectiveness of PX-UV in controlling MDROs in the non-US healthcare settings is suggested. Disclosures All authors: No reported disclosures.

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Chandra, Shanel, Joseph Biederman, and Stephen V. Faraone. "Assessing the Validity of the Age at Onset Criterion for Diagnosing ADHD in DSM-5." Journal of Attention Disorders 25, no. 2 (February 27, 2016): 143–53. http://dx.doi.org/10.1177/1087054716629717.

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Objective: Research about Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) age of onset criterion for ADHD led to increasing that criterion to 12 in Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5). Although an improvement from the previous age at onset of 7, whether this new criterion is adequate to capture all cases with ADHD remains uncertain. Method: We compared three groups of adults: (a) ADHD participants who met all DSM-5 criteria for ADHD ( n = 182), (b) late-onset ADHD participants who met all criteria except for later age at onset ( n = 17), and (c) non-ADHD participants who did not meet criteria for ADHD ( n = 117). We assessed patterns of symptoms, psychiatric comorbidity, functional impairment, familial transmission, quality of life, social adjustment, and intelligence. Results: Compared with non-ADHD participants, all ADHD groups had poorer quality of life and had more impaired social adjustment. Compared with each other, the ADHD groups had similar patterns of psychiatric comorbidity, functional impairment, familial transmission, and intelligence. Conclusion: When assessing adult ADHD, self-reported onsets of ADHD after 12 years of age may be warranted.

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Xing, Dongqiu, Lihua Qi, Jing Zhao, and Yi Wang. "The design of computer controlled ground information transmission down platform in drilling." MATEC Web of Conferences 309 (2020): 04017. http://dx.doi.org/10.1051/matecconf/202030904017.

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In order to improve the drilling efficiency and avoid the disadvantages of manual operation, the method of sending the surface intervention instruction with computer instruction is researched. Based on the similarity of liquid flow, a set of hydraulic circulation system is used to simulate the drilling process, selected the key components, designed and built the intelligent drilling system indoor experiment platform; Define different commands with the length of the time and decode them and carried out the sending command experiment. The results show that the platform can successfully send the command to the downhole under the condition of non-stop drilling, which is the attitude intervention, command coding and Weak signal detection in the intelligent drilling system provides a new platform.

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Gonzalez, Jonathan, Thomas Vanzieleghem, Axelle Dumazy, Christelle Meuris, Jacques Mutsers, Genevieve Christiaens, Philippe Leclercq, Jean-Philippe Loly, Edouard Louis, and Pierrette Gast. "On-site comparison of an enzymatic detergent and a non-enzymatic detergent-disinfectant for routine manual cleaning of flexible endoscopes." Endoscopy International Open 07, no. 04 (March 21, 2019): E412—E420. http://dx.doi.org/10.1055/a-0838-4995.

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Abstract Background and study aims Flexible endoscopes are potential vectors of pathogen transmission to patients that are subjected to cleaning and high-level disinfection after each procedure. Efficient manual cleaning is a prerequisite for effective high-level disinfection. The goal of this study was to demonstrate the impact of the cleaning chemistry in the outcome of the manual cleaning of endoscopes. Materials and methods Twelve endoscopes were included in this study: four colonoscopes, four gastroscopes, two duodenoscopes and two bronchoscopes. This study was designed with two phases; in each of them, the manual cleaning procedure remained identical, but a different detergent was used: a non-enzymatic detergent-disinfectant (NEDD) and an enzymatic detergent (ED). Biopsy and suction channels of endoscopes were sampled using 10 mL of physiological saline at two points: before and after manual cleaning, and adenosine triphosphate (ATP) was measured on each sample. In total, 208 procedures were analyzed for the NEDD phase and 253 for the ED phase. Results For each endoscope type, cleaning endoscopes with ED resulted in larger median decrease in ATP than with NEDD: respectively 99.43 % and 95.95 % for bronchoscopes (P = 0.0007), 99.28 % and 96.93 % for colonoscopes (P < 0.0001) and 98.36 % and 95.36 % for gastroscopes (P < 0.0001). In addition, acceptability rates of endoscopes based on defined post-manual cleaning ATP thresholds (200, 150, 100 or 50 relative light units) for all endoscope types were significantly higher with ED compared to NEDD. Conclusions With all other parameters of manual cleaning remaining unchanged, the enzymatic chemistry of ED provided more consistent and improved cleaning of endoscopes compared to NEDD. Therefore, choice of the detergent for endoscope cleaning has an impact on the outcome of this process.

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Mechtenberg, Malte, Nils Grimmelsmann, Hanno Gerd Meyer, and Axel Schneider. "Manual and semi-automatic determination of elbow angle-independent parameters for a model of the biceps brachii distal tendon based on ultrasonic imaging." PLOS ONE 17, no. 10 (October 6, 2022): e0275128. http://dx.doi.org/10.1371/journal.pone.0275128.

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Tendons consist of passive soft tissue with non linear material properties. They play a key role in force transmission from muscle to skeletal structure. The properties of tendons have been extensively examined in vitro. In this work, a non linear model of the distal biceps brachii tendon was parameterized based on measurements of myotendinous junction displacements in vivo at different load forces and elbow angles. The myotendinous junction displacement was extracted from ultrasound B-mode images within an experimental setup which also allowed for the retrieval of the exerted load forces as well as the elbow joint angles. To quantify the myotendinous junction movement based on visual features from ultrasound images, a manual and an automatic method were developed. The performance of both methods was compared. By means of exemplary data from three subjects, reliable fits of the tendon model were achieved. Further, different aspects of the non linear tendon model generated in this way could be reconciled with individual experiments from literature.

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Saikrishna, U., K. Srinivas, and Y. L. V. D. Prasad. "Development of Guided Wave Ultrasonic Inspection Method for Thick Composite Structures." Applied Mechanics and Materials 592-594 (July 2014): 153–57. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.153.

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Ultrasonic Non-destructive testing is a well known technique for inspecting fiber reinforced composite structures however; its capability is severely limited by the high attenuation in thick and multi layer structures. Guided wave ultrasonic inspection has been reported to be useful tool for quantitative identification of composite structures. It takes advantage of tailoring / generating desired ultrasonic wave modes (Symmetric and anti-symmetric) for improved transmission through the composite structure. For this, guided waves have to be generated selectively by precisely placing transducer at an angle to the test surface. Automation of two axis fixture for transmission and reception of transducers have to be used for avoiding manual errors. The captured signals have to be processed in order to extract useful information from the received ultrasonic signals. The proposed project aims at developing automated guided wave inspection methods along with digital signal processing for generating dispersion curves for thick composited. Using test laminates with implanted defects, methodology for thick composite inspection with guided wave ultrasonic’s will be established. For this data will be captured and analyzed using Labview software.

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Bowler, Alexander, Josep Escrig, Michael Pound, and Nicholas Watson. "Predicting Alcohol Concentration during Beer Fermentation Using Ultrasonic Measurements and Machine Learning." Fermentation 7, no. 1 (March 4, 2021): 34. http://dx.doi.org/10.3390/fermentation7010034.

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Beer fermentation is typically monitored by periodic sampling and off-line analysis. In-line sensors would remove the need for time-consuming manual operation and provide real-time evaluation of the fermenting media. This work uses a low-cost ultrasonic sensor combined with machine learning to predict the alcohol concentration during beer fermentation. The highest accuracy model (R2 = 0.952, mean absolute error (MAE) = 0.265, mean squared error (MSE) = 0.136) used a transmission-based ultrasonic sensing technique along with the measured temperature. However, the second most accurate model (R2 = 0.948, MAE = 0.283, MSE = 0.146) used a reflection-based technique without the temperature. Both the reflection-based technique and the omission of the temperature data are novel to this research and demonstrate the potential for a non-invasive sensor to monitor beer fermentation.

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Rawool, Vishakha. "Skin conductance during remote collaborative communication under noisy, reverberant and delayed communication transmission conditions." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A196. http://dx.doi.org/10.1121/10.0016006.

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This study, which is part of a larger study, was designed to monitor skin conductance during remote collaborative communication. Ninety (45 men and 45 women) participants were divided into 30 teams with three members in each team. Each team built different LEGO models under three communication transmission delay conditions in the following order: No delay, 750 ms delay and 5000 ms delay. One individual served as the LEGO builder, who did not have the instruction manual. The remaining two team members provided instructions for building the models. Participants were in separate rooms and communicated via earphones. Background white noise (50 dB SPL) was introduced in the ear canals and reverberation was applied to the transmitted communication. Participants were fitted with Empatica E4 wristbands. The ANOVA revealed that the Sum of non-specific skin conductance response (NS-SCR) amplitude/minute was significantly reduced in the 5000 ms delay condition compared to the No delay and 750 ms delay conditions with a medium effect size. These results suggest that participants tend to adapt to the task yielding reduced stress in the last delay condition. Acknowledgement: Graduate students Sydney Osbarn and Melissa Reyes assisted in data collection. Sydney Osbarn also assisted in pre-processing the data.

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Rafiq, Arif Ainur, Erna Alimudin, and Della Puspa Rani. "Employee Presence Using Body Temperature Detection and Face Recognition." International Journal of Applied Sciences and Smart Technologies 4, no. 2 (December 21, 2022): 173–84. http://dx.doi.org/10.24071/ijasst.v4i2.5066.

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Employee performance can be measured by their presence or attendance, which applies to both civil servants and non-civil servants. Because the attendance system still uses the manual technique, it is considered inefficient due to the potential for data fraud and attendance problems. In addition, the government is adopting precautions against viruses in office buildings to maintain business continuity while the pandemic is being addressed. The goal of this study was to employ a facial recognition system and temperature measurement to lower the danger of COVID 19 transmission while also minimizing paper use by using a facial recognition system as a substitute for presences. It has so far permitted the digitization of formerly manual sights. The OpenCV library allows computers to detect faces using the haar cascade classifier approach and Python as a programming language. A Logitech C930e webcam with a resolution of 1080p at 30fps was used to capture facial data, which was then processed on a Raspberry Pi 4 microprocessor. It uses an MLX90614 sensor to monitor body temperature, which is controlled by anArduino Uno microcontroller. It is well integrated into the database based on body temperature testing and facial recognition. The development of a more accurate temperature sensor reading method for distance and employee body temperature is a priority for future research.

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Lasheras, Isabel, Patricia Gracia-García, Darren Lipnicki, Juan Bueno-Notivol, Raúl López-Antón, Concepción de la Cámara, Antonio Lobo, and Javier Santabárbara. "Prevalence of Anxiety in Medical Students during the COVID-19 Pandemic: A Rapid Systematic Review with Meta-Analysis." International Journal of Environmental Research and Public Health 17, no. 18 (September 10, 2020): 6603. http://dx.doi.org/10.3390/ijerph17186603.

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The novel coronavirus disease (COVID-19) pandemic has brought a great deal of pressure for medical students, who typically show elevated anxiety rates. Our aim is to investigate the prevalence of anxiety in medical students during this pandemic. This systematic review and mini meta-analysis has been conducted following the PRISMA guidelines. Two researchers independently searched PubMed on 26 August 2020 for cross-sectional studies on medical students during the COVID-19 outbreak, with no language restrictions applied. We then performed a manual search to detect other potentially eligible investigations. To the 1361 records retrieved in the initial search, 4 more were added by manual search on medRxiv. Finally, eight studies were finally included for qualitative and quantitative analysis, which yielded an estimated prevalence of anxiety of 28% (95% CI: 22–34%), with significant heterogeneity between studies. The prevalence of anxiety in medical students is similar to that prior to the pandemic but correlates with several specific COVID-related stressors. While some preventive and risk factors have been previously identified in a non-pandemic context, knowledge and cognitions on COVID-19 transmission, treatment, prognosis and prevention negatively correlate with anxiety, emerging as a key preventive factor that may provide a rationale for why the levels of anxiety have remained stable in medical students during the pandemic while increasing in their non-medical peers and the general population. Other reasons for the invariability of anxiety rates in this population are discussed. A major limitation of our review is that Chinese students comprised 89% the total sample, which could compromise the external validity of our work

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Aoyagi, Seiji, Masato Suzuki, Tomokazu Takahashi, Jun Fujioka, and Yoshitsugu Kamiya. "Calibration of Kinematic Parameters of Robot Arm Using Laser Tracking System: Compensation for Non-Geometric Errors by Neural Networks and Selection of Optimal Measuring Points by Genetic Algorithm." International Journal of Automation Technology 6, no. 1 (January 5, 2012): 29–37. http://dx.doi.org/10.20965/ijat.2012.p0029.

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Offline teaching based on high positioning accuracy of a robot arm is desired to take the place of manual teaching. In offline teaching, joint angles are calculated using a kinematic model of the robot arm. However, a nominal kinematic model does not consider the errors arising in manufacturing or assembly, not to mention the non-geometric errors arising in gear transmission, arm compliance, etc. Therefore, a method of precisely calibrating the parameters in a kinematic model is required. For this purpose, it is necessary to measure the three-dimensional (3-D) absolute position of the tip of a robot arm. In this paper, a laser tracking system is employed as the measurement apparatus. The geometric parameters in the robot kinematic model are calibrated by minimizing errors between the measured positions and the predicted ones based on the model. The residual errors caused by non-geometric parameters are further reduced by using neural networks, realizing high positioning accuracy of sub-millimeter order. To speed up the calibration process, a smaller number of measuring points is preferable. Optimal measuring points, which realize high positioning accuracy while remaining small in number, are selected using Genetic Algorithm (GA).

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Wiese, Inga, Anja Kurzhals, Grit Rhinow, Carsten Tautorat, Frank Kamke, Christoph Brandt-Wunderlich, Klaus-Peter Schmitz, Niels Grabow, and Wolfram Schmidt. "Automation of online particle measurement during the simulated use of catheters and stent systems." Current Directions in Biomedical Engineering 7, no. 2 (October 1, 2021): 648–51. http://dx.doi.org/10.1515/cdbme-2021-2165.

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Abstract The assessment of the coating integrity of cardiovascular implants such as catheters and stent systems is of crucial importance for device approval. Released particles may represent a potential health risk for the patients. Thus, an analysis of the particles released at simulated in-vivo conditions depending on their size and number is required by international standards (ISO, ASTM) as well as national authorities. In this study, an automated test bench for online particle measurement is presented. For software controlled automation, sensor data transmission and solenoid valves were implemented. A user interface was created for setting test parameters and data recording. The setup was validated by investigating standard particles as well as those released during the simulated application of non-industrial coated balloons. The measurement data were compared with results generated using the previous manual test routine. The results show an improvement in the reproducibility of the measurements, which can be attributed to the simplified handling for the user.

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Wang, Jinpeng, Haotian Liu, Qingxue Yao, Jeremy Gillbanks, and Xin Zhao. "Research on High-Throughput Crop Root Phenotype 3D Reconstruction Using X-ray CT in 5G Era." Electronics 12, no. 2 (January 5, 2023): 276. http://dx.doi.org/10.3390/electronics12020276.

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Currently, the three-dimensional detection of plant root structure is one of the core issues in studies on plant root phenotype. Manual measurement methods are not only cumbersome but also have poor reliability and damage the root. Among many solutions, X-ray computed tomography (X-ray CT) can help us observe the plant root structure in a three-dimensional and non-destructive form under the condition of underground soil in situ. Therefore, this paper proposes a high-throughput method and process for plant three-dimensional root phenotype and reconstruction based on X-ray CT technology. Firstly, this paper proposes a high-throughput transmission for the root phenotyping and utilizing the imaging technique to extract the root characteristics; then, the study adopts a moving cube algorithm to reconstruct the 3D (three-dimensional) root. Finally, this research simulates the proposed algorithm, and the simulation results show that the presented method in this paper works well.

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Lee, C.-K., and C.-K. Chen. "Mathmathematical models, meshing analysis and transmission design for a robust cylindrical gear set generated by two blade-discs with parabolic cutting edges." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 218, no. 12 (December 1, 2004): 1539–53. http://dx.doi.org/10.1243/0954406042690498.

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This paper proposes mathematical models for analysing meshing characteristics and controlling a parabolic-like kinematic error function for a newly developed cylindrical gear set generated by two blade-discs with parabolic cutting edges. Unlike the former design, the proposed gear set is robust against assembly errors owing to its localized bearing contact and parabolic-like kinematic error function. Based on the proposed systematic mathematical procedures, the dimension of major axis of contact ellipse and magnitude of kinematic error can be controlled by the parameters of the blade-discs. To avoid gear undercutting, explicit functions of minimum numbers of teeth of non-undercutting for gear and pinion are derived. Equations for analysing tooth contact status, specific slide and contact ellipse are created. Based on the proposed mathematical models, a computer program has been established to analyse the effects of variation in parameters for cutting tools on meshing characteristics. The robustness of the developed gear set against various assembly errors is verified through numerical examples. With the proposed mathematical models and the computer program, gear designers can quickly determine the values of parameters for cutting tools without manual trial-and-error procedures.

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Irfan, Sarah, Seema Irfan, Mubassar Fida, and Israr Ahmad. "Contamination assessment of orthodontic bands after different pre-cleaning methods at a tertiary care hospital." Journal of Orthodontics 46, no. 3 (June 13, 2019): 220–24. http://dx.doi.org/10.1177/1465312519855402.

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Introduction: Infection control in dentistry is a major concern due to risk of transmission of communicable diseases. The aim of this study is to evaluate and compare the efficacy of various pre-cleaning methods for the tried-in orthodontic bands. Material and methods: An in-vitro experimental study was conducted at the Central Sterilization Services Department (Dental Clinic) and the Microbiology lab at our university hospital. A total of 130 bands were included in our study which comprised 10 controls and the rest were equally divided into three groups according to the pre-cleaning methods, i.e. manual scrubbing, enzymatic solution and a combination of both. The orthodontic bands were incubated in the brain heart infusion broth at 37 °C for five days after pre-cleaning and sterilisation in a steam autoclave and were assessed for any bacterial growth. The chi-square test was applied to determine any significant association between the various pre-cleaning methods and the frequency of bands that showed growth. Effect size was calculated using the phi coefficient. Results: The enzyme method revealed 5% of the sample to exhibit bacterial growth, whereas manual scrubbing and the combination of both showed no growth. There was no statistically significant difference among the three methods ( P = 0.131). Further investigations showed the presence of Staphylococcus non-aureus bacterial species in contaminated bands from group II. Conclusions: All pre-cleaning methods were found to be equally effective in the decontamination of bands. Hence, the tried-in bands can be safely reused after pre-cleaning and sterilisation.

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Oblinger, Christian, André Baeten, and Klaus Drechsler. "Experimental Characterization of the Fiber Angles of Multiple Curved Laminate Segments Using Prepreg-Based Carbon Fiber Reinforced Polymers as a Structure for a Non-Engaging Bellows Coupling." Key Engineering Materials 809 (June 2019): 555–62. http://dx.doi.org/10.4028/www.scientific.net/kem.809.555.

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This paper deals with the experimental characterization of the fiber angles of multiple curved laminate segments using prepreg-based carbon fiber reinforced polymers as a structure for a non-engaging bellows coupling. The main task of this generic shaft coupling is the torsionally stiff torque transmission and the compensation of axial displacement as well as the angular misalignment of metallic shafts. The multiple curved structure can be manually draped by several cut segments using epoxy-based fabric prepreg. Moreover, the intended initial fiber orientation of the laminate is ±45° with respect to the rotation axis of the structure. For the experimental determination of the local fiber angles various CFRP cut segments were defined as CFRP specimens with varying number of layers and constant width. All investigations were based on cured CFRP specimens. The measurements were performed with a robot-assisted optical surface sensor and an optical digital microscope. The influence of the manual draping process according to the z-method could be quantitatively determined by the fiber angle measurements.

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24

Miller, David. "Sperm RNA as a Mediator of Genomic Plasticity." Advances in Biology 2014 (October 14, 2014): 1–13. http://dx.doi.org/10.1155/2014/179701.

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Sperm RNA has been linked recently to trans-generational, non-Mendelian patterns of inheritance. Originally dismissed as “residual” to spermatogenesis, some sperm RNA may have postfertilization functions including the transmission of acquired characteristics. Sperm RNA may help explain how trans-generational effects are transmitted and it may also have implications for assisted reproductive technologies (ART) where sperm are subjected to considerable, ex vivo manual handling. The presence of sperm RNA was originally a controversial topic because nuclear gene expression is switched off in the mature mammalian spermatozoon. With the recent application of next generation sequencing (NGS), an unexpectedly rich and complex repertoire of RNAs has been revealed in the sperm of several species that makes its residual presence counterintuitive. What follows is a personal survey of the science behind our understanding of sperm RNA and its functional significance based on experimental observations from my laboratory as well as many others who have contributed to the field over the years and are continuing to contribute today. The narrative begins with a historical perspective and ends with some educated speculation on where research into sperm RNA is likely to lead us in the next 10 years or so.

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Patton, Michaela, Mehak Stokoe, Caitlin Forbes, Chidera Nwaroh, Melanie Noel, Kathleen Reynolds, and Fiona Schulte. "The Intergenerational Transmission of Chronic Pain from Parents to Survivors of Childhood Cancer." Children 7, no. 11 (November 21, 2020): 246. http://dx.doi.org/10.3390/children7110246.

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Background: Among youth with chronic non-cancer pain, 50% have parents with chronic pain. These youth report significantly more pain interference and posttraumatic stress symptoms (PTSS), and worse health-related quality of life (HRQL) than youth whose parents do not have chronic pain. Additionally, parent chronic pain is linked to increased child anxiety and depressive symptoms. Survivors of childhood cancer (SCCs) are at risk of pain and negative psychosocial outcomes and therefore may be especially vulnerable if their parents have chronic pain. Thus, the aims of the current study were to (1) identify rates of chronic pain among parents of SCCs, (2) test group differences in psychological symptoms in parents with chronic pain versus without, and (3) test group differences in pain interference, HRQL, anxiety, depression, and PTSS in SCCs with parents with chronic pain versus without. Methods: 122 SCCs (Mean age = 15.8, SD = 4.8, 45.7% male, Mean age at diagnosis = 5.9, SD = 4.7) and their parents were recruited from across Canada to complete online questionnaires. Parents were asked if they have had pain for at least three consecutive months and completed the brief symptom inventory (BSI) as a measure of psychological symptomatology. Survivors completed the pain questionnaire, patient reported outcomes measurement information system (PROMIS)—pain interference, anxiety, and depression measures, child posttraumatic stress scale, posttraumatic stress disorder checklist for the Diagnostic and Statistical Manual of Mental Disorders, and the pediatric quality of life inventory. Results: Forty-three (39%) parents of SCCs reported having chronic pain. Of the 29 survivors who had chronic pain, 14 (48%) also had parents with chronic pain. Parents with chronic pain reported significantly higher scores on the BSI than parents without chronic pain, F(1, 116) = 5.07, p = 0.026. SCCs with parents with versus without chronic pain reported significantly higher PTSS F(1, 105) = 10.53, p = 0.002 and depressive symptoms F(1, 102) = 6.68, p = 0.011. No significant differences were found across the other variables tested. Conclusions: Findings suggest that survivors’ parents’ own pain is prevalent and is related to survivors’ increased depressive symptoms and PTSS, but not anxiety, pain interference, or HRQL. Future research should explore whether parents may benefit from psychological intervention after their child has been diagnosed with cancer and how this could improve outcomes for their child.

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Sawalha, M. S., C. Brierley, and E. Atwell. "Prosody prediction for arabic via the open-source boundary-annotated qur’an corpus." Journal of Speech Sciences 2, no. 2 (February 4, 2021): 175–91. http://dx.doi.org/10.20396/joss.v2i2.15038.

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humans or machines. To develop phrase break classifiers, we need a boundary-annotated and part-ofspeech tagged corpus. Boundary annotations in English speech corpora are descriptive, delimiting intonation units perceived by the listener; manual annotation must be done by an expert linguist. For Arabic, there are no existing suitable resources. We take a novel approach to phrase break prediction for Arabic, deriving our prosodic annotation scheme from Tajwid (recitation) mark-up in the Qur’an which we then interpret as additional text-based data for computational analysis. This mark-up is prescriptive, and signifies a widely-used recitation style, and one of seven original styles of transmission. Here we report on version 1.0 of our Boundary-Annotated Qur’an dataset of 77430 words and 8230 sentences, where each word is tagged with prosodic and syntactic information at two coarse-grained levels. We then use this dataset to train, test, and compare two probabilistic taggers (trigram and HMM) for Arabic phrase break prediction, where the task is to predict boundary locations in an unseen test set stripped of boundary annotations by classifying words as breaks or non-breaks. The preponderance of non-breaks in the training data sets a challenging baseline success rate: 85.56%. However, we achieve significant gains in accuracy with a trigram tagger, and significant gains in performance recognition of minority class instances with both taggers via the Balanced Classification Rate metric. This is initial work on a longterm research project to produce annotation schemes, language resources, algorithms, and applications for Classical and Modern Standard Arabic.

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Yang, In Young, Uk Heo, Kil Sung Lee, Je Woong Park, Young Sub Kweon, David K. Hsu, Young Tae Cho, Chong Ho Lee, and Kwang Hee Im. "Non-Contact and Contact Ultrasonic Detection of Fiber Orientation in Orthotropic Composite Laminates." Key Engineering Materials 324-325 (November 2006): 419–22. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.419.

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Since layup orientation of the laminates greatly influences its properties, an NDE technique for layup orientation determination would be very beneficial. It is desirable to perform contact-less nondestructive evaluation to assess material properties and defects of composites because of permeation of coupling medium such as water. An ultrasonic technique would be very useful, which could be used to test the part after and before curing laminates and requires less time than the optical test. First of all, conventional ultrasonic experimentations were conducted using water as a transmitting medium. In contrast, air-coupled ultrasound is non-contact and has clear advantages over water-coupled testing. Therefore ultrasonic systems for air-coupled and conventional ultrasound were set out for different measurement modalities for acquiring ultrasonic signals as a function of in-plane azimuthal angle. Firstly, a manual scanner was built for making transmission measurements using a pair of normal-incidence shear wave transducers to find the effect of fiber misorientations of orthotropic composite laminates. With the transmitter and receiver on the same side of a laminates, Lamb waves were generated and used for the amplitude magnitude. As a result, it was confirmed that the influence of fiber direction in the laminates could be detected by the non-contacting or contacting inspection from one-side and the detectability was improved by using shaped tube for reducing the specular reflection on transmitting. Furthermore, a vector decomposition model was utilized for lay-up error of the orthotropic laminates. Finally, aircoupled results well corresponded somewhat to those of contact ultrasonic examination in the orthotropic laminates.

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Talalay, Pavel, Xingchen Li, Da Gong, Xiaopeng Fan, Nan Zhang, Yang Yang, Yongwen Liu, Yunchen Liu, Ting Wang, and Xiao Li. "Design and Experiment of Clamper Used in Antarctic Subglacial Bedrock Drilling." Journal of Marine Science and Engineering 7, no. 5 (May 17, 2019): 153. http://dx.doi.org/10.3390/jmse7050153.

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As a result of the severe natural environment with oxygen deficit in the Antarctic, using conventional manual work to screw and unscrew the drill pipe increases the labor intensity tremendously and causes an efficiency reduction. Therefore, it would be useful to design a clamper inside the drilling shelter, which could help to assemble and disassemble the ice core barrel with screw connection. This paper describes the design of and experiments with the clamper inside the movable drilling shelter. A related testing stand was also designed and built to experiment on relationships between the clamper motor current versus clamping torque and force. Through experimental data collation and calculation analysis, the following conclusions could be drawn: (1) according to the rotary ability of the Ice and Bedrock Electromechanical Drill (IBED) to calculate and determine the torque of clamper, the clamping torque required to provide by the clamper is 100 N·m; (2) finite element simulation and analysis of the non-standard transmission chain showed that the mechanical reliability of the subparts; (3) the experimental results showed the range of the clamping force and clamping torque of the clamper. The clamping force and clamping torque increased with the increase of clamper DC motor current, presenting proportional linear relationships. The clamper can meet the clamping requirements of IBED for screwing, unscrewing, and clamping, which will be greatly helpful when it is tested in the field.

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Vece, Gabe, Ricardo M. La Hoz, Cameron R. Wolfe, Emily G. Ward, R. Patrick Wood, Lynne Strasfeld, Rob Sawyer, et al. "88. Public Health Service (PHS) Increased-Risk Factors in Organ Donors: A Review of the OPTN Ad hoc Disease Transmission Advisory Committee (DTAC)." Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S5—S6. http://dx.doi.org/10.1093/ofid/ofz359.012.

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Abstract Background In the United States, all deceased donors (DD) are evaluated for behavioral risk factors for human immunodeficiency virus (HIV), hepatitis B (HBV), and hepatitis C (HCV) infection during the past 12 months. DD with behavioral risk factors or hemodilution are designated as PHS increased risk donors (IRD). Since 2013, the number of IRD has increased from 13.4% of DD to 27% in 2018. Despite a low residual risk of disease transmission after a negative nucleic acid test for HIV/HBV/HCV, the considerable underutilization of IRD has driven an interest in revising the PHS IRD 2013 guidelines. The objective of this study was to describe the epidemiology of IRD with the goal of guiding policy change and maximize organ use. Methods This is a retrospective cohort study of DD during 2018. Characteristics of IRD were compared with non-IRD. A random 10% sample of IRD was selected for manual review of text narratives and donor questionnaires submitted by organ procurement organizations to determine specific PHS IRD factors. Categorical variables were compared using the χ 2 test and continuous variables were compared using a 2-sample t-test for independent samples. Results Among 10,721 DD in 2018, 2,904 were designated IRD (27.1%) with regional variability noted (Figure). Compared with non-IRD, IRD were younger (median age 35 vs. 45 years, P < 0.001) and more often died from drug intoxication (33.2 vs. 5.6%, P < 0.001). Hemodilution was found in 6.8% of all IRD and was the only factor for IRD designation in 60% of pediatric donors <12 years old. The random sample of IRD (N = 288) was similar to IRD population for age, gender, ethnicity, cause of death, and region of recovery (table). Descriptive analysis of the random sample showed that intravenous drug use was the most common behavioral risk factor (N = 124, 43.1%), followed by incarceration (N = 108, 37.5%). Most DD met only 1 criterion (N = 179, 62%); 21% met 2 criteria; and 17% had >3 criteria. Conclusion This study represents the most detailed description of PHS IRD factors since the adoption of the new guidelines in 2013. Understanding the prevalence of factors that lead to IRD designation will help inform future policy development, optimize safe DD use, and increase the number of transplants. Disclosures All Authors: No reported Disclosures.

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Samaranayake, Lakshman, and Sukumaran Anil. "Monkeypox and the dental team." Dental Update 49, no. 8 (September 2, 2022): 683–87. http://dx.doi.org/10.12968/denu.2022.49.8.683.

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Monkeypox (MPX), a rare zoonotic disease, endemic to some African countries is now spreading in non-endemic regions, including the UK. So far, it has been reported in 93 countries with over 38,000 global cases, although the signs are that the disease may be plateauing in UK. The outbreak was declared a public health emergency of international concern by the World Health Organization (WHO). Monkeypox virus (MPXV), belongs to the family Orthopoxviridae, the same family as the smallpox (variola) virus. Although some features of MPX resemble smallpox, a disease that has been eradicated, the former is far milder with a very few associated fatalities. Usually, the initial signs of MPX appear during its prodrome, as single or multiple macular lesions on the oral mucosa, accompanied by generalized lymphadenopathy, followed by the characteristic macular, papular vesicular rash on the skin that heals with scarring. The major mode of spread of MPX is generally through direct or indirect contact with body fluids or lesion material. Its transmission in the dental clinic environment is unlikely if the standard infection prevention and control (IPC) precautions recommended in the National IPC Manual (NHS England) are adhered to. These include wearing N95 masks, fluid-resistant attire and eye protection. Here, the virology, clinical manifestations, diagnosis, management and prevention strategies of MPX, with particular reference to dentistry are reviewed. CPD/Clinical Relevance: To describe the epidemiology of the re-emergent monkeypox outbreak, and discuss the management of dental patients who may present with it.

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Husebye, Eystein S., Bent O. Ruud, and Anton M. Dainty. "Robust and reliable epicenter determinations: Envelope processing of local network data." Bulletin of the Seismological Society of America 88, no. 1 (February 1, 1998): 284–90. http://dx.doi.org/10.1785/bssa0880010284.

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Abstract Local event recordings are complex in the sense that relevant P and S phases vary in an unpredictable manner even between closely spaced stations; thus, manual analysis of such records is still commonplace. Our approach to solving this long-standing problem of observational seismology is to bandpass filter (3 to 6 Hz) to ensure good signal-to-noise ratio SNR and then form envelopes to ensure simple signals across a seismograph network. The physical basis is that Pg and Lg are crustal wave-guide phases reflecting P- and S-energy propagation. Extensive tests on envelope analysis of local records from different areas found that arrival times of the maxima of Pg and Lg envelopes increase very consistently with distance even in different tectonic regimes, typical velocities being 6.1 and 3.5 km/sec, respectively. These arrival-time parameters are easy to extract in a semi-automatic manner and are highly suitable for local epicenter determinations. Extensive tests on locating mining explosions were conducted, and on average, the “envelope” location errors relative to “true” locations were similar to those in bulletins that are based on conventional phase pickings. Occasionally, the Pg/Pn envelope may be very weak but can be replaced by the easily pickable (non-envelope) Pn phase. Additional advantages with envelope locations are transportability (not overly sensitive to details of crustal structure), and that envelope amplitudes can be directly converted to ground motion and magnitudes. For modern stations, envelopes can be formed in situ with low sampling rates of 1 to 2 Hz, thus greatly reducing transmission costs.

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Никишин, К. И. "DEVELOPMENT OF SOFTWARE FOR VALIDATION OF NETWORK STANDARDS." ВЕСТНИК ВОРОНЕЖСКОГО ГОСУДАРСТВЕННОГО ТЕХНИЧЕСКОГО УНИВЕРСИТЕТА, no. 6 (February 8, 2023): 62–67. http://dx.doi.org/10.36622/vstu.2022.18.6.008.

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На сегодняшний день часто используются распределенные сети. К распределенным сетям относятся и беспроводные сети. Для управления автономными объектами как раз используются беспроводные сети. Pассматриваются сетевые стандарты беспроводной связи, в том числе и для работы в беспилотных летательных аппаратах, такие как стандарты IEEE 802.11 и MAVlink, поскольку беспроводные технологии для передачи информации более широко распространены и используются в разных сферах (телекоммуникации, «умный дом», технический мониторинг, «Интернет вещей», беспилотные технологии). Подробно рассматриваются особенности и формат передачи сообщений согласно сетевым стандартам IEEE 802.11 и MAVlink. Для исследования стандартов IEEE 802.11 и MAVLink было разработано специализированное программное обеспечение для валидации данных стандартов, которое обеспечивает посылку сообщений и расшифровывает их отдельно по полям. Проводятся валидация корректности всех блоков передаваемого сообщения и вывод об ошибке пользователю в случае несоответствия стандартам. Рассматриваются методика испытания и тестирование программного обеспечения в случае передачи различных форматов сообщений. При работе программы с тестовыми данными получены подтверждающие результаты работы программы, и все результаты совпали с результатами ручной проверки Distributed networks are often used. Distributed networks also include wireless networks. Wireless networks are used to manage autonomous objects. The article discusses wireless communication network standards, including those for work in unmanned aerial vehicles, such as IEEE 802.11 and MAVLink standards, since wireless technologies for transmitting information are more widespread and used in various fields (telecommunications, smart home, technical monitoring, Internet of Things, unmanned technologies). The features and format of message transmission according to IEEE 802.11 and MAVLink network standards are discussed in detail. To research the IEEE 802.11 and MAVLink standards, a specialized software for validating these standards was developed, which ensures the sending of messages and decrypts them separately by fields. Validation of the correctness of all blocks of the transmitted message is carried out and an error message is output to the user in case of non-compliance with the standards. The article discusses the methodology of testing and testing software in the case of transmission of various message formats. When the program was working with test data, the confirming results of the program were obtained, and all the results coincided with the results of manual verification.

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Rudahindwa, Susan, Leon Mutesa, Eugene Rutembesa, Jean Mutabaruka, Annie Qu, Derek E. Wildman, Stefan Jansen, and Monica Uddin. "Transgenerational effects of the genocide against the Tutsi in Rwanda: A post-traumatic stress disorder symptom domain analysis." AAS Open Research 1 (January 14, 2020): 10. http://dx.doi.org/10.12688/aasopenres.12848.2.

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Background: A number of studies have investigated transgenerational effects of parental post-traumatic stress disorder (PTSD) and its repercussions for offspring. Few studies however, have looked at this issue in the African context. Methods: The present study addresses this gap by utilizing a Pearson correlation matrix to investigate symptom severity within the three Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD symptom domains in mothers exposed to the genocide against the Tutsi in Rwanda (n=25) and offspring (n=25), and an ethnically matched set of controls (n=50) who were outside of Rwanda during the 1994 genocide. All mothers were pregnant with the offspring included in the study during the time of the genocide. Results: Total PTS score was significantly (p<0.01) correlated with each of the three symptom domains at various strengths in both cases and controls. No significant differences in association of total PTS score and PTSD symptom domains were observed between exposed mothers and offspring, suggesting that each symptom domain contributed equivalently to both exposed mothers and offspring distress. In contrast, the re-experiencing symptom domain showed a significant difference in correlation to overall PTS score in non-exposed mothers compared to their offspring (p<0.05), with mothers showing a significantly higher correlation. Furthermore, the correlation between avoidance/numbing symptoms to overall PTS was significantly different (p≤0.01) across exposed and non-exposed mothers. As a secondary analysis, we explored the relationship between DNA methylation in the glucocorticoid receptor (NR3C1) locus, an important stress modulating gene, and PTSD symptom domains, finding an association between DNA methylation and re-experiencing among genocide-exposed mothers that exceeded any other observed associations by approximately two-fold. Conclusions: This is the first report, to our knowledge, of a symptom-based analysis of transgenerational transmission of PTSD in sub-Saharan Africa. These findings can be leveraged to inform further mechanistic and treatment research for PTSD.

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Nakphong, Michelle K., and Hiram Beltrán-Sánchez. "Socio-economic status and the double burden of malnutrition in Cambodia between 2000 and 2014: overweight mothers and stunted children." Public Health Nutrition 24, no. 7 (February 26, 2021): 1806–17. http://dx.doi.org/10.1017/s1368980021000689.

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AbstractObjective:The Cambodian population has experienced an increase in the proportion of stunted children who have overweight mothers during a period of rapid social and economic growth. We aimed to identify socio-economic factors associated with this household-level double burden over time.Design:We used data from four Cambodia Demographic and Health Surveys from 2000 to 2014 to study the impact of socio-economic status (SES) on the link between child stunting and overweight mothers in two periods 2000–2005 v. 2010–2014. We hypothesised that SES would be a primary factor associated with this phenomenon.Participants:We included 14 988 children under the age of 5 years, among non-pregnant mothers aged 15–49 years of age and conducted analysis on a subsample of 1572 children with overweight mothers.Setting:Nationally representative household survey across all regions.Results:SES factors, specifically household wealth and maternal employment in service or manual occupations (in 2010–2014), are the main drivers of stunting among children of overweight mothers. Children with overweight mothers in the poorest households are more than twice as likely to be stunted than in the richest in both periods (2000–2005: adjusted OR (aOR) = 2·53, 95 % CI: 1·25, 5·13; 2010–2014: aOR = 2·61, 95 % CI: 1·43, 4·77), adjusting for other SES factors, indicating that despite decreasing income inequality, the poorest continue to bear excess risk of a double burden of malnutrition. Maternal short stature also doubled the likelihood of child stunting in both periods, which suggests intergenerational transmission of adversity and physical underdevelopment.Conclusions:Socio-economic inequalities should be addressed to reduce disparities in the household-level double burden of malnutrition.

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Oktian, Yustus Eko, Sang-Gon Lee, and Byung-Gook Lee. "Blockchain-Based Continued Integrity Service for IoT Big Data Management: A Comprehensive Design." Electronics 9, no. 9 (September 3, 2020): 1434. http://dx.doi.org/10.3390/electronics9091434.

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The state-of-the-art centralized Internet of Things (IoT) data flow pipeline has started aging since it cannot cope with the vast number of newly connected IoT devices. As a result, the community begins the transition to a decentralized pipeline to encourage data and resource sharing. However, the move is not trivial. With many instances allocating data or service arbitrarily, how can we guarantee the correctness of IoT data or processes that other parties offer. Furthermore, in case of dispute, how can the IoT data assist in determining which party is guilty of faulty behavior. Finally, the number of Service Level Agreement (SLA) increases as the number of sharing grows. The problem then becomes how we can provide a natural SLA generation and verification that we can automate instead of going through a manual and tedious legalization process through a trusted third party. In this paper, we explore blockchain solutions to answer those issues and propose continued data integrity services for IoT big data management. Specifically, we design five integrity protocols across three phases of IoT operations—during the transmission of IoT data (data in transit), when we physically store the data in the database (data at rest), and at the time of data processing (data in process). In each phase, we first lay out our motivations and survey the related blockchain solutions from the literature. We then use curated papers from our surveys as building blocks in designing the protocol. Using our proposal, we augment the overall value of IoT data and commands, generated in the IoT system, as they are now tamper-proof, verifiable, non-repudiable, and more robust.

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Tan, Junxiang, Haojie Zhao, Ronghao Yang, Hua Liu, Shaoda Li, and Jianfei Liu. "An Entropy-Weighting Method for Efficient Power-Line Feature Evaluation and Extraction from LiDAR Point Clouds." Remote Sensing 13, no. 17 (August 30, 2021): 3446. http://dx.doi.org/10.3390/rs13173446.

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Power-line inspection is an important means to maintain the safety of power networks. Light detection and ranging (LiDAR) technology can provide high-precision 3D information about power corridors for automated power-line inspection, so there are more and more utility companies relying on LiDAR systems instead of traditional manual operation. However, it is still a challenge to automatically detect power lines with high precision. To achieve efficient and accurate power-line extraction, this paper proposes an algorithm using entropy-weighting feature evaluation (EWFE), which is different from the existing hierarchical-multiple-rule evaluation of many geometric features. Six significant features are selected (Height above Ground Surface (HGS), Vertical Range Ratio (VRR), Horizontal Angle (HA), Surface Variation (SV), Linearity (LI) and Curvature Change (CC)), and then the features are combined to construct a vector for quantitative evaluation. The feature weights are determined by an entropy-weighting method (EWM) to achieve optimal distribution. The point clouds are filtered out by the HGS feature, which possesses the highest entropy value, and a portion of non-power-line points can be removed without loss of power-line points. The power lines are extracted by evaluation of the other five features. To decrease the interference from pylon points, this paper analyzes performance in different pylon situations and performs an adaptive weight transformation. We evaluate the EWFE method using four datasets with different transmission voltage scales captured by a light unmanned aerial vehicle (UAV) LiDAR system and a mobile LiDAR system. Experimental results show that our method demonstrates efficient performance, while algorithm parameters remain consistent for the four datasets. The precision F value ranges from 98.4% to 99.7%, and the efficiency ranges from 0.9 million points/s to 5.2 million points/s.

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Rudahindwa, Susan, Léon Mutesa, Eugene Rutembesa, Jean Mutabaruka, Annie Qu, Derek E. Wildman, Stefan Jansen, and Monica Uddin. "Transgenerational effects of the genocide against the Tutsi in Rwanda: A post-traumatic stress disorder symptom domain analysis." AAS Open Research 1 (April 18, 2018): 10. http://dx.doi.org/10.12688/aasopenres.12848.1.

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Анотація:

Background: A number of studies have investigated transgenerational effects of parental post-traumatic stress disorder (PTSD) and its repercussions for offspring. Few studies however, have looked at this issue in the African context. Methods: The present study addresses this gap, utilizing confirmatory factor analysis (CFA), to investigate symptom severity within the three Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD symptom domains in mothers exposed to the genocide against the Tutsi in Rwanda (n=25) and offspring (n=25), and an ethnically matched control group of mothers (n=25) and offspring (n=25) who were outside of Rwanda during the genocide. All mothers were pregnant during the time of the genocide with the offspring included in the study. Missing data were excluded from the analyses. Results: We found that among the three symptom domains of PTSD, the re-experiencing symptom domain loaded most strongly onto PTSD among mothers directly exposed to the genocide (Beta = 0.95). In offspring of exposed mothers, however, the three symptom domains of PTSD yielded almost equal loading values (Beta range = 0.84-0.86). Conversely, among non-exposed mothers and their offspring, the hyperarousal symptom domain of PTSD loaded most strongly onto PTSD (Beta = 1.00, Beta = 0.94, respectively). As a secondary analysis, we also explored the relation between DNA methylation in the glucocorticoid receptor (NR3C1) locus, an important stress modulating gene, and individual PTSD symptom domains, finding a strong association between DNA methylation and re-experiencing among genocide-exposed mothers that exceeded any other observed associations by approximately two-fold. Conclusions: This is the first report, to our knowledge, of a symptom-based analysis of transgenerational transmission of PTSD in Africa. These findings can be leveraged to inform further mechanistic and treatment research for PTSD.

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Buchma, Ihor, and Mykhailo Voichenko. "Overview of methods and means of implementation of information and measuring components cyber-physical systems for electromagnetic probing." Technology audit and production reserves 3, no. 2(65) (June 30, 2022): 36–40. http://dx.doi.org/10.15587/2706-5448.2022.260245.

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The object of research is cyber-physical systems for the study of inhomogeneous environments, in particular, such as land and water depths, in order to find in them the leading bodies. One of the most problematic places in the creation of such systems is a highly sensitive meter of small phase shifts with a low sensitivity threshold. During the study, a review of methods for achieving a low threshold of sensitivity to phase shift. The main one is the method of converting the phase shift into the amplitude modulation coefficient. The implementation of the method is based on the sum-difference transformation with the preliminary introduction of the quadrature phase shift between the signals. The results concerning the methods of solving the following problems are obtained: – increasing the temperature stability of the quadrature phase shifter; – reducing the non-identity of the transmission coefficients of the sumo-difference scheme channels; – allocation of the amplitude of the amplitude-phase-modulated signal at low ratios of the frequencies of the input signals and switching. The first problem is partially solved by dividing the quadrature phase shifter into two equal halves, placed in different channels, with approximately the same phase temperature coefficients. The second problem is also solved by manual calibration before measurement. The most difficult task is to extract the bypass from the amplitude-phase-modulated signal, in which the carrier frequency is only several times greater than the bypass. The difficulty is that the detection produces combinational frequencies due to phase modulation. Therefore, it is difficult to separate them. Several methods of allocating the bypass, if the frequency of the input signals is fixed, are considered. This allows to get the sensitivity threshold(1·10–4÷3·10–5) of advice. Reducing the operating frequency of the signals increases the depth of research, but increases the impact of flicker noise. The minimum frequency is 10 Hz. Therefore, these methods are not suitable for frequencies of Hz units. Methods to reduce the impact of flicker noise will be considered in another paper.

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Ravichandran, Ramamoorthy, Bandana Barman, Tarani Mondal, Gopal Datta, and Ravi Kannan. "Cobalt radiation therapy treatments with opposed plain fields and beam flattening filter." International Journal of Radiology & Radiation Therapy 8, no. 4 (November 23, 2021): 179–81. http://dx.doi.org/10.15406/ijrrt.2021.08.00312.

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Low LET radiations such as cobalt (1.25 MeV) and 6 MV linac megavoltage gamma/x radiations continue to be a basic facility in a busy radiation therapy department. When the beam profiles in water are carefully scrutinized, linac beams have flattened isodose curves compared to slightly rounded curves in Co-60 beams at all depths. It was speculated that to overcome slight non-uniformity in the edges, as well as slight variations inside the planning target volume (PTV), a beam flattening filter may be preferable to be used along with plain radiotherapy fields. A pilot study of clinical use of beam flattener in cobalt beam is reported. A flattening filter (FF) was locally made out of dental wax, for 20 x 20cm field, in the 780E Telecobalt machine (M/s MDS Nordian, Canada). Beam profiles with and without FF were measured using water phantom, to confirm the filter efficiency. Both manual and Radiation Field (RFA) methods in water phantom confirmed efficacy of wax filter. This flattened beam was used in the treatments of Uterine Cervix and Oesophagus cancers, (25 patients each) with a measured filter transmission factor 0.805 in treatment plans. All the patients completed the prescribed dose of 50Gy in 25 fractions for Ca Cervix and 50Gy/25 fractions or 50.4Gy/28 fractions for Ca Oesophagus; at 5 fractions/ week treatment regimens. Case records of these patients retrospectively verified did not reveal any untoward associated morbidity on routine clinical follow ups during treatment or immediate follow up. As multi-leaf collimated cobalt beam also has built in rounded beam profiles, outcome of this work implemented in clinical applications add to new research knowledge. As cervix, head and neck, oesophagus malignancies form significant percentage of radiation oncology treatments, results of this present work will benefit many conventional treatments. It is strongly recommended that the clinical efficacy of FF Cobalt treatments be investigated in a controlled clinical trial, by random allotments with FF plain fields, with output corrections.

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Engelhardt, Christian, Jochen Witzig, Thomas Tobie, and Karsten Stahl. "Influence of water contamination in gear lubricants on wear and micro-pitting performance of case carburized gears." Industrial Lubrication and Tribology 69, no. 4 (July 10, 2017): 612–19. http://dx.doi.org/10.1108/ilt-07-2016-0152.

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Purpose Water can alter the performance of modern gear lubricants by influencing the flank load carrying capacity of gears significantly. The purpose of this paper is to investigate the influence of water contaminations in different kinds of base oils on the micro-pitting and wear performance of case carburized gears. Design/methodology/approach Concerning micro-pitting and wear, tests, based mostly on the following standardized tests, are performed on a Forschungsstelle fuer zahnraeder und getriebebau (FZG)-back-to-back gear test rig: micro-pitting short test Graufleckenkurztest (GFKT) according to DGMK 575 (screening test), micro-pitting test Graufleckentest (GT) according to FVA 54/7 (load stage test and endurance test) and Slow-speed wear test according to DGMK 377. To investigate the effect of water on the gear load carrying capacity dependent on different types of base oils, two polyglycol oils (PG1 and PG2), a polyalphaolefin oil, a mineral oil and an ester oil E are used. Each of these oils are common wind turbine gear oils with a viscosity ISO VG-220. Additionally, a manual transmission fluid with a viscosity of society of automotive engineers (SAE) 75W-85 is tested. Findings Considering the micro-pitting and wear performance, a significant decrease caused by water contaminations could not be detected. Regarding pitting damages, a generally negative influence was observed. This influence was differently distinctive for different base oil types. Especially non-polar lubricants seem to be affected negatively. The documented damages of the tooth flanks confirm this observation. While typical pitting damages appeared in test runs with polar lubricants, the disruption in test runs with non-polar lubricants was more extensive. Based on the experimental investigations, a general model of the damaging mechanisms of water contaminations in lubricants was derived. It is split into three partitions: interaction lubricant–water (effect of water on the molecular structure of base oils and additives), chemical-material-technological (especially corrosive reactions) and tribological influence (effect of water droplets in the contact zone). It has to be considered that the additive package of lubricants affects the influence of water contaminations on the flank load carrying capacity distinctively. An influence of water on the micro-pitting and wear performance in other than the given lubricants cannot be excluded. Originality/value While former research work was focused more on the effects of water in mineral oils, investigations concerning different types of base oils as well as different types of damages were carried out within this research project.

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SEREDA, Vladyslav A., Maya V. AMBROZHEVICH, and Aleksey V. KORNEV. "Method of Compact Ground Launching Devices Shape Formation for Unmanned Aerial Vehicles." Problems of Mechatronics Armament Aviation Safety Engineering 13, no. 1 (March 31, 2022): 9–26. http://dx.doi.org/10.5604/01.3001.0015.8101.

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The purpose of this paper is to develop a method for forming the shape of compact ground launching devices (GLDs) unmanned aerial vehicles (UAVs), which includes three stages. Firstly, the choice on the basis of the theory of dimension and similarity of the closest analogue of the design object based on world experience gained in this field. Secondly, the creation of a comprehensive model of the working process of GLD and a universal method for its numerical implementation. Thirdly, the solution to the problem of optimizing the dynamic characteristics of GLD. At the described stages of the formation of the shape of an GLD UAV, a statistical analysis of the technical perfection of known analogues of UAV launch systems, methods of the theory of similarity and dimension in mechanics, methods of numerical simulation of the working process, and also methods of conditional parametric optimization are used. The undoubted importance of the problem of the equivalent development of the components of the UAS, consisting of an aircraft and a launch system (catapult). The traditionally non-priority status of GLD in the general cycle of the complex design program is also known. A systematic solution to this problem lies in the mainstream of creating common approaches, one of which is contained in this article. The proposed method of forming the appearance of compact GLDs UAV can be extended to a wide class of starting systems containing a thermal expansion machine and a mechanical component. In the presented form, the method is not applicable to systems of air, aerodrome and manual launch of UAVs. A method has been developed for the formation of the shape of GLD based on the energy relations of the criterion type between useful functions and the corresponding costs, with subsequent verification numerical studies of the launch processes based on specially created technology of a computational experiment, as well as optimization of the dynamic characteristics of GLD. The method of forming the shape of compact GLD is universally applicable to any type of catapults, regardless of the type of transmission and drive, since many particular forms of organization of the working process are generalized using the criteria of energy perfection, a comprehensive physical and mathematical model and normalization of the starting overload.

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Köllmann, Katharina, Yanchao Zhang, Nicole Wente, Anneke Lücken, Stefanie Leimbach, and Volker Krömker. "Effects of Suckling on the Udder Health of Foster Cows." Ruminants 1, no. 2 (October 9, 2021): 100–117. http://dx.doi.org/10.3390/ruminants1020008.

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In a foster cow system, one or more calves are reared by a foster cow. With regard to the growing rejection towards the early separation of cow and calf after calving, such alternative rearing methods with prolonged cow–calf contact are coming more into focus. Nevertheless, there is a lack of recent studies investigating the effects of suckling multiple calves on the udder health of a foster cow. The present study aimed to initially describe the status and development of the udder condition and the microbial colonisation during the foster period. Thereby, the objectives were to determine whether suckling multiple calves was associated with an increase in intramammary infections (IMI) and a deterioration of udder constitution. A total of 99 Holstein Friesian foster cows from a large organic dairy farm in eastern Germany were included in this pilot study. Each foster cow was suckled by 3–4 calves and not additionally milked. Quarter milk samples were taken for cytomicrobiological examination at the beginning and end of the approximately 3.5 months suckling period. At the same time, the udders of 91 of these foster cows were clinically examined by visual assessment and manual palpation. In both the first and second examination (E1 and E2, respectively), Corynebacterium ssp. and non-aureus staphylococci (NaS) constituted the most frequently detected pathogen species in the 385 examined udder quarters. Classifying the quarters into mastitis categories was significantly different between the two examinations (p = 0.001). The number of quarters considered as healthy increased from E1 to E2 by 8.5%. At the same time, the number of quarters with mastitis decreased by 2.6%, the number of quarters with non-specific mastitis by 11.4% and the number of quarters with a latent infection increased by 5.4%. In total, 69.4% of the 121 infected udder quarters in E1 were bacteriologically cured in E2. A cytological cure was achieved in 28.1% of the 385 quarters. Both the bacteriological and cytological cure rate were spontaneous. A new infection occurred in 23.1% of the 385 examined udder quarters and was mainly attributable to infections with Corynebacterium spp. and NaS. During the suckling period, mainly new infections occurred and amounted to 73% in relation to presumed persistent infections (18.9%). The new infections were mainly attributable to infections with Corynebacterium spp. and NaS. Pasteurella spp. were also found in high percentages. A total of 10.1% of the quarters showed an increase in somatic cell count (SCC) above the threshold of 100,000 cells/mL from E1 to E2, indicating a new subclinical mastitis. Regarding udder condition, significant changes during the foster period were an increase in udder skin and teat lesions, a decrease in udder oedema, an increased amount of udder quarters with a consistency considered as normal and an increase in the number of udders showing no sign of udder cleft dermatitis. Moreover, teat length, circumference, and diameter increased significantly (p < 0.05). In conclusion, there is a possibility that suckling multiple calves improves udder health in terms of mastitis but leads to an increased pathogen transmission at the same time, resulting in an increase in latent infections. Additionally, pathogens as Pasteurella spp., which are usually located in the upper respiratory system, could be detected in the mammary gland. The changes concerning the udder condition were manifold. However, it has not yet been conclusively clarified whether all these changes are exclusively due to calf suckling. Further investigations with a non-suckled control group are required.

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Seet, Meei Jiun, Sohinee Bhattacharya, and Ashalatha Shetty. "Maternal and Perinatal Outcomes in women with Hepatitis B Carrier State." Women Health Care and Issues 2, no. 1 (March 22, 2019): 01–04. http://dx.doi.org/10.31579/2642-9756/005.

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Introduction Hepatitis B is the most common form of viral hepatitis. Much has been done for the prevention of Hepatitis B transmission from mother to child. However, there is still very limited evidence looking at maternal obstetrics and perinatal outcomes, such as gestational diabetes, antepartum haemorrhage and preterm labour, hypertensive disorders in pregnancy and small for gestational age, with Hepatitis B infected women. These adverse pregnancy outcomes, if significant, may affect future antenatal care and have a negative impact on public health. This study aims to determine the association between these adverse pregnancy and neonatal outcomes with maternal Hepatitis B carrier state. Methods This is a retrospective cohort study comparing adverse pregnancy and neonatal outcomes in primigravid women who delivered singleton babies after 24 completed weeks of gestation and are carrier for Hepatitis B virus with those who are non-carrier for Hepatitis B virus, between 1992 and 2013 in Aberdeen Maternity Hospital. The adverse pregnancy and neonatal outcomes studied include hypertensive disorders in pregnancy, antepartum haemorrhage, preterm birth <37 weeks, induction of labour, caesarean delivery, low birth weight and admission to neonatal unit. Data was extracted from the Aberdeen Maternity and Neonatal Databank (AMND), which was established in 1950 to record all pregnancy-related events occurring in Aberdeen city and district in the northeast of Scotland. Statistical analysis was done with SPSS version 21 using independent samples t-test for normally distributed continuous variables and chi-squared test for categorical variables. Multivariate logistic regression analysis using a multilevel random effects regression model was also conducted to adjust for confounding factors. Results The data set contained a sample size of 35116 primigravid women with singleton pregnancies, with 59 being carrier for Hepatitis B virus (represented by positive HBsAg status). HBsAg-positive women had significantly lower mean Body Mass Index and were more likely to be from the manual social class (registrar general’s occupation-based social class). On unadjusted analysis, there were no significant differences in the prevalence of all maternal and perinatal outcomes in both groups. However, after adjusting for confounding factors, HBsAg-positive women were more likely to have smaller babies (aOR 4.28; 95% CI 1.57-11.66). Conclusion Our study suggested higher frequencies of low birth weight babies in women with hepatitis B infection. We found no statistically significant differences in other adverse pregnancy and perinatal outcomes. As current evidence still shows inconsistent results, further research evaluating the possible effects of Hepatitis B viraemia on pregnancy outcomes is justified.

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Oliveira, A. P., R. C. Leite, M. B. Heinmam, L. G. B. Siqueira, A. Maciel, and J. H. M. Viana. "156 INVESTIGATION OF BOVINE HERPESVIRUS IN CUMULUS - OOCYTE COMPLEXES AND FOLLICULAR FLUID." Reproduction, Fertility and Development 20, no. 1 (2008): 158. http://dx.doi.org/10.1071/rdv20n1ab156.

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The world market for bovine embryos has increased in the past few years. However, sanitary problems such as foot and mouth disease in Brazil, vesicular stomatitis in South America, and bovine spongiform encephalopathy (BSE) in North America and Europe have increased concerns regarding the risk of introducing exotic diseases and/or more virulent serotypes of endemic diseases by embryo transfer. Many countries are trying to develop and/or improve new techniques for infectious disease detection, with the scientific basis to support the import and export of animal germplasm. Therefore, the epidemiology of the diseases and the interaction between pathogens and cumulus–oocyte complexes (COCs), embryos, and semen must be investigated. Despite the many studies that have been carried out to evaluate the possibility of transmission of infectious agents by the embryo, few data are available regarding COC susceptibility (Tsuboi et al. 1992 J. Vet. Med. Sci. 54, 1179–1181). The aim of this study was to evaluate the presence of bovine herpes virus serotype 1 (BHV-1) in COCs and follicular fluid (FF) collected from naturally infected animals in a low stress condition. Blood samples of non-lactating Gyr breed (Bos indicus) cows were collected and evaluated for BHV-1 antibodies by the serum neutralization microplate test, performed as described in the Manual for Standards for Diagnostic Tests and Vaccines (OIE, 1992). The cows were diagnosed as serologically positive (n = 38) or serologically negative (n = 8), and kept under grazing in Brachiaria decumbens pasture with mineral supplementation. The cows considered as positive showed titers greater than 1/4. COCs and follicular fluid (FF) were obtained by ovum pick-up (OPU) using sterile and disposable materials for each animal. Virus detection was performed by the PCR technique. PCR sensitivity was made using COCs and FF recovered from eight BHV-1 serologically negative animals. These samples were either artificially infected on plates with 106.5 TCID in 50 µL of IBR Colorado 1 reference serotype (ATCC, VR-864) or used as a negative control. The PCR analitical sensitivity was 100.5 TCID. The presence of BHV-1 in COCs and FF was not detected in any of the animals, despite the high sensitivity of the PCR technique. In the present in vivo model, results show that COCs collected from serologically BHV-1 positive cows presenting no clinical signs of the illness and managed in a low stress condition could be used as donors for in vitro fertilization procedures with minimal sanitary risks. Also, the absence of the virus in COCs and FF cannot be used as a predictor of BHV-1 infection status in bovine herds.

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Vaz, Talita Pereira, Marcella Oliveira Gama-Melo, Patrícia Flávia Quaresma, Célia Maria Ferreira Gontijo, Gilmar Santos, Fernando Sérgio Barbosa, and Gilberto Fontes. "Evaluation of the euthanasia of seropositive dogs for canine visceral leishmaniasis as the only method of controling the disease in the enzootic area in the Midwestern Minas Gerais." Pesquisa Veterinária Brasileira 40, no. 2 (February 2020): 107–12. http://dx.doi.org/10.1590/1678-5150-pvb-6165.

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ABSTRACT: Human Visceral Leishmaniasis (VL) is expanding, and it is distributed in the five geographic regions of Brazil, with the Northeast being the region that presents the most significant number of registered cases. The main urban reservoir of the etiological agent of VL is the domestic dog, and it is known that canine cases precede human cases. One of the control actions of VL, recommended by the Ministry of Health, is performing the euthanasia of seropositive dogs. In 2013, in the municipality of Iguatama/MG, the first canine serological survey was carried out in the city, with a prevalence of 8.3% of seropositive dogs for Leishmania infantum. Of the seropositive animals for Canine Visceral Leishmaniasis (CVL) in this survey, 84% were euthanized, and 16% died within two years after diagnosis. No other control measures for CVL were taken in the municipality. The objectives of the present study were to determine the current prevalence of seropositive dogs for CVL in the municipality of Iguatama and to observe the impact of euthanasia of seropositive dogs to VL as the only control measure performed in this municipality, which is considered an enzootic area of the disease. For this, a new canine epidemiological survey was carried out in the municipality of Iguatama, following the guidelines of the Manual of Surveillance and Control of Visceral Leishmaniasis. Blood samples were collected from 270 dogs and tested by DPP® immunochromatographic test and by Enzyme-Linked Immunosorbent Assay (ELISA). The animals that presented inconclusive results had new blood samples collected and analyzed. The only animal that showed a positive result in DPP® and undetermined in the ELISA, in the first evaluation, became seropositive four months later, so this study reinforces the recommendation of the Ministry of Health to reassess dogs that present inconclusive results for CVL. From a total of 270 samples, 21 (7.8%) were reagents in both tests. Thus, the prevalence of seropositive dogs for CVL, in 2017, in the urban area of the municipality of Iguatama was 7.8%. The Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) molecular technique confirmed infection by L. infantum in the ten dogs sampled with CVL-positive serology. The comparison between the current prevalence (after euthanasia) with that found in 2013 (8.3%), there was no significant difference (p=0.764). The prevalence of CVL in the urban area of the municipality of Iguatama is still high, making it possible to presume that the euthanasia of seropositive dogs for CVL, and the absence of monitoring or other interventions measures, did not contribute to decrease the transmission of the parasite and was not sufficient for the control of CVL in the municipality of Iguatama, an area considered as non-endemic to CVL until 2013.

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Edwards, Donna, Elizabeth Sierra Potchanant, Xinxin Huang, Zejin Sun, Maegan Capitano, Caroline Miller, Ying He, Hal E. Broxmeyer, and Grzegorz Nalepa. "Patient-Tailored Mouse Genome Editing Recapitulates Hematopoietic and Systemic Manifestations of Barth Syndrome." Blood 130, Suppl_1 (December 7, 2017): 775. http://dx.doi.org/10.1182/blood.v130.suppl_1.775.775.

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Abstract Barth syndrome (BTHS; OMIM# 302060) is an X-linked disorder of neutropenia, cardiomyopathy and muscular weakness due to mitochondrial dysfunction secondary to inherited tafazzin (TAZ) mutations. Neutropenia occurs in the majority of BTHS patients, leading to high risk of recurrent life-threatening bacterial infections. The etiology of the G-CSF-responsive neutropenia in BTHS is incompletely understood and appears to reflect impaired granulopoiesis. Long-term risk of myelodysplasia (MDS) in BTHS individuals requiring chronic G-CSF therapy is unknown due to the rarity of the disorder; further, genotype-phenotype correlations between the severity of neutropenia and TAZ mutations remain to be elucidated. Genetic Taz knockout is embryonic lethal in the mouse. Therefore, a genetic BTHS mouse model is urgently needed to improve our mechanistic understanding of this disease and develop clinical studies based on preclinical evidence. We employed CRISPR/Cas system to edit our BTHS patient's tafazzin point mutation (D75H) into the endogenous murine Taz gene. The resulting mice recapitulated hematopoietic and systemic manifestations of Barth syndrome. TazD75H males are born at less than expected Mendelian frequencies (p<0.0001) and suffer from perinatal lethality and failure to thrive with 69% decrease of body size at postnatal day 29 compared to age-matched wt males (p<0.0001). TazD75H males have neutropenia at 1 month of age evidenced by complete blood counts and independent manual peripheral smear analysis (p=0.04). Young TazD75H mice had mildly decreased bone marrow cellularity per femur (p=0.01675) accompanied by deficient functional bone marrow colony-forming ability compared to age- and sex-matched wt mice (approximately 3.5-fold decrease in CFU-GM, p=0.0002, and CFU-GEMM, p=0.0041), consistent with a functional hematopoietic defect. Similar to BTHS patients, TazD75H mice develop prenatal cardiomyopathy, with echocardiograms of surviving mice demonstrating left ventricular non-compaction (p=0.0339) and decreased ejection fraction (p=0.038). Further, TazD75H mice recapitulate the Barth syndrome phenotype of impaired skeletal muscle strength as shown by decreased ability to lift weights and perform hanging exercise (p=0.0072). Interestingly, TazD75H males developed infertility due to profound spermatogenesis arrest (p<0.0001). These data indicate that TazD75H mice recapitulate all crucial clinical findings in Barth syndrome. Given the role of tafazzin in mitochondrial cardiolipin metabolism, we examined the structure and function of mitochondria in TazD75H mice. Strikingly, transmission electron microscopy revealed accumulation of swollen mitochondria with fractured cristae in TazD75H hematopoietic cells, cardiomyocytes and skeletal muscle, reflecting the mitochondrial phenotype of BTHS patients. Total mitochondrial mass quantified by MitoTracker flow was unchanged in TazD75H hematopoietic cells, but flow cytometry using the JC-1 mitochondrial membrane potential probe revealed disrupted mitochondrial potential during live TazD75H hematopoiesis in multi-potential progenitors (MPPs, p=0.0025), Lin- Sca-1+ c-kit+ cells (p<0.0001), Lin- Sca-1- c-kit- (p=0.0036), lineage-negative (p<0.0001) and lineage-positive (p=0.0211) hematopoietic cells. Quantitative Seahorse metabolic profiling revealed impaired mitochondrial respiration in live TazD75H hematopoietic cells, confirming functional mitochondrial deficiency. In summary, our work demonstrates that impaired hematopoiesis in Barth syndrome, which is embryonic lethal in the mouse, can be recapitulated in vivo through editing a patient-specific hypomorphic tafazzin mutation into the murine genome. The precision-medicine TazD75H mouse model recapitulates clinical hallmarks of BTHS in hematopoietic and non-hematopoietic tissues, accompanied by structural and functional mitochondrial defects. This work enables in vivo studies to enhance our mechanistic understanding and treatment of hematopoetic and other defects in Barth syndrome. Figure Figure. Disclosures No relevant conflicts of interest to declare.

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Grant, Alex, and Colm O'Dwyer. "Thickness-Based Dispersion in Opal Photonic Crystals." ECS Meeting Abstracts MA2022-02, no. 36 (October 9, 2022): 1304. http://dx.doi.org/10.1149/ma2022-02361304mtgabs.

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Photonic crystals (PhCs) are types of colloidal crystals which demonstrate a host of exciting optical phenomena, the nature of which can lend insight into their structure and enable a range of potential applications in fields such as optics and optoelectronics,1 energy storage,2-6 and sensors for environmental monitoring, biomedicine and food preservation.7 Artificial opals8 are PhCs which can be formed easily using low-cost self-assembly methods and their structures are composed of highly ordered, close-packed, polymeric sphere arrays. While the optical behaviour of opals has received significant attention over the last number of decades, there is limited information on the effect of crystal thickness on the optical properties they display. Most studies focus their attention on the lattice parameters and refractive index contrast within the materials.9,10 Here, the relationship between volume fraction and crystal thickness using an evaporation-induced self-assembly (EISA) method of formation is established.11-13 The extent to which thickness can be used to manipulate the optical properties of the crystals is explored, focusing on the change in the photonic band gap (PBG). Specifically, the thickness-induced changes in the properties which define the PBG for a range of volume fractions. Through meticulous structural and optical characterization, primarily in the form of scanning electron microscopy (SEM) images and angle-resolved ultraviolet-visible (UV-Vis) spectroscopy, the quality of the crystals formed is examined, with thicknesses exceeding 40 layers grown from volume fractions below 0.15 %, for the first time, to our knowledge. Crystal structure is correlated to optical fingerprint, shown in the form of transmission spectra in the UV-Vis region. We expect this work to provide our colleagues in the scientific community with a direct correlation between crystal thickness and the optical fingerprint of opal PhCs. Our analysis also stands as a manual to aid any future attempts at the growth of ultra-thick colloidal crystals. Such research may act as a precursor to further developments in materials employed in the photonics, sensing, energy storage and related communities. References 1 M. I. Shalaev, W. Walasik, A. Tsukernik, Y. Xu, and N. M. Litchinitser, Nature Nanotechnology 14, 31 (2019). 2 D. McNulty, A. Lonergan, S. O'Hanlon, and C. O'Dwyer, Solid State Ionics 314, 195 (2018). 3 D. McNulty, H. Geaney, D. Buckley, and C. O'Dwyer, Nano Energy 43, 11 (2018). 4 D. McNulty, E. Carroll, and C. O'Dwyer, Advanced Energy Materials 7, 1602291 (2017). 5 E. Armstrong, D. McNulty, H. Geaney, and C. O’Dwyer, ACS Applied Materials & Interfaces 7, 27006 (2015). 6 D. McNulty, H. Geaney, Q. Ramasse, and C. O'Dwyer, Adv. Funct. Mater. 30, 2005073 (2020). 7 J. Hou, M. Li, and Y. Song, Nano Today 22, 132 (2018). 8 E. Armstrong and C. O'Dwyer, Journal of Materials Chemistry C 3, 6109 (2015). 9 D. R. Solli and J. M. Hickmann, Optical Materials 33, 523 (2011). 10 S. G. Romanov, Physics of the Solid State 59, 1356 (2017). 11 Q. Jiang, C. Li, S. Shi, D. Zhao, L. Xiong, H. Wei, and L. Yi, Journal of Non-Crystalline Solids 358, 1611 (2012). 12 J. Zhang, Y. Li, X. Zhang, and B. Yang, Advanced Materials 22, 4249 (2010). 13 A. Lonergan, C. Hu, and C. O'Dwyer, Phys. Rev. Materials 4, 065201 (2020). 14 S. O'Hanon, D. McNulty, R. Tian, J. Coleman, and C. O'Dwyer, J. Electrochem. Soc. 167, 140532 (2020). Figure 1. Optical and structural analysis for 350 nm PS opals formed by EISA. Analysis presented in the form of transmission spectra obtained for samples formed from a range of five volume fractions, labelled by their dilution factors (a,d,g), sample plan view SEM images (b,e,f), and sample cross-sectional SEM images (c,f,i). (a-c) correspond to regions of maximum opal thickness, (d-f) to regions of lesser thickness, (g-i) to regions of minimal thickness. Figure 1

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F., Minaya Muñoz, Valera Garrido F., Pereira Barbosa M., and Espinola Marcos A. "Ultrasound assessment of the myofascial trigger point, where is the local twitch response located?" Revista Fisioterapia Invasiva / Journal of Invasive Techniques in Physical Therapy 02, no. 02 (December 2019): 119–20. http://dx.doi.org/10.1055/s-0039-3402500.

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Background A myofascial trigger point (MTrP) is defined as a nodule or hyperirritable spot of focal pain in response to pressure which is found on a palpable taut band of skeletal muscle. For the physical therapy diagnosis, assessment tools such as musculoskeletal ultrasound have shown that it is possible to visualize the MTrP in gray scale (B mode) and in elastography; however, no previous studies have evaluated the correlation between the appearance of a local twitch response and the presence of a myoaponeurotic septum. The aim of the present study was to evaluate the correlation between the local twitch response and the presence of a myoaponeurotic septum at the time of the response. Material and Methods A prospective observational study was performed at the Sannus Clinic center (Madrid) including patients with the following inclusion criteria: subjects over the age of 18, with the presence of active MTrPS according to the criteria established by Travell & Simons. The ultrasound-guided dry needling technique was performed (US-guided DN) on the dysfunctional muscles, according to the methods described by Valera & Minaya, as follows: 1) manual identification and localization of the myofascial trigger point; 2) Ultrasound assessment of the area corresponding to the identified MTrP. The palpatory hand was substituted in this case by the ultrasound probe which applies pressure upon this band, for its study; 3) Establishment of safety measures during the procedure; 4) The extremes of the probe were marked using a dermographic pen; 5) Removal of the probe and asepsis of the skin of the area prior to needling; 6) Pre-intervention measures: hand-washing, use of non-sterile gloves and a probe cover, followed by preparation of the sterile needle and gauze; 7) The probe was placed on the area of study, with the marks established on the skin; 8) Ultrasound-guided intervention; 9) Needle removal and compression during 30 seconds; 9) Re-assessment. Once the local twitch response was visualized, the position of the needle tip was marked on the ultrasound image. Results The sample was comprised of 40 patients (23 men; 17 women) who received the US-guided DN procedure in the following muscles: upper trapezius (n = 32), extensor digitorum (n = 25), infraspinatus (n = 14), medial gastrocnemius (n = 8), gluteus medius (n = 12). In 87.9% of muscles (n = 80) a local twitch response was obtained when the needle tip was close to the myoaponeurotic septum. Discussion From our point of view, the myoaponeurotic septum of a muscle with an active MTrP could represent a place for load transmission, which would justify the activation of the muscle tissue, and the genesis of the MTrP. Considering the diagnostic criteria of the MTrP, the local twitch response is one of the most determinant elements, therefore, its location in the proximity of this anatomical area could be used as a reference. Conclusions The local twitch response is often obtained in the proximity of a myoaponeurotic septum of the dysfunctional muscle.

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Watanabe, Yoshio. "Two kinds of feng-shui history in Japan: science and divination." Estudos Japoneses, no. 35 (March 7, 2015): 124–38. http://dx.doi.org/10.11606/issn.2447-7125.v0i35p124-138.

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In this paper, I don’tuse the word of “geomancy” but use “feng-shui”, as meaning a set of method and concept for an assessment for environmental impact against human life. Environmental impact assessment, connected with the feng-shui theory of later eras, first began with xiang-zhai (house and community observation), which appeared in the Zhou Period (770~256 BC.), Spring and Autumn/Warring States Periods(770~221 BC.) in China. Now I recognize the meanings of feng-shuiare indicated two kinds. One meaning is a kind of scientific thought through the ancient environmental impact assessment, and another meaning is a method of divination through judgments fortune-telling items. So I will mention about the Japanese history of feng-shuidivided into two kinds of histories. A number of scholars have pointed out the transmission of feng-shui knowledge to Japan, as recorded in the section of the Nihon Shoki (the Book of the ancient Japanese record) which reads: “In 601 AD, a buddhist monk named Kanroku arrived from Paekche (one of the country, ancient Korea) to Japan. As tribute, they brought books of astronomy and geography (same meaning of feng-shui)...”. After this record, terms synonymous with feng-shui can be sporadically seen in the records of ancient Japan. Continuing, in the Book of Ryo-no-gige (chapter of staff inst- ructions) of the 9th century in Japan, it states that 6 yin-yang practitioners of the yin-yang Bureau (Ministry of astronomical and geographical observations) “shall be in charge of divination sticks and souchi (feng-shui)”. Thus, one of the duties of the yin-yang practitioners was souchi. This was a form of divination and observation topography which was a predecessor of the feng-shui theory. Much later in time, we arrive at the Edo Period (1603~1868 AD.). In Wakan-sansai-zue, or Sino-Japanese encyclopaedia from this Period written by Terashima Ryoan, the compass (which developed later) was called a tokei-shin, and it is explained as “an instrument for determining directions and telling time”. According to Terashima Ryoan, it is a compass, like that used in Japan today for kasou (i.e. divining the fortune of a house from its directions and situation). The tokei-shin described by Terashima Ryoan was a “compass for sea navigation” developed further for sea navigation after the invention of the luo-pan (compass) in the Sung Period in China. This “compass for sea navigation” was a simplified version of the luo-pan for land divination (feng-shui), and until very recently, was used as a compass for small boats in Japan. After the luo-pan using a magnetic needle was invented, there is a history in China of using the luo-pan as a surveying instrument, i.e. as a successor of the previous tugui method based on sun shadow measurement. This was not a luo-pan notched with many graduations; rather, it was a luo-pan which attempted to measure accurate directions and angles by using only one type of graduation. This type of luo-pan was also used in Japan in the Edo Period called “banshin- raban”. In the Edo Period, there was active development of mines, and it was necessary to measure accurate bearings and angles for tasks like excavating mine tunnels. In the some of ancient Japanese written historical records, the synonymous words of “Chiri” (in Japanese), or “Dili” (in Chinese) could be recognized as the “geography” which has been used in ancient China. But we know two letters of “feng (wind) and shui (water)” that are widely used today all over the world. When it comes to the Edo period, the name “fuu-sui”, or “geography=Chiri” can be discovered at the time of feng-shui manual named “Kasou-sho”. A book of “Kasou-zukai or feng-shui illustration published in 1798 is commentary various divination ways in the name of “fuu-sui”. Since then, also in many other Edo periods, at the Kasou-sho manual, words and examples of “fuu-sui” are abundantly found, the knowledge of “fuu-sui” as a method of divination had been introduced to Japan. Currently, examples of I know the oldest word of “fuu-sui or feng-shui” in Japan is in a memorial document of “Engaku temple” in the Muromachi era. But I don’t know now that from Muromachi to Edo era, the term of “fuu-sui” has first used in Japan or not. Appeared in a “topography of Youshuu” in the Edo era and “Engaku temple document” in the Muromachi era, “fuu-sui or feng-shui” do not mean the knowledge of “geography” associated with land observations, but means a method how to judge right and wrong about their environmental conditions. We therefore, can recognize about the meaning of “Chiri” that there were two kinds or more of knowledge in Edo era. A Japanese geographer in Edo era named Nyoken Nishikawa wrote his book (1712). His book tells us an example of meaning of “Chiri”. Nyoken Nishikawa said that ranging from one of the house to the entire earth, “Chiri or geography” have various levels of meaning. “Fuu-sui” means “geographical conditions” themselves. There are good or bad conditions in “Chiri” itself, but not exist in human environmental judgments. “Geography” itself means environmental conditions, so there was no need to judge human environment good or bad. However, in the medieval period, Yin-yang diviner or fuu-sui master in Japan had broken out over wide area and using the name of “Chiri or geography”, explaining about the vicissitudes of descendant life, as a result of their adverse effects do not converge till now. At the time of Japan, there were many Yin-yang diviners preached weal or woe of human life for the common people. As the time passed, they were gradually increasing and Kasou-sho were also gradually increasing. Today in Japan and East Asia, we can take many books of feng-shui judgment and Kasou documents in our hand. These are filled with bothersome non-scientific judgment items. And because there are many different items in each feng-shui manuals, of course these books are fortune-telling books, but we can also find “some vestiges of scientific thought” in such feng-shui fortune-telling judgment items. European awareness about the declination was the end of 14th century, that is to say several hundred years later for China. Chinese direction finding methods and land surveying technology and knowledge, whose development was motivated by feng-shui divination and observation, subsequently spread to Europe (12th century) and Arabia (13th century). Therefore, today we must take another look at feng-shui research, on a global scale.

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Subodha Kumar, Rai G., Nagesha Parvathi, Rangegowda Suresh, Niruvappa Vinay, and Ittigi Vivekananda. "Efficacy and safety of povidone iodine with dimethyl sulfoxide vs 0.05% tretinoin in treatment of molluscum contagiosum: A randomized case control study." Our Dermatology Online 12, e (August 28, 2021): e63-e63. http://dx.doi.org/10.7241/ourd.2021e.63.

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ABSTRACT Background: MC is an infection caused by a poxvirus. It is a self limiting condition, active therapy needed to prevent further spread, relieve symptoms, to prevent scarring and for cosmetic and social reasons. Methods: 40 patients were randomly divided into 2 groups; 20 each for Povidone Iodine with DMSO and 0.05% Tretinoin cream. The given medication was applied at bed time over molluscum lesions. The assessment of response and side effects were performed weekly for 4 weeks. Results: At the end of 4 weeks, the mean lesion count decreased from 6.45±3.60 SD to 4.25±3.76 SD and from 6.85±4.08 SD to 3.60±4.76 SD in patients treated with Povidone Iodine and 0.05% Tretinoin cream respectively. Conclusion: Tretinoin showed fast recovery, lesions were resolved before 4 weeks. In Povidone Iodine with DOMS showed delayed response and even some of lesion extended beyond 4 weeks but the side effect were less. Key words: MC-molluscum contagiosum.DMSO-dimethyl sulfoxide; SD-standard INTRODUCTION Molluscum contagiosum is an infection caused by a poxvirus (molluscum contagiosum virus). It is self-limited infectious dermatosis, frequent in paediatric population, sexually active adults, and immunocompromised individuals. It is caused by molluscum contagiosum virus (MCV) which is a virus of the Poxviridae family. MCV is transmitted mainly by direct contact with infected skin, which can be sexual, non-sexual, or autoinoculation [1].The lesions, known as Mollusca, are small, raised, dome shaped and usually pearly white, pink, or flesh-coloured with a dimple or pit in the centre. They often have a pearly appearance. They’re usually smooth and firm. In most people, the lesions range from about the size of a pinhead to as large as 2 to 5 millimetres in diameter. They may become itchy, sore, red, and/or swollen [2]. Mollusca may occur anywhere on the body including the face, neck, arms, legs, abdomen, and genital area, alone or in groups. The lesions are rarely found on the palms of the hands or the soles of the feet. The disease is common, with an estimated prevalence of 5–11%. The disease is rare under the age of 1 year, perhaps due to maternally transmitted immunity and a long incubation period. In hot countries where children are lightly dressed and in close contact with one another, spread within households is not uncommon. The age of peak incidence is reported as between 2 and 5 years. In cooler climates, however, spread within households is rare and infection may occur at a later age, perhaps correlated with the use of swimming pools and shared bathing facilities. A later incidence peak in young adults is attributable to sexual transmission with lesions more common in the genital area [2]. Treatment modalities that have been tried are caustic destruction by cantharidin, trichloroacetic acid, diluted liquefied phenol, Irritants like salicylic acid, adapalene, nitric oxide cream, potassium hydroxide, benzoyl peroxide, lemon myrtle oil, tea tree oil, Surgical irritation like cryotherapy, laser. Immunological modality like diphencyprone, imiquimod, interferon, cimetidine, intralesional immunotherapy and Surgical removal. All-trans-retinoic acid (tretinoin) is easily available as cream base thought to involve the induction of local irritation which damages the viral protein-lipid membrane [2]. Povidone iodine is used primarily in Dermatology as a surgical preparation, as it has been recognized as a broad-spectrum, resistance-free biocidal agent for many years. Povidone iodine also has a long track record of safety and tolerability given its extensive history of use in the operating room. Although incompletely understood, it is likely that free iodine poisons electron transport, inhibits cellular respiration, destabilizes membranes, inhibits protein synthesis, and denatures nucleic acids. Although Povidone iodine kills micro-organisms including bacteria, viruses, yeasts, molds, fungi, and protozoa, it has scarcely been used for purposes outside of skin asepsis in Dermatology. DMSO is currently FDA approved for the treatment of interstitial cystitis. DMSO is also a very effective pharmaceutical vehicle, greatly enhancing percutaneous penetration when used in combination with other substances [3]. Although it is a self limiting condition, a decision may be made in favor of active therapy to prevent further spread, relieve symptoms, to prevent scarring and for cosmetic and social reasons. The current treatment modalities include physical destruction of the lesion by curettage, cryosurgery or manual expression and topical application of caustic agents such as trichloroacetic acid, cantharidin, silver nitrate etc [4]. These therapeutic approaches have to be undertaken in a hospital setup and are not well tolerated by children owing to substantial pain and fear. In addition, these can also result in scarring and abscess formation [5]. Topical application of povidine iodine solution and 0.05% Tretinoin cream are two relatively painless modalities that have been used. Although tretinoin 0.05% cream which is commonly used, have shown different efficacy and safety profile in different studies, there are very few studies using povidone iodine and comparing the two. Hence this study was undertaken in view of comparing the safety and efficacy of the above two modalities in treating molluscum contagiosum. MATERIALS AND METHODS Double blinded randomized control study was conducted among 40 patients who attended Out Patient Department (OPD) of Dermatology Venereology and Leprosy Department, Hassan Institute of Medical Sciences Hassan, during the period of august 2019 to January 2020. Patients with Molluscum contagiosum more than 1 year of age and not taken any treatment for past 3 months were included in the study. Pregnant, lactating women, patients with more than 25 lesions, patients with lesion involving eyelid, patients with secondary infection and those who have history of hypersensitivity to Povidine iodine or Tretinoin were excluded from the study. 40 patients satisfying inclusion and exclusion criteria were recruited irrespective of sex, duration and response of disease to previous therapies. 40 patients were allocated randomly to group 1 and 2. In group 1, 20 patients were treated with povidone iodine with dimethyl sulfoxide and in group 2: 20 patients were treated with 0.05% tretinoin. A detailed history was obtained, and a thorough general, systemic and cutaneous examination was done. Information regarding age, sex, number of lesions, duration of illness, site of involvement, family history, history of atopy and previous treatment were collected. Patients were randomly divided into two groups; 20 each for povidone iodine with dimethyl sulfoxide solution and 0.05% Tretinoin cream group. Parents or guardians were advised to apply petroleum jelly around the lesions followed by application of the above medication to the centre of the lesion using a cotton swab, to be applied once every day at bed time for 4 weeks. If accidental spillage occurred, they were advised to wash the skin with water immediately. Parents were asked to report local (erythema, itching, burning, pain, erosion, crusting) and systemic (fever, flu like illness, diarrhoea, mylagia) side effects immediately. Follow up assessment was done every week for 4 weeks. At each follow up visit, clinical assessment of lesion, photographic assessment of lesion and any side effects were noted. Efficacy assessment was done by weekly examination of patient every week for 4 weeks. In each visit complete remission of number of lesions were noted in both groups and photographic assessment was done. Photographic assessment was done based on resolution of number of lesion in each follow up visit for 4 weeks. Any side effects present were noted at each visit. Statistical Analysis Data was entered in Microsoft Excel and SPSS software was used for the analysis. Results were expressed in percentages and proportions. Chi- square test, unpaired T- test, was used for analysis Ethics Statement Study was conducted after taking ethical committee clearance.

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