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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 -
Journal of Cosmetic Dermatology Jun 2024Melasma is a prevalent pigmented disease, yet its pathogenesis remains unclear, posing challenges for effective treatment. Bibliometric analysis, a novel approach to...
BACKGROUND
Melasma is a prevalent pigmented disease, yet its pathogenesis remains unclear, posing challenges for effective treatment. Bibliometric analysis, a novel approach to literature research, offers the opportunity to evaluate research trends through qualitative and quantitative methods. This study utilizes bibliometric methods to analyze the existing literature on melasma treatment, examining influential publications, institutions, countries, and authors through statistical analysis.
METHODS
In order to retrieve manuscripts related to the topic of melasma treatment, we conducted a search using the search formula: (TS = (melasma or Chloasma or "mask of pregnancy")) AND TS = (treatment or therapy). We searched through the Web of Science Core Collection database, covering publications from 2000 to 2023. VOSviewer, CiteSpace and the Bibliometric online site (https://bibliometric.com/app) were used to conduct this bibliometric analysis. Our analysis focused on various factors including publications, authors co-authorship, institutions, countries, citation analysis, keywords co-occurrence, references co-citation and journal co-citation.
RESULTS
A total of 943 articles and 200 reviews were published between 2000 and 2023, accumulating a total of 8628 citations. The average number of citations per item was 18.85, and the average number of citations per year was 292.69. The most prolific author, Sungeun Chang, contributed a total of 9 articles. Cario University emerged as the top research institution. The United States led in terms of article publications with a count of 276. In the past 5 years, the research trends in this field have primarily focused on tranexamic acid and epidermal melasma, as indicated by the burst analysis of publications and keywords.
CONCLUSIONS
The United States continues to lead in terms of institutions and research output. The current emphasis is on the meticulous implementation of tranexamic acid and laser therapy. It is crucial to foster enhanced collaboration among countries, institutions, and authors to facilitate improved research.
PubMed: 38925583
DOI: 10.1111/jocd.16438 -
American Journal of Infection Control Jun 2024The use of personal protective equipment (PPE) in emergency departments (EDs) is an important defence during infectious disease emergencies. However, what counts as...
Risk assessment and the use of personal protective equipment in an emergency department: differing perspectives of emergency and infection control clinicians. A video-vignette survey.
BACKGROUND
The use of personal protective equipment (PPE) in emergency departments (EDs) is an important defence during infectious disease emergencies. However, what counts as appropriate PPE in EDs is contentious and inconsistently implemented in practice.
METHODS
An online scenario-based video-survey was distributed through purposive sampling, and completed by 270 ED and infection prevention and control (IPAC) clinicians in Australia. A descriptive content analysis was performed on the data, and differences between groups were tested using Fisher's exact test.
RESULTS
Participants agreed that most items were required for both scenarios. Eye protection, mask use and hand hygiene frequency were more contentious. Physicians were more likely than nurses, and ED clinicians more likely than IPAC clinicians, to regard items/actions as optional rather than essential. Many ED clinicians, particularly physicians, regarded sequences as too time-consuming to be practical in a busy emergency department.
DISCUSSION
Our findings likely reflect differences in professional roles, competing priorities and risks, and highlight important contextual characteristics of EDs, such as diagnostic uncertainty, equipment inaccessibility and resource constraints.
CONCLUSIONS
To be feasible, practicable and thereby effective, PPE guidance in the ED must be designed collaboratively with frontline ED staff, and reflect the complexities of their practice.
PubMed: 38925501
DOI: 10.1016/j.ajic.2024.06.012 -
The American Journal of Medicine Jun 2024In certain situations, masks are worn during sleep to prevent respiratory infections. However, the effects of mask wearing on cardiopulmonary function during sleep are...
Physiological effects and tolerance of wearing surgical and N95 masks during sleep in normal individuals and patients with mild-moderate obstructive sleep apnea: a randomized crossover trial.
BACKGROUND
In certain situations, masks are worn during sleep to prevent respiratory infections. However, the effects of mask wearing on cardiopulmonary function during sleep are unknown. This study aimed to determine whether wearing masks during sleep has an impact on cardiopulmonary function, including in patients with obstructive sleep apnea.
METHODS
This was a prospective, randomized crossover-controlled trial. The effects of wearing surgical masks or N95 respirators on cardiopulmonary function were measured in healthy subjects and patients with mild-moderate obstructive sleep apnea. Sleep breathing parameters were monitored during nocturnal sleep using a sleep monitor, and subjective feelings about mask wearing were assessed using a questionnaire.
RESULTS
Wearing masks during sleep at night did not significantly impact sleep breathing parameters. Furthermore, there were no significant differences in heart rate, blood oxygenation, and blood pressure before and after wearing masks. However, masks wearing, especially wearing N95 mask, had an adverse impact on sleep quality and were subjectively uncomfortable.
CONCLUSIONS
Wearing masks during sleep at night does not adversely affect cardiopulmonary function but it's uncomfortable, especially N95 mask. Thus, in circumstances where wearing N95 masks during nocturnal sleep proves intolerable, we recommend the use of surgical masks as a more comfortable alternative.
PubMed: 38925495
DOI: 10.1016/j.amjmed.2024.06.013