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Sensors (Basel, Switzerland) Jun 2024This research focuses on developing an artificial vision system for a flexible delta robot manipulator and integrating it with machine-to-machine (M2M) communication to...
This research focuses on developing an artificial vision system for a flexible delta robot manipulator and integrating it with machine-to-machine (M2M) communication to optimize real-time device interaction. This integration aims to increase the speed of the robotic system and improve its overall performance. The proposed combination of an artificial vision system with M2M communication can detect and recognize targets with high accuracy in real time within the limited space considered for positioning, further localization, and carrying out manufacturing processes such as assembly or sorting of parts. In this study, RGB images are used as input data for the MASK-R-CNN algorithm, and the results are processed according to the features of the delta robot arm prototype. The data obtained from MASK-R-CNN are adapted for use in the delta robot control system, considering its unique characteristics and positioning requirements. M2M technology enables the robot arm to react quickly to changes, such as moving objects or changes in their position, which is crucial for sorting and packing tasks. The system was tested under near real-world conditions to evaluate its performance and reliability.
PubMed: 38931576
DOI: 10.3390/s24123792 -
Micromachines Jun 2024Microfabrication technology with quartz crystals is gaining importance as the miniaturization of quartz MEMS devices is essential to ensure the development of portable...
Microfabrication technology with quartz crystals is gaining importance as the miniaturization of quartz MEMS devices is essential to ensure the development of portable and wearable electronics. However, until now, there have been no reports of dimension compensation for quartz device fabrication. Therefore, this paper studied the wet etching process of Z-cut quartz crystal substrates for making deep trench patterns using Au/Cr metal hard masks and proposed the first quartz fabrication dimension compensation strategy. The size effect of various sizes of hard mask patterns on the undercut developed in wet etching was experimentally investigated. Quartz wafers masked with initial vias ranging from 3 μm to 80 μm in width were etched in a buffered oxide etch solution (BOE, HF:NHF = 3:2) at 80 °C for prolonged etching (>95 min). It was found that a larger hard mask width resulted in a smaller undercut, and a 30 μm difference in hard mask width would result in a 17.2% increase in undercut. In particular, the undercuts were mainly formed in the first 5 min of etching with a relatively high etching rate of 0.7 μm/min (max). Then, the etching rate decreased rapidly to 27%. Furthermore, based on the etching width compensation and etching position compensation, new solutions were proposed for quartz crystal device fabrication. And these two kinds of compensation solutions were used in the fabrication of an ultra-small quartz crystal tuning fork with a resonant frequency of 32.768 kHz. With these approaches, the actual etched size of critical parts of the device only deviated from the designed size by 0.7%. And the pattern position symmetry of the secondary lithography etching process was improved by 96.3% compared to the uncompensated one. It demonstrated significant potential for improving the fabrication accuracy of quartz crystal devices.
PubMed: 38930754
DOI: 10.3390/mi15060784 -
Micromachines Jun 2024High-aspect-ratio micro- and mesoscale metallic components (HAR-MMMCs) can play some unique roles in quite a few application fields, but their cost-efficient fabrication...
High-aspect-ratio micro- and mesoscale metallic components (HAR-MMMCs) can play some unique roles in quite a few application fields, but their cost-efficient fabrication is significantly difficult to accomplish. To address this issue, this study proposes a necked-entrance through-mask (NTM) periodically lifting electroforming technology with an impinging jet electrolyte supply. The effects of the size of the necked entrance of the through-mask and the jet speed of the electrolyte on electrodeposition behaviors, including the thickness distribution of the growing top surface, deposition defect formation, geometrical accuracy, and electrodeposition rate, are investigated numerically and experimentally. Ensuring an appropriate size of the necked entrance can effectively improve the uniformity of deposition thickness, while higher electrolyte flow velocities help enhance the density of the components under higher current densities, reducing the formation of deposition defects. It was shown that several precision HAR-MMMCs with an AR of 3.65 and a surface roughness (Ra) of down to 36 nm can be achieved simultaneously with a relatively high deposition rate of 3.6 μm/min and thickness variation as low as 1.4%. Due to the high current density and excellent mass transfer effects in the electroforming conditions, the successful electroforming of components with a Vickers microhardness of up to 520.5 HV was achieved. Mesoscale precision columns with circular and Y-shaped cross-sections were fabricated by using this modified through-mask movable electroforming process. The proposed NTM periodic lifting electroforming method is promisingly advantageous in fabricating precision HAR-MMMCs cost-efficiently.
PubMed: 38930723
DOI: 10.3390/mi15060753 -
Micromachines Jun 2024Thin transparent oxide layers are typically patterned for use in electronic products including semiconductors, displays, and solar cells for applications such as...
Thin transparent oxide layers are typically patterned for use in electronic products including semiconductors, displays, and solar cells for applications such as transparent electrodes, insulating films, and encapsulation films. Conventional patterning methods have traditionally been used in photolithography and lift-off processes. Photolithography employs the wet development process, which has disadvantages such as potential undercut effects, swelling, chemical contamination, and high process costs. On the other hand, laser ablation, which has the advantages of high accuracy, high speed, a noncontact nature, and selective processing, can be used to pattern thin films. However, absorption in transparent oxide films is usually low. In this study, experiments were conducted to determine the ablation characteristics of mask layers. The factors affecting ablation, including beam radii, fluences, overlap ratios, and coating thicknesses, were examined; and the parameters characteristic of residue-free ablation, namely the ablation threshold, minimum fluence, and minimum ablation linewidth, were also examined. The experimental results revealed that the beam radius was an important parameter in determining the resolutions of transparent films and substrates.
PubMed: 38930717
DOI: 10.3390/mi15060747 -
Medicina (Kaunas, Lithuania) May 2024Peri-implant soft tissue deficiency (PSTD) is a significant factor impacting aesthetics, particularly in the anterior zone, where labial bone resorption and thin...
Peri-implant soft tissue deficiency (PSTD) is a significant factor impacting aesthetics, particularly in the anterior zone, where labial bone resorption and thin peri-implant phenotypes are common. The occurrence of a gray color around the implant fixture due to PSTD can be aesthetically concerning in the esthetic zone. In cases involving natural teeth, autogenous soft tissue grafts such as subepithelial connective tissue grafts (SCTGs), free gingival grafts (FGGs), and coronally advanced flaps (CAFs) are commonly utilized. However, there are limited reports of using bone grafts in conjunction with these techniques for modifying the gingival phenotype around both teeth and implants. In the presented cases where PSTD resulted in visible gray coloration of the implant fixture in the esthetic zone, mechanical and chemical decontamination of the exposed implant surface was performed using a titanium brush and tetracycline (Tc) HCl. Subsequently, to enhance peri-implant mucosa thickness and mask the titanium color, simultaneous SCTG and bone grafting procedures were conducted. Within the limitations of these case reports, successful esthetic outcomes were achieved and maintained without recurrence for 3-6 years following the simultaneous subepithelial connective tissue graft and bone graft procedures. These findings suggest the potential efficacy of this combined approach in addressing PSTD and enhancing aesthetic results around dental implants, though further studies are needed to validate these outcomes.
Topics: Humans; Connective Tissue; Bone Transplantation; Female; Phenotype; Gingiva; Esthetics, Dental; Adult; Middle Aged; Male; Dental Implants
PubMed: 38929458
DOI: 10.3390/medicina60060841 -
International Journal of Environmental... Jun 2024Air pollution has emerged as a global public health concern. Specifically, in Medellín, Colombia, episodes of elevated air pollution have been documented. Medical...
Air pollution has emerged as a global public health concern. Specifically, in Medellín, Colombia, episodes of elevated air pollution have been documented. Medical students' knowledge of air pollution is paramount for implementing future interventions directed toward patients. The aim of this research was to delineate the knowledge, attitudes, and practices regarding air pollution among medical students at a private university in Medellín. A cross-sectional study involving 352 medical students was conducted. A questionnaire was administered, generating scores ranging from 0 to 100, where a higher score signified better knowledge, attitudes, and practices. Data were analyzed using frequencies, summary measures, non-parametric tests, and linear regression. : In total, 31% rated the education received at the university on the relationship between health and air quality as fair to poor, and 81% perceived the air quality in the city as poor. The knowledge score was 77.8 (IQR 71.1-85.6), with 90% acknowledging that exposure to air pollution increases the risk of various diseases. The attitudes score was 82.1 (IQR 71.8-87.2), and 25.9% believed that air pollution is a multifactorial problem, rendering their actions ineffective. In terms of practices, the score was 50 (IQR 42.9-57.1), indicating that students either did not employ protective measures against pollution or used inappropriate practices such as masks or air purifiers. Regression analysis revealed no association between knowledge and practices. The findings of this study underscore that medical students possess commendable knowledge regarding the health effects of air pollution. However, their adoption of inappropriate practices for self-protection is evident. The lack of correlation between knowledge and practices highlights the necessity of educational initiatives to be complemented by regulatory and cultural interventions.
Topics: Humans; Students, Medical; Health Knowledge, Attitudes, Practice; Female; Male; Air Pollution; Cross-Sectional Studies; Colombia; Surveys and Questionnaires; Young Adult; Adult
PubMed: 38929035
DOI: 10.3390/ijerph21060789 -
International Journal of Molecular... Jun 2024Bacterial contamination is a hazard in many industries, including food, pharmaceuticals, and healthcare. The availability of a rapid and simple method for detecting this...
Bacterial contamination is a hazard in many industries, including food, pharmaceuticals, and healthcare. The availability of a rapid and simple method for detecting this type of contamination in sterile areas enables immediate intervention to avoid or reduce detrimental effects. Among these methods, colorimetric indicators are becoming increasingly popular due to their affordability, ease of use, and quick visual interpretation of the signal. In this article, a bacterial contamination indicator system was designed by incorporating MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) into an electrospun PADAS matrix, which is a biodegradable poly(ester amide) synthesized from L-alanine, 1,12-dodecanediol, and sebacic acid. Uniaxial stress testing, thermogravimetric analysis and scanning electron microscopy were used to examine the mechanical properties, thermal stability, and morphology of the mats, respectively. The capacity for bacterial detection was not only analyzed with agar and broth assays but also by replicating important environmental conditions. Among the MTT concentrations tested in this study (0.2%, 2%, and 5%), it was found that only with a 2% MTT content the designed system produced a color response visible to the naked eye with optimal intensity, a sensitivity limit of 10 CFU/mL, and 86% cell viability, which showed the great potential for its use to detect bacterial contamination. In summary, by means of the process described in this work, it was possible to obtain a simple, low-cost and fast-response bacterial contamination indicator that can be used in mask filters, air filters, or protective clothing.
Topics: Tetrazolium Salts; Polyesters; Colorimetry; Thiazoles; Bacteria; Humans
PubMed: 38928377
DOI: 10.3390/ijms25126671 -
BMC Infectious Diseases Jun 2024Invasive meningococcal disease (IMD) cases declined upon the implementation of non-pharmaceutical interventions (NPI) (social distancing and mask wearing) to control the...
BACKGROUND
Invasive meningococcal disease (IMD) cases declined upon the implementation of non-pharmaceutical interventions (NPI) (social distancing and mask wearing) to control the COVID-19 pandemic but rebounded in 2022 in numbers with genotypical changes of the strains. We explored here associated modifications in the clinical presentations of IMD.
METHODS
We conducted a retrospective descriptive study using the Database of the French National Reference Centre for meningococci and Haemophilus influnezae for IMD cases between 2015 and 2022. We scored serogroups, sex, age groups, clinical presentations and clonal complexes of the corresponding patients and isolates.
FINDINGS
Non-meningeal forms of IMD increased significantly upon easing of NPI, such as bacteremic meningococcal pneumonia and bacteremic abdominal forms. They represented 6% and 8% of all IMD forms and were significantly linked to serogroups Y and W respectively, to older adults for bacteremic pneumonia and to young adults for bacteremic abdominal presentations. These forms were significantly associated with more early mortality and clonal complexes 23, 11 and 9316.
INTERPRETATION
The increase in atypical IMD forms may lead to higher burden of IMD due to delayed diagnosis and management. Updating prevention may be needed through by adapting the current vaccination strategies to epidemiological changes.
Topics: Humans; France; Retrospective Studies; Female; Male; Meningococcal Infections; Adult; Adolescent; Young Adult; Child; Child, Preschool; Middle Aged; Aged; Infant; Neisseria meningitidis; Serogroup; Bacteremia; Aged, 80 and over; COVID-19; Infant, Newborn
PubMed: 38926823
DOI: 10.1186/s12879-024-09547-y -
Scientific Reports Jun 2024COVID-19 surveillance in Ukraine ceased after the Russian invasion of the country in 2022, on a background of low vaccination rates of 34.5% for two doses at this time....
COVID-19 surveillance in Ukraine ceased after the Russian invasion of the country in 2022, on a background of low vaccination rates of 34.5% for two doses at this time. We conducted a modelling study to estimate the epidemic trajectory of SARS-COV-2 in Ukraine after the start of the war. We use a COVID-19 deterministic Susceptible-Exposed-Infected-Recovered (SEIR) model for Ukraine to estimate the impact of increased vaccination coverage and masking as public health interventions. We fit the model output to case notification data between 6 January and 25 February 2022, then we forecast the COVID-19 epidemic trajectory in different scenarios of mask use and vaccine coverage. In the best-case scenario, 69% of the Ukrainian population would have been infected in the first half of 2022. Increasing mask use from 50 to 80% reduces cases and deaths by 17% and 30% respectively, while increasing vaccination rates to 60% and 9.6% for two and three doses respectively results in a 3% reduction in cases and 28% in deaths. However, if vaccination is increased to a higher coverage of 80% with two doses and 12.8% with three, or mask effectiveness is reduced to 40%, increasing vaccination coverage is more effective. The loss of health services, displacement, and destruction of infrastructure will amplify the risk of COVID-19 in Ukraine and make vaccine programs less feasible. Masks do not need the health infrastructure or cold-chain logistics required for vaccines and are more feasible for rapid epidemic control during war. However, increasing vaccine coverage will save more lives. Vaccination of refugees who have fled to other countries can be more feasibly achieved.
Topics: Ukraine; Humans; COVID-19; COVID-19 Vaccines; Vaccination Coverage; SARS-CoV-2; Masks; Vaccination
PubMed: 38926448
DOI: 10.1038/s41598-024-57447-7 -
Toxics Jun 2024Since the early stages of the COVID-19 pandemic, there have been debates regarding the transmission modes of contagious viruses, including the influenza virus and severe...
Since the early stages of the COVID-19 pandemic, there have been debates regarding the transmission modes of contagious viruses, including the influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), along with its variants [...].
PubMed: 38922123
DOI: 10.3390/toxics12060443