Search Results (14)

This paper presents a review of explosion mitigation techniques for road tunnels, with a focus on scenarios involving high-pressure hydrogen tank rupture under fire conditions. Both passive and active strategies are considered—including structural configurations (e.g., tunnel branching, vent openings, right-angle bends) and protective systems (e.g., drop-down perforated plates, high-performance fibre-reinforced cementitious composite (HPFRCC) panels)—to reduce blast impact on tunnel occupants and structures. The review highlights that while measures such as blast walls or energy-absorbing barriers can significantly attenuate blast pressures, an integrated approach addressing both blast load reduction and structural resilience is essential. This paper outlines how coupled computational fluid dynamics–finite element method (CFD–FEM) simulations can evaluate these mitigation methods, and we discuss design considerations (e.g., optimising barrier placement and tunnel geometry) for enhanced safety. The findings provide guidance for designing safer hydrogen vehicle tunnels, and they identify gaps for future research, including the need for experimental validation of combined CFD–FEM models in hydrogen fire–explosion scenarios. Full article

Palladium(II) complexes with tris(2-carboxyethyl)phosphine (PdTCEP) show promise for biomedical applications due to their distinct chemical characteristics. This study explored the toxicity of PdTCEP towards normal human cells and examined its interactions with model cell membranes. Two cell types were used to evaluate cytotoxicity: human microvascular endothelial cells (HMEC-1) and red blood cells (RBCs). In HMEC-1 cells, PdTCEP reduced survival to about 80% at 15 µM, with the most significant drop—down to 40%—occurring at 40 µM. The production of reactive oxygen species (ROS) increased in a manner dependent on both dose and time, especially after 72 h of incubation. Despite these effects, PdTCEP caused only minor hemolysis in RBCs, with hemolysis levels staying below 10% even at higher concentrations. Fluorescence anisotropy measurements showed that PdTCEP minimally affects the hydrophobic core of the lipid bilayer, with slight changes observed at concentrations above 40 µM. Generalized polarization (GP) analysis indicated a slight decrease in lipid polar head packing with increasing PdTCEP concentration. Complementary FTIR analysis supported these findings by providing detailed insights into PdTCEP-membrane interactions. This research underscores PdTCEP’s selective cytotoxicity and structural effects on membranes, suggesting its promise for more in-depth biological and pharmacological studies. Full article

Work is a recognized social determinant of health. This became most apparent during the COVID-19 pandemic. Workers, particularly those in certain industries and occupations, were at risk due to interaction with the public and close proximity to co-workers. The purpose of this study was to assess how states collected work and employment data on COVID-19 cases, characterizing the need for systematic collection of case-based specific work and employment data, including industry and occupation, of COVID-19 cases. A survey was distributed among state occupational health contacts and epidemiologists in all 50 states to assess current practices in state public health surveillance systems. Twenty-seven states collected some kind of work and employment information from COVID-19 cases. Most states (93%) collected industry and/or occupation information. More than half used text-only fields, a predefined reference or dropdown list, or both. Use of work and employment data included identifying high risk populations, prioritizing vaccination efforts, and assisting with reopening plans. Reported barriers to collecting industry and occupation data were lack of staffing, technology issues, and funding. Scientific understanding of work-related COVID-19 risk requires the systematic, case-based collection of specific work and employment data, including industry and occupation. While this alone does not necessarily indicate a clear workplace exposure, collection of these data elements can help to determine and further prevent workplace outbreaks, thereby ensuring the viability of the nation’s critical infrastructure. Full article

Supervised by three or four medical doctors and one nurse in rotating shifts, the medical clinic in Costa Rica’s Moín Container Terminal is open 24/7 for visits from port workers. In our study, we aimed to identify the sociodemographic and clinical characteristics of a consecutive series of patients who attended the medical clinic for outpatient services during an 8-month period. Our descriptive study involved collecting patient records from the medical clinic during the first 8 months of 2021 (i.e., 1 January–31 August 2021), during which 3050 visits from 1301 port workers were registered. Terminal tractor drivers, crane operators, and stevedores were the most frequent job categories among the patients. Doping (i.e., ICD-10 Z03.6) was observed in 64% of the visits. The top ICD-10 codes among all other patients not observed to have engaged in doping (n = 469) were diseases of the musculoskeletal system (7.2%) and abnormal clinical and laboratory symptoms (6.2%). Problems with the musculoskeletal system were primarily back pain (36.0%), muscle contracture (30.1%), and secondary headache (25.2%). Two-thirds of the visits were due to screening for alcohol and drugs or doping; however, inconsistency in the coding system complicates the analysis of data, and a dropdown menu in the registration is therefore needed to prevent errors. Relative risk calculations are impossible due to a lack of data about the at-risk population but should be pursued under different circumstances in future studies. In the support chain of goods, the medical clinic in the port plays a key role in saving time in shipping, which means that the injured or sick employees in most cases can continue working. For the shipping industry, quick un- and offloading is very important to stay competitive in the market for transport. Full article

Promoting consumers’ willingness to pay is crucial to creating a sustainable e-commerce environment, and the interaction design of the product configurator plays a key role in this. In the present study, the product configurator, which is indispensable in online customization, is adopted as the research object to analyze the influence of interaction design on the customization experience of consumers. The pricing method (total product pricing, incomplete total product pricing, and individual module pricing) and navigation design pattern (tabs and dropdown menu with arrow buttons) are adopted as independent variables, while system usability, flexible navigation capability, perceived control, perceived enjoyment, complexity and task performance are taken as dependent variables. One hundred and eighty college students participated in this study. The results of the 3 × 2 two-factor experiment reveal that: (1) Different navigation design patterns will lead to significant differences in system usability, flexible navigation capability, and perceived control of the product configurator, and tabs are better than dropdown menu with arrow buttons in these aspects. (2) Different pricing methods will significantly affect the perceived control of users. Under individual module pricing and incomplete total product pricing, perceived control is higher. (3) Different combinations of pricing methods and navigation design patterns will affect users’ evaluation of flexible navigation capability and complexity, and under the individual module pricing and incomplete total product pricing methods, users think that tabs have a higher flexible navigation capability and lower complexity. However, under the total product pricing method, users are convinced that dropdown menu with arrow buttons has a higher flexible navigation capability and lower complexity. The research results are of great significance to both interface interaction design and online customization. Furthermore, the interaction design method of price presentation and navigation design of the product configurator is analyzed to determine the most appropriate interaction design principles, so as to enhance the user experience of online customization and provide constructive ideas from the design perspective for online customization. Full article

Helicobacter species can colonize the gastrointestinal tract of both humans and animals, and are associated with gastrointestinal and extra-gastrointestinal diseases. Some studies indicate that animals, health professionals, and people in close contact with animals might be at higher risk for infection with gastric Helicobacter spp. Considering that veterinarians are professionals at risk for infection with zoonotic gastric Helicobacters and are also seen by many as health communicators concerning zoonoses, the aim of this study was to evaluate the Portuguese veterinarians’ perception and knowledge of Helicobacter spp. infection and its zoonotic risk/potential. Therefore, a structured questionnaire composed of 34 dichotomic, multiple-choice, rating scale, matrix, drop-down, and open-ended questions was developed and given to Portuguese veterinarians via an online platform from May 2021 to July 2021, and statistical analysis was used to obtain results. There was a total of 149 respondents, most of them (73.8%) being females. Evidently, Portuguese veterinarians have a limited perception regarding Helicobacter spp. infections. Of the respondents that “have heard of Helicobacter”, 17.6% do not know which animal species can be affected by it. Most of the companion animal veterinarians (76.2%) do not consider Helicobacter spp. infection a differential diagnosis when evaluating animals with gastritis. A significant percentage (37.2%) of the respondents that have “heard of H. suis” do not consider it a zoonotic bacterium. There is a need for education and sensitization of veterinarians regarding the potential zoonotic risk of Helicobacter spp. in order to elucidate these professionals to this One Health issue, as the number of reports of non-Helicobacter pylori Helicobacter in livestock, companion, and wild animals is increasing. Full article

Visual learning analytics (VLA) tools and technologies enable the meaningful exchange of information between educational data and teachers. This allows teachers to create meaningful groups of students based on possible collaboration and productive discussions. VLA tools also allow a better understanding of students’ educational demands. Finding similar samples in huge educational datasets, however, involves the use of effective similarity measures that represent the teacher’s purpose. In this study, we conducted a user study and improved our web-based similarity-based grouping VLA tool, (SBGTool) to help teachers categorize students into groups based on their similar learning outcomes and activities. SBGTool v2.0 differs from SBGTool due to design changes made in response to teacher suggestions, the addition of sorting options to the dashboard table, the addition of a dropdown component to group the students into classrooms, and improvement in some visualizations. To counteract color blindness, we have also considered a number of color palettes. By applying SBGTool v2.0, teachers may compare the outcomes of individual students inside a classroom, determine which subjects are the most and least difficult over the period of a week or an academic year, identify the numbers of correct and incorrect responses for the most difficult and easiest subjects, categorize students into various groups based on their learning outcomes, discover the week with the most interactions for examining students’ engagement, and find the relationship between students’ activity and study success. We used 10,000 random samples from the EdNet dataset, a large-scale hierarchical educational dataset consisting of student–system interactions from multiple platforms at the university level, collected over a two-year period, to illustrate the tool’s efficacy. Finally, we provide the outcomes of the user study that evaluated the tool’s effectiveness. The results revealed that even with limited training, the participants were able to complete the required analysis tasks. Additionally, the participants’ feedback showed that the SBGTool v2.0 gained a good level of support for the given tasks, and it had the potential to assist teachers in enhancing collaborative learning in their classrooms. Full article

In this study, two cruises were conducted across the mainstream of the Kuroshio off eastern Taiwan before and after the passage of Typhoon Saola in summer 2012. The continuous underway pCO₂ (i.e., partial pressure of CO₂) measurements revealed that surface seawater pCO₂ (SS pCO₂) displayed spatial variations in response to typhoon passage. The simulated results showed that the mixed-layer deepening after typhoon passage had a minor effect on SS pCO₂ variation because pCO₂ decrease driven by temperature dropdown and enhanced biological production fueled by nutrients input was largely compensated by pCO₂ increase caused by salinity increase and dissolved inorganic carbon input from the subsurface layer. By contrast, the advection pattern showed significant change before and after the typhoon, which could play a major role in controlling the variation of SS pCO₂. In the exit area of the cyclonic eddy, SS pCO₂ decreased, while in the area of its arrival, SS pCO₂ increased. Besides, the discharge of freshwater and the intrusion of the South China Sea subsurface could result in SS pCO₂ increase in the nearshore area. The present study highlights that more advection changes need to be considered to better understand the impact of the typhoon on SS pCO₂, especially in the strong current area, such as the Kuroshio. Full article

With an increase in renewable energy in the electricity grid, more storage capacity for grid stabilization and energy flexibilization is necessary. Dynamic grid stabilization is one possible application for flywheels. To increase the energy density of flywheels, they can be built as highly integrated outer rotor systems. The losses of the flywheel are reduced by magnetic levitation and operation under vacuum conditions. In the case of the failure or overload of the active magnetic bearings, the system needs touch-down bearings to prevent system destruction. Planetary touch-down bearings consisting of several small bearing units circumferentially distributed around the stator are especially suited for these systems. In the literature, these planetary touch-down bearings are rarely investigated, especially the number of bearing units. Therefore, this paper investigates the influence of the number of touch-down bearing elements in simulations and experiments for an 8-element and a 6-element touch-down bearing arrangement. For the investigation, drop-downs at four different speeds were performed. Simulation and experimental results showed that, for the 6-element touch-down bearing, in contrast to the 8-element touch-down bearing, maximal velocity did not increase with the drop-down speed. Therefore, the touch-down bearing arrangement with fewer elements is preferrable. Full article

In this paper a high capacitance ratio and low actuation voltage RF MEMS switch is designed and fabricated for Ka band RF front-ends application. The metal-insulator-metal (MIM) capacitors is employed on a signal line to improve the capacitance ratio, which will not degrade the switch reliability. To reduce the actuation voltage, a low spring constant bending folding beam and bilateral drop-down electrodes are designed in the MEMS switch. The paper analyzes the switch pull-in model and deduces the elastic coefficient calculation equation, which is consistent with the simulation results. The measured results indicated that, for the proposed MEMS switch with a gap of 2 μm, the insertion loss is better than −0.5 dB and the isolation is more than −20 dB from 25 to 35 GHz with an actuation voltage of 15.8 V. From the fitted results, the up-state capacitance is 6.5 fF, down-state capacitance is 4.3 pF, and capacitance ratios is 162. Compared with traditional MEMS capacitive switches with dielectric material Si₃N₄, the proposed MEMS switch exhibits high on/off capacitance ratios of 162 and low actuation voltage. Full article

Resilient crop-livestock production systems become crucial to face environmental challenges such as climate mitigation. Progress in the SDG 2.4.1 indicator (proportion of agricultural area under productive and sustainable agriculture) requires robustness, adaptability, and transformation. Most literature considers gender equality and crops livestock investment as drivers to environmental sustainability. In Cosculluela-Martínez (2020), the productivity and the employing capacity of the investment in agricultural capital stock has been analyzed. However, nobody has examined the long and short-run effects on climate change and the gender gap of investing in the crop-livestock production system’s assets. In this paper, the investment’s empowerment is assessed by estimating the impact of an investment in capital stock on climate, gender gap drop-down, and production through a Vector Error Correction Model. To reduce the gender gap in the agricultural sector in 8 of the 11 countries. Policy and implications of different weights in the distribution of the investment of European Funds are discussed. Full article

Background and Objectives: There is limited research on the question of whether web-based preoperative education can improve surgical patient outcomes. The purpose of this pilot study was to determine the usability, utility, and feasibility of a website created to increase engagement and improve the quality of the preoperative education that patients having hip and knee arthroplasty surgery receive. Materials and Methods: A website was created, and its appearance was designed with evidence-based “menu-driven” drop-downs to make the screen options age-appropriate to the patient population; the content was supported with video and PDFs of educational material, the same or similar to the usual education provided to patients. The patient-specific outcomes included qualitative data regarding patient knowledge, satisfaction, utilities, and usability. These objectives were assessed based on the perceived health website usability questionnaire online survey. Eighty patients who met inclusion criteria were recruited, ranging in age from 40 to 65 years old. Among them, 52.5% were female, 71.25% were scheduled for knee arthroplasty, and 28.75% hip arthroplasty. The patients were randomly assigned to the paper only or website education cohorts in a 50:50 ratio. However, only 19 from each cohort participated in the survey questionnaire. Results and Conclusions: We hypothesized that findings would show that patients receiving web-based education would feel more knowledgeable about their procedure, have less anxiety, and greater satisfaction with the addition of the website content; and that nurses would report that a website could conserve nursing time and resources. The study revealed no statistically significant differences between the cohorts, with an Alpha level set at 0.05. However, survey results showed that patients using the website rated self-perceived increase in knowledge, and their satisfaction in the time to find and review the information was higher than that of the paper-only cohort. The nursing survey revealed that website education improved workflow, efficiency, and patient education. Full article

Currently, multi-antigenic vaccine use is the method of choice for the strategic control of ticks. Therefore, determining the efficacy of combined antigens is a promising avenue of research in the development of anti-tick vaccines. The antigen responsible for blood intake and reproduction has proven suitable as a vaccine antigen. It has been shown to silence Haemaphysalis longicornis salivary cystatin (HlSC-1) and subolesin by RNA interference. Adult unfed female ticks were injected with double-stranded RNA of (A) subolesin, (B) cystatin, (C) subolesin plus cystatin, and (D) injection buffer, then fed alongside normal unfed males up to spontaneous drop-down. The percentage of knockdowns was determined by real-time polymerase chain reaction. Sixty-three percent and 53% knockdown rates were observed in subolesin and cystatin double-stranded RNA-injected ticks respectively, while 32 and 26% knockdown rates of subolesin and cystatin transcript were observed in subolesin plus cystatin double-stranded RNA-injected ticks. Subolesin and/or cystatin knockdown causes a significant (p < 0.05) reduction in tick engorgement, egg mass weight, and egg conversion ratio. Most importantly, combined silencing did not act synergistically, but caused a similarly significant (p < 0.05) reduction in tick engorgement, egg mass weight, and egg conversion ratio. Therefore, the elucidation of multiple antigens may be helpful in the future of vaccines. Full article

Hollow halloysite nanotubes have been used as nanocontainers for loading and for the triggered release of calcium hydroxide for paper preservation. A strategy for placing end-stoppers into the tubular nanocontainer is proposed and the sustained release from the cavity is reported. The incorporation of Ca(OH)₂ into the nanotube lumen, as demonstrated using transmission electron microscopy (TEM) imaging and Energy Dispersive X-ray (EDX) mapping, retards the carbonatation, delaying the reaction with CO₂ gas. This effect can be further controlled by placing the end-stoppers. The obtained material is tested for paper deacidification. We prove that adding halloysite filled with Ca(OH)₂ to paper can reduce the impact of acid exposure on both the mechanical performance and pH alteration. The end-stoppers have a double effect: they preserve the calcium hydroxide from carbonation, and they prevent from the formation of highly basic pH and trigger the response to acid exposure minimizing the pH drop-down. These features are promising for a composite nanoadditive in the smart protection of cellulose-based materials. Full article